[Mesa-dev] [PATCH 3/7] mesa/st: support lowering multi-planar YUV
Roland Scheidegger
sroland at vmware.com
Sat Sep 10 14:04:03 UTC 2016
Am 09.09.2016 um 02:58 schrieb Rob Clark:
> On Thu, Sep 8, 2016 at 8:28 PM, Roland Scheidegger <sroland at vmware.com> wrote:
>> Am 09.09.2016 um 02:19 schrieb Rob Clark:
>>> On Thu, Sep 8, 2016 at 7:54 PM, Rob Clark <robdclark at gmail.com> wrote:
>>>> On Thu, Sep 8, 2016 at 6:41 PM, Roland Scheidegger <sroland at vmware.com> wrote:
>>>>> Am 08.09.2016 um 23:43 schrieb Rob Clark:
>>>>>> On Thu, Sep 8, 2016 at 5:11 PM, Roland Scheidegger <sroland at vmware.com> wrote:
>>>>>>> Am 08.09.2016 um 22:30 schrieb Rob Clark:
>>>>>>>> Support multi-planar YUV for external EGLImage's (currently just in the
>>>>>>>> dma-buf import path) by lowering to multiple texture fetch's for each
>>>>>>>> plane and CSC in shader.
>>>>>>>>
>>>>>>>> Signed-off-by: Rob Clark <robdclark at gmail.com>
>>>>>>>> ---
>>>>>>>> src/gallium/auxiliary/util/u_inlines.h | 4 +-
>>>>>>>> src/gallium/include/pipe/p_state.h | 9 +++
>>>>>>>> src/gallium/include/state_tracker/st_api.h | 3 +
>>>>>>>> src/gallium/state_trackers/dri/dri2.c | 119 +++++++++++++++++++++++-----
>>>>>>>> src/gallium/state_trackers/dri/dri_screen.c | 11 +++
>>>>>>>> src/mesa/main/mtypes.h | 16 ++++
>>>>>>>> src/mesa/program/ir_to_mesa.cpp | 1 +
>>>>>>>> src/mesa/state_tracker/st_atom_sampler.c | 41 +++++++++-
>>>>>>>> src/mesa/state_tracker/st_atom_shader.c | 3 +
>>>>>>>> src/mesa/state_tracker/st_atom_texture.c | 58 ++++++++++++++
>>>>>>>> src/mesa/state_tracker/st_cb_eglimage.c | 18 +++++
>>>>>>>> src/mesa/state_tracker/st_context.c | 7 +-
>>>>>>>> src/mesa/state_tracker/st_glsl_to_nir.cpp | 1 +
>>>>>>>> src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 4 +
>>>>>>>> src/mesa/state_tracker/st_manager.c | 1 +
>>>>>>>> src/mesa/state_tracker/st_program.c | 35 ++++++++
>>>>>>>> src/mesa/state_tracker/st_program.h | 37 +++++++++
>>>>>>>> src/mesa/state_tracker/st_texture.h | 21 +++++
>>>>>>>> 18 files changed, 362 insertions(+), 27 deletions(-)
>>>>>>>>
>>>>>>>> diff --git a/src/gallium/auxiliary/util/u_inlines.h b/src/gallium/auxiliary/util/u_inlines.h
>>>>>>>> index c2a0b08..b7b8313 100644
>>>>>>>> --- a/src/gallium/auxiliary/util/u_inlines.h
>>>>>>>> +++ b/src/gallium/auxiliary/util/u_inlines.h
>>>>>>>> @@ -136,8 +136,10 @@ pipe_resource_reference(struct pipe_resource **ptr, struct pipe_resource *tex)
>>>>>>>> struct pipe_resource *old_tex = *ptr;
>>>>>>>>
>>>>>>>> if (pipe_reference_described(&(*ptr)->reference, &tex->reference,
>>>>>>>> - (debug_reference_descriptor)debug_describe_resource))
>>>>>>>> + (debug_reference_descriptor)debug_describe_resource)) {
>>>>>>>> + pipe_resource_reference(&old_tex->next, NULL);
>>>>>>>> old_tex->screen->resource_destroy(old_tex->screen, old_tex);
>>>>>>>> + }
>>>>>>>> *ptr = tex;
>>>>>>>> }
>>>>>>>>
>>>>>>>> diff --git a/src/gallium/include/pipe/p_state.h b/src/gallium/include/pipe/p_state.h
>>>>>>>> index ebd0337..4a88da6 100644
>>>>>>>> --- a/src/gallium/include/pipe/p_state.h
>>>>>>>> +++ b/src/gallium/include/pipe/p_state.h
>>>>>>>> @@ -498,6 +498,15 @@ struct pipe_resource
>>>>>>>>
>>>>>>>> unsigned bind; /**< bitmask of PIPE_BIND_x */
>>>>>>>> unsigned flags; /**< bitmask of PIPE_RESOURCE_FLAG_x */
>>>>>>>> +
>>>>>>>> + /**
>>>>>>>> + * For planar images, ie. YUV EGLImage external, etc, pointer to the
>>>>>>>> + * next plane.
