diff options
Diffstat (limited to 'Documentation')
25 files changed, 861 insertions, 325 deletions
diff --git a/Documentation/acpi-hotkey.txt b/Documentation/acpi-hotkey.txt deleted file mode 100644 index 38040fa3764..00000000000 --- a/Documentation/acpi-hotkey.txt +++ /dev/null @@ -1,38 +0,0 @@ -driver/acpi/hotkey.c implement: -1. /proc/acpi/hotkey/event_config -(event based hotkey or event config interface): -a. add a event based hotkey(event) : -echo "0:bus::action:method:num:num" > event_config - -b. delete a event based hotkey(event): -echo "1:::::num:num" > event_config - -c. modify a event based hotkey(event): -echo "2:bus::action:method:num:num" > event_config - -2. /proc/acpi/hotkey/poll_config -(polling based hotkey or event config interface): -a.add a polling based hotkey(event) : -echo "0:bus:method:action:method:num" > poll_config -this adding command will create a proc file -/proc/acpi/hotkey/method, which is used to get -result of polling. - -b.delete a polling based hotkey(event): -echo "1:::::num" > event_config - -c.modify a polling based hotkey(event): -echo "2:bus:method:action:method:num" > poll_config - -3./proc/acpi/hotkey/action -(interface to call aml method associated with a -specific hotkey(event)) -echo "event_num:event_type:event_argument" > - /proc/acpi/hotkey/action. -The result of the execution of this aml method is -attached to /proc/acpi/hotkey/poll_method, which is dynamically -created. Please use command "cat /proc/acpi/hotkey/polling_method" -to retrieve it. - -Note: Use cmdline "acpi_generic_hotkey" to over-ride -platform-specific with generic driver. diff --git a/Documentation/arm/Samsung-S3C24XX/DMA.txt b/Documentation/arm/Samsung-S3C24XX/DMA.txt new file mode 100644 index 00000000000..37f4edcc5d8 --- /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 flexibilty for each cpu type and board, the + dma code can be given an 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 + orred 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 an complete ordering set. The routine will + copy the data, so the original can be discared with + __initdata. + + +Authour +------- + +Ben Dooks, +Copyright (c) 2007 Ben Dooks, Simtec Electronics +Licensed under the GPL v2 diff --git a/Documentation/arm/Samsung-S3C24XX/Overview.txt b/Documentation/arm/Samsung-S3C24XX/Overview.txt index 28d014714ab..c31b76fa66c 100644 --- a/Documentation/arm/Samsung-S3C24XX/Overview.txt +++ b/Documentation/arm/Samsung-S3C24XX/Overview.txt @@ -8,13 +8,10 @@ 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, S3C2440 and S3C2442 devices are supported. Support for the S3C2400 series is in progress. - Support for the S3C2412 and S3C2413 CPUs is being merged. - - Configuration ------------- @@ -26,6 +23,22 @@ 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 + include/asm-arm/arch-s3c2410 directory. + + Machines -------- diff --git a/Documentation/driver-model/platform.txt b/Documentation/driver-model/platform.txt index 9f0bc3bfd77..f7c9262b2dc 100644 --- a/Documentation/driver-model/platform.txt +++ b/Documentation/driver-model/platform.txt @@ -66,7 +66,7 @@ runtime memory footprint: Device Enumeration ~~~~~~~~~~~~~~~~~~ -As a rule, platform specific (and often board-specific) setup code wil +As a rule, platform specific (and often board-specific) setup code will register platform devices: int platform_device_register(struct platform_device *pdev); @@ -106,7 +106,7 @@ It's built from two components: * platform_device.id ... the device instance number, or else "-1" to indicate there's only one. -These are catenated, so name/id "serial"/0 indicates bus_id "serial.0", and +These are concatenated, so name/id "serial"/0 indicates bus_id "serial.0", and "serial/3" indicates bus_id "serial.3"; both would use the platform_driver named "serial". While "my_rtc"/-1 would be bus_id "my_rtc" (no instance id) and use the platform_driver called "my_rtc". diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index c585aa8d62b..6a451f47d40 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt @@ -253,29 +253,6 @@ Who: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> --------------------------- -<<<<<<< test:Documentation/feature-removal-schedule.txt -What: ACPI hotkey driver (CONFIG_ACPI_HOTKEY) -When: 2.6.21 -Why: hotkey.c was an attempt to consolidate multiple drivers that use - ACPI to implement hotkeys. However, hotkeys are not documented - in the ACPI specification, so the drivers used undocumented - vendor-specific hooks and turned out to be more different than - the same. - - Further, the keys and the features supplied by each platform - are different, so there will always be a need for - platform-specific drivers. - - So the new plan is to delete hotkey.c and instead, work