[Intel-gfx] [PATCH 36/37] drm/i915: add warning when using old bits on Haswell/LPT

[Eugeni Dodonov]

Those have different functionality on Haswell architecture, so let's
trigger a warning message when we are going through a path we should not
go into on Haswell.

This patch is here for make debugging and log tracing easier, it should
go away in the future, we we'll stop hitting those code paths.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov at intel.com>
---
 drivers/gpu/drm/i915/intel_display.c |   59 +++++++++++++++++++++++++++-------
 1 file changed, 47 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a37e0b7..10b92e8 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -847,9 +847,16 @@ static void assert_fdi_tx(struct drm_i915_private *dev_priv,
 	u32 val;
 	bool cur_state;
 
-	reg = FDI_TX_CTL(pipe);
-	val = I915_READ(reg);
-	cur_state = !!(val & FDI_TX_ENABLE);
+	if (IS_HASWELL(dev_priv->dev)) {
+		DRM_ERROR("Attempting to check FDI_TX_CTL on Haswell, using DDI instead\n");
+		reg = DDI_FUNC_CTL(pipe);
+		val = I915_READ(reg);
+		cur_state = !!(val & PIPE_DDI_FUNC_ENABLE);
+	} else {
+		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));
@@ -864,9 +871,14 @@ static void assert_fdi_rx(struct drm_i915_private *dev_priv,
 	u32 val;
 	bool cur_state;
 
-	reg = FDI_RX_CTL(pipe);
-	val = I915_READ(reg);
-	cur_state = !!(val & FDI_RX_ENABLE);
+	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
+			DRM_ERROR("Attempting to enable FDI_RX on Haswell pipe > 0\n");
+			return;
+	} else {
+		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));
@@ -884,6 +896,11 @@ static void assert_fdi_tx_pll_enabled(struct drm_i915_private *dev_priv,
 	if (dev_priv->info->gen == 5)
 		return;
 
+	if (IS_HASWELL(dev_priv->dev)) {
+		DRM_ERROR("Attempting to check FDI_TX_PLL on Haswell, aborting\n");
+		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");
@@ -895,6 +912,10 @@ static void assert_fdi_rx_pll_enabled(struct drm_i915_private *dev_priv,
 	int reg;
 	u32 val;
 
+	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
+		DRM_ERROR("Attempting to enable FDI on Haswell with pipe > 0\n");
+		return;
+	}
 	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");
@@ -1000,6 +1021,11 @@ static void assert_pch_refclk_enabled(struct drm_i915_private *dev_priv)
 	u32 val;
 	bool enabled;
 
+	if (HAS_PCH_LPT(dev_priv->dev)) {
+		DRM_ERROR("LPT does not has PCH refclk, skipping check\n");
+		return;
+	}
+
 	val = I915_READ(PCH_DREF_CONTROL);
 	enabled = !!(val & (DREF_SSC_SOURCE_MASK | DREF_NONSPREAD_SOURCE_MASK |
 			    DREF_SUPERSPREAD_SOURCE_MASK));
@@ -1323,6 +1349,10 @@ static void intel_enable_transcoder(struct drm_i915_private *dev_priv,
 	assert_fdi_tx_enabled(dev_priv, pipe);
 	assert_fdi_rx_enabled(dev_priv, pipe);
 
+	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
+		DRM_ERROR("Attempting to enable FDI on Haswell with pipe > 0\n");
+		return;
+	}
 	reg = TRANSCONF(pipe);
 	val = I915_READ(reg);
 	pipeconf_val = I915_READ(PIPECONF(pipe));
@@ -3308,13 +3338,18 @@ static void ironlake_fdi_pll_enable(struct drm_crtc *crtc)
 	udelay(200);
 
 	/* Enable CPU FDI TX PLL, always on for Ironlake */
-	reg = FDI_TX_CTL(pipe);
-	temp = I915_READ(reg);
-	if ((temp & FDI_TX_PLL_ENABLE) == 0) {
-		I915_WRITE(reg, temp | FDI_TX_PLL_ENABLE);
+	if (IS_HASWELL(dev)) {
+		DRM_ERROR("Skipping enablement of FDI_TX_PLL on Haswell\n");
+		return;
+	} else {
+		reg = FDI_TX_CTL(pipe);
+		temp = I915_READ(reg);
+		if ((temp & FDI_TX_PLL_ENABLE) == 0) {
+			I915_WRITE(reg, temp | FDI_TX_PLL_ENABLE);
 
-		POSTING_READ(reg);
-		udelay(100);
+			POSTING_READ(reg);
+			udelay(100);
+		}
 	}
 }
 
-- 
1.7.9.2