[Intel-gfx] [PATCH] drm/i915/mtl: Connect root sysfs entries to GT0

[Belgaumkar, Vinay]

On 1/16/2023 10:58 AM, Andi Shyti wrote:
> Hi,
>
> On Thu, Jan 12, 2023 at 08:48:11PM -0800, Belgaumkar, Vinay wrote:
>> On 1/12/2023 8:37 PM, Dixit, Ashutosh wrote:
>>> On Thu, 12 Jan 2023 20:26:34 -0800, Belgaumkar, Vinay wrote:
>>>> I think the ABI was changed by the patch mentioned in the commit
>>>> (a8a4f0467d70).
>>> The ABI was originally changed in 80cf8af17af04 and 56a709cf77468.
> In theory the ABI has never changed, we just needed to agree once
> and for all what to do when reading the upper level interface.
> There has never been a previous multitile specification before
> this change.
>
> There have been long and exhaustive discussions on what to do and
> the decision is that in some cases we show the average, in others
> the maximum. Never the GT0, though.
>
>> Yes, you are right. @Andi, did we have a plan to update the IGT tests that
>> use these interfaces to properly refer to the per GT entries as well? They
>> now receive average values instead of absolute, hence will fail on a
>> multi-GT device.
> I don't know what's the plan for igt's.
>
> Which tests are failing? I think we shouldn't be using the upper
> level interfaces at all in IGT's. Previously there has been an
> error printed on dmesg when this was happening. The error has
> been removed in order to set the ABI as agreed above.

Tests like perf_mu and gem_ctx_freq will fail as they read upper level 
sysfs entries and expect them to change as per the test. I think this 
includes all of the tests that read RC6 or Trubo related sysfs entries 
for that matter.

Thanks,

Vinay.

>
> Andi