| Message ID | 1369271045-17410-1-git-send-email-dbasehore@chromium.org |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, 22 May 2013 18:04:05 -0700 Derek Basehore <dbasehore@chromium.org> wrote: > During resume, we call hpet_rtc_timer_init after masking an irq bit in hpet. > This will cause the call to hpet_disable_rtc_channel to be undone if RTC_AIE is > the only bit not masked. What were the user-visible runtime effects of this bug?
I'm still debugging all of the issues, but allowing the cmos interrupt handler to run before resuming caused some issues where the timer for the alarm was not removed. This would cause other, later timers to not be cleared, so utilities such as hwclock would time out when waiting for the update interrupt. There's another patch needed that I am currently testing that works around an issue seen in coreboot (and probably other firmware) where the RTC_CONTROL register is cleared before we get to the kernel. This prevents the cmos interrupt handler from clearing an alarm. On Wed, May 29, 2013 at 12:27 PM, Andrew Morton <akpm@linux-foundation.org> wrote: > On Wed, 22 May 2013 18:04:05 -0700 Derek Basehore <dbasehore@chromium.org> wrote: > >> During resume, we call hpet_rtc_timer_init after masking an irq bit in hpet. >> This will cause the call to hpet_disable_rtc_channel to be undone if RTC_AIE is >> the only bit not masked. > > What were the user-visible runtime effects of this bug?
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index cc5bea9..ee0bc69 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -854,6 +854,10 @@ static int cmos_resume(struct device *dev) } spin_lock_irq(&rtc_lock); + if (device_may_wakeup(dev)) { + hpet_rtc_timer_init(); + } + do { CMOS_WRITE(tmp, RTC_CONTROL); hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK); @@ -869,7 +873,6 @@ static int cmos_resume(struct device *dev) rtc_update_irq(cmos->rtc, 1, mask); tmp &= ~RTC_AIE; hpet_mask_rtc_irq_bit(RTC_AIE); - hpet_rtc_timer_init(); } while (mask & RTC_AIE); spin_unlock_irq(&rtc_lock); }
During resume, we call hpet_rtc_timer_init after masking an irq bit in hpet. This will cause the call to hpet_disable_rtc_channel to be undone if RTC_AIE is the only bit not masked. Signed-off-by: Derek Basehore <dbasehore@chromium.org> --- drivers/rtc/rtc-cmos.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)