Re: [PATCH v2 4/7] drm/xe/hwmon: Read thermal sensors count

["Poosa, Karthik" <karthik.poosa@intel.com>]

On 11-12-2025 22:58, Nilawar, Badal wrote:
>
> On 10-12-2025 11:52, Karthik Poosa wrote:
>> Read number of thermal sensors available.
>>
>> Signed-off-by: Karthik Poosa <karthik.poosa@intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_hwmon.c | 28 ++++++++++++++++++++++++----
>>   1 file changed, 24 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c 
>> b/drivers/gpu/drm/xe/xe_hwmon.c
>> index c4a200cc2c23..e843021d13ec 100644
>> --- a/drivers/gpu/drm/xe/xe_hwmon.c
>> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
>> @@ -99,6 +99,11 @@ enum sensor_attr_power {
>>    */
>>   #define PL_WRITE_MBX_TIMEOUT_MS    (1)
>>   +/*
>> + * Number of thermal sensors.
>> + */
>> +#define MAX_THERMAL_SENSORS    (11)
>> +
>>   /**
>>    * struct xe_hwmon_energy_info - to accumulate energy
>>    */
>> @@ -126,9 +131,11 @@ struct xe_hwmon_thermal_info {
>>       union {
>>           /** @limits: temperatures limits */
>>           u8 limit[8];
>> -        /** @data: limits data dwords */
>> -        u32 data[2];
>> +        /** @dword: limit dwords */
>> +        u32 dword[2];
> Please maintain variable name consistent throughout the series.
>>       };
>> +    /** @count: no of temperature sensors */
>> +    u8 count;
>>   };
>>     /**
>> @@ -716,18 +723,31 @@ static int 
>> xe_hwmon_pcode_read_thermal_info(struct xe_hwmon *hwmon)
>>   {
>>       struct xe_tile *root_tile = xe_device_get_root_tile(hwmon->xe);
>>       int ret = 0;
>> +    u32 val = 0;
>>         if (!hwmon->xe->info.has_mbx_power_limits)
>>           return -ENXIO;
>>         /* Read thermal info */
>>       ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_THERMAL_INFO, 
>> READ_THERMAL_LIMITS, 0),
>> -                &hwmon->temp.data[0], &hwmon->temp.data[1]);
>> +                &hwmon->temp.dword[0], &hwmon->temp.dword[1]);
>>       drm_dbg(&hwmon->xe->drm, "thermal info read ret %d, val 0x%x 
>> val1 0x%x\n", ret,
>> -        hwmon->temp.data[0], hwmon->temp.data[1]);
>> +        hwmon->temp.dword[0], hwmon->temp.dword[1]);
>>       if (ret)
>>           return ret;
>>   +    /* Read thermal config */
>> +    ret = xe_pcode_read(root_tile, PCODE_MBOX(PCODE_THERMAL_INFO, 
>> READ_THERMAL_CONFIG, 0),
>> +                &val, NULL);
>> +    drm_dbg(&hwmon->xe->drm, "thermal config read ret %d, count 
>> %d\n", ret, val);
>> +    if (ret)
>> +        return ret;
>> +
>> +    hwmon->temp.count = val & TEMP_MASK;
>> +    if (hwmon->temp.count > MAX_THERMAL_SENSORS)
>
> Why this restriction?

Because we created the structure to hold sensor data of 
MAX_THERMAL_SENSORS only.

I think we can increase MAX_THERMAL_SENSORS to 255 as that is max count 
supported by thermal mailbox.

>> + drm_warn(&hwmon->xe->drm, "thermal config count %d exceeds 
>> supported limit %d\n",
>> +             hwmon->temp.count, MAX_THERMAL_SENSORS);
>> +
>>       return 0;
> I am seeing patch 5 is exposing avj of hwmon->temp.count sensors, so 
> could you please combine patch 4 and 5.
>
> Thanks,
> Badal
>
>>   }