[PATCH 2/2] drm/i915: Add frame buffer compression on Sandybridge

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

Add frame buffer compression on Sandybridge. The method is similar to
Ironlake, except that two new registers of type GTTMMADR must be written
with the right fence info.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_dma.c      |    4 ++--
 drivers/gpu/drm/i915/i915_drv.c      |    1 +
 drivers/gpu/drm/i915/i915_reg.h      |   12 ++++++++++++
 drivers/gpu/drm/i915/intel_display.c |    8 +++++++-
 4 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index e9fb895..3f7b203 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1078,7 +1078,7 @@ static void i915_setup_compression(struct drm_device *dev, int size)
 	if (!cfb_base)
 		goto err_fb;
 
-	if (!(IS_GM45(dev) || IS_IRONLAKE_M(dev))) {
+	if (!(IS_GM45(dev) || HAS_PCH_SPLIT(dev))) {
 		compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
 						    4096, 4096, 0);
 		if (compressed_llb)
@@ -1096,7 +1096,7 @@ static void i915_setup_compression(struct drm_device *dev, int size)
 
 	intel_disable_fbc(dev);
 	dev_priv->compressed_fb = compressed_fb;
-	if (IS_IRONLAKE_M(dev))
+	if (HAS_PCH_SPLIT(dev))
 		I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
 	else if (IS_GM45(dev)) {
 		I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 5f20cd9..bdb29b2 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -165,6 +165,7 @@ static const struct intel_device_info intel_sandybridge_d_info = {
 static const struct intel_device_info intel_sandybridge_m_info = {
 	.gen = 6, .is_mobile = 1,
 	.need_gfx_hws = 1, .has_hotplug = 1,
+	.has_fbc = 1,
 	.has_bsd_ring = 1,
 	.has_blt_ring = 1,
 };
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 5bba63a..811aeb4 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -599,6 +599,18 @@
 #define   ILK_PABSTRETCH_DIS 	(1<<21)
 
 
+/* 
+ * Framebuffer compression for Sandybridge
+ *
+ * The following two registers are of type GTTMMADR
+ */
+#define SNB_DPFC_CTL_SA		0x100100
+#define   SNB_CPU_FENCE_ENABLE	(1<<29)
+#define DPFC_CPU_FENCE_OFFSET	0x100104
+
+
+
+
 /*
  * GPIO regs
  */
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 59a6d89..9887172 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1264,6 +1264,12 @@ static void ironlake_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
 	/* enable it... */
 	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
 
+	if (IS_GEN6(dev)) {
+		I915_WRITE(SNB_DPFC_CTL_SA, 
+				SNB_CPU_FENCE_ENABLE | dev_priv->cfb_fence);
+		I915_WRITE(DPFC_CPU_FENCE_OFFSET, crtc->y);
+	}
+
 	DRM_DEBUG_KMS("enabled fbc on plane %d\n", intel_crtc->plane);
 }
 
@@ -6426,7 +6432,7 @@ static void intel_init_display(struct drm_device *dev)
 		dev_priv->display.dpms = i9xx_crtc_dpms;
 
 	if (I915_HAS_FBC(dev)) {
-		if (IS_IRONLAKE_M(dev)) {
+		if (HAS_PCH_SPLIT(dev)) {
 			dev_priv->display.fbc_enabled = ironlake_fbc_enabled;
 			dev_priv->display.enable_fbc = ironlake_enable_fbc;
 			dev_priv->display.disable_fbc = ironlake_disable_fbc;
-- 
1.7.2.3