Re: [PATCH v3 12/47] clk: qcom: gcc-qcs615: 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:
- [High] The CLK_IS_CRITICAL flags on gcc_cpuss_ahb_clk and gcc_sys_noc_cpuss_ahb_clk permanently hold a runtime PM reference on the GCC controller, preventing the CX domain from ever powering down.
--

--- Patch [12]: [PATCH v3 12/47] clk: qcom: gcc-qcs615: Tie the CX power domain to controller ---
commit 4f409a8e397d7df1fcb5c05bdd3d11eaa2987e04
Author: Abel Vesa <abel.vesa@oss.qualcomm.com>

clk: qcom: gcc-qcs615: Tie the CX power domain to controller
    
Enable runtime PM for the controller, allowing CX to be powered down
once all GCC consumers have released their clocks and GDSCs.

> diff --git a/drivers/clk/qcom/gcc-qcs615.c b/drivers/clk/qcom/gcc-qcs615.c
> index 57f8c80c6f324..601c81c844505 100644
> --- a/drivers/clk/qcom/gcc-qcs615.c
> +++ b/drivers/clk/qcom/gcc-qcs615.c
> @@ -2967,6 +2967,7 @@ static const struct qcom_cc_desc gcc_qcs615_desc = {
>  	.resets = gcc_qcs615_resets,
>  	.num_resets = ARRAY_SIZE(gcc_qcs615_resets),
>  	.gdscs = gcc_qcs615_gdscs,
> +	.use_rpm = true,

[Severity: High]
The commit message states this allows CX to be powered down once all
consumers have released their clocks. Will the CX domain actually be able to
power down?

Looking at gcc_cpuss_ahb_clk and gcc_sys_noc_cpuss_ahb_clk in this driver,
they are both marked with CLK_IS_CRITICAL.

When the clock framework prepares critical clocks during initialization,
clk_core_prepare() calls clk_pm_runtime_get(), which increments the runtime PM
usage count for the GCC controller. Since critical clocks are never unprepared,
this reference is never dropped.

Will these critical clocks permanently hold the runtime PM usage count above
zero, preventing the GCC controller from ever entering runtime suspend and
keeping the CX domain powered on indefinitely?

>  	.num_gdscs = ARRAY_SIZE(gcc_qcs615_gdscs),
>  };
>

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260824-qcom-tie-cx-to-gcc-v3-0-f1205a92682b@oss.qualcomm.com?part=12