[Intel-gfx] [PATCH v2 3/4] drm/i915/display/adlp: Fix programing of PIPE_MBUS_DBOX_CTL

Souza, Jose jose.souza at intel.com
Thu Mar 24 12:58:32 UTC 2022


On Thu, 2022-03-24 at 13:30 +0200, Ville Syrjälä wrote:
> On Tue, Mar 22, 2022 at 02:46:15PM -0700, José Roberto de Souza wrote:
> > PIPE_MBUS_DBOX_CTL was only being programmed when a pipe is being
> > enabled but that could potentially cause issues as it could have
> > mismatching values while pipes are being enabled.
> > 
> > So here moving the PIPE_MBUS_DBOX_CTL programming of all pipes to be
> > executed before the function that enables all pipes, leaving all pipes
> > with a matching A_CREDIT value.
> > 
> > While at it, also moving it to intel_pm.c as we are trying to reduce
> > the gigantic size of it and intel_pm.c have other MBUS programing
> > sequences.
> > 
> > v2:
> > - do not program PIPE_MBUS_DBOX_CTL if pipe will not be active or
> > when it do not needs modeset
> > - remove the checks to wait a vblank
> > 
> > BSpec: 49213
> > BSpec: 50343
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c | 37 +--------------
> >  drivers/gpu/drm/i915/intel_pm.c              | 47 ++++++++++++++++++++
> >  drivers/gpu/drm/i915/intel_pm.h              |  1 +
> >  3 files changed, 49 insertions(+), 36 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index 424cd7e9afe60..ef5076b5e7027 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -1824,35 +1824,6 @@ static void glk_pipe_scaler_clock_gating_wa(struct drm_i915_private *dev_priv,
> >  	intel_de_write(dev_priv, CLKGATE_DIS_PSL(pipe), val);
> >  }
> >  
> > -static void icl_pipe_mbus_enable(struct intel_crtc *crtc, bool joined_mbus)
> > -{
> > -	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> > -	enum pipe pipe = crtc->pipe;
> > -	u32 val;
> > -
> > -	val = intel_de_read(dev_priv, PIPE_MBUS_DBOX_CTL(pipe));
> > -	val &= ~MBUS_DBOX_A_CREDIT_MASK;
> > -	/* Wa_22010947358:adl-p */
> > -	if (IS_ALDERLAKE_P(dev_priv))
> > -		val |= joined_mbus ? MBUS_DBOX_A_CREDIT(6) : MBUS_DBOX_A_CREDIT(4);
> > -	else
> > -		val |= MBUS_DBOX_A_CREDIT(2);
> > -
> > -	val &= ~(MBUS_DBOX_BW_CREDIT_MASK | MBUS_DBOX_B_CREDIT_MASK);
> > -	if (IS_ALDERLAKE_P(dev_priv)) {
> > -		val |= MBUS_DBOX_BW_CREDIT(2);
> > -		val |= MBUS_DBOX_B_CREDIT(8);
> > -	} else if (DISPLAY_VER(dev_priv) >= 12) {
> > -		val |= MBUS_DBOX_BW_CREDIT(2);
> > -		val |= MBUS_DBOX_B_CREDIT(12);
> > -	} else {
> > -		val |= MBUS_DBOX_BW_CREDIT(1);
> > -		val |= MBUS_DBOX_B_CREDIT(8);
> > -	}
> > -
> > -	intel_de_write(dev_priv, PIPE_MBUS_DBOX_CTL(pipe), val);
> > -}
> > -
> >  static void hsw_set_linetime_wm(const struct intel_crtc_state *crtc_state)
> >  {
> >  	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> > @@ -1988,13 +1959,6 @@ static void hsw_crtc_enable(struct intel_atomic_state *state,
> >  
> >  	intel_initial_watermarks(state, crtc);
> >  
> > -	if (DISPLAY_VER(dev_priv) >= 11) {
> > -		const struct intel_dbuf_state *dbuf_state =
> > -				intel_atomic_get_new_dbuf_state(state);
> > -
> > -		icl_pipe_mbus_enable(crtc, dbuf_state->joined_mbus);
> > -	}
> > -
> >  	if (intel_crtc_is_bigjoiner_slave(new_crtc_state))
> >  		intel_crtc_vblank_on(new_crtc_state);
> >  
> > @@ -8599,6 +8563,7 @@ static void intel_atomic_commit_tail(struct intel_atomic_state *state)
> >  	intel_encoders_update_prepare(state);
> >  
> >  	intel_dbuf_pre_plane_update(state);
> > +	intel_mbus_dbox_update(state);
> >  
> >  	for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
> >  		if (new_crtc_state->do_async_flip)
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > index e60c02d760ffa..cf290bb704221 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -8258,3 +8258,50 @@ void intel_dbuf_post_plane_update(struct intel_atomic_state *state)
> >  	gen9_dbuf_slices_update(dev_priv,
> >  				new_dbuf_state->enabled_slices);
> >  }
> > +
> > +void intel_mbus_dbox_update(struct intel_atomic_state *state)
> > +{
> > +	struct drm_i915_private *i915 = to_i915(state->base.dev);
> > +	struct intel_crtc_state *new_crtc_state;
> > +	struct intel_dbuf_state *new_dbuf_state;
> > +	struct intel_crtc *crtc;
> > +	int i;
> > +
> > +	if (DISPLAY_VER(i915) < 11 || !state->modeset)
> > +		return;
> > +
> > +	if (HAS_MBUS_JOINING(i915))
> > +		new_dbuf_state = intel_atomic_get_dbuf_state(state);
> > +
> > +	for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
> > +		u32 val;
> > +
> > +		if (!new_crtc_state->hw.active ||
> > +		    !intel_crtc_needs_modeset(new_crtc_state))
> > +			continue;
> > +
> > +		val = intel_de_read(i915, PIPE_MBUS_DBOX_CTL(crtc->pipe));
> > +		val &= ~MBUS_DBOX_A_CREDIT_MASK;
> > +		/* Wa_22010947358:adl-p */
> > +		if (IS_ALDERLAKE_P(i915))
> > +			val |= new_dbuf_state->joined_mbus ? MBUS_DBOX_A_CREDIT(6) :
> > +							     MBUS_DBOX_A_CREDIT(4);
> 
> Hmm. I'm not super happy with the assumption that the dbuf state
> is there. When reading this it's not immediately obvious why this
> works.

