From: Wang Yugui <wangyugui@e16-tech.com>
To: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Jocelyn Falempe <jfalempe@redhat.com>,
dri-devel <dri-devel@lists.freedesktop.org>
Subject: Re: mgag200 broken on kernel-6.0-rc3 on DELL/T620
Date: Wed, 14 Sep 2022 22:58:11 +0800 [thread overview]
Message-ID: <20220914225809.763F.409509F4@e16-tech.com> (raw)
In-Reply-To: <03f80477-78c1-2ef3-40bf-58f8c9daa1c8@suse.de>
Hi,
> (cc: Jocelyn)
>
> Hi
>
> Am 14.09.22 um 10:29 schrieb Wang Yugui:
> > Hi,
> >
> >
> >> Hi
> >>
> >> Am 13.09.22 um 17:15 schrieb Wang Yugui:
> >> [...]
> >>>>>
> >>>>> so I tried to revert patch of mgag200 driver in batch of 2 or 3, the I
> >>>>> noticed the patch 'Subject: drm/mgag200: Remove special case for G200SE
> >>>>> with <2 MiB' and then tried this dirty fix.
> >>>>
> >>>> Oh, great work! Thank you. From looking at the screenshot that you provided, it seems as if the 24-bit mode setting is broken. I'm not sure why the G200SE workaround applies to a G200ER, but we'll see.
> >>>
> >>> I tested 'preferred_depth = 32' too. it works on T630 too.
> >>>
> >>> so both 16 and 32 work, but 24 failed on DELL/T630.
> >>
> >> I tried on my test machine with a 5.19 kernel and found that 32-bit and 24-bit pixels work, but 16-bit looks incorrect.
> >>
> >> What are the results if you boot your kernel 5.19.3 with the parameter video=1024x768-24? This should enable 24-bit pixels.
> >>
> >> How does video=1024x768-16 look with the 5.19 kernel?
> >
> > test result here
> > kernel 5.19.3 & video=1024x768-24
> > dell/T620/centos-8.5 broken
> > dell/T630/centos-7.9 broken
>
> I assume that Centos 7 and 8 have fairly old kernels? So it's been a long-standing bug.
We install kernel 5.19.3/5.15.67 into Centos 7 and 8.
default it work well. broken just when 'video=1024x768-24', so it may
not a long-standing bug.
> 24-bit works on my G200HE and G200 test machines. Maybe the G200ER has a bug.
>
> When I try 16-bit depth, the display works, but is way too dark. No fiddling with the LUT tables fixes this. It's 90s hardware, so it should support 16-bit framebuffers well, but there's no obvious bug to be seen.
>
> I guess, we could remove 16 and 24 bit support for now if nothing else helps.
maybe better if we revert 73f54d5d9682 (drm/mgag200: Remove special case
for G200SE with <2 MiB)
because there is no test result on device G200_SE
static unsigned int mgag200_preferred_depth(struct mga_device *mdev)
{
if (IS_G200_SE(mdev) && mdev->vram_fb_available < (2048*1024))
return 16;
else
return 32;
}
Best Regards
Wang Yugui (wangyugui@e16-tech.com)
2022/09/14
next prev parent reply other threads:[~2022-09-14 14:58 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20220902135242.2447.409509F4@e16-tech.com>
2022-09-05 6:57 ` mgag200 broken on kernel-6.0-rc3 on DELL/T620 Thomas Zimmermann
2022-09-07 4:16 ` Wang Yugui
2022-09-07 6:47 ` Thomas Zimmermann
2022-09-07 7:38 ` Wang Yugui
2022-09-07 7:55 ` Thomas Zimmermann
2022-09-07 8:47 ` Wang Yugui
2022-09-07 9:18 ` Thomas Zimmermann
2022-09-13 8:34 ` Thomas Zimmermann
2022-09-13 14:25 ` Wang Yugui
2022-09-13 14:44 ` Thomas Zimmermann
2022-09-13 15:15 ` Wang Yugui
2022-09-14 7:59 ` Thomas Zimmermann
2022-09-14 8:29 ` Wang Yugui
2022-09-14 14:36 ` Thomas Zimmermann
2022-09-14 14:58 ` Wang Yugui [this message]
2022-09-14 15:41 ` Thomas Zimmermann
2022-09-14 16:25 ` Wang Yugui
2022-09-15 12:54 ` Thomas Zimmermann
2022-09-15 14:41 ` Wang Yugui
2022-09-20 7:57 ` Thomas Zimmermann
2022-09-20 9:02 ` Wang Yugui
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220914225809.763F.409509F4@e16-tech.com \
--to=wangyugui@e16-tech.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=jfalempe@redhat.com \
--cc=tzimmermann@suse.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).