drm/i915: Move the encoder vs. FDI dotclock check out from encoder .get_config()

Currently we check if the encoder's idea of dotclock agrees with what
we calculated based on the FDI parameters. We do this in the encoder
.get_config() hooks, which isn't so nice in case the BIOS (or some other
outside party) made a mess of the state and we're just trying to take
over.

So as a prep step to being able sanitize such a bogus state, move the
the sanity check to just after we've read out the entire state. If
we then need to sanitize a bad state, it should be easier to move the
sanity check to occur after sanitation instead of before it.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455738073-14502-3-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>

drivers/gpu/drm/i915/intel_crt.c

@@ -120,17 +120,9 @@ static unsigned int intel_crt_get_flags(struct intel_encoder *encoder)
 static void intel_crt_get_config(struct intel_encoder *encoder,
 				 struct intel_crtc_state *pipe_config)
 {
-	struct drm_device *dev = encoder->base.dev;
-	int dotclock;
-
 	pipe_config->base.adjusted_mode.flags |= intel_crt_get_flags(encoder);
 
-	dotclock = pipe_config->port_clock;
-
-	if (HAS_PCH_SPLIT(dev))
-		ironlake_check_encoder_dotclock(pipe_config, dotclock);
-
-	pipe_config->base.adjusted_mode.crtc_clock = dotclock;
+	pipe_config->base.adjusted_mode.crtc_clock = pipe_config->port_clock;
 }
 
 static void hsw_crt_get_config(struct intel_encoder *encoder,

drivers/gpu/drm/i915/intel_display.c

@@ -224,12 +224,11 @@ static void intel_update_czclk(struct drm_i915_private *dev_priv)
 }
 
 static inline u32 /* units of 100MHz */
-intel_fdi_link_freq(struct drm_device *dev)
+intel_fdi_link_freq(struct drm_i915_private *dev_priv)
 {
-	if (IS_GEN5(dev)) {
-		struct drm_i915_private *dev_priv = dev->dev_private;
+	if (IS_GEN5(dev_priv))
 		return (I915_READ(FDI_PLL_BIOS_0) & FDI_PLL_FB_CLOCK_MASK) + 2;
-	} else
+	else
 		return 27;
 }
 
@@ -6680,7 +6679,7 @@ retry:
 	 * Hence the bw of each lane in terms of the mode signal
 	 * is:
 	 */
-	link_bw = intel_fdi_link_freq(dev) * MHz(100)/KHz(1)/10;
+	link_bw = intel_fdi_link_freq(to_i915(dev)) * MHz(100)/KHz(1)/10;
 
 	fdi_dotclock = adjusted_mode->crtc_clock;
 
@@ -6692,8 +6691,7 @@ retry:
 	intel_link_compute_m_n(pipe_config->pipe_bpp, lane, fdi_dotclock,
 			       link_bw, &pipe_config->fdi_m_n);
 
-	ret = ironlake_check_fdi_lanes(intel_crtc->base.dev,
-				       intel_crtc->pipe, pipe_config);
+	ret = ironlake_check_fdi_lanes(dev, intel_crtc->pipe, pipe_config);
 	if (ret == -EINVAL && pipe_config->pipe_bpp > 6*3) {
 		pipe_config->pipe_bpp -= 2*3;
 		DRM_DEBUG_KMS("fdi link bw constraint, reducing pipe bpp to %i\n",
@@ -10831,19 +10829,18 @@ int intel_dotclock_calculate(int link_freq,
 static void ironlake_pch_clock_get(struct intel_crtc *crtc,
 				   struct intel_crtc_state *pipe_config)
 {
-	struct drm_device *dev = crtc->base.dev;
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 
 	/* read out port_clock from the DPLL */
 	i9xx_crtc_clock_get(crtc, pipe_config);
 
 	/*
-	 * This value does not include pixel_multiplier.
-	 * We will check that port_clock and adjusted_mode.crtc_clock
-	 * agree once we know their relationship in the encoder's
-	 * get_config() function.
+	 * In case there is an active pipe without active ports,
+	 * we may need some idea for the dotclock anyway.
+	 * Calculate one based on the FDI configuration.
 	 */
 	pipe_config->base.adjusted_mode.crtc_clock =
-		intel_dotclock_calculate(intel_fdi_link_freq(dev) * 10000,
+		intel_dotclock_calculate(intel_fdi_link_freq(dev_priv) * 10000,
 					 &pipe_config->fdi_m_n);
 }
 
@@ -12872,6 +12869,24 @@ intel_pipe_config_compare(struct drm_device *dev,
 	return ret;
 }
 
+static void intel_pipe_config_sanity_check(struct drm_i915_private *dev_priv,
+					   const struct intel_crtc_state *pipe_config)
+{
+	if (pipe_config->has_pch_encoder) {
+		int fdi_dotclock = intel_dotclock_calculate(intel_fdi_link_freq(dev_priv) * 10000,
+							    &pipe_config->fdi_m_n);
+		int dotclock = pipe_config->base.adjusted_mode.crtc_clock;
+
+		/*
+		 * FDI already provided one idea for the dotclock.
+		 * Yell if the encoder disagrees.
+		 */
+		WARN(!intel_fuzzy_clock_check(fdi_dotclock, dotclock),
+		     "FDI dotclock and encoder dotclock mismatch, fdi: %i, encoder: %i\n",
+		     fdi_dotclock, dotclock);
+	}
+}
+
 static void check_wm_state(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -13045,6 +13060,8 @@ check_crtc_state(struct drm_device *dev, struct drm_atomic_state *old_state)
 		if (!crtc->state->active)
 			continue;
 
+		intel_pipe_config_sanity_check(dev_priv, pipe_config);
+
 		sw_config = to_intel_crtc_state(crtc->state);
 		if (!intel_pipe_config_compare(dev, sw_config,
 					       pipe_config, false)) {
@@ -13117,18 +13134,6 @@ intel_modeset_check_state(struct drm_device *dev,
 	check_shared_dpll_state(dev);
 }
 
-void ironlake_check_encoder_dotclock(const struct intel_crtc_state *pipe_config,
-				     int dotclock)
-{
-	/*
-	 * FDI already provided one idea for the dotclock.
-	 * Yell if the encoder disagrees.
-	 */
-	WARN(!intel_fuzzy_clock_check(pipe_config->base.adjusted_mode.crtc_clock, dotclock),
-	     "FDI dotclock and encoder dotclock mismatch, fdi: %i, encoder: %i\n",
-	     pipe_config->base.adjusted_mode.crtc_clock, dotclock);
-}
-
 static void update_scanline_offset(struct intel_crtc *crtc)
 {
 	struct drm_device *dev = crtc->base.dev;
@@ -16034,6 +16039,8 @@ static void intel_modeset_readout_hw_state(struct drm_device *dev)
 			drm_calc_timestamping_constants(&crtc->base, &crtc->base.hwmode);
 			update_scanline_offset(crtc);
 		}
+
+		intel_pipe_config_sanity_check(dev_priv, crtc->config);
 	}
 }
 

drivers/gpu/drm/i915/intel_dp.c

@@ -2422,7 +2422,6 @@ static void intel_dp_get_config(struct intel_encoder *encoder,
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum port port = dp_to_dig_port(intel_dp)->port;
 	struct intel_crtc *crtc = to_intel_crtc(encoder->base.crtc);
-	int dotclock;
 
 	tmp = I915_READ(intel_dp->output_reg);
 
@@ -2472,13 +2471,9 @@ static void intel_dp_get_config(struct intel_encoder *encoder,
 			pipe_config->port_clock = 270000;
 	}
 
-	dotclock = intel_dotclock_calculate(pipe_config->port_clock,
-					    &pipe_config->dp_m_n);
-
-	if (HAS_PCH_SPLIT(dev_priv->dev) && port != PORT_A)
-		ironlake_check_encoder_dotclock(pipe_config, dotclock);
-
-	pipe_config->base.adjusted_mode.crtc_clock = dotclock;
+	pipe_config->base.adjusted_mode.crtc_clock =
+		intel_dotclock_calculate(pipe_config->port_clock,
+					 &pipe_config->dp_m_n);
 
 	if (is_edp(intel_dp) && dev_priv->vbt.edp_bpp &&
 	    pipe_config->pipe_bpp > dev_priv->vbt.edp_bpp) {

drivers/gpu/drm/i915/intel_drv.h

@@ -1219,9 +1219,6 @@ void intel_dp_get_m_n(struct intel_crtc *crtc,
 		      struct intel_crtc_state *pipe_config);
 void intel_dp_set_m_n(struct intel_crtc *crtc, enum link_m_n_set m_n);
 int intel_dotclock_calculate(int link_freq, const struct intel_link_m_n *m_n);
-void
-ironlake_check_encoder_dotclock(const struct intel_crtc_state *pipe_config,
-				int dotclock);
 bool bxt_find_best_dpll(struct intel_crtc_state *crtc_state, int target_clock,
 			intel_clock_t *best_clock);
 int chv_calc_dpll_params(int refclk, intel_clock_t *pll_clock);

drivers/gpu/drm/i915/intel_hdmi.c

@@ -952,9 +952,6 @@ static void intel_hdmi_get_config(struct intel_encoder *encoder,
 	if (pipe_config->pixel_multiplier)
 		dotclock /= pipe_config->pixel_multiplier;
 
-	if (HAS_PCH_SPLIT(dev_priv->dev))
-		ironlake_check_encoder_dotclock(pipe_config, dotclock);
-
 	pipe_config->base.adjusted_mode.crtc_clock = dotclock;
 }
 

drivers/gpu/drm/i915/intel_lvds.c

@@ -109,7 +109,6 @@ static void intel_lvds_get_config(struct intel_encoder *encoder,
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
 	u32 tmp, flags = 0;
-	int dotclock;
 
 	tmp = I915_READ(lvds_encoder->reg);
 	if (tmp & LVDS_HSYNC_POLARITY)
@@ -130,12 +129,7 @@ static void intel_lvds_get_config(struct intel_encoder *encoder,
 		pipe_config->gmch_pfit.control |= tmp & PANEL_8TO6_DITHER_ENABLE;
 	}
 
-	dotclock = pipe_config->port_clock;
-
-	if (HAS_PCH_SPLIT(dev_priv->dev))
-		ironlake_check_encoder_dotclock(pipe_config, dotclock);
-
-	pipe_config->base.adjusted_mode.crtc_clock = dotclock;
+	pipe_config->base.adjusted_mode.crtc_clock = pipe_config->port_clock;
 }
 
 static void intel_pre_enable_lvds(struct intel_encoder *encoder)

drivers/gpu/drm/i915/intel_sdvo.c

@@ -1398,12 +1398,10 @@ static void intel_sdvo_get_config(struct intel_encoder *encoder,
 	}
 
 	dotclock = pipe_config->port_clock;
+
 	if (pipe_config->pixel_multiplier)
 		dotclock /= pipe_config->pixel_multiplier;
 
-	if (HAS_PCH_SPLIT(dev))
-		ironlake_check_encoder_dotclock(pipe_config, dotclock);
-
 	pipe_config->base.adjusted_mode.crtc_clock = dotclock;
 
 	/* Cross check the port pixel multiplier with the sdvo encoder state. */