[Intel-gfx] [PATCH 3/3] drm/i915: Fix plane watermark mismatches

[Souza, Jose]

On Fri, 2021-02-12 at 23:13 +0200, Ville Syrjälä wrote:
> On Fri, Feb 12, 2021 at 07:44:22PM +0000, Souza, Jose wrote:
> > On Fri, 2021-02-12 at 20:35 +0200, Ville Syrjälä wrote:
> > > On Fri, Feb 12, 2021 at 10:22:01AM -0800, José Roberto de Souza wrote:
> > > > Found a system were firmware/BIOS left the plane_res_b and plane_res_l
> > > > set with non-zero values for disable planes.
> > > 
> > > It pretty much happens always since the reset value is not zero.
> > > IIRC we made the state chcker pedantic enough to complain about
> > > that, so we need to clean it up.
> > 
> > Are you planning to fix it soon?
> 
> Fix what exactly? I guess you're seeing an actual problem of some sort?

Your comment above made me understand that you were planning to fix this plane watermark mismatches for disabled planes in other way other than what
this patch does.
Or should we proceed with this solution? 

> 
> > If not I can do it but will need a couple more of hints of what you
> > thinking to do.
> > 
> > We will need this fixed soon otherwise this system will block CI
> > testing in this platform.
> > 
> > > 
> > > > As the planes are disabled i915 will not even try to sanitize it so
> > > > here returning earlier if both skl_wm_levels being compared are
> > > > disabled, if that is true no need to check the other fields as HW
> > > > will ignore it.
> > > > 
> > > > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > > > ---
> > > >  drivers/gpu/drm/i915/intel_pm.c | 2 ++
> > > >  1 file changed, 2 insertions(+)
> > > > 
> > > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > > > index 8cc67f9c4e58..c630dc10c34b 100644
> > > > --- a/drivers/gpu/drm/i915/intel_pm.c
> > > > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > > > @@ -5633,6 +5633,8 @@ void skl_write_cursor_wm(struct intel_plane *plane,
> > > >  bool skl_wm_level_equals(const struct skl_wm_level *l1,
> > > >  			 const struct skl_wm_level *l2)
> > > >  {
> > > > +	if (l1->plane_en == false && l2->plane_en == false)
> > > > +		return true;
> > > >  	return l1->plane_en == l2->plane_en &&
> > > >  		l1->ignore_lines == l2->ignore_lines &&
> > > >  		l1->plane_res_l == l2->plane_res_l &&
> > > > -- 
> > > > 2.30.1
> > > > 
> > > > _______________________________________________
> > > > Intel-gfx mailing list
> > > > Intel-gfx at lists.freedesktop.org
> > > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> > > 
> > 
>