diff options
Diffstat (limited to 'Documentation/arm')
70 files changed, 4058 insertions, 660 deletions
diff --git a/Documentation/arm/00-INDEX b/Documentation/arm/00-INDEX index 2c6a3b38967..3b08bc2b04c 100644 --- a/Documentation/arm/00-INDEX +++ b/Documentation/arm/00-INDEX @@ -4,19 +4,49 @@ Booting - requirements for booting Interrupts - ARM Interrupt subsystem documentation +IXP4xx + - Intel IXP4xx Network processor. +msm + - MSM specific documentation Netwinder - Netwinder specific documentation +Porting + - Symbol definitions for porting Linux to a new ARM machine. +Setup + - Kernel initialization parameters on ARM Linux README - General ARM documentation -SA1100 +SA1100/ - SA1100 documentation -XScale - - XScale documentation -empeg - - Empeg documentation +Samsung-S3C24XX + - S3C24XX ARM Linux Overview +Sharp-LH + - Linux on Sharp LH79524 and LH7A40X System On a Chip (SOC) +SPEAr + - ST SPEAr platform Linux Overview +VFP/ + - Release notes for Linux Kernel Vector Floating Point support code +cluster-pm-race-avoidance.txt + - Algorithm for CPU and Cluster setup/teardown +empeg/ + - Ltd's Empeg MP3 Car Audio Player +firmware.txt + - Secure firmware registration and calling. +kernel_mode_neon.txt + - How to use NEON instructions in kernel mode +kernel_user_helpers.txt + - Helper functions in kernel space made available for userspace. mem_alignment - alignment abort handler documentation memory.txt - description of the virtual memory layout -nwfpe +nwfpe/ - NWFPE floating point emulator documentation +swp_emulation + - SWP/SWPB emulation handler/logging description +tcm.txt + - ARM Tightly Coupled Memory +uefi.txt + - [U]EFI configuration and runtime services documentation +vlocks.txt + - Voting locks, low-level mechanism relying on memory system atomic writes. diff --git a/Documentation/arm/Booting b/Documentation/arm/Booting index 76850295af8..371814a3671 100644 --- a/Documentation/arm/Booting +++ b/Documentation/arm/Booting @@ -18,7 +18,8 @@ following: 2. Initialise one serial port. 3. Detect the machine type. 4. Setup the kernel tagged list. -5. Call the kernel image. +5. Load initramfs. +6. Call the kernel image. 1. Setup and initialise RAM @@ -65,13 +66,19 @@ looks at the connected hardware is beyond the scope of this document. The boot loader must ultimately be able to provide a MACH_TYPE_xxx value to the kernel. (see linux/arch/arm/tools/mach-types). - -4. Setup the kernel tagged list -------------------------------- +4. Setup boot data +------------------ Existing boot loaders: OPTIONAL, HIGHLY RECOMMENDED New boot loaders: MANDATORY +The boot loader must provide either a tagged list or a dtb image for +passing configuration data to the kernel. The physical address of the +boot data is passed to the kernel in register r2. + +4a. Setup the kernel tagged list +-------------------------------- + The boot loader must create and initialise the kernel tagged list. A valid tagged list starts with ATAG_CORE and ends with ATAG_NONE. The ATAG_CORE tag may or may not be empty. An empty ATAG_CORE tag @@ -101,7 +108,40 @@ The tagged list must be placed in a region of memory where neither the kernel decompressor nor initrd 'bootp' program will overwrite it. The recommended placement is in the first 16KiB of RAM. -5. Calling the kernel image +4b. Setup the device tree +------------------------- + +The boot loader must load a device tree image (dtb) into system ram +at a 64bit aligned address and initialize it with the boot data. The +dtb format is documented in Documentation/devicetree/booting-without-of.txt. +The kernel will look for the dtb magic value of 0xd00dfeed at the dtb +physical address to determine if a dtb has been passed instead of a +tagged list. + +The boot loader must pass at a minimum the size and location of the +system memory, and the root filesystem location. The dtb must be +placed in a region of memory where the kernel decompressor will not +overwrite it, whilst remaining within the region which will be covered +by the kernel's low-memory mapping. + +A safe location is just above the 128MiB boundary from start of RAM. + +5. Load initramfs. +------------------ + +Existing boot loaders: OPTIONAL +New boot loaders: OPTIONAL + +If an initramfs is in use then, as with the dtb, it must be placed in +a region of memory where the kernel decompressor will not overwrite it +while also with the region which will be covered by the kernel's +low-memory mapping. + +A safe location is just above the device tree blob which itself will +be loaded just above the 128MiB boundary from the start of RAM as +recommended above. + +6. Calling the kernel image --------------------------- Existing boot loaders: MANDATORY @@ -112,11 +152,17 @@ is stored in flash, and is linked correctly to be run from flash, then it is legal for the boot loader to call the zImage in flash directly. -The zImage may also be placed in system RAM (at any location) and -called there. Note that the kernel uses 16K of RAM below the image -to store page tables. The recommended placement is 32KiB into RAM. +The zImage may also be placed in system RAM and called there. The +kernel should be placed in the first 128MiB of RAM. It is recommended +that it is loaded above 32MiB in order to avoid the need to relocate +prior to decompression, which will make the boot process slightly +faster. -In either case, the following conditions must be met: +When booting a raw (non-zImage) kernel the constraints are tighter. +In this case the kernel must be loaded at an offset into system equal +to TEXT_OFFSET - PAGE_OFFSET. + +In any case, the following conditions must be met: - Quiesce all DMA capable devices so that memory does not get corrupted by bogus network packets or disk data. This will save @@ -125,17 +171,43 @@ In either case, the following conditions must be met: - CPU register settings r0 = 0, r1 = machine type number discovered in (3) above. - r2 = physical address of tagged list in system RAM. + r2 = physical address of tagged list in system RAM, or + physical address of device tree block (dtb) in system RAM - CPU mode All forms of interrupts must be disabled (IRQs and FIQs) - The CPU must be in SVC mode. (A special exception exists for Angel) + + For CPUs which do not include the ARM virtualization extensions, the + CPU must be in SVC mode. (A special exception exists for Angel) + + CPUs which include support for the virtualization extensions can be + entered in HYP mode in order to enable the kernel to make full use of + these extensions. This is the recommended boot method for such CPUs, + unless the virtualisations are already in use by a pre-installed + hypervisor. + + If the kernel is not entered in HYP mode for any reason, it must be + entered in SVC mode. - Caches, MMUs The MMU must be off. Instruction cache may be on or off. Data cache must be off. + If the kernel is entered in HYP mode, the above requirements apply to + the HYP mode configuration in addition to the ordinary PL1 (privileged + kernel modes) configuration. In addition, all traps into the + hypervisor must be disabled, and PL1 access must be granted for all + peripherals and CPU resources for which this is architecturally + possible. Except for entering in HYP mode, the system configuration + should be such that a kernel which does not include support for the + virtualization extensions can boot correctly without extra help. + - The boot loader is expected to call the kernel image by jumping directly to the first instruction of the kernel image. + On CPUs supporting the ARM instruction set, the entry must be + made in ARM state, even for a Thumb-2 kernel. + + On CPUs supporting only the Thumb instruction set such as + Cortex-M class CPUs, the entry must be made in Thumb state. diff --git a/Documentation/arm/IXP2000 b/Documentation/arm/IXP2000 deleted file mode 100644 index e0148b6b2c4..00000000000 --- a/Documentation/arm/IXP2000 +++ /dev/null @@ -1,69 +0,0 @@ - -------------------------------------------------------------------------- -Release Notes for Linux on Intel's IXP2000 Network Processor - -Maintained by Deepak Saxena <dsaxena@plexity.net> -------------------------------------------------------------------------- - -1. Overview - -Intel's IXP2000 family of NPUs (IXP2400, IXP2800, IXP2850) is designed -for high-performance network applications such high-availability -telecom systems. In addition to an XScale core, it contains up to 8 -"MicroEngines" that run special code, several high-end networking -interfaces (UTOPIA, SPI, etc), a PCI host bridge, one serial port, -flash interface, and some other odds and ends. For more information, see: - -http://developer.intel.com/design/network/products/npfamily/ixp2xxx.htm - -2. Linux Support - -Linux currently supports the following features on the IXP2000 NPUs: - -- On-chip serial -- PCI -- Flash (MTD/JFFS2) -- I2C through GPIO -- Timers (watchdog, OS) - -That is about all we can support under Linux ATM b/c the core networking -components of the chip are accessed via Intel's closed source SDK. -Please contact Intel directly on issues with using those. There is -also a mailing list run by some folks at Princeton University that might -be of help: https://lists.cs.princeton.edu/mailman/listinfo/ixp2xxx - -WHATEVER YOU DO, DO NOT POST EMAIL TO THE LINUX-ARM OR LINUX-ARM-KERNEL -MAILING LISTS REGARDING THE INTEL SDK. - -3. Supported Platforms - -- Intel IXDP2400 Reference Platform -- Intel IXDP2800 Reference Platform -- Intel IXDP2401 Reference Platform -- Intel IXDP2801 Reference Platform -- RadiSys ENP-2611 - -4. Usage Notes - -- The IXP2000 platforms usually have rather complex PCI bus topologies - with large memory space requirements. In addition, b/c of the way the - Intel SDK is designed, devices are enumerated in a very specific - way. B/c of this this, we use "pci=firmware" option in the kernel - command line so that we do not re-enumerate the bus. - -- IXDP2x01 systems have variable clock tick rates that we cannot determine - via HW registers. The "ixdp2x01_clk=XXX" cmd line options allow you - to pass the clock rate to the board port. - -5. Thanks - -The IXP2000 work has been funded by Intel Corp. and MontaVista Software, Inc. - -The following people have contributed patches/comments/etc: - -Naeem F. Afzal -Lennert Buytenhek -Jeffrey Daly - -------------------------------------------------------------------------- -Last Update: 8/09/2004 diff --git a/Documentation/arm/IXP4xx b/Documentation/arm/IXP4xx index 43edb4ecf27..e48b74de6ac 100644 --- a/Documentation/arm/IXP4xx +++ b/Documentation/arm/IXP4xx @@ -32,11 +32,11 @@ Linux currently supports the following features on the IXP4xx chips: - Flash access (MTD/JFFS) - I2C through GPIO on IXP42x - GPIO for input/output/interrupts - See include/asm-arm/arch-ixp4xx/platform.h for access functions. + See arch/arm/mach-ixp4xx/include/mach/platform.h for access functions. - Timers (watchdog, OS) The following components of the chips are not supported by Linux and -require the use of Intel's propietary CSR softare: +require the use of Intel's proprietary CSR software: - USB device interface - Network interfaces (HSS, Utopia, NPEs, etc) @@ -45,15 +45,15 @@ require the use of Intel's propietary CSR softare: If you need to use any of the above, you need to download Intel's software from: - http://developer.intel.com/design/network/products/npfamily/ixp425swr1.htm + http://developer.intel.com/design/network/products/npfamily/ixp425.htm -DO NOT POST QUESTIONS TO THE LINUX MAILING LISTS REGARDING THE PROPIETARY +DO NOT POST QUESTIONS TO THE LINUX MAILING LISTS REGARDING THE PROPRIETARY SOFTWARE. There are several websites that provide directions/pointers on using Intel's software: -http://ixp4xx-osdg.sourceforge.net/ + http://sourceforge.net/projects/ixp4xx-osdg/ Open Source Developer's Guide for using uClinux and the Intel libraries http://gatewaymaker.sourceforge.net/ @@ -112,21 +112,21 @@ http://www.adiengineering.com/productsCoyote.html Finally, there is an IDE port hanging off the expansion bus. Gateworks Avila Network Platform -http://www.gateworks.com/avila_sbc.htm +http://www.gateworks.com/support/overview.php The Avila platform is basically and IXDP425 with the 4 PCI slots replaced with mini-PCI slots and a CF IDE interface hanging off the expansion bus. Intel IXDP425 Development Platform -http://developer.intel.com/design/network/products/npfamily/ixdp425.htm +http://www.intel.com/design/network/products/npfamily/ixdpg425.htm This is Intel's standard reference platform for the IXDP425 and is also known as the Richfield board. It contains 4 PCI slots, 16MB of flash, two 10/100 ports and one ADSL port. Intel IXDP465 Development Platform -http://developer.intel.com/design/network/products/npfamily/ixdp465.htm +http://www.intel.com/design/network/products/npfamily/ixdp465.htm This is basically an IXDP425 with an IXP465 and 32M of flash instead of just 16. @@ -141,15 +141,13 @@ Intel IXDPG425 Development Platform a pivot_root to NFS. Motorola PrPMC1100 Processor Mezanine Card -http://www.fountainsys.com/datasheet/PrPMC1100.pdf +http://www.fountainsys.com The PrPMC1100 is based on the IXCP1100 and is meant to plug into and IXP2400/2800 system to act as the system controller. It simply contains a CPU and 16MB of flash on the board and needs to be plugged into a carrier board to function. Currently Linux only supports the Motorola PrPMC carrier board for this platform. - See https://mcg.motorola.com/us/ds/pdf/ds0144.pdf for info - on the carrier board. 5. TODO LIST diff --git a/Documentation/arm/Interrupts b/Documentation/arm/Interrupts index 72c93de8cd4..f09ab1b90ef 100644 --- a/Documentation/arm/Interrupts +++ b/Documentation/arm/Interrupts @@ -138,18 +138,12 @@ So, what's changed? Set active the IRQ edge(s)/level. This replaces the SA1111 INTPOL manipulation, and the set_GPIO_IRQ_edge() - function. Type should be one of the following: - - #define IRQT_NOEDGE (0) - #define IRQT_RISING (__IRQT_RISEDGE) - #define IRQT_FALLING (__IRQT_FALEDGE) - #define IRQT_BOTHEDGE (__IRQT_RISEDGE|__IRQT_FALEDGE) - #define IRQT_LOW (__IRQT_LOWLVL) - #define IRQT_HIGH (__IRQT_HIGHLVL) + function. Type should be one of IRQ_TYPE_xxx defined in + <linux/irq.h> 3. set_GPIO_IRQ_edge() is obsolete, and should be replaced by set_irq_type. -4. Direct access to SA1111 INTPOL is depreciated. Use set_irq_type instead. +4. Direct access to SA1111 INTPOL is deprecated. Use set_irq_type instead. 5. A handler is expected to perform any necessary acknowledgement of the parent IRQ via the correct chip specific function. For instance, if @@ -164,7 +158,7 @@ So, what's changed? be re-checked for pending events. (see the Neponset IRQ handler for details). -7. fixup_irq() is gone, as is include/asm-arm/arch-*/irq.h +7. fixup_irq() is gone, as is arch/arm/mach-*/include/mach/irq.h Please note that this will not solve all problems - some of them are hardware based. Mixing level-based and edge-based IRQs on the same diff --git a/Documentation/arm/Marvell/README b/Documentation/arm/Marvell/README new file mode 100644 index 00000000000..2cce5401e32 --- /dev/null +++ b/Documentation/arm/Marvell/README @@ -0,0 +1,272 @@ +ARM Marvell SoCs +================ + +This document lists all the ARM Marvell SoCs that are currently +supported in mainline by the Linux kernel. As the Marvell families of +SoCs are large and complex, it is hard to understand where the support +for a particular SoC is available in the Linux kernel. This document +tries to help in understanding where those SoCs are supported, and to +match them with their corresponding public datasheet, when available. + +Orion family +------------ + + Flavors: + 88F5082 + 88F5181 + 88F5181L + 88F5182 + Datasheet : http://www.embeddedarm.com/documentation/third-party/MV88F5182-datasheet.pdf + Programmer's User Guide : http://www.embeddedarm.com/documentation/third-party/MV88F5182-opensource-manual.pdf + User Manual : http://www.embeddedarm.com/documentation/third-party/MV88F5182-usermanual.pdf + 88F5281 + Datasheet : http://www.ocmodshop.com/images/reviews/networking/qnap_ts409u/marvel_88f5281_data_sheet.pdf + 88F6183 + Core: Feroceon ARMv5 compatible + Linux kernel mach directory: arch/arm/mach-orion5x + Linux kernel plat directory: arch/arm/plat-orion + +Kirkwood family +--------------- + + Flavors: + 88F6282 a.k.a Armada 300 + Product Brief : http://www.marvell.com/embedded-processors/armada-300/assets/armada_310.pdf + 88F6283 a.k.a Armada 310 + Product Brief : http://www.marvell.com/embedded-processors/armada-300/assets/armada_310.pdf + 88F6190 + Product Brief : http://www.marvell.com/embedded-processors/kirkwood/assets/88F6190-003_WEB.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F619x_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf + 88F6192 + Product Brief : http://www.marvell.com/embedded-processors/kirkwood/assets/88F6192-003_ver1.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F619x_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf + 88F6182 + 88F6180 + Product Brief : http://www.marvell.com/embedded-processors/kirkwood/assets/88F6180-003_ver1.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F6180_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf + 88F6281 + Product Brief : http://www.marvell.com/embedded-processors/kirkwood/assets/88F6281-004_ver1.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F6281_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf + Homepage: http://www.marvell.com/embedded-processors/kirkwood/ + Core: Feroceon ARMv5 compatible + Linux kernel mach directory: arch/arm/mach-kirkwood + Linux kernel plat directory: arch/arm/plat-orion + +Discovery family +---------------- + + Flavors: + MV78100 + Product Brief : http://www.marvell.com/embedded-processors/discovery-innovation/assets/MV78100-003_WEB.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/discovery-innovation/assets/HW_MV78100_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/discovery-innovation/assets/FS_MV76100_78100_78200_OpenSource.pdf + MV78200 + Product Brief : http://www.marvell.com/embedded-processors/discovery-innovation/assets/MV78200-002_WEB.pdf + Hardware Spec : http://www.marvell.com/embedded-processors/discovery-innovation/assets/HW_MV78200_OpenSource.pdf + Functional Spec: http://www.marvell.com/embedded-processors/discovery-innovation/assets/FS_MV76100_78100_78200_OpenSource.pdf + MV76100 + Not supported by the Linux kernel. + + Core: Feroceon ARMv5 compatible + + Linux kernel mach directory: arch/arm/mach-mv78xx0 + Linux kernel plat directory: arch/arm/plat-orion + +EBU Armada family +----------------- + + Armada 370 Flavors: + 88F6710 + 88F6707 + 88F6W11 + Product Brief: http://www.marvell.com/embedded-processors/armada-300/assets/Marvell_ARMADA_370_SoC.pdf + + Armada 375 Flavors: + 88F6720 + Product Brief: http://www.marvell.com/embedded-processors/armada-300/assets/ARMADA_375_SoC-01_product_brief.pdf + + Armada 380/385 Flavors: + 88F6810 + 88F6820 + 88F6828 + + Armada XP Flavors: + MV78230 + MV78260 + MV78460 + NOTE: not to be confused with the non-SMP 78xx0 SoCs + Product Brief: http://www.marvell.com/embedded-processors/armada-xp/assets/Marvell-ArmadaXP-SoC-product%20brief.pdf + + No public datasheet available. + + Core: Sheeva ARMv7 compatible + + Linux kernel mach directory: arch/arm/mach-mvebu + Linux kernel plat directory: none + +Avanta family +------------- + + Flavors: + 88F6510 + 88F6530P + 88F6550 + 88F6560 + Homepage : http://www.marvell.com/broadband/ + Product Brief: http://www.marvell.com/broadband/assets/Marvell_Avanta_88F6510_305_060-001_product_brief.pdf + No public datasheet available. + + Core: ARMv5 compatible + + Linux kernel mach directory: no code in mainline yet, planned for the future + Linux kernel plat directory: no code in mainline yet, planned for the future + +Dove family (application processor) +----------------------------------- + + Flavors: + 88AP510 a.k.a Armada 510 + Product Brief : http://www.marvell.com/application-processors/armada-500/assets/Marvell_Armada510_SoC.pdf + Hardware Spec : http://www.marvell.com/application-processors/armada-500/assets/Armada-510-Hardware-Spec.pdf + Functional Spec : http://www.marvell.com/application-processors/armada-500/assets/Armada-510-Functional-Spec.pdf + Homepage: http://www.marvell.com/application-processors/armada-500/ + Core: ARMv7 compatible + Directory: arch/arm/mach-dove + +PXA 2xx/3xx/93x/95x family +-------------------------- + + Flavors: + PXA21x, PXA25x, PXA26x + Application processor only + Core: ARMv5 XScale core + PXA270, PXA271, PXA272 + Product Brief : http://www.marvell.com/application-processors/pxa-family/assets/pxa_27x_pb.pdf + Design guide : http://www.marvell.com/application-processors/pxa-family/assets/pxa_27x_design_guide.pdf + Developers manual : http://www.marvell.com/application-processors/pxa-family/assets/pxa_27x_dev_man.pdf + Specification : http://www.marvell.com/application-processors/pxa-family/assets/pxa_27x_emts.pdf + Specification update : http://www.marvell.com/application-processors/pxa-family/assets/pxa_27x_spec_update.pdf + Application processor only + Core: ARMv5 XScale core + PXA300, PXA310, PXA320 + PXA 300 Product Brief : http://www.marvell.com/application-processors/pxa-family/assets/PXA300_PB_R4.pdf + PXA 310 Product Brief : http://www.marvell.com/application-processors/pxa-family/assets/PXA310_PB_R4.pdf + PXA 320 Product Brief : http://www.marvell.com/application-processors/pxa-family/assets/PXA320_PB_R4.pdf + Design guide : http://www.marvell.com/application-processors/pxa-family/assets/PXA3xx_Design_Guide.pdf + Developers manual : http://www.marvell.com/application-processors/pxa-family/assets/PXA3xx_Developers_Manual.zip + Specifications : http://www.marvell.com/application-processors/pxa-family/assets/PXA3xx_EMTS.pdf + Specification Update : http://www.marvell.com/application-processors/pxa-family/assets/PXA3xx_Spec_Update.zip + Reference Manual : http://www.marvell.com/application-processors/pxa-family/assets/PXA3xx_TavorP_BootROM_Ref_Manual.pdf + Application processor only + Core: ARMv5 XScale core + PXA930, PXA935 + Application processor with Communication processor + Core: ARMv5 XScale core + PXA955 + Application processor with Communication processor + Core: ARMv7 compatible Sheeva PJ4 core + + Comments: + + * This line of SoCs originates from the XScale family developed by + Intel and acquired by Marvell in ~2006. The PXA21x, PXA25x, + PXA26x, PXA27x, PXA3xx and PXA93x were developed by Intel, while + the later PXA95x were developed by Marvell. + + * Due to their XScale origin, these SoCs have virtually nothing in + common with the other (Kirkwood, Dove, etc.) families of Marvell + SoCs, except with the MMP/MMP2 family of SoCs. + + Linux kernel mach directory: arch/arm/mach-pxa + Linux kernel plat directory: arch/arm/plat-pxa + +MMP/MMP2 family (communication processor) +----------------------------------------- + + Flavors: + PXA168, a.k.a Armada 168 + Homepage : http://www.marvell.com/application-processors/armada-100/armada-168.jsp + Product brief : http://www.marvell.com/application-processors/armada-100/assets/pxa_168_pb.pdf + Hardware manual : http://www.marvell.com/application-processors/armada-100/assets/armada_16x_datasheet.pdf + Software manual : http://www.marvell.com/application-processors/armada-100/assets/armada_16x_software_manual.pdf + Specification update : http://www.marvell.com/application-processors/armada-100/assets/ARMADA16x_Spec_update.pdf + Boot ROM manual : http://www.marvell.com/application-processors/armada-100/assets/armada_16x_ref_manual.pdf + App node package : http://www.marvell.com/application-processors/armada-100/assets/armada_16x_app_note_package.pdf + Application processor only + Core: ARMv5 compatible Marvell PJ1 (Mohawk) + PXA910 + Homepage : http://www.marvell.com/communication-processors/pxa910/ + Product Brief : http://www.marvell.com/communication-processors/pxa910/assets/Marvell_PXA910_Platform-001_PB_final.pdf + Application processor with Communication processor + Core: ARMv5 compatible Marvell PJ1 (Mohawk) + MMP2, a.k.a Armada 610 + Product Brief : http://www.marvell.com/application-processors/armada-600/assets/armada610_pb.pdf + Application processor only + Core: ARMv7 compatible Sheeva PJ4 core + + Comments: + + * This line of SoCs originates from the XScale family developed by + Intel and acquired