| Message ID | 20200228203552.30273-1-ville.syrjala@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/4] drm/i915: Don't check uv_wm in skl_plane_wm_equals() | expand |
On Fri, 2020-02-28 at 22:35 +0200, Ville Syrjala wrote: > From: Ville Syrjälä <ville.syrjala@linux.intel.com> > > The hardware never sees the uv_wm values (apart from > uv_wm.min_ddb_alloc affecting the ddb allocation). Thus there > is no point in comparing uv_wm to determine if we need to > reprogram the watermark registers. So let's check only the > rgb/y watermark in skl_plane_wm_equals(). But let's leave > a comment behind so that the next person reading this doesn't > get as confused as I did when I added this check. > > If the ddb allocation ends up changing due to uv_wm > skl_ddb_add_affected_planes() takes care of adding the plane > to the state. > > TODO: we should perhaps just eliminate uv_wm from the state > and simply track the min_ddb_alloc for uv instead. > Reviewed-by: José Roberto de Souza <jose.souza@intel.com> > Cc: Matt Roper <matthew.d.roper@intel.com> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> > --- > drivers/gpu/drm/i915/intel_pm.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_pm.c > b/drivers/gpu/drm/i915/intel_pm.c > index 345429e5ad45..39299811b650 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -5400,8 +5400,12 @@ static bool skl_plane_wm_equals(struct > drm_i915_private *dev_priv, > int level, max_level = ilk_wm_max_level(dev_priv); > > for (level = 0; level <= max_level; level++) { > - if (!skl_wm_level_equals(&wm1->wm[level], &wm2- > >wm[level]) || > - !skl_wm_level_equals(&wm1->uv_wm[level], &wm2- > >uv_wm[level])) > + /* > + * We don't check uv_wm as the hardware doesn't > actually > + * use it. It only gets used for calculating the > required > + * ddb allocation. > + */ > + if (!skl_wm_level_equals(&wm1->wm[level], &wm2- > >wm[level])) > return false; > } >
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 345429e5ad45..39299811b650 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5400,8 +5400,12 @@ static bool skl_plane_wm_equals(struct drm_i915_private *dev_priv, int level, max_level = ilk_wm_max_level(dev_priv); for (level = 0; level <= max_level; level++) { - if (!skl_wm_level_equals(&wm1->wm[level], &wm2->wm[level]) || - !skl_wm_level_equals(&wm1->uv_wm[level], &wm2->uv_wm[level])) + /* + * We don't check uv_wm as the hardware doesn't actually + * use it. It only gets used for calculating the required + * ddb allocation. + */ + if (!skl_wm_level_equals(&wm1->wm[level], &wm2->wm[level])) return false; }