On Wed, Feb 02, 2022 at 01:00:46PM +0200, Ville Syrjälä wrote: > On Wed, Feb 02, 2022 at 12:42:49PM +0200, Imre Deak wrote: > > Make sure all unused power wells left enabled by BIOS get disabled > > during driver loading and system resume. > > > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5028 > > Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/display/intel_display.c | 2 ++ > > .../drm/i915/display/intel_display_power.c | 31 +++++++++++++++++++ > > .../drm/i915/display/intel_display_power.h | 1 + > > 3 files changed, 34 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > > index c431076f98a15..df347329d90e5 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display.c > > +++ b/drivers/gpu/drm/i915/display/intel_display.c > > @@ -10664,6 +10664,8 @@ intel_modeset_setup_hw_state(struct drm_device *dev, > > } > > > > intel_display_power_put(dev_priv, POWER_DOMAIN_INIT, wakeref); > > + > > + intel_power_domains_sanitize_state(dev_priv); > > One slight concern is intel_vga_redisable() which is called after > this during resume. Dunno if there's any way we could end up > disabling the power well that houses the VGA logic before actually > turning off the VGA plane? Yes, it could happen by the time i915_drm_resume()->intel_display_resume() is called. Though, all the power wells backing the VGA functionality are also in the INIT domain, so would have caused a problem already before this patch. i915_restore_display() also calls intel_vga_redisable(), so I think that should handle the above scenario (and the second call can be removed as you suggest below). > Hmm. Maybe we should just reorder the intel_modeset_setup_hw_state() > vs. intel_vga_redisable() anyway. We already do those in the opposite > order during driver probe. No idea why we have a different order for > resume. > > Apart from that this seems sane enough to me. > Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > } > > > > void intel_display_resume(struct drm_device *dev) > > diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c > > index 369317805d245..d2102cc17bb4c 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_power.c > > +++ b/drivers/gpu/drm/i915/display/intel_display_power.c > > @@ -6213,6 +6213,37 @@ void intel_power_domains_driver_remove(struct drm_i915_private *i915) > > intel_runtime_pm_put(&i915->runtime_pm, wakeref); > > } > > > > +/** > > + * intel_power_domains_sanitize_state - sanitize power domains state > > + * @i915: i915 device instance > > + * > > + * Sanitize the power domains state during driver loading and system resume. > > + * The function will disable all display power wells that BIOS has enabled > > + * without a user for it (any user for a power well has taken a reference > > + * on it by the time this function is called, after the state of all the > > + * pipe, encoder, etc. HW resources have been sanitized). > > + */ > > +void intel_power_domains_sanitize_state(struct drm_i915_private *i915) > > +{ > > + struct i915_power_domains *power_domains = &i915->power_domains; > > + struct i915_power_well *power_well; > > + > > + mutex_lock(&power_domains->lock); > > + > > + for_each_power_well_reverse(i915, power_well) { > > + if (power_well->desc->always_on || power_well->count || > > + !power_well->desc->ops->is_enabled(i915, power_well)) > > + continue; > > + > > + drm_dbg_kms(&i915->drm, > > + "BIOS left unused %s power well enabled, disabling it\n", > > + power_well->desc->name); > > + intel_power_well_disable(i915, power_well); > > + } > > + > > + mutex_unlock(&power_domains->lock); > > +} > > + > > /** > > * intel_power_domains_enable - enable toggling of display power wells > > * @i915: i915 device instance > > diff --git a/drivers/gpu/drm/i915/display/intel_display_power.h b/drivers/gpu/drm/i915/display/intel_display_power.h > > index 686d18eaa24c8..a985f0e7ef78b 100644 > > --- a/drivers/gpu/drm/i915/display/intel_display_power.h > > +++ b/drivers/gpu/drm/i915/display/intel_display_power.h > > @@ -219,6 +219,7 @@ void intel_power_domains_disable(struct drm_i915_private *dev_priv); > > void intel_power_domains_suspend(struct drm_i915_private *dev_priv, > > enum i915_drm_suspend_mode); > > void intel_power_domains_resume(struct drm_i915_private *dev_priv); > > +void intel_power_domains_sanitize_state(struct drm_i915_private *dev_priv); > > > > void intel_display_power_suspend_late(struct drm_i915_private *i915); > > void intel_display_power_resume_early(struct drm_i915_private *i915); > > -- > > 2.27.0 > > -- > Ville Syrjälä > Intel
