[Intel-gfx] [PATCH] drm/i915: Skip pxp init if gt is wedged

[Dong, Zhanjun]

On 2023-10-31 5:38 p.m., Teres Alexis, Alan Previn wrote:
> On Fri, 2023-10-27 at 10:13 +0300, Jani Nikula wrote:
>> On Thu, 26 Oct 2023, Zhanjun Dong <zhanjun.dong at intel.com> wrote:
>>
> alan:snip
>> I'll note that nobody checks intel_pxp_init() return status, so this
>> silently skips PXP.
>>
>> BR,
>> Jani.
> 
> alan:snip
>>> +	if (intel_gt_is_wedged(gt))
>>> +		return -ENODEV;
>>> +
> 
> alan: wondering if we can add a drm_dbg in the caller of intel_pxp_init and
> use a unique return value for the case of gt_is_wedged (for example: -ENXIO.).
> As we know gt being wedged at startup basically means all gt usage is dead
> and therefore we cant enable PXP (along with everything else that needs submission/
> guc/ etc). With a drm-debug in the caller that prints that return value, it
> helps us to differentiate between gt-is-wedged vs platform config doesnt support
> PXP. However, this would mean new drm-debug 'noise' for platforms that i915 just
> doesn't support PXP on at all which would be okay if dont use drm_warn or drm_err
> and use 'softer' message like "PXP skipped with %d".
> 
> Please treat above comment as a "nit" - i.e. existing patch is good enough for me...
> (after addressing Jani's request for more commit message info). ...alan
> 
> 

Thanks Alan.
I agree, add more drm-debug looks like add noise in case of 
gt_is_wedged, existing code already output useful info.

If logs already let us know gt_wedged happens and we are not expect pxp 
init running on gt wedged condition, then silently skip pxp_init looks 
like match the expectation.

I will re-post with updated commit message later.

Regards,
Zhanjun