[Mesa-dev] [PATCH] gbm: add support for loading third-party backend

[Yu, Qiang]

+ David

Hi Emil,

> * With the discussion(s) about liballoc/libgbm2 in motion wouldn't it
> be better to focus/target it ?
[yuq] I think this small improvement won't conflict with libgbm2 work
which is not my current focus. My purpose is getting current mesa co-exist
with amdgpu-pro. BTW. will libgbm2 land soon?

> * As-is most/all of the private GBM API/ABI becomes semi public. As
> such were _really_ want some (ideally all) of the following:
> - clear definition/split which should and shouldn't be part of the
> driver backend API
> - API/ABI tests to catch breakage
> Note: we have broken the ABI a few times already, but since libgbm and
> mesa's libEGL should be (are) from the same tree things haven't
> exploded
[yuq] Seems same requirement and Nicolai's. I can address them next version.

> * The ImgTec guys were able to tweak their binary which combined with
> a bit of mesa glue produces a DRI module.
> This in itself lead of a number of nice improvements and fixes that
> landed in Mesa. Have you/others considered that option ?
[yuq] You mean make amdgpu_dri.so a DRI compatible module which can
be used with the current default GBM DRI backend? But this still need a way
to select which vendor's DRI module because amdgpu_dri.so overlap support
cards with radeonsi_dri.so and the current GBM DRI backend always load
radeonsi_dri.so from a PCIID-DRI table lookup. Also not sure if the ABI is stable 
for different mesa versions? @David what's your opinion?

Regards,
Qiang