[Mesa-dev] [android-x86-devel] Re: gralloc_drm_pipe

[Chih-Wei Huang]

2016-03-05 3:53 GMT+08:00 Rob Clark <robdclark at gmail.com>:
> On Fri, Mar 4, 2016 at 2:43 PM, Thomas Hellstrom <thellstrom at vmware.com> wrote:
>> On 03/04/2016 07:07 PM, Rob Clark wrote:
>>> On Fri, Mar 4, 2016 at 12:59 PM, Rob Clark <robdclark at gmail.com> wrote:
>>>> So, I've been advocating that for android, gallium drivers use
>>>> gralloc_drm_pipe, since with android it seems like you end up with
>>>> both gralloc and libGL in the same process, and having both share the
>>>> same pipe_screen avoids lots of headaches with multiple gem handles
>>>> pointing to same underlying buffer.
>>>>
>>>> But the awkward thing is that gralloc_drm_pipe is using gallium APIs
>>>> that aren't particularly intended to be used out-of-tree.  Ie. not
>>>> really stable APIs.  At the time, the thing that made sense to me was
>>>> to pull drm_gralloc into mesa.  But at the time, there were no
>>>> non-mesa users of drm_gralloc, which isn't really true anymore.
>>>>
>>>> Maybe what makes more sense now is to implement a gralloc state
>>>> tracker, which exposes a stable API for drm_gralloc?  It would mostly
>>>> be a shim to expose gallium import/export/transfer APIs in a stable
>>>> way, but would also be where the code that figures out which driver to
>>>> use to create/get the pipe_screen.
>>> and actually, we might just be able to use XA state tracker for this..
>>> I think it exposes all the necessary import/export/etc stuff that
>>> gralloc would need..
>>>
>>> BR,
>>> -R
>>>
>> and it was created for a very similar purpose, except that we also
>> needed some
>> render functionality, enough to composite surfaces.
>
> right, and since we have the ability to import/export dmabuf handles,
> I think it is a superset of what is needed.  (gralloc is using blits
> instead of flips for vmwgfx, for reasons I don't fully understand..
> but XA can do these blits and more, so we are still good there)

Hi Rob,
Thank you for raising the problem though
I don't fully understand the technical details.

So you are planning to modify (or re-implement?)
gralloc_drm_pipe to use the APIs of XA state tracker.

Do I understand your words correctly?


-- 
Chih-Wei
Android-x86 project
http://www.android-x86.org