[Intel-gfx] [PATCH v3 3/4] drm/i915: Perform TLB invalidation on all GTs during suspend/resume

[John Harrison]

On 10/3/2023 08:59, Andi Shyti wrote:
> Hi Jani,
>
>>> Consider multi-gt support when cancelling all tlb invalidations on
>>> suspend, and when submitting tlb invalidations on resume.
>>>
>>> Suggested-by: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
>>> Signed-off-by: Fei Yang <fei.yang at intel.com>
>>> Signed-off-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
>>> CC: John Harrison <John.C.Harrison at Intel.com>
>> I guess I'm wondering why the top level suspend hook needs to iterate
>> gts instead of some lower level thing. We should aim to reduce
>> gem/gt/display details from the top level.
> I'm not sure I am understanding the question.
>
> The TLB invalidation details are kept under the GT. But when
> suspend is called, then the GT invalidation has to be triggered
> by the top levels for each GT. Right?
I think Jani's point is that the top level should be:
i915_drm_suspend(...) {
    ...
    intel_tlb_suspend(dev_priv);
}

Then the TLB suspend helper function calls into the GT / UC layers as 
appropriate. But none of that internal only detail is exposed at the top 
level.

John.

>
> Thanks,
> Andi