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

[Emil Velikov]

Hi Qiang Yu,

On 24 January 2017 at 03:36, Qiang Yu <Qiang.Yu at amd.com> wrote:
> Third-party can put their backend to a directory configured with
> '--with-gbm-backenddir' and create a /etc/gbm.conf.d/*.conf file
> which contains the backend so file name to overwrite the default
> builtin DRI backend.
>
> The /etc/gbm.conf.d/*.conf will be sorted and the backends added
> will be tried one-by-one until one can successfully create a gbm
> device. The default DRI backend is tried at last.
>
> People can still use GBM_BACKEND to overwrite the backend try
> order.
>
Pardon for dropping it late. Here's a few questions that one might
want to consider.

* With the discussion(s) about liballoc/libgbm2 in motion wouldn't it
be better to focus/target it ?

* 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

* 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 ?

Thanks
Emil