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path: root/drivers/clocksource/dw_apb_timer_of.c
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2015-12-15clocksource/drivers/dw_apb_timer_of: Implement ARM delay timerJisheng Zhang
Implement an ARM delay timer to be used for udelay(). This allows us to skip the delay loop calibration at boot on Marvell BG2, BG2Q, BG2CD platforms. And after this patch, udelay() will be unaffected by CPU frequency changes. Note: Although in case there are several possible delay timers, we may not select the "best" delay timer. Take one Marvell Berlin platform for example: we have arch timer and dw-apb timer. The arch timer freq is 25MHZ while the dw-apb timer freq is 100MHZ, current selection would choose the dw-apb timer. But the dw apb timer is on the APB bus while arch timer sits in CPU, the cost of accessing the apb timer is higher than the arch timer. We could introduce "rating" concept to delay timer, but this approach "brings a lot of complexity and workarounds in the code for a small benefit" as pointed out by Daniel. Later, Arnd pointed out "However, we could argue that this actually doesn't matter at all, because the entire point of the ndelay()/ udelay()/mdelay() functions is to waste CPU cycles doing not much at all, so we can just as well waste them reading the timer register than spinning on the CPU reading the arch timer more often.", so we just simply register the dw apb base delay timer. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-03-31clocksource/drivers/dw_apb_timers_of: Fix IO endianness causing time jumpsBen Dooks
The dw_apb_timer_of timer is using __raw_readl() to access the timer register, which is causing issues when the system is running in big endian mode. Fix this by using readl_relaxed() which should account for the endian settings. This fixes issues where the time jumps around in the dmesg output due to returnling __le32 values. For an example, these two console lines show time running backwards: [ 49.882572] CPU1: failed to come online [ 43.282457] Brought up 1 CPUs Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Linux ARM Kernel <linux-arm-kernel@lists.infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: digetx@gmail.com Cc: hdegoede@redhat.com Cc: laurent.pinchart+renesas@ideasonboard.com Cc: maxime.ripard@free-electrons.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1427746633-9137-10-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-23clocksource: dw_apb_timer_of: Do not trace read_sched_clockYang Wei
We do not need to trace read_sched_clock function, so add notrace attribute for this function. Signed-off-by: Yang Wei <Wei.Yang@windriver.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-12-10clocksource: dw_apb_timer_of: Fix support for dts binding "snps,dw-apb-timer"Dinh Nguyen
In commit 620f5e1cbf (dts: Rename DW APB timer compatible strings), both "snps,dw-apb-timer-sp" and "snps,dw-apb-timer-osc" were deprecated in place of "snps,dw-apb-timer". But the driver also needs to be udpated in order to support this new binding "snps,dw-apb-timer". Signed-off-by: Dinh Nguyen <dinguyen@altera.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-12-10clocksource: dw_apb_timer_of: Fix read_sched_clockDinh Nguyen
The read_sched_clock should return the ~value because the clock is a countdown implementation. read_sched_clock() should be the same as __apbt_read_clocksource(). Signed-off-by: Dinh Nguyen <dinguyen@altera.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-02clocksource: dw_apb_timer_of: Mark a few more functions as __initUwe Kleine-König
These are all only called by dw_apb_timer_init which is an __init function, too Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-02clocksource: Put nodes passed to CLOCKSOURCE_OF_DECLARE callbacks centrallyUwe Kleine-König
Instead of letting each driver call of_node_put do it centrally in the loop that also calls the CLOCKSOURCE_OF_DECLARE callbacks. This is less prone to error and also moves getting and putting the references into the same function. Consequently all respective of_node_put calls in drivers are removed. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: David Brown <davidb@codeaurora.org>
2013-07-30clocksource: dw_apb_timer_of: Switch to sched_clock_register()Stephen Boyd
The 32 bit sched_clock interface now supports 64 bits. Upgrade to the 64 bit function to allow us to remove the 32 bit registration interface. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-06Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: "The timer changes contain: - posix timer code consolidation and fixes for odd corner cases - sched_clock implementation moved from ARM to core code to avoid duplication by other architectures - alarm timer updates - clocksource and clockevents unregistration facilities - clocksource/events support for new hardware - precise nanoseconds RTC readout (Xen feature) - generic support for Xen suspend/resume oddities - the usual lot of fixes and cleanups all over the place The parts which touch other areas (ARM/XEN) have been coordinated with the relevant maintainers. Though this results in an handful of trivial to solve merge conflicts, which we preferred over nasty cross tree merge dependencies. The patches which have been committed in the last few days are bug fixes plus the posix timer lot. The latter was in akpms queue and next for quite some time; they just got forgotten and Frederic collected them last minute." * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (59 commits) hrtimer: Remove unused variable hrtimers: Move SMP function call to thread context clocksource: Reselect clocksource when watchdog validated high-res capability posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting posix_timers: fix racy timer delta caching on task exit posix-timers: correctly get dying task time sample in posix_cpu_timer_schedule() selftests: add basic posix timers selftests posix_cpu_timers: consolidate expired timers check posix_cpu_timers: consolidate timer list cleanups posix_cpu_timer: consolidate expiry time type tick: Sanitize broadcast control logic tick: Prevent uncontrolled switch to oneshot mode tick: Make oneshot broadcast robust vs. CPU offlining x86: xen: Sync the CMOS RTC as well as the Xen wallclock x86: xen: Sync the wallclock when the system time is set timekeeping: Indicate that clock was set in the pvclock gtod notifier timekeeping: Pass flags instead of multiple bools to timekeeping_update() xen: Remove clock_was_set() call in the resume path hrtimers: Support resuming with two or more CPUs online (but stopped) timer: Fix jiffies wrap behavior of round_jiffies_common() ...
2013-06-18Revert "dw_apb_timer_of.c: Remove parts that were picoxcell-specific"John Stultz
This reverts commit 55a68c23e0a675b2b8ac2656fd6edbf98b78e4c6. In order to avoid a collision with dw_apb_timer changes in the arm-soc tree, revert this change. I'm leaving it to the arm-soc folks to sort out if they want to keep the other side of the collision or if they're just going to back it all out and try again during the next release cycle. Reported-by: Dinh Nguyen <dinguyen@altera.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-06-12sched_clock: Make ARM's sched_clock generic for all architecturesStephen Boyd
Nothing about the sched_clock implementation in the ARM port is specific to the architecture. Generalize the code so that other architectures can use it by selecting GENERIC_SCHED_CLOCK. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> [jstultz: Merge minor collisions with other patches in my tree] Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-06-12clocksource: dw_apb_timer_of: use clocksource_of_initHeiko Stuebner
dw_apb_timer_init used to search the devicetree for matching timer devices, making calls to it from board files necessary. Change the dw_apb_timer_init to work with CLOCKSOURCE_OF_DECLARE. With this change the function gets called once for each timer node and tracks these number of calls to attach clockevent and clocksource devices to the nodes. Also remove the calls to dw_apb_timer_init from all previous users, as clocksource_of_init is the default for init_time now. Tested on the upcoming rk3066 code. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Dinh Nguyen <dinguyen@altera.com>
2013-06-12clocksource: dw_apb_timer_of: add clock-handlingHeiko Stuebner
Add the possibility to get the clock-frequency from a timer clock instead of specifying it as dt property. Additionally also add the possibility to also define a controlling periphal clock for the timer block. The clock-frequency property is kept to act as fallback if no clocks are specified. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Jamie Iles <jamie@jamieiles.com>
2013-06-12clocksource: dw_apb_timer_of: enable the use the clocksource as sched clockHeiko Stuebner
Currently the dw_apb_timer always expects a separate special timer to be availbable for the sched_clock. Some devices using dw_apb_timers do not have this sptimer but can use the clocksource as sched_clock instead. Therefore enable the driver to distiguish between devices with and without sptimer based on the devicetree data and select the correct timer as sched_clock. Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Jamie Iles <jamie@jamieiles.com>
2013-06-08Merge branch 'timers/clockevents' of ↵Thomas Gleixner
git://git.linaro.org/people/dlezcano/clockevents into timers/core
2013-06-06clocksource: dw_apb: Fix error checkBaruch Siach
irq_of_parse_and_map() returns 0 on error, while the code checks for NO_IRQ. This breaks on platforms that have NO_IRQ != 0. Cc: <stable@vger.kernel.org> Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-05-28clocksource: dw_apb: Remove unused headerBaruch Siach
The time.h header seems not to be used by current code. Removing this include allows the driver to build on other architecture that do not have this header. Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jamie Iles <jamie@jamieiles.com> Cc: Dinh Nguyen <dinguyen@altera.com> Acked-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Baruch Siach <baruch@tkos.co.il> [tweaked commit message and header] Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-28dw_apb_timer_of.c: Remove parts that were picoxcell-specificPavel Machek
It seems we made a mistake when creating dw_apb_timer_of.c: picoxcell sched_clock had parts that were not related to dw_apb_timer, yet we moved them to dw_apb_timer_of, and tried to use them on socfpga. This results in system where user/system time is not measured properly, as demonstrated by time dd if=/dev/urandom of=/dev/zero bs=100000 count=100 So this patch switches sched_clock to hardware that exists on both platforms, and adds missing of_node_put() in dw_apb_timer_init(). Signed-off-by: Pavel Machek <pavel@denx.de> Acked-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2012-12-24ARM: delete struct sys_timerStephen Warren
Now that the only field in struct sys_timer is .init, delete the struct, and replace the machine descriptor .timer field with the initialization function itself. This will enable moving timer drivers into drivers/clocksource without having to place a public prototype of each struct sys_timer object into include/linux; the intent is to create a single of_clocksource_init() function that determines which timer driver to initialize by scanning the device dtree, much like the proposed irqchip_init() at: http://www.spinics.net/lists/arm-kernel/msg203686.html Includes mach-omap2 fixes from Igor Grinberg. Tested-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Stephen Warren <swarren@nvidia.com>
2012-07-12clocksource: dw_apb_timer: Add common DTS glue for dw_apb_timerDinh Nguyen
Make a common device tree glue for clocksource/dw_apb_timer. Move mach-picoxcell/time.c to be a generic device tree application of the dw_apb_timer. Configure mach-picoxcell to use the dw_apb_timer_of device tree implementation in drivers/clocksource. Signed-off-by: Pavel Machek <pavel@denx.de> Signed-off-by: Dinh Nguyen <dinguyen@altera.com> Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>