by Marvell in ~2006. All the processors of + this MMP/MMP2 family were developed by Marvell. + + * Due to their XScale origin, these SoCs have virtually nothing in + common with the other (Kirkwood, Dove, etc.) families of Marvell + SoCs, except with the PXA family of SoCs listed above. + + Linux kernel mach directory: arch/arm/mach-mmp + Linux kernel plat directory: arch/arm/plat-pxa + +Berlin family (Digital Entertainment) +------------------------------------- + + Flavors: + 88DE3005, Armada 1500-mini + Design name: BG2CD + Core: ARM Cortex-A9, PL310 L2CC + Homepage: http://www.marvell.com/digital-entertainment/armada-1500-mini/ + 88DE3100, Armada 1500 + Design name: BG2 + Core: Marvell PJ4B (ARMv7), Tauros3 L2CC + Homepage: http://www.marvell.com/digital-entertainment/armada-1500/ + Product Brief: http://www.marvell.com/digital-entertainment/armada-1500/assets/Marvell-ARMADA-1500-Product-Brief.pdf + 88DE3114, Armada 1500 Pro + Design name: BG2-Q + Core: Quad Core ARM Cortex-A9, PL310 L2CC + Homepage: http://www.marvell.com/digital-entertainment/armada-1500-pro/ + Product Brief: http://www.marvell.com/digital-entertainment/armada-1500-pro/assets/Marvell_ARMADA_1500_PRO-01_product_brief.pdf + 88DE???? + Design name: BG3 + Core: ARM Cortex-A15, CA15 integrated L2CC + + Homepage: http://www.marvell.com/digital-entertainment/ + Directory: arch/arm/mach-berlin + + Comments: + * This line of SoCs is based on Marvell Sheeva or ARM Cortex CPUs + with Synopsys DesignWare (IRQ, GPIO, Timers, ...) and PXA IP (SDHCI, USB, ETH, ...). + +Long-term plans +--------------- + + * Unify the mach-dove/, mach-mv78xx0/, mach-orion5x/ and + mach-kirkwood/ into the mach-mvebu/ to support all SoCs from the + Marvell EBU (Engineering Business Unit) in a single mach-<foo> + directory. The plat-orion/ would therefore disappear. + + * Unify the mach-mmp/ and mach-pxa/ into the same mach-pxa + directory. The plat-pxa/ would therefore disappear. + +Credits +------- + + Maen Suleiman <maen@marvell.com> + Lior Amsalem <alior@marvell.com> + Thomas Petazzoni <thomas.petazzoni@free-electrons.com> + Andrew Lunn <andrew@lunn.ch> + Nicolas Pitre <nico@fluxnic.net> + Eric Miao <eric.y.miao@gmail.com> diff --git a/Documentation/arm/OMAP/DSS b/Documentation/arm/OMAP/DSS new file mode 100644 index 00000000000..4484e021290 --- /dev/null +++ b/Documentation/arm/OMAP/DSS @@ -0,0 +1,362 @@ +OMAP2/3 Display Subsystem +------------------------- + +This is an almost total rewrite of the OMAP FB driver in drivers/video/omap +(let's call it DSS1). The main differences between DSS1 and DSS2 are DSI, +TV-out and multiple display support, but there are lots of small improvements +also. + +The DSS2 driver (omapdss module) is in arch/arm/plat-omap/dss/, and the FB, +panel and controller drivers are in drivers/video/omap2/. DSS1 and DSS2 live +currently side by side, you can choose which one to use. + +Features +-------- + +Working and tested features include: + +- MIPI DPI (parallel) output +- MIPI DSI output in command mode +- MIPI DBI (RFBI) output +- SDI output +- TV output +- All pieces can be compiled as a module or inside kernel +- Use DISPC to update any of the outputs +- Use CPU to update RFBI or DSI output +- OMAP DISPC planes +- RGB16, RGB24 packed, RGB24 unpacked +- YUV2, UYVY +- Scaling +- Adjusting DSS FCK to find a good pixel clock +- Use DSI DPLL to create DSS FCK + +Tested boards include: +- OMAP3 SDP board +- Beagle board +- N810 + +omapdss driver +-------------- + +The DSS driver does not itself have any support for Linux framebuffer, V4L or +such like the current ones, but it has an internal kernel API that upper level +drivers can use. + +The DSS driver models OMAP's overlays, overlay managers and displays in a +flexible way to enable non-common multi-display configuration. In addition to +modelling the hardware overlays, omapdss supports virtual overlays and overlay +managers. These can be used when updating a display with CPU or system DMA. + +omapdss driver support for audio +-------------------------------- +There exist several display technologies and standards that support audio as +well. Hence, it is relevant to update the DSS device driver to provide an audio +interface that may be used by an audio driver or any other driver interested in +the functionality. + +The audio_enable function is intended to prepare the relevant +IP for playback (e.g., enabling an audio FIFO, taking in/out of reset +some IP, enabling companion chips, etc). It is intended to be called before +audio_start. The audio_disable function performs the reverse operation and is +intended to be called after audio_stop. + +While a given DSS device driver may support audio, it is possible that for +certain configurations audio is not supported (e.g., an HDMI display using a +VESA video timing). The audio_supported function is intended to query whether +the current configuration of the display supports audio. + +The audio_config function is intended to configure all the relevant audio +parameters of the display. In order to make the function independent of any +specific DSS device driver, a struct omap_dss_audio is defined. Its purpose +is to contain all the required parameters for audio configuration. At the +moment, such structure contains pointers to IEC-60958 channel status word +and CEA-861 audio infoframe structures. This should be enough to support +HDMI and DisplayPort, as both are based on CEA-861 and IEC-60958. + +The audio_enable/disable, audio_config and audio_supported functions could be +implemented as functions that may sleep. Hence, they should not be called +while holding a spinlock or a readlock. + +The audio_start/audio_stop function is intended to effectively start/stop audio +playback after the configuration has taken place. These functions are designed +to be used in an atomic context. Hence, audio_start should return quickly and be +called only after all the needed resources for audio playback (audio FIFOs, +DMA channels, companion chips, etc) have been enabled to begin data transfers. +audio_stop is designed to only stop the audio transfers. The resources used +for playback are released using audio_disable. + +The enum omap_dss_audio_state may be used to help the implementations of +the interface to keep track of the audio state. The initial state is _DISABLED; +then, the state transitions to _CONFIGURED, and then, when it is ready to +play audio, to _ENABLED. The state _PLAYING is used when the audio is being +rendered. + + +Panel and controller drivers +---------------------------- + +The drivers implement panel or controller specific functionality and are not +usually visible to users except through omapfb driver. They register +themselves to the DSS driver. + +omapfb driver +------------- + +The omapfb driver implements arbitrary number of standard linux framebuffers. +These framebuffers can be routed flexibly to any overlays, thus allowing very +dynamic display architecture. + +The driver exports some omapfb specific ioctls, which are compatible with the +ioctls in the old driver. + +The rest of the non standard features are exported via sysfs. Whether the final +implementation will use sysfs, or ioctls, is still open. + +V4L2 drivers +------------ + +V4L2 is being implemented in TI. + +From omapdss point of view the V4L2 drivers should be similar to framebuffer +driver. + +Architecture +-------------------- + +Some clarification what the different components do: + + - Framebuffer is a memory area inside OMAP's SRAM/SDRAM that contains the + pixel data for the image. Framebuffer has width and height and color + depth. + - Overlay defines where the pixels are read from and where they go on the + screen. The overlay may be smaller than framebuffer, thus displaying only + part of the framebuffer. The position of the overlay may be changed if + the overlay is smaller than the display. + - Overlay manager combines the overlays in to one image and feeds them to + display. + - Display is the actual physical display device. + +A framebuffer can be connected to multiple overlays to show the same pixel data +on all of the overlays. Note that in this case the overlay input sizes must be +the same, but, in case of video overlays, the output size can be different. Any +framebuffer can be connected to any overlay. + +An overlay can be connected to one overlay manager. Also DISPC overlays can be +connected only to DISPC overlay managers, and virtual overlays can be only +connected to virtual overlays. + +An overlay manager can be connected to one display. There are certain +restrictions which kinds of displays an overlay manager can be connected: + + - DISPC TV overlay manager can be only connected to TV display. + - Virtual overlay managers can only be connected to DBI or DSI displays. + - DISPC LCD overlay manager can be connected to all displays, except TV + display. + +Sysfs +----- +The sysfs interface is mainly used for testing. I don't think sysfs +interface is the best for this in the final version, but I don't quite know +what would be the best interfaces for these things. + +The sysfs interface is divided to two parts: DSS and FB. + +/sys/class/graphics/fb? directory: +mirror 0=off, 1=on +rotate Rotation 0-3 for 0, 90, 180, 270 degrees +rotate_type 0 = DMA rotation, 1 = VRFB rotation +overlays List of overlay numbers to which framebuffer pixels go +phys_addr Physical address of the framebuffer +virt_addr Virtual address of the framebuffer +size Size of the framebuffer + +/sys/devices/platform/omapdss/overlay? directory: +enabled 0=off, 1=on +input_size width,height (ie. the framebuffer size) +manager Destination overlay manager name +name +output_size width,height +position x,y +screen_width width +global_alpha global alpha 0-255 0=transparent 255=opaque + +/sys/devices/platform/omapdss/manager? directory: +display Destination display +name +alpha_blending_enabled 0=off, 1=on +trans_key_enabled 0=off, 1=on +trans_key_type gfx-destination, video-source +trans_key_value transparency color key (RGB24) +default_color default background color (RGB24) + +/sys/devices/platform/omapdss/display? directory: +ctrl_name Controller name +mirror 0=off, 1=on +update_mode 0=off, 1=auto, 2=manual +enabled 0=off, 1=on +name +rotate Rotation 0-3 for 0, 90, 180, 270 degrees +timings Display timings (pixclock,xres/hfp/hbp/hsw,yres/vfp/vbp/vsw) + When writing, two special timings are accepted for tv-out: + "pal" and "ntsc" +panel_name +tear_elim Tearing elimination 0=off, 1=on +output_type Output type (video encoder only): "composite" or "svideo" + +There are also some debugfs files at <debugfs>/omapdss/ which show information +about clocks and registers. + +Examples +-------- + +The following definitions have been made for the examples below: + +ovl0=/sys/devices/platform/omapdss/overlay0 +ovl1=/sys/devices/platform/omapdss/overlay1 +ovl2=/sys/devices/platform/omapdss/overlay2 + +mgr0=/sys/devices/platform/omapdss/manager0 +mgr1=/sys/devices/platform/omapdss/manager1 + +lcd=/sys/devices/platform/omapdss/display0 +dvi=/sys/devices/platform/omapdss/display1 +tv=/sys/devices/platform/omapdss/display2 + +fb0=/sys/class/graphics/fb0 +fb1=/sys/class/graphics/fb1 +fb2=/sys/class/graphics/fb2 + +Default setup on OMAP3 SDP +-------------------------- + +Here's the default setup on OMAP3 SDP board. All planes go to LCD. DVI +and TV-out are not in use. The columns from left to right are: +framebuffers, overlays, overlay managers, displays. Framebuffers are +handled by omapfb, and the rest by the DSS. + +FB0 --- GFX -\ DVI +FB1 --- VID1 --+- LCD ---- LCD +FB2 --- VID2 -/ TV ----- TV + +Example: Switch from LCD to DVI +---------------------- + +w=`cat $dvi/timings | cut -d "," -f 2 | cut -d "/" -f 1` +h=`cat $dvi/timings | cut -d "," -f 3 | cut -d "/" -f 1` + +echo "0" > $lcd/enabled +echo "" > $mgr0/display +fbset -fb /dev/fb0 -xres $w -yres $h -vxres $w -vyres $h +# at this point you have to switch the dvi/lcd dip-switch from the omap board +echo "dvi" > $mgr0/display +echo "1" > $dvi/enabled + +After this the configuration looks like: + +FB0 --- GFX -\ -- DVI +FB1 --- VID1 --+- LCD -/ LCD +FB2 --- VID2 -/ TV ----- TV + +Example: Clone GFX overlay to LCD and TV +------------------------------- + +w=`cat $tv/timings | cut -d "," -f 2 | cut -d "/" -f 1` +h=`cat $tv/timings | cut -d "," -f 3 | cut -d "/" -f 1` + +echo "0" > $ovl0/enabled +echo "0" > $ovl1/enabled + +echo "" > $fb1/overlays +echo "0,1" > $fb0/overlays + +echo "$w,$h" > $ovl1/output_size +echo "tv" > $ovl1/manager + +echo "1" > $ovl0/enabled +echo "1" > $ovl1/enabled + +echo "1" > $tv/enabled + +After this the configuration looks like (only relevant parts shown): + +FB0 +-- GFX ---- LCD ---- LCD + \- VID1 ---- TV ---- TV + +Misc notes +---------- + +OMAP FB allocates the framebuffer memory using the standard dma allocator. You +can enable Contiguous Memory Allocator (CONFIG_CMA) to improve the dma +allocator, and if CMA is enabled, you use "cma=" kernel parameter to increase +the global memory area for CMA. + +Using DSI DPLL to generate pixel clock it is possible produce the pixel clock +of 86.5MHz (max possible), and with that you get 1280x1024@57 output from DVI. + +Rotation and mirroring currently only supports RGB565 and RGB8888 modes. VRFB +does not support mirroring. + +VRFB rotation requires much more memory than non-rotated framebuffer, so you +probably need to increase your vram setting before using VRFB rotation. Also, +many applications may not work with VRFB if they do not pay attention to all +framebuffer parameters. + +Kernel boot arguments +--------------------- + +omapfb.mode=<display>:<mode>[,...] + - Default video mode for specified displays. For example, + "dvi:800x400MR-24@60". See drivers/video/modedb.c. + There are also two special modes: "pal" and "ntsc" that + can be used to tv out. + +omapfb.vram=<fbnum>:<size>[@<physaddr>][,...] + - VRAM allocated for a framebuffer. Normally omapfb allocates vram + depending on the display size. With this you can manually allocate + more or define the physical address of each framebuffer. For example, + "1:4M" to allocate 4M for fb1. + +omapfb.debug=<y|n> + - Enable debug printing. You have to have OMAPFB debug support enabled + in kernel config. + +omapfb.test=<y|n> + - Draw test pattern to framebuffer whenever framebuffer settings change. + You need to have OMAPFB debug support enabled in kernel config. + +omapfb.vrfb=<y|n> + - Use VRFB rotation for all framebuffers. + +omapfb.rotate=<angle> + - Default rotation applied to all framebuffers. + 0 - 0 degree rotation + 1 - 90 degree rotation + 2 - 180 degree rotation + 3 - 270 degree rotation + +omapfb.mirror=<y|n> + - Default mirror for all framebuffers. Only works with DMA rotation. + +omapdss.def_disp=<display> + - Name of default display, to which all overlays will be connected. + Common examples are "lcd" or "tv". + +omapdss.debug=<y|n> + - Enable debug printing. You have to have DSS debug support enabled in + kernel config. + +TODO +---- + +DSS locking + +Error checking +- Lots of checks are missing or implemented just as BUG() + +System DMA update for DSI +- Can be used for RGB16 and RGB24P modes. Probably not for RGB24U (how + to skip the empty byte?) + +OMAP1 support +- Not sure if needed + diff --git a/Documentation/arm/OMAP/omap_pm b/Documentation/arm/OMAP/omap_pm new file mode 100644 index 00000000000..4ae915a9f89 --- /dev/null +++ b/Documentation/arm/OMAP/omap_pm @@ -0,0 +1,154 @@ + +The OMAP PM interface +===================== + +This document describes the temporary OMAP PM interface. Driver +authors use these functions to communicate minimum latency or +throughput constraints to the kernel power management code. +Over time, the intention is to merge features from the OMAP PM +interface into the Linux PM QoS code. + +Drivers need to express PM parameters which: + +- support the range of power management parameters present in the TI SRF; + +- separate the drivers from the underlying PM parameter + implementation, whether it is the TI SRF or Linux PM QoS or Linux + latency framework or something else; + +- specify PM parameters in terms of fundamental units, such as + latency and throughput, rather than units which are specific to OMAP + or to particular OMAP variants; + +- allow drivers which are shared with other architectures (e.g., + DaVinci) to add these constraints in a way which won't affect non-OMAP + systems, + +- can be implemented immediately with minimal disruption of other + architectures. + + +This document proposes the OMAP PM interface, including the following +five power management functions for driver code: + +1. Set the maximum MPU wakeup latency: + (*pdata->set_max_mpu_wakeup_lat)(struct device *dev, unsigned long t) + +2. Set the maximum device wakeup latency: + (*pdata->set_max_dev_wakeup_lat)(struct device *dev, unsigned long t) + +3. Set the maximum system DMA transfer start latency (CORE pwrdm): + (*pdata->set_max_sdma_lat)(struct device *dev, long t) + +4. Set the minimum bus throughput needed by a device: + (*pdata->set_min_bus_tput)(struct device *dev, u8 agent_id, unsigned long r) + +5. Return the number of times the device has lost context + (*pdata->get_dev_context_loss_count)(struct device *dev) + + +Further documentation for all OMAP PM interface functions can be +found in arch/arm/plat-omap/include/mach/omap-pm.h. + + +The OMAP PM layer is intended to be temporary +--------------------------------------------- + +The intention is that eventually the Linux PM QoS layer should support +the range of power management features present in OMAP3. As this +happens, existing drivers using the OMAP PM interface can be modified +to use the Linux PM QoS code; and the OMAP PM interface can disappear. + + +Driver usage of the OMAP PM functions +------------------------------------- + +As the 'pdata' in the above examples indicates, these functions are +exposed to drivers through function pointers in driver .platform_data +structures. The function pointers are initialized by the board-*.c +files to point to the corresponding OMAP PM functions: +.set_max_dev_wakeup_lat will point to +omap_pm_set_max_dev_wakeup_lat(), etc. Other architectures which do +not support these functions should leave these function pointers set +to NULL. Drivers should use the following idiom: + + if (pdata->set_max_dev_wakeup_lat) + (*pdata->set_max_dev_wakeup_lat)(dev, t); + +The most common usage of these functions will probably be to specify +the maximum time from when an interrupt occurs, to when the device +becomes accessible. To accomplish this, driver writers should use the +set_max_mpu_wakeup_lat() function to constrain the MPU wakeup +latency, and the set_max_dev_wakeup_lat() function to constrain the +device wakeup latency (from clk_enable() to accessibility). For +example, + + /* Limit MPU wakeup latency */ + if (pdata->set_max_mpu_wakeup_lat) + (*pdata->set_max_mpu_wakeup_lat)(dev, tc); + + /* Limit device powerdomain wakeup latency */ + if (pdata->set_max_dev_wakeup_lat) + (*pdata->set_max_dev_wakeup_lat)(dev, td); + + /* total wakeup latency in this example: (tc + td) */ + +The PM parameters can be overwritten by calling the function again +with the new value. The settings can be removed by calling the +function with a t argument of -1 (except in the case of +set_max_bus_tput(), which should be called with an r argument of 0). + +The fifth function above, omap_pm_get_dev_context_loss_count(), +is intended as an optimization to allow drivers to determine whether the +device has lost its internal context. If context has been lost, the +driver must restore its internal context before proceeding. + + +Other specialized interface functions +------------------------------------- + +The five functions listed above are intended to be usable by any +device driver. DSPBridge and CPUFreq have a few special requirements. +DSPBridge expresses target DSP performance levels in terms of OPP IDs. +CPUFreq expresses target MPU performance levels in terms of MPU +frequency. The OMAP PM interface contains functions for these +specialized cases to convert that input information (OPPs/MPU +frequency) into the form that the underlying power management +implementation needs: + +6. (*pdata->dsp_get_opp_table)(void) + +7. (*pdata->dsp_set_min_opp)(u8 opp_id) + +8. (*pdata->dsp_get_opp)(void) + +9. (*pdata->cpu_get_freq_table)(void) + +10. (*pdata->cpu_set_freq)(unsigned long f) + +11. (*pdata->cpu_get_freq)(void) + +Customizing OPP for platform +============================ +Defining CONFIG_PM should enable OPP layer for the silicon +and the registration of OPP table should take place automatically. +However, in special cases, the default OPP table may need to be +tweaked, for e.g.: + * enable default OPPs which are disabled by default, but which + could be enabled on a platform + * Disable an unsupported OPP on the platform + * Define and add a custom opp table entry +in these cases, the board file needs to do additional steps as follows: +arch/arm/mach-omapx/board-xyz.c + #include "pm.h" + .... + static void __init omap_xyz_init_irq(void) + { + .... + /* Initialize the default table */ + omapx_opp_init(); + /* Do customization to the defaults */ + .... + } +NOTE: omapx_opp_init will be omap3_opp_init or as required +based on the omap family. diff --git a/Documentation/arm/README b/Documentation/arm/README index 9b9c8226fdc..aea34095cdc 100644 --- a/Documentation/arm/README +++ b/Documentation/arm/README @@ -41,12 +41,12 @@ Bug reports etc --------------- Please send patches to the patch system. For more information, see - http://www.arm.linux.org.uk/patches/info.html Always include some + http://www.arm.linux.org.uk/developer/patches/info.php Always include some explanation as to what the patch does and why it is needed. Bug reports should be sent to linux-arm-kernel@lists.arm.linux.org.uk, or submitted through the web form at - http://www.arm.linux.org.uk/forms/solution.shtml + http://www.arm.linux.org.uk/developer/ When sending bug reports, please ensure that they contain all relevant information, eg. the kernel messages that were printed before/during @@ -79,7 +79,7 @@ Machine/Platform support To this end, we now have arch/arm/mach-$(MACHINE) directories which are designed to house the non-driver files for a particular machine (eg, PCI, memory management, architecture definitions etc). For all future - machines, there should be a corresponding include/asm-arm/arch-$(MACHINE) + machines, there should be a corresponding arch/arm/mach-$(MACHINE)/include/mach directory. @@ -176,7 +176,7 @@ Kernel entry (head.S) class typically based around one or more system on a chip devices, and acts as a natural container around the actual implementations. These classes are given directories - arch/arm/mach-<class> and - include/asm-arm/arch-<class> - which contain the source files to + arch/arm/mach-<class> - which contain the source files to/include/mach support the machine class. This directories also contain any machine specific supporting code. diff --git a/Documentation/arm/SA1100/ADSBitsy b/Documentation/arm/SA1100/ADSBitsy index ab47c383390..f9f62e8c071 100644 --- a/Documentation/arm/SA1100/ADSBitsy +++ b/Documentation/arm/SA1100/ADSBitsy @@ -32,7 +32,7 @@ Notes: - The flash on board is divided into 3 partitions. You should be careful to use flash on board. - It's partition is different from GraphicsClient Plus and GraphicsMaster + Its partition is different from GraphicsClient Plus and GraphicsMaster - 16bpp mode requires a different cable than what ships with the board. Contact ADS or look through the manual to wire your own. Currently, @@ -40,4 +40,4 @@ Notes: mode, the timing is off so the image is corrupted. This will be fixed soon. -Any contribution can be sent to nico@cam.org and will be greatly welcome! +Any contribution can be sent to nico@fluxnic.net and will be greatly welcome! diff --git a/Documentation/arm/SA1100/Assabet b/Documentation/arm/SA1100/Assabet index 78bc1c1b04e..08b885d3567 100644 --- a/Documentation/arm/SA1100/Assabet +++ b/Documentation/arm/SA1100/Assabet @@ -2,8 +2,7 @@ The Intel Assabet (SA-1110 evaluation) board ============================================ Please see: -http://developer.intel.com/design/strong/quicklist/eval-plat/sa-1110.htm -http://developer.intel.com/design/strong/guides/278278.htm +http://developer.intel.com Also some notes from