Re: [PATCH v12 13/16] drm/xe/hwmon: add PCIe temperature support for CRI

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] hwmon: pcie_temp_index() uses strict equality for CRI unlike get_mc_temp()
--

commit 4122768dbcd48bfed72f1531064229c2807857fd
Author: Karthik Poosa <karthik.poosa@intel.com>

drm/xe/hwmon: add PCIe temperature support for CRI

This commit adds the PCIe temperature sensor offset in READ_THERMAL_DATA for
the Crescent Island (CRI) platform. It refactors PCIe temperature handling to
use platform-specific sensor indices rather than special-case decoding logic.

> diff --git a/drivers/gpu/drm/xe/xe_hwmon.c b/drivers/gpu/drm/xe/xe_hwmon.c
> index bccae2ea91fdb..3c1f6b70c82dc 100644
> --- a/drivers/gpu/drm/xe/xe_hwmon.c
> +++ b/drivers/gpu/drm/xe/xe_hwmon.c
[ ... ]
> @@ -1016,21 +1019,30 @@ static int get_mc_temp(struct xe_hwmon *hwmon, long *val)
>  	return 0;
>  }
>  
> -static int get_pcie_temp(struct xe_hwmon *hwmon, long *val)
> +static u8 xe_hwmon_pcie_temp_index(const struct xe_hwmon *hwmon)
> +{
> +	if (hwmon->xe->info.platform == XE_CRESCENTISLAND)
> +		return CRI_TEMP_INDEX_PCIE;

[Severity: Medium]
Will this strict equality check cause incorrect PCIe temperature readings on
future platforms that inherit this mailbox layout? 

In get_mc_temp(), the driver uses a greater-than-or-equal comparison for the
same platform:

	if (hwmon->xe->info.platform >= XE_CRESCENTISLAND) {
		start = CRI_TEMP_INDEX_MCTRL;

Does xe_hwmon_pcie_temp_index() need to use >= XE_CRESCENTISLAND to match
the behavior of get_mc_temp() and correctly support future platforms?

> +
> +	if (hwmon->xe->info.subplatform == XE_SUBPLATFORM_BATTLEMAGE_G21)
> +		return BMG_G21_TEMP_INDEX_PCIE;
> +
> +	return TEMP_INDEX_PCIE;
> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261013184939.694945-1-karthik.poosa@intel.com?part=13