[PATCH v2] drm/amd/display: Look at firmware version to determine using dmub on dcn21

[Limonciello, Mario]

[Public]

> -----Original Message-----
> From: Li, Roman <Roman.Li at amd.com>
> Sent: Friday, October 29, 2021 18:12
> To: Alex Deucher <alexdeucher at gmail.com>; Limonciello, Mario
> <Mario.Limonciello at amd.com>
> Cc: amd-gfx list <amd-gfx at lists.freedesktop.org>
> Subject: RE: [PATCH v2] drm/amd/display: Look at firmware version to
> determine using dmub on dcn21
> 
> [Public]
> 
> > -----Original Message-----
> > From: Alex Deucher <alexdeucher at gmail.com>
> > Sent: Friday, October 29, 2021 4:34 PM
> > To: Limonciello, Mario <Mario.Limonciello at amd.com>
> > Cc: amd-gfx list <amd-gfx at lists.freedesktop.org>; Li, Roman
> > <Roman.Li at amd.com>
> > Subject: Re: [PATCH v2] drm/amd/display: Look at firmware version to
> > determine using dmub on dcn21
> >
> > On Fri, Oct 29, 2021 at 4:33 PM Mario Limonciello
> > <mario.limonciello at amd.com> wrote:
> > >
> > > commit b1c61212d8dc ("drm/amd/display: Fully switch to dmub for all
> > > dcn21
> > > asics") switched over to using dmub on Renoir to fix Gitlab 1735, but
> > > this implied a new dependency on newer firmware which might not be met
> > > on older kernel versions.
> > >
> > > Since sw_init runs before hw_init, there is an opportunity to
> > > determine whether or not the firmware version is new to adjust the
> behavior.
> > >
> > > Cc: Roman.Li at amd.com
> > > BugLink:
> > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitl
> > > ab.freedesktop.org%2Fdrm%2Famd%2F-
> > %2Fissues%2F1772&data=04%7C01%7C
> > >
> >
> Roman.Li%40amd.com%7C4e27c983112e4ffdd36008d99b1b860a%7C3dd8961f
> > e4884e
> > >
> >
> 608e11a82d994e183d%7C0%7C0%7C637711364793611804%7CUnknown%7CT
> > WFpbGZsb3
> > >
> >
> d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3
> > D%7
> > >
> >
> C1000&sdata=cFwunb4aAJbFkCe6lIFMY4oWfbkCVWAGshe8lB0rg0U%3D&
> > amp;res
> > > erved=0
> > > BugLink:
> > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitl
> > > ab.freedesktop.org%2Fdrm%2Famd%2F-
> > %2Fissues%2F1735&data=04%7C01%7C
> > >
> >
> Roman.Li%40amd.com%7C4e27c983112e4ffdd36008d99b1b860a%7C3dd8961f
> > e4884e
> > >
> >
> 608e11a82d994e183d%7C0%7C0%7C637711364793611804%7CUnknown%7CT
> > WFpbGZsb3
> > >
> >
> d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3
> > D%7
> > >
> >
> C1000&sdata=%2F9sfVD5PN2tsl0bXkctPzkrHpJKQoZDex8xCDt1bVPg%3D&
> > amp;r
> > > eserved=0
> > > Fixes: b1c61212d8dc ("drm/amd/display: Fully switch to dmub for all
> > > dcn21 asics")
> > > Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
> >
> > Acked-by: Alex Deucher <alexander.deucher at amd.com>
> >
> > > ---
> > >  drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 +++
> > >  1 file changed, 3 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > index 6dd6262f2769..e7ff8ad4c5a7 100644
> > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> > > @@ -1410,7 +1410,10 @@ static int amdgpu_dm_init(struct amdgpu_device
> > *adev)
> > >                 switch (adev->ip_versions[DCE_HWIP][0]) {
> > >                 case IP_VERSION(2, 1, 0):
> > >                         init_data.flags.gpu_vm_support = true;
> > > +                       if
> > > + (ASICREV_IS_GREEN_SARDINE(adev->external_rev_id))
> > >                                 init_data.flags.disable_dmcu = true;
> > > +                       else
> > > +                               init_data.flags.disable_dmcu =
> > > + adev->dm.dmcub_fw_version > 0x01000000;
> 
> Since this is the only fw version that needs dmcu, it's safer to use equal condition
> here.

Are you sure nothing older needs it?  Or are you just thinking because this is the
"first firmware" that is released?

I seem to recall seeing this in a log that worked with it set to "false":

[drm] Loading DMUB firmware via PSP: version=0x00000001

> 
> > >                         break;
> > >                 case IP_VERSION(1, 0, 0):
> > >                 case IP_VERSION(1, 0, 1):
> > > --
> > > 2.25.1
> > >