drm/i915: add transcoder enable/disable functions

Along with assertion checks for the FDI transmitters and receivers
(including PLLs).  Modify the pipe enable function to check for FDI PLL
status as well, when driving PCH ports.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/intel_display.c

@@ -1081,6 +1081,84 @@ static void assert_pll(struct drm_i915_private *dev_priv,
 #define assert_pll_enabled(d, p) assert_pll(d, p, true)
 #define assert_pll_disabled(d, p) assert_pll(d, p, false)
 
+/* For ILK+ */
+static void assert_pch_pll(struct drm_i915_private *dev_priv,
+			   enum pipe pipe, bool state)
+{
+	int reg;
+	u32 val;
+	bool cur_state;
+
+	reg = PCH_DPLL(pipe);
+	val = I915_READ(reg);
+	cur_state = !!(val & DPLL_VCO_ENABLE);
+	WARN(cur_state != state,
+	     "PCH PLL state assertion failure (expected %s, current %s)\n",
+	     state_string(state), state_string(cur_state));
+}
+#define assert_pch_pll_enabled(d, p) assert_pch_pll(d, p, true)
+#define assert_pch_pll_disabled(d, p) assert_pch_pll(d, p, false)
+
+static void assert_fdi_tx(struct drm_i915_private *dev_priv,
+			  enum pipe pipe, bool state)
+{
+	int reg;
+	u32 val;
+	bool cur_state;
+
+	reg = FDI_TX_CTL(pipe);
+	val = I915_READ(reg);
+	cur_state = !!(val & FDI_TX_ENABLE);
+	WARN(cur_state != state,
+	     "FDI TX state assertion failure (expected %s, current %s)\n",
+	     state_string(state), state_string(cur_state));
+}
+#define assert_fdi_tx_enabled(d, p) assert_fdi_tx(d, p, true)
+#define assert_fdi_tx_disabled(d, p) assert_fdi_tx(d, p, false)
+
+static void assert_fdi_rx(struct drm_i915_private *dev_priv,
+			  enum pipe pipe, bool state)
+{
+	int reg;
+	u32 val;
+	bool cur_state;
+
+	reg = FDI_RX_CTL(pipe);
+	val = I915_READ(reg);
+	cur_state = !!(val & FDI_RX_ENABLE);
+	WARN(cur_state != state,
+	     "FDI RX state assertion failure (expected %s, current %s)\n",
+	     state_string(state), state_string(cur_state));
+}
+#define assert_fdi_rx_enabled(d, p) assert_fdi_rx(d, p, true)
+#define assert_fdi_rx_disabled(d, p) assert_fdi_rx(d, p, false)
+
+static void assert_fdi_tx_pll_enabled(struct drm_i915_private *dev_priv,
+				      enum pipe pipe)
+{
+	int reg;
+	u32 val;
+
+	/* ILK FDI PLL is always enabled */
+	if (dev_priv->info->gen == 5)
+		return;
+
+	reg = FDI_TX_CTL(pipe);
+	val = I915_READ(reg);
+	WARN(!(val & FDI_TX_PLL_ENABLE), "FDI TX PLL assertion failure, should be active but is disabled\n");
+}
+
+static void assert_fdi_rx_pll_enabled(struct drm_i915_private *dev_priv,
+				      enum pipe pipe)
+{
+	int reg;
+	u32 val;
+
+	reg = FDI_RX_CTL(pipe);
+	val = I915_READ(reg);
+	WARN(!(val & FDI_RX_PLL_ENABLE), "FDI RX PLL assertion failure, should be active but is disabled\n");
+}
+
 static void assert_panel_unlocked(struct drm_i915_private *dev_priv,
 				  enum pipe pipe)
 {
@@ -1298,10 +1376,59 @@ static void intel_disable_pch_pll(struct drm_i915_private *dev_priv,
 	udelay(200);
 }
 
+static void intel_enable_transcoder(struct drm_i915_private *dev_priv,
+				    enum pipe pipe)
+{
+	int reg;
+	u32 val;
+
+	/* PCH only available on ILK+ */
+	BUG_ON(dev_priv->info->gen < 5);
+
+	/* Make sure PCH DPLL is enabled */
+	assert_pch_pll_enabled(dev_priv, pipe);
+
+	/* FDI must be feeding us bits for PCH ports */
+	assert_fdi_tx_enabled(dev_priv, pipe);
+	assert_fdi_rx_enabled(dev_priv, pipe);
+
+	reg = TRANSCONF(pipe);
+	val = I915_READ(reg);
+	/*
+	 * make the BPC in transcoder be consistent with
+	 * that in pipeconf reg.
+	 */
+	val &= ~PIPE_BPC_MASK;
+	val |= I915_READ(PIPECONF(pipe)) & PIPE_BPC_MASK;
+	I915_WRITE(reg, val | TRANS_ENABLE);
+	if (wait_for(I915_READ(reg) & TRANS_STATE_ENABLE, 100))
+		DRM_ERROR("failed to enable transcoder %d\n", pipe);
+}
+
+static void intel_disable_transcoder(struct drm_i915_private *dev_priv,
+				     enum pipe pipe)
+{
+	int reg;
+	u32 val;
+
+	/* FDI relies on the transcoder */
+	assert_fdi_tx_disabled(dev_priv, pipe);
+	assert_fdi_rx_disabled(dev_priv, pipe);
+
+	reg = TRANSCONF(pipe);
+	val = I915_READ(reg);
+	val &= ~TRANS_ENABLE;
+	I915_WRITE(reg, val);
+	/* wait for PCH transcoder off, transcoder state */
+	if (wait_for((I915_READ(reg) & TRANS_STATE_ENABLE) == 0, 50))
+		DRM_ERROR("failed to disable transcoder\n");
+}
+
 /**
  * intel_enable_pipe - enable a pipe, assertiing requirements
  * @dev_priv: i915 private structure
  * @pipe: pipe to enable
+ * @pch_port: on ILK+, is this pipe driving a PCH port or not
  *
  * Enable @pipe, making sure that various hardware specific requirements
  * are met, if applicable, e.g. PLL enabled, LVDS pairs enabled, etc.
@@ -1311,7 +1438,8 @@ static void intel_disable_pch_pll(struct drm_i915_private *dev_priv,
  * Will wait until the pipe is actually running (i.e. first vblank) before
  * returning.
  */
-static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe)
+static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe,
+			      bool pch_port)
 {
 	int reg;
 	u32 val;
@@ -1323,6 +1451,14 @@ static void intel_enable_pipe(struct drm_i915_private *dev_priv, enum pipe pipe)
 	 */
 	if (!HAS_PCH_SPLIT(dev_priv->dev))
 		assert_pll_enabled(dev_priv, pipe);
+	else {
+		if (pch_port) {
+			/* if driving the PCH, we need FDI enabled */
+			assert_fdi_rx_pll_enabled(dev_priv, pipe);
+			assert_fdi_tx_pll_enabled(dev_priv, pipe);
+		}
+		/* FIXME: assert CPU port conditions for SNB+ */
+	}
 
 	reg = PIPECONF(pipe);
 	val = I915_READ(reg);
@@ -2385,6 +2521,31 @@ static void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc)
 		   atomic_read(&obj->pending_flip) == 0);
 }
 
+static bool intel_crtc_driving_pch(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_mode_config *mode_config = &dev->mode_config;
+	struct intel_encoder *encoder;
+
+	/*
+	 * If there's a non-PCH eDP on this crtc, it must be DP_A, and that
+	 * must be driven by its own crtc; no sharing is possible.
+	 */
+	list_for_each_entry(encoder, &mode_config->encoder_list, base.head) {
+		if (encoder->base.crtc != crtc)
+			continue;
+
+		switch (encoder->type) {
+		case INTEL_OUTPUT_EDP:
+			if (!intel_encoder_is_pch_edp(&encoder->base))
+				return false;
+			continue;
+		}
+	}
+
+	return true;
+}
+
 static void ironlake_crtc_enable(struct drm_crtc *crtc)
 {
 	struct drm_device *dev = crtc->dev;
@@ -2393,6 +2554,7 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 	int pipe = intel_crtc->pipe;
 	int plane = intel_crtc->plane;
 	u32 reg, temp;
+	bool is_pch_port;
 
 	if (intel_crtc->active)
 		return;
@@ -2423,7 +2585,9 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 			   dev_priv->pch_pf_size);
 	}
 
-	intel_enable_pipe(dev_priv, pipe);
+	is_pch_port = intel_crtc_driving_pch(crtc);
+
+	intel_enable_pipe(dev_priv, pipe, is_pch_port);
 	intel_enable_plane(dev_priv, plane, pipe);
 
 	/* For PCH output, training FDI link */
@@ -2492,18 +2656,7 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 		I915_WRITE(reg, temp);
 	}
 
-	/* enable PCH transcoder */
-	reg = TRANSCONF(pipe);
-	temp = I915_READ(reg);
-	/*
-	 * make the BPC in transcoder be consistent with
-	 * that in pipeconf reg.
-	 */
-	temp &= ~PIPE_BPC_MASK;
-	temp |= I915_READ(PIPECONF(pipe)) & PIPE_BPC_MASK;
-	I915_WRITE(reg, temp | TRANS_ENABLE);
-	if (wait_for(I915_READ(reg) & TRANS_STATE_ENABLE, 100))
-		DRM_ERROR("failed to enable transcoder %d\n", pipe);
+	intel_enable_transcoder(dev_priv, pipe);
 
 	intel_crtc_load_lut(crtc);
 	intel_update_fbc(dev);
@@ -2592,15 +2745,7 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc)
 		}
 	}
 
-	/* disable PCH transcoder */
-	reg = TRANSCONF(plane);
-	temp = I915_READ(reg);
-	if (temp & TRANS_ENABLE) {
-		I915_WRITE(reg, temp & ~TRANS_ENABLE);
-		/* wait for PCH transcoder off, transcoder state */
-		if (wait_for((I915_READ(reg) & TRANS_STATE_ENABLE) == 0, 50))
-			DRM_ERROR("failed to disable transcoder\n");
-	}
+	intel_disable_transcoder(dev_priv, pipe);
 
 	if (HAS_PCH_CPT(dev)) {
 		/* disable TRANS_DP_CTL */
@@ -2702,7 +2847,7 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 	intel_update_watermarks(dev);
 
 	intel_enable_pll(dev_priv, pipe);
-	intel_enable_pipe(dev_priv, pipe);
+	intel_enable_pipe(dev_priv, pipe, false);
 	intel_enable_plane(dev_priv, plane, pipe);
 
 	intel_crtc_load_lut(crtc);
@@ -4688,7 +4833,7 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 	I915_WRITE(PIPECONF(pipe), pipeconf);
 	POSTING_READ(PIPECONF(pipe));
 	if (!HAS_PCH_SPLIT(dev))
-		intel_enable_pipe(dev_priv, pipe);
+		intel_enable_pipe(dev_priv, pipe, false);
 
 	intel_wait_for_vblank(dev, pipe);