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2016-08-26clocksource/drivers/sun4i: Clear interrupts after stopping timer in probe ↵Chen-Yu Tsai
function The bootloader (U-boot) sometimes uses this timer for various delays. It uses it as a ongoing counter, and does comparisons on the current counter value. The timer counter is never stopped. In some cases when the user interacts with the bootloader, or lets it idle for some time before loading Linux, the timer may expire, and an interrupt will be pending. This results in an unexpected interrupt when the timer interrupt is enabled by the kernel, at which point the event_handler isn't set yet. This results in a NULL pointer dereference exception, panic, and no way to reboot. Clear any pending interrupts after we stop the timer in the probe function to avoid this. Cc: stable@vger.kernel.org Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2016-06-28clocksources: Switch back to the clksrc tableDaniel Lezcano
All the clocksource drivers's init function are now converted to return an error code. CLOCKSOURCE_OF_DECLARE is no longer used as well as the clksrc-of table. Let's convert back the names: - CLOCKSOURCE_OF_DECLARE_RET => CLOCKSOURCE_OF_DECLARE - clksrc-of-ret => clksrc-of Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> For exynos_mct and samsung_pwm_timer: Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> For arch/arc: Acked-by: Vineet Gupta <vgupta@synopsys.com> For mediatek driver: Acked-by: Matthias Brugger <matthias.bgg@gmail.com> For the Rockchip-part Acked-by: Heiko Stuebner <heiko@sntech.de> For STi : Acked-by: Patrice Chotard <patrice.chotard@st.com> For the mps2-timer.c and versatile.c changes: Acked-by: Liviu Dudau <Liviu.Dudau@arm.com> For the OXNAS part : Acked-by: Neil Armstrong <narmstrong@baylibre.com> For LPC32xx driver: Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com> For Broadcom Kona timer change: Acked-by: Ray Jui <ray.jui@broadcom.com> For Sun4i and Sun5i: Acked-by: Chen-Yu Tsai <wens@csie.org> For Meson6: Acked-by: Carlo Caione <carlo@caione.org> For Keystone: Acked-by: Santosh Shilimkar <ssantosh@kernel.org> For NPS: Acked-by: Noam Camus <noamca@mellanox.com> For bcm2835: Acked-by: Eric Anholt <eric@anholt.net>
2016-06-28clocksource/drivers/sun4i: Convert init function to return errorDaniel Lezcano
The init functions do not return any error. They behave as the following: - panic, thus leading to a kernel crash while another timer may work and make the system boot up correctly or - print an error and let the caller unaware if the state of the system Change that by converting the init functions to return an error conforming to the CLOCKSOURCE_OF_RET prototype. Proper error handling (rollback, errno value) will be changed later case by case, thus this change just return back an error or success in the init function. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-08-10clockevents/drivers/sun4i: Migrate to new 'set-state' interfaceViresh Kumar
Migrate sun4i driver to the new 'set-state' interface provided by clockevents core, the earlier 'set-mode' interface is marked obsolete now. This also enables us to implement callbacks for new states of clockevent devices, for example: ONESHOT_STOPPED. Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2015-03-31clocksource/drivers/sun4i-timer: Only register a sched_clock on sun4i and sun5iHans de Goede
sun6i and newer have an arm arch timer which is a better sched_clock source then the sun4i-timer, and sched_clock does not have priorities, so do not register the sun4i-timer sched_clock at all on sun6i and newer. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: ben.dooks@codethink.co.uk Cc: digetx@gmail.com Cc: laurent.pinchart+renesas@ideasonboard.com Cc: linux-arm-kernel@lists.infradead.org Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1427746633-9137-8-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-19clockevent: sun4i: Fix race condition in the probe codeMaxime Ripard
The interrupts were activated and the handler registered before the clockevent was registered in the probe function. The interrupt handler, however, was making the assumption that the clockevent device was registered. That could cause a null pointer dereference if the timer interrupt was firing during this narrow window. Fix that by moving the clockevent registration before the interrupt is enabled. Reported-by: Roman Byshko <rbyshko@gmail.com> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Cc: stable@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-03-11clocksource: sunxi: Add new compatiblesMaxime Ripard
The Allwinner A10 compatibles were following a slightly different compatible patterns than the rest of the SoCs for historical reasons. Add compatibles matching the other pattern to the timer driver for consistency, and keep the older one for backward compatibility. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-01-14Merge branch 'clockevents/3.14' of ↵Ingo Molnar
git://git.linaro.org/people/daniel.lezcano/linux into timers/core Pull clocksource/clockevent updates from Daniel Lezcano: * Axel Lin removed an unused structure defining the ids for the bcm kona driver. * Ezequiel Garcia enabled the timer divider only when the 25MHz timer is not used for the armada 370 XP. * Jingoo Han removed a pointless platform data initialization for the sh_mtu and sh_mtu2. * Laurent Pinchart added the clk_prepare/clk_unprepare for sh_cmt. * Linus Walleij added a useful warning in clk_of when no clocks are found while the old behavior was to silently hang at boot time. * Maxime Ripard added the high speed timer drivers for the Allwinner SoCs (A10, A13, A20). He increased the rating, shared the irq across all available cpus and fixed the clockevent's irq initialization for the sun4i. * Michael Opdenacker removed the usage of the IRQF_DISABLED for the all the timers driver located in drivers/clocksource. * Stephen Boyd switched to sched_clock_register for the arm_global_timer, cadence_ttc, sun4i and orion timers. Conflicts: drivers/clocksource/clksrc-of.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-12-11clocksource: sun4i: 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. While we're here, mark the sched_clock function as notrace to prevent ftrace recursion crashes. Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-12-11clocksource: sun4i: Increase a bit the clock event and sources ratingMaxime Ripard
We want to keep this driver as the default provider of the clock events and source, yet some other driver might fit in the "desired" category of ratings. Hence, we need to increase a bit the rating so that we can have more flexibility in the ratings we choose. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Tested-by: Emilio López <emilio@elopez.com.ar> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-12-11clocksource: sun4i: Change CPU mask to cpu_possible_maskMaxime Ripard
The interrupt for the timer is a shared processor interrupt, so any CPU found in the system can handle it. Switch to our cpumask to cpu_possible_mask instead of cpumask_of(0). Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2013-12-11clockevent: sun4i: Fill the irq field in the clockevent structureMaxime Ripard
The clock event structure irq field was not filled previously to the interrupt we're using. This was resulting in the timer not being used at all when using a configuration with SMP enabled on a system with several CPUs, and with the cpumask set to the cpu_possible_mask. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2013-12-10clocksource: sunxi: Stop timer from ticking before enabling interruptsMarc Zyngier
The sun4i timer can still be ticking when we enable the interrupt. If another timer is actually used (A7 architected timer, for example), odds are that the interrupt will eventually fire with the event_handler pointer being NULL. The obvious fix it to stop the timer before registering the interrupt. Observed and tested on sun7i (cubietruck). Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-22clocksource: sun4i: remove IRQF_DISABLEDMaxime Ripard
IRQF_DISABLED is a no-op nowadays, so we can safely remove it. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-10-22clocksource: sun4i: Report the minimum tick that we can programMaxime Ripard
We need to wait for at least 2 clock cycles whenever we reprogram our clockevent timer. Report that the minimum number of ticks we can handle is 3 ticks, and remove 3 ticks to the interval programmed to reflect this. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Fix bug when switching from periodic to oneshot modesMaxime Ripard
The interval was firing at was set up at probe time, and only changed in the set_next_event, and never changed back, which is not really what is expected. When enabling the periodic mode, now set an interval to tick every jiffy. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Cleanup parent clock setupMaxime Ripard
The current bring-up code for the timer was overly complicated. The only thing we need is actually which clock we want to use as source and that's pretty much all. Let's keep it that way. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Remove TIMER_SCAL variableMaxime Ripard
The prescaler is only used when using the internal low frequency oscillator (at 32kHz). Since we're using the higher frequency oscillator at 24MHz, we can just remove it. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Factor out some timer codeMaxime Ripard
The set_next_event and set_mode callbacks share a lot of common code we can easily factor to avoid duplication and mistakes. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Fix the next event codeMaxime Ripard
The next_event logic was setting the next interval to fire in the current timer value instead of the interval value register, which is obviously wrong. Plus, the logic to set the actual value was wrong as well: the interval register can only be modified when the timer is disabled, and then enable it back, otherwise, it'll have no effect. Fix this logic as well since that code couldn't possibly work. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Don't forget to enable the clock we useMaxime Ripard
Even if in our case, this clock was non-gatable, used as a parent clock for several IPs, it still is a good idea to enable it. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Add clocksource and sched clock driversMaxime Ripard
Use the second timer found on the Allwinner SoCs as a clock source and sched clock, that were both not used yet on these platforms. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: rename AUTORELOAD define to RELOADMaxime Ripard
The name AUTORELOAD was actually pretty bad since it doesn't make the register reload the previous interval when it expires, but setting this value pushes the new programmed interval to the internal timer counter. Rename it to RELOAD instead. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Wrap macros arguments in parenthesisMaxime Ripard
The macros were not using parenthesis to escape the arguments passed to them. It is pretty unsafe, so add those parenthesis. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-07-18clocksource: sun4i: Use the BIT macros where possibleMaxime Ripard
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2013-04-08clocksource: sunxi: Rename sunxi to sun4iMaxime Ripard
During the introduction of the Allwinner SoC platforms, sunxi was initially meant as a generic name for all the variants of the Allwinner SoC. It was ok at the time of the support of only the A10 and A13 that looks pretty much the same, but it's beginning to be troublesome with the future addition of the Allwinner A31 (sun6i) that is quite different, and would introduce some weird logic, where sunxi would actually mean in some case sun4i and sun5i but without sun6i... Moreover, it makes the compatible strings naming scheme not consistent with other architectures, where usually for this kind of compability, we just use the oldest SoC name that has this IP, so let's do just this. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>