Commit Graph

19 Commits

Author SHA1 Message Date
Thomas Gleixner
af873fcece treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194
Based on 1 normalized pattern(s):

  license terms gnu general public license gpl version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 161 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.447718015@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:22 -07:00
Julia Lawall
a26ed66c20 clocksource/drivers/stm32: Fix error return code
Return an error code on failure.

Problem found using Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: kernel-janitors@vger.kernel.org
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lkml.kernel.org/r1528640655-18948-3-git-send-email-Julia.Lawall@lip6.fr
2018-06-12 23:54:01 +02:00
Daniel Lezcano
103bb56a28 clocksource/drivers/stm32: Start the timer's counter sooner
As we have a lot of timers on this platform, we can have potentially all the
timers enabled in the DT, so we don't want to start the timer for every probe
otherwise they will be running for nothing as only one will be used.

Start the timer only when setting the mode or when the clocksource is
enabled.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-20-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:26 +01:00
Daniel Lezcano
81abdbbffd clocksource/drivers/stm32: Add the timer delay callback
Add the timer delay callback, that saves us ~90ms of boot time.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-19-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:26 +01:00
Benjamin Gaignard
f5ef02bd0e clocksource/drivers/stm32: Add clocksource functionality
The scene is set for the clocksource functionality, let's add it for this driver.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-18-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:26 +01:00
Daniel Lezcano
3c84e75b1e clocksource/drivers/stm32: Factor out more of the clockevent code
In order to prepare the clocksource code, let's factor out the clockevent
code, split the prescaler and timer width code into separate functions.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-17-git-send-email-daniel.lezcano@linaro.org
[ Small edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:26 +01:00
Benjamin Gaignard
8e82df381b clocksource/drivers/stm32: Add oneshot mode
The stm32 timer block is able to have a counter and a comparator.

Instead of using the auto-reload register for periodic events, we switch
to oneshot mode by using the comparator register.

The timer is able to generate an interrupt when the counter overflows but
we don't want that as this counter will be use as a clocksource in the next
patches. So it is disabled by the UDIS bit of the control register.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-16-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:26 +01:00
Benjamin Gaignard
4744daa10d clocksource/drivers/stm32: Compute a prescaler value with a targeted rate
The prescaler value is arbitrarily set to 1024 without any regard to the
timer frequency. For 32-bit timers, there is no need to set a prescaler
value as they wrap in an acceptable interval and give the opportunity to
have precise timers on this platform. However, for 16-bit timers a prescaler
value is needed if we don't want to wrap too often per second which is
inefficient and adds more and more error margin. With a targeted clock
of 10MHz, the 16 bits are precise enough whatever the timer frequency is
as we will compute the prescaler.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-15-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
Daniel Lezcano
70c62cf910 clocksource/drivers/stm32: Factor out the timer width sorting code
In order to clarify and encapsulate the code for upcoming changes, move the
timer width check into a function and add some documentation.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-14-git-send-email-daniel.lezcano@linaro.org
[ Spelling fixes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
Daniel Lezcano
f2ed8ef1ce clocksource/drivers/stm32: Use the node name as timer name
As there are different timers on the stm32, use the node name for the timer
name in order to give the indication of which timer the kernel is using.

/proc/timer_list gives all the information with the right name, otherwise
we end up digging in the kernel log and /proc/interrupt to do the connection
between the used timer.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-13-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
Benjamin Gaignard
d04af4908a clocksource/drivers/stm32: Convert the driver to timer_of primitives
Convert the driver to use the timer_of() helpers. This allows the removal of
a custom private structure, factors out and simplifies the code.

[Daniel Lezcano]: Respin against the critical fix patch and massaged the changelog.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1515418139-23276-12-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
Daniel Lezcano
e0aeca3d8c clocksource/drivers/stm32: Fix kernel panic with multiple timers
The current code hides a couple of bugs:

 - The global variable 'clock_event_ddata' is overwritten each time the
   init function is invoked.

This is fixed with a kmemdup() instead of assigning the global variable. That
prevents a memory corruption when several timers are defined in the DT.

 - The clockevent's event_handler is NULL if the time framework does
   not select the clockevent when registering it, this is fine but the init
   code generates in any case an interrupt leading to dereference this
   NULL pointer.

The stm32 timer works with shadow registers, a mechanism to cache the
registers. When a change is done in one buffered register, we need to
artificially generate an event to force the timer to copy the content
of the register to the shadowed register.

The auto-reload register (ARR) is one of the shadowed register as well as
the prescaler register (PSC), so in order to force the copy, we issue an
event which in turn leads to an interrupt and the NULL dereference.

This is fixed by inverting two lines where we clear the status register
before enabling the update event interrupt.

As this kernel crash is resulting from the combination of these two bugs,
the fixes are grouped into a single patch.

Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1515418139-23276-11-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08 17:57:25 +01:00
Rob Herring
469869d18a clocksource: Convert to using %pOF instead of full_name
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Acked-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-08-31 15:56:17 +02:00
Daniel Lezcano
1727339590 clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the
clocksource at early stage. However, this macro is also used to initialize
the clockevent if any, or the clockevent only.

It was originally suggested to declare another macro to initialize a
clockevent, so in order to separate the two entities even they belong to the
same IP. This was not accepted because of the impact on the DT where splitting
a clocksource/clockevent definition does not make sense as it is a Linux
concept not a hardware description.

On the other side, the clocksource has not interrupt declared while the
clockevent has, so it is easy from the driver to know if the description is
for a clockevent or a clocksource, IOW it could be implemented at the driver
level.

So instead of dealing with a named clocksource macro, let's use a more generic
one: TIMER_OF_DECLARE.

The patch has not functional changes.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14 11:58:45 +02:00
Daniel Lezcano
177cf6e52b clocksources: Switch back to the clksrc table
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>
2016-06-28 10:19:35 +02:00
Daniel Lezcano
38d94c5ae2 clocksource/drivers/stm32: Convert init function to return error
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>
Acked-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
2016-06-28 10:19:31 +02:00
Viresh Kumar
8e8af4cd3b clockevents/drivers/stm32: Migrate to new 'set-state' interface
Migrate stm32 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 Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Acked-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
2015-08-10 11:40:48 +02:00
Maxime Coquelin
d4688bdc63 clockevents/drivers/timer-stm32: Fix build warning spotted by kbuild test robot
This patch fixes below warning spotted by kbuild test robot when building
with ARCH=powerpc:

   drivers/clocksource/timer-stm32.c: In function 'stm32_clockevent_init':
>> drivers/clocksource/timer-stm32.c:140:9: warning: large integer implicitly
	truncated to unsigned type [-Woverflow]

     writel_relaxed(~0UL, data->base + TIM_ARR);

The fix consists in using 0U instead of 0UL.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02 12:10:16 +02:00
Maxime Coquelin
e37e45934a clockevents/drivers: Add STM32 Timer driver
STM32 MCUs feature 16 and 32 bits general purpose timers with prescalers.
The drivers detects whether the time is 16 or 32 bits, and applies a
1024 prescaler value if it is 16 bits.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-06-02 12:10:15 +02:00