[PATCH] drm/mgag200: Increase bandwidth for G200se A rev1

[Jocelyn Falempe]

On 27/07/2023 19:24, Roger Sewell wrote:
> 
> Thomas,
> 
>> Could you provide us with the Xorg logs from /var/log/Xorg.0.log ,
>> please?
>>
>> Specifically, I'd be interested in different logs from combinations of
>> the old and new kernel and the old and new userspace.
> 
> I've managed to do six of the eight possible combinations of kernel,
> mgag200 module, and userspace. The attached archive contains all the
> corresponding Xorg logs as well as a detailed notes file.

Thanks for running all the tests.
> 
> I couldn't do the remaining two combinations because I couldn't get the
> new mgag200 module to compile for the old kernel.
> 
> My previous theory was wrong, but hopefully the attached logs will help
> you work out why the old kernel permitted the high bandwidth mode I
> always use (despite returning MODE_BAD) and the new kernel doesn't.
> 
> (The "old" kernel is 9.1, i.e. 5.14.0-162.6.1.el9_1.0.1, and "new"

For the drm/mgag200 part, it correspond to upstream v5.18 + 3 patches 
(which shouldn't impact the mode check):
c48a36301634 drm/mgag200: Optimize damage clips
3064debaf55e drm/mgag200: Add FB_DAMAGE_CLIPS support
c577b2f43e80 drm/mgag200: Enable atomic gamma lut update

> kernel is 9.2, i.e. 5.14.0-284.18.1.el9_2 .)

And this is equivalent to v6.0


> 
> Best wishes,
> Roger.
>