on the - platform specific drivers to try to make them look the same - to the user when they supply the same features. - - hotkey.c has always depended on CONFIG_EXPERIMENTAL - -Who: Len Brown <len.brown@intel.com> - ---------------------------- - What: /sys/firmware/acpi/namespace When: 2.6.21 Why: The ACPI namespace is effectively the symbol list for @@ -306,13 +283,6 @@ Who: Len Brown <len.brown@intel.com> --------------------------- -What: JFFS (version 1) -When: 2.6.21 -Why: Unmaintained for years, superceded by JFFS2 for years. -Who: Jeff Garzik <jeff@garzik.org> - ---------------------------- - What: sk98lin network driver When: July 2007 Why: In kernel tree version of driver is unmaintained. Sk98lin driver diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX index 4dc28cc9350..571785887a4 100644 --- a/Documentation/filesystems/00-INDEX +++ b/Documentation/filesystems/00-INDEX @@ -4,6 +4,8 @@ Exporting - explanation of how to make filesystems exportable. Locking - info on locking rules as they pertain to Linux VFS. +9p.txt + - 9p (v9fs) is an implementation of the Plan 9 remote fs protocol. adfs.txt - info and mount options for the Acorn Advanced Disc Filing System. afs.txt @@ -82,8 +84,6 @@ udf.txt - info and mount options for the UDF filesystem. ufs.txt - info on the ufs filesystem. -v9fs.txt - - v9fs is a Unix implementation of the Plan 9 9p remote fs protocol. vfat.txt - info on using the VFAT filesystem used in Windows NT and Windows 95 vfs.txt diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt index 4d075a4558f..bbd8b28c13d 100644 --- a/Documentation/filesystems/9p.txt +++ b/Documentation/filesystems/9p.txt @@ -40,6 +40,10 @@ OPTIONS aname=name aname specifies the file tree to access when the server is offering several exported file systems. + cache=mode specifies a cacheing policy. By default, no caches are used. + loose = no attempts are made at consistency, + intended for exclusive, read-only mounts + debug=n specifies debug level. The debug level is a bitmask. 0x01 = display verbose error messages 0x02 = developer debug (DEBUG_CURRENT) diff --git a/Documentation/filesystems/sysfs-pci.txt b/Documentation/filesystems/sysfs-pci.txt index 7ba2baa165f..5daa2aaec2c 100644 --- a/Documentation/filesystems/sysfs-pci.txt +++ b/Documentation/filesystems/sysfs-pci.txt @@ -65,7 +65,7 @@ Accessing legacy resources through sysfs ---------------------------------------- Legacy I/O port and ISA memory resources are also provided in sysfs if the -underlying platform supports them. They're located in the PCI class heirarchy, +underlying platform supports them. They're located in the PCI class hierarchy, e.g. /sys/class/pci_bus/0000:17/ diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt index 09dd510c4a5..576ce463cf4 100644 --- a/Documentation/gpio.txt +++ b/Documentation/gpio.txt @@ -78,7 +78,8 @@ Identifying GPIOs ----------------- GPIOs are identified by unsigned integers in the range 0..MAX_INT. That reserves "negative" numbers for other purposes like marking signals as -"not available on this board", or indicating faults. +"not available on this board", or indicating faults. Code that doesn't +touch the underlying hardware treats these integers as opaque cookies. Platforms define how they use those integers, and usually #define symbols for the GPIO lines so that board-specific setup code directly corresponds @@ -139,10 +140,10 @@ issues including wire-OR and output latencies. The get/set calls have no error returns because "invalid GPIO" should have been reported earlier in gpio_set_direction(). However, note that not all platforms can read the value of output pins; those that can't should always -return zero. Also, these calls will be ignored for GPIOs that can't safely -be accessed wihtout sleeping (see below). +return zero. Also, using these calls for GPIOs that can't safely be accessed +without sleeping (see below) is an error. -Platform-specific implementations are encouraged to optimise the two +Platform-specific implementations are encouraged to optimize the two calls to access the GPIO value in cases where the GPIO number (and for output, value) are constant. It's normal for them to need only a couple of instructions in such cases (reading or writing a hardware register), @@ -239,7 +240,8 @@ options are part of the IRQ interface, e.g. IRQF_TRIGGER_FALLING, as are system wakeup capabilities. Non-error values returned from irq_to_gpio() would most commonly be used -with gpio_get_value(). +with gpio_get_value(), for example to initialize or update driver state +when the IRQ is edge-triggered. @@ -260,9 +262,10 @@ pullups (or pulldowns) so that the on-chip ones should not be used. There are other system-specific mechanisms that are not specified here, like the aforementioned options for input de-glitching and wire-OR output. Hardware may support reading or writing GPIOs in gangs, but that's usually -configuration dependednt: for GPIOs sharing the same bank. (GPIOs are +configuration dependent: for GPIOs sharing the same bank. (GPIOs are commonly grouped in banks of 16 or 32, with a given SOC having several such -banks.) Code relying on such mechanisms will necessarily be nonportable. +banks.) Some systems can trigger IRQs from output GPIOs. Code relying on +such mechanisms will necessarily be nonportable. Dynamic definition of GPIOs is not currently supported; for example, as a side effect of configuring an add-on board with some GPIO expanders. diff --git a/Documentation/hrtimer/timer_stats.txt b/Documentation/hrtimer/timer_stats.txt new file mode 100644 index 00000000000..27f782e3593 --- /dev/null +++ b/Documentation/hrtimer/timer_stats.txt @@ -0,0 +1,68 @@ +timer_stats - timer usage statistics +------------------------------------ + +timer_stats is a debugging facility to make the timer (ab)usage in a Linux +system visible to kernel and userspace developers. It is not intended for +production usage as it adds significant overhead to the (hr)timer code and the +(hr)timer data structures. + +timer_stats should be used by kernel and userspace developers to verify that +their code does not make unduly use of timers. This helps to avoid unnecessary +wakeups, which should be avoided to optimize power consumption. + +It can be enabled by CONFIG_TIMER_STATS in the "Kernel hacking" configuration +section. + +timer_stats collects information about the timer events which are fired in a +Linux system over a sample period: + +- the pid of the task(process) which initialized the timer +- the name of the process which initialized the timer +- the function where the timer was intialized +- the callback function which is associated to the timer +- the number of events (callbacks) + +timer_stats adds an entry to /proc: /proc/timer_stats + +This entry is used to control the statistics functionality and to read out the +sampled information. + +The timer_stats functionality is inactive on bootup. + +To activate a sample period issue: +# echo 1 >/proc/timer_stats + +To stop a sample period issue: +# echo 0 >/proc/timer_stats + +The statistics can be retrieved by: +# cat /proc/timer_stats + +The readout of /proc/timer_stats automatically disables sampling. The sampled +information is kept until a new sample period is started. This allows multiple +readouts. + +Sample output of /proc/timer_stats: + +Timerstats sample period: 3.888770 s + 12, 0 swapper hrtimer_stop_sched_tick (hrtimer_sched_tick) + 15, 1 swapper hcd_submit_urb (rh_timer_func) + 4, 959 kedac schedule_timeout (process_timeout) + 1, 0 swapper page_writeback_init (wb_timer_fn) + 28, 0 swapper hrtimer_stop_sched_tick (hrtimer_sched_tick) + 22, 2948 IRQ 4 tty_flip_buffer_push (delayed_work_timer_fn) + 3, 3100 bash schedule_timeout (process_timeout) + 1, 1 swapper queue_delayed_work_on (delayed_work_timer_fn) + 1, 1 swapper queue_delayed_work_on (delayed_work_timer_fn) + 1, 1 swapper neigh_table_init_no_netlink (neigh_periodic_timer) + 1, 2292 ip __netdev_watchdog_up (dev_watchdog) + 1, 23 events/1 do_cache_clean (delayed_work_timer_fn) +90 total events, 30.0 events/sec + +The first column is the number of events, the second column the pid, the third +column is the name of the process. The forth column shows the function which +initialized the timer and in parantheses the callback function which was +executed on expiry. + + Thomas, Ingo + diff --git a/Documentation/hrtimers/highres.txt b/Documentation/hrtimers/highres.txt new file mode 100644 index 00000000000..ce0e9a91e15 --- /dev/null +++ b/Documentation/hrtimers/highres.txt @@ -0,0 +1,249 @@ +High resolution timers and dynamic ticks design notes +----------------------------------------------------- + +Further information can be found in the paper of the OLS 2006 talk "hrtimers +and beyond". The paper is part of the OLS 2006 Proceedings Volume 1, which can +be found on the OLS website: +http://www.linuxsymposium.org/2006/linuxsymposium_procv1.pdf + +The slides to this talk are available from: +http://tglx.de/projects/hrtimers/ols2006-hrtimers.pdf + +The slides contain five figures (pages 2, 15, 18, 20, 22), which illustrate the +changes in the time(r) related Linux subsystems. Figure #1 (p. 2) shows the +design of the Linux time(r) system before hrtimers and other building blocks +got merged into mainline. + +Note: the paper and the slides are talking about "clock event source", while we +switched to the name "clock event devices" in meantime. + +The design contains the following basic building blocks: + +- hrtimer base infrastructure +- timeofday and clock source management +- clock event management +- high resolution timer functionality +- dynamic ticks + + +hrtimer base infrastructure +--------------------------- + +The hrtimer base infrastructure was merged into the 2.6.16 kernel. Details of +the base implementation are covered in Documentation/hrtimers/hrtimer.txt. See +also figure #2 (OLS slides p. 15) + +The main differences to the timer wheel, which holds the armed timer_list type +timers are: + - time ordered enqueueing into a rb-tree + - independent of ticks (the processing is based on nanoseconds) + + +timeofday and clock source management +------------------------------------- + +John Stultz's Generic Time Of Day (GTOD) framework moves a large portion of +code out of the architecture-specific areas into a generic management +framework, as illustrated in figure #3 (OLS slides p. 18). The architecture +specific portion is reduced to the low level hardware details of the clock +sources, which are registered in the framework and selected on a quality based +decision. The low level code provides hardware setup and readout routines and +initializes data structures, which are used by the generic time keeping code to +convert the clock ticks to nanosecond based time values. All other time keeping +related functionality is moved into the generic code. The GTOD base patch got +merged into the 2.6.18 kernel. + +Further information about the Generic Time Of Day framework is available in the +OLS 2005 Proceedings Volume 1: +http://www.linuxsymposium.org/2005/linuxsymposium_procv1.pdf + +The paper "We Are Not Getting Any Younger: A New Approach to Time and +Timers" was written by J. Stultz, D.V. Hart, & N. Aravamudan. + +Figure #3 (OLS slides p.18) illustrates the transformation. + + +clock event management +---------------------- + +While clock sources provide read access to the monotonically increasing time +value, clock event devices are used to schedule the next event +interrupt(s). The next event is currently defined to be periodic, with its +period defined at compile time. The setup and selection of the event device +for various event driven functionalities is hardwired into the architecture +dependent code. This results in duplicated code across all architectures and +makes it extremely difficult to change the configuration of the system to use +event interrupt devices other than those already built into the +architecture. Another implication of the current design is that it is necessary +to touch all the architecture-specific implementations in order to provide new +functionality like high resolution timers or dynamic ticks. + +The clock events subsystem tries to address this problem by providing a generic +solution to manage clock event devices and their usage for the various clock +event driven kernel functionalities. The goal of the clock event subsystem is +to minimize the clock event related architecture dependent code to the pure +hardware related handling and to allow easy addition and utilization of new +clock event devices. It also minimizes the duplicated code across the +architectures as it provides generic functionality down to the interrupt +service handler, which is almost inherently hardware dependent. + +Clock event devices are registered either by the architecture dependent boot +code or at module insertion time. Each clock event device fills a data +structure with clock-specific property parameters and callback functions. The +clock event management decides, by using the specified property parameters, the +set of system functions a clock event device will be used to support. This +includes the distinction of per-CPU and per-system global event devices. + +System-level global event devices are used for the Linux periodic tick. Per-CPU +event devices are used to provide local CPU functionality such as process +accounting, profiling, and high resolution timers. + +The management layer assignes one or more of the folliwing functions to a clock +event device: + - system global periodic tick (jiffies update) + - cpu local update_process_times + - cpu local profiling + - cpu local next event interrupt (non periodic mode) + +The clock event device delegates the selection of those timer interrupt related +functions completely to the management layer. The clock management layer stores +a function pointer in the device description structure, which has to be called +from the hardware level handler. This removes a lot of duplicated code from the +architecture specific timer interrupt handlers and hands the control over the +clock event devices and the assignment of timer interrupt related functionality +to the core code. + +The clock event layer API is rather small. Aside from the clock event