John G Dorsey <jd5q@andrew.cmu.edu>: http://www.cs.cmu.edu/~wearable/software/assabet.html @@ -64,7 +63,7 @@ Initial RedBoot configuration ----------------------------- The commands used here are explained in The RedBoot User's Guide available -on-line at http://sources.redhat.com/ecos/docs-latest/redboot/redboot.html. +on-line at http://sources.redhat.com/ecos/docs.html. Please refer to it for explanations. If you have a CF network card (my Assabet kit contained a CF+ LP-E from @@ -240,7 +239,7 @@ Then, rebooting the Assabet is just a matter of waiting for the login prompt. Nicolas Pitre -nico@cam.org +nico@fluxnic.net June 12, 2001 diff --git a/Documentation/arm/SA1100/Brutus b/Documentation/arm/SA1100/Brutus index 2254c8f0b32..6a3aa95e9bf 100644 --- a/Documentation/arm/SA1100/Brutus +++ b/Documentation/arm/SA1100/Brutus @@ -1,7 +1,7 @@ Brutus is an evaluation platform for the SA1100 manufactured by Intel. For more details, see: -http://developer.intel.com/design/strong/applnots/sa1100lx/getstart.htm +http://developer.intel.com To compile for Brutus, you must issue the following commands: @@ -60,7 +60,7 @@ little modifications. Any contribution is welcome. -Please send patches to nico@cam.org +Please send patches to nico@fluxnic.net Have Fun ! diff --git a/Documentation/arm/SA1100/FreeBird b/Documentation/arm/SA1100/FreeBird index eda28b3232e..ab9193663b2 100644 --- a/Documentation/arm/SA1100/FreeBird +++ b/Documentation/arm/SA1100/FreeBird @@ -1,6 +1,6 @@ -Freebird-1.1 is produced by Legned(C) ,Inc. -(http://www.legend.com.cn) -and software/linux mainatined by Coventive(C),Inc. +Freebird-1.1 is produced by Legend(C), Inc. +http://web.archive.org/web/*/http://www.legend.com.cn +and software/linux maintained by Coventive(C), Inc. (http://www.coventive.com) Based on the Nicolas's strongarm kernel tree. diff --git a/Documentation/arm/SA1100/GraphicsClient b/Documentation/arm/SA1100/GraphicsClient index 8fa7e8027ff..867bb35943a 100644 --- a/Documentation/arm/SA1100/GraphicsClient +++ b/Documentation/arm/SA1100/GraphicsClient @@ -4,7 +4,7 @@ For more details, contact Applied Data Systems or see http://www.applieddata.net/products.html The original Linux support for this product has been provided by -Nicolas Pitre <nico@cam.org>. Continued development work by +Nicolas Pitre <nico@fluxnic.net>. Continued development work by Woojung Huh <whuh@applieddata.net> It's currently possible to mount a root filesystem via NFS providing a @@ -71,7 +71,7 @@ Supported peripherals: - serial ports (ttyS[0-2]) - ttyS0 is default for serial console - Smart I/O (ADC, keypad, digital inputs, etc) - See http://www.applieddata.com/developers/linux for IOCTL documentation + See http://www.eurotech-inc.com/linux-sbc.asp for IOCTL documentation and example user space code. ps/2 keybd is multiplexed through this driver To do: @@ -94,5 +94,5 @@ Notes: mode, the timing is off so the image is corrupted. This will be fixed soon. -Any contribution can be sent to nico@cam.org and will be greatly welcome! +Any contribution can be sent to nico@fluxnic.net and will be greatly welcome! diff --git a/Documentation/arm/SA1100/GraphicsMaster b/Documentation/arm/SA1100/GraphicsMaster index dd28745ac52..9145088a0ba 100644 --- a/Documentation/arm/SA1100/GraphicsMaster +++ b/Documentation/arm/SA1100/GraphicsMaster @@ -4,7 +4,7 @@ For more details, contact Applied Data Systems or see http://www.applieddata.net/products.html The original Linux support for this product has been provided by -Nicolas Pitre <nico@cam.org>. Continued development work by +Nicolas Pitre <nico@fluxnic.net>. Continued development work by Woojung Huh <whuh@applieddata.net> Use 'make graphicsmaster_config' before any 'make config'. @@ -28,7 +28,7 @@ Supported peripherals: - serial ports (ttyS[0-2]) - ttyS0 is default for serial console - Smart I/O (ADC, keypad, digital inputs, etc) - See http://www.applieddata.com/developers/linux for IOCTL documentation + See http://www.eurotech-inc.com/linux-sbc.asp for IOCTL documentation and example user space code. ps/2 keybd is multiplexed through this driver To do: @@ -50,4 +50,4 @@ Notes: mode, the timing is off so the image is corrupted. This will be fixed soon. -Any contribution can be sent to nico@cam.org and will be greatly welcome! +Any contribution can be sent to nico@fluxnic.net and will be greatly welcome! diff --git a/Documentation/arm/SA1100/Itsy b/Documentation/arm/SA1100/Itsy index 3b594534323..44b94997fa0 100644 --- a/Documentation/arm/SA1100/Itsy +++ b/Documentation/arm/SA1100/Itsy @@ -4,7 +4,7 @@ research projects at Compaq that are related to pocket computing. For more information, see: - http://www.research.digital.com/wrl/itsy/index.html + http://www.hpl.hp.com/downloads/crl/itsy/ Notes on initial 2.4 Itsy support (8/27/2000) : The port was done on an Itsy version 1.5 machine with a daughtercard with diff --git a/Documentation/arm/SA1100/PLEB b/Documentation/arm/SA1100/PLEB index 92cae066908..b9c8a631a35 100644 --- a/Documentation/arm/SA1100/PLEB +++ b/Documentation/arm/SA1100/PLEB @@ -6,6 +6,6 @@ PLEB support has yet to be fully integrated. For more information, see: - http://www.cse.unsw.edu.au/~pleb/ + http://www.cse.unsw.edu.au diff --git a/Documentation/arm/SA1100/Victor b/Documentation/arm/SA1100/Victor index 01e81fc4946..9cff415da5a 100644 --- a/Documentation/arm/SA1100/Victor +++ b/Documentation/arm/SA1100/Victor @@ -3,13 +3,13 @@ VisuAide, Inc. to be used by blind people. For more information related to Victor, see: - http://www.visuaide.com/victor + http://www.humanware.com/en-usa/products Of course Victor is using Linux as its main operating system. The Victor implementation for Linux is maintained by Nicolas Pitre: nico@visuaide.com - nico@cam.org + nico@fluxnic.net For any comments, please feel free to contact me through the above addresses. diff --git a/Documentation/arm/SA1100/nanoEngine b/Documentation/arm/SA1100/nanoEngine index fc431cbfefc..48a7934f95f 100644 --- a/Documentation/arm/SA1100/nanoEngine +++ b/Documentation/arm/SA1100/nanoEngine @@ -7,5 +7,5 @@ for more info. (Ref: Stuart Adams <sja@brightstareng.com>) Also visit Larry Doolittle's "Linux for the nanoEngine" site: -http://recycle.lbl.gov/~ldoolitt/bse/ +http://www.brightstareng.com/arm/nanoeng.htm diff --git a/Documentation/arm/SA1100/serial_UART b/Documentation/arm/SA1100/serial_UART index aea2e91ca0e..a63966f1d08 100644 --- a/Documentation/arm/SA1100/serial_UART +++ b/Documentation/arm/SA1100/serial_UART @@ -24,8 +24,8 @@ The SA1100 serial port had its major/minor numbers officially assigned: > 7 = /dev/cusa2 Callout device for ttySA2 > -If you're not using devfs, you must create those inodes in /dev -on the root filesystem used by your SA1100-based device: +You must create those inodes in /dev on the root filesystem used +by your SA1100-based device: mknod ttySA0 c 204 5 mknod ttySA1 c 204 6 diff --git a/Documentation/arm/SH-Mobile/Makefile b/Documentation/arm/SH-Mobile/Makefile new file mode 100644 index 00000000000..8771d832cf8 --- /dev/null +++ b/Documentation/arm/SH-Mobile/Makefile @@ -0,0 +1,8 @@ +BIN := vrl4 + +.PHONY: all +all: $(BIN) + +.PHONY: clean +clean: + rm -f *.o $(BIN) diff --git a/Documentation/arm/SH-Mobile/vrl4.c b/Documentation/arm/SH-Mobile/vrl4.c new file mode 100644 index 00000000000..e8a191358ad --- /dev/null +++ b/Documentation/arm/SH-Mobile/vrl4.c @@ -0,0 +1,169 @@ +/* + * vrl4 format generator + * + * Copyright (C) 2010 Simon Horman + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +/* + * usage: vrl4 < zImage > out + * dd if=out of=/dev/sdx bs=512 seek=1 # Write the image to sector 1 + * + * Reads a zImage from stdin and writes a vrl4 image to stdout. + * In practice this means writing a padded vrl4 header to stdout followed + * by the zImage. + * + * The padding places the zImage at ALIGN bytes into the output. + * The vrl4 uses ALIGN + START_BASE as the start_address. + * This is where the mask ROM will jump to after verifying the header. + * + * The header sets copy_size to min(sizeof(zImage), MAX_BOOT_PROG_LEN) + ALIGN. + * That is, the mask ROM will load the padded header (ALIGN bytes) + * And then MAX_BOOT_PROG_LEN bytes of the image, or the entire image, + * whichever is smaller. + * + * The zImage is not modified in any way. + */ + +#define _BSD_SOURCE +#include <endian.h> +#include <unistd.h> +#include <stdint.h> +#include <stdio.h> +#include <errno.h> + +struct hdr { + uint32_t magic1; + uint32_t reserved1; + uint32_t magic2; + uint32_t reserved2; + uint16_t copy_size; + uint16_t boot_options; + uint32_t reserved3; + uint32_t start_address; + uint32_t reserved4; + uint32_t reserved5; + char reserved6[308]; +}; + +#define DECLARE_HDR(h) \ + struct hdr (h) = { \ + .magic1 = htole32(0xea000000), \ + .reserved1 = htole32(0x56), \ + .magic2 = htole32(0xe59ff008), \ + .reserved3 = htole16(0x1) } + +/* Align to 512 bytes, the MMCIF sector size */ +#define ALIGN_BITS 9 +#define ALIGN (1 << ALIGN_BITS) + +#define START_BASE 0xe55b0000 + +/* + * With an alignment of 512 the header uses the first sector. + * There is a 128 sector (64kbyte) limit on the data loaded by the mask ROM. + * So there are 127 sectors left for the boot programme. But in practice + * Only a small portion of a zImage is needed, 16 sectors should be more + * than enough. + * + * Note that this sets how much of the zImage is copied by the mask ROM. + * The entire zImage is present after the header and is loaded + * by the code in the boot program (which is the first portion of the zImage). + */ +#define MAX_BOOT_PROG_LEN (16 * 512) + +#define ROUND_UP(x) ((x + ALIGN - 1) & ~(ALIGN - 1)) + +ssize_t do_read(int fd, void *buf, size_t count) +{ + size_t offset = 0; + ssize_t l; + + while (offset < count) { + l = read(fd, buf + offset, count - offset); + if (!l) + break; + if (l < 0) { + if (errno == EAGAIN || errno == EWOULDBLOCK) + continue; + perror("read"); + return -1; + } + offset += l; + } + + return offset; +} + +ssize_t do_write(int fd, const void *buf, size_t count) +{ + size_t offset = 0; + ssize_t l; + + while (offset < count) { + l = write(fd, buf + offset, count - offset); + if (l < 0) { + if (errno == EAGAIN || errno == EWOULDBLOCK) + continue; + perror("write"); + return -1; + } + offset += l; + } + + return offset; +} + +ssize_t write_zero(int fd, size_t len) +{ + size_t i = len; + + while (i--) { + const char x = 0; + if (do_write(fd, &x, 1) < 0) + return -1; + } + + return len; +} + +int main(void) +{ + DECLARE_HDR(hdr); + char boot_program[MAX_BOOT_PROG_LEN]; + size_t aligned_hdr_len, alligned_prog_len; + ssize_t prog_len; + + prog_len = do_read(0, boot_program, sizeof(boot_program)); + if (prog_len <= 0) + return -1; + + aligned_hdr_len = ROUND_UP(sizeof(hdr)); + hdr.start_address = htole32(START_BASE + aligned_hdr_len); + alligned_prog_len = ROUND_UP(prog_len); + hdr.copy_size = htole16(aligned_hdr_len + alligned_prog_len); + + if (do_write(1, &hdr, sizeof(hdr)) < 0) + return -1; + if (write_zero(1, aligned_hdr_len - sizeof(hdr)) < 0) + return -1; + + if (do_write(1, boot_program, prog_len) < 0) + return 1; + + /* Write out the rest of the kernel */ + while (1) { + prog_len = do_read(0, boot_program, sizeof(boot_program)); + if (prog_len < 0) + return 1; + if (prog_len == 0) + break; + if (do_write(1, boot_program, prog_len) < 0) + return 1; + } + + return 0; +} diff --git a/Documentation/arm/SH-Mobile/zboot-rom-mmcif.txt b/Documentation/arm/SH-Mobile/zboot-rom-mmcif.txt new file mode 100644 index 00000000000..efff8ae2713 --- /dev/null +++ b/Documentation/arm/SH-Mobile/zboot-rom-mmcif.txt @@ -0,0 +1,29 @@ +ROM-able zImage boot from MMC +----------------------------- + +An ROM-able zImage compiled with ZBOOT_ROM_MMCIF may be written to MMC and +SuperH Mobile ARM will to boot directly from the MMCIF hardware block. + +This is achieved by the mask ROM loading the first portion of the image into +MERAM and then jumping to it. This portion contains loader code which +copies the entire image to SDRAM and jumps to it. From there the zImage +boot code proceeds as normal, uncompressing the image into its final +location and then jumping to it. + +This code has been tested on an AP4EB board using the developer 1A eMMC +boot mode which is configured using the following jumper settings. +The board used for testing required a patched mask ROM in order for +this mode to function. + + 8 7 6 5 4 3 2 1 + x|x|x|x|x| |x| +S4 -+-+-+-+-+-+-+- + | | | | |x| |x on + +The zImage must be written to the MMC card at sector 1 (512 bytes) in +vrl4 format. A utility vrl4 is supplied to accomplish this. + +e.g. + vrl4 < zImage | dd of=/dev/sdX bs=512 seek=1 + +A dual-voltage MMC 4.0 card was used for testing. diff --git a/Documentation/arm/SH-Mobile/zboot-rom-sdhi.txt b/Documentation/arm/SH-Mobile/zboot-rom-sdhi.txt new file mode 100644 index 00000000000..441959846e1 --- /dev/null +++ b/Documentation/arm/SH-Mobile/zboot-rom-sdhi.txt @@ -0,0 +1,42 @@ +ROM-able zImage boot from eSD +----------------------------- + +An ROM-able zImage compiled with ZBOOT_ROM_SDHI may be written to eSD and +SuperH Mobile ARM will to boot directly from the SDHI hardware block. + +This is achieved by the mask ROM loading the first portion of the image into +MERAM and then jumping to it. This portion contains loader code which +copies the entire image to SDRAM and jumps to it. From there the zImage +boot code proceeds as normal, uncompressing the image into its final +location and then jumping to it. + +This code has been tested on an mackerel board using the developer 1A eSD +boot mode which is configured using the following jumper settings. + + 8 7 6 5 4 3 2 1 + x|x|x|x| |x|x| +S4 -+-+-+-+-+-+-+- + | | | |x| | |x on + +The eSD card needs to be present in SDHI slot 1 (CN7). +As such S1 and S33 also need to be configured as per +the notes in arch/arm/mach-shmobile/board-mackerel.c. + +A partial zImage must be written to physical partition #1 (boot) +of the eSD at sector 0 in vrl4 format. A utility vrl4 is supplied to +accomplish this. + +e.g. + vrl4 < zImage | dd of=/dev/sdX bs=512 count=17 + +A full copy of _the same_ zImage should be written to physical partition #1 +(boot) of the eSD at sector 0. This should _not_ be in vrl4 format. + + vrl4 < zImage | dd of=/dev/sdX bs=512 + +Note: The commands above assume that the physical partition has been +switched. No such facility currently exists in the Linux Kernel. + +Physical partitions are described in the eSD specification. At the time of +writing they are not the same as partitions that are typically configured +using fdisk and visible through /proc/partitions diff --git a/Documentation/arm/SPEAr/overview.txt b/Documentation/arm/SPEAr/overview.txt new file mode 100644 index 00000000000..65610bf52eb --- /dev/null +++ b/Documentation/arm/SPEAr/overview.txt @@ -0,0 +1,63 @@ + SPEAr ARM Linux Overview + ========================== + +Introduction +------------ + + SPEAr (Structured Processor Enhanced Architecture). + weblink : http://www.st.com/spear + + The ST Microelectronics SPEAr range of ARM9/CortexA9 System-on-Chip CPUs are + supported by the 'spear' platform of ARM Linux. Currently SPEAr1310, + SPEAr1340, SPEAr300, SPEAr310, SPEAr320 and SPEAr600 SOCs are supported. + + Hierarchy in SPEAr is as follows: + + SPEAr (Platform) + - SPEAr3XX (3XX SOC series, based on ARM9) + - SPEAr300 (SOC) + - SPEAr300 Evaluation Board + - SPEAr310 (SOC) + - SPEAr310 Evaluation Board + - SPEAr320 (SOC) + - SPEAr320 Evaluation Board + - SPEAr6XX (6XX SOC series, based on ARM9) + - SPEAr600 (SOC) + - SPEAr600 Evaluation Board + - SPEAr13XX (13XX SOC series, based on ARM CORTEXA9) + - SPEAr1310 (SOC) + - SPEAr1310 Evaluation Board + - SPEAr1340 (SOC) + - SPEAr1340 Evaluation Board + + Configuration + ------------- + + A generic configuration is provided for each machine, and can be used as the + default by + make spear13xx_defconfig + make spear3xx_defconfig + make spear6xx_defconfig + + Layout + ------ + + The common files for multiple machine families (SPEAr3xx, SPEAr6xx and + SPEAr13xx) are located in the platform code contained in arch/arm/plat-spear + with headers in plat/. + + Each machine series have a directory with name arch/arm/mach-spear followed by + series name. Like mach-spear3xx, mach-spear6xx and mach-spear13xx. + + Common file for machines of spear3xx family is mach-spear3xx/spear3xx.c, for + spear6xx is mach-spear6xx/spear6xx.c and for spear13xx family is + mach-spear13xx/spear13xx.c. mach-spear* also contain soc/machine specific + files, like spear1310.c, spear1340.c spear300.c, spear310.c, spear320.c and + spear600.c. mach-spear* doesn't contains board specific files as they fully + support Flattened Device Tree. + + + Document Author + --------------- + + Viresh Kumar <viresh.linux@gmail.com>, (c) 2010-2012 ST Microelectronics diff --git a/Documentation/arm/Samsung-S3C24XX/CPUfreq.txt b/Documentation/arm/Samsung-S3C24XX/CPUfreq.txt new file mode 100644 index 00000000000..fa968aa99d6 --- /dev/null +++ b/Documentation/arm/Samsung-S3C24XX/CPUfreq.txt @@ -0,0 +1,75 @@ + S3C24XX CPUfreq support + ======================= + +Introduction +------------ + + The S3C24XX series support a number of power saving systems, such as + the ability to change the core, memory and peripheral operating + frequencies. The core control is exported via the CPUFreq driver + which has a number of different manual or automatic controls over the + rate the core is running at. + + There are two forms of the driver depending on the specific CPU and + how the clocks are arranged. The first implementation used as single + PLL to feed the ARM, memory and peripherals via a series of dividers + and muxes and this is the implementation that is documented here. A + newer version where there is a separate PLL and clock divider for the + ARM core is available as a separate driver. + + +Layout +------ + + The code core manages the CPU specific drivers, any data that they + need to register and the interface to the generic drivers/cpufreq + system. Each CPU registers a driver to control the PLL, clock dividers + and anything else associated with it. Any board that wants to use this + framework needs to supply at least basic details of what is required. + + The core registers with drivers/cpufreq at init time if all the data + necessary has been supplied. + + +CPU support +----------- + + The support for each CPU depends on the facilities provided by the + SoC and the driver as each device has different PLL and clock chains + associated with it. + + +Slow Mode +--------- + + The SLOW mode where the PLL is turned off altogether and the + system is fed by the external crystal input is currently not + supported. + + +sysfs +----- + + The core code exports extra information via sysfs in the directory + devices/system/cpu/cpu0/arch-freq. + + +Board Support +------------- + + Each board that wants to use the cpufreq code must register some basic + information with the core driver to provide information about what the + board requires and any restrictions being placed on it. + + The board needs to supply information about whether it needs the IO bank + timings changing, any maximum frequency limits and information about the + SDRAM refresh rate. + + + + +Document Author +--------------- + +Ben Dooks, Copyright 2009 Simtec Electronics +Licensed under GPLv2 diff --git a/Documentation/arm/Samsung-S3C24XX/DMA.txt b/Documentation/arm/Samsung-S3C24XX/DMA.txt new file mode 100644 index 00000000000..3ed82383efe --- /dev/null +++ b/Documentation/arm/Samsung-S3C24XX/DMA.txt @@ -0,0 +1,46 @@ + S3C2410 DMA + =========== + +Introduction +------------ + + The kernel provides an interface to manage DMA transfers + using the DMA channels in the CPU, so that the central + duty of managing channel mappings, and programming the + channel generators is in one place. + + +DMA Channel Ordering +-------------------- + + Many of the range do not have connections for the DMA + channels to all sources, which means that some devices + have a restricted number of channels that can be used. + + To allow flexibility for each CPU type and board, the + DMA code can be given a DMA ordering structure which + allows the order of channel search to be specified, as + well as allowing the prohibition of certain claims. + + struct s3c24xx_dma_order has a list of channels, and + each channel within has a slot for a list of DMA + channel numbers. The slots are searched in order for + the presence of a DMA channel number with DMA_CH_VALID + or-ed in. + + If the order has the flag DMA_CH_NEVER set, then after + checking the channel list, the system will return no + found channel, thus denying the request. + + A board support file can call s3c24xx_dma_order_set() + to register a complete ordering set. The routine will + copy the data, so the original can be discarded with + __initdata. + + +Authour +------- + +Ben Dooks, +Copyright (c) 2007 Ben Dooks, Simtec Electronics +Licensed under the GPL v2 diff --git a/Documentation/arm/Samsung-S3C24XX/EB2410ITX.txt b/Documentation/arm/Samsung-S3C24XX/EB2410ITX.txt index 000e3d7a78b..b87292e05f2 100644 --- a/Documentation/arm/Samsung-S3C24XX/EB2410ITX.txt +++ b/Documentation/arm/Samsung-S3C24XX/EB2410ITX.txt @@ -38,7 +38,7 @@ MTD --- The NAND and NOR support has been merged from the linux-mtd project. - Any prolbems, see http://www.linux-mtd.infradead.org/ for more + Any problems, see http://www.linux-mtd.infradead.org/ for more information or up-to-date versions of linux-mtd. @@ -55,4 +55,4 @@ Maintainers This board is maintained by Simtec Electronics. -(c) 2004 Ben Dooks, Simtec Electronics +Copyright 2004 Ben Dooks, Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/GPIO.txt b/Documentation/arm/Samsung-S3C24XX/GPIO.txt index 0822764ec27..0ebd7e2244d 100644 --- a/Documentation/arm/Samsung-S3C24XX/GPIO.txt +++ b/Documentation/arm/Samsung-S3C24XX/GPIO.txt @@ -1,4 +1,4 @@ - S3C2410 GPIO Control + S3C24XX GPIO Control ==================== Introduction @@ -12,33 +12,96 @@ Introduction of the s3c2410 GPIO system, please read the Samsung provided data-sheet/users manual to find out the complete list. + See Documentation/arm/Samsung/GPIO.txt for the core implementation. -Headers + +GPIOLIB ------- - See include/asm-arm/arch-s3c2410/regs-gpio.h for the list - of GPIO pins, and the configuration values for them. This - is included by using #include <asm/arch/regs-gpio.h> + With the event of the GPIOLIB in drivers/gpio, support for some + of the GPIO functions such as reading and writing a pin will + be removed in favour of this common access method. + + Once all the extant drivers have been converted, the functions + listed below will be removed (they may be marked as __deprecated + in the near future). + + The following functions now either have a s3c_ specific variant + or are merged into gpiolib. See the definitions in + arch/arm/plat-samsung/include/plat/gpio-cfg.h: + + s3c2410_gpio_setpin() gpio_set_value() or gpio_direction_output() + s3c2410_gpio_getpin() gpio_get_value() or gpio_direction_input() + s3c2410_gpio_getirq() gpio_to_irq() + s3c2410_gpio_cfgpin() s3c_gpio_cfgpin() + s3c2410_gpio_getcfg() s3c_gpio_getcfg() + s3c2410_gpio_pullup() s3c_gpio_setpull() + + +GPIOLIB conversion +------------------ + +If you need to convert your board or driver to use gpiolib from the phased +out s3c2410 API, then here are some notes on the process. + +1) If your board is exclusively using an GPIO, say to control peripheral + power, then it will require to claim the gpio with gpio_request() before + it can use it. + + It is recommended to check the return value, with at least WARN_ON() + during initialisation. + +2) The s3c2410_gpio_cfgpin() can be directly replaced with s3c_gpio_cfgpin() + as they have the same arguments, and can either take the pin specific + values, or the more generic special-function-number arguments. + +3) s3c2410_gpio_pullup() changes have the problem that whilst the + s3c2410_gpio_pullup(x, 1) can be easily translated to the + s3c_gpio_setpull(x, S3C_GPIO_PULL_NONE), the s3c2410_gpio_pullup(x, 0) + are not so easy. + + The s3c2410_gpio_pullup(x, 0) case enables the pull-up (or in the case + of some of the devices, a pull-down) and as such the new API distinguishes + between the UP and DOWN case. There is currently no 'just turn on' setting + which may be required if this becomes a problem. + +4) s3c2410_gpio_setpin() can be