[GIT PULL] exynos-drm-next

[Inki Dae]

Hi Daniel,

2015년 10월 28일 19:15에 Daniel Stone 이(가) 쓴 글:
> Hi Inki,
> 
> On 28 October 2015 at 06:55, Inki Dae <inki.dae at samsung.com> wrote:
>>    and revive a Exynos specific interface which was used
>>    to get fake offset, which is required for application using render node
>>    to access a gem memory. For userspace codes for the use of this interface,
>>    you can refer to below link,
>>            https://github.com/dofmind/libdrm/commit/5cc58d765c61b37a26372de9701f3ffe3a1bef70
>>
>>    We will post a patch for libdrm after this patch is merged to mainline.
> 
> Is there any real (non-libdrm) userspace for this? See Daniel Vetter's
> reply to the series here:
> 'In general we wait with merging new userspace ABI until that's really
> ready, since very often there's some corner cases that you just didn't
> think about in your toy demo compared to the real thing. Like how to
> manage buffer caches/reuse for apps that essentially run forever (like X
> server or a compositor).'

Below link is a libdrm codes used by Tizen platform.
https://review.tizen.org/git/?p=platform/upstream/libdrm.git;a=commit;h=6e97f25af63a9511ddd3b195a0b844671b8d1a5d

In Tizen platform, there is a buffer manager called TBM(Tizem Buffer Manager), and
this manager uses this new interface of libdrm.

Tizen platform can use window systems - wayland or X server - according to version.
And the native systems use the TBM interfaces to manage gem buffer.

> 
> Probably my biggest concern is how well this operates with the
> proposed PREP/FINI patches. I would really love to see a real
> userspace which exercises both MAP and PREP/FINI: if that shows

Hmm... Daniel, seems there was your mislead. I will never merge such PREP/FINI interfaces
for cache operation until these will be reviewed enough through real user.
So this pull request doesn't include them. We are just planning to apply these interfaces
to Tizen platform for more test.

Thanks,
Inki Dae

> problems with this interface, then it means we have to carry this
> interface forever, _as well as_ a new cleaned-up one.
> 
> Cheers,
> Daniel
>