Enable AMDGPU for CIK by default

[Michel Dänzer]

On 07/11/16 11:25 PM, Bridgman, John wrote:
>> From: dri-devel [mailto:dri-devel-bounces at lists.freedesktop.org] On Behalf
>> Of Michel Dänzer
>> Sent: Monday, November 07, 2016 2:24 AM
>> On 07/11/16 03:56 AM, Sandeep wrote:
>>>
>>> I was wondering when DRM_AMDGPU_CIK would be turned on by default
>> in
>>> the upstream kernel (or is this upto individual distros?)
>>>
>>> Is there any work left to be done/bugs to be fixed before it can be
>>> enabled by default?
>>
>> There are still some functional regressions, notably amdgpu doesn't support
>> HDMI/DP audio yet.
>>
>> Also, simply enabling DRM_AMDGPU_CIK by default isn't a good solution,
>> since the radeon driver also still supports the CIK devices, and there's no
>> good mechanism to choose which driver gets to drive a particular GPU at
>> runtime.
> 
> Right... we would need corresponding logic to disable CIK support in radeon. 
> 
> Would we need two flags, one for each driver, or could we define a flag at
> drivers/gpu/drm level which would choose between radeon and amdgpu for
> CIK hardware ?

Technically, there's probably nothing preventing the radeon code from
using CONFIG_DRM_AMDGPU_CIK/SI as well.


> Even as I type that I don't like it... so two flags I guess.

It might actually be useful to have support in drivers and be able to
choose one or the other at runtime. Somebody "just" needs to come up
with a suitable mechanism for that choice.


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