replaced by gpio_set_value(), the old call + does not implicitly configure the relevant gpio to output. The gpio + direction should be changed before using gpio_set_value(). - The GPIO management functions are defined in the hardware - header include/asm-arm/arch-s3c2410/hardware.h which can be - included by #include <asm/arch/hardware.h> +5) s3c2410_gpio_getpin() is replaceable by gpio_get_value() if the pin + has been set to input. It is currently unknown what the behaviour is + when using gpio_get_value() on an output pin (s3c2410_gpio_getpin + would return the value the pin is supposed to be outputting). - A useful ammount of documentation can be found in the hardware - header on how the GPIO functions (and others) work. +6) s3c2410_gpio_getirq() should be directly replaceable with the + gpio_to_irq() call. - Whilst a number of these functions do make some checks on what - is passed to them, for speed of use, they may not always ensure - that the user supplied data to them is correct. +The s3c2410_gpio and gpio_ calls have always operated on the same gpio +numberspace, so there is no problem with converting the gpio numbering +between the calls. + + +Headers +------- + + See arch/arm/mach-s3c24xx/include/mach/regs-gpio.h for the list + of GPIO pins, and the configuration values for them. This + is included by using #include <mach/regs-gpio.h> PIN Numbers ----------- Each pin has an unique number associated with it in regs-gpio.h, - eg S3C2410_GPA0 or S3C2410_GPF1. These defines are used to tell + e.g. S3C2410_GPA(0) or S3C2410_GPF(1). These defines are used to tell the GPIO functions which pin is to be used. + With the conversion to gpiolib, there is no longer a direct conversion + from gpio pin number to register base address as in earlier kernels. This + is due to the number space required for newer SoCs where the later + GPIOs are not contiguous. + Configuring a pin ----------------- @@ -46,26 +109,27 @@ Configuring a pin The following function allows the configuration of a given pin to be changed. - void s3c2410_gpio_cfgpin(unsigned int pin, unsigned int function); + void s3c_gpio_cfgpin(unsigned int pin, unsigned int function); - Eg: + e.g.: - s3c2410_gpio_cfgpin(S3C2410_GPA0, S3C2410_GPA0_ADDR0); - s3c2410_gpio_cfgpin(S3C2410_GPE8, S3C2410_GPE8_SDDAT1); + s3c_gpio_cfgpin(S3C2410_GPA(0), S3C_GPIO_SFN(1)); + s3c_gpio_cfgpin(S3C2410_GPE(8), S3C_GPIO_SFN(2)); - which would turn GPA0 into the lowest Address line A0, and set - GPE8 to be connected to the SDIO/MMC controller's SDDAT1 line. + which would turn GPA(0) into the lowest Address line A0, and set + GPE(8) to be connected to the SDIO/MMC controller's SDDAT1 line. Reading the current configuration --------------------------------- - The current configuration of a pin can be read by using: + The current configuration of a pin can be read by using standard + gpiolib function: - s3c2410_gpio_getcfg(unsigned int pin); + s3c_gpio_getcfg(unsigned int pin); The return value will be from the same set of values which can be - passed to s3c2410_gpio_cfgpin(). + passed to s3c_gpio_cfgpin(). Configuring a pull-up resistor @@ -75,48 +139,33 @@ Configuring a pull-up resistor pull-up resistors enabled. This can be configured by the following function: - void s3c2410_gpio_pullup(unsigned int pin, unsigned int to); - - Where the to value is zero to set the pull-up off, and 1 to enable - the specified pull-up. Any other values are currently undefined. + void s3c_gpio_setpull(unsigned int pin, unsigned int to); + Where the to value is S3C_GPIO_PULL_NONE to set the pull-up off, + and S3C_GPIO_PULL_UP to enable the specified pull-up. Any other + values are currently undefined. -Getting the state of a PIN --------------------------- - The state of a pin can be read by using the function: +Getting and setting the state of a PIN +-------------------------------------- - unsigned int s3c2410_gpio_getpin(unsigned int pin); - - This will return either zero or non-zero. Do not count on this - function returning 1 if the pin is set. - - -Setting the state of a PIN --------------------------- - - The value an pin is outputing can be modified by using the following: - - void s3c2410_gpio_setpin(unsigned int pin, unsigned int to); - - Which sets the given pin to the value. Use 0 to write 0, and 1 to - set the output to 1. + These calls are now implemented by the relevant gpiolib calls, convert + your board or driver to use gpiolib. Getting the IRQ number associated with a PIN -------------------------------------------- - The following function can map the given pin number to an IRQ + A standard gpiolib function can map the given pin number to an IRQ number to pass to the IRQ system. - int s3c2410_gpio_getirq(unsigned int pin); + int gpio_to_irq(unsigned int pin); Note, not all pins have an IRQ. -Authour +Author ------- - Ben Dooks, 03 October 2004 -(c) 2004 Ben Dooks, Simtec Electronics +Copyright 2004 Ben Dooks, Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/H1940.txt b/Documentation/arm/Samsung-S3C24XX/H1940.txt index d6b1de92b11..b738859b1fc 100644 --- a/Documentation/arm/Samsung-S3C24XX/H1940.txt +++ b/Documentation/arm/Samsung-S3C24XX/H1940.txt @@ -23,7 +23,7 @@ Support http://handhelds.org/moin/moin.cgi/HpIpaqH1940 - Herbert Pötzl pages: + Herbert Pötzl pages: http://vserver.13thfloor.at/H1940/ @@ -32,9 +32,9 @@ Maintainers ----------- This project is being maintained and developed by a variety - of people, including Ben Dooks, Arnaud Patard, and Herbert Pötzl. + of people, including Ben Dooks, Arnaud Patard, and Herbert Pötzl. Thanks to the many others who have also provided support. -(c) 2005 Ben Dooks
\ No newline at end of file +(c) 2005 Ben Dooks diff --git a/Documentation/arm/Samsung-S3C24XX/NAND.txt b/Documentation/arm/Samsung-S3C24XX/NAND.txt new file mode 100644 index 00000000000..bc478a3409b --- /dev/null +++ b/Documentation/arm/Samsung-S3C24XX/NAND.txt @@ -0,0 +1,30 @@ + S3C24XX NAND Support + ==================== + +Introduction +------------ + +Small Page NAND +--------------- + +The driver uses a 512 byte (1 page) ECC code for this setup. The +ECC code is not directly compatible with the default kernel ECC +code, so the driver enforces its own OOB layout and ECC parameters + +Large Page NAND +--------------- + +The driver is capable of handling NAND flash with a 2KiB page +size, with support for hardware ECC generation and correction. + +Unlike the 512byte page mode, the driver generates ECC data for +each 256 byte block in an 2KiB page. This means that more than +one error in a page can be rectified. It also means that the +OOB layout remains the default kernel layout for these flashes. + + +Document Author +--------------- + +Ben Dooks, Copyright 2007 Simtec Electronics + diff --git a/Documentation/arm/Samsung-S3C24XX/Overview.txt b/Documentation/arm/Samsung-S3C24XX/Overview.txt index 3e46d2a3115..359587b2367 100644 --- a/Documentation/arm/Samsung-S3C24XX/Overview.txt +++ b/Documentation/arm/Samsung-S3C24XX/Overview.txt @@ -8,11 +8,18 @@ Introduction The Samsung S3C24XX range of ARM9 System-on-Chip CPUs are supported by the 's3c2410' architecture of ARM Linux. Currently the S3C2410, - S3C2440 and S3C2442 devices are supported. + S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443 and S3C2450 devices + are supported. - Support for the S3C2400 series is in progress. + Support for the S3C2400 and S3C24A0 series was never completed and the + corresponding code has been removed after a while. If someone wishes to + revive this effort, partial support can be retrieved from earlier Linux + versions. - Support for the S3C2412 and S3C2413 CPUs is being merged. + The S3C2416 and S3C2450 devices are very similar and S3C2450 support is + included under the arch/arm/mach-s3c2416 directory. Note, whilst core + support for these SoCs is in, work on some of the extra peripherals + and extra interrupts is still ongoing. Configuration @@ -26,6 +33,38 @@ Configuration please check the machine specific documentation. +Layout +------ + + The core support files are located in the platform code contained in + arch/arm/plat-s3c24xx with headers in include/asm-arm/plat-s3c24xx. + This directory should be kept to items shared between the platform + code (arch/arm/plat-s3c24xx) and the arch/arm/mach-s3c24* code. + + Each cpu has a directory with the support files for it, and the + machines that carry the device. For example S3C2410 is contained + in arch/arm/mach-s3c2410 and S3C2440 in arch/arm/mach-s3c2440 + + Register, kernel and platform data definitions are held in the + arch/arm/mach-s3c2410 directory./include/mach + +arch/arm/plat-s3c24xx: + + Files in here are either common to all the s3c24xx family, + or are common to only some of them with names to indicate this + status. The files that are not common to all are generally named + with the initial cpu they support in the series to ensure a short + name without any possibility of confusion with newer devices. + + As an example, initially s3c244x would cover s3c2440 and s3c2442, but + with the s3c2443 which does not share many of the same drivers in + this directory, the name becomes invalid. We stick to s3c2440-<x> + to indicate a driver that is s3c2440 and s3c2442 compatible. + + This does mean that to find the status of any given SoC, a number + of directories may need to be searched. + + Machines -------- @@ -76,11 +115,20 @@ Machines A S3C2410 based PDA from Acer. There is a Wiki page at http://handhelds.org/moin/moin.cgi/AcerN30Documentation . + AML M5900 + + American Microsystems' M5900 + + Nex Vision Nexcoder + Nex Vision Otom + + Two machines by Nex Vision + Adding New Machines ------------------- - The archicture has been designed to support as many machines as can + The architecture has been designed to support as many machines as can be configured for it in one kernel build, and any future additions should keep this in mind before altering items outside of their own machine files. @@ -115,6 +163,10 @@ RTC Support for the onboard RTC unit, including alarm function. + This has recently been upgraded to use the new RTC core, + and the module has been renamed to rtc-s3c to fit in with + the new rtc naming scheme. + Watchdog -------- @@ -128,7 +180,20 @@ NAND The current kernels now have support for the s3c2410 NAND controller. If there are any problems the latest linux-mtd - CVS can be found from http://www.linux-mtd.infradead.org/ + code can be found from http://www.linux-mtd.infradead.org/ + + For more information see Documentation/arm/Samsung-S3C24XX/NAND.txt + + +SD/MMC +------ + + The SD/MMC hardware pre S3C2443 is supported in the current + kernel, the driver is drivers/mmc/host/s3cmci.c and supports + 1 and 4 bit SD or MMC cards. + + The SDIO behaviour of this driver has not been fully tested. There is no + current support for hardware SDIO interrupts. Serial @@ -150,6 +215,16 @@ GPIO The core contains support for manipulating the GPIO, see the documentation in GPIO.txt in the same directory as this file. + Newer kernels carry GPIOLIB, and support is being moved towards + this with some of the older support in line to be removed. + + As of v2.6.34, the move towards using gpiolib support is almost + complete, and very little of the old calls are left. + + See Documentation/arm/Samsung-S3C24XX/GPIO.txt for the S3C24XX specific + support and Documentation/arm/Samsung/GPIO.txt for the core Samsung + implementation. + Clock Management ---------------- @@ -168,6 +243,21 @@ Suspend to RAM See Suspend.txt for more information. +SPI +--- + + SPI drivers are available for both the in-built hardware + (although there is no DMA support yet) and a generic + GPIO based solution. + + +LEDs +---- + + There is support for GPIO based LEDs via a platform driver + in the LED subsystem. + + Platform Data ------------- @@ -225,4 +315,4 @@ Port Contributors Document Author --------------- -Ben Dooks, (c) 2004-2005,2006 Simtec Electronics +Ben Dooks, Copyright 2004-2006 Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/S3C2412.txt b/Documentation/arm/Samsung-S3C24XX/S3C2412.txt index cb82a7fc790..f057876b920 100644 --- a/Documentation/arm/Samsung-S3C24XX/S3C2412.txt +++ b/Documentation/arm/Samsung-S3C24XX/S3C2412.txt @@ -80,7 +80,7 @@ RTC Watchdog -------- - The watchdog harware is the same as the S3C2410, and is supported by + The watchdog hardware is the same as the S3C2410, and is supported by the s3c2410_wdt driver. @@ -117,4 +117,4 @@ ATA Document Author --------------- -Ben Dooks, (c) 2006 Simtec Electronics +Ben Dooks, Copyright 2006 Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/S3C2413.txt b/Documentation/arm/Samsung-S3C24XX/S3C2413.txt index ab2a88858f1..909bdc7dd7b 100644 --- a/Documentation/arm/Samsung-S3C24XX/S3C2413.txt +++ b/Documentation/arm/Samsung-S3C24XX/S3C2413.txt @@ -18,4 +18,4 @@ Camera Interface Document Author --------------- -Ben Dooks, (c) 2006 Simtec Electronics +Ben Dooks, Copyright 2006 Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/SMDK2440.txt b/Documentation/arm/Samsung-S3C24XX/SMDK2440.txt index 32e1eae6a25..429390bd468 100644 --- a/Documentation/arm/Samsung-S3C24XX/SMDK2440.txt +++ b/Documentation/arm/Samsung-S3C24XX/SMDK2440.txt @@ -53,4 +53,4 @@ Maintainers and to Simtec Electronics for allowing me time to work on this. -(c) 2004 Ben Dooks
\ No newline at end of file +(c) 2004 Ben Dooks diff --git a/Documentation/arm/Samsung-S3C24XX/Suspend.txt b/Documentation/arm/Samsung-S3C24XX/Suspend.txt index e12bc3284a2..1ca63b3e563 100644 --- a/Documentation/arm/Samsung-S3C24XX/Suspend.txt +++ b/Documentation/arm/Samsung-S3C24XX/Suspend.txt @@ -5,10 +5,10 @@ Introduction ------------ - The S3C2410 supports a low-power suspend mode, where the SDRAM is kept + The S3C24XX supports a low-power suspend mode, where the SDRAM is kept in Self-Refresh mode, and all but the essential peripheral blocks are powered down. For more information on how this works, please look - at the S3C2410 datasheets from Samsung. + at the relevant CPU datasheet from Samsung. Requirements @@ -40,13 +40,13 @@ Resuming Machine Support --------------- - The machine specific functions must call the s3c2410_pm_init() function + The machine specific functions must call the s3c_pm_init() function to say that its bootloader is capable of resuming. This can be as simple as adding the following to the machine's definition: - INITMACHINE(s3c2410_pm_init) + INITMACHINE(s3c_pm_init) - A board can do its own setup before calling s3c2410_pm_init, if it + A board can do its own setup before calling s3c_pm_init, if it needs to setup anything else for power management support. There is currently no support for over-riding the default method of @@ -56,6 +56,27 @@ Machine Support Note, the original method of adding an late_initcall() is wrong, and will end up initialising all compiled machines' pm init! + The following is an example of code used for testing wakeup from + an falling edge on IRQ_EINT0: + + +static irqreturn_t button_irq(int irq, void *pw) +{ + return IRQ_HANDLED; +} + +statuc void __init machine_init(void) +{ + ... + + request_irq(IRQ_EINT0, button_irq, IRQF_TRIGGER_FALLING, + "button-irq-eint0", NULL); + + enable_irq_wake(IRQ_EINT0); + + s3c_pm_init(); +} + Debugging --------- @@ -70,6 +91,12 @@ Debugging care should be taken that any external clock sources that the UARTs rely on are still enabled at that point. + 3) If any debugging is placed in the resume path, then it must have the + relevant clocks and peripherals setup before use (ie, bootloader). + + For example, if you transmit a character from the UART, the baud + rate and uart controls must be setup beforehand. + Configuration ------------- @@ -89,6 +116,10 @@ Configuration Allows the entire memory to be checksummed before and after the suspend to see if there has been any corruption of the contents. + Note, the time to calculate the CRC is dependent on the CPU speed + and the size of memory. For an 64Mbyte RAM area on an 200MHz + S3C2410, this can take approximately 4 seconds to complete. + This support requires the CRC32 function to be enabled. @@ -102,5 +133,5 @@ Configuration Document Author --------------- -Ben Dooks, (c) 2004 Simtec Electronics +Ben Dooks, Copyright 2004 Simtec Electronics diff --git a/Documentation/arm/Samsung-S3C24XX/USB-Host.txt b/Documentation/arm/Samsung-S3C24XX/USB-Host.txt index b93b68e2b14..f82b1faefad 100644 --- a/Documentation/arm/Samsung-S3C24XX/USB-Host.txt +++ b/Documentation/arm/Samsung-S3C24XX/USB-Host.txt @@ -49,7 +49,7 @@ Board Support Platform Data ------------- - See linux/include/asm-arm/arch-s3c2410/usb-control.h for the + See arch/arm/mach-s3c2410/include/mach/usb-control.h for the descriptions of the platform device data. An implementation can be found in linux/arch/arm/mach-s3c2410/usb-simtec.c . @@ -90,4 +90,4 @@ Platform Data Document Author --------------- -Ben Dooks, (c) 2005 Simtec Electronics +Ben Dooks, Copyright 2005 Simtec Electronics diff --git a/Documentation/arm/Samsung/GPIO.txt b/Documentation/arm/Samsung/GPIO.txt new file mode 100644 index 00000000000..795adfd8808 --- /dev/null +++ b/Documentation/arm/Samsung/GPIO.txt @@ -0,0 +1,40 @@ + Samsung GPIO implementation + =========================== + +Introduction +------------ + +This outlines the Samsung GPIO implementation and the architecture +specific calls provided alongside the drivers/gpio core. + + +S3C24XX (Legacy) +---------------- + +See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information +about these devices. Their implementation has been brought into line +with the core samsung implementation described in this document. + + +GPIOLIB integration +------------------- + +The gpio implementation uses gpiolib as much as possible, only providing +specific calls for the items that require Samsung specific handling, such +as pin special-function or pull resistor control. + +GPIO numbering is synchronised between the Samsung and gpiolib system. + + +PIN configuration +----------------- + +Pin configuration is specific to the Samsung architecture, with each SoC +registering the necessary information for the core gpio configuration +implementation to configure pins as necessary. + +The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a +driver or machine to change gpio configuration. + +See arch/arm/plat-samsung/include/plat/gpio-cfg.h for more information +on these functions. diff --git a/Documentation/arm/Samsung/Overview.txt b/Documentation/arm/Samsung/Overview.txt new file mode 100644 index 00000000000..658abb258ce --- /dev/null +++ b/Documentation/arm/Samsung/Overview.txt @@ -0,0 +1,97 @@ + Samsung ARM Linux Overview + ========================== + +Introduction +------------ + + The Samsung range of ARM SoCs spans many similar devices, from the initial + ARM9 through to the newest ARM cores. This document shows an overview of + the current kernel support, how to use it and where to find the code + that supports this. + + The currently supported SoCs are: + + - S3C24XX: See Documentation/arm/Samsung-S3C24XX/Overview.txt for full list + - S3C64XX: S3C6400 and S3C6410 + - S5P6440 + - S5PC100 + - S5PC110 / S5PV210 + + +S3C24XX Systems +--------------- + + There is still documentation in Documnetation/arm/Samsung-S3C24XX/ which + deals with the architecture and drivers specific to these devices. + + See Documentation/arm/Samsung-S3C24XX/Overview.txt for more information + on the implementation details and specific support. + + +Configuration +------------- + + A number of configurations are supplied, as there is no current way of + unifying all the SoCs into one kernel. + + s5p6440_defconfig - S5P6440 specific default configuration + s5pc100_defconfig - S5PC100 specific default configuration + s5pc110_defconfig - S5PC110 specific default configuration + s5pv210_defconfig - S5PV210 specific default configuration + + +Layout +------ + + The directory layout is currently being restructured, and consists of + several platform directories and then the machine specific directories + of the CPUs being built for. + + plat-samsung provides the base for all the implementations, and is the + last in the line of include directories that are processed for the build + specific information. It contains the base clock, GPIO and device definitions + to get the system running. + + plat-s3c24xx is for s3c24xx specific builds, see the S3C24XX docs. + + plat-s5p is for s5p specific builds, and contains common support for the + S5P specific systems. Not all S5Ps use all the features in this directory + due to differences in the hardware. + + +Layout changes +-------------- + + The old plat-s3c and plat-s5pc1xx directories have been removed, with + support moved to either plat-samsung or plat-s5p as necessary. These moves + where to simplify the include and dependency issues involved with having + so many different platform directories. + + It was decided to remove plat-s5pc1xx as some of the support was already + in plat-s5p or plat-samsung, with the S5PC110 support added with S5PV210 + the only user was the S5PC100. The S5PC100 specific items where moved to + arch/arm/mach-s5pc100. + + + + +Port Contributors +----------------- + + Ben Dooks (BJD) + Vincent Sanders + Herbert Potzl + Arnaud Patard (RTP) + Roc Wu + Klaus Fetscher + Dimitry Andric + Shannon Holland + Guillaume Gourat (NexVision) + Christer Weinigel (wingel) (Acer N30) + Lucas Correia Villa Real (S3C2400 port) + + +Document Author +--------------- + +Copyright 2009-2010 Ben Dooks <ben-linux@fluff.org> diff --git a/Documentation/arm/Samsung/clksrc-change-registers.awk b/Documentation/arm/Samsung/clksrc-change-registers.awk new file mode 100755 index 00000000000..0c50220851f --- /dev/null +++ b/Documentation/arm/Samsung/clksrc-change-registers.awk @@ -0,0 +1,167 @@ +#!/usr/bin/awk -f +# +# Copyright 2010 Ben Dooks <ben-linux@fluff.org> +# +# Released under GPLv2 + +# example usage +# ./clksrc-change-registers.awk arch/arm/plat-s5pc1xx/include/plat/regs-clock.h < src > dst + +function extract_value(s) +{ + eqat = index(s, "=") + comat = index(s, ",") + return substr(s, eqat+2, (comat-eqat)-2) +} + +function remove_brackets(b) +{ + return substr(b, 2, length(b)-2) +} + +function splitdefine(l, p) +{ + r = split(l, tp) + + p[0] = tp[2] + p[1] = remove_brackets(tp[3]) +} + +function find_length(f) +{ + if (0) + printf "find_length " f "\n" > "/dev/stderr" + + if (f ~ /0x1/) + return 1 + else if (f ~ /0x3/) + return 2 + else if (f ~ /0x7/) + return 3 + else if (f ~ /0xf/) + return 4 + + printf "unknown legnth " f "\n" > "/dev/stderr" + exit +} + +function find_shift(s) +{ + id = index(s, "<") + if (id <= 0) { + printf "cannot find shift " s "\n" > "/dev/stderr" + exit + } + + return substr(s, id+2) +} + + +BEGIN { + if (ARGC < 2) { + print "too few arguments" > "/dev/stderr" + exit + } + +# read the header file and find the mask values that we will need +# to replace and create an associative array of values + + while (getline line < ARGV[1] > 0) { + if (line ~ /\#define.*_MASK/ && + !(line ~ /S5PC100_EPLL_MASK/) && + !(line ~ /USB_SIG_MASK/)) { + splitdefine(line, fields) + name = fields[0] + if (0) + printf "MASK " line "\n" > "/dev/stderr" + dmask[name,0] = find_length(fields[1]) + dmask[name,1] = find_shift(fields[1]) + if (0) + printf "=> '" name "' LENGTH=" dmask[name,0] " SHIFT=" dmask[name,1] "\n" > "/dev/stderr" + } else { + } + } + + delete ARGV[1] +} + +/clksrc_clk.*=.*{/ { + shift="" + mask="" + divshift="" + reg_div="" + reg_src="" + indent=1 + + print $0 + + for(; indent >= 1;) { + if ((getline line) <= 0) { + printf "unexpected end of file" > "/dev/stderr" + exit 1; + } + + if (line ~ /\.shift/) { + shift = extract_value(line) + } else if (line ~ /\.mask/) { + mask = extract_value(line) + } else if (line ~ /\.reg_divider/) { + reg_div = extract_value(line) + } else if (line ~ /\.reg_source/) { + reg_src = extract_value(line) + } else if (line ~ /\.divider_shift/) { + divshift = extract_value(line) + } else if (line ~ /{/) { + indent++ + print line + } else if (line ~ /}/) { + indent-- + + if (indent == 0) { + if (0) { + printf "shift '" shift "' ='" dmask[shift,0] "'\n" > "/dev/stderr" + printf "mask '" mask "'\n" > "/dev/stderr" + printf "dshft '" divshift "'\n" > "/dev/stderr" + printf "rdiv '" reg_div "'\n" > "/dev/stderr" + printf "rsrc '" reg_src "'\n" > "/dev/stderr" + } + + generated = mask + sub(reg_src, reg_div, generated) + + if (0) { + printf "/* rsrc " reg_src " */\n" + printf "/* rdiv " reg_div " */\n" + printf "/* shift " shift " */\n" + printf "/* mask " mask " */\n" + printf "/* generated " generated " */\n" + } + + if (reg_div != "") { + printf "\t.reg_div = { " + printf ".reg = " reg_div ", " + printf ".shift = " dmask[generated,1] ", " + printf ".size = " dmask[generated,0] ", " + printf "},\n" + } + + printf "\t.reg_src = { " + printf ".reg = " reg_src ", " + printf ".shift = " dmask[mask,1] ", " + printf ".size = " dmask[mask,0] ", " + + printf "},\n" + + } + + print line + } else { + print line + } + + if (0) + printf indent ":" line "\n" > "/dev/stderr" + } +} + +// && ! /clksrc_clk.