drm/i915: Fix frame start delay programming

Currently we're blindly poking at the frame start delay bits
in PIPECONF when trying to sanitize the hardware state. Those
bits decided to move elsewhere on HSW, so on many platforms
we're not doing anything at all here. Also we're forgetting
about the PCH transcoder entirely.

Add all the bit definitions for the various homes these bits
have had throughout the years, and reset them all to zero.

However I'm not entirely sure this is a safe thing to do. If
not I guess we'd want full readout+statecheck for this stuff.
For now let's stick to the current logic and hope for the
best.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191024122138.25065-3-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

1 files changed, 88 insertions, 13 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index c382498f081e..1558aefc2fd9 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -1674,11 +1674,16 @@ static void ironlake_enable_pch_transcoder(const struct intel_crtc_state *crtc_s
 	assert_fdi_rx_enabled(dev_priv, pipe);
 
 	if (HAS_PCH_CPT(dev_priv)) {
-		/* Workaround: Set the timing override bit before enabling the
-		 * pch transcoder. */
 		reg = TRANS_CHICKEN2(pipe);
 		val = I915_READ(reg);
+		/*
+		 * Workaround: Set the timing override bit
+		 * before enabling the pch transcoder.
+		 */
 		val |= TRANS_CHICKEN2_TIMING_OVERRIDE;
+		/* Configure frame start delay to match the CPU */
+		val &= ~TRANS_CHICKEN2_FRAME_START_DELAY_MASK;
+		val |= TRANS_CHICKEN2_FRAME_START_DELAY(0);
 		I915_WRITE(reg, val);
 	}
 
@@ -1687,6 +1692,10 @@ static void ironlake_enable_pch_transcoder(const struct intel_crtc_state *crtc_s
 	pipeconf_val = I915_READ(PIPECONF(pipe));
 
 	if (HAS_PCH_IBX(dev_priv)) {
+		/* Configure frame start delay to match the CPU */
+		val &= ~TRANS_FRAME_START_DELAY_MASK;
+		val |= TRANS_FRAME_START_DELAY(0);
+
 		/*
 		 * Make the BPC in transcoder be consistent with
 		 * that in pipeconf reg. For HDMI we must use 8bpc
@@ -1724,9 +1733,12 @@ static void lpt_enable_pch_transcoder(struct drm_i915_private *dev_priv,
 	assert_fdi_tx_enabled(dev_priv, (enum pipe) cpu_transcoder);
 	assert_fdi_rx_enabled(dev_priv, PIPE_A);
 
-	/* Workaround: set timing override bit. */
 	val = I915_READ(TRANS_CHICKEN2(PIPE_A));
+	/* Workaround: set timing override bit. */
 	val |= TRANS_CHICKEN2_TIMING_OVERRIDE;
+	/* Configure frame start delay to match the CPU */
+	val &= ~TRANS_CHICKEN2_FRAME_START_DELAY_MASK;
+	val |= TRANS_CHICKEN2_FRAME_START_DELAY(0);
 	I915_WRITE(TRANS_CHICKEN2(PIPE_A), val);
 
 	val = TRANS_ENABLE;
@@ -6583,6 +6595,19 @@ static void icl_pipe_mbus_enable(struct intel_crtc *crtc)
 	I915_WRITE(PIPE_MBUS_DBOX_CTL(pipe), val);
 }
 
+static void hsw_set_frame_start_delay(const struct intel_crtc_state *crtc_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	i915_reg_t reg = CHICKEN_TRANS(crtc_state->cpu_transcoder);
+	u32 val;
+
+	val = I915_READ(reg);
+	val &= ~HSW_FRAME_START_DELAY_MASK;
+	val |= HSW_FRAME_START_DELAY(0);
+	I915_WRITE(reg, val);
+}
+
 static void haswell_crtc_enable(struct intel_crtc_state *pipe_config,
 				struct intel_atomic_state *state)
 {
@@ -6625,8 +6650,10 @@ static void haswell_crtc_enable(struct intel_crtc_state *pipe_config,
 					     &pipe_config->fdi_m_n, NULL);
 	}
 
