add interface for modifier query

[XinfengZhang]

1. this interface is for modifier query/negotiation. it could query the modifier list for a given format under a config
2. it support different modifier list for different format. for example: ARGB maybe just support linear, RGB maybe support linear only, NV12 support tile4 etc.

[HeJunyan]

Maybe, I think, we just need to extend the "vaQuerySurfaceAttributes" a little.

For example, we define a new type VASurfaceAttribDRMFormatModifiersForFormat after VASurfaceAttribDRMFormatModifiers.

The VASurfaceAttribDRMFormatModifiers return all possible modifiers for a config, while the VASurfaceAttribDRMFormatModifiersForFormat just return the modifiers for some specific format of that config.

And we define a struct, such as:
struct {
uint32_t format;
VADRMFormatModifierList drm_list;
};
as the VAGenericValue.p of that VASurfaceAttrib query. The format is input and drm_list is the output?

Then we can avoid define a new API.

[ceyusa]

Maybe, I think, we just need to extend the "vaQuerySurfaceAttributes" a little.

But that's already in place #505

Sadly, media-driver, neither mesa still no have an implementation for vaQuerySurfaceAttributes. Mesa only implemented the vaCreateSurface part.

[alatteri]

any chance to get this mergered? The capability would help us a lot with color accuracy.

[nowrep]

Sadly, media-driver, neither mesa still no have an implementation for vaQuerySurfaceAttributes. Mesa only implemented the vaCreateSurface part.

That's because it can't be implemented, the modifier query only makes sense when format is specified which is not the case with vaQuerySurfaceAttributes.

So we would need this PR (vaGetSurfaceFormatAttributes) to implement it in Mesa.

[any1]

Does there exist a mesa merge request for this?

[nowrep]

Does there exist a mesa merge request for this?

No, but I can make one if that can help getting this merged.

[any1]

Does there exist a mesa merge request for this?

No, but I can make one if that can help getting this merged.

Well, if you're in the mood for it, I'd say: go for it. ;)

[nowrep]

Mesa impl: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32053

Test app to print all modifiers: https://gist.github.com/nowrep/4c3eab86ad77dcfa605f516b567a66c1