*=.*{/ { print $0 } diff --git a/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen b/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen deleted file mode 100644 index 1e6a23fdf2f..00000000000 --- a/Documentation/arm/Sharp-LH/ADC-LH7-Touchscreen +++ /dev/null @@ -1,61 +0,0 @@ -README on the ADC/Touchscreen Controller -======================================== - -The LH79524 and LH7A404 include a built-in Analog to Digital -controller (ADC) that is used to process input from a touchscreen. -The driver only implements a four-wire touch panel protocol. - -The touchscreen driver is maintenance free except for the pen-down or -touch threshold. Some resistive displays and board combinations may -require tuning of this threshold. The driver exposes some of it's -internal state in the sys filesystem. If the kernel is configured -with it, CONFIG_SYSFS, and sysfs is mounted at /sys, there will be a -directory - - /sys/devices/platform/adc-lh7.0 - -containing these files. - - -r--r--r-- 1 root root 4096 Jan 1 00:00 samples - -rw-r--r-- 1 root root 4096 Jan 1 00:00 threshold - -r--r--r-- 1 root root 4096 Jan 1 00:00 threshold_range - -The threshold is the current touch threshold. It defaults to 750 on -most targets. - - # cat threshold - 750 - -The threshold_range contains the range of valid values for the -threshold. Values outside of this range will be silently ignored. - - # cat threshold_range - 0 1023 - -To change the threshold, write a value to the threshold file. - - # echo 500 > threshold - # cat threshold - 500 - -The samples file contains the most recently sampled values from the -ADC. There are 12. Below are typical of the last sampled values when -the pen has been released. The first two and last two samples are for -detecting whether or not the pen is down. The third through sixth are -X coordinate samples. The seventh through tenth are Y coordinate -samples. - - # cat samples - 1023 1023 0 0 0 0 530 529 530 529 1023 1023 - -To determine a reasonable threshold, press on the touch panel with an -appropriate stylus and read the values from samples. - - # cat samples - 1023 676 92 103 101 102 855 919 922 922 1023 679 - -The first and eleventh samples are discarded. Thus, the important -values are the second and twelfth which are used to determine if the -pen is down. When both are below the threshold, the driver registers -that the pen is down. When either is above the threshold, it -registers then pen is up. diff --git a/Documentation/arm/Sharp-LH/CompactFlash b/Documentation/arm/Sharp-LH/CompactFlash deleted file mode 100644 index 8616d877df9..00000000000 --- a/Documentation/arm/Sharp-LH/CompactFlash +++ /dev/null @@ -1,32 +0,0 @@ -README on the Compact Flash for Card Engines -============================================ - -There are three challenges in supporting the CF interface of the Card -Engines. First, every IO operation must be followed with IO to -another memory region. Second, the slot is wired for one-to-one -address mapping *and* it is wired for 16 bit access only. Second, the -interrupt request line from the CF device isn't wired. - -The IOBARRIER issue is covered in README.IOBARRIER. This isn't an -onerous problem. Enough said here. - -The addressing issue is solved in the -arch/arm/mach-lh7a40x/ide-lpd7a40x.c file with some awkward -work-arounds. We implement a special SELECT_DRIVE routine that is -called before the IDE driver performs its own SELECT_DRIVE. Our code -recognizes that the SELECT register cannot be modified without also -writing a command. It send an IDLE_IMMEDIATE command on selecting a -drive. The function also prevents drive select to the slave drive -since there can be only one. The awkward part is that the IDE driver, -even though we have a select procedure, also attempts to change the -drive by writing directly the SELECT register. This attempt is -explicitly blocked by the OUTB function--not pretty, but effective. - -The lack of interrupts is a more serious problem. Even though the CF -card is fast when compared to a normal IDE device, we don't know that -the CF is really flash. A user could use one of the very small hard -drives being shipped with a CF interface. The IDE code includes a -check for interfaces that lack an IRQ. In these cases, submitting a -command to the IDE controller is followed by a call to poll for -completion. If the device isn't immediately ready, it schedules a -timer to poll again later. diff --git a/Documentation/arm/Sharp-LH/IOBarrier b/Documentation/arm/Sharp-LH/IOBarrier deleted file mode 100644 index c0d8853672d..00000000000 --- a/Documentation/arm/Sharp-LH/IOBarrier +++ /dev/null @@ -1,45 +0,0 @@ -README on the IOBARRIER for CardEngine IO -========================================= - -Due to an unfortunate oversight when the Card Engines were designed, -the signals that control access to some peripherals, most notably the -SMC91C9111 ethernet controller, are not properly handled. - -The symptom is that some back to back IO with the peripheral returns -unreliable data. With the SMC chip, you'll see errors about the bank -register being 'screwed'. - -The cause is that the AEN signal to the SMC chip does not transition -for every memory access. It is driven through the CPLD from the CS7 -line of the CPU's static memory controller which is optimized to -eliminate unnecessary transitions. Yet, the SMC requires a transition -for every write access. The Sharp website has more information about -the effect this power-conserving feature has on peripheral -interfacing. - -The solution is to follow every write access to the SMC chip with an -access to another memory region that will force the CPU to release the -chip select line. It is important to guarantee that this access -forces the CPU off-chip. We map a page of SDRAM as if it were an -uncacheable IO device and read from it after every SMC IO write -operation. - - SMC IO - BARRIER IO - -Only this sequence is important. It does not matter that there is no -BARRIER IO before the access to the SMC chip because the AEN latch -only needs occurs after the SMC IO write cycle. The routines that -implement this work-around make an additional concession which is to -disable interrupts during the IO sequence. Other hardware devices -(the LogicPD CPLD) have registers in the same the physical memory -region as the SMC chip. An interrupt might allow an access to one of -those registers while SMC IO is being performed. - -You might be tempted to think that we have to access another device -attached to the static memory controller, but the empirical evidence -indicates that this is not so. Mapping 0x00000000 (flash) and -0xc0000000 (SDRAM) appear to have the same effect. Using SDRAM seems -to be faster. Choosing to access an undecoded memory region is not -desirable as there is no way to know how that chip select will be used -in the future. diff --git a/Documentation/arm/Sharp-LH/KEV7A400 b/Documentation/arm/Sharp-LH/KEV7A400 deleted file mode 100644 index be32b14cd53..00000000000 --- a/Documentation/arm/Sharp-LH/KEV7A400 +++ /dev/null @@ -1,8 +0,0 @@ -README on Implementing Linux for Sharp's KEV7a400 -================================================= - -This product has been discontinued by Sharp. For the time being, the -partially implemented code remains in the kernel. At some point in -the future, either the code will be finished or it will be removed -completely. This depends primarily on how many of the development -boards are in the field. diff --git a/Documentation/arm/Sharp-LH/LCDPanels b/Documentation/arm/Sharp-LH/LCDPanels deleted file mode 100644 index fb1b21c2f2f..00000000000 --- a/Documentation/arm/Sharp-LH/LCDPanels +++ /dev/null @@ -1,59 +0,0 @@ -README on the LCD Panels -======================== - -Configuration options for several LCD panels, available from Logic PD, -are included in the kernel source. This README will help you -understand the configuration data and give you some guidance for -adding support for other panels if you wish. - - -lcd-panels.h ------------- - -There is no way, at present, to detect which panel is attached to the -system at runtime. Thus the kernel configuration is static. The file -arch/arm/mach-ld7a40x/lcd-panels.h (or similar) defines all of the -panel specific parameters. - -It should be possible for this data to be shared among several device -families. The current layout may be insufficiently general, but it is -amenable to improvement. - - -PIXEL_CLOCK ------------ - -The panel data sheets will give a range of acceptable pixel clocks. -The fundamental LCDCLK input frequency is divided down by a PCD -constant in field '.tim2'. It may happen that it is impossible to set -the pixel clock within this range. A clock which is too slow will -tend to flicker. For the highest quality image, set the clock as high -as possible. - - -MARGINS -------- - -These values may be difficult to glean from the panel data sheet. In -the case of the Sharp panels, the upper margin is explicitly called -out as a specific number of lines from the top of the frame. The -other values may not matter as much as the panels tend to -automatically center the image. - - -Sync Sense ----------- - -The sense of the hsync and vsync pulses may be called out in the data -sheet. On one panel, the sense of these pulses determine the height -of the visible region on the panel. Most of the Sharp panels use -negative sense sync pulses set by the TIM2_IHS and TIM2_IVS bits in -'.tim2'. - - -Pel Layout ----------- - -The Sharp color TFT panels are all configured for 16 bit direct color -modes. The amba-lcd driver sets the pel mode to 565 for 5 bits of -each red and blue and 6 bits of green. diff --git a/Documentation/arm/Sharp-LH/LPD7A400 b/Documentation/arm/Sharp-LH/LPD7A400 deleted file mode 100644 index 3275b453bfd..00000000000 --- a/Documentation/arm/Sharp-LH/LPD7A400 +++ /dev/null @@ -1,15 +0,0 @@ -README on Implementing Linux for the Logic PD LPD7A400-10 -========================================================= - -- CPLD memory mapping - - The board designers chose to use high address lines for controlling - access to the CPLD registers. It turns out to be a big waste - because we're using an MMU and must map IO space into virtual - memory. The result is that we have to make a mapping for every - register. - -- Serial Console - - It may be OK not to use the serial console option if the user passes - the console device name to the kernel. This deserves some exploration. diff --git a/Documentation/arm/Sharp-LH/LPD7A40X b/Documentation/arm/Sharp-LH/LPD7A40X deleted file mode 100644 index 8c29a27e208..00000000000 --- a/Documentation/arm/Sharp-LH/LPD7A40X +++ /dev/null @@ -1,16 +0,0 @@ -README on Implementing Linux for the Logic PD LPD7A40X-10 -========================================================= - -- CPLD memory mapping - - The board designers chose to use high address lines for controlling - access to the CPLD registers. It turns out to be a big waste - because we're using an MMU and must map IO space into virtual - memory. The result is that we have to make a mapping for every - register. - -- Serial Console - - It may be OK not to use the serial console option if the user passes - the console device name to the kernel. This deserves some exploration. - diff --git a/Documentation/arm/Sharp-LH/SDRAM b/Documentation/arm/Sharp-LH/SDRAM deleted file mode 100644 index 93ddc23c2fa..00000000000 --- a/Documentation/arm/Sharp-LH/SDRAM +++ /dev/null @@ -1,51 +0,0 @@ -README on the SDRAM Controller for the LH7a40X -============================================== - -The standard configuration for the SDRAM controller generates a sparse -memory array. The precise layout is determined by the SDRAM chips. A -default kernel configuration assembles the discontiguous memory -regions into separate memory nodes via the NUMA (Non-Uniform Memory -Architecture) facilities. In this default configuration, the kernel -is forgiving about the precise layout. As long as it is given an -accurate picture of available memory by the bootloader the kernel will -execute correctly. - -The SDRC supports a mode where some of the chip select lines are -swapped in order to make SDRAM look like a synchronous ROM. Setting -this bit means that the RAM will present as a contiguous array. Some -programmers prefer this to the discontiguous layout. Be aware that -may be a penalty for this feature where some some configurations of -memory are significantly reduced; i.e. 64MiB of RAM appears as only 32 -MiB. - -There are a couple of configuration options to override the default -behavior. When the SROMLL bit is set and memory appears as a -contiguous array, there is no reason to support NUMA. -CONFIG_LH7A40X_CONTIGMEM disables NUMA support. When physical memory -is discontiguous, the memory tables are organized such that there are -two banks per nodes with a small gap between them. This layout wastes -some kernel memory for page tables representing non-existent memory. -CONFIG_LH7A40X_ONE_BANK_PER_NODE optimizes the node tables such that -there are no gaps. These options control the low level organization -of the memory management tables in ways that may prevent the kernel -from booting or may cause the kernel to allocated excessively large -page tables. Be warned. Only change these options if you know what -you are doing. The default behavior is a reasonable compromise that -will suit all users. - --- - -A typical 32MiB system with the default configuration options will -find physical memory managed as follows. - - node 0: 0xc0000000 4MiB - 0xc1000000 4MiB - node 1: 0xc4000000 4MiB - 0xc5000000 4MiB - node 2: 0xc8000000 4MiB - 0xc9000000 4MiB - node 3: 0xcc000000 4MiB - 0xcd000000 4MiB - -Setting CONFIG_LH7A40X_ONE_BANK_PER_NODE will put each bank into a -separate node. diff --git a/Documentation/arm/Sharp-LH/VectoredInterruptController b/Documentation/arm/Sharp-LH/VectoredInterruptController deleted file mode 100644 index 23047e9861e..00000000000 --- a/Documentation/arm/Sharp-LH/VectoredInterruptController +++ /dev/null @@ -1,80 +0,0 @@ -README on the Vectored Interrupt Controller of the LH7A404 -========================================================== - -The 404 revision of the LH7A40X series comes with two vectored -interrupts controllers. While the kernel does use some of the -features of these devices, it is far from the purpose for which they -were designed. - -When this README was written, the implementation of the VICs was in -flux. It is possible that some details, especially with priorities, -will change. - -The VIC support code is inspired by routines written by Sharp. - - -Priority Control ----------------- - -The significant reason for using the VIC's vectoring is to control -interrupt priorities. There are two tables in -arch/arm/mach-lh7a40x/irq-lh7a404.c that look something like this. - - static unsigned char irq_pri_vic1[] = { IRQ_GPIO3INTR, }; - static unsigned char irq_pri_vic2[] = { - IRQ_T3UI, IRQ_GPIO7INTR, - IRQ_UART1INTR, IRQ_UART2INTR, IRQ_UART3INTR, }; - -The initialization code reads these tables and inserts a vector -address and enable for each indicated IRQ. Vectored interrupts have -higher priority than non-vectored interrupts. So, on VIC1, -IRQ_GPIO3INTR will be served before any other non-FIQ interrupt. Due -to the way that the vectoring works, IRQ_T3UI is the next highest -priority followed by the other vectored interrupts on VIC2. After -that, the non-vectored interrupts are scanned in VIC1 then in VIC2. - - -ISR ---- - -The interrupt service routine macro get_irqnr() in -arch/arm/kernel/entry-armv.S scans the VICs for the next active -interrupt. The vectoring makes this code somewhat larger than it was -before using vectoring (refer to the LH7A400 implementation). In the -case where an interrupt is vectored, the implementation will tend to -be faster than the non-vectored version. However, the worst-case path -is longer. - -It is worth noting that at present, there is no need to read -VIC2_VECTADDR because the register appears to be shared between the -controllers. The code is written such that if this changes, it ought -to still work properly. - - -Vector Addresses ----------------- - -The proper use of the vectoring hardware would jump to the ISR -specified by the vectoring address. Linux isn't structured to take -advantage of this feature, though it might be possible to change -things to support it. - -In this implementation, the vectoring address is used to speed the -search for the active IRQ. The address is coded such that the lowest -6 bits store the IRQ number for vectored interrupts. These numbers -correspond to the bits in the interrupt status registers. IRQ zero is -the lowest interrupt bit in VIC1. IRQ 32 is the lowest interrupt bit -in VIC2. Because zero is a valid IRQ number and because we cannot -detect whether or not there is a valid vectoring address if that -address is zero, the eigth bit (0x100) is set for vectored interrupts. -The address for IRQ 0x18 (VIC2) is 0x118. Only the ninth bit is set -for the default handler on VIC1 and only the tenth bit is set for the -default handler on VIC2. - -In other words. - - 0x000 - no active interrupt - 0x1ii - vectored interrupt 0xii - 0x2xx - unvectored interrupt on VIC1 (xx is don't care) - 0x4xx - unvectored interrupt on VIC2 (xx is don't care) - diff --git a/Documentation/arm/cluster-pm-race-avoidance.txt b/Documentation/arm/cluster-pm-race-avoidance.txt new file mode 100644 index 00000000000..750b6fc24af --- /dev/null +++ b/Documentation/arm/cluster-pm-race-avoidance.txt @@ -0,0 +1,498 @@ +Cluster-wide Power-up/power-down race avoidance algorithm +========================================================= + +This file documents the algorithm which is used to coordinate CPU and +cluster setup and teardown operations and to manage hardware coherency +controls safely. + +The section "Rationale" explains what the algorithm is for and why it is +needed. "Basic model" explains general concepts using a simplified view +of the system. The other sections explain the actual details of the +algorithm in use. + + +Rationale +--------- + +In a system containing multiple CPUs, it is desirable to have the +ability to turn off individual CPUs when the system is idle, reducing +power consumption and thermal dissipation. + +In a system containing multiple clusters of CPUs, it is also desirable +to have the ability to turn off entire clusters. + +Turning entire clusters off and on is a risky business, because it +involves performing potentially destructive operations affecting a group +of independently running CPUs, while the OS continues to run. This +means that we need some coordination in order to ensure that critical +cluster-level operations are only performed when it is truly safe to do +so. + +Simple locking may not be sufficient to solve this problem, because +mechanisms like Linux spinlocks may rely on coherency mechanisms which +are not immediately enabled when a cluster powers up. Since enabling or +disabling those mechanisms may itself be a non-atomic operation (such as +writing some hardware registers and invalidating large caches), other +methods of coordination are required in order to guarantee safe +power-down and power-up at the cluster level. + +The mechanism presented in this document describes a coherent memory +based protocol for performing the needed coordination. It aims to be as +lightweight as possible, while providing the required safety properties. + + +Basic model +----------- + +Each cluster and CPU is assigned a state, as follows: + + DOWN + COMING_UP + UP + GOING_DOWN + + +---------> UP ----------+ + | v + + COMING_UP GOING_DOWN + + ^ | + +--------- DOWN <--------+ + + +DOWN: The CPU or cluster is not coherent, and is either powered off or + suspended, or is ready to be powered off or suspended. + +COMING_UP: The CPU or cluster has committed to moving to the UP state. + It may be part way through the process of initialisation and + enabling coherency. + +UP: The CPU or cluster is active and coherent at the hardware + level. A CPU in this state is not necessarily being used + actively by the kernel. + +GOING_DOWN: The CPU or cluster has committed to moving to the DOWN + state. It may be part way through the process of teardown and + coherency exit. + + +Each CPU has one of these states assigned to it at any point in time. +The CPU states are described in the "CPU state" section, below. + +Each cluster is also assigned a state, but it is necessary to split the +state value into two parts (the "cluster" state and "inbound" state) and +to introduce additional states in order to avoid races between different +CPUs in the cluster simultaneously modifying the state. The cluster- +level states are described in the "Cluster state" section. + +To help distinguish the CPU states from cluster states in this +discussion, the state names are given a CPU_ prefix for the CPU states, +and a CLUSTER_ or INBOUND_ prefix for the cluster states. + + +CPU state +--------- + +In this algorithm, each individual core in a multi-core processor is +referred to as a "CPU". CPUs are assumed to be single-threaded: +therefore, a CPU can only be doing one thing at a single point in time. + +This means that CPUs fit the basic model closely. + +The algorithm defines the following states for each CPU in the system: + + CPU_DOWN + CPU_COMING_UP + CPU_UP + CPU_GOING_DOWN + + cluster setup and + CPU setup complete policy decision + +-----------> CPU_UP ------------+ + | v + + CPU_COMING_UP CPU_GOING_DOWN + + ^ | + +----------- CPU_DOWN <----------+ + policy decision CPU teardown complete + or hardware event + + +The definitions of the four states correspond closely to the states of +the basic model. + +Transitions between states occur as follows. + +A trigger event (spontaneous) means that the CPU can transition to the +next state as a result of making local progress only, with no +requirement for any external event to happen. + + +CPU_DOWN: + + A CPU reaches the CPU_DOWN state when it is ready for + power-down. On reaching this state, the CPU will typically + power itself down or suspend itself, via a WFI instruction or a + firmware call. + + Next state: CPU_COMING_UP + Conditions: none + + Trigger events: + + a) an explicit hardware power-up operation, resulting + from a policy decision on another CPU; + + b) a hardware event, such as an interrupt. + + +CPU_COMING_UP: + + A CPU cannot start participating in hardware coherency until the + cluster is set up and coherent. If the cluster is not ready, + then the CPU will wait in the CPU_COMING_UP state until the + cluster has been set up. + + Next state: CPU_UP + Conditions: The CPU's parent cluster must be in CLUSTER_UP. + Trigger events: Transition of the parent cluster to CLUSTER_UP. + + Refer to the "Cluster state" section for a description of the + CLUSTER_UP state. + + +CPU_UP: + When a CPU reaches the CPU_UP state, it is safe for the CPU to + start participating in local coherency. + + This is done by jumping to the kernel's CPU resume code. + + Note that the definition of this state is slightly different + from the basic model definition: CPU_UP does not mean that the + CPU is coherent yet, but it does mean that it is safe to resume + the kernel. The kernel handles the rest of the resume + procedure, so the remaining steps are not visible as part of the + race avoidance algorithm. + + The CPU remains in this state until an explicit policy decision + is made to shut down or suspend the CPU. + + Next state: CPU_GOING_DOWN + Conditions: none + Trigger events: explicit policy decision + + +CPU_GOING_DOWN: + + While in this state, the CPU exits coherency, including any + operations required to achieve this (such as cleaning data + caches). + + Next state: CPU_DOWN + Conditions: local CPU teardown complete + Trigger events: (spontaneous) + + +Cluster state +------------- + +A cluster is a group of connected CPUs with some common resources. +Because a cluster contains multiple CPUs, it can be doing multiple +things at the same time. This has some implications. In particular, a +CPU can start up while another CPU is tearing the cluster down. + +In this discussion, the "outbound side" is the view of the cluster state +as seen by a CPU tearing the cluster down. The "inbound side" is the +view of the cluster state as seen by a CPU setting the CPU up. + +In order to enable safe coordination in such situations, it is important +that a CPU which is setting up the cluster can advertise its state +independently of the CPU which is tearing down the cluster. For this +reason, the cluster state is split into two parts: + + "cluster" state: The global state of the cluster; or the state + on the outbound side: + + CLUSTER_DOWN + CLUSTER_UP + CLUSTER_GOING_DOWN + + "inbound" state: The state of the cluster on the inbound side. + + INBOUND_NOT_COMING_UP + INBOUND_COMING_UP + + + The different pairings of these states results in six possible + states for the cluster as a whole: + + CLUSTER_UP + +==========> INBOUND_NOT_COMING_UP -------------+ + # | + | + CLUSTER_UP <----+ | + INBOUND_COMING_UP | v + + ^ CLUSTER_GOING_DOWN CLUSTER_GOING_DOWN + # INBOUND_COMING_UP <=== INBOUND_NOT_COMING_UP + + CLUSTER_DOWN | | + INBOUND_COMING_UP <----+ | + | + ^ | + +=========== CLUSTER_DOWN <------------+ + INBOUND_NOT_COMING_UP + + Transitions -----> can only be made by the outbound CPU, and + only involve changes to the "cluster" state. + + Transitions ===##> can only be made by the inbound CPU, and only + involve changes to the "inbound" state, except where there is no + further transition possible on the outbound side (i.e., the + outbound CPU has put the cluster into the CLUSTER_DOWN state). + + The race avoidance algorithm does not provide a way to determine + which exact CPUs within the cluster play these roles. This must + be decided in advance by some other means. Refer to the section + "Last man and first man selection" for more explanation. + + + CLUSTER_DOWN/INBOUND_NOT_COMING_UP is the only state where the + cluster can actually be powered down. + + The parallelism of the inbound and outbound CPUs is observed by + the existence of two different paths from CLUSTER_GOING_DOWN/ + INBOUND_NOT_COMING_UP (corresponding to GOING_DOWN in the basic + model) to CLUSTER_DOWN/INBOUND_COMING_UP (corresponding to + COMING_UP in the basic model). The second path avoids cluster + teardown completely. + + CLUSTER_UP/INBOUND_COMING_UP is equivalent to UP in the basic + model. The final transition to CLUSTER_UP/INBOUND_NOT_COMING_UP + is trivial and merely resets the state machine ready for the + next cycle. + + Details of the allowable transitions follow. + + The next state in each case is notated + + <cluster state>/<inbound state> (<transitioner>) + + where the <transitioner> is the side on which the transition + can occur; either the inbound or the outbound side. + + +CLUSTER_DOWN/INBOUND_NOT_COMING_UP: + + Next state: CLUSTER_DOWN/INBOUND_COMING_UP (inbound) + Conditions: none + Trigger events: + + a) an explicit hardware power-up operation, resulting + from a policy decision on another CPU; + + b) a hardware event, such as an interrupt. + + +CLUSTER_DOWN/INBOUND_COMING_UP: + + In this state, an inbound CPU sets up the cluster, including + enabling of hardware coherency at the cluster level and any + other operations (such as cache invalidation) which are required + in order to achieve this. + + The purpose of this state is to do sufficient cluster-level + setup to enable other CPUs in the cluster to enter coherency + safely. + + Next state: CLUSTER_UP/INBOUND_COMING_UP (inbound) + Conditions: cluster-level setup and hardware coherency complete + Trigger events: (spontaneous) + + +CLUSTER_UP/INBOUND_COMING_UP: + + Cluster-level setup is complete and hardware coherency is + enabled for the cluster. Other CPUs in the cluster can safely + enter coherency. + + This is a transient state, leading immediately to + CLUSTER_UP/INBOUND_NOT_COMING_UP. All other CPUs on the cluster + should consider treat these two states as equivalent. + + Next state: CLUSTER_UP/INBOUND_NOT_COMING_UP (inbound) + Conditions: none + Trigger events: (spontaneous) + + +CLUSTER_UP/INBOUND_NOT_COMING_UP: + + Cluster-level setup is complete and hardware coherency is + enabled for the cluster. Other CPUs in the cluster can safely + enter coherency. + + The cluster will remain in this state until a policy decision is + made to power the cluster down. + + Next state: CLUSTER_GOING_DOWN/INBOUND_NOT_COMING_UP (outbound) + Conditions: none + Trigger events: policy decision to power down the cluster + + +CLUSTER_GOING_DOWN/INBOUND_NOT_COMING_UP: + + An outbound CPU is tearing the cluster down. The selected CPU + must wait in this state until all CPUs in the cluster are in the + CPU_DOWN state. + + When all CPUs are in the CPU_DOWN state, the cluster can be torn + down, for example by cleaning data caches and exiting + cluster-level coherency. + + To avoid wasteful unnecessary teardown operations, the outbound + should check the inbound cluster state for asynchronous + transitions to INBOUND_COMING_UP. Alternatively, individual + CPUs can be checked for entry into CPU_COMING_UP or CPU_UP. + + + Next states: + + CLUSTER_DOWN/INBOUND_NOT_COMING_UP (outbound) + Conditions: cluster torn down and ready to power off + Trigger events: (spontaneous) + + CLUSTER_GOING_DOWN/INBOUND_COMING_UP (inbound) + Conditions: none + Trigger events: + + a) an explicit hardware power-up operation, + resulting from a policy decision on another + CPU; + + b) a hardware event, such as an interrupt. + + +CLUSTER_GOING_DOWN/INBOUND_COMING_UP: + + The cluster is (or was) being torn down, but another CPU has + come online in the meantime and is trying to set up the cluster + again. + + If the outbound CPU observes this state, it has two choices: + + a) back out of teardown, restoring the cluster to the + CLUSTER_UP state; + + b) finish tearing the cluster down and put the cluster + in the CLUSTER_DOWN state; the inbound CPU will + set up the cluster again from there. + + Choice (a) permits the removal of some latency by avoiding + unnecessary teardown and setup operations in situations where + the cluster is not really going to be powered down. + + + Next states: + + CLUSTER_UP/INBOUND_COMING_UP (outbound) + Conditions: cluster-level setup and hardware + coherency complete + Trigger events: (spontaneous) + + CLUSTER_DOWN/INBOUND_COMING_UP (outbound) + Conditions: cluster torn down and ready to power off + Trigger events: (spontaneous) + + +Last man and First man selection +-------------------------------- + +The CPU which performs cluster tear-down operations on the outbound side +is commonly referred to as the "last man". + +The CPU which performs cluster setup on the inbound side is commonly +referred to as the "first man". + +The race avoidance algorithm documented above does not provide a +mechanism to choose which CPUs should play these roles. + + +Last man: + +When shutting down the cluster, all the CPUs involved are initially +executing Linux and hence coherent. Therefore, ordinary spinlocks can +be used to select a last man safely, before the CPUs become +non-coherent. + + +First man: + +Because CPUs may power up asynchronously in response to external wake-up +events, a dynamic mechanism is needed to make sure that only one CPU +attempts to play the first man role and do the cluster-level +initialisation: any other CPUs must wait for this to complete before +proceeding. + +Cluster-level initialisation may involve actions such as configuring +coherency controls in the bus fabric. + +The current implementation in mcpm_head.S uses a separate mutual exclusion +mechanism to do this arbitration. This mechanism is documented in +detail in vlocks.txt. + + +Features and Limitations +------------------------ + +Implementation: + + The current ARM-based implementation is split between + arch/arm/common/mcpm_head.S (low-level inbound CPU operations) and + arch/arm/common/mcpm_entry.c (everything else): + + __mcpm_cpu_going_down() signals the transition of a CPU to the + CPU_GOING_DOWN state. + + __mcpm_cpu_down() signals the transition of a CPU to the CPU_DOWN + state. + + A CPU transitions to CPU_COMING_UP and then to CPU_UP via the + low-level power-up code in mcpm_head.S. This could + involve CPU-specific setup code, but in the current + implementation it does not. + + __mcpm_outbound_enter_critical() and __mcpm_outbound_leave_critical() + handle transitions from CLUSTER_UP to CLUSTER_GOING_DOWN + and from there to CLUSTER_DOWN or back to CLUSTER_UP (in + the case of an aborted cluster power-down). + + These functions are more complex than the __mcpm_cpu_*() + functions due to the extra inter-CPU coordination which + is needed for safe transitions at the cluster level. + + A cluster transitions from CLUSTER_DOWN back to CLUSTER_UP via + the low-level power-up code in mcpm_head.S. This + typically involves platform-specific setup code, + provided by the platform-specific power_up_setup + function registered via mcpm_sync_init. + +Deep topologies: + + As currently described and implemented, the algorithm does not + support CPU topologies involving more than two levels (i.e., + clusters of clusters are not supported). The algorithm could be + extended by replicating the cluster-level states for the + additional topological levels, and modifying the transition + rules for the intermediate (non-outermost) cluster levels. + + +Colophon +-------- + +Originally created and documented by Dave Martin for Linaro Limited, in +collaboration with Nicolas Pitre and Achin Gupta. + +Copyright (C) 2012-2013 Linaro Limited +Distributed under the terms of Version 2 of the GNU General Public +License, as defined in linux/COPYING. diff --git a/Documentation/arm/empeg/README b/Documentation/arm/empeg/README deleted file mode 100644 index 09cc8d03ae5..00000000000 --- a/Documentation/arm/empeg/README +++ /dev/null @@ -1,13 +0,0 @@ -Empeg, Ltd's Empeg MP3 Car Audio Player - -The initial design is to go in your car, but you can use it at home, on a -boat... almost anywhere. The principle is to store CD-quality music using -MPEG technology onto a hard disk in the unit, and use the power of the -embedded computer to serve up the music you want. - -For more details, see: - - http://www.empeg.com - - - diff --git a/Documentation/arm/empeg/ir.txt b/Documentation/arm/empeg/ir.txt deleted file mode 100644 index 10a29745016..00000000000 --- a/Documentation/arm/empeg/ir.txt +++ /dev/null @@ -1,49 +0,0 @@ -Infra-red driver documentation. - -Mike Crowe <mac@empeg.com> -(C) Empeg Ltd 1999 - -Not a lot here yet :-) - -The Kenwood KCA-R6A remote control generates a sequence like the following: - -Go low for approx 16T (Around 9000us) -Go high for approx 8T (Around 4000us) -Go low for less than 2T (Around 750us) - -For each of the 32 bits - Go high for more than 2T (Around 1500us) == 1 - Go high for less than T (Around 400us) == 0 - Go low for less than 2T (Around 750us) - -Rather than repeat a signal when the button is held down certain buttons -generate the following code to indicate repetition. - -Go low for approx 16T -Go high for approx 4T -Go low for less than 2T - -(By removing the <2T from the start of the sequence and placing at the end - it can be considered a stop bit but I found it easier to deal with it at - the start). - -The 32 bits are encoded as XxYy where x and y are the actual data values -while X and Y are the logical inverses of the associated data values. Using -LSB first yields sensible codes for the numbers. - -All codes are of the form b9xx - -The numeric keys generate the code 0x where x is the number pressed. - -Tuner 1c -Tape 1d -CD 1e -CD-MD-CH 1f -Track- 0a -Track+ 0b -Rewind 0c -FF 0d -DNPP 5e -Play/Pause 0e -Vol+ 14 -Vol- 15 diff --git a/Documentation/arm/empeg/mkdevs b/Documentation/arm/empeg/mkdevs deleted file mode 100644 index 7a85e28d14f..00000000000 --- a/Documentation/arm/empeg/mkdevs +++ /dev/null @@ -1,11 +0,0 @@ -#!/bin/sh -mknod /dev/display c 244 0 -mknod /dev/ir c 242 0 -mknod /dev/usb0 c 243 0 -mknod /dev/audio c 245 4 -mknod /dev/dsp c 245 3 -mknod /dev/mixer c 245 0 -mknod /dev/empeg_state c 246 0 -mknod /dev/radio0 c 81 64 -ln -sf radio0 radio -ln -sf usb0 usb diff --git a/Documentation/arm/firmware.txt b/Documentation/arm/firmware.txt new file mode 100644 index 00000000000..c2e468fe7b0 --- /dev/null +++ b/Documentation/arm/firmware.txt @@ -0,0 +1,88 @@ +Interface for registering and calling firmware-specific operations for ARM. +---- +Written by Tomasz Figa <t.figa@samsung.com> + +Some boards are running with secure firmware running in TrustZone secure +world, which changes the way some things have to be initialized. This makes +a need to provide an interface for such platforms to specify available firmware +operations and call them when needed. + +Firmware operations can be specified using struct firmware_ops + + struct firmware_ops { + /* + * Enters CPU idle mode + */ + int (*do_idle)(void); + /* + * Sets boot address of specified physical CPU + */ + int (*set_cpu_boot_addr)(int cpu, unsigned long boot_addr); + /* + * Boots specified physical CPU + */ + int (*cpu_boot)(int cpu); + /* + * Initializes L2 cache + */ + int (*l2x0_init)(void); + }; + +and then registered with register_firmware_ops function + + void register_firmware_ops(const struct firmware_ops *ops) + +the ops pointer must be non-NULL. + +There is a default, empty set of operations provided, so there is no need to +set anything if platform does not require firmware operations. + +To call a firmware operation, a helper macro is provided + + #define call_firmware_op(op, ...) \ + ((firmware_ops->op) ? firmware_ops->op(__VA_ARGS__) : (-ENOSYS)) + +the macro checks if the operation is provided and calls it or otherwise returns +-ENOSYS to signal that given operation is not available (for example, to allow +fallback to legacy operation). + +Example of registering firmware operations: + + /* board file */ + + static int platformX_do_idle(void) + { + /* tell platformX firmware to enter idle */ + return 0; + } + + static int platformX_cpu_boot(int i) + { + /* tell platformX firmware to boot CPU i */ + return 0; + } + + static const struct firmware_ops platformX_firmware_ops = { + .do_idle = exynos_do_idle, + .cpu_boot = exynos_cpu_boot, + /* other operations not available on platformX */ + }; + + /* init_early callback of machine descriptor */ + static void __init board_init_early(void) + { + register_firmware_ops(&platformX_firmware_ops); + } + +Example of using a firmware operation: + + /* some platform code, e.g. SMP initialization */ + + __raw_writel(virt_to_phys(exynos4_secondary_startup), + CPU1_BOOT_REG); + + /* Call Exynos specific smc call */ + if (call_firmware_op(cpu_boot, cpu) == -ENOSYS) + cpu_boot_legacy(...); /* Try legacy way */ + + gic_raise_softirq(cpumask_of(cpu), 1); diff --git a/Documentation/arm/kernel_mode_neon.txt b/Documentation/arm/kernel_mode_neon.txt new file mode 100644 index 00000000000..525452726d3 --- /dev/null +++ b/Documentation/arm/kernel_mode_neon.txt @@ -0,0 +1,121 @@ +Kernel mode NEON +================ + +TL;DR summary +------------- +* Use only NEON instructions, or VFP instructions that don't rely on support + code +* Isolate your NEON code in a separate compilation unit, and compile it with + '-mfpu=neon -mfloat-abi=softfp' +* Put kernel_neon_begin() and kernel_neon_end() calls around the calls into your + NEON code +* Don't sleep in your NEON code, and be aware that it will be executed with + preemption disabled + + +Introduction +------------ +It is possible to use NEON instructions (and in some cases, VFP instructions) in +code that runs in kernel mode. However, for performance reasons, the NEON/VFP +register file is not preserved and restored at every context switch or taken +exception like the normal register file is, so some manual intervention is +required. Furthermore, special care is required for code that may sleep [i.e., +may call schedule()], as NEON or VFP instructions will be executed in a +non-preemptible section for reasons outlined below. + + +Lazy preserve and restore +------------------------- +The NEON/VFP register file is managed using lazy preserve (on UP systems) and +lazy restore (on both SMP and UP systems). This means that the register file is +kept 'live', and is only preserved and restored when multiple tasks are +contending for the NEON/VFP unit (or, in the SMP case, when a task migrates to +another core). Lazy restore is implemented by disabling the NEON/VFP unit after +every context switch, resulting in a trap when subsequently a NEON/VFP +instruction is issued, allowing the kernel to step in and perform the restore if +necessary. + +Any use of the NEON/VFP unit in kernel mode should not interfere with this, so +it is required to do an 'eager' preserve of the NEON/VFP register file, and +enable the NEON/VFP unit explicitly so no exceptions are generated on first +subsequent use. This is handled by the function kernel_neon_begin(), which +should be called before any kernel mode NEON or VFP instructions are issued. +Likewise, the NEON/VFP unit should be disabled again after use to make sure user +mode will hit the lazy restore trap upon next use. This is handled by the +function kernel_neon_end(). + + +Interruptions in kernel mode +---------------------------- +For reasons of performance and simplicity, it was decided that there shall be no +preserve/restore mechanism for the kernel mode NEON/VFP register contents. This +implies that interruptions of a kernel mode NEON section can only be allowed if +they are guaranteed not to touch the NEON/VFP registers. For this reason, the +following rules and restrictions apply in the kernel: +* NEON/VFP code is not allowed in interrupt context; +* NEON/VFP code is not allowed to sleep; +* NEON/VFP code is executed with preemption disabled. + +If latency is a concern, it is possible to put back to back calls to +kernel_neon_end() and kernel_neon_begin() in places in your code where none of +the NEON registers are live. (Additional calls to kernel_neon_begin() should be +reasonably cheap if no context switch occurred in the meantime) + + +VFP and support code +-------------------- +Earlier versions of VFP (prior to version 3) rely on software support for things +like IEEE-754 compliant underflow handling etc. When the VFP unit needs such +software assistance, it signals the kernel by raising an undefined instruction +exception. The kernel responds by inspecting the VFP control registers and the +current instruction and arguments, and emulates the instruction in software. + +Such software assistance is currently not implemented for VFP instructions +executed in kernel mode. If such a condition is encountered, the kernel will +fail and generate an OOPS. + + +Separating NEON code from ordinary code +--------------------------------------- +The compiler is not aware of the special significance of kernel_neon_begin() and +kernel_neon_end(), i.e., that it is only allowed to issue NEON/VFP instructions +between calls to these respective functions. Furthermore, GCC may generate NEON +instructions of its own at -O3 level if -mfpu=neon is selected, and even if the +kernel is currently compiled at -O2, future changes may result in NEON/VFP +instructions appearing in unexpected places if no special care is taken. + +Therefore, the recommended and only supported way of using NEON/VFP in the +kernel is by adhering to the following rules: +* isolate the NEON code in a separate compilation unit and compile it with + '-mfpu=neon -mfloat-abi=softfp'; +* issue the calls to kernel_neon_begin(), kernel_neon_end() as well as the calls + into the unit containing the NEON code from a compilation unit which is *not* + built with the GCC flag '-mfpu=neon' set. + +As the kernel is compiled with '-msoft-float', the above will guarantee that +both NEON and VFP instructions will only ever appear in designated compilation +units at any optimization level. + + +NEON assembler +-------------- +NEON assembler is supported with no additional caveats as long as the rules +above are followed. + + +NEON code generated by GCC +-------------------------- +The GCC option -ftree-vectorize (implied by -O3) tries to exploit implicit +parallelism, and generates NEON code from ordinary C source code. This is fully +supported as long as the rules above are followed. + + +NEON intrinsics +--------------- +NEON intrinsics are also supported. However, as code using NEON intrinsics +relies on the GCC header <arm_neon.h>, (which #includes <stdint.h>), you should +observe the following in addition to the rules above: +* Compile the unit containing the NEON intrinsics with '-ffreestanding' so GCC + uses its builtin version of <stdint.h> (this is a C99 header which the kernel + does not supply); +* Include <arm_neon.h> last, or at least after <linux/types.h> diff --git a/Documentation/arm/kernel_user_helpers.txt b/Documentation/arm/kernel_user_helpers.txt new file mode 100644 index 00000000000..5673594717c --- /dev/null +++ b/Documentation/arm/kernel_user_helpers.txt @@ -0,0 +1,267 @@ +Kernel-provided User Helpers +============================ + +These are segment of kernel provided user code reachable from user space +at a fixed address in kernel memory. This is used to provide user space +with some operations which require kernel help because of unimplemented +native feature and/or instructions in many ARM CPUs. The idea is for this +code to be executed directly in user mode for best efficiency but which is +too intimate with the kernel counter part to be left to user libraries. +In fact this code might even differ from one CPU to another depending on +the available instruction set, or whether it is a SMP systems. In other +words, the kernel reserves the right to change this code as needed without +warning. Only the entry points and their results as documented here are +guaranteed to be stable. + +This is different from (but doesn't preclude) a full blown VDSO +implementation, however a VDSO would prevent some assembly tricks with +constants that allows for efficient branching to those code segments. And +since those code segments only use a few cycles before returning to user +code, the overhead of a VDSO indirect far call would add a measurable +overhead to such minimalistic operations. + +User space is expected to bypass those helpers and implement those things +inline (either in the code emitted directly by the compiler, or part of +the implementation of a library call) when optimizing for a recent enough +processor that has the necessary native support, but only if resulting +binaries are already to be incompatible with earlier ARM processors due to +usage of similar native instructions for other things. In other words +don't make binaries unable to run on earlier processors just for the sake +of not using these kernel helpers if your compiled code is not going to +use new instructions for other purpose. + +New helpers may be added over time, so an older kernel may be missing some +helpers present in a newer kernel. For this reason, programs must check +the value of __kuser_helper_version (see below) before assuming that it is +safe to call any particular helper. This check should ideally be +performed only once at process startup time, and execution aborted early +if the required helpers are not provided by the kernel version that +process is running on. + +kuser_helper_version +-------------------- + +Location: 0xffff0ffc + +Reference declaration: + + extern int32_t __kuser_helper_version; + +Definition: + + This field contains the number of helpers being implemented by the + running kernel. User space may read this to determine the availability + of a particular helper. + +Usage example: + +#define __kuser_helper_version (*(int32_t *)0xffff0ffc) + +void check_kuser_version(void) +{ + if (__kuser_helper_version < 2) { + fprintf(stderr, "can't do atomic operations, kernel too old\n"); + abort(); + } +} + +Notes: + + User space may assume that