drm/i915: implement drmmode overlay support v4

This implements intel overlay support for kms via a device-specific
ioctl. Thomas Hellstrom brought up the idea of a general ioctl (on
dri-devel). We've reached the conclusion that such an infrastructure
only makes sense when multiple kms overlay implementations exists,
which atm don't (and it doesn't look like this is gonna change).

Open issues:
- Runs in sync with the gpu, i.e. unnecessary waiting. I've decided
  to wait on this because the hw tends to hang when changing something
  in this area. I left some dummy functions as infrastructure.
- polyphase filtering uses a static table.
- uses uninterruptible sleeps. Unfortunately the alternatives may
  unnecessarily wedged the hw if/when we timeout too early (and
  userspace only overloaded the batch buffers with stuff worth a few
  secs of gpu time).

Changes since v1:
- fix off-by-one misconception on my side. This fixes fullscreen
  playback.
Changes since v2:
- add underrun detection as spec'ed for i965.
- flush caches properly, fixing visual corruptions.
Changes since v4:
- fix up cache flushing of overlay memory regs.
- killed require_pipe_a logic - it hangs the chip.

Tested-By: diego.abelenda@gmail.com (on a 865G)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
[anholt: Resolved against the MADVISE ioctl going in before this one]
Signed-off-by: NEric Anholt <eric@anholt.net>

drivers/gpu/drm/i915/Makefile

@@ -23,6 +23,7 @@ i915-y := i915_drv.o i915_dma.o i915_irq.o i915_mem.o \
 	  intel_fb.o \
 	  intel_tv.o \
 	  intel_dvo.o \
+	  intel_overlay.o \
 	  dvo_ch7xxx.o \
 	  dvo_ch7017.o \
 	  dvo_ivch.o \

drivers/gpu/drm/i915/i915_dma.c

@@ -807,6 +807,9 @@ static int i915_getparam(struct drm_device *dev, void *data,
 	case I915_PARAM_NUM_FENCES_AVAIL:
 		value = dev_priv->num_fence_regs - dev_priv->fence_reg_start;
 		break;
+	case I915_PARAM_HAS_OVERLAY:
+		value = dev_priv->overlay ? 1 : 0;
+		break;
 	default:
 		DRM_DEBUG_DRIVER("Unknown parameter %d\n",
 					param->param);
@@ -1548,6 +1551,8 @@ int i915_driver_unload(struct drm_device *dev)
 		mutex_unlock(&dev->struct_mutex);
 		drm_mm_takedown(&dev_priv->vram);
 		i915_gem_lastclose(dev);
+
+		intel_cleanup_overlay(dev);
 	}
 
 	pci_dev_put(dev_priv->bridge_dev);
@@ -1656,6 +1661,8 @@ struct drm_ioctl_desc i915_ioctls[] = {
 	DRM_IOCTL_DEF(DRM_I915_GEM_GET_APERTURE, i915_gem_get_aperture_ioctl, 0),
 	DRM_IOCTL_DEF(DRM_I915_GET_PIPE_FROM_CRTC_ID, intel_get_pipe_from_crtc_id, 0),
 	DRM_IOCTL_DEF(DRM_I915_GEM_MADVISE, i915_gem_madvise_ioctl, 0),
+	DRM_IOCTL_DEF(DRM_I915_OVERLAY_PUT_IMAGE, intel_overlay_put_image, DRM_MASTER|DRM_CONTROL_ALLOW),
+	DRM_IOCTL_DEF(DRM_I915_OVERLAY_ATTRS, intel_overlay_attrs, DRM_MASTER|DRM_CONTROL_ALLOW),
 };
 
 int i915_max_ioctl = DRM_ARRAY_SIZE(i915_ioctls);

drivers/gpu/drm/i915/i915_drv.h

@@ -170,6 +170,8 @@ struct drm_i915_display_funcs {
 	/* clock gating init */
 };
 
+struct intel_overlay;
+
 typedef struct drm_i915_private {
 	struct drm_device *dev;
 
@@ -241,6 +243,9 @@ typedef struct drm_i915_private {
 
 	struct intel_opregion opregion;
 
+	/* overlay */
+	struct intel_overlay *overlay;
+
 	/* LVDS info */
 	int backlight_duty_cycle;  /* restore backlight to this value */
 	bool panel_wants_dither;

drivers/gpu/drm/i915/i915_reg.h

@@ -140,6 +140,7 @@
 #define MI_NOOP			MI_INSTR(0, 0)
 #define MI_USER_INTERRUPT	MI_INSTR(0x02, 0)
 #define MI_WAIT_FOR_EVENT       MI_INSTR(0x03, 0)
+#define   MI_WAIT_FOR_OVERLAY_FLIP	(1<<16)
 #define   MI_WAIT_FOR_PLANE_B_FLIP      (1<<6)
 #define   MI_WAIT_FOR_PLANE_A_FLIP      (1<<2)
 #define   MI_WAIT_FOR_PLANE_A_SCANLINES (1<<1)
@@ -151,6 +152,10 @@
 #define   MI_END_SCENE		(1 << 4) /* flush binner and incr scene count */
 #define MI_BATCH_BUFFER_END	MI_INSTR(0x0a, 0)
 #define MI_REPORT_HEAD		MI_INSTR(0x07, 0)
+#define MI_OVERLAY_FLIP		MI_INSTR(0x11,0)
+#define   MI_OVERLAY_CONTINUE	(0x0<<21)
+#define   MI_OVERLAY_ON		(0x1<<21)
+#define   MI_OVERLAY_OFF	(0x2<<21)
 #define MI_LOAD_SCAN_LINES_INCL MI_INSTR(0x12, 0)
 #define MI_STORE_DWORD_IMM	MI_INSTR(0x20, 1)
 #define   MI_MEM_VIRTUAL	(1 << 22) /* 965+ only */

drivers/gpu/drm/i915/intel_display.c

@@ -1781,6 +1781,22 @@ static void igdng_crtc_dpms(struct drm_crtc *crtc, int mode)
 	}
 }
 
+static void intel_crtc_dpms_overlay(struct intel_crtc *intel_crtc, bool enable)
+{
+	struct intel_overlay *overlay;
+
+	if (!enable && intel_crtc->overlay) {
+		overlay = intel_crtc->overlay;
+		mutex_lock(&overlay->dev->struct_mutex);
+		intel_overlay_switch_off(overlay);
+		mutex_unlock(&overlay->dev->struct_mutex);
+	}
+	/* Let userspace switch the overlay on again. In most cases userspace
+	 * has to recompute where to put it anyway. */
+
+	return;
+}
+
 static void i9xx_crtc_dpms(struct drm_crtc *crtc, int mode)
 {
 	struct drm_device *dev = crtc->dev;
@@ -1839,12 +1855,13 @@ static void i9xx_crtc_dpms(struct drm_crtc *crtc, int mode)
 			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
+		intel_crtc_dpms_overlay(intel_crtc, true);
 	break;
 	case DRM_MODE_DPMS_OFF:
 		intel_update_watermarks(dev);
+
 		/* Give the overlay scaler a chance to disable if it's on this pipe */
-		//intel_crtc_dpms_video(crtc, FALSE); TODO
+		intel_crtc_dpms_overlay(intel_crtc, false);
 
 		if (dev_priv->cfb_plane == plane &&
 		    dev_priv->display.disable_fbc)
@@ -2039,7 +2056,7 @@ static int i830_get_display_clock_speed(struct drm_device *dev)
  * Return the pipe currently connected to the panel fitter,
  * or -1 if the panel fitter is not present or not in use
  */
-static int intel_panel_fitter_pipe (struct drm_device *dev)
+int intel_panel_fitter_pipe (struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32  pfit_control;
@@ -4458,6 +4475,8 @@ void intel_modeset_init(struct drm_device *dev)
 	INIT_WORK(&dev_priv->idle_work, intel_idle_update);
 	setup_timer(&dev_priv->idle_timer, intel_gpu_idle_timer,
 		    (unsigned long)dev);
+
+	intel_setup_overlay(dev);
 }
 
 void intel_modeset_cleanup(struct drm_device *dev)

drivers/gpu/drm/i915/intel_drv.h

@@ -110,6 +110,25 @@ struct intel_output {
 	int clone_mask;
 };
 
+struct intel_crtc;
+struct intel_overlay {
+	struct drm_device *dev;
+	struct intel_crtc *crtc;
+	struct drm_i915_gem_object *vid_bo;
+	struct drm_i915_gem_object *old_vid_bo;
+	int active;
+	int pfit_active;
+	u32 pfit_vscale_ratio; /* shifted-point number, (1<<12) == 1.0 */
+	u32 color_key;
+	u32 brightness, contrast, saturation;
+	u32 old_xscale, old_yscale;
+	/* register access */
+	u32 flip_addr;
+	struct drm_i915_gem_object *reg_bo;
+	void *virt_addr;
+	int hw_wedged;
+};
+
 struct intel_crtc {
 	struct drm_crtc base;
 	enum pipe pipe;
@@ -121,6 +140,7 @@ struct intel_crtc {
 	bool busy; /* is scanout buffer being updated frequently? */
 	struct timer_list idle_timer;
 	bool lowfreq_avail;
+	struct intel_overlay *overlay;
 };
 
 #define to_intel_crtc(x) container_of(x, struct intel_crtc, base)
@@ -148,6 +168,7 @@ intel_dp_set_m_n(struct drm_crtc *crtc, struct drm_display_mode *mode,
 extern void intel_edp_link_config (struct intel_output *, int *, int *);
 
 
+extern int intel_panel_fitter_pipe (struct drm_device *dev);
 extern void intel_crtc_load_lut(struct drm_crtc *crtc);
 extern void intel_encoder_prepare (struct drm_encoder *encoder);
 extern void intel_encoder_commit (struct drm_encoder *encoder);
@@ -183,4 +204,11 @@ extern int intel_framebuffer_create(struct drm_device *dev,
 				    struct drm_framebuffer **fb,
 				    struct drm_gem_object *obj);
 
+extern void intel_setup_overlay(struct drm_device *dev);
+extern void intel_cleanup_overlay(struct drm_device *dev);
+extern int intel_overlay_switch_off(struct intel_overlay *overlay);
+extern int intel_overlay_put_image(struct drm_device *dev, void *data,
+				   struct drm_file *file_priv);
+extern int intel_overlay_attrs(struct drm_device *dev, void *data,
+			       struct drm_file *file_priv);
 #endif /* __INTEL_DRV_H__ */

drivers/gpu/drm/i915/intel_overlay.c

+/*
+ * Copyright © 2009
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ *    Daniel Vetter <daniel@ffwll.ch>
+ *
+ * Derived from Xorg ddx, xf86-video-intel, src/i830_video.c
+ */
+#include "drmP.h"
+#include "drm.h"
+#include "i915_drm.h"
+#include "i915_drv.h"
+#include "i915_reg.h"
+#include "intel_drv.h"
+
+/* Limits for overlay size. According to intel doc, the real limits are:
+ * Y width: 4095, UV width (planar): 2047, Y height: 2047,
+ * UV width (planar): * 1023. But the xorg thinks 2048 for height and width. Use
+ * the mininum of both.  */
+#define IMAGE_MAX_WIDTH		2048
+#define IMAGE_MAX_HEIGHT	2046 /* 2 * 1023 */
+/* on 830 and 845 these large limits result in the card hanging */
+#define IMAGE_MAX_WIDTH_LEGACY	1024
+#define IMAGE_MAX_HEIGHT_LEGACY	1088
+
+/* overlay register definitions */
+/* OCMD register */
+#define OCMD_TILED_SURFACE	(0x1<<19)
+#define OCMD_MIRROR_MASK	(0x3<<17)
+#define OCMD_MIRROR_MODE	(0x3<<17)
+#define OCMD_MIRROR_HORIZONTAL	(0x1<<17)
+#define OCMD_MIRROR_VERTICAL	(0x2<<17)
+#define OCMD_MIRROR_BOTH	(0x3<<17)
+#define OCMD_BYTEORDER_MASK	(0x3<<14) /* zero for YUYV or FOURCC YUY2 */
+#define OCMD_UV_SWAP		(0x1<<14) /* YVYU */
+#define OCMD_Y_SWAP		(0x2<<14) /* UYVY or FOURCC UYVY */
+#define OCMD_Y_AND_UV_SWAP	(0x3<<14) /* VYUY */
+#define OCMD_SOURCE_FORMAT_MASK (0xf<<10)
+#define OCMD_RGB_888		(0x1<<10) /* not in i965 Intel docs */
+#define OCMD_RGB_555		(0x2<<10) /* not in i965 Intel docs */
+#define OCMD_RGB_565		(0x3<<10) /* not in i965 Intel docs */
+#define OCMD_YUV_422_PACKED	(0x8<<10)
+#define OCMD_YUV_411_PACKED	(0x9<<10) /* not in i965 Intel docs */
+#define OCMD_YUV_420_PLANAR	(0xc<<10)
+#define OCMD_YUV_422_PLANAR	(0xd<<10)
+#define OCMD_YUV_410_PLANAR	(0xe<<10) /* also 411 */
+#define OCMD_TVSYNCFLIP_PARITY	(0x1<<9)
+#define OCMD_TVSYNCFLIP_ENABLE	(0x1<<7)
+#define OCMD_BUF_TYPE_MASK	(Ox1<<5)
+#define OCMD_BUF_TYPE_FRAME	(0x0<<5)
+#define OCMD_BUF_TYPE_FIELD	(0x1<<5)
+#define OCMD_TEST_MODE		(0x1<<4)
+#define OCMD_BUFFER_SELECT	(0x3<<2)
+#define OCMD_BUFFER0		(0x0<<2)
+#define OCMD_BUFFER1		(0x1<<2)
+#define OCMD_FIELD_SELECT	(0x1<<2)
+#define OCMD_FIELD0		(0x0<<1)
+#define OCMD_FIELD1		(0x1<<1)
+#define OCMD_ENABLE		(0x1<<0)
+
+/* OCONFIG register */
+#define OCONF_PIPE_MASK		(0x1<<18)
+#define OCONF_PIPE_A		(0x0<<18)
+#define OCONF_PIPE_B		(0x1<<18)
+#define OCONF_GAMMA2_ENABLE	(0x1<<16)
+#define OCONF_CSC_MODE_BT601	(0x0<<5)
+#define OCONF_CSC_MODE_BT709	(0x1<<5)
+#define OCONF_CSC_BYPASS	(0x1<<4)
+#define OCONF_CC_OUT_8BIT	(0x1<<3)
+#define OCONF_TEST_MODE		(0x1<<2)
+#define OCONF_THREE_LINE_BUFFER	(0x1<<0)
+#define OCONF_TWO_LINE_BUFFER	(0x0<<0)
+
+/* DCLRKM (dst-key) register */
+#define DST_KEY_ENABLE		(0x1<<31)
+#define CLK_RGB24_MASK		0x0
+#define CLK_RGB16_MASK		0x070307
+#define CLK_RGB15_MASK		0x070707
+#define CLK_RGB8I_MASK		0xffffff
+
+#define RGB16_TO_COLORKEY(c) \
+	(((c & 0xF800) << 8) | ((c & 0x07E0) << 5) | ((c & 0x001F) << 3))
+#define RGB15_TO_COLORKEY(c) \
+	(((c & 0x7c00) << 9) | ((c & 0x03E0) << 6) | ((c & 0x001F) << 3))
+
+/* overlay flip addr flag */
+#define OFC_UPDATE		0x1
+
+/* polyphase filter coefficients */
