[PATCH] drm/amdgpu/gmc: use PCI BARs for APUs in passthrough

[Michel Dänzer]

On 2022-03-16 16:55, Alex Deucher wrote:
> On Wed, Mar 16, 2022 at 11:52 AM Michel Dänzer
> <michel.daenzer at mailbox.org> wrote:
>>
>> On 2022-03-11 18:43, Michel Dänzer wrote:
>>> On 2022-03-11 11:32, Christian König wrote:
>>>> Am 11.03.22 um 11:24 schrieb Michel Dänzer:
>>>>> On 2022-03-10 19:06, Alex Deucher wrote:
>>>>>> If the GPU is passed through to a guest VM, use the PCI
>>>>>> BAR for CPU FB access rather than the physical address of
>>>>>> carve out.  The physical address is not valid in a guest.
>>>>> I think amdgpu_device_flush_hdp & amdgpu_device_invalidate_hdp need to be modified accordingly.
>>>
>>> I'm surprised you gave your R-b despite this. Surely the HDP cache needs to be handled when going through the BAR?
>>
>> I'm a bit confused why there's still been no response on this point from either of you. Are you guys checking internally whether or not this is needed?
> 
> Yes, it is needed.  I added it in v2 of the patch.

Ah, great, hadn't seen the v2 patch yet. :)


-- 
Earthling Michel Dänzer            |                  https://redhat.com
Libre software enthusiast          |         Mesa and Xwayland developer