drm/i915: framebuffer compression for GM45+

Add support for framebuffer compression on GM45 and above.  Removes
some unnecessary I915_HAS_FBC checks as well (this is now part of the
FBC display function).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>

drivers/gpu/drm/i915/i915_dma.c

@@ -1119,34 +1119,47 @@ static void i915_setup_compression(struct drm_device *dev, int size)
 		return;
 	}
 
-	compressed_llb = drm_mm_search_free(&dev_priv->vram, 4096, 4096, 0);
-	if (!compressed_llb) {
-		i915_warn_stolen(dev);
-		return;
+	cfb_base = i915_gtt_to_phys(dev, compressed_fb->start);
+	if (!cfb_base) {
+		DRM_ERROR("failed to get stolen phys addr, disabling FBC\n");
+		drm_mm_put_block(compressed_fb);
 	}
 
-	compressed_llb = drm_mm_get_block(compressed_llb, 4096, 4096);
-	if (!compressed_llb) {
-		i915_warn_stolen(dev);
-		return;
+	if (!IS_GM45(dev)) {
+		compressed_llb = drm_mm_search_free(&dev_priv->vram, 4096,
+						    4096, 0);
+		if (!compressed_llb) {
+			i915_warn_stolen(dev);
+			return;
+		}
+
+		compressed_llb = drm_mm_get_block(compressed_llb, 4096, 4096);
+		if (!compressed_llb) {
+			i915_warn_stolen(dev);
+			return;
+		}
+
+		ll_base = i915_gtt_to_phys(dev, compressed_llb->start);
+		if (!ll_base) {
+			DRM_ERROR("failed to get stolen phys addr, disabling FBC\n");
+			drm_mm_put_block(compressed_fb);
+			drm_mm_put_block(compressed_llb);
+		}
 	}
 
 	dev_priv->cfb_size = size;
 
-	cfb_base = i915_gtt_to_phys(dev, compressed_fb->start);
-	ll_base = i915_gtt_to_phys(dev, compressed_llb->start);
-	if (!cfb_base || !ll_base) {
-		DRM_ERROR("failed to get stolen phys addr, disabling FBC\n");
-		drm_mm_put_block(compressed_fb);
-		drm_mm_put_block(compressed_llb);
+	if (IS_GM45(dev)) {
+		g4x_disable_fbc(dev);
+		I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
+	} else {
+		i8xx_disable_fbc(dev);
+		I915_WRITE(FBC_CFB_BASE, cfb_base);
+		I915_WRITE(FBC_LL_BASE, ll_base);
 	}
 
-	i8xx_disable_fbc(dev);
-
 	DRM_DEBUG("FBC base 0x%08lx, ll base 0x%08lx, size %dM\n", cfb_base,
 		  ll_base, size >> 20);
-	I915_WRITE(FBC_CFB_BASE, cfb_base);
-	I915_WRITE(FBC_LL_BASE, ll_base);
 }
 
 static int i915_load_modeset_init(struct drm_device *dev,
@@ -1194,7 +1207,7 @@ static int i915_load_modeset_init(struct drm_device *dev,
 		goto out;
 
 	/* Try to set up FBC with a reasonable compressed buffer size */
-	if (IS_MOBILE(dev) && (IS_I9XX(dev) || IS_I965G(dev)) &&
+	if (IS_MOBILE(dev) && (IS_I9XX(dev) || IS_I965G(dev) || IS_GM45(dev)) &&
 	    i915_powersave) {
 		int cfb_size;
 

drivers/gpu/drm/i915/i915_drv.h

@@ -827,6 +827,7 @@ static inline void opregion_enable_asle(struct drm_device *dev) { return; }
 extern void intel_modeset_init(struct drm_device *dev);
 extern void intel_modeset_cleanup(struct drm_device *dev);
 extern void i8xx_disable_fbc(struct drm_device *dev);
+extern void g4x_disable_fbc(struct drm_device *dev);
 
 /**
  * Lock test for when it's just for synchronization of ring access.

drivers/gpu/drm/i915/i915_reg.h

@@ -351,6 +351,33 @@
 
 #define FBC_LL_SIZE		(1536)
 
+/* Framebuffer compression for GM45+ */
+#define DPFC_CB_BASE		0x3200
+#define DPFC_CONTROL		0x3208
+#define   DPFC_CTL_EN		(1<<31)
+#define   DPFC_CTL_PLANEA	(0<<30)
+#define   DPFC_CTL_PLANEB	(1<<30)
+#define   DPFC_CTL_FENCE_EN	(1<<29)
+#define   DPFC_SR_EN		(1<<10)
+#define   DPFC_CTL_LIMIT_1X	(0<<6)
+#define   DPFC_CTL_LIMIT_2X	(1<<6)
+#define   DPFC_CTL_LIMIT_4X	(2<<6)
+#define DPFC_RECOMP_CTL		0x320c
+#define   DPFC_RECOMP_STALL_EN	(1<<27)
+#define   DPFC_RECOMP_STALL_WM_SHIFT (16)
+#define   DPFC_RECOMP_STALL_WM_MASK (0x07ff0000)
+#define   DPFC_RECOMP_TIMER_COUNT_SHIFT (0)
+#define   DPFC_RECOMP_TIMER_COUNT_MASK (0x0000003f)
+#define DPFC_STATUS		0x3210
+#define   DPFC_INVAL_SEG_SHIFT  (16)
+#define   DPFC_INVAL_SEG_MASK	(0x07ff0000)
+#define   DPFC_COMP_SEG_SHIFT	(0)
+#define   DPFC_COMP_SEG_MASK	(0x000003ff)
+#define DPFC_STATUS2		0x3214
+#define DPFC_FENCE_YOFF		0x3218
+#define DPFC_CHICKEN		0x3224
+#define   DPFC_HT_MODIFY	(1<<31)
+
 /*
  * GPIO regs
  */

drivers/gpu/drm/i915/intel_display.c

@@ -1030,6 +1030,65 @@ static bool i8xx_fbc_enabled(struct drm_crtc *crtc)
 	return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
 }
 
+static void g4x_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_framebuffer *fb = crtc->fb;
+	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
+	struct drm_i915_gem_object *obj_priv = intel_fb->obj->driver_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+	int plane = (intel_crtc->plane == 0 ? DPFC_CTL_PLANEA :
+		     DPFC_CTL_PLANEB);
+	unsigned long stall_watermark = 200;
+	u32 dpfc_ctl;
+
+	dev_priv->cfb_pitch = (dev_priv->cfb_pitch / 64) - 1;
+	dev_priv->cfb_fence = obj_priv->fence_reg;
+	dev_priv->cfb_plane = intel_crtc->plane;
+
+	dpfc_ctl = plane | DPFC_SR_EN | DPFC_CTL_LIMIT_1X;
+	if (obj_priv->tiling_mode != I915_TILING_NONE) {
+		dpfc_ctl |= DPFC_CTL_FENCE_EN | dev_priv->cfb_fence;
+		I915_WRITE(DPFC_CHICKEN, DPFC_HT_MODIFY);
+	} else {
+		I915_WRITE(DPFC_CHICKEN, ~DPFC_HT_MODIFY);
+	}
+
+	I915_WRITE(DPFC_CONTROL, dpfc_ctl);
+	I915_WRITE(DPFC_RECOMP_CTL, DPFC_RECOMP_STALL_EN |
+		   (stall_watermark << DPFC_RECOMP_STALL_WM_SHIFT) |
+		   (interval << DPFC_RECOMP_TIMER_COUNT_SHIFT));
+	I915_WRITE(DPFC_FENCE_YOFF, crtc->y);
+
+	/* enable it... */
+	I915_WRITE(DPFC_CONTROL, I915_READ(DPFC_CONTROL) | DPFC_CTL_EN);
+
+	DRM_DEBUG("enabled fbc on plane %d\n", intel_crtc->plane);
+}
+
+void g4x_disable_fbc(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	u32 dpfc_ctl;
+
+	/* Disable compression */
+	dpfc_ctl = I915_READ(DPFC_CONTROL);
+	dpfc_ctl &= ~DPFC_CTL_EN;
+	I915_WRITE(DPFC_CONTROL, dpfc_ctl);
+	intel_wait_for_vblank(dev);
+
+	DRM_DEBUG("disabled FBC\n");
+}
+
+static bool g4x_fbc_enabled(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
+}
+
 /**
  * intel_update_fbc - enable/disable FBC as needed
  * @crtc: CRTC to point the compressor at
@@ -1097,7 +1156,7 @@ static void intel_update_fbc(struct drm_crtc *crtc,
 		DRM_DEBUG("mode too large for compression, disabling\n");
 		goto out_disable;
 	}
-	if (IS_I9XX(dev) && plane != 0) {
+	if ((IS_I915GM(dev) || IS_I945GM(dev)) && plane != 0) {
 		DRM_DEBUG("plane not 0, disabling compression\n");
 		goto out_disable;
 	}
@@ -1265,7 +1324,7 @@ intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
 		I915_READ(dspbase);
 	}
 
-	if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+	if ((IS_I965G(dev) || plane == 0))
 		intel_update_fbc(crtc, &crtc->mode);
 
 	intel_wait_for_vblank(dev);
@@ -1774,7 +1833,8 @@ static void i9xx_crtc_dpms(struct drm_crtc *crtc, int mode)
 
 		intel_crtc_load_lut(crtc);
 
-		intel_update_fbc(crtc, &crtc->mode);
+		if ((IS_I965G(dev) || plane == 0))
+			intel_update_fbc(crtc, &crtc->mode);
 
 		/* Give the overlay scaler a chance to enable if it's on this pipe */
 		//intel_crtc_dpms_video(crtc, true); TODO
@@ -2988,7 +3048,8 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 	/* Flush the plane changes */
 	ret = intel_pipe_set_base(crtc, x, y, old_fb);
 
-	intel_update_fbc(crtc, &crtc->mode);
+	if ((IS_I965G(dev) || plane == 0))
+		intel_update_fbc(crtc, &crtc->mode);
 
 	intel_update_watermarks(dev);
 
@@ -3121,7 +3182,7 @@ static int intel_crtc_cursor_set(struct drm_crtc *crtc,
 		drm_gem_object_unreference(intel_crtc->cursor_bo);
 	}
 
-	if (I915_HAS_FBC(dev) && (IS_I965G(dev) || plane == 0))
+	if ((IS_I965G(dev) || plane == 0))
 		intel_update_fbc(crtc, &crtc->mode);
 
 	mutex_unlock(&dev->struct_mutex);
@@ -4108,12 +4169,16 @@ static void intel_init_display(struct drm_device *dev)
 
 	/* Only mobile has FBC, leave pointers NULL for other chips */
 	if (IS_MOBILE(dev)) {
-		/* 855GM needs testing */
-		if (IS_I965GM(dev) || IS_I945GM(dev) || IS_I915GM(dev)) {
+		if (IS_GM45(dev)) {
+			dev_priv->display.fbc_enabled = g4x_fbc_enabled;
+			dev_priv->display.enable_fbc = g4x_enable_fbc;
+			dev_priv->display.disable_fbc = g4x_disable_fbc;
+		} else if (IS_I965GM(dev) || IS_I945GM(dev) || IS_I915GM(dev)) {
 			dev_priv->display.fbc_enabled = i8xx_fbc_enabled;
 			dev_priv->display.enable_fbc = i8xx_enable_fbc;
 			dev_priv->display.disable_fbc = i8xx_disable_fbc;
 		}
+		/* 855GM needs testing */
 	}
 
 	/* Returns the core display clock speed */