+#define N_HORIZ_Y_TAPS          5
+#define N_VERT_Y_TAPS           3
+#define N_HORIZ_UV_TAPS         3
+#define N_VERT_UV_TAPS          3
+#define N_PHASES                17
+#define MAX_TAPS                5
+
+/* memory bufferd overlay registers */
+struct overlay_registers {
+    u32 OBUF_0Y;
+    u32 OBUF_1Y;
+    u32 OBUF_0U;
+    u32 OBUF_0V;
+    u32 OBUF_1U;
+    u32 OBUF_1V;
+    u32 OSTRIDE;
+    u32 YRGB_VPH;
+    u32 UV_VPH;
+    u32 HORZ_PH;
+    u32 INIT_PHS;
+    u32 DWINPOS;
+    u32 DWINSZ;
+    u32 SWIDTH;
+    u32 SWIDTHSW;
+    u32 SHEIGHT;
+    u32 YRGBSCALE;
+    u32 UVSCALE;
+    u32 OCLRC0;
+    u32 OCLRC1;
+    u32 DCLRKV;
+    u32 DCLRKM;
+    u32 SCLRKVH;
+    u32 SCLRKVL;
+    u32 SCLRKEN;
+    u32 OCONFIG;
+    u32 OCMD;
+    u32 RESERVED1; /* 0x6C */
+    u32 OSTART_0Y;
+    u32 OSTART_1Y;
+    u32 OSTART_0U;
+    u32 OSTART_0V;
+    u32 OSTART_1U;
+    u32 OSTART_1V;
+    u32 OTILEOFF_0Y;
+    u32 OTILEOFF_1Y;
+    u32 OTILEOFF_0U;
+    u32 OTILEOFF_0V;
+    u32 OTILEOFF_1U;
+    u32 OTILEOFF_1V;
+    u32 FASTHSCALE; /* 0xA0 */
+    u32 UVSCALEV; /* 0xA4 */
+    u32 RESERVEDC[(0x200 - 0xA8) / 4]; /* 0xA8 - 0x1FC */
+    u16 Y_VCOEFS[N_VERT_Y_TAPS * N_PHASES]; /* 0x200 */
+    u16 RESERVEDD[0x100 / 2 - N_VERT_Y_TAPS * N_PHASES];
+    u16 Y_HCOEFS[N_HORIZ_Y_TAPS * N_PHASES]; /* 0x300 */
+    u16 RESERVEDE[0x200 / 2 - N_HORIZ_Y_TAPS * N_PHASES];
+    u16 UV_VCOEFS[N_VERT_UV_TAPS * N_PHASES]; /* 0x500 */
+    u16 RESERVEDF[0x100 / 2 - N_VERT_UV_TAPS * N_PHASES];
+    u16 UV_HCOEFS[N_HORIZ_UV_TAPS * N_PHASES]; /* 0x600 */
+    u16 RESERVEDG[0x100 / 2 - N_HORIZ_UV_TAPS * N_PHASES];
+};
+
+/* overlay flip addr flag */
+#define OFC_UPDATE		0x1
+
+#define OVERLAY_NONPHYSICAL(dev) (IS_G33(dev) || IS_I965G(dev))
+#define OVERLAY_EXISTS(dev) (!IS_G4X(dev) && !IS_IGDNG(dev))
+
+
+static struct overlay_registers *intel_overlay_map_regs_atomic(struct intel_overlay *overlay)
+{
+        drm_i915_private_t *dev_priv = overlay->dev->dev_private;
+	struct overlay_registers *regs;
+
+	/* no recursive mappings */
+	BUG_ON(overlay->virt_addr);
+
+	if (OVERLAY_NONPHYSICAL(overlay->dev)) {
+		regs = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
+				overlay->reg_bo->gtt_offset);
+
+		if (!regs) {
+			DRM_ERROR("failed to map overlay regs in GTT\n");
+			return NULL;
+		}
+	} else
+		regs = overlay->reg_bo->phys_obj->handle->vaddr;
+
+	return overlay->virt_addr = regs;
+}
+
+static void intel_overlay_unmap_regs_atomic(struct intel_overlay *overlay)
+{
+	struct drm_device *dev = overlay->dev;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+
+	if (OVERLAY_NONPHYSICAL(overlay->dev))
+		io_mapping_unmap_atomic(overlay->virt_addr);
+
+	overlay->virt_addr = NULL;
+
+	I915_READ(OVADD); /* flush wc cashes */
+
+	return;
+}
+
+/* overlay needs to be disable in OCMD reg */
+static int intel_overlay_on(struct intel_overlay *overlay)
+{
+	struct drm_device *dev = overlay->dev;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	int ret;
+	RING_LOCALS;
+
+	BUG_ON(overlay->active);
+
+	BEGIN_LP_RING(6);
+	OUT_RING(MI_FLUSH);
+	OUT_RING(MI_NOOP);
+	OUT_RING(MI_OVERLAY_FLIP | MI_OVERLAY_ON);
+	OUT_RING(overlay->flip_addr | OFC_UPDATE);
+	