linux-toradex.git/drivers/clocksource/timer-sun5i.c, branch v4.9.16

Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"

2016-10-20T19:58:58+00:00

struct clocksource is also used by the clk notifier callback, to
unregister and re-register the clocksource with a different clock rate.
clocksource_mmio_init does not pass back a pointer to the struct used,
and the clk notifier callback assumes that the struct clocksource in
struct sun5i_timer_clksrc is valid. This results in a kernel NULL
pointer dereference when the hstimer clock is changed:

Unable to handle kernel NULL pointer dereference at virtual address 00000004
[] (clocksource_unbind) from [] (clocksource_unregister+0x2c/0x44)
[] (clocksource_unregister) from [] (sun5i_rate_cb_clksrc+0x34/0x3c)
[] (sun5i_rate_cb_clksrc) from [] (notifier_call_chain+0x44/0x84)
[] (notifier_call_chain) from [] (__srcu_notifier_call_chain+0x44/0x60)
[] (__srcu_notifier_call_chain) from [] (srcu_notifier_call_chain+0x18/0x20)
[] (srcu_notifier_call_chain) from [] (__clk_notify+0x70/0x7c)
[] (__clk_notify) from [] (clk_propagate_rate_change+0xa4/0xc4)
[] (clk_propagate_rate_change) from [] (clk_propagate_rate_change+0x6c/0xc4)

Revert the commit for now. clocksource_mmio_init can be made to pass back
a pointer, but the code churn and usage of an inner struct might not be
worth it.

Fixes: 157dfadef832 ("clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init")
Reported-by: Maxime Ripard 
Signed-off-by: Chen-Yu Tsai 
Cc: linux-sunxi@googlegroups.com
Cc: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20161018054918.26855-1-wens@csie.org
Signed-off-by: Thomas Gleixner

clocksources: Switch back to the clksrc table

2016-06-28T08:19:35+00:00

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 

For exynos_mct and samsung_pwm_timer:
Acked-by: Krzysztof Kozlowski 

For arch/arc:
Acked-by: Vineet Gupta 

For mediatek driver:
Acked-by: Matthias Brugger 

For the Rockchip-part
Acked-by: Heiko Stuebner 

For STi :
Acked-by: Patrice Chotard 

For the mps2-timer.c and versatile.c changes:
Acked-by: Liviu Dudau 

For the OXNAS part :
Acked-by: Neil Armstrong 

For LPC32xx driver:
Acked-by: Sylvain Lemieux 

For Broadcom Kona timer change:
Acked-by: Ray Jui 

For Sun4i and Sun5i:
Acked-by: Chen-Yu Tsai 

For Meson6:
Acked-by: Carlo Caione 

For Keystone:
Acked-by: Santosh Shilimkar 

For NPS:
Acked-by: Noam Camus 

For bcm2835:
Acked-by: Eric Anholt

clocksource/drivers/sun5i: Convert init function to return error

2016-06-28T08:19:31+00:00

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

clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init

2015-12-15T08:42:30+00:00

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

The only difference is the readl vs readl_relaxed.

Factor out the code with the clocksource_mmio_init function.

Signed-off-by: Daniel Lezcano 
Acked-by: Maxime Ripard

clockevents/drivers/sun5i: Migrate to new 'set-state' interface

2015-08-10T09:40:49+00:00

Migrate sun5i 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 
Signed-off-by: Viresh Kumar 
Signed-off-by: Daniel Lezcano 
Acked-by: Maxime Ripard

clocksource: sun5i: Fix of_io_request_and_map error check

2015-05-05T08:35:58+00:00

of_io_request_and map returns an error pointer, but the current code assumes
that on error the returned pointer will be NULL.

Obviously, that makes the check completely useless. Change the test to actually
check for the proper error code.

Signed-off-by: Maxime Ripard 
Cc: Daniel Lezcano 
Link: http://lkml.kernel.org/r/1430579006-32702-6-git-send-email-maxime.ripard@free-electrons.com
Signed-off-by: Thomas Gleixner

clocksource/drivers/sun5i: Add clock notifiers

2015-03-31T15:53:58+00:00

The parent clock of the sun5i timer is the AHB clock, which rate
might change because of other devices requirements.

This is for example the case on the Allwinner A31, where the DMA
controller needs a minimum rate higher than the default, that is
enforced after the timer driver has probed.

Add clock notifiers to make sure we reflect the clock rate
changes in the timer rates.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1427796746-373-5-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar

clocksource/drivers/sun5i: Refactor the current code

2015-03-31T15:53:58+00:00

Refactor the code in order to remove the global variables and
split the clock source and clock events registration in order to
ease the addition of the clock notifiers needed to handle the
parent clock rate changes.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1427796746-373-4-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar

clocksource/drivers/sun5i: Use of_io_request_and_map()

2015-03-31T15:53:58+00:00

of_iomap doesn't do a request_mem_region() on the memory area
defined in the DT it maps. Switch to of_io_request_and_map() to
make sure we're the only users.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1427796746-373-3-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar

clocksource/drivers/sun5i: Switch to request_irq()

2015-03-31T15:53:57+00:00

The current code uses setup_irq(), while it could perfectly use
the much simpler request_irq(). Switch to that.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1427796746-373-2-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar