[PATCH v5 3/8] ARM: dts: rockchip: add timer entries to rk3188 SoC
From: Alexander Kochetkov <hidden>
Date: 2017-01-30 13:13:31
Also in:
linux-devicetree, linux-rockchip, lkml
30 ???. 2017 ?., ? 15:04, Daniel Lezcano [off-list ref] ???????(?): There is no case when the rockchip timer is used for the clockevent.
The is already timer entry for rk3228 in the DT. And it act as clockevent. I guess it work as backup, but I cannot test it also. In order to not break DT compatibility I had to provide one timer to be initialized as clockevent. And implemented implicit rule the driver (first DT timer - clockevent, second DT timer - clocksource) already exists for other timers.
If I'm not wrong, you can check /proc/interrupts and see there is no interrupt on the rockchip timer.
Yes, you right here. I?ve temporary disable smp_twd to test rockchip timer interrupts. There is no interrupt on the rockchip timer during normal work.
- when the CPU enters a deep idle state. But such state does not exist on rk3188
ARM chip/revision specific?
- when the system goes to suspend. But the timers are stopped in any case and CPU0 is always on.
There is timer for rk3228 in the DT. I guess there are situations where it can be used. May be the situations are also acceptable for rk3188? May be something like suspend to RAM or suspend to HDD? I am not expert in that questions. I can do some tests if you give hint/link. So, as I understood you suggest to leave only one timer what can be used as clocksource only. I can implement that, but there should be DT rule what allow to setup timer as clocksource only. I cannot do more without timer framework support. Looks, like I have to wait your patch to implement that. Alexander.