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Diffstat (limited to 'Documentation')
32 files changed, 2016 insertions, 39 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-dm b/Documentation/ABI/testing/sysfs-block-dm new file mode 100644 index 00000000000..87ca5691e29 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-block-dm @@ -0,0 +1,25 @@ +What: /sys/block/dm-<num>/dm/name +Date: January 2009 +KernelVersion: 2.6.29 +Contact: dm-devel@redhat.com +Description: Device-mapper device name. + Read-only string containing mapped device name. +Users: util-linux, device-mapper udev rules + +What: /sys/block/dm-<num>/dm/uuid +Date: January 2009 +KernelVersion: 2.6.29 +Contact: dm-devel@redhat.com +Description: Device-mapper device UUID. + Read-only string containing DM-UUID or empty string + if DM-UUID is not set. +Users: util-linux, device-mapper udev rules + +What: /sys/block/dm-<num>/dm/suspended +Date: June 2009 +KernelVersion: 2.6.31 +Contact: dm-devel@redhat.com +Description: Device-mapper device suspend state. + Contains the value 1 while the device is suspended. + Otherwise it contains 0. Read-only attribute. +Users: util-linux, device-mapper udev rules diff --git a/Documentation/ABI/testing/sysfs-bus-rpmsg b/Documentation/ABI/testing/sysfs-bus-rpmsg new file mode 100644 index 00000000000..189e419a5a2 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-rpmsg @@ -0,0 +1,75 @@ +What: /sys/bus/rpmsg/devices/.../name +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen <ohad@wizery.com> +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels are identified with a (textual) name, + which is maximum 32 bytes long (defined as RPMSG_NAME_SIZE in + rpmsg.h). + + This sysfs entry contains the name of this channel. + +What: /sys/bus/rpmsg/devices/.../src +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen <ohad@wizery.com> +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels have a local ("source") rpmsg address, + and remote ("destination") rpmsg address. When an entity + starts listening on one end of a channel, it assigns it with + a unique rpmsg address (a 32 bits integer). This way when + inbound messages arrive to this address, the rpmsg core + dispatches them to the listening entity (a kernel driver). + + This sysfs entry contains the src (local) rpmsg address + of this channel. If it contains 0xffffffff, then an address + wasn't assigned (can happen if no driver exists for this + channel). + +What: /sys/bus/rpmsg/devices/.../dst +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen <ohad@wizery.com> +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels have a local ("source") rpmsg address, + and remote ("destination") rpmsg address. When an entity + starts listening on one end of a channel, it assigns it with + a unique rpmsg address (a 32 bits integer). This way when + inbound messages arrive to this address, the rpmsg core + dispatches them to the listening entity. + + This sysfs entry contains the dst (remote) rpmsg address + of this channel. If it contains 0xffffffff, then an address + wasn't assigned (can happen if the kernel driver that + is attached to this channel is exposing a service to the + remote processor. This make it a local rpmsg server, + and it is listening for inbound messages that may be sent + from any remote rpmsg client; it is not bound to a single + remote entity). + +What: /sys/bus/rpmsg/devices/.../announce +Date: June 2011 +KernelVersion: 3.3 +Contact: Ohad Ben-Cohen <ohad@wizery.com> +Description: + Every rpmsg device is a communication channel with a remote + processor. Channels are identified by a textual name (see + /sys/bus/rpmsg/devices/.../name above) and have a local + ("source") rpmsg address, and remote ("destination") rpmsg + address. + + A channel is first created when an entity, whether local + or remote, starts listening on it for messages (and is thus + called an rpmsg server). + + When that happens, a "name service" announcement is sent + to the other processor, in order to let it know about the + creation of the channel (this way remote clients know they + can start sending messages). + + This sysfs entry tells us whether the channel is a local + server channel that is announced (values are either + true or false). diff --git a/Documentation/clk.txt b/Documentation/clk.txt new file mode 100644 index 00000000000..1943fae014f --- /dev/null +++ b/Documentation/clk.txt @@ -0,0 +1,233 @@ + The Common Clk Framework + Mike Turquette <mturquette@ti.com> + +This document endeavours to explain the common clk framework details, +and how to port a platform over to this framework. It is not yet a +detailed explanation of the clock api in include/linux/clk.h, but +perhaps someday it will include that information. + + Part 1 - introduction and interface split + +The common clk framework is an interface to control the clock nodes +available on various devices today. This may come in the form of clock +gating, rate adjustment, muxing or other operations. This framework is +enabled with the CONFIG_COMMON_CLK option. + +The interface itself is divided into two halves, each shielded from the +details of its counterpart. First is the common definition of struct +clk which unifies the framework-level accounting and infrastructure that +has traditionally been duplicated across a variety of platforms. Second +is a common implementation of the clk.h api, defined in +drivers/clk/clk.c. Finally there is struct clk_ops, whose operations +are invoked by the clk api implementation. + +The second half of the interface is comprised of the hardware-specific +callbacks registered with struct clk_ops and the corresponding +hardware-specific structures needed to model a particular clock. For +the remainder of this document any reference to a callback in struct +clk_ops, such as .enable or .set_rate, implies the hardware-specific +implementation of that code. Likewise, references to struct clk_foo +serve as a convenient shorthand for the implementation of the +hardware-specific bits for the hypothetical "foo" hardware. + +Tying the two halves of this interface together is struct clk_hw, which +is defined in struct clk_foo and pointed to within struct clk. This +allows easy for navigation between the two discrete halves of the common +clock interface. + + Part 2 - common data structures and api + +Below is the common struct clk definition from +include/linux/clk-private.h, modified for brevity: + + struct clk { + const char *name; + const struct clk_ops *ops; + struct clk_hw *hw; + char **parent_names; + struct clk **parents; + struct clk *parent; + struct hlist_head children; + struct hlist_node child_node; + ... + }; + +The members above make up the core of the clk tree topology. The clk +api itself defines several driver-facing functions which operate on +struct clk. That api is documented in include/linux/clk.h. + +Platforms and devices utilizing the common struct clk use the struct +clk_ops pointer in struct clk to perform the hardware-specific parts of +the operations defined in clk.h: + + struct clk_ops { + int (*prepare)(struct clk_hw *hw); + void (*unprepare)(struct clk_hw *hw); + int (*enable)(struct clk_hw *hw); + void (*disable)(struct clk_hw *hw); + int (*is_enabled)(struct clk_hw *hw); + unsigned long (*recalc_rate)(struct clk_hw *hw, + unsigned long parent_rate); + long (*round_rate)(struct clk_hw *hw, unsigned long, + unsigned long *); + int (*set_parent)(struct clk_hw *hw, u8 index); + u8 (*get_parent)(struct clk_hw *hw); + int (*set_rate)(struct clk_hw *hw, unsigned long); + void (*init)(struct clk_hw *hw); + }; + + Part 3 - hardware clk implementations + +The strength of the common struct clk comes from its .ops and .hw pointers +which abstract the details of struct clk from the hardware-specific bits, and +vice versa. To illustrate consider the simple gateable clk implementation in +drivers/clk/clk-gate.c: + +struct clk_gate { + struct clk_hw hw; + void __iomem *reg; + u8 bit_idx; + ... +}; + +struct clk_gate contains struct clk_hw hw as well as hardware-specific +knowledge about which register and bit controls this clk's gating. +Nothing about clock topology or accounting, such as enable_count or +notifier_count, is needed here. That is all handled by the common +framework code and struct clk. + +Let's walk through enabling this clk from driver code: + + struct clk *clk; + clk = clk_get(NULL, "my_gateable_clk"); + + clk_prepare(clk); + clk_enable(clk); + +The call graph for clk_enable is very simple: + +clk_enable(clk); + clk->ops->enable(clk->hw); + [resolves to...] + clk_gate_enable(hw); + [resolves struct clk gate with to_clk_gate(hw)] + clk_gate_set_bit(gate); + +And the definition of clk_gate_set_bit: + +static void clk_gate_set_bit(struct clk_gate *gate) +{ + u32 reg; + + reg = __raw_readl(gate->reg); + reg |= BIT(gate->bit_idx); + writel(reg, gate->reg); +} + +Note that to_clk_gate is defined as: + +#define to_clk_gate(_hw) container_of(_hw, struct clk_gate, clk) + +This pattern of abstraction is used for every clock hardware +representation. + + Part 4 - supporting your own clk hardware + +When implementing support for a new type of clock it only necessary to +include the following header: + +#include <linux/clk-provider.h> + +include/linux/clk.h is included within that header and clk-private.h +must never be included from the code which implements the operations for +a clock. More on that below in Part 5. + +To construct a clk hardware structure for your platform you must define +the following: + +struct clk_foo { + struct clk_hw hw; + ... hardware specific data goes here ... +}; + +To take advantage of your data you'll need to support valid operations +for your clk: + +struct clk_ops clk_foo_ops { + .enable = &clk_foo_enable; + .disable = &clk_foo_disable; +}; + +Implement the above functions using container_of: + +#define to_clk_foo(_hw) container_of(_hw, struct clk_foo, hw) + +int clk_foo_enable(struct clk_hw *hw) +{ + struct clk_foo *foo; + + foo = to_clk_foo(hw); + + ... perform magic on foo ... + + return 0; +}; + +Below is a matrix detailing which clk_ops are mandatory based upon the +hardware capbilities of that clock. A cell marked as "y" means +mandatory, a cell marked as "n" implies that either including that +callback is invalid or otherwise uneccesary. Empty cells are either +optional or must be evaluated on a case-by-case basis. + + clock hardware characteristics + ----------------------------------------------------------- + | gate | change rate | single parent | multiplexer | root | + |------|-------------|---------------|-------------|------| +.prepare | | | | | | +.unprepare | | | | | | + | | | | | | +.enable | y | | | | | +.disable | y | | | | | +.is_enabled | y | | | | | + | | | | | | +.recalc_rate | | y | | | | +.round_rate | | y | | | | +.set_rate | | y | | | | + | | | | | | +.set_parent | | | n | y | n | +.get_parent | | | n | y | n | + | | | | | | +.init | | | | | | + ----------------------------------------------------------- + +Finally, register your clock at run-time with a hardware-specific +registration function. This function simply populates struct clk_foo's +data and then passes the common struct clk parameters to the framework +with a call to: + +clk_register(...) + +See the basic clock types in drivers/clk/clk-*.c for examples. + + Part 5 - static initialization of clock data + +For platforms with many clocks (often numbering into the hundreds) it +may be desirable to statically initialize some clock data. This +presents a problem since the definition of struct clk should be hidden +from everyone except for the clock core in drivers/clk/clk.c. + +To get around this problem struct clk's definition is exposed in +include/linux/clk-private.h along with some macros for more easily +initializing instances of the basic clock types. These clocks must +still be initialized with the common clock framework via a call to +__clk_init. + +clk-private.h must NEVER be included by code which implements struct +clk_ops callbacks, nor must it be included by any logic which pokes +around inside of struct clk at run-time. To do so is a layering +violation. + +To better enforce this policy, always follow this simple rule: any +statically initialized clock data MUST be defined in a separate file +from the logic that implements its ops. Basically separate the logic +from the data and all is well. diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt index 1ff044d87ca..3370bc4d7b9 100644 --- a/Documentation/device-mapper/thin-provisioning.txt +++ b/Documentation/device-mapper/thin-provisioning.txt @@ -75,10 +75,12 @@ less sharing than average you'll need a larger-than-average metadata device. As a guide, we suggest you calculate the number of bytes to use in the metadata device as 48 * $data_dev_size / $data_block_size but round it up -to 2MB if the answer is smaller. The largest size supported is 16GB. +to 2MB if the answer is smaller. If you're creating large numbers of +snapshots which are recording large amounts of change, you may find you +need to increase this. -If you're creating large numbers of snapshots which are recording large -amounts of change, you may need find you need to increase this. +The largest size supported is 16GB: If the device is larger, +a warning will be issued and the excess space will not be used. Reloading a pool table ---------------------- @@ -167,6 +169,38 @@ ii) Using an internal snapshot. dmsetup create snap --table "0 2097152 thin /dev/mapper/pool 1" +External snapshots +------------------ + +You can use an external _read only_ device as an origin for a +thinly-provisioned volume. Any read to an unprovisioned area of the +thin device will be passed through to the origin. Writes trigger +the allocation of new blocks as usual. + +One use case for this is VM hosts that want to run guests on +thinly-provisioned volumes but have the base image on another device +(possibly shared between many VMs). + +You must not write to the origin device if you use this technique! +Of course, you may write to the thin device and take internal snapshots +of the thin volume. + +i) Creating a snapshot of an external device + + This is the same as creating a thin device. + You don't mention the origin at this stage. + + dmsetup message /dev/mapper/pool 0 "create_thin 0" + +ii) Using a snapshot of an external device. + + Append an extra parameter to the thin target specifying the origin: + + dmsetup create snap --table "0 2097152 thin /dev/mapper/pool 0 /dev/image" + + N.B. All descendants (internal snapshots) of this snapshot require the + same extra origin parameter. + Deactivation ------------ @@ -189,7 +223,13 @@ i) Constructor <low water mark (blocks)> [<number of feature args> [<arg>]*] Optional feature arguments: - - 'skip_block_zeroing': skips the zeroing of newly-provisioned blocks. + + skip_block_zeroing: Skip the zeroing of newly-provisioned blocks. + + ignore_discard: Disable discard support. + + no_discard_passdown: Don't pass discards down to the underlying + data device, but just remove the mapping. Data block size must be between 64KB (128 sectors) and 1GB (2097152 sectors) inclusive. @@ -237,16 +277,6 @@ iii) Messages Deletes a thin device. Irreversible. - trim <dev id> <new size in sectors> - - Delete mappings from the end of a thin device. Irreversible. - You might want to use this if you're reducing the size of - your thinly-provisioned device. In many cases, due to the - sharing of blocks between devices, it is not possible to - determine in advance how much space 'trim' will release. (In - future a userspace tool might be able to perform this - calculation.) - set_transaction_id <current id> <new id> Userland volume managers, such as LVM, need a way to @@ -262,7 +292,7 @@ iii) Messages i) Constructor - thin <pool dev> <dev id> + thin <pool dev> <dev id> [<external origin dev>] pool dev: the thin-pool device, e.g. /dev/mapper/my_pool or 253:0 @@ -271,6 +301,11 @@ i) Constructor the internal device identifier of the device to be activated. + external origin dev: + an optional block device outside the pool to be treated as a + read-only snapshot origin: reads to unprovisioned areas of the + thin target will be mapped to this device. + The pool doesn't store any size against the thin devices. If you load a thin target that is smaller than you've been using previously, then you'll have no access to blocks mapped beyond the end. If you diff --git a/Documentation/device-mapper/verity.txt b/Documentation/device-mapper/verity.txt new file mode 100644 index 00000000000..32e48797a14 --- /dev/null +++ b/Documentation/device-mapper/verity.txt @@ -0,0 +1,194 @@ +dm-verity +========== + +Device-Mapper's "verity" target provides transparent integrity checking of +block devices using a cryptographic digest provided by the kernel crypto API. +This target is read-only. + +Construction Parameters +======================= + <version> <dev> <hash_dev> <hash_start> + <data_block_size> <hash_block_size> + <num_data_blocks> <hash_start_block> + <algorithm> <digest> <salt> + +<version> + This is the version number of the on-disk format. + + 0 is the original format used in the Chromium OS. + The salt is appended when hashing, digests are stored continuously and + the rest of the block is padded with zeros. + + 1 is the current format that should be used for new devices. + The salt is prepended when hashing and each digest is + padded with zeros to the power of two. + +<dev> + This is the device containing the data the integrity of which needs to be + checked. It may be specified as a path, like /dev/sdaX, or a device number, + <major>:<minor>. + +<hash_dev> + This is the device that that supplies the hash tree data. It may be + specified similarly to the device path and may be the same device. If the + same device is used, the hash_start should be outside of the dm-verity + configured device size. + +<data_block_size> + The block size on a data device. Each block corresponds to one digest on + the hash device. + +<hash_block_size> + The size of a hash block. + +<num_data_blocks> + The number of data blocks on the data device. Additional blocks are + inaccessible. You can place hashes to the same partition as data, in this + case hashes are placed after <num_data_blocks>. + +<hash_start_block> + This is the offset, in <hash_block_size>-blocks, from the start of hash_dev + to the root block of the hash tree. + +<algorithm> + The cryptographic hash algorithm used for this device. This should + be the name of the algorithm, like "sha1". + +<digest> + The hexadecimal encoding of the cryptographic hash of the root hash block + and the salt. This hash should be trusted as there is no other authenticity + beyond this point. + +<salt> + The hexadecimal encoding of the salt value. + +Theory of operation +=================== + +dm-verity is meant to be setup as part of a verified boot path. This +may be anything ranging from a boot using tboot or trustedgrub to just +booting from a known-good device (like a USB drive or CD). + +When a dm-verity device is configured, it is expected that the caller +has been authenticated in some way (cryptographic signatures, etc). +After instantiation, all hashes will be verified on-demand during +disk access. If they cannot be verified up to the root node of the +tree, the root hash, then the I/O will fail. This should identify +tampering with any data on the device and the hash data. + +Cryptographic hashes are used to assert the integrity of the device on a +per-block basis. This allows for a lightweight hash computation on first read +into the page cache. Block hashes are stored linearly-aligned to the nearest +block the size of a page. + +Hash Tree +--------- + +Each node in the tree is a cryptographic hash. If it is a leaf node, the hash +is of some block data on disk. If it is an intermediary node, then the hash is +of a number of child nodes. + +Each entry in the tree is a collection of neighboring nodes that fit in one +block. The number is determined based on block_size and the size of the +selected cryptographic digest algorithm. The hashes are linearly-ordered in +this entry and any unaligned trailing space is ignored but included when +calculating the parent node. + +The tree looks something like: + +alg = sha256, num_blocks = 32768, block_size = 4096 + + [ root ] + / . . . \ + [entry_0] [entry_1] + / . . . \ . . . \ + [entry_0_0] . . . [entry_0_127] . . . . [entry_1_127] + / ... \ / . . . \ / \ + blk_0 ... blk_127 blk_16256 blk_16383 blk_32640 . . . blk_32767 + + +On-disk format +============== + +Below is the recommended on-disk format. The verity kernel code does not +read the on-disk header. It only reads the hash blocks which directly +follow the header. It is expected that a user-space tool will verify the +integrity of the verity_header and then call dmsetup with the