[PATCH 1/2] drm/amdgpu: access stolen VRAM directly on KV/KB

[Michel Dänzer]

On 07/11/16 06:33 PM, Christian König wrote:
> Am 07.11.2016 um 10:29 schrieb Michel Dänzer:
>> On 07/11/16 06:21 PM, Christian König wrote:
>>> From: Christian König <christian.koenig at amd.com>
>>>
>>> We don't need to use the PCI BAR on APUs. This allows us to access
>>> the full VRAM directly without being limited by the BAR size.
>>>
>>> Signed-off-by: Christian König <christian.koenig at amd.com>
>> The series is
>>
>> Reviewed-by: Michel Dänzer <michel.daenzer at amd.com>
>>
>>
>> We could also drop the HDP flushes / invalidates in this case, right?
> Could be, but I'm not 100% sure how those are actually wired up on APUs.
> 
> Might be that they are NOPs anyway, but could be that at least the
> flushes are still vital.

My assumption is that since CPU access to VRAM doesn't go through the
HDP at all with this change, HDP flushes / invalidates can't have any
useful effect.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer