drm/i915: Enable FBC at Haswell.

This patch introduce Frame Buffer Compression (FBC) support for HSW.
FBC is tied to primary plane A in HSW.

v2: Ville pointed out docs say FBC must be disabled before disabling
    the plane on HSW.
v3: Really enabling it by default at HSW.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.c

@@ -319,6 +319,7 @@ static const struct intel_device_info intel_haswell_m_info = {
 	.is_mobile = 1,
 	.has_ddi = 1,
 	.has_fpga_dbg = 1,
+	.has_fbc = 1,
 };
 
 static const struct pci_device_id pciidlist[] = {		/* aka */

drivers/gpu/drm/i915/intel_display.c

@@ -3518,11 +3518,12 @@ static void haswell_crtc_disable(struct drm_crtc *crtc)
 	drm_vblank_off(dev, pipe);
 	intel_crtc_update_cursor(crtc, false);
 
-	intel_disable_plane(dev_priv, plane, pipe);
-
+	/* FBC must be disabled before disabling the plane on HSW. */
 	if (dev_priv->cfb_plane == plane)
 		intel_disable_fbc(dev);
 
+	intel_disable_plane(dev_priv, plane, pipe);
+
 	if (intel_crtc->config.has_pch_encoder)
 		intel_set_pch_fifo_underrun_reporting(dev, TRANSCODER_A, false);
 	intel_disable_pipe(dev_priv, pipe);

drivers/gpu/drm/i915/intel_pm.c

@@ -274,12 +274,14 @@ static void gen7_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
 		   IVB_DPFC_CTL_FENCE_EN |
 		   intel_crtc->plane << IVB_DPFC_CTL_PLANE_SHIFT);
 
-	/* WaFbcAsynchFlipDisableFbcQueue */
-	I915_WRITE(ILK_DISPLAY_CHICKEN1, ILK_FBCQ_DIS);
-	/* WaFbcDisableDpfcClockGating */
-	I915_WRITE(ILK_DSPCLK_GATE_D,
-		   I915_READ(ILK_DSPCLK_GATE_D) |
-		   ILK_DPFCUNIT_CLOCK_GATE_DISABLE);
+	if (IS_IVYBRIDGE(dev)) {
+		/* WaFbcAsynchFlipDisableFbcQueue */
+		I915_WRITE(ILK_DISPLAY_CHICKEN1, ILK_FBCQ_DIS);
+		/* WaFbcDisableDpfcClockGating */
+		I915_WRITE(ILK_DSPCLK_GATE_D,
+			   I915_READ(ILK_DSPCLK_GATE_D) |
+			   ILK_DPFCUNIT_CLOCK_GATE_DISABLE);
+	}
 
 	I915_WRITE(SNB_DPFC_CTL_SA,
 		   SNB_CPU_FENCE_ENABLE | obj->fence_reg);
@@ -476,7 +478,7 @@ void intel_update_fbc(struct drm_device *dev)
 	if (enable_fbc < 0) {
 		DRM_DEBUG_KMS("fbc set to per-chip default\n");
 		enable_fbc = 1;
-		if (INTEL_INFO(dev)->gen <= 7)
+		if (INTEL_INFO(dev)->gen <= 7 && !IS_HASWELL(dev))
 			enable_fbc = 0;
 	}
 	if (!enable_fbc) {
@@ -497,7 +499,8 @@ void intel_update_fbc(struct drm_device *dev)
 		dev_priv->no_fbc_reason = FBC_MODE_TOO_LARGE;
 		goto out_disable;
 	}
-	if ((IS_I915GM(dev) || IS_I945GM(dev)) && intel_crtc->plane != 0) {
+	if ((IS_I915GM(dev) || IS_I945GM(dev) || IS_HASWELL(dev)) &&
+	    intel_crtc->plane != 0) {
 		DRM_DEBUG_KMS("plane not 0, disabling compression\n");
 		dev_priv->no_fbc_reason = FBC_BAD_PLANE;
 		goto out_disable;
@@ -4544,7 +4547,7 @@ void intel_init_pm(struct drm_device *dev)
 	if (I915_HAS_FBC(dev)) {
 		if (HAS_PCH_SPLIT(dev)) {
 			dev_priv->display.fbc_enabled = ironlake_fbc_enabled;
-			if (IS_IVYBRIDGE(dev))
+			if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev))
 				dev_priv->display.enable_fbc =
 					gen7_enable_fbc;
 			else