correct +parameters. Alternatively, the header can be omitted and the dmsetup +parameters can be passed via the kernel command-line in a rooted chain +of trust where the command-line is verified. + +The on-disk format is especially useful in cases where the hash blocks +are on a separate partition. The magic number allows easy identification +of the partition contents. Alternatively, the hash blocks can be stored +in the same partition as the data to be verified. In such a configuration +the filesystem on the partition would be sized a little smaller than +the full-partition, leaving room for the hash blocks. + +struct superblock { + uint8_t signature[8] + "verity\0\0"; + + uint8_t version; + 1 - current format + + uint8_t data_block_bits; + log2(data block size) + + uint8_t hash_block_bits; + log2(hash block size) + + uint8_t pad1[1]; + zero padding + + uint16_t salt_size; + big-endian salt size + + uint8_t pad2[2]; + zero padding + + uint32_t data_blocks_hi; + big-endian high 32 bits of the 64-bit number of data blocks + + uint32_t data_blocks_lo; + big-endian low 32 bits of the 64-bit number of data blocks + + uint8_t algorithm[16]; + cryptographic algorithm + + uint8_t salt[384]; + salt (the salt size is specified above) + + uint8_t pad3[88]; + zero padding to 512-byte boundary +} + +Directly following the header (and with sector number padded to the next hash +block boundary) are the hash blocks which are stored a depth at a time +(starting from the root), sorted in order of increasing index. + +Status +====== +V (for Valid) is returned if every check performed so far was valid. +If any check failed, C (for Corruption) is returned. + +Example +======= + +Setup a device: + dmsetup create vroot --table \ + "0 2097152 "\ + "verity 1 /dev/sda1 /dev/sda2 4096 4096 2097152 1 "\ + "4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 "\ + "1234000000000000000000000000000000000000000000000000000000000000" + +A command line tool veritysetup is available to compute or verify +the hash tree or activate the kernel driver. This is available from +the LVM2 upstream repository and may be supplied as a package called +device-mapper-verity-tools: + git://sources.redhat.com/git/lvm2 + http://sourceware.org/git/?p=lvm2.git + http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/verity?cvsroot=lvm2 + +veritysetup -a vroot /dev/sda1 /dev/sda2 \ + 4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 diff --git a/Documentation/devicetree/bindings/arm/atmel-aic.txt b/Documentation/devicetree/bindings/arm/atmel-aic.txt new file mode 100644 index 00000000000..aabca4f8340 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/atmel-aic.txt @@ -0,0 +1,38 @@ +* Advanced Interrupt Controller (AIC) + +Required properties: +- compatible: Should be "atmel,<chip>-aic" +- interrupt-controller: Identifies the node as an interrupt controller. +- interrupt-parent: For single AIC system, it is an empty property. +- #interrupt-cells: The number of cells to define the interrupts. It sould be 2. + The first cell is the IRQ number (aka "Peripheral IDentifier" on datasheet). + The second cell is used to specify flags: + bits[3:0] trigger type and level flags: + 1 = low-to-high edge triggered. + 2 = high-to-low edge triggered. + 4 = active high level-sensitive. + 8 = active low level-sensitive. + Valid combinations are 1, 2, 3, 4, 8. + Default flag for internal sources should be set to 4 (active high). +- reg: Should contain AIC registers location and length + +Examples: + /* + * AIC + */ + aic: interrupt-controller@fffff000 { + compatible = "atmel,at91rm9200-aic"; + interrupt-controller; + interrupt-parent; + #interrupt-cells = <2>; + reg = <0xfffff000 0x200>; + }; + + /* + * An interrupt generating device that is wired to an AIC. + */ + dma: dma-controller@ffffec00 { + compatible = "atmel,at91sam9g45-dma"; + reg = <0xffffec00 0x200>; + interrupts = <21 4>; + }; diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt new file mode 100644 index 00000000000..ecc81e36871 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt @@ -0,0 +1,92 @@ +Atmel AT91 device tree bindings. +================================ + +PIT Timer required properties: +- compatible: Should be "atmel,at91sam9260-pit" +- reg: Should contain registers location and length +- interrupts: Should contain interrupt for the PIT which is the IRQ line + shared across all System Controller members. + +TC/TCLIB Timer required properties: +- compatible: Should be "atmel,<chip>-pit". + <chip> can be "at91rm9200" or "at91sam9x5" +- reg: Should contain registers location and length +- interrupts: Should contain all interrupts for the TC block + Note that you can specify several interrupt cells if the TC + block has one interrupt per channel. + +Examples: + +One interrupt per TC block: + tcb0: timer@fff7c000 { + compatible = "atmel,at91rm9200-tcb"; + reg = <0xfff7c000 0x100>; + interrupts = <18 4>; + }; + +One interrupt per TC channel in a TC block: + tcb1: timer@fffdc000 { + compatible = "atmel,at91rm9200-tcb"; + reg = <0xfffdc000 0x100>; + interrupts = <26 4 27 4 28 4>; + }; + +RSTC Reset Controller required properties: +- compatible: Should be "atmel,<chip>-rstc". + <chip> can be "at91sam9260" or "at91sam9g45" +- reg: Should contain registers location and length + +Example: + + rstc@fffffd00 { + compatible = "atmel,at91sam9260-rstc"; + reg = <0xfffffd00 0x10>; + }; + +RAMC SDRAM/DDR Controller required properties: +- compatible: Should be "atmel,at91sam9260-sdramc", + "atmel,at91sam9g45-ddramc", +- reg: Should contain registers location and length + For at91sam9263 and at91sam9g45 you must specify 2 entries. + +Examples: + + ramc0: ramc@ffffe800 { + compatible = "atmel,at91sam9g45-ddramc"; + reg = <0xffffe800 0x200>; + }; + + ramc0: ramc@ffffe400 { + compatible = "atmel,at91sam9g45-ddramc"; + reg = <0xffffe400 0x200 + 0xffffe600 0x200>; + }; + +SHDWC Shutdown Controller + +required properties: +- compatible: Should be "atmel,<chip>-shdwc". + <chip> can be "at91sam9260", "at91sam9rl" or "at91sam9x5". +- reg: Should contain registers location and length + +optional properties: +- atmel,wakeup-mode: String, operation mode of the wakeup mode. + Supported values are: "none", "high", "low", "any". +- atmel,wakeup-counter: Counter on Wake-up 0 (between 0x0 and 0xf). + +optional at91sam9260 properties: +- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up. + +optional at91sam9rl properties: +- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up. +- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up. + +optional at91sam9x5 properties: +- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up. + +Example: + + rstc@fffffd00 { + compatible = "atmel,at91sam9260-rstc"; + reg = <0xfffffd00 0x10>; + }; diff --git a/Documentation/devicetree/bindings/arm/atmel-pmc.txt b/Documentation/devicetree/bindings/arm/atmel-pmc.txt new file mode 100644 index 00000000000..389bed5056e --- /dev/null +++ b/Documentation/devicetree/bindings/arm/atmel-pmc.txt @@ -0,0 +1,11 @@ +* Power Management Controller (PMC) + +Required properties: +- compatible: Should be "atmel,at91rm9200-pmc" +- reg: Should contain PMC registers location and length + +Examples: + pmc: pmc@fffffc00 { + compatible = "atmel,at91rm9200-pmc"; + reg = <0xfffffc00 0x100>; + }; diff --git a/Documentation/devicetree/bindings/arm/fsl.txt b/Documentation/devicetree/bindings/arm/fsl.txt index 54bdddadf1c..bfbc771a65f 100644 --- a/Documentation/devicetree/bindings/arm/fsl.txt +++ b/Documentation/devicetree/bindings/arm/fsl.txt @@ -28,3 +28,25 @@ Required root node properties: i.MX6 Quad SABRE Lite Board Required root node properties: - compatible = "fsl,imx6q-sabrelite", "fsl,imx6q"; + +Generic i.MX boards +------------------- + +No iomux setup is done for these boards, so this must have been configured +by the bootloader for boards to work with the generic bindings. + +i.MX27 generic board +Required root node properties: + - compatible = "fsl,imx27"; + +i.MX51 generic board +Required root node properties: + - compatible = "fsl,imx51"; + +i.MX53 generic board +Required root node properties: + - compatible = "fsl,imx53"; + +i.MX6q generic board +Required root node properties: + - compatible = "fsl,imx6q"; diff --git a/Documentation/devicetree/bindings/arm/mrvl.txt b/Documentation/devicetree/bindings/arm/mrvl.txt new file mode 100644 index 00000000000..d8de933e9d8 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/mrvl.txt @@ -0,0 +1,6 @@ +Marvell Platforms Device Tree Bindings +---------------------------------------------------- + +PXA168 Aspenite Board +Required root node properties: + - compatible = "mrvl,pxa168-aspenite", "mrvl,pxa168"; diff --git a/Documentation/devicetree/bindings/arm/omap/intc.txt b/Documentation/devicetree/bindings/arm/omap/intc.txt new file mode 100644 index 00000000000..f2583e6ec06 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/omap/intc.txt @@ -0,0 +1,27 @@ +* OMAP Interrupt Controller + +OMAP2/3 are using a TI interrupt controller that can support several +configurable number of interrupts. + +Main node required properties: + +- compatible : should be: + "ti,omap2-intc" +- interrupt-controller : Identifies the node as an interrupt controller +- #interrupt-cells : Specifies the number of cells needed to encode an + interrupt source. The type shall be a <u32> and the value shall be 1. + + The cell contains the interrupt number in the range [0-128]. +- ti,intc-size: Number of interrupts handled by the interrupt controller. +- reg: physical base address and size of the intc registers map. + +Example: + + intc: interrupt-controller@1 { + compatible = "ti,omap2-intc"; + interrupt-controller; + #interrupt-cells = <1>; + ti,intc-size = <96>; + reg = <0x48200000 0x1000>; + }; + diff --git a/Documentation/devicetree/bindings/arm/spear.txt b/Documentation/devicetree/bindings/arm/spear.txt new file mode 100644 index 00000000000..f8e54f09232 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/spear.txt @@ -0,0 +1,8 @@ +ST SPEAr Platforms Device Tree Bindings +--------------------------------------- + +Boards with the ST SPEAr600 SoC shall have the following properties: + +Required root node property: + +compatible = "st,spear600"; diff --git a/Documentation/devicetree/bindings/arm/tegra/emc.txt b/Documentation/devicetree/bindings/arm/tegra/emc.txt new file mode 100644 index 00000000000..09335f8eee0 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/tegra/emc.txt @@ -0,0 +1,100 @@ +Embedded Memory Controller + +Properties: +- name : Should be emc +- #address-cells : Should be 1 +- #size-cells : Should be 0 +- compatible : Should contain "nvidia,tegra20-emc". +- reg : Offset and length of the register set for the device +- nvidia,use-ram-code : If present, the sub-nodes will be addressed + and chosen using the ramcode board selector. If omitted, only one + set of tables can be present and said tables will be used + irrespective of ram-code configuration. + +Child device nodes describe the memory settings for different configurations and clock rates. + +Example: + + emc@7000f400 { + #address-cells = < 1 >; + #size-cells = < 0 >; + compatible = "nvidia,tegra20-emc"; + reg = <0x7000f4000 0x200>; + } + + +Embedded Memory Controller ram-code table + +If the emc node has the nvidia,use-ram-code property present, then the +next level of nodes below the emc table are used to specify which settings +apply for which ram-code settings. + +If the emc node lacks the nvidia,use-ram-code property, this level is omitted +and the tables are stored directly under the emc node (see below). + +Properties: + +- name : Should be emc-tables +- nvidia,ram-code : the binary representation of the ram-code board strappings + for which this node (and children) are valid. + + + +Embedded Memory Controller configuration table + +This is a table containing the EMC register settings for the various +operating speeds of the memory controller. They are always located as +subnodes of the emc controller node. + +There are two ways of specifying which tables to use: + +* The simplest is if there is just one set of tables in the device tree, + and they will always be used (based on which frequency is used). + This is the preferred method, especially when firmware can fill in + this information based on the specific system information and just + pass it on to the kernel. + +* The slightly more complex one is when more than one memory configuration + might exist on the system. The Tegra20 platform handles this during + early boot by selecting one out of possible 4 memory settings based + on a 2-pin "ram code" bootstrap setting on the board. The values of + these strappings can be read through a register in the SoC, and thus + used to select which tables to use. + +Properties: +- name : Should be emc-table +- compatible : Should contain "nvidia,tegra20-emc-table". +- reg : either an opaque enumerator to tell different tables apart, or + the valid frequency for which the table should be used (in kHz). +- clock-frequency : the clock frequency for the EMC at which this + table should be used (in kHz). +- nvidia,emc-registers : a 46 word array of EMC registers to be programmed + for operation at the 'clock-frequency' setting. + The order and contents of the registers are: + RC, RFC, RAS, RP, R2W, W2R, R2P, W2P, RD_RCD, WR_RCD, RRD, REXT, + WDV, QUSE, QRST, QSAFE, RDV, REFRESH, BURST_REFRESH_NUM, PDEX2WR, + PDEX2RD, PCHG2PDEN, ACT2PDEN, AR2PDEN, RW2PDEN, TXSR, TCKE, TFAW, + TRPAB, TCLKSTABLE, TCLKSTOP, TREFBW, QUSE_EXTRA, FBIO_CFG6, ODT_WRITE, + ODT_READ, FBIO_CFG5, CFG_DIG_DLL, DLL_XFORM_DQS, DLL_XFORM_QUSE, + ZCAL_REF_CNT, ZCAL_WAIT_CNT, AUTO_CAL_INTERVAL, CFG_CLKTRIM_0, + CFG_CLKTRIM_1, CFG_CLKTRIM_2 + + emc-table@166000 { + reg = <166000>; + compatible = "nvidia,tegra20-emc-table"; + clock-frequency = < 166000 >; + nvidia,emc-registers = < 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 >; + }; + + emc-table@333000 { + reg = <333000>; + compatible = "nvidia,tegra20-emc-table"; + clock-frequency = < 333000 >; + nvidia,emc-registers = < 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 0 >; + }; diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt new file mode 100644 index 00000000000..b5846e21cc2 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt @@ -0,0 +1,19 @@ +NVIDIA Tegra Power Management Controller (PMC) + +Properties: +- name : Should be pmc +- compatible : Should contain "nvidia,tegra<chip>-pmc". +- reg : Offset and length of the register set for the device +- nvidia,invert-interrupt : If present, inverts the PMU interrupt signal. + The PMU is an external Power Management Unit, whose interrupt output + signal is fed into the PMC. This signal is optionally inverted, and then + fed into the ARM GIC. The PMC is not involved in the detection or + handling of this interrupt signal, merely its inversion. + +Example: + +pmc@7000f400 { + compatible = "nvidia,tegra20-pmc"; + reg = <0x7000e400 0x400>; + nvidia,invert-interrupt; +}; diff --git a/Documentation/devicetree/bindings/arm/twd.txt b/Documentation/devicetree/bindings/arm/twd.txt new file mode 100644 index 00000000000..75b8610939f --- /dev/null +++ b/Documentation/devicetree/bindings/arm/twd.txt @@ -0,0 +1,48 @@ +* ARM Timer Watchdog + +ARM 11MP, Cortex-A5 and Cortex-A9 are often associated with a per-core +Timer-Watchdog (aka TWD), which provides both a per-cpu local timer +and watchdog. + +The TWD is usually attached to a GIC to deliver its two per-processor +interrupts. + +** Timer node required properties: + +- compatible : Should be one of: + "arm,cortex-a9-twd-timer" + "arm,cortex-a5-twd-timer" + "arm,arm11mp-twd-timer" + +- interrupts : One interrupt to each core + +- reg : Specify the base address and the size of the TWD timer + register window. + +Example: + + twd-timer@2c000600 { + compatible = "arm,arm11mp-twd-timer""; + reg = <0x2c000600 0x20>; + interrupts = <1 13 0xf01>; + }; + +** Watchdog node properties: + +- compatible : Should be one of: + "arm,cortex-a9-twd-wdt" + "arm,cortex-a5-twd-wdt" + "arm,arm11mp-twd-wdt" + +- interrupts : One interrupt to each core + +- reg : Specify the base address and the size of the TWD watchdog + register window. + +Example: + + twd-watchdog@2c000620 { + compatible = "arm,arm11mp-twd-wdt"; + reg = <0x2c000620 0x20>; + interrupts = <1 14 0xf01>; + }; diff --git a/Documentation/devicetree/bindings/arm/vexpress.txt b/Documentation/devicetree/bindings/arm/vexpress.txt new file mode 100644 index 00000000000..ec8b50cbb2e --- /dev/null +++ b/Documentation/devicetree/bindings/arm/vexpress.txt @@ -0,0 +1,146 @@ +ARM Versatile Express boards family +----------------------------------- + +ARM's Versatile Express platform consists of a motherboard and one +or more daughterboards (tiles). The motherboard provides a set of +peripherals. Processor and RAM "live" on the tiles. + +The motherboard and each core tile should be described by a separate +Device Tree source file, with the tile's description including +the motherboard file using a /include/ directive. As the motherboard +can be initialized in one of two different configurations ("memory +maps"), care must be taken to include the correct one. + +Required properties in the root node: +- compatible value: + compatible = "arm,vexpress,<model>", "arm,vexpress"; + where <model> is the full tile model name (as used in the tile's + Technical Reference Manual), eg.: + - for Coretile Express A5x2 (V2P-CA5s): + compatible = "arm,vexpress,v2p-ca5s", "arm,vexpress"; + - for Coretile Express A9x4 (V2P-CA9): + compatible = "arm,vexpress,v2p-ca9", "arm,vexpress"; + If a tile comes in several variants or can be used in more then one + configuration, the compatible value should be: + compatible = "arm,vexpress,<model>,<variant>", \ + "arm,vexpress,<model>", "arm,vexpress"; + eg: + - Coretile Express A15x2 (V2P-CA15) with Tech Chip 1: + compatible = "arm,vexpress,v2p-ca15,tc1", \ + "arm,vexpress,v2p-ca15", "arm,vexpress"; + - LogicTile Express 13MG (V2F-2XV6) running Cortex-A7 (3 cores) SMM: + compatible = "arm,vexpress,v2f-2xv6,ca7x3", \ + "arm,vexpress,v2f-2xv6", "arm,vexpress"; + +Optional properties in the root node: +- tile model name (use name from the tile's Technical Reference + Manual, eg. "V2P-CA5s") + model = "<model>"; +- tile's HBI number (unique ARM's board model ID, visible on the + PCB's silkscreen) in hexadecimal transcription: + arm,hbi = <0xhbi> + eg: + - for Coretile Express A5x2 (V2P-CA5s) HBI-0191: + arm,hbi = <0x191>; + - Coretile Express A9x4 (V2P-CA9) HBI-0225: + arm,hbi = <0x225>; + +Top-level standard "cpus" node is required. It must contain a node +with device_type = "cpu" property for every available core, eg.: + + cpus { + #address-cells = <1>; + #size-cells = <0>; + + cpu@0 { + device_type = "cpu"; + compatible = "arm,cortex-a5"; + reg = <0>; + }; + }; + +The motherboard description file provides a single "motherboard" node +using 2 address cells corresponding to the Static Memory Bus used +between the motherboard and the tile. The first cell defines the Chip +Select (CS) line number, the second cell address offset within the CS. +All interrupt lines between the motherboard and the tile are active +high and are described using single cell. + +Optional properties of the "motherboard" node: +- motherboard's memory map variant: + arm,v2m-memory-map = "<name>"; + where name is one of: + - "rs1" - for RS1 map (i.a. peripherals on CS3); this map is also + referred to as "ARM Cortex-A Series memory map": + arm,v2m-memory-map = "rs1"; + When this property is missing, the motherboard is using the original + memory map (also known as the "Legacy memory map", primarily used + with the original CoreTile Express A9x4) with peripherals on CS7. + +Motherboard .dtsi files provide a set of labelled peripherals that +can be used to obtain required phandle in the tile's "aliases" node: +- UARTs, note that the numbers correspond to the physical connectors + on the motherboard's back panel: + v2m_serial0, v2m_serial1, v2m_serial2 and v2m_serial3 +- I2C controllers: + v2m_i2c_dvi and v2m_i2c_pcie +- SP804 timers: + v2m_timer01 and v2m_timer23 + +Current Linux implementation requires a "arm,v2m_timer" alias +pointing at one of the motherboard's SP804 timers, if it is to be +used as the system timer. This alias should be defined in the +motherboard files. + +The tile description must define "ranges", "interrupt-map-mask" and +"interrupt-map" properties to translate the motherboard's address +and interrupt space into one used by the tile's processor. + +Abbreviated example: + +/dts-v1/; + +/ { + model = "V2P-CA5s"; + arm,hbi = <0x225>; + compatible = "arm,vexpress-v2p-ca5s", "arm,vexpress"; + interrupt-parent = <&gic>; + #address-cells = <1>; + #size-cells = <1>; + + chosen { }; + + aliases { + serial0 = &v2m_serial0; + }; + + cpus { + #address-cells = <1>; + #size-cells = <0>; + + cpu@0 { + device_type = "cpu"; + compatible = "arm,cortex-a5"; + reg = <0>; + }; + }; + + gic: interrupt-controller@2c001000 { + compatible = "arm,cortex-a9-gic"; + #interrupt-cells = <3>; + #address-cells = <0>; + interrupt-controller; + reg = <0x2c001000 0x1000>, + <0x2c000100 0x100>; + }; + + motherboard { + /* CS0 is visible at 0x08000000 */ + ranges = <0 0 0x08000000 0x04000000>; + interrupt-map-mask = <0 0 63>; + /* Active high IRQ 0 is connected to GIC's SPI0 */ + interrupt-map = <0 0 0 &gic 0 0 4>; + }; +}; + +/include/ "vexpress-v2m-rs1.dtsi" diff --git a/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt b/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt new file mode 100644 index 00000000000..90fa7da525b --- /dev/null +++ b/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt @@ -0,0 +1,30 @@ +* NVIDIA Tegra APB DMA controller + +Required properties: +- compatible: Should be "nvidia,<chip>-apbdma" +- reg: Should contain DMA registers location and length. This shuld include + all of the per-channel registers. +- interrupts: Should contain all of the per-channel DMA interrupts. + +Examples: + +apbdma: dma@6000a000 { + compatible = "nvidia,tegra20-apbdma"; + reg = <0x6000a000 0x1200>; + interrupts = < 0 136 0x04 + 0 137 0x04 + 0 138 0x04 + 0 139 0x04 + 0 140 0x04 + 0 141 0x04 + 0 142 0x04 + 0 143 0x04 + 0 144 0x04 + 0 145 0x04 + 0 146 0x04 + 0 147 0x04 + 0 148 0x04 + 0 149 0x04 + 0 150 0x04 + 0 151 0x04 >; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt new file mode 100644 index 00000000000..66efc804806 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt @@ -0,0 +1,20 @@ +* Atmel GPIO controller (PIO) + +Required properties: +- compatible: "atmel,<chip>-gpio", where <chip> is at91rm9200 or at91sam9x5. +- reg: Should contain GPIO controller registers location and length +- interrupts: Should be the port interrupt shared by all the pins. +- #gpio-cells: Should be two. The first cell is the pin number and + the second cell is used to specify optional parameters (currently + unused). +- gpio-controller: Marks the device node as a GPIO controller. + +Example: + pioA: gpio@fffff200 { + compatible = "atmel,at91rm9200-gpio"; + reg = <0xfffff200 0x100>; + interrupts = <2 4>; + #gpio-cells = <2>; + gpio-controller; + }; + diff --git a/Documentation/devicetree/bindings/gpio/gpio_i2c.txt b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt new file mode 100644 index 00000000000..4f8ec947c6b --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio_i2c.txt @@ -0,0 +1,32 @@ +Device-Tree bindings for i2c gpio driver + +Required properties: + - compatible = "i2c-gpio"; + - gpios: sda and scl gpio + + +Optional properties: + - i2c-gpio,sda-open-drain: sda as open drain + - i2c-gpio,scl-open-drain: scl as open drain + - i2c-gpio,scl-output-only: scl as output only + - i2c-gpio,delay-us: delay between GPIO operations (may depend on each platform) + - i2c-gpio,timeout-ms: timeout to get data + +Example nodes: + +i2c@0 { + compatible = "i2c-gpio"; + gpios = <&pioA 23 0 /* sda */ + &pioA 24 0 /* scl */ + >; + i2c-gpio,sda-open-drain; + i2c-gpio,scl-open-drain; + i2c-gpio,delay-us = <2>; /* ~100 kHz */ + #address-cells = <1>; + #size-cells = <0>; + + rv3029c2@56 { + compatible = "rv3029c2"; + reg = <0x56>; + }; +}; diff --git a/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt b/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt index eb4b530d64e..023c9526e5f 100644 --- a/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt +++ b/Documentation/devicetree/bindings/gpio/gpio_nvidia.txt @@ -1,8 +1,40 @@ -NVIDIA Tegra 2 GPIO controller +NVIDIA Tegra GPIO controller Required properties: -- compatible : "nvidia,tegra20-gpio" +- compatible : "nvidia,tegra<chip>-gpio" +- reg : Physical base address and length of the controller's registers. +- interrupts : The interrupt outputs from the controller. For Tegra20, + there should be 7 interrupts specified, and for Tegra30, there should + be 8 interrupts specified. - #gpio-cells : Should be two. The first cell is the pin number and the second cell is used to specify optional parameters: - bit 0 specifies polarity (0 for normal, 1 for inverted) - gpio-controller : Marks the device node as a GPIO controller. +- #interrupt-cells : Should be 2. + The first cell is the GPIO number. + The second cell is used to specify flags: + bits[3:0] trigger type and level flags: + 1 = low-to-high edge triggered. + 2 = high-to-low edge triggered. + 4 = active high level-sensitive. + 8 = active low level-sensitive. + Valid combinations are 1, 2, 3, 4, 8. +- interrupt-controller : Marks the device node as an interrupt controller. + +Example: + +gpio: gpio@6000d000 { + compatible = "nvidia,tegra20-gpio"; + reg = < 0x6000d000 0x1000 >; + interrupts = < 0 32 0x04 + 0 33 0x04 + 0 34 0x04 + 0 35 0x04 + 0 55 0x04 + 0 87 0x04 + 0 89 0x04 >; + #gpio-cells = <2>; + gpio-controller; + #interrupt-cells = <2>; + interrupt-controller; +}; diff --git a/Documentation/devicetree/bindings/gpio/mrvl-gpio.txt b/Documentation/devicetree/bindings/gpio/mrvl-gpio.txt new file mode 100644 index 00000000000..1e34cfe5ebe --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/mrvl-gpio.txt @@ -0,0 +1,23 @@ +* Marvell PXA GPIO controller + +Required properties: +- compatible : Should be "mrvl,pxa-gpio" or "mrvl,mmp-gpio" +- reg : Address and length of the register set for the device +- interrupts : Should be the port interrupt shared by all gpio pins, if +- interrupt-name : Should be the name of irq resource. + one number. +- gpio-controller : Marks the device node as a gpio controller. +- #gpio-cells : Should be one. It is the pin number. + +Example: + + gpio: gpio@d4019000 { + compatible = "mrvl,mmp-gpio", "mrvl,pxa-gpio"; + reg = <0xd4019000 0x1000>; + interrupts = <49>, <17>, <18>; + interrupt-name = "gpio_mux", "gpio0", "gpio1"; + gpio-controller; + #gpio-cells = <1>; + interrupt-controller; + #interrupt-cells = <1>; + }; diff --git a/Documentation/devicetree/bindings/i2c/mrvl-i2c.txt b/Documentation/devicetree/bindings/i2c/mrvl-i2c.txt new file mode 100644 index 00000000000..071eb3caae9 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/mrvl-i2c.txt @@ -0,0 +1,37 @@ +* I2C + +Required properties : + + - reg : Offset and length of the register set for the device + - compatible : should be "mrvl,mmp-twsi" where CHIP is the name of a + compatible processor, e.g. pxa168, pxa910, mmp2, mmp3. + For the pxa2xx/pxa3xx, an additional node "mrvl,pxa-i2c" is required + as shown in the example below. + +Recommended properties : + + - interrupts : <a b> where a is the interrupt number and b is a + field that represents an encoding of the sense and level + information for the interrupt. This should be encoded based on + the information in section 2) depending on the type of interrupt + controller you have. + - interrupt-parent : the phandle for the interrupt controller that + services interrupts for this device. + - mrvl,i2c-polling : Disable interrupt of i2c controller. Polling + status register of i2c controller instead. + - mrvl,i2c-fast-mode : Enable fast mode of i2c controller. + +Examples: + twsi1: i2c@d4011000 { + compatible = "mrvl,mmp-twsi", "mrvl,pxa-i2c"; + reg = <0xd4011000 0x1000>; + interrupts = <7>; + mrvl,i2c-fast-mode; + }; + + twsi2: i2c@d4025000 { + compatible = "mrvl,mmp-twsi", "mrvl,pxa-i2c"; + reg = <0xd4025000 0x1000>; + interrupts = <58>; + }; + diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt new file mode 100644 index 00000000000..5903ecf6e89 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt @@ -0,0 +1,41 @@ +Atmel NAND flash + +Required properties: +- compatible : "atmel,at91rm9200-nand". +- reg : should specify localbus address and size used for the chip, + and if availlable the ECC. +- atmel,nand-addr-offset : offset for the address latch. +- atmel,nand-cmd-offset : offset for the command latch. +- #address-cells, #size-cells : Must be present if the device has sub-nodes + representing partitions. + +- gpios : specifies the gpio pins to control the NAND device. detect is an + optional gpio and may be set to 0 if not present. + +Optional properties: +- nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default. + Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first", + "soft_bch". +- nand-bus-width : 8 or 16 bus width if not present 8 +- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false + +Examples: +nand0: nand@40000000,0 { + compatible = "atmel,at91rm9200-nand"; + #address-cells = <1>; + #size-cells = <1>; + reg = <0x40000000 0x10000000 + 0xffffe800 0x200 + >; + atmel,nand-addr-offset = <21>; + atmel,nand-cmd-offset = <22>; + nand-on-flash-bbt; + nand-ecc-mode = "soft"; + gpios = <&pioC 13 0 + &pioC 14 0 + 0 + >; + partition@0 { + ... + }; +}; diff --git a/Documentation/devicetree/bindings/mtd/nand.txt b/Documentation/devicetree/bindings/mtd/nand.txt new file mode 100644 index 00000000000..03855c8c492 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/nand.txt @@ -0,0 +1,7 @@ +* MTD generic binding + +- nand-ecc-mode : String, operation mode of the NAND ecc mode. + Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first", + "soft_bch". +- nand-bus-width : 8 or 16 bus width if not present 8 +- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false diff --git a/Documentation/devicetree/bindings/rtc/sa1100-rtc.txt b/Documentation/devicetree/bindings/rtc/sa1100-rtc.txt new file mode 100644 index 00000000000..0cda19ad485 --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/sa1100-rtc.txt @@ -0,0 +1,17 @@ +* Marvell Real Time Clock controller + +Required properties: +- compatible: should be "mrvl,sa1100-rtc" +- reg: physical base address of the controller and length of memory mapped + region. +- interrupts: Should be two. The first interrupt number is the rtc alarm + interrupt and the second interrupt number is the rtc hz interrupt. +- interrupt-names: Assign name of irq resource. + +Example: + rtc: rtc@d4010000 { + compatible = "mrvl,mmp-rtc"; + reg = <0xd4010000 0x1000>; + interrupts = <5>, <6>; + interrupt-name = "rtc 1Hz", "rtc alarm"; + }; diff --git a/Documentation/devicetree/bindings/serial/mrvl-serial.txt b/Documentation/devicetree/bindings/serial/mrvl-serial.txt new file mode 100644 index 00000000000..d744340de88 --- /dev/null +++ b/Documentation/devicetree/bindings/serial/mrvl-serial.txt @@ -0,0 +1,4 @@ +PXA UART controller + +Required properties: +- compatible : should be "mrvl,mmp-uart" or "mrvl,pxa-uart". diff --git a/Documentation/devicetree/bindings/usb/atmel-usb.txt b/Documentation/devicetree/bindings/usb/atmel-usb.txt new file mode 100644 index 00000000000..60bd2150a3e --- /dev/null +++ b/Documentation/devicetree/bindings/usb/atmel-usb.txt @@ -0,0 +1,49 @@ +Atmel SOC USB controllers + +OHCI + +Required properties: + - compatible: Should be "atmel,at91rm9200-ohci" for USB controllers + used in host mode. + - num-ports: Number of ports. + - atmel,vbus-gpio: If present, specifies a gpio that needs to be + activated for the bus to be powered. + - atmel,oc-gpio: If present, specifies a gpio that needs to be + activated for the overcurrent detection. + +usb0: ohci@00500000 { + compatible = "atmel,at91rm9200-ohci", "usb-ohci"; + reg = <0x00500000 0x100000>; + interrupts = <20 4>; + num-ports = <2>; +}; + +EHCI + +Required properties: + - compatible: Should be "atmel,at91sam9g45-ehci" for USB controllers + used in host mode. + +usb1: ehci@00800000 { + compatible = "atmel,at91sam9g45-ehci", "usb-ehci"; + reg = <0x00800000 0x100000>; + interrupts = <22 4>; +}; + +AT91 USB device controller + +Required properties: + - compatible: Should be "atmel,at91rm9200-udc" + - reg: Address and length of the register set for the device + - interrupts: Should contain macb interrupt + +Optional properties: + - atmel,vbus-gpio: If present, specifies a gpio that needs to be + activated for the bus to be powered. + +usb1: gadget@fffa4000 { + compatible = "atmel,at91rm9200-udc"; + reg = <0xfffa4000 0x4000>; + interrupts = <10 4>; + atmel,vbus-gpio = <&pioC 5 0>; +}; diff --git a/Documentation/devicetree/bindings/usb/tegra-usb.txt b/Documentation/devicetree/bindings/usb/tegra-usb.txt index 035d63d5646..007005ddbe1 100644 --- a/Documentation/devicetree/bindings/usb/tegra-usb.txt +++ b/Documentation/devicetree/bindings/usb/tegra-usb.txt @@ -11,3 +11,16 @@ Required properties : - phy_type : Should be one of "ulpi" or "utmi". - nvidia,vbus-gpio : If present, specifies a gpio that needs to be activated for the bus to be powered. + +Optional properties: + - dr_mode : dual role mode. Indicates the working mode for + nvidia,tegra20-ehci compatible controllers. Can be "host", "peripheral", + or "otg". Default to "host" if not defined for backward compatibility. + host means this is a host controller + peripheral means it is device controller + otg means it can operate as either ("on the go") + - nvidia,has-legacy-mode : boolean indicates whether this controller can + operate in legacy mode (as APX 2500 / 2600). In legacy mode some + registers are accessed through the APB_MISC base address instead of + the USB controller. Since this is a legacy issue it probably does not + warrant a compatible string of its own. diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index 4bfd982f808..0cad4803ffa 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -513,20 +513,6 @@ Who: Bjorn Helgaas <bhelgaas@google.com> ---------------------------- -What: The CAP9 SoC family will be removed -When: 3.4 -Files: arch/arm/mach-at91/at91cap9.c - arch/arm/mach-at91/at91cap9_devices.c - arch/arm/mach-at91/include/mach/at91cap9.h - arch/arm/mach-at91/include/mach/at91cap9_matrix.h - arch/arm/mach-at91/include/mach/at91cap9_ddrsdr.h - arch/arm/mach-at91/board-cap9adk.c -Why: The code is not actively maintained and platforms are now hard to find. -Who: Nicolas Ferre <nicolas.ferre@atmel.com> - Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> - ----------------------------- - What: Low Performance USB Block driver ("CONFIG_BLK_DEV_UB") When: 3.6 Why: This driver provides support for USB storage devices like "USB diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 8c10bf375c7..1b7f9acbcbb 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -144,9 +144,6 @@ journal_async_commit Commit block can be written to disk without waiting mount the device. This will enable 'journal_checksum' internally. -journal=update Update the ext4 file system's journal to the current - format. - journal_dev=devnum When the external journal device's major/minor numbers have changed, this option allows the user to specify the new journal location. The journal device is @@ -356,11 +353,6 @@ nouid32 Disables 32-bit UIDs and GIDs. This is for interoperability with older kernels which only store and expect 16-bit values. -resize Allows to resize filesystem to the end of the last - existing block group, further resize has to be done - with resize2fs either online, or offline. It can be - used only with conjunction with remount. - block_validity This options allows to enables/disables the in-kernel noblock_validity facility for tracking filesystem metadata blocks within internal data structures. This allows multi- diff --git a/Documentation/remoteproc.txt b/Documentation/remoteproc.txt new file mode 100644 index 00000000000..70a048cd3fa --- /dev/null +++ b/Documentation/remoteproc.txt @@ -0,0 +1,322 @@ +Remote Processor Framework + +1. Introduction + +Modern SoCs typically have heterogeneous remote processor devices in asymmetric +multiprocessing (AMP) configurations, which may be running different instances +of operating system, whether it's Linux or any other flavor of real-time OS. + +OMAP4, for example, has dual Cortex-A9, dual Cortex-M3 and a C64x+ DSP. +In a typical configuration, the dual cortex-A9 is running Linux in a SMP +configuration, and each of the other three cores (two M3 cores and a DSP) +is running its own instance of RTOS in an AMP configuration. + +The remoteproc framework allows different platforms/architectures to +control (power on, load firmware, power off) those remote processors while +abstracting the hardware differences, so the entire driver doesn't need to be +duplicated. In addition, this framework also adds rpmsg virtio devices +for remote processors that supports this kind of communication. This way, +platform-specific remoteproc drivers only need to provide a few low-level +handlers, and then all rpmsg drivers will then just work +(for more information about the virtio-based rpmsg bus and its drivers, +please read Documentation/rpmsg.txt). +Registration of other types of virtio devices is now also possible. Firmwares +just need to publish what kind of virtio devices do they support, and then +remoteproc will add those devices. This makes it possible to reuse the +existing virtio drivers with remote processor backends at a minimal development +cost. + +2. User API + + int rproc_boot(struct rproc *rproc) + - Boot a remote processor (i.e. load its firmware, power it on, ...). + If the remote processor is already powered on, this function immediately + returns (successfully). + Returns 0 on success, and an appropriate error value otherwise. + Note: to use this function you should already have a valid rproc + handle. There are several ways to achieve that cleanly (devres, pdata, + the way remoteproc_rpmsg.c does this, or, if this becomes prevalent, we + might also consider using dev_archdata for this). See also + rproc_get_by_name() below. + + void rproc_shutdown(struct rproc *rproc) + - Power off a remote processor (previously booted with rproc_boot()). + In case @rproc is still being used by an additional user(s), then + this function will just decrement the power refcount and exit, + without really powering off the device. + Every call to rproc_boot() must (eventually) be accompanied by a call + to rproc_shutdown(). Calling rproc_shutdown() redundantly is a bug. + Notes: + - we're not decrementing the rproc's refcount, only the power refcount. + which means that the @rproc handle stays valid even after + rproc_shutdown() returns, and users can still use it with a subsequent + rproc_boot(), if needed. + - don't call rproc_shutdown() to unroll rproc_get_by_name(), exactly + because rproc_shutdown() _does not_ decrement the refcount of @rproc. + To decrement the refcount of @rproc, use rproc_put() (but _only_ if + you acquired @rproc using rproc_get_by_name()). + + struct rproc *rproc_get_by_name(const char *name) + - Find an rproc handle using the remote processor's name, and then + boot it. If it's already powered on, then just immediately return + (successfully). Returns the rproc handle on success, and NULL on failure. + This function increments the remote processor's refcount, so always + use rproc_put() to decrement it back once rproc isn't needed anymore. + Note: currently rproc_get_by_name() and rproc_put() are not used anymore + by the rpmsg bus and its drivers. We need to scrutinize the use cases + that still need them, and see if we can migrate them to use the non + name-based boot/shutdown interface. + + void rproc_put(struct rproc *rproc) + - Decrement @rproc's power refcount and shut it down if it reaches zero + (essentially by just calling rproc_shutdown), and then decrement @rproc's + validity refcount too. + After this function returns, @rproc may _not_ be used anymore, and its + handle should be considered invalid. + This function should be called _iff_ the @rproc handle was grabbed by + calling rproc_get_by_name(). + +3. Typical usage + +#include <linux/remoteproc.h> + +/* in case we were given a valid 'rproc' handle */ +int dummy_rproc_example(struct rproc *my_rproc) +{ + int ret; + + /* let's power on and boot our remote processor */ + ret = rproc_boot(my_rproc); + if (ret) { + /* + * something went wrong. handle it and leave. + */ + } + + /* + * our remote processor is now powered on... give it some work + */ + + /* let's shut it down now */ + rproc_shutdown(my_rproc); +} + +4. API for implementors + + struct rproc *rproc_alloc(struct device *dev, const char *name, + const struct rproc_ops *ops, + const char *firmware, int len) + - Allocate a new remote processor handle, but don't register + it yet. Required parameters are the underlying device, the + name of this remote processor, platform-specific ops handlers, + the name of the firmware to boot this rproc with, and the + length of private data needed by the allocating rproc driver (in bytes). + + This function should be used by rproc implementations during + initialization of the remote processor. + After creating an rproc handle using this function, and when ready, + implementations should then call rproc_register() to complete + the registration of the remote processor. + On success, the new rproc is returned, and on failure, NULL. + + Note: _never_ directly deallocate @rproc, even if it was not registered + yet. Instead, if you just