>>>>>>>> + *
>>>>>>>> + * TODO might be useful for dealing w/ z32s8 too, since at least a
>>>>>>>> + * couple drivers split these out into separate buffers internally.
>>>>>>>> + */
>>>>>>>> + struct pipe_resource *next;
>>>>>>> Would it be possible to stuff the multiple resources somewhere else
>>>>>>> (__DRIImage ?)? Seems a bit of a hack to have resources referencing
>>>>>>> other resources that way.
>>>>>>> (Also, it's odd since things are mostly lowered really outside of
>>>>>>> gallium so it's odd that some of the yuv state still sneaks in there.)
>>>>>>
>>>>>> I did originally start down the path of making __DRIImage have
>>>>>> multiple pipe_resource's.. I'm not really sure that would end up
>>>>>> better, and it certainly would be more invasive.
>>>>>>
>>>>>> Maybe we should just make that something like 'void *stpriv' to let st
>>>>>> stick whatever it wants in there. That seems more sane than making
>>>>>> the st use a hashtable to map the rsc back to something else.
>>>>>
>>>>> Can't you just put 3 resources in somewhere without pointers?
>>>>> I just think it really should be outside gallium interfaces. The
>>>>> lowering is all done by the state tracker, hence having those bits there
>>>>> referencing other resources in gallium looks wrong to me.
>>>>>
>>>>
>>>> It would require a *lot* of changes to change st_texture_object::pt
>>>> into an array in mesa/st, I think.. plus a bunch of re-working the
>>>> egl-img code in mesa/st.. that sounds like a much worse option to me.
>>>>
>>>> Having a 'void *' opaque pointer in the resource (rather than a
>>>> 'struct pipe_resource *next') for the st to do whatever it wants with
>>>> seems semi-sane to me. And plausibly useful to other st's as well.
>>>>
>>>> *however* making it an opaque ptr (or even handling it purely in
>>>> mesa/st) seems like a slight disadvantage compared to current patch..
>>>> unref'ing rsc->next in pipe_resource_reference() is a nice benefit of
>>>> the current approach..
>>>>
>>>> At the end of the day, I'm less a fan of making this all much harder
>>>> for the st only for the benefit of some hypothetical API "purity" ;-)
>>>
>>> (or perhaps a better way to word that is "I'm a fan of pragmatism" ;-))
>>>
>>
>> Oh I'm all for pragmatism.
>> Yet I still care about api purity somewhat. But gallium is an interface
>> for hw drivers. Yet there's now this new field in pipe_resource which
>> the drivers should ignore - i.e. it's only really there for the state
>> tracker, it serves no purpose for the driver seemingly. Therefore it
>> shouldn't be there. Essentially you've hidden all the nasty
>> multi-sampler and color conversion stuff from the drivers, yet somehow
>> the resources themselves are still different.
>> Maybe I'm naive but why would it be more work to put that into the
>> appropriate state tracker structure instead?
>
> I guess I would say that if we were starting from scratch, and that
> mesa/st (and various interfaces between it and egl/dri2 bits) didn't
> already exist, then I would agree with you.. probably.. although I
> think the case could still be made that there is some convenience in
> being able to treat multi-planar resources as a single thing (whether
> it be yuv or weird z/s formats)
Even if there were (and I don't really agree there) that's not _quite_
what this does. Multiple linked resources aren't exactly the same thing
as a single resource with multiple planes (obviously some parameters
have to match).
>
> But mesa/st is already rather big, and the change isn't completely
> contained in mesa/st. So changing st_texture_object to encapsulate
> multiple resources would be much more invasive and significantly
> larger patchset.
I suppose it would need some changes so you actually get the multiple
resources into st_texture_object, but from an interface perspective that
would imho be better. You've decided the state tracker does the lowering
of the multi-planar yuv stuff, so it should do all of it and not do most
of it and leave the weirdo resources intact - I consider that a gross
hack and abuse of the gallium interface. But I'm not going to stop you,
whatever works...
Roland
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