diff options
| author | Grygorii Strashko <grygorii.strashko@ti.com> | 2015-11-30 21:25:12 +0300 |
|---|---|---|
| committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2015-12-16 11:58:47 +0300 |
| commit | 9c9ae5ffee2831c0b8c0b002443b093e141d08f1 (patch) | |
| tree | 303b3805c05f09417d0653f8e6ecd993f97844ac | |
| parent | 272a25a247ce6d31315856721014635469500e96 (diff) | |
| download | linux-9c9ae5ffee2831c0b8c0b002443b093e141d08f1.tar.xz | |
clocksource/drivers/arm_global_timer: Fix suspend resume
Now the System stall is observed on TI AM437x based board (am437x-gp-evm)
during resuming from System suspend when ARM Global timer is selected as
clocksource device (CPUIdle not enabled) - SysRq are working, but nothing
else.
The reason of stall is that ARM Global timer loses its contexts during
System suspend:
GT_CONTROL.TIMER_ENABLE = 0 (unbanked)
GT_COUNTERx = 0
Hence, update ARM Global timer driver to reflect above behaviour
- re-enable ARM Global timer on resume (GT_CONTROL.TIMER_ENABLE = 1)
if not enabled.
CC: Arnd Bergmann <arnd@arndb.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
| -rw-r--r-- | drivers/clocksource/arm_global_timer.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c index f99be6bafad1..d189d8cb69f7 100644 --- a/drivers/clocksource/arm_global_timer.c +++ b/drivers/clocksource/arm_global_timer.c @@ -195,12 +195,23 @@ static cycle_t gt_clocksource_read(struct clocksource *cs) return gt_counter_read(); } +static void gt_resume(struct clocksource *cs) +{ + unsigned long ctrl; + + ctrl = readl(gt_base + GT_CONTROL); + if (!(ctrl & GT_CONTROL_TIMER_ENABLE)) + /* re-enable timer on resume */ + writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL); +} + static struct clocksource gt_clocksource = { .name = "arm_global_timer", .rating = 300, .read = gt_clocksource_read, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .resume = gt_resume, }; #ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK |