The linux kernel relies on the RTC reporting pending interrupts if
the RTC alarm was used to wake the system. If we clear these flags
here then the rtc-cmos driver in the kernel will think that no
interrupts are pending and will not re-start the timerqueue to
handle the alarm timerqueue node.
This flag doesn't exist in SMM but the rtc code is compiled there.
Since rtc_init() is not called by SMM it is guarded with an ifdef.
I performed several thousand suspend/resume cycles without seeing
an issue where hwclock was unable to read from /dev/rtc. There
still is a potential kernel issue where the timerqueue can stall
but this makes that much less likely to happen on resume.
Change-Id: I5a343da4ce5c4c8ec4783b4e503869ccfa5077f0
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/1741
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
4b1610d766