Re: [PATCH v2 4/4] arm64: dts: qcom: msm8917: Use a shallower cluster state to fix unresponsive idle
From: Konrad Dybcio
Date: Wed Oct 21 2026 - 06:38:41 EST
On 10/18/26 6:29 AM, Reza Kurniawan wrote:
> MSM8917 is a single cluster SoC, so powering down the cluster means
> powering down the whole system. This causes two problems:
>
> 1. The system becomes unresponsive, even to common interrupts. Waking it
> requires an interrupt from the MPM (MSM Power Manager) or scheduling
> the MPM to wake the system later. Linux currently has no way of doing
> the latter, so the cluster may never resume operation.
>
> 2. Entering power collapse blanks the screen. When the state is entered
> and exited repeatedly, this shows up as visible flicker.
>
> Even if MPM scheduling were implemented, the second problem would remain
> and it wouldn't fix the system being unresponsive at idle.
>
> Replace the idle state with PSCI mode 4 (dubbed GDHS downstream), which
> is less aggressive and can wake up from conventional interrupt sources.
>
> Signed-off-by: Reza Kurniawan <imkyufie@xxxxxxxxx>
> ---
For the sake of git bisect working, please order this patch before
patch 3.
Or alternatively, we can get rid of this one if the MPM rework
series lands first.
Konrad