Hi,
> Hi
>
> Am 13.09.22 um 16:25 schrieb Wang Yugui:
> > Hi,
> >
> >> Hi
> >>
> >> Am 07.09.22 um 06:16 schrieb Wang Yugui:
> >>> Hi,
> >>>
> >>>> Am 02.09.22 um 07:52 schrieb Wang Yugui:
> >>>>> Hi,
> >>>>>
> >>>>> mgag200 broken on kernel-6.0-rc3 on DELL/T620.
> >>>>>
> >>>>> See the attachementment file for the graph output.
> >>>>
> >>>> Thanks for reporting the bug. We recently refactored some code of the
> >>>> driver. Can you bisect to the change that introduced the problem?
> >>>
> >>> 5.19.3 works well on this DELL/T620.
> >>>
> >>> so this problem should be a regression of 6.0.
> >>>
> >>> other bisect seem difficult for me.
> >>
> >> I looked for changes between 5.19 and 6.0-rc3 that could affect G200ER
> >> specifically, but could not find anything. It would help if I'd know the
> >> first broken commit. Is there any chance that you get the git bisecting to
> >> work?
> >>
> >> The commands should be
> >>
> >> git bisect reset
> >> git bisect start v6.0-rc3 v5.19
> >
> > A dirty patch(below) works well. but we need a final fix.
> >
> > # git diff
> > diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c
> > b/drivers/gpu/drm/mgag200/mgag200_mode.c
> > index 225cca2ed60e..cd976baa2f44 100644
> > --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> > +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> > @@ -1070,7 +1070,7 @@ int mgag200_modeset_init(struct mga_device *mdev,
> > resource_size_t vram_available
> >
> > dev->mode_config.max_width = MGAG200_MAX_FB_WIDTH;
> > dev->mode_config.max_height = MGAG200_MAX_FB_HEIGHT;
> > - dev->mode_config.preferred_depth = 24;
> > + dev->mode_config.preferred_depth = 16;
> > dev->mode_config.fb_base = mdev->vram_res->start;
> > dev->mode_config.funcs = &mgag200_mode_config_funcs;
> >
> > I firstly tried to build whole kernel base on
> > c577b2f43e80 drm/mgag200: Enable atomic gamma lut update
> > d45e32c9d98c drm/mgag200: Call mgag200_device_probe_vram() from
> > per-model init
> >
> > both failed to boot, so failed to test mgag200 driver.
> >
> > 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.
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c
b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 225cca2ed60e..563e3ab05fbc 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -1070,7 +1070,7 @@ int mgag200_modeset_init(struct mga_device *mdev,
resource_size_t vram_available
dev->mode_config.max_width = MGAG200_MAX_FB_WIDTH;
dev->mode_config.max_height = MGAG200_MAX_FB_HEIGHT;
- dev->mode_config.preferred_depth = 24;
+ dev->mode_config.preferred_depth = 32;
dev->mode_config.fb_base = mdev->vram_res->start;
dev->mode_config.funcs = &mgag200_mode_config_funcs;
Best Regards
Wang Yugui (wangyu...@e16-tech.com)
2022/09/13