need to unroll rproc_alloc(), use rproc_free(). + + void rproc_free(struct rproc *rproc) + - Free an rproc handle that was allocated by rproc_alloc. + This function should _only_ be used if @rproc was only allocated, + but not registered yet. + If @rproc was already successfully registered (by calling + rproc_register()), then use rproc_unregister() instead. + + int rproc_register(struct rproc *rproc) + - Register @rproc with the remoteproc framework, after it has been + allocated with rproc_alloc(). + This is called by the platform-specific rproc implementation, whenever + a new remote processor device is probed. + Returns 0 on success and an appropriate error code otherwise. + Note: this function initiates an asynchronous firmware loading + context, which will look for virtio devices supported by the rproc's + firmware. + If found, those virtio devices will be created and added, so as a result + of registering this remote processor, additional virtio drivers might get + probed. + + int rproc_unregister(struct rproc *rproc) + - Unregister a remote processor, and decrement its refcount. + If its refcount drops to zero, then @rproc will be freed. If not, + it will be freed later once the last reference is dropped. + + This function should be called when the platform specific rproc + implementation decides to remove the rproc device. it should + _only_ be called if a previous invocation of rproc_register() + has completed successfully. + + After rproc_unregister() returns, @rproc is _not_ valid anymore and + it shouldn't be used. More specifically, don't call rproc_free() + or try to directly free @rproc after rproc_unregister() returns; + none of these are needed, and calling them is a bug. + + Returns 0 on success and -EINVAL if @rproc isn't valid. + +5. Implementation callbacks + +These callbacks should be provided by platform-specific remoteproc +drivers: + +/** + * struct rproc_ops - platform-specific device handlers + * @start: power on the device and boot it + * @stop: power off the device + * @kick: kick a virtqueue (virtqueue id given as a parameter) + */ +struct rproc_ops { + int (*start)(struct rproc *rproc); + int (*stop)(struct rproc *rproc); + void (*kick)(struct rproc *rproc, int vqid); +}; + +Every remoteproc implementation should at least provide the ->start and ->stop +handlers. If rpmsg/virtio functionality is also desired, then the ->kick handler +should be provided as well. + +The ->start() handler takes an rproc handle and should then power on the +device and boot it (use rproc->priv to access platform-specific private data). +The boot address, in case needed, can be found in rproc->bootaddr (remoteproc +core puts there the ELF entry point). +On success, 0 should be returned, and on failure, an appropriate error code. + +The ->stop() handler takes an rproc handle and powers the device down. +On success, 0 is returned, and on failure, an appropriate error code. + +The ->kick() handler takes an rproc handle, and an index of a virtqueue +where new message was placed in. Implementations should interrupt the remote +processor and let it know it has pending messages. Notifying remote processors +the exact virtqueue index to look in is optional: it is easy (and not +too expensive) to go through the existing virtqueues and look for new buffers +in the used rings. + +6. Binary Firmware Structure + +At this point remoteproc only supports ELF32 firmware binaries. However, +it is quite expected that other platforms/devices which we'd want to +support with this framework will be based on different binary formats. + +When those use cases show up, we will have to decouple the binary format +from the framework core, so we can support several binary formats without +duplicating common code. + +When the firmware is parsed, its various segments are loaded to memory +according to the specified device address (might be a physical address +if the remote processor is accessing memory directly). + +In addition to the standard ELF segments, most remote processors would +also include a special section which we call "the resource table". + +The resource table contains system resources that the remote processor +requires before it should be powered on, such as allocation of physically +contiguous memory, or iommu mapping of certain on-chip peripherals. +Remotecore will only power up the device after all the resource table's +requirement are met. + +In addition to system resources, the resource table may also contain +resource entries that publish the existence of supported features +or configurations by the remote processor, such as trace buffers and +supported virtio devices (and their configurations). + +The resource table begins with this header: + +/** + * struct resource_table - firmware resource table header + * @ver: version number + * @num: number of resource entries + * @reserved: reserved (must be zero) + * @offset: array of offsets pointing at the various resource entries + * + * The header of the resource table, as expressed by this structure, + * contains a version number (should we need to change this format in the + * future), the number of available resource entries, and their offsets + * in the table. + */ +struct resource_table { + u32 ver; + u32 num; + u32 reserved[2]; + u32 offset[0]; +} __packed; + +Immediately following this header are the resource entries themselves, +each of which begins with the following resource entry header: + +/** + * struct fw_rsc_hdr - firmware resource entry header + * @type: resource type + * @data: resource data + * + * Every resource entry begins with a 'struct fw_rsc_hdr' header providing + * its @type. The content of the entry itself will immediately follow + * this header, and it should be parsed according to the resource type. + */ +struct fw_rsc_hdr { + u32 type; + u8 data[0]; +} __packed; + +Some resources entries are mere announcements, where the host is informed +of specific remoteproc configuration. Other entries require the host to +do something (e.g. allocate a system resource). Sometimes a negotiation +is expected, where the firmware requests a resource, and once allocated, +the host should provide back its details (e.g. address of an allocated +memory region). + +Here are the various resource types that are currently supported: + +/** + * enum fw_resource_type - types of resource entries + * + * @RSC_CARVEOUT: request for allocation of a physically contiguous + * memory region. + * @RSC_DEVMEM: request to iommu_map a memory-based peripheral. + * @RSC_TRACE: announces the availability of a trace buffer into which + * the remote processor will be writing logs. + * @RSC_VDEV: declare support for a virtio device, and serve as its + * virtio header. + * @RSC_LAST: just keep this one at the end + * + * Please note that these values are used as indices to the rproc_handle_rsc + * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to + * check the validity of an index before the lookup table is accessed, so + * please update it as needed. + */ +enum fw_resource_type { + RSC_CARVEOUT = 0, + RSC_DEVMEM = 1, + RSC_TRACE = 2, + RSC_VDEV = 3, + RSC_LAST = 4, +}; + +For more details regarding a specific resource type, please see its +dedicated structure in include/linux/remoteproc.h. + +We also expect that platform-specific resource entries will show up +at some point. When that happens, we could easily add a new RSC_PLATFORM +type, and hand those resources to the platform-specific rproc driver to handle. + +7. Virtio and remoteproc + +The firmware should provide remoteproc information about virtio devices +that it supports, and their configurations: a RSC_VDEV resource entry +should specify the virtio device id (as in virtio_ids.h), virtio features, +virtio config space, vrings information, etc. + +When a new remote processor is registered, the remoteproc framework +will look for its resource table and will register the virtio devices +it supports. A firmware may support any number of virtio devices, and +of any type (a single remote processor can also easily support several +rpmsg virtio devices this way, if desired). + +Of course, RSC_VDEV resource entries are only good enough for static +allocation of virtio devices. Dynamic allocations will also be made possible +using the rpmsg bus (similar to how we already do dynamic allocations of +rpmsg channels; read more about it in rpmsg.txt). diff --git a/Documentation/rpmsg.txt b/Documentation/rpmsg.txt new file mode 100644 index 00000000000..409d9f964c5 --- /dev/null +++ b/Documentation/rpmsg.txt @@ -0,0 +1,293 @@ +Remote Processor Messaging (rpmsg) Framework + +Note: this document describes the rpmsg bus and how to write rpmsg drivers. +To learn how to add rpmsg support for new platforms, check out remoteproc.txt +(also a resident of Documentation/). + +1. Introduction + +Modern SoCs typically employ heterogeneous remote processor devices in +asymmetric multiprocessing (AMP) configurations, which may be running +different instances of operating system, whether it's Linux or any other +flavor of real-time OS. + +OMAP4, for example, has dual Cortex-A9, dual Cortex-M3 and a C64x+ DSP. +Typically, the dual cortex-A9 is running Linux in a SMP configuration, +and each of the other three cores (two M3 cores and a DSP) is running +its own instance of RTOS in an AMP configuration. + +Typically AMP remote processors employ dedicated DSP codecs and multimedia +hardware accelerators, and therefore are often used to offload CPU-intensive +multimedia tasks from the main application processor. + +These remote processors could also be used to control latency-sensitive +sensors, drive random hardware blocks, or just perform background tasks +while the main CPU is idling. + +Users of those remote processors can either be userland apps (e.g. multimedia +frameworks talking with remote OMX components) or kernel drivers (controlling +hardware accessible only by the remote processor, reserving kernel-controlled +resources on behalf of the remote processor, etc..). + +Rpmsg is a virtio-based messaging bus that allows kernel drivers to communicate +with remote processors available on the system. In turn, drivers could then +expose appropriate user space interfaces, if needed. + +When writing a driver that exposes rpmsg communication to userland, please +keep in mind that remote processors might have direct access to the +system's physical memory and other sensitive hardware resources (e.g. on +OMAP4, remote cores and hardware accelerators may have direct access to the +physical memory, gpio banks, dma controllers, i2c bus, gptimers, mailbox +devices, hwspinlocks, etc..). Moreover, those remote processors might be +running RTOS where every task can access the entire memory/devices exposed +to the processor. To minimize the risks of rogue (or buggy) userland code +exploiting remote bugs, and by that taking over the system, it is often +desired to limit userland to specific rpmsg channels (see definition below) +it can send messages on, and if possible, minimize how much control +it has over the content of the messages. + +Every rpmsg device is a communication channel with a remote processor (thus +rpmsg devices are called channels). Channels are identified by a textual name +and have a local ("source") rpmsg address, and remote ("destination") rpmsg +address. + +When a driver starts listening on a channel, its rx callback is bound with +a unique rpmsg local address (a 32-bit integer). This way when inbound messages +arrive, the rpmsg core dispatches them to the appropriate driver according +to their destination address (this is done by invoking the driver's rx handler +with the payload of the inbound message). + + +2. User API + + int rpmsg_send(struct rpmsg_channel *rpdev, void *data, int len); + - sends a message across to the remote processor on a given channel. + The caller should specify the channel, the data it wants to send, + and its length (in bytes). The message will be sent on the specified + channel, i.e. its source and destination address fields will be + set to the channel's src and dst addresses. + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_sendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst); + - sends a message across to the remote processor on a given channel, + to a destination address provided by the caller. + The caller should specify the channel, the data it wants to send, + its length (in bytes), and an explicit destination address. + The message will then be sent to the remote processor to which the + channel belongs, using the channel's src address, and the user-provided + dst address (thus the channel's dst address will be ignored). + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_send_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len); + - sends a message across to the remote processor, using the src and dst + addresses provided by the user. + The caller should specify the channel, the data it wants to send, + its length (in bytes), and explicit source and destination addresses. + The message will then be sent to the remote processor to which the + channel belongs, but the channel's src and dst addresses will be + ignored (and the user-provided addresses will be used instead). + + In case there are no TX buffers available, the function will block until + one becomes available (i.e. until the remote processor consumes + a tx buffer and puts it back on virtio's used descriptor ring), + or a timeout of 15 seconds elapses. When the latter happens, + -ERESTARTSYS is returned. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysend(struct rpmsg_channel *rpdev, void *data, int len); + - sends a message across to the remote processor on a given channel. + The caller should specify the channel, the data it wants to send, + and its length (in bytes). The message will be sent on the specified + channel, i.e. its source and destination address fields will be + set to the channel's src and dst addresses. + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysendto(struct rpmsg_channel *rpdev, void *data, int len, u32 dst) + - sends a message across to the remote processor on a given channel, + to a destination address provided by the user. + The user should specify the channel, the data it wants to send, + its length (in bytes), and an explicit destination address. + The message will then be sent to the remote processor to which the + channel belongs, using the channel's src address, and the user-provided + dst address (thus the channel's dst address will be ignored). + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + int rpmsg_trysend_offchannel(struct rpmsg_channel *rpdev, u32 src, u32 dst, + void *data, int len); + - sends a message across to the remote processor, using source and + destination addresses provided by the user. + The user should specify the channel, the data it wants to send, + its length (in bytes), and explicit source and destination addresses. + The message will then be sent to the remote processor to which the + channel belongs, but the channel's src and dst addresses will be + ignored (and the user-provided addresses will be used instead). + + In case there are no TX buffers available, the function will immediately + return -ENOMEM without waiting until one becomes available. + The function can only be called from a process context (for now). + Returns 0 on success and an appropriate error value on failure. + + struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_channel *rpdev, + void (*cb)(struct rpmsg_channel *, void *, int, void *, u32), + void *priv, u32 addr); + - every rpmsg address in the system is bound to an rx callback (so when + inbound messages arrive, they are dispatched by the rpmsg bus using the + appropriate callback handler) by means of an rpmsg_endpoint struct. + + This function allows drivers to create such an endpoint, and by that, + bind a callback, and possibly some private data too, to an rpmsg address + (either one that is known in advance, or one that will be dynamically + assigned for them). + + Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint + is already created for them when they are probed by the rpmsg bus + (using the rx callback they provide when they registered to the rpmsg bus). + + So things should just work for simple drivers: they already have an + endpoint, their rx callback is bound to their rpmsg address, and when + relevant inbound messages arrive (i.e. messages which their dst address + equals to the src address of their rpmsg channel), the driver's handler + is invoked to process it. + + That said, more complicated drivers might do need to allocate + additional rpmsg addresses, and bind them to different rx callbacks. + To accomplish that, those drivers need to call this function. + Drivers should provide their channel (so the new endpoint would bind + to the same remote processor their channel belongs to), an rx callback + function, an optional private data (which is provided back when the + rx callback is invoked), and an address they want to bind with the + callback. If addr is RPMSG_ADDR_ANY, then rpmsg_create_ept will + dynamically assign them an available rpmsg address (drivers should have + a very good reason why not to always use RPMSG_ADDR_ANY here). + + Returns a pointer to the endpoint on success, or NULL on error. + + void rpmsg_destroy_ept(struct rpmsg_endpoint *ept); + - destroys an existing rpmsg endpoint. user should provide a pointer + to an rpmsg endpoint that was previously created with rpmsg_create_ept(). + + int register_rpmsg_driver(struct rpmsg_driver *rpdrv); + - registers an rpmsg driver with the rpmsg bus. user should provide + a pointer to an rpmsg_driver struct, which contains the driver's + ->probe() and ->remove() functions, an rx callback, and an id_table + specifying the names of the channels this driver is interested to + be probed with. + + void unregister_rpmsg_driver(struct rpmsg_driver *rpdrv); + - unregisters an rpmsg driver from the rpmsg bus. user should provide + a pointer to a previously-registered rpmsg_driver struct. + Returns 0 on success, and an appropriate error value on failure. + + +3. Typical usage + +The following is a simple rpmsg driver, that sends an "hello!" message +on probe(), and whenever it receives an incoming message, it dumps its +content to the console. + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/rpmsg.h> + +static void rpmsg_sample_cb(struct rpmsg_channel *rpdev, void *data, int len, + void *priv, u32 src) +{ + print_hex_dump(KERN_INFO, "incoming message:", DUMP_PREFIX_NONE, + 16, 1, data, len, true); +} + +static int rpmsg_sample_probe(struct rpmsg_channel *rpdev) +{ + int err; + + dev_info(&rpdev->dev, "chnl: 0x%x -> 0x%x\n", rpdev->src, rpdev->dst); + + /* send a message on our channel */ + err = rpmsg_send(rpdev, "hello!", 6); + if (err) { + pr_err("rpmsg_send failed: %d\n", err); + return err; + } + + return 0; +} + +static void __devexit rpmsg_sample_remove(struct rpmsg_channel *rpdev) +{ + dev_info(&rpdev->dev, "rpmsg sample client driver is removed\n"); +} + +static struct rpmsg_device_id rpmsg_driver_sample_id_table[] = { + { .name = "rpmsg-client-sample" }, + { }, +}; +MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sample_id_table); + +static struct rpmsg_driver rpmsg_sample_client = { + .drv.name = KBUILD_MODNAME, + .drv.owner = THIS_MODULE, + .id_table = rpmsg_driver_sample_id_table, + .probe = rpmsg_sample_probe, + .callback = rpmsg_sample_cb, + .remove = __devexit_p(rpmsg_sample_remove), +}; + +static int __init init(void) +{ + return register_rpmsg_driver(&rpmsg_sample_client); +} +module_init(init); + +static void __exit fini(void) +{ + unregister_rpmsg_driver(&rpmsg_sample_client); +} +module_exit(fini); + +Note: a similar sample which can be built and loaded can be found +in samples/rpmsg/. + +4. Allocations of rpmsg channels: + +At this point we only support dynamic allocations of rpmsg channels. + +This is possible only with remote processors that have the VIRTIO_RPMSG_F_NS +virtio device feature set. This feature bit means that the remote +processor supports dynamic name service announcement messages. + +When this feature is enabled, creation of rpmsg devices (i.e. channels) +is completely dynamic: the remote processor announces the existence of a +remote rpmsg service by sending a name service message (which contains +the name and rpmsg addr of the remote service, see struct rpmsg_ns_msg). + +This message is then handled by the rpmsg bus, which in turn dynamically +creates and registers an rpmsg channel (which represents the remote service). +If/when a relevant rpmsg driver is registered, it will be immediately probed +by the bus, and can then start sending messages to the remote service. + +The plan is also to add static creation of rpmsg channels via the virtio +config space, but it's not implemented yet. |