On 3/22/21 9:18 AM, Daniel Lezcano wrote: > On 22/03/2021 05:47, Samuel Holland wrote: >> In preparation for adding CPU idle states, hook up the sun4i timer. >> Having a non-c3stop clockevent source available is necessary for all >> CPUs to simultaneously enter a local-timer-stop idle state. > > Why simultaneously ? Because the CPU providing (the hrtimer providing) the broadcast timer cannot enter an idle state which would stop that timer. So in my case, with 4 CPUs, I was seeing at most 3 CPUs enter idle at any given time. This prevented any cluster-level idle states from doing anything. After applying this series, I was able to observe the whole cluster powering down when appropriate. Regards, Samuel >> Changes from v1: >> - Removed H616 changes (depends on an unmerged patch set) >> - Reworded the patch 4-5 commit messages for clarity >> - Added Acked-by tags >> >> Samuel Holland (5): >> dt-bindings: timer: Simplify conditional expressions >> dt-bindings: timer: Add compatibles for sun50i timers >> arm64: dts: allwinner: a64: Sort watchdog node >> arm64: dts: allwinner: Add sun4i MMIO timer nodes >> arm64: sunxi: Build the sun4i timer driver >> >> .../timer/allwinner,sun4i-a10-timer.yaml | 42 +++++++++---------- >> arch/arm64/Kconfig.platforms | 1 + >> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 25 +++++++---- >> arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 9 ++++ >> 4 files changed, 46 insertions(+), 31 deletions(-) >> > >
