Re: [PATCH v4] clk: mediatek: Do a runtime PM get on controllers during probe

From: Stephen Boyd
Date: Wed Apr 10 2024 - 23:48:54 EST


Quoting Pin-yen Lin (2024-03-12 04:51:55)
> mt8183-mfgcfg has a mutual dependency with genpd during the probing
> stage, which leads to a deadlock in the following call stack:
>
> CPU0: genpd_lock --> clk_prepare_lock
> genpd_power_off_work_fn()
> genpd_lock()
> generic_pm_domain::power_off()
> clk_unprepare()
> clk_prepare_lock()
>
> CPU1: clk_prepare_lock --> genpd_lock
> clk_register()
> __clk_core_init()
> clk_prepare_lock()
> clk_pm_runtime_get()
> genpd_lock()
>
> Do a runtime PM get at the probe function to make sure clk_register()
> won't acquire the genpd lock. Instead of only modifying mt8183-mfgcfg,
> do this on all mediatek clock controller probings because we don't
> believe this would cause any regression.
>
> Verified on MT8183 and MT8192 Chromebooks.
>
> Fixes: acddfc2c261b ("clk: mediatek: Add MT8183 clock support")
> Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
>
> ---

Applied to clk-fixes