Re: [QEMU PATCH v4 12/13] virtio-gpu: Initialize Venus

[Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>]

On 9/9/23 13:53, Huang Rui wrote:
> On Thu, Aug 31, 2023 at 11:51:50PM +0800, Dmitry Osipenko wrote:
>> On 8/31/23 13:40, Antonio Caggiano wrote:
>>> Hi Huang,
>>>
>>> Thank you for pushing this forward!
>>>
>>> On 31/08/2023 11:32, Huang Rui wrote:
>>>> From: Antonio Caggiano <antonio.caggiano@xxxxxxxxxxxxx>
>>>>
>>>> Request Venus when initializing VirGL.
>>>>
>>>> Signed-off-by: Antonio Caggiano <antonio.caggiano@xxxxxxxxxxxxx>
>>>> Signed-off-by: Huang Rui <ray.huang@xxxxxxx>
>>>> ---
>>>>
>>>> v1->v2:
>>>>      - Rebase to latest version
>>>>
>>>>   hw/display/virtio-gpu-virgl.c | 2 ++
>>>>   1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/hw/display/virtio-gpu-virgl.c
>>>> b/hw/display/virtio-gpu-virgl.c
>>>> index 83cd8c8fd0..c5a62665bd 100644
>>>> --- a/hw/display/virtio-gpu-virgl.c
>>>> +++ b/hw/display/virtio-gpu-virgl.c
>>>> @@ -887,6 +887,8 @@ int virtio_gpu_virgl_init(VirtIOGPU *g)
>>>>       }
>>>>   #endif
>>>>   +    flags |= VIRGL_RENDERER_VENUS;
>>>> +
>>>
>>> VIRGL_RENDERER_VENUS is a symbol only available from virglrenderer 0.9.1
>>> [0] and only if VIRGL_RENDERER_UNSTABLE_APIS is defined.
>>>
>>> Luckily for us, VIRGL_RENDERER_UNSTABLE_APIS is defined unconditionally
>>> from virglrenderer 0.9.0 [1], so we could check for that in
>>> qemu/meson.build
>>>
>>> e.g.
>>>
>>>
>>>   if virgl.version().version_compare('>= 0.9.0')
>>>     message('Enabling virglrenderer unstable APIs')
>>>     virgl = declare_dependency(compile_args:
>>> '-DVIRGL_RENDERER_UNSTABLE_APIS',
>>>                                dependencies: virgl)
>>>   endif
>>>
>>>
>>> Also, while testing this with various versions of virglrenderer, I
>>> realized there are no guarantees for Venus backend to be available in
>>> the linked library. Virglrenderer should be built with
>>> -Dvenus_experimental=true, and if that is not the case, the following
>>> virgl_renderer_init would fail for previous versions of virglrenderer or
>>> in case it has not been built with venus support.
>>>
>>> I would suggest another approach for that which tries initializing Venus
>>> only if VIRGL_RENDERER_VENUS is actually defined. Then, if it fails
>>> cause virglrenderer has not been built with venus support, try again
>>> falling back to virgl only.
>>
>> All the APIs will be stabilized with the upcoming virglrender 1.0
>> release that will happen soon. There is also a venus protocol bump, qemu
>> will have to bump virglrenderer's version dependency to 1.0 for venus
>> and other new features.
>>
> 
> Dmitry, do you know the timeline of virglrender 1.0?

Should be end of this week or next week

-- 
Best regards,
Dmitry