Erratum A-008585 says that the ARM generic timer counter "has the
potential to contain an erroneous value for a small number of core
clock cycles every time the timer value changes".  Accesses to TVAL
(both read and write) are also affected due to the implicit counter
read.  Accesses to CVAL are not affected.

The workaround is to reread TVAL and count registers until successive
reads return the same value.  Writes to TVAL are replaced with an
equivalent write to CVAL.

The workaround is to reread TVAL and count registers until successive reads
return the same value, and when writing TVAL to retry until counter
reads before and after the write return the same value.

The workaround is enabled if the fsl,erratum-a008585 property is found in
the timer node in the device tree.  This can be overridden with the
clocksource.arm_arch_timer.fsl-a008585 boot parameter, which allows KVM
users to enable the workaround until a mechanism is implemented to
automatically communicate this information.

This erratum can be found on LS1043A and LS2080A.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NScott Wood <oss@buserror.net>
[will: renamed read macro to reflect that it's not usually unstable]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Disabling the eventstream can be useful for both remotely debugging a
deployed production system and development of code using WFE-based
polling loops. Whilst this can currently be controlled via a Kconfig
option (CONFIG_ARM_ARCH_TIMER_EVTSTREAM), it's often desirable to toggle
the feature on the command line, so this patch adds a new command-line
option ("clocksource.arm_arch_timer.evtstrm") to do just that. The
default behaviour is determined based on CONFIG_ARM_ARCH_TIMER_EVTSTREAM.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach,
allowing the user to compile the driver on different platforms.

The current option let the user to select the clocksource or not.

The Kconfig option policy is to let the platform to select the
timer automatically.

Add the COMPILE_TEST option, so the prompt to select the driver will
be showed only when COMPILE_TEST is set and will let this driver
to compile on different platform, thus increasing the compilation
test coverage.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach,
allowing the user to compile the driver on different platforms.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach,
allowing the user to compile the driver on different platforms.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_INTEGRATOR_AP_TIMER and is selected
by the platform. Then the clocksource's Kconfig is changed to make this
option selectable by the user if the COMPILE_TEST option is set. Otherwise,
it is up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_KEYSTONE_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_NSPIRE_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_U300_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.

Due on the delay specific code, this driver will compile only on the ARM
architecture.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_PRIMA2_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_MXS_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_MOXART_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_ATLAS7_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_CLPS711X_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_BCM_KONA_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it is
up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

In order to increase the compilation test coverage, add the COMPILE_TEST
so the driver can be compiled even if it does not belong to the platform
or the architecture.

The io.h header inclusion is also added as it the driver does not compile
on UM platform.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Change the Kconfig option logic to fullfil with the current approach.

A new Kconfig option is added, CONFIG_BCM2835_TIMER and is selected by the
platform. Then the clocksource's Kconfig is changed to make this option
selectable by the user if the COMPILE_TEST option is set. Otherwise, it
is up to the platform's Kconfig to select the timer.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Add clocksource and clockevent driver from dual RPS timer.
The HW provides a dual one-shot or periodic 24bit timers,
the drivers set the first one as tick event source and the
second as a continuous scheduler clock source.
The timer can use 1, 16 or 256 as pre-dividers, thus the
clocksource uses 16 by default.

CC: Ma Haijun <mahaijuns@gmail.com>
Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Correct the typo in "driver" word in the option description.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Add internal tick generator which is shared by all cores.
Each cluster of cores view it through dedicated address.
This is used for SMP system where all CPUs synced by same
clock source.
Signed-off-by: NNoam Camus <noamc@ezchip.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

MPS2 platform has simple 32 bits general purpose countdown timers.

The driver uses the first detected timer as a clocksource and the rest
of the timers as a clockevent
Acked-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

This commit implements the ARM timer-based delay timer for the
LPC32xx, LPC18xx, LPC43xx family of SoCs.

Also, add a dependency to restrict compiling this driver for
the ARM architecture.
Signed-off-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NJoachim Eastwood <manabian@gmail.com>
Tested-by: NJoachim Eastwood <manabian@gmail.com>

Not every arch has io memory.
So, unbreak the build by fixing the dependencies.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Cc: user-mode-linux-devel@lists.sourceforge.net
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: http://lkml.kernel.org/r/1453760661-1444-21-git-send-email-richard@nod.atSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The Tegra clocksource implementation uses the clocksource_mmio helper
functions, but currently can be configured without them, which fails:

drivers/clocksource/built-in.o: In function `tegra20_init_timer':
:(.init.text+0xac): undefined reference to `clocksource_mmio_init'
:(.init.text+0x140): undefined reference to `clocksource_mmio_readl_up'

The same problem exists for Digicolor:

drivers/clocksource/built-in.o: In function `digicolor_timer_init':
:(.init.text+0xfa): undefined reference to `clocksource_mmio_init'
:(.init.text+0x14c): undefined reference to `clocksource_mmio_readl_down'

I've inspected the Kconfig file to look for other cases that I have not
yet run into, and added an explicit 'select' to each one to ensure we
can successfully link the drivers.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: http://lkml.kernel.org/r/1453737776-1960372-1-git-send-email-arnd@arndb.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Select CLKSRC_MMIO when FSL_FTM_TIMER is enabled. Otherwise it fails to
compile on i386 with COMPILE_TEST=y.

"
on i386:
when CLKSRC_MMIO is not enabled:

drivers/built-in.o: In function `ftm_timer_init':
fsl_ftm_timer.c:(.init.text+0x6842): undefined reference to `clocksource_mmio_readl_up'
fsl_ftm_timer.c:(.init.text+0x6855): undefined reference to `clocksource_mmio_init'
"
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Not every arch has io memory.

So, unbreak the build by fixing the dependencies.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

The current code to initialize, register and read the clocksource is
already factored out in mmio.c via the clocksource_mmio_init function.

Factor out the code with the clocksource_mmio_init function.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Add the COMPILE_TEST option so the drivers can be compiled on different
architecture with the 'allyesconfig' kernel configuration.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

The current Kconfig option is the H8300 arch option. In order to comply to the
current rule, let's create a specific option for the timer8 and select it
from the arch's Kconfig.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

In order to compile on all arch without error with 'allyesconfig' make
sure the platform selected the GENERIC_CLOCKEVENTS. Without this patch
the new added drivers will prevent the kernel to compile on PARISC.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Let the platform's Kconfig to select the clock instead of having a reverse
dependency from the driver to the platform options.

Add the COMPILE_TEST option for the compilation test coverage. Due to the
non portable 'delay' code, this driver is only compilable on ARM.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NChanwoo Choi <cw00.choi@samsung.com>

Let the platform's Kconfig to select the clock instead of having a reverse
dependency from the driver to the platform options.

Add the COMPILE_TEST option for the compilation test coverage.

This change is debatable as the option itself in the Kconfig allows to
select the driver for the platform or not. This change will make the prcmu
timer always selected.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.

Due to the non portable code for the delay timer, this option is only
available for the ARM architecture.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.

The driver depends on the common clock framework, thus the dependency added
on COMMON_CLK.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>

Increase the compilation test coverage by adding the COMPILE_TEST option.

Due to the non portable code for the delay timer, this option is only
available for the ARM architecture.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>