[PATCH] drm/mgag200: Force 32 bpp on the console

[Thomas Zimmermann]

Hi

Am 19.09.22 um 17:25 schrieb Jocelyn Falempe:
> On 15/09/2022 17:03, Thomas Zimmermann wrote:
>> G200ER does not seem to support 24 bpp, so force the console to
>> use 32 bpp. The problem was introduced, when commit 73f54d5d9682
>> ("drm/mgag200: Remove special case for G200SE with <2 MiB") changed
>> the preferred color depth from 32 bit to 24 bit.
>>
>> A setting of 24 is the correct color depth, but G200ER doesn't seem
>> to be able to use the respective RGB888 color format. Using 24-bit
>> color with forced 32 bpp works around the problem.
> 
> Thanks for the patch.
> At least on my G200EW, 24 bpp is working well. So maybe only the G200ER 
> is affected.

I could not reproduce the problem either. Probably only G200ER is 
affected. Javier suggested to make add a quirk specifically for the 
particular DELL machine.

In the drm-tip, the code has meanwhile been split up by hardware 
revisions. So we can fix the problem by not exporting RGB888 at all on 
G200ER.

Best regards
Thomas

> I think it may have a performance penalty, I will try to measure it. >
> Reviewed-by: Jocelyn Falempe <jfalempe at redhat.com>
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature
Type: application/pgp-signature
Size: 840 bytes
Desc: OpenPGP digital signature
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20220920/9446ea43/attachment.sig>