Re: [PATCH v2 2/2] cpufreq: mediatek-hw: Wait for CPU supplies before probing

From: AngeloGioacchino Del Regno
Date: Wed Jan 10 2024 - 09:31:42 EST


Il 10/01/24 15:23, Nícolas F. R. A. Prado ha scritto:
Before proceeding with the probe and enabling frequency scaling for the
CPUs, make sure that all supplies feeding the CPUs have probed.

This fixes an issue observed on MT8195-Tomato where if the
mediatek-cpufreq-hw driver enabled the hardware (by writing to
REG_FREQ_ENABLE) before the SPMI controller driver (spmi-mtk-pmif),
behind which lies the big CPU supply, probed the platform would hang
shortly after with "rcu: INFO: rcu_preempt detected stalls on
CPUs/tasks" being printed in the log.

Fixes: 4855e26bcf4d ("cpufreq: mediatek-hw: Add support for CPUFREQ HW")
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>


Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>