If there is a modeset it is guarantee that dbuf state will be present in state:


skl_compute_ddb(struct intel_atomic_state *state)
{
	...

	for_each_new_intel_crtc_in_state(state, crtc, new_crtc_state, i) {
		new_dbuf_state = intel_atomic_get_dbuf_state(state);
		if (IS_ERR(new_dbuf_state))
			return PTR_ERR(new_dbuf_state);

		old_dbuf_state = intel_atomic_get_old_dbuf_state(state);
		break;
	}

	if (!new_dbuf_state)
		return 0;





> 
> Might actually be nice to depend purely on the dbuf_state for this
> stuff. So how about something like:
> 
> intel_mbus_dbox_update()
> {
> 	if (!new_dbuf_state ||
> 	    (new_dbuf_state->joined_mbus == old_dbuf_state->joined_mbus &&
> 	     new_dbuf_state->active_pipes == old_dbuf_state->active_pipes))
> 	     return;
> 
> 	for_each_pipe_masked(new_dbuf_state->active_pipes)
> 		write PIPE_MBUS_DBOX_CTL
> }
> 
> ?
> 
> > +			val |= MBUS_DBOX_A_CREDIT(2);
> > +
> > +		if (IS_ALDERLAKE_P(i915)) {
> > +			val |= MBUS_DBOX_BW_CREDIT(2);
> > +			val |= MBUS_DBOX_B_CREDIT(8);
> > +		} else if (DISPLAY_VER(i915) >= 12) {
> > +			val &= ~(MBUS_DBOX_BW_CREDIT_MASK | MBUS_DBOX_B_CREDIT_MASK);
> > +			val |= MBUS_DBOX_BW_CREDIT(2);
> > +			val |= MBUS_DBOX_B_CREDIT(12);
> > +		} else {
> > +			val &= ~(MBUS_DBOX_BW_CREDIT_MASK | MBUS_DBOX_B_CREDIT_MASK);
> > +			val |= MBUS_DBOX_BW_CREDIT(1);
> > +			val |= MBUS_DBOX_B_CREDIT(8);
> > +		}
> > +
> > +		intel_de_write(i915, PIPE_MBUS_DBOX_CTL(crtc->pipe), val);
> > +	}
> > +}
> > diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h
> > index 51705151b842f..50604cf7398c4 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.h
> > +++ b/drivers/gpu/drm/i915/intel_pm.h
> > @@ -94,5 +94,6 @@ intel_atomic_get_dbuf_state(struct intel_atomic_state *state);
> >  int intel_dbuf_init(struct drm_i915_private *dev_priv);
> >  void intel_dbuf_pre_plane_update(struct intel_atomic_state *state);
> >  void intel_dbuf_post_plane_update(struct intel_atomic_state *state);
> > +void intel_mbus_dbox_update(struct intel_atomic_state *state);
> >  
> >  #endif /* __INTEL_PM_H__ */
> > -- 
> > 2.35.1
> 



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