-	if (!transcoder_is_dsi(cpu_transcoder))
+	if (!transcoder_is_dsi(cpu_transcoder)) {
+		hsw_set_frame_start_delay(pipe_config);
 		haswell_set_pipeconf(pipe_config);
+	}
 
 	if (INTEL_GEN(dev_priv) >= 9 || IS_BROADWELL(dev_priv))
 		bdw_set_pipemisc(pipe_config);
@@ -8523,6 +8550,8 @@ static void i9xx_set_pipeconf(const struct intel_crtc_state *crtc_state)
 
 	pipeconf |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
 
+	pipeconf |= PIPECONF_FRAME_START_DELAY(0);
+
 	I915_WRITE(PIPECONF(crtc->pipe), pipeconf);
 	POSTING_READ(PIPECONF(crtc->pipe));
 }
@@ -9604,6 +9633,8 @@ static void ironlake_set_pipeconf(const struct intel_crtc_state *crtc_state)
 
 	val |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
 
+	val |= PIPECONF_FRAME_START_DELAY(0);
+
 	I915_WRITE(PIPECONF(pipe), val);
 	POSTING_READ(PIPECONF(pipe));
 }
@@ -17202,25 +17233,69 @@ static bool has_pch_trancoder(struct drm_i915_private *dev_priv,
 		(HAS_PCH_LPT_H(dev_priv) && pch_transcoder == PIPE_A);
 }
 
-static void intel_sanitize_crtc(struct intel_crtc *crtc,
-				struct drm_modeset_acquire_ctx *ctx)
+static void intel_sanitize_frame_start_delay(const struct intel_crtc_state *crtc_state)
 {
-	struct drm_device *dev = crtc->base.dev;
-	struct drm_i915_private *dev_priv = to_i915(dev);
-	struct intel_crtc_state *crtc_state = to_intel_crtc_state(crtc->base.state);
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 
-	/* Clear any frame start delays used for debugging left by the BIOS */
-	if (crtc->active && !transcoder_is_dsi(cpu_transcoder)) {
+	if (INTEL_GEN(dev_priv) >= 9 ||
+	    IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv)) {
+		i915_reg_t reg = CHICKEN_TRANS(cpu_transcoder);
+		u32 val;
+
+		if (transcoder_is_dsi(cpu_transcoder))
+			return;
+
+		val = I915_READ(reg);
+		val &= ~HSW_FRAME_START_DELAY_MASK;
+		val |= HSW_FRAME_START_DELAY(0);
+		I915_WRITE(reg, val);
+	} else {
 		i915_reg_t reg = PIPECONF(cpu_transcoder);
+		u32 val;
+
+		val = I915_READ(reg);
+		val &= ~PIPECONF_FRAME_START_DELAY_MASK;
+		val |= PIPECONF_FRAME_START_DELAY(0);
+		I915_WRITE(reg, val);
+	}
+
+	if (!crtc_state->has_pch_encoder)
+		return;
+
+	if (HAS_PCH_IBX(dev_priv)) {
+		i915_reg_t reg = PCH_TRANSCONF(crtc->pipe);
+		u32 val;
+
+		val = I915_READ(reg);
+		val &= ~TRANS_FRAME_START_DELAY_MASK;
+		val |= TRANS_FRAME_START_DELAY(0);
+		I915_WRITE(reg, val);
+	} else {
+		i915_reg_t reg = TRANS_CHICKEN2(crtc->pipe);
+		u32 val;
 
-		I915_WRITE(reg,
-			   I915_READ(reg) & ~PIPECONF_FRAME_START_DELAY_MASK);
+		val = I915_READ(reg);
+		val &= ~TRANS_CHICKEN2_FRAME_START_DELAY_MASK;
+		val |= TRANS_CHICKEN2_FRAME_START_DELAY(0);
+		I915_WRITE(reg, val);
 	}
+}
+
+static void intel_sanitize_crtc(struct intel_crtc *crtc,
+				struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_device *dev = crtc->base.dev;
+	struct drm_i915_private *dev_priv = to_i915(dev);
+	struct intel_crtc_state *crtc_state = to_intel_crtc_state(crtc->base.state);
 
 	if (crtc_state->hw.active) {
 		struct intel_plane *plane;
 
+		/* Clear any frame start delays used for debugging left by the BIOS */
+		intel_sanitize_frame_start_delay(crtc_state);
+
 		/* Disable everything but the primary plane */
 		for_each_intel_plane_on_crtc(dev, crtc, plane) {
 			const struct intel_plane_state *plane_state =