Re: [PATCH] drm/amd/pm: avoid driver getting empty metrics table for the first time

["Lazar, Lijo" <lijo.lazar@xxxxxxx>]

On 8/4/2023 8:02 PM, Yang Wang wrote:
> From: Yang Wang <KevinYang.Wang@xxxxxxx>
>
> add metrics.AccumulationCouter check to avoid driver getting an empty
> metrics data since metrics table not updated completely in pmfw side.
>
> Signed-off-by: Yang Wang <KevinYang.Wang@xxxxxxx>
> Reviewed-by: Asad Kamal <asad.kamal@xxxxxxx>
> Tested-by: Asad Kamal <asad.kamal@xxxxxxx>

Reviewed-by: Lijo Lazar <lijo.lazar@xxxxxxx>

Thanks,
Lijo

> ---
>   .../drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c  | 20 ++++++++++++++-----
>   1 file changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c
> index 6253ad13833c..5adc6b92bc49 100644
> --- a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c
> +++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0_6_ppt.c
> @@ -325,14 +325,24 @@ static int smu_v13_0_6_setup_driver_pptable(struct smu_context *smu)
>   	MetricsTable_t *metrics = (MetricsTable_t *)smu_table->metrics_table;
>   	struct PPTable_t *pptable =
>   		(struct PPTable_t *)smu_table->driver_pptable;
> -	int ret;
> -	int i;
> +	int ret, i, retry = 100;
>   
>   	/* Store one-time values in driver PPTable */
>   	if (!pptable->Init) {
> -		ret = smu_v13_0_6_get_metrics_table(smu, NULL, false);
> -		if (ret)
> -			return ret;
> +		while (retry--) {
> +			ret = smu_v13_0_6_get_metrics_table(smu, NULL, true);
> +			if (ret)
> +				return ret;
> +
> +			/* Ensure that metrics have been updated */
> +			if (metrics->AccumulationCounter)
> +				break;
> +
> +			msleep(1);
> +		}
> +
> +		if (!retry)
> +			return -ETIME;
>   
>   		pptable->MaxSocketPowerLimit =
>   			SMUQ10_TO_UINT(metrics->MaxSocketPowerLimit);