| Message ID | 1448653624-25006-1-git-send-email-grygorii.strashko@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 11/27/15 11:47 AM, Grygorii Strashko wrote: > 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. > > 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: Santosh Shilimkar <ssantosh@kernel.org> > Cc: Marc Zyngier <marc.zyngier@arm.com> > Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> > --- > Changes in v3: > - dropped all DT specific code > Changes in v2: > - suspend/resume simplified: nothing is stored any more and > ARM GT just re-enabled > Link on v2: > https://lkml.org/lkml/2015/11/20/355 > Link on v1: > https://lkml.org/lkml/2015/11/13/456 > Looks reasonable to me. > drivers/clocksource/arm_global_timer.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c > index a2cb6fa..10d1417 100644 > --- a/drivers/clocksource/arm_global_timer.c > +++ b/drivers/clocksource/arm_global_timer.c > @@ -195,12 +195,19 @@ static cycle_t gt_clocksource_read(struct clocksource *cs) > return gt_counter_read(); > } > > +static void gt_resume(struct clocksource *cs) > +{ > + /* re-enable timer on resume */ > + writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL); Check if its disabled before enabling it. Other than that, Reviewed-by: Santosh Shilimkar <ssantosh@kernel.org>
On 11/30/2015 02:29 AM, santosh.shilimkar@oracle.com wrote: > On 11/27/15 11:47 AM, Grygorii Strashko wrote: >> 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. >> >> 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: Santosh Shilimkar <ssantosh@kernel.org> >> Cc: Marc Zyngier <marc.zyngier@arm.com> >> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> >> --- >> Changes in v3: >> - dropped all DT specific code >> Changes in v2: >> - suspend/resume simplified: nothing is stored any more and >> ARM GT just re-enabled >> Link on v2: >> https://lkml.org/lkml/2015/11/20/355 >> Link on v1: >> https://lkml.org/lkml/2015/11/13/456 >> > Looks reasonable to me. >> drivers/clocksource/arm_global_timer.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/drivers/clocksource/arm_global_timer.c >> b/drivers/clocksource/arm_global_timer.c >> index a2cb6fa..10d1417 100644 >> --- a/drivers/clocksource/arm_global_timer.c >> +++ b/drivers/clocksource/arm_global_timer.c >> @@ -195,12 +195,19 @@ static cycle_t gt_clocksource_read(struct >> clocksource *cs) >> return gt_counter_read(); >> } >> >> +static void gt_resume(struct clocksource *cs) >> +{ >> + /* re-enable timer on resume */ >> + writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL); > > Check if its disabled before enabling it. > Other than that, > Reviewed-by: Santosh Shilimkar <ssantosh@kernel.org> Sure, I'll update. Thanks.
diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c index a2cb6fa..10d1417 100644 --- a/drivers/clocksource/arm_global_timer.c +++ b/drivers/clocksource/arm_global_timer.c @@ -195,12 +195,19 @@ static cycle_t gt_clocksource_read(struct clocksource *cs) return gt_counter_read(); } +static void gt_resume(struct clocksource *cs) +{ + /* 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
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. 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: Santosh Shilimkar <ssantosh@kernel.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> --- Changes in v3: - dropped all DT specific code Changes in v2: - suspend/resume simplified: nothing is stored any more and ARM GT just re-enabled Link on v2: https://lkml.org/lkml/2015/11/20/355 Link on v1: https://lkml.org/lkml/2015/11/13/456 drivers/clocksource/arm_global_timer.c | 7 +++++++ 1 file changed, 7 insertions(+)