device +registration interface it provides functions to schedule the next event +interrupt, clock event device notification service and support for suspend and +resume. + +The framework adds about 700 lines of code which results in a 2KB increase of +the kernel binary size. The conversion of i386 removes about 100 lines of +code. The binary size decrease is in the range of 400 byte. We believe that the +increase of flexibility and the avoidance of duplicated code across +architectures justifies the slight increase of the binary size. + +The conversion of an architecture has no functional impact, but allows to +utilize the high resolution and dynamic tick functionalites without any change +to the clock event device and timer interrupt code. After the conversion the +enabling of high resolution timers and dynamic ticks is simply provided by +adding the kernel/time/Kconfig file to the architecture specific Kconfig and +adding the dynamic tick specific calls to the idle routine (a total of 3 lines +added to the idle function and the Kconfig file) + +Figure #4 (OLS slides p.20) illustrates the transformation. + + +high resolution timer functionality +----------------------------------- + +During system boot it is not possible to use the high resolution timer +functionality, while making it possible would be difficult and would serve no +useful function. The initialization of the clock event device framework, the +clock source framework (GTOD) and hrtimers itself has to be done and +appropriate clock sources and clock event devices have to be registered before +the high resolution functionality can work. Up to the point where hrtimers are +initialized, the system works in the usual low resolution periodic mode. The +clock source and the clock event device layers provide notification functions +which inform hrtimers about availability of new hardware. hrtimers validates +the usability of the registered clock sources and clock event devices before +switching to high resolution mode. This ensures also that a kernel which is +configured for high resolution timers can run on a system which lacks the +necessary hardware support. + +The high resolution timer code does not support SMP machines which have only +global clock event devices. The support of such hardware would involve IPI +calls when an interrupt happens. The overhead would be much larger than the +benefit. This is the reason why we currently disable high resolution and +dynamic ticks on i386 SMP systems which stop the local APIC in C3 power +state. A workaround is available as an idea, but the problem has not been +tackled yet. + +The time ordered insertion of timers provides all the infrastructure to decide +whether the event device has to be reprogrammed when a timer is added. The +decision is made per timer base and synchronized across per-cpu timer bases in +a support function. The design allows the system to utilize separate per-CPU +clock event devices for the per-CPU timer bases, but currently only one +reprogrammable clock event device per-CPU is utilized. + +When the timer interrupt happens, the next event interrupt handler is called +from the clock event distribution code and moves expired timers from the +red-black tree to a separate double linked list and invokes the softirq +handler. An additional mode field in the hrtimer structure allows the system to +execute callback functions directly from the next event interrupt handler. This +is restricted to code which can safely be executed in the hard interrupt +context. This applies, for example, to the common case of a wakeup function as +used by nanosleep. The advantage of executing the handler in the interrupt +context is the avoidance of up to two context switches - from the interrupted +context to the softirq and to the task which is woken up by the expired +timer. + +Once a system has switched to high resolution mode, the periodic tick is +switched off. This disables the per system global periodic clock event device - +e.g. the PIT on i386 SMP systems. + +The periodic tick functionality is provided by an per-cpu hrtimer. The callback +function is executed in the next event interrupt context and updates jiffies +and calls update_process_times and profiling. The implementation of the hrtimer +based periodic tick is designed to be extended with dynamic tick functionality. +This allows to use a single clock event device to schedule high resolution +timer and periodic events (jiffies tick, profiling, process accounting) on UP +systems. This has been proved to work with the PIT on i386 and the Incrementer +on PPC. + +The softirq for running the hrtimer queues and executing the callbacks has been +separated from the tick bound timer softirq to allow accurate delivery of