[Letux-kernel] Lay common foundation to make PVR/SGX work without hacks on OMAP34xx, OMAP36xx, AM335x and potentially OMAP4, OMAP5

[H. Nikolaus Schaller]

> Am 12.02.2019 um 21:51 schrieb Tony Lindgren <tony at atomide.com>:
> 
> Hi,
> 
> * H. Nikolaus Schaller <hns at goldelico.com> [190212 20:03]:
>>> Am 11.02.2019 um 07:51 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
>>> What would be the process to get something into staging? Who decides about
>>> staging generally? Should we just forward this discussion to Greg for comment?
>> 
>> One thing already got my attention: we need to prefix all commit messages with e.g.
>> "staging: pvr: " so that they can be distinguished on LKML. I'll prepare that
>> for the next version of our Letux tree.
> 
> After thinking about this a bit, I think a shared out-of-tree
> repo is the best place to start rather than try to stuff a
> pile of sgx and vendor specific hacks into staging.

Well, all drivers are vendor specific... And the driver is already
GPL2 code. And it is not that badly structured as it initially looks.

But It would be ok for me for a shared out-of-tree repo.

> Currently
> we don't even know what all needs to be different for various
> SoCs for example.

Well, the latest IMG DDK already has different wrappers for
several SoC. They are to be found in 

http://git.goldelico.com/?p=letux-kernel.git;a=tree;f=drivers/staging/pvr/1.14.3699939/eurasia_km/services4/system;h=2f4f74da2c86412c6f99dcfb982703c20c96aaed;hb=1d5b6a91eca80168c37ecb66157e675d28666652

This also shows what is needed to change for different SoC.

> 
> And for upstream merging, a minimal generic accelerated 2d
> sgx driver that works across several SoCs is probably the
> best place to start.

Well, I have no need or experience with the 2D drivers at all
so that I can not contribute to that.

> This would make the clock and interrupt
> handling generic with just SoC specific glue layer.

The question is if it is easy or possible to stack the 3d code
on top of that.