Re: [PATCH v6 05/13] drm/xe/hwmon: Handle unavailable memory controller sensors

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Fri, Sep 25, 2026 at 02:24:21AM +0530, Karthik Poosa wrote:
> Skip memory controller sensors that report invalid readings when
> computing the average temperature in get_mc_temp(). Return -ENXIO when
> no valid sensor data is available, and allow the helper to be used as
> an availability probe by making the output parameter optional.
> 
> Signed-off-by: Karthik Poosa <karthik.poosa@intel.com>
> Fixes: 3a0cb885e111 ("drm/xe/hwmon: Expose memory controller temperature")

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> ---
>  drivers/gpu/drm/xe/xe_hwmon.c | 20 ++++++++++++++++----
>  1 file changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
> index 8a1dbe708828..83466b8d8d27 100644
> --- a/drivers/gpu/drm/xe/xe_hwmon.c
> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
> @@ -849,8 +849,8 @@ static int mbx_temp_decode(u8 value)
>  static int get_mc_temp(struct xe_hwmon *hwmon, long *val)
>  {
>  	struct xe_tile *root_tile = xe_device_get_root_tile(hwmon->xe);
> +	int ret, i, count = 0;
>  	s32 average = 0;
> -	int ret, i;
>  
>  	for (i = 0; i < DIV_ROUND_UP(hwmon->temp.count, sizeof(u32)); i++) {
>  		ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_THERMAL_INFO, READ_THERMAL_DATA, i),
> @@ -861,11 +861,23 @@ static int get_mc_temp(struct xe_hwmon *hwmon, long *val)
>  			hwmon->temp.dword[i]);
>  	}
>  
> -	for (i = TEMP_INDEX_MCTRL; i < hwmon->temp.count - 1; i++)
> +	for (i = TEMP_INDEX_MCTRL; i < hwmon->temp.count - 1; i++) {
> +		if (!mbx_temp_valid(hwmon, hwmon->temp.value[i]))
> +			continue;
>  		average += mbx_temp_decode(hwmon->temp.value[i]);
> +		count++;
> +	}
> +
> +	if (!count) {
> +		drm_dbg(&hwmon->xe->drm, "Memory controller temperature unavailable!\n");
> +		return -ENXIO;
> +	}
> +
> +	average /= count;
> +
> +	if (val)
> +		*val = average * MILLIDEGREE_PER_DEGREE;
>  
> -	average /= (hwmon->temp.count - TEMP_INDEX_MCTRL - 1);
> -	*val = average * MILLIDEGREE_PER_DEGREE;
>  	return 0;
>  }
>  
> -- 
> 2.25.1
>