high +resolution timer signals which are used by itimer and POSIX interval +timers. The execution of this softirq can still be delayed by other softirqs, +but the overall latencies have been significantly improved by this separation. + +Figure #5 (OLS slides p.22) illustrates the transformation. + + +dynamic ticks +------------- + +Dynamic ticks are the logical consequence of the hrtimer based periodic tick +replacement (sched_tick). The functionality of the sched_tick hrtimer is +extended by three functions: + +- hrtimer_stop_sched_tick +- hrtimer_restart_sched_tick +- hrtimer_update_jiffies + +hrtimer_stop_sched_tick() is called when a CPU goes into idle state. The code +evaluates the next scheduled timer event (from both hrtimers and the timer +wheel) and in case that the next event is further away than the next tick it +reprograms the sched_tick to this future event, to allow longer idle sleeps +without worthless interruption by the periodic tick. The function is also +called when an interrupt happens during the idle period, which does not cause a +reschedule. The call is necessary as the interrupt handler might have armed a +new timer whose expiry time is before the time which was identified as the +nearest event in the previous call to hrtimer_stop_sched_tick. + +hrtimer_restart_sched_tick() is called when the CPU leaves the idle state before +it calls schedule(). hrtimer_restart_sched_tick() resumes the periodic tick, +which is kept active until the next call to hrtimer_stop_sched_tick(). + +hrtimer_update_jiffies() is called from irq_enter() when an interrupt happens +in the idle period to make sure that jiffies are up to date and the interrupt +handler has not to deal with an eventually stale jiffy value. + +The dynamic tick feature provides statistical values which are exported to +userspace via /proc/stats and can be made available for enhanced power +management control. + +The implementation leaves room for further development like full tickless +systems, where the time slice is controlled by the scheduler, variable +frequency profiling, and a complete removal of jiffies in the future. + + +Aside the current initial submission of i386 support, the patchset has been +extended to x86_64 and ARM already. Initial (work in progress) support is also +available for MIPS and PowerPC. + + Thomas, Ingo + + + diff --git a/Documentation/hrtimers.txt b/Documentation/hrtimers/hrtimers.txt index ce31f65e12e..ce31f65e12e 100644 --- a/Documentation/hrtimers.txt +++ b/Documentation/hrtimers/hrtimers.txt diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index 4b3d6710c50..bb5306e9a5c 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -34,7 +34,7 @@ This document describes the Linux kernel Makefiles. --- 6.1 Set variables to tweak the build to the architecture --- 6.2 Add prerequisites to archprepare: --- 6.3 List directories to visit when descending - --- 6.4 Architecture specific boot images + --- 6.4 Architecture-specific boot images --- 6.5 Building non-kbuild targets --- 6.6 Commands useful for building a boot image --- 6.7 Custom kbuild commands @@ -124,7 +124,7 @@ more details, with real examples. Example: obj-y += foo.o - This tell kbuild that there is one object in that directory, named + This tells kbuild that there is one object in that directory, named foo.o. foo.o will be built from foo.c or foo.S. If foo.o shall be built as a module, the variable obj-m is used. @@ -353,7 +353,7 @@ more details, with real examples. Special rules are used when the kbuild infrastructure does not provide the required support. A typical example is header files generated during the build process. - Another example are the architecture specific Makefiles which + Another example are the architecture-specific Makefiles which need special rules to prepare boot images etc. Special rules are written as normal Make rules. @@ -416,7 +416,7 @@ more details, with real examples. #arch/i386/kernel/Makefile vsyscall-flags += $(call ld-option, -Wl$(comma)--hash-style=sysv) - In the above example vsyscall-flags will be assigned the option + In the above example, vsyscall-flags will be assigned the option -Wl$(comma)--hash-style=sysv if it is supported by $(CC). The second argument is optional, and if supplied will be used if first argument is not supported. @@ -434,7 +434,7 @@ more details, with real examples. #arch/i386/Makefile cflags-y += $(call cc-option,-march=pentium-mmx,-march=i586) - In the above example cflags-y will be assigned the option + In the above example, cflags-y will be assigned the option -march=pentium-mmx if supported by $(CC), otherwise -march=i586. The second argument to cc-option is optional, and if omitted, cflags-y will be assigned no value if first option is not supported. |