On 24/06/2019 18:34:29+0800, Chen-Yu Tsai wrote: > On Fri, Jun 21, 2019 at 12:22 AM Alexandre Belloni > <alexandre.belloni@xxxxxxxxxxx> wrote: > > > > On 04/06/2019 12:23:34+0800, Chen-Yu Tsai wrote: > > > From: Chen-Yu Tsai <wens@xxxxxxxx> > > > > > > Hi everyone, > > > > > > While bringing up my Pine H64, I encountered an interrupt storm from the > > > pcf8563 RTC. The RTC chip's interrupt line is shared with the PMIC, and > > > was not properly added to the device tree. Also, the driver was using an > > > trigger method incompatible with the PMIC, preventing the interrupt line > > > from being shared. Last, the driver only clears and masks the alarm > > > interrupt, while leaving the timer interrupt untouched. This is a > > > problem if previous systems left the timer interrupt enabled, and there > > > was an interrupt pending. > > > > > > This patch set fixes all three issues, one per patch. > > > > > > Please have a look. > > > > > > > I don't have that particular RTC so I can't test but the interrupt > > handling in pcf8563_irq seems problematic too. I guess the RTC will only > > trigger once per second because the call to pcf8563_set_alarm_mode will > > explicitely leave the alarm enabled. The core doesn't really care but it > > doesn't really expect the alarm to stay enabled. i.e. It will ensure the > > alarm is enabled again after setting it when necessary. I think it would > > be safer to simply clear both AIE and AF here. Could you test? > > Yeah, that bit looked weird to me as well. And actually the alarm doesn't > go down to the second, only the minute. > > Is there a test program I can use to test the alarms? > Sure, tools/testing/selftests/rtc/rtctest.c if you use a recent enough version, it will test minute boundaries. -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