the value of this field never changes + during the lifetime of any single process. This means that this + field can be read once during the initialisation of a library or + startup phase of a program. + +kuser_get_tls +------------- + +Location: 0xffff0fe0 + +Reference prototype: + + void * __kuser_get_tls(void); + +Input: + + lr = return address + +Output: + + r0 = TLS value + +Clobbered registers: + + none + +Definition: + + Get the TLS value as previously set via the __ARM_NR_set_tls syscall. + +Usage example: + +typedef void * (__kuser_get_tls_t)(void); +#define __kuser_get_tls (*(__kuser_get_tls_t *)0xffff0fe0) + +void foo() +{ + void *tls = __kuser_get_tls(); + printf("TLS = %p\n", tls); +} + +Notes: + + - Valid only if __kuser_helper_version >= 1 (from kernel version 2.6.12). + +kuser_cmpxchg +------------- + +Location: 0xffff0fc0 + +Reference prototype: + + int __kuser_cmpxchg(int32_t oldval, int32_t newval, volatile int32_t *ptr); + +Input: + + r0 = oldval + r1 = newval + r2 = ptr + lr = return address + +Output: + + r0 = success code (zero or non-zero) + C flag = set if r0 == 0, clear if r0 != 0 + +Clobbered registers: + + r3, ip, flags + +Definition: + + Atomically store newval in *ptr only if *ptr is equal to oldval. + Return zero if *ptr was changed or non-zero if no exchange happened. + The C flag is also set if *ptr was changed to allow for assembly + optimization in the calling code. + +Usage example: + +typedef int (__kuser_cmpxchg_t)(int oldval, int newval, volatile int *ptr); +#define __kuser_cmpxchg (*(__kuser_cmpxchg_t *)0xffff0fc0) + +int atomic_add(volatile int *ptr, int val) +{ + int old, new; + + do { + old = *ptr; + new = old + val; + } while(__kuser_cmpxchg(old, new, ptr)); + + return new; +} + +Notes: + + - This routine already includes memory barriers as needed. + + - Valid only if __kuser_helper_version >= 2 (from kernel version 2.6.12). + +kuser_memory_barrier +-------------------- + +Location: 0xffff0fa0 + +Reference prototype: + + void __kuser_memory_barrier(void); + +Input: + + lr = return address + +Output: + + none + +Clobbered registers: + + none + +Definition: + + Apply any needed memory barrier to preserve consistency with data modified + manually and __kuser_cmpxchg usage. + +Usage example: + +typedef void (__kuser_dmb_t)(void); +#define __kuser_dmb (*(__kuser_dmb_t *)0xffff0fa0) + +Notes: + + - Valid only if __kuser_helper_version >= 3 (from kernel version 2.6.15). + +kuser_cmpxchg64 +--------------- + +Location: 0xffff0f60 + +Reference prototype: + + int __kuser_cmpxchg64(const int64_t *oldval, + const int64_t *newval, + volatile int64_t *ptr); + +Input: + + r0 = pointer to oldval + r1 = pointer to newval + r2 = pointer to target value + lr = return address + +Output: + + r0 = success code (zero or non-zero) + C flag = set if r0 == 0, clear if r0 != 0 + +Clobbered registers: + + r3, lr, flags + +Definition: + + Atomically store the 64-bit value pointed by *newval in *ptr only if *ptr + is equal to the 64-bit value pointed by *oldval. Return zero if *ptr was + changed or non-zero if no exchange happened. + + The C flag is also set if *ptr was changed to allow for assembly + optimization in the calling code. + +Usage example: + +typedef int (__kuser_cmpxchg64_t)(const int64_t *oldval, + const int64_t *newval, + volatile int64_t *ptr); +#define __kuser_cmpxchg64 (*(__kuser_cmpxchg64_t *)0xffff0f60) + +int64_t atomic_add64(volatile int64_t *ptr, int64_t val) +{ + int64_t old, new; + + do { + old = *ptr; + new = old + val; + } while(__kuser_cmpxchg64(&old, &new, ptr)); + + return new; +} + +Notes: + + - This routine already includes memory barriers as needed. + + - Due to the length of this sequence, this spans 2 conventional kuser + "slots", therefore 0xffff0f80 is not used as a valid entry point. + + - Valid only if __kuser_helper_version >= 5 (from kernel version 3.1). diff --git a/Documentation/arm/mem_alignment b/Documentation/arm/mem_alignment index d145ccca169..c7c7a114c78 100644 --- a/Documentation/arm/mem_alignment +++ b/Documentation/arm/mem_alignment @@ -24,7 +24,7 @@ real bad - it changes the behaviour of all unaligned instructions in user space, and might cause programs to fail unexpectedly. To change the alignment trap behavior, simply echo a number into -/proc/sys/debug/alignment. The number is made up from various bits: +/proc/cpu/alignment. The number is made up from various bits: bit behavior when set --- ----------------- diff --git a/Documentation/arm/memory.txt b/Documentation/arm/memory.txt index dc6045577a8..38dc06d0a79 100644 --- a/Documentation/arm/memory.txt +++ b/Documentation/arm/memory.txt @@ -21,6 +21,8 @@ ffff8000 ffffffff copy_user_page / clear_user_page use. For SA11xx and Xscale, this is used to setup a minicache mapping. +ffff4000 ffffffff cache aliasing on ARMv6 and later CPUs. + ffff1000 ffff7fff Reserved. Platforms must not use this address range. @@ -29,28 +31,40 @@ ffff0000 ffff0fff CPU vector page. CPU supports vector relocation (control register V bit.) -ffc00000 fffeffff DMA memory mapping region. Memory returned - by the dma_alloc_xxx functions will be - dynamically mapped here. +fffe0000 fffeffff XScale cache flush area. This is used + in proc-xscale.S to flush the whole data + cache. (XScale does not have TCM.) + +fffe8000 fffeffff DTCM mapping area for platforms with + DTCM mounted inside the CPU. -ff000000 ffbfffff Reserved for future expansion of DMA - mapping region. +fffe0000 fffe7fff ITCM mapping area for platforms with + ITCM mounted inside the CPU. -VMALLOC_END feffffff Free for platform use, recommended. - VMALLOC_END must be aligned to a 2MB - boundary. +ffc00000 ffdfffff Fixmap mapping region. Addresses provided + by fix_to_virt() will be located here. + +fee00000 feffffff Mapping of PCI I/O space. This is a static + mapping within the vmalloc space. VMALLOC_START VMALLOC_END-1 vmalloc() / ioremap() space. Memory returned by vmalloc/ioremap will be dynamically placed in this region. - VMALLOC_START may be based upon the value - of the high_memory variable. + Machine specific static mappings are also + located here through iotable_init(). + VMALLOC_START is based upon the value + of the high_memory variable, and VMALLOC_END + is equal to 0xff000000. PAGE_OFFSET high_memory-1 Kernel direct-mapped RAM region. This maps the platforms RAM, and typically maps all platform RAM in a 1:1 relationship. -TASK_SIZE PAGE_OFFSET-1 Kernel module space +PKMAP_BASE PAGE_OFFSET-1 Permanent kernel mappings + One way of mapping HIGHMEM pages into kernel + space. + +MODULES_VADDR MODULES_END-1 Kernel module space Kernel modules inserted via insmod are placed here using dynamic mappings. diff --git a/Documentation/arm/msm/gpiomux.txt b/Documentation/arm/msm/gpiomux.txt new file mode 100644 index 00000000000..67a81620adf --- /dev/null +++ b/Documentation/arm/msm/gpiomux.txt @@ -0,0 +1,176 @@ +This document provides an overview of the msm_gpiomux interface, which +is used to provide gpio pin multiplexing and configuration on mach-msm +targets. + +History +======= + +The first-generation API for gpio configuration & multiplexing on msm +is the function gpio_tlmm_config(). This function has a few notable +shortcomings, which led to its deprecation and replacement by gpiomux: + +The 'disable' parameter: Setting the second parameter to +gpio_tlmm_config to GPIO_CFG_DISABLE tells the peripheral +processor in charge of the subsystem to perform a look-up into a +low-power table and apply the low-power/sleep setting for the pin. +As the msm family evolved this became problematic. Not all pins +have sleep settings, not all peripheral processors will accept requests +to apply said sleep settings, and not all msm targets have their gpio +subsystems managed by a peripheral processor. In order to get consistent +behavior on all targets, drivers are forced to ignore this parameter, +rendering it useless. + +The 'direction' flag: for all mux-settings other than raw-gpio (0), +the output-enable bit of a gpio is hard-wired to a known +input (usually VDD or ground). For those settings, the direction flag +is meaningless at best, and deceptive at worst. In addition, using the +direction flag to change output-enable (OE) directly can cause trouble in +gpiolib, which has no visibility into gpio direction changes made +in this way. Direction control in gpio mode should be made through gpiolib. + +Key Features of gpiomux +======================= + +- A consistent interface across all generations of msm. Drivers can expect +the same results on every target. +- gpiomux plays nicely with gpiolib. Functions that should belong to gpiolib +are left to gpiolib and not duplicated here. gpiomux is written with the +intent that gpio_chips will call gpiomux reference-counting methods +from their request() and free() hooks, providing full integration. +- Tabular configuration. Instead of having to call gpio_tlmm_config +hundreds of times, gpio configuration is placed in a single table. +- Per-gpio sleep. Each gpio is individually reference counted, allowing only +those lines which are in use to be put in high-power states. +- 0 means 'do nothing': all flags are designed so that the default memset-zero +equates to a sensible default of 'no configuration', preventing users +from having to provide hundreds of 'no-op' configs for unused or +unwanted lines. + +Usage +===== + +To use gpiomux, provide configuration information for relevant gpio lines +in the msm_gpiomux_configs table. Since a 0 equates to "unconfigured", +only those lines to be managed by gpiomux need to be specified. Here +is a completely fictional example: + +struct msm_gpiomux_config msm_gpiomux_configs[GPIOMUX_NGPIOS] = { + [12] = { + .active = GPIOMUX_VALID | GPIOMUX_DRV_8MA | GPIOMUX_FUNC_1, + .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, + }, + [34] = { + .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, + }, +}; + +To indicate that a gpio is in use, call msm_gpiomux_get() to increase +its reference count. To decrease the reference count, call msm_gpiomux_put(). + +The effect of this configuration is as follows: + +When the system boots, gpios 12 and 34 will be initialized with their +'suspended' configurations. All other gpios, which were left unconfigured, +will not be touched. + +When msm_gpiomux_get() is called on gpio 12 to raise its reference count +above 0, its active configuration will be applied. Since no other gpio +line has a valid active configuration, msm_gpiomux_get() will have no +effect on any other line. + +When msm_gpiomux_put() is called on gpio 12 or 34 to drop their reference +count to 0, their suspended configurations will be applied. +Since no other gpio line has a valid suspended configuration, no other +gpio line will be effected by msm_gpiomux_put(). Since gpio 34 has no valid +active configuration, this is effectively a no-op for gpio 34 as well, +with one small caveat, see the section "About Output-Enable Settings". + +All of the GPIOMUX_VALID flags may seem like unnecessary overhead, but +they address some important issues. As unused entries (all those +except 12 and 34) are zero-filled, gpiomux needs a way to distinguish +the used fields from the unused. In addition, the all-zero pattern +is a valid configuration! Therefore, gpiomux defines an additional bit +which is used to indicate when a field is used. This has the pleasant +side-effect of allowing calls to msm_gpiomux_write to use '0' to indicate +that a value should not be changed: + + msm_gpiomux_write(0, GPIOMUX_VALID, 0); + +replaces the active configuration of gpio 0 with an all-zero configuration, +but leaves the suspended configuration as it was. + +Static Configurations +===================== + +To install a static configuration, which is applied at boot and does +not change after that, install a configuration with a suspended component +but no active component, as in the previous example: + + [34] = { + .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, + }, + +The suspended setting is applied during boot, and the lack of any valid +active setting prevents any other setting from being applied at runtime. +If other subsystems attempting to access the line is a concern, one could +*really* anchor the configuration down by calling msm_gpiomux_get on the +line at initialization to move the line into active mode. With the line +held, it will never be re-suspended, and with no valid active configuration, +no new configurations will be applied. + +But then, if having other subsystems grabbing for the line is truly a concern, +it should be reserved with gpio_request instead, which carries an implicit +msm_gpiomux_get. + +gpiomux and gpiolib +=================== + +It is expected that msm gpio_chips will call msm_gpiomux_get() and +msm_gpiomux_put() from their request and free hooks, like this fictional +example: + +static int request(struct gpio_chip *chip, unsigned offset) +{ + return msm_gpiomux_get(chip->base + offset); +} + +static void free(struct gpio_chip *chip, unsigned offset) +{ + msm_gpiomux_put(chip->base + offset); +} + + ...somewhere in a gpio_chip declaration... + .request = request, + .free = free, + +This provides important functionality: +- It guarantees that a gpio line will have its 'active' config applied + when the line is requested, and will not be suspended while the line + remains requested; and +- It guarantees that gpio-direction settings from gpiolib behave sensibly. + See "About Output-Enable Settings." + +This mechanism allows for "auto-request" of gpiomux lines via gpiolib +when it is suitable. Drivers wishing more exact control are, of course, +free to also use msm_gpiomux_set and msm_gpiomux_get. + +About Output-Enable Settings +============================ + +Some msm targets do not have the ability to query the current gpio +configuration setting. This means that changes made to the output-enable +(OE) bit by gpiolib cannot be consistently detected and preserved by gpiomux. +Therefore, when gpiomux applies a configuration setting, any direction +settings which may have been applied by gpiolib are lost and the default +input settings are re-applied. + +For this reason, drivers should not assume that gpio direction settings +continue to hold if they free and then re-request a gpio. This seems like +common sense - after all, anybody could have obtained the line in the +meantime - but it needs saying. + +This also means that calls to msm_gpiomux_write will reset the OE bit, +which means that if the gpio line is held by a client of gpiolib and +msm_gpiomux_write is called, the direction setting has been lost and +gpiolib's internal state has been broken. +Release gpio lines before reconfiguring them. diff --git a/Documentation/arm/pxa/mfp.txt b/Documentation/arm/pxa/mfp.txt new file mode 100644 index 00000000000..a179e5bc02c --- /dev/null +++ b/Documentation/arm/pxa/mfp.txt @@ -0,0 +1,286 @@ + MFP Configuration for PXA2xx/PXA3xx Processors + + Eric Miao <eric.miao@marvell.com> + +MFP stands for Multi-Function Pin, which is the pin-mux logic on PXA3xx and +later PXA series processors. This document describes the existing MFP API, +and how board/platform driver authors could make use of it. + + Basic Concept +=============== + +Unlike the GPIO alternate function settings on PXA25x and PXA27x, a new MFP +mechanism is introduced from PXA3xx to completely move the pin-mux functions +out of the GPIO controller. In addition to pin-mux configurations, the MFP +also controls the low power state, driving strength, pull-up/down and event +detection of each pin. Below is a diagram of internal connections between +the MFP logic and the remaining SoC peripherals: + + +--------+ + | |--(GPIO19)--+ + | GPIO | | + | |--(GPIO...) | + +--------+ | + | +---------+ + +--------+ +------>| | + | PWM2 |--(PWM_OUT)-------->| MFP | + +--------+ +------>| |-------> to external PAD + | +---->| | + +--------+ | | +-->| | + | SSP2 |---(TXD)----+ | | +---------+ + +--------+ | | + | | + +--------+ | | + | Keypad |--(MKOUT4)----+ | + +--------+ | + | + +--------+ | + | UART2 |---(TXD)--------+ + +--------+ + +NOTE: the external pad is named as MFP_PIN_GPIO19, it doesn't necessarily +mean it's dedicated for GPIO19, only as a hint that internally this pin +can be routed from GPIO19 of the GPIO controller. + +To better understand the change from PXA25x/PXA27x GPIO alternate function +to this new MFP mechanism, here are several key points: + + 1. GPIO controller on PXA3xx is now a dedicated controller, same as other + internal controllers like PWM, SSP and UART, with 128 internal signals + which can be routed to external through one or more MFPs (e.g. GPIO<0> + can be routed through either MFP_PIN_GPIO0 as well as MFP_PIN_GPIO0_2, + see arch/arm/mach-pxa/mach/include/mfp-pxa300.h) + + 2. Alternate function configuration is removed from this GPIO controller, + the remaining functions are pure GPIO-specific, i.e. + + - GPIO signal level control + - GPIO direction control + - GPIO level change detection + + 3. Low power state for each pin is now controlled by MFP, this means the + PGSRx registers on PXA2xx are now useless on PXA3xx + + 4. Wakeup detection is now controlled by MFP, PWER does not control the + wakeup from GPIO(s) any more, depending on the sleeping state, ADxER + (as defined in pxa3xx-regs.h) controls the wakeup from MFP + +NOTE: with such a clear separation of MFP and GPIO, by GPIO<xx> we normally +mean it is a GPIO signal, and by MFP<xxx> or pin xxx, we mean a physical +pad (or ball). + + MFP API Usage +=============== + +For board code writers, here are some guidelines: + +1. include ONE of the following header files in your <board>.c: + + - #include <mach/mfp-pxa25x.h> + - #include <mach/mfp-pxa27x.h> + - #include <mach/mfp-pxa300.h> + - #include <mach/mfp-pxa320.h> + - #include <mach/mfp-pxa930.h> + + NOTE: only one file in your <board>.c, depending on the processors used, + because pin configuration definitions may conflict in these file (i.e. + same name, different meaning and settings on different processors). E.g. + for zylonite platform, which support both PXA300/PXA310 and PXA320, two + separate files are introduced: zylonite_pxa300.c and zylonite_pxa320.c + (in addition to handle MFP configuration differences, they also handle + the other differences between the two combinations). + + NOTE: PXA300 and PXA310 are almost identical in pin configurations (with + PXA310 supporting some additional ones), thus the difference is actually + covered in a single mfp-pxa300.h. + +2. prepare an array for the initial pin configurations, e.g.: + + static unsigned long mainstone_pin_config[] __initdata = { + /* Chip Select */ + GPIO15_nCS_1, + + /* LCD - 16bpp Active TFT */ + GPIOxx_TFT_LCD_16BPP, + GPIO16_PWM0_OUT, /* Backlight */ + + /* MMC */ + GPIO32_MMC_CLK, + GPIO112_MMC_CMD, + GPIO92_MMC_DAT_0, + GPIO109_MMC_DAT_1, + GPIO110_MMC_DAT_2, + GPIO111_MMC_DAT_3, + + ... + + /* GPIO */ + GPIO1_GPIO | WAKEUP_ON_EDGE_BOTH, + }; + + a) once the pin configurations are passed to pxa{2xx,3xx}_mfp_config(), + and written to the actual registers, they are useless and may discard, + adding '__initdata' will help save some additional bytes here. + + b) when there is only one possible pin configurations for a component, + some simplified definitions can be used, e.g. GPIOxx_TFT_LCD_16BPP on + PXA25x and PXA27x processors + + c) if by board design, a pin can be configured to wake up the system + from low power state, it can be 'OR'ed with any of: + + WAKEUP_ON_EDGE_BOTH + WAKEUP_ON_EDGE_RISE + WAKEUP_ON_EDGE_FALL + WAKEUP_ON_LEVEL_HIGH - specifically for enabling of keypad GPIOs, + + to indicate that this pin has the capability of wake-up the system, + and on which edge(s). This, however, doesn't necessarily mean the + pin _will_ wakeup the system, it will only when set_irq_wake() is + invoked with the corresponding GPIO IRQ (GPIO_IRQ(xx) or gpio_to_irq()) + and eventually calls gpio_set_wake() for the actual register setting. + + d) although PXA3xx MFP supports edge detection on each pin, the + internal logic will only wakeup the system when those specific bits + in ADxER registers are set, which can be well mapped to the + corresponding peripheral, thus set_irq_wake() can be called with + the peripheral IRQ to enable the wakeup. + + + MFP on PXA3xx +=============== + +Every external I/O pad on PXA3xx (excluding those for special purpose) has +one MFP logic associated, and is controlled by one MFP register (MFPR). + +The MFPR has the following bit definitions (for PXA300/PXA310/PXA320): + + 31 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 + +-------------------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + | RESERVED |PS|PU|PD| DRIVE |SS|SD|SO|EC|EF|ER|--| AF_SEL | + +-------------------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ + + Bit 3: RESERVED + Bit 4: EDGE_RISE_EN - enable detection of rising edge on this pin + Bit 5: EDGE_FALL_EN - enable detection of falling edge on this pin + Bit 6: EDGE_CLEAR - disable edge detection on this pin + Bit 7: SLEEP_OE_N - enable outputs during low power modes + Bit 8: SLEEP_DATA - output data on the pin during low power modes + Bit 9: SLEEP_SEL - selection control for low power modes signals + Bit 13: PULLDOWN_EN - enable the internal pull-down resistor on this pin + Bit 14: PULLUP_EN - enable the internal pull-up resistor on this pin + Bit 15: PULL_SEL - pull state controlled by selected alternate function + (0) or by PULL{UP,DOWN}_EN bits (1) + + Bit 0 - 2: AF_SEL - alternate function selection, 8 possibilities, from 0-7 + Bit 10-12: DRIVE - drive strength and slew rate + 0b000 - fast 1mA + 0b001 - fast 2mA + 0b002 - fast 3mA + 0b003 - fast 4mA + 0b004 - slow 6mA + 0b005 - fast 6mA + 0b006 - slow 10mA + 0b007 - fast 10mA + + MFP Design for PXA2xx/PXA3xx +============================== + +Due to the difference of pin-mux handling between PXA2xx and PXA3xx, a unified +MFP API is introduced to cover both series of processors. + +The basic idea of this design is to introduce definitions for all possible pin +configurations, these definitions are processor and platform independent, and +the actual API invoked to convert these definitions into register settings and +make them effective there-after. + + Files Involved + -------------- + + - arch/arm/mach-pxa/include/mach/mfp.h + + for + 1. Unified pin definitions - enum constants for all configurable pins + 2. processor-neutral bit definitions for a possible MFP configuration + + - arch/arm/mach-pxa/include/mach/mfp-pxa3xx.h + + for PXA3xx specific MFPR register bit definitions and PXA3xx common pin + configurations + + - arch/arm/mach-pxa/include/mach/mfp-pxa2xx.h + + for PXA2xx specific definitions and PXA25x/PXA27x common pin configurations + + - arch/arm/mach-pxa/include/mach/mfp-pxa25x.h + arch/arm/mach-pxa/include/mach/mfp-pxa27x.h + arch/arm/mach-pxa/include/mach/mfp-pxa300.h + arch/arm/mach-pxa/include/mach/mfp-pxa320.h + arch/arm/mach-pxa/include/mach/mfp-pxa930.h + + for processor specific definitions + + - arch/arm/mach-pxa/mfp-pxa3xx.c + - arch/arm/mach-pxa/mfp-pxa2xx.c + + for implementation of the pin configuration to take effect for the actual + processor. + + Pin Configuration + ----------------- + + The following comments are copied from mfp.h (see the actual source code + for most updated info) + + /* + * a possible MFP configuration is represented by a 32-bit integer + * + * bit 0.. 9 - MFP Pin Number (1024 Pins Maximum) + * bit 10..12 - Alternate Function Selection + * bit 13..15 - Drive Strength + * bit 16..18 - Low Power Mode State + * bit 19..20 - Low Power Mode Edge Detection + * bit 21..22 - Run Mode Pull State + * + * to facilitate the definition, the following macros are provided + * + * MFP_CFG_DEFAULT - default MFP configuration value, with + * alternate function = 0, + * drive strength = fast 3mA (MFP_DS03X) + * low power mode = default + * edge detection = none + * + * MFP_CFG - default MFPR value with alternate function + * MFP_CFG_DRV - default MFPR value with alternate function and + * pin drive strength + * MFP_CFG_LPM - default MFPR value with alternate function and + * low power mode + * MFP_CFG_X - default MFPR value with alternate function, + * pin drive strength and low power mode + */ + + Examples of pin configurations are: + + #define GPIO94_SSP3_RXD MFP_CFG_X(GPIO94, AF1, DS08X, FLOAT) + + which reads GPIO94 can be configured as SSP3_RXD, with alternate function + selection of 1, driving strength of 0b101, and a float state in low power + modes. + + NOTE: this is the default setting of this pin being configured as SSP3_RXD + which can be modified a bit in board code, though it is not recommended to + do so, simply because this default setting is usually carefully encoded, + and is supposed to work in most cases. + + Register Settings + ----------------- + + Register settings on PXA3xx for a pin configuration is actually very + straight-forward, most bits can be converted directly into MFPR value + in a easier way. Two sets of MFPR values are calculated: the run-time + ones and the low power mode ones, to allow different settings. + + The conversion from a generic pin configuration to the actual register + settings on PXA2xx is a bit complicated: many registers are involved, + including GAFRx, GPDRx, PGSRx, PWER, PKWR, PFER and PRER. Please see + mfp-pxa2xx.c for how the conversion is made. diff --git a/Documentation/arm/sti/overview.txt b/Documentation/arm/sti/overview.txt new file mode 100644 index 00000000000..1a4e93d6027 --- /dev/null +++ b/Documentation/arm/sti/overview.txt @@ -0,0 +1,33 @@ + STi ARM Linux Overview + ========================== + +Introduction +------------ + + The ST Microelectronics Multimedia and Application Processors range of + CortexA9 System-on-Chip are supported by the 'STi' platform of + ARM Linux. Currently STiH415, STiH416 SOCs are supported with both + B2000 and B2020 Reference boards. + + + configuration + ------------- + + A generic configuration is provided for both STiH415/416, and can be used as the + default by + make stih41x_defconfig + + Layout + ------ + All the files for multiple machine families (STiH415, STiH416, and STiG125) + are located in the platform code contained in arch/arm/mach-sti + + There is a generic board board-dt.c in the mach folder which support + Flattened Device Tree, which means, It works with any compatible board with + Device Trees. + + + Document Author + --------------- + + Srinivas Kandagatla <srinivas.kandagatla@st.com>, (c) 2013 ST Microelectronics diff --git a/Documentation/arm/sti/stih407-overview.txt b/Documentation/arm/sti/stih407-overview.txt new file mode 100644 index 00000000000..3343f32f58b --- /dev/null +++ b/Documentation/arm/sti/stih407-overview.txt @@ -0,0 +1,18 @@ + STiH407 Overview + ================ + +Introduction +------------ + + The STiH407 is the new generation of SoC for Multi-HD, AVC set-top boxes + and server/connected client application for satellite, cable, terrestrial + and IP-STB markets. + + Features + - ARM Cortex-A9 1.5 GHz dual core CPU (28nm) + - SATA2, USB 3.0, PCIe, Gbit Ethernet + + Document Author + --------------- + + Maxime Coquelin <maxime.coquelin@st.com>, (c) 2014 ST Microelectronics diff --git a/Documentation/arm/sti/stih415-overview.txt b/Documentation/arm/sti/stih415-overview.txt new file mode 100644 index 00000000000..1383e33f265 --- /dev/null +++ b/Documentation/arm/sti/stih415-overview.txt @@ -0,0 +1,12 @@ + STiH415 Overview + ================ + +Introduction +------------ + + The STiH415 is the next generation of HD, AVC set-top box processors + for satellite, cable, terrestrial and IP-STB markets. + + Features + - ARM Cortex-A9 1.0 GHz, dual-core CPU + - SATA2x2,USB 2.0x3, PCIe, Gbit Ethernet MACx2 diff --git a/Documentation/arm/sti/stih416-overview.txt b/Documentation/arm/sti/stih416-overview.txt new file mode 100644 index 00000000000..558444c201c --- /dev/null +++ b/Documentation/arm/sti/stih416-overview.txt @@ -0,0 +1,12 @@ + STiH416 Overview + ================ + +Introduction +------------ + + The STiH416 is the next generation of HD, AVC set-top box processors + for satellite, cable, terrestrial and IP-STB markets. + + Features + - ARM Cortex-A9 1.2 GHz dual core CPU + - SATA2x2,USB 2.0x3, PCIe, Gbit Ethernet MACx2 diff --git a/Documentation/arm/sunxi/README b/Documentation/arm/sunxi/README new file mode 100644 index 00000000000..7945238453e --- /dev/null +++ b/Documentation/arm/sunxi/README @@ -0,0 +1,52 @@ +ARM Allwinner SoCs +================== + +This document lists all the ARM Allwinner SoCs that are currently +supported in mainline by the Linux kernel. This document will also +provide links to documentation and/or datasheet for these SoCs. + +SunXi family +------------ + Linux kernel mach directory: arch/arm/mach-sunxi + + Flavors: + * ARM926 based SoCs + - Allwinner F20 (sun3i) + + Not Supported + + * ARM Cortex-A8 based SoCs + - Allwinner A10 (sun4i) + + Datasheet + http://dl.linux-sunxi.org/A10/A10%20Datasheet%20-%20v1.21%20%282012-04-06%29.pdf + + User Manual + http://dl.linux-sunxi.org/A10/A10%20User%20Manual%20-%20v1.20%20%282012-04-09%2c%20DECRYPTED%29.pdf + + - Allwinner A10s (sun5i) + + Datasheet + http://dl.linux-sunxi.org/A10s/A10s%20Datasheet%20-%20v1.20%20%282012-03-27%29.pdf + + - Allwinner A13 (sun5i) + + Datasheet + http://dl.linux-sunxi.org/A13/A13%20Datasheet%20-%20v1.12%20%282012-03-29%29.pdf + + User Manual + http://dl.linux-sunxi.org/A13/A13%20User%20Manual%20-%20v1.2%20%282013-01-08%29.pdf + + * Dual ARM Cortex-A7 based SoCs + - Allwinner A20 (sun7i) + + User Manual + http://dl.linux-sunxi.org/A20/A20%20User%20Manual%202013-03-22.pdf + + - Allwinner A23 + + Not Supported + + * Quad ARM Cortex-A7 based SoCs + - Allwinner A31 (sun6i) + + Datasheet + http://dl.linux-sunxi.org/A31/A31%20Datasheet%20-%20v1.00%20(2012-12-24).pdf + + - Allwinner A31s (sun6i) + + Not Supported + + * Quad ARM Cortex-A15, Quad ARM Cortex-A7 based SoCs + - Allwinner A80 + + Not Supported
\ No newline at end of file diff --git a/Documentation/arm/sunxi/clocks.txt b/Documentation/arm/sunxi/clocks.txt new file mode 100644 index 00000000000..e09a88aa313 --- /dev/null +++ b/Documentation/arm/sunxi/clocks.txt @@ -0,0 +1,56 @@ +Frequently asked questions about the sunxi clock system +======================================================= + +This document contains useful bits of information that people tend to ask +about the sunxi clock system, as well as accompanying ASCII art when adequate. + +Q: Why is the main 24MHz oscillator gatable? Wouldn't that break the + system? + +A: The 24MHz oscillator allows gating to save power. Indeed, if gated + carelessly the system would stop functioning, but with the right + steps, one can gate it and keep the system running. Consider this + simplified suspend example: + + While the system is operational, you would see something like + + 24MHz 32kHz + | + PLL1 + \ + \_ CPU Mux + | + [CPU] + + When you are about to suspend, you switch the CPU Mux to the 32kHz + oscillator: + + 24Mhz 32kHz + | | + PLL1 | + / + CPU Mux _/ + | + [CPU] + + Finally you can gate the main oscillator + + 32kHz + | + | + / + CPU Mux _/ + | + [CPU] + +Q: Were can I learn more about the sunxi clocks? + +A: The linux-sunxi wiki contains a page documenting the clock registers, + you can find it at + + http://linux-sunxi.org/A10/CCM + + The authoritative source for information at this time is the ccmu driver + released by Allwinner, you can find it at + + https://github.com/linux-sunxi/linux-sunxi/tree/sunxi-3.0/arch/arm/mach-sun4i/clock/ccmu diff --git a/Documentation/arm/swp_emulation b/Documentation/arm/swp_emulation new file mode 100644 index 00000000000..af903d22fd9 --- /dev/null +++ b/Documentation/arm/swp_emulation @@ -0,0 +1,27 @@ +Software emulation of deprecated SWP instruction (CONFIG_SWP_EMULATE) +--------------------------------------------------------------------- + +ARMv6 architecture deprecates use of the SWP/SWPB instructions, and recommeds +moving to the load-locked/store-conditional instructions LDREX and STREX. + +ARMv7 multiprocessing extensions introduce the ability to disable these +instructions, triggering an undefined instruction exception when executed. +Trapped instructions are emulated using an LDREX/STREX or LDREXB/STREXB +sequence. If a memory access fault (an abort) occurs, a segmentation fault is +signalled to the triggering process. + +/proc/cpu/swp_emulation holds some statistics/information, including the PID of +the last process to trigger the emulation to be invocated. For example: +--- +Emulated SWP: 12 +Emulated SWPB: 0 +Aborted SWP{B}: 1 +Last process: 314 +--- + +NOTE: when accessing uncached shared regions, LDREX/STREX rely on an external +transaction monitoring block called a global monitor to maintain update +atomicity. If your system does not implement a global monitor, this option can +cause programs that perform SWP operations to uncached memory to deadlock, as +the STREX operation will always fail. + diff --git a/Documentation/arm/tcm.txt b/Documentation/arm/tcm.txt new file mode 100644 index 00000000000..7c15871c188 --- /dev/null +++ b/Documentation/arm/tcm.txt @@ -0,0 +1,155 @@ +ARM TCM (Tightly-Coupled Memory) handling in Linux +---- +Written by Linus Walleij <linus.walleij@stericsson.com> + +Some ARM SoC:s have a so-called TCM (Tightly-Coupled Memory). +This is usually just a few (4-64) KiB of RAM inside the ARM +processor. + +Due to being embedded inside the CPU The TCM has a +Harvard-architecture, so there is an ITCM (instruction TCM) +and a DTCM (data TCM). The DTCM can not contain any +instructions, but the ITCM can actually contain data. +The size of DTCM or ITCM is minimum 4KiB so the typical +minimum configuration is 4KiB ITCM and 4KiB DTCM. + +ARM CPU:s have special registers to read out status, physical +location and size of TCM memories. arch/arm/include/asm/cputype.h +defines a CPUID_TCM register that you can read out from the +system control coprocessor. Documentation from ARM can be found +at http://infocenter.arm.com, search for "TCM Status Register" +to see documents for all CPUs. Reading this register you can +determine if ITCM (bits 1-0) and/or DTCM (bit 17-16) is present +in the machine. + +There is further a TCM region register (search for "TCM Region +Registers" at the ARM site) that can report and modify the location +size of TCM memories at runtime. This is used to read out and modify +TCM location and size. Notice that this is not a MMU table: you +actually move the physical location of the TCM around. At the +place you put it, it will mask any underlying RAM from the +CPU so it is usually wise not to overlap any physical RAM with +the TCM. + +The TCM memory can then be remapped to another address again using +the MMU, but notice that the TCM if often used in situations where +the MMU is turned off. To avoid confusion the current Linux +implementation will map the TCM 1 to 1 from physical to virtual +memory in the location specified by the kernel. Currently Linux +will map ITCM to 0xfffe0000 and on, and DTCM to 0xfffe8000 and +on, supporting a maximum of 32KiB of ITCM and 32KiB of DTCM. + +Newer versions of the region registers also support dividing these +TCMs in two separate banks, so for example an 8KiB ITCM is divided +into two 4KiB banks with its own control registers. The idea is to +be able to lock and hide one of the banks for use by the secure +world (TrustZone). + +TCM is used for a few things: + +- FIQ and other interrupt handlers that need deterministic + timing and cannot wait for cache misses. + +- Idle loops where all external RAM is set to self-refresh + retention mode, so only on-chip RAM is accessible by + the CPU and then we hang inside ITCM waiting for an + interrupt. + +- Other operations which implies shutting off or reconfiguring + the external RAM controller. + +There is an interface for using TCM on the ARM architecture +in <asm/tcm.h>. Using this interface it is possible to: + +- Define the physical address and size of ITCM and DTCM. + +- Tag functions to be compiled into ITCM. + +- Tag data and constants to be allocated to DTCM and ITCM. + +- Have the remaining TCM RAM added to a special + allocation pool with gen_pool_create() and gen_pool_add() + and provice tcm_alloc() and tcm_free() for this + memory. Such a heap is great for things like saving + device state when shutting off device power domains. + +A machine that has TCM memory shall select HAVE_TCM from +arch/arm/Kconfig for itself. Code that needs to use TCM shall +#include <asm/tcm.h> + +Functions to go into itcm can be tagged like this: +int __tcmfunc foo(int bar); + +Since these are marked to become long_calls and you may want +to have functions called locally inside the TCM without +wasting space, there is also the __tcmlocalfunc prefix that +will make the call relative. + +Variables to go into dtcm can be tagged like this: +int __tcmdata foo; + +Constants can be tagged like this: +int __tcmconst foo; + +To put assembler into TCM just use +.section ".tcm.text" or .section ".tcm.data" +respectively. + +Example code: + +#include <asm/tcm.h> + +/* Uninitialized data */ +static u32 __tcmdata tcmvar; +/* Initialized data */ +static u32 __tcmdata tcmassigned = 0x2BADBABEU; +/* Constant */ +static const u32 __tcmconst tcmconst = 0xCAFEBABEU; + +static void __tcmlocalfunc tcm_to_tcm(void) +{ + int i; + for (i = 0; i < 100; i++) + tcmvar ++; +} + +static void __tcmfunc hello_tcm(void) +{ + /* Some abstract code that runs in ITCM */ + int i; + for (i = 0; i < 100; i++) { + tcmvar ++; + } + tcm_to_tcm(); +} + +static void __init test_tcm(void) +{ + u32 *tcmem; + int i; + + hello_tcm(); + printk("Hello TCM executed from ITCM RAM\n"); + + printk("TCM variable from testrun: %u @ %p\n", tcmvar, &tcmvar); + tcmvar = 0xDEADBEEFU; + printk("TCM variable: 0x%x @ %p\n", tcmvar, &tcmvar); + + printk("TCM assigned variable: 0x%x @ %p\n", tcmassigned, &tcmassigned); + + printk("TCM constant: 0x%x @ %p\n", tcmconst, &tcmconst); + + /* Allocate some TCM memory from the pool */ + tcmem = tcm_alloc(20); + if (tcmem) { + printk("TCM Allocated 20 bytes of TCM @ %p\n", tcmem); + tcmem[0] = 0xDEADBEEFU; + tcmem[1] = 0x2BADBABEU; + tcmem[2] = 0xCAFEBABEU; + tcmem[3] = 0xDEADBEEFU; + tcmem[4] = 0x2BADBABEU; + for (i = 0; i < 5; i++) + printk("TCM tcmem[%d] = %08x\n", i, tcmem[i]); + tcm_free(tcmem, 20); + } +} diff --git a/Documentation/arm/uefi.txt b/Documentation/arm/uefi.txt new file mode 100644 index 00000000000..d60030a1b90 --- /dev/null +++ b/Documentation/arm/uefi.txt @@ -0,0 +1,64 @@ +UEFI, the Unified Extensible Firmware Interface, is a specification +governing the behaviours of compatible firmware interfaces. It is +maintained by the UEFI Forum - http://www.uefi.org/. + +UEFI is an evolution of its predecessor 'EFI', so the terms EFI and +UEFI are used somewhat interchangeably in this document and associated +source code. As a rule, anything new uses 'UEFI', whereas 'EFI' refers +to legacy code or specifications. + +UEFI support in Linux +===================== +Booting on a platform with firmware compliant with the UEFI specification +makes it possible for the kernel to support additional features: +- UEFI Runtime Services +- Retrieving various configuration information through the standardised + interface of UEFI configuration tables. (ACPI, SMBIOS, ...) + +For actually enabling [U]EFI support, enable: +- CONFIG_EFI=y +- CONFIG_EFI_VARS=y or m + +The implementation depends on receiving information about the UEFI environment +in a Flattened Device Tree (FDT) - so is only available with CONFIG_OF. + +UEFI stub +========= +The "stub" is a feature that extends the Image/zImage into a valid UEFI +PE/COFF executable, including a loader application that makes it possible to +load the kernel directly from the UEFI shell, boot menu, or one of the +lightweight bootloaders like Gummiboot or rEFInd. + +The kernel image built with stub support remains a valid kernel image for +booting in non-UEFI environments. + +UEFI kernel support on ARM +========================== +UEFI kernel support on the ARM architectures (arm and arm64) is only available +when boot is performed through the stub. + +When booting in UEFI mode, the stub deletes any memory nodes from a provided DT. +Instead, the kernel reads the UEFI memory map. + +The stub populates the FDT /chosen node with (and the kernel scans for) the +following parameters: +________________________________________________________________________________ +Name | Size | Description +================================================================================ +linux,uefi-system-table | 64-bit | Physical address of the UEFI System Table. +-------------------------------------------------------------------------------- +linux,uefi-mmap-start | 64-bit | Physical address of the UEFI memory map, + | | populated by the UEFI GetMemoryMap() call. +-------------------------------------------------------------------------------- +linux,uefi-mmap-size | 32-bit | Size in bytes of the UEFI memory map + | | pointed to in previous entry. +-------------------------------------------------------------------------------- +linux,uefi-mmap-desc-size | 32-bit | Size in bytes of each entry in the UEFI + | | memory map. +-------------------------------------------------------------------------------- +linux,uefi-mmap-desc-ver | 32-bit | Version of the mmap descriptor format. +-------------------------------------------------------------------------------- +linux,uefi-stub-kern-ver | string | Copy of linux_banner from build. +-------------------------------------------------------------------------------- + +For verbose debug messages, specify 'uefi_debug' on the kernel command line. diff --git a/Documentation/arm/vlocks.txt b/Documentation/arm/vlocks.txt new file mode 100644 index 00000000000..415960a9bab --- /dev/null +++ b/Documentation/arm/vlocks.txt @@ -0,0 +1,211 @@ +vlocks for Bare-Metal Mutual Exclusion +====================================== + +Voting Locks, or "vlocks" provide a simple low-level mutual exclusion +mechanism, with reasonable but minimal requirements on the memory +system. + +These are intended to be used to coordinate critical activity among CPUs +which are otherwise non-coherent, in situations where the hardware +provides no other mechanism to support this and ordinary spinlocks +cannot be used. + + +vlocks make use of the atomicity provided by the memory system for +writes to a single memory location. To arbitrate, every CPU "votes for +itself", by storing a unique number to a common memory location. The +final value seen in that memory location when all the votes have been +cast identifies the winner. + +In order to make sure that the election produces an unambiguous result +in finite time, a CPU will only enter the election in the first place if +no winner has been chosen and the election does not appear to have +started yet. + + +Algorithm +--------- + +The easiest way to explain the vlocks algorithm is with some pseudo-code: + + + int currently_voting[NR_CPUS] = { 0, }; + int last_vote = -1; /* no votes yet */ + + bool vlock_trylock(int this_cpu) + { + /* signal our desire to vote */ + currently_voting[this_cpu] = 1; + if (last_vote != -1) { + /* someone already volunteered himself */ + currently_voting[this_cpu] = 0; + return false; /* not ourself */ + } + + /* let's suggest ourself */ + last_vote = this_cpu; + currently_voting[this_cpu] = 0; + + /* then wait until everyone else is done voting */ + for_each_cpu(i) { + while (currently_voting[i] != 0) + /* wait */; + } + + /* result */ + if (last_vote == this_cpu) + return true; /* we won */ + return false; + } + + bool vlock_unlock(void) + { + last_vote = -1; + } + + +The currently_voting[] array provides a way for the CPUs to determine +whether an election is in progress, and plays a role analogous to the +"entering" array in Lamport's bakery algorithm [1]. + +However, once the election has started, the underlying memory system +atomicity is used to pick the winner. This avoids the need for a static +priority rule to act as a tie-breaker, or any counters which could +overflow. + +As long as the last_vote variable is globally visible to all CPUs, it +will contain only one value that won't change once every CPU has cleared +its currently_voting flag. + + +Features and limitations +------------------------ + + * vlocks are not intended to be fair. In the contended case, it is the + _last_ CPU which attempts to get the lock which will be most likely + to win. + + vlocks are therefore best suited to situations where it is necessary + to pick a unique winner, but it does not matter which CPU actually + wins. + + * Like other similar mechanisms, vlocks will not scale well to a large + number of CPUs. + + vlocks can be cascaded in a voting hierarchy to permit better scaling + if necessary, as in the following hypothetical example for 4096 CPUs: + + /* first level: local election */ + my_town = towns[(this_cpu >> 4) & 0xf]; + I_won = vlock_trylock(my_town, this_cpu & 0xf); + if (I_won) { + /* we won the town election, let's go for the state */ + my_state = states[(this_cpu >> 8) & 0xf]; + I_won = vlock_lock(my_state, this_cpu & 0xf)); + if (I_won) { + /* and so on */ + I_won = vlock_lock(the_whole_country, this_cpu & 0xf]; + if (I_won) { + /* ... */ + } + vlock_unlock(the_whole_country); + } + vlock_unlock(my_state); + } + vlock_unlock(my_town); + + +ARM implementation +------------------ + +The current ARM implementation [2] contains some optimisations beyond +the basic algorithm: + + * By packing the members of the currently_voting array close together, + we can read the whole array in one transaction (providing the number + of CPUs potentially contending the lock is small enough). This + reduces the number of round-trips required to external memory. + + In the ARM implementation, this means that we can use a single load + and comparison: + + LDR Rt, [Rn] + CMP Rt, #0 + + ...in place of code equivalent to: + + LDRB Rt, [Rn] + CMP Rt, #0 + LDRBEQ Rt, [Rn, #1] + CMPEQ Rt, #0 + LDRBEQ Rt, [Rn, #2] + CMPEQ Rt, #0 + LDRBEQ Rt, [Rn, #3] + CMPEQ Rt, #0 + + This cuts down on the fast-path latency, as well as potentially + reducing bus contention in contended cases. + + The optimisation relies on the fact that the ARM memory system + guarantees coherency between overlapping memory accesses of + different sizes, similarly to many other architectures. Note that + we do not care which element of currently_voting appears in which + bits of Rt, so there is no need to worry about endianness in this + optimisation. + + If there are too many CPUs to read the currently_voting array in + one transaction then multiple transations are still required. The + implementation uses a simple loop of word-sized loads for this + case. The number of transactions is still fewer than would be + required if bytes were loaded individually. + + + In principle, we could aggregate further by using LDRD or LDM, but + to keep the code simple this was not attempted in the initial + implementation. + + + * vlocks are currently only used to coordinate between CPUs which are + unable to enable their caches yet. This means that the + implementation removes many of the barriers which would be required + when executing the algorithm in cached memory. + + packing of the currently_voting array does not work with cached + memory unless all CPUs contending the lock are cache-coherent, due + to cache writebacks from one CPU clobbering values written by other + CPUs. (Though if all the CPUs are cache-coherent, you should be + probably be using proper spinlocks instead anyway). + + + * The "no votes yet" value used for the last_vote variable is 0 (not + -1 as in the pseudocode). This allows statically-allocated vlocks + to be implicitly initialised to an unlocked state simply by putting + them in .bss. + + An offset is added to each CPU's ID for the purpose of setting this + variable, so that no CPU uses the value 0 for its ID. + + +Colophon +-------- + +Originally created and documented by Dave Martin for Linaro Limited, for +use in ARM-based big.LITTLE platforms, with review and input gratefully +received from Nicolas Pitre and Achin Gupta. Thanks to Nicolas for +grabbing most of this text out of the relevant mail thread and writing +up the pseudocode. + +Copyright (C) 2012-2013 Linaro Limited +Distributed under the terms of Version 2 of the GNU General Public +License, as defined in linux/COPYING. + + +References +---------- + +[1] Lamport, L. "A New Solution of Dijkstra's Concurrent Programming + Problem", Communications of the ACM 17, 8 (August 1974), 453-455. + + http://en.wikipedia.org/wiki/Lamport%27s_bakery_algorithm + +[2] linux/arch/arm/common/vlock.S, www.kernel.org. |
