Re: [PATCH v3 23/47] clk: qcom: gcc-sm6350: Tie the CX power domain to controller

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The GCC controller will never enter runtime suspend, preventing the CX power domain from powering down at runtime as intended due to critical clocks.
--

--- Patch [23]: [PATCH v3 23/47] clk: qcom: gcc-sm6350: Tie the CX power domain to controller ---
commit 5be3761ba3c42a260ccac2e7a6451b101d998dad
Author: Abel Vesa <abel.vesa@oss.qualcomm.com>

clk: qcom: gcc-sm6350: Tie the CX power domain to controller

This commit sets use_rpm = true in the gcc_sm6350_desc struct to enable
runtime PM for the GCC controller. The stated intent is to allow the CX
power domain to be powered down once all consumers have released their
clocks and GDSCs.

> diff --git a/drivers/clk/qcom/gcc-sm6350.c b/drivers/clk/qcom/gcc-sm6350.c
> index a4d6dff9d0f7f..b99a5bc530483 100644
> --- a/drivers/clk/qcom/gcc-sm6350.c
> +++ b/drivers/clk/qcom/gcc-sm6350.c
> @@ -2545,6 +2545,7 @@ static const struct qcom_cc_desc gcc_sm6350_desc = {
>  	.num_resets = ARRAY_SIZE(gcc_sm6350_resets),
>  	.gdscs = gcc_sm6350_gdscs,
>  	.num_gdscs = ARRAY_SIZE(gcc_sm6350_gdscs),
> +	.use_rpm = true,

[Severity: Medium]
Will this actually allow the GCC controller to enter runtime suspend?

Looking at drivers/clk/qcom/gcc-sm6350.c, there are multiple clocks
registered with the CLK_IS_CRITICAL flag, such as gcc_camera_ahb_clk.

When use_rpm is set to true, the clock core takes a runtime PM reference on
the GCC device during clock preparation. Since critical clocks are prepared
during initialization and never unprepared, their runtime PM references are
never dropped.

Won't the usage counter permanently stay above zero, preventing the CX power
domain from ever powering down?

>  };
>  
>  static const struct of_device_id gcc_sm6350_match_table[] = {

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260824-qcom-tie-cx-to-gcc-v3-0-f1205a92682b@oss.qualcomm.com?part=23