Nouveau - Nov 2018 - [PATCH] drm/fbdev: Make skip_vt_switch the default

Op 27-11-18 om 18:34 schreef Daniel Vetter:
> KMS drivers really should all be able to restore their display state
> on resume without fbcon helping out. So make this the default.
>
> Since I'm not entirely foolish, make it only a default, which drivers
> can still override. That way when the inevitable regression report
> happens I can fix things up with a one-liner plus FIXME comment that
> someone should fix up the suspend/resume code in that driver.
>
> But at least all new drivers won't be broken by accident as soon as
> you turn off fbcon because "suspend/resume worked when I tested
it".
>
> v2: Keep this for radeon because of
>
> commit 18c437caa5b18a235dd65cec224eab54bebcee65
> Author: Alex Deucher <alexander.deucher at amd.com>
> Date:   Tue Nov 14 17:19:29 2017 -0500
>
>     Revert "drm/radeon: dont switch vt on suspend"
>
> Thanks to Michel Dänzer for pointing this one out.
Maybe just reload the gamma lut on resume for radeon, instead of relying on
fbcon?

Otherwise patch looks sane, would be nice if radeon was fixed instead of worked
around.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

On Wed, Nov 28, 2018 at 08:17:04AM +0100, Maarten Lankhorst
wrote:
> Op 27-11-18 om 18:34 schreef Daniel Vetter:
> > KMS drivers really should all be able to restore their display state
> > on resume without fbcon helping out. So make this the default.
> >
> > Since I'm not entirely foolish, make it only a default, which
drivers
> > can still override. That way when the inevitable regression report
> > happens I can fix things up with a one-liner plus FIXME comment that
> > someone should fix up the suspend/resume code in that driver.
> >
> > But at least all new drivers won't be broken by accident as soon
as
> > you turn off fbcon because "suspend/resume worked when I tested
it".
> >
> > v2: Keep this for radeon because of
> >
> > commit 18c437caa5b18a235dd65cec224eab54bebcee65
> > Author: Alex Deucher <alexander.deucher at amd.com>
> > Date:   Tue Nov 14 17:19:29 2017 -0500
> >
> >     Revert "drm/radeon: dont switch vt on suspend"
> >
> > Thanks to Michel Dänzer for pointing this one out.
> 
> Maybe just reload the gamma lut on resume for radeon, instead of relying on
fbcon?
It also caused random sound issues and other fun. Also, afaiui radeon does
load the lut. Except because of timing or bad luck, it doesn't work
reliably, and the vt switch doing it a 2nd time helps out.
-Daniel
> Otherwise patch looks sane, would be nice if radeon was fixed instead of
worked around.
> 
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Reviewed-by: Samuel Li <samuel.li at amd.com>



On 2018-11-28 3:20 a.m., Daniel Vetter wrote:
> On Wed, Nov 28, 2018 at 08:17:04AM +0100, Maarten Lankhorst wrote:
>> Op 27-11-18 om 18:34 schreef Daniel Vetter:
>>> KMS drivers really should all be able to restore their display
state
>>> on resume without fbcon helping out. So make this the default.
>>>
>>> Since I'm not entirely foolish, make it only a default, which
drivers
>>> can still override. That way when the inevitable regression report
>>> happens I can fix things up with a one-liner plus FIXME comment
that
>>> someone should fix up the suspend/resume code in that driver.
>>>
>>> But at least all new drivers won't be broken by accident as
soon as
>>> you turn off fbcon because "suspend/resume worked when I
tested it".
>>>
>>> v2: Keep this for radeon because of
>>>
>>> commit 18c437caa5b18a235dd65cec224eab54bebcee65
>>> Author: Alex Deucher <alexander.deucher at amd.com>
>>> Date:   Tue Nov 14 17:19:29 2017 -0500
>>>
>>>     Revert "drm/radeon: dont switch vt on suspend"
>>>
>>> Thanks to Michel Dänzer for pointing this one out.
>>
>> Maybe just reload the gamma lut on resume for radeon, instead of
relying on fbcon?
> 
> It also caused random sound issues and other fun. Also, afaiui radeon does
> load the lut. Except because of timing or bad luck, it doesn't work
> reliably, and the vt switch doing it a 2nd time helps out.
> -Daniel
> 
>> Otherwise patch looks sane, would be nice if radeon was fixed instead
of worked around.
>>
>> Reviewed-by: Maarten Lankhorst <maarten.lankhorst at
linux.intel.com>

On Wed, Nov 28, 2018 at 8:17 AM Maarten Lankhorst
<maarten.lankhorst at linux.intel.com> wrote:
>
> Op 27-11-18 om 18:34 schreef Daniel Vetter:
> > KMS drivers really should all be able to restore their display state
> > on resume without fbcon helping out. So make this the default.
> >
> > Since I'm not entirely foolish, make it only a default, which
drivers
> > can still override. That way when the inevitable regression report
> > happens I can fix things up with a one-liner plus FIXME comment that
> > someone should fix up the suspend/resume code in that driver.
> >
> > But at least all new drivers won't be broken by accident as soon
as
> > you turn off fbcon because "suspend/resume worked when I tested
it".
> >
> > v2: Keep this for radeon because of
> >
> > commit 18c437caa5b18a235dd65cec224eab54bebcee65
> > Author: Alex Deucher <alexander.deucher at amd.com>
> > Date:   Tue Nov 14 17:19:29 2017 -0500
> >
> >     Revert "drm/radeon: dont switch vt on suspend"
> >
> > Thanks to Michel Dänzer for pointing this one out.
>
> Maybe just reload the gamma lut on resume for radeon, instead of relying on
fbcon?
>
> Otherwise patch looks sane, would be nice if radeon was fixed instead of
worked around.
>
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Noticed this old patch, finally gotten around to merging it. Thanks
everyone for reviewing.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch