Re: [PATCH v2 1/5] platform/x86/amd/pmc: Check for intermediate wakeup in function

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Sat, 9 May 2026, Daniel Gibson wrote:

> This slightly refactors code introduced by the

Avoid starting changelog with "This" or "This patch" but use imperative 
tone instead. You can start with "Refactor code ..."

> "pmc: Require at least 2.5 seconds between HW sleep cycles"

Please always use the canonical commit reference format (see 
Documentation/process/submitting-patches.rst for detail).

It's on the borderline if the origin of the code even matters that much 
but since you're adding the (nice) comment, I guess it is easier to figure 
out where that came from by having the reference in place.

> commit
> to allow adding different conditions for that delay later.

later -> in an upcoming change

> 
> References: 9f5595d5f03f ("platform/x86/amd: pmc: Require at least 2.5 seconds between HW sleep cycles")

Drop this.

> Signed-off-by: Daniel Gibson <daniel@gibson.sh>
> ---
>  drivers/platform/x86/amd/pmc/pmc.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
> index cae3fcafd4d7..2b9e5730170a 100644
> --- a/drivers/platform/x86/amd/pmc/pmc.c
> +++ b/drivers/platform/x86/amd/pmc/pmc.c
> @@ -598,6 +598,19 @@ static int amd_pmc_verify_czn_rtc(struct amd_pmc_dev *pdev, u32 *arg)
>  	return rc;
>  }
>  
> +static bool amd_pmc_intermediate_wakeup_need_delay(struct amd_pmc_dev *pdev)
> +{
> +	/*
> +	 * Starting a new HW sleep cycle right after waking from one
> +	 * can cause electrical problems triggering the over voltage protection.
> +	 * That is avoided by delaying the next suspend a bit, see also
> +	 * https://lore.kernel.org/all/20250414162446.3853194-1-superm1@kernel.org/
> +	 */
> +	struct smu_metrics table;
> +
> +	return get_metrics_table(pdev, &table) == 0 && table.s0i3_last_entry_status;
> +}
> +
>  static void amd_pmc_s2idle_prepare(void)
>  {
>  	struct amd_pmc_dev *pdev = &pmc;
> @@ -632,11 +645,9 @@ static void amd_pmc_s2idle_prepare(void)
>  static void amd_pmc_s2idle_check(void)
>  {
>  	struct amd_pmc_dev *pdev = &pmc;
> -	struct smu_metrics table;
>  	int rc;
>  
> -	/* Avoid triggering OVP */
> -	if (!get_metrics_table(pdev, &table) && table.s0i3_last_entry_status)
> +	if (amd_pmc_intermediate_wakeup_need_delay(pdev))
>  		msleep(2500);
>  
>  	/* Dump the IdleMask before we add to the STB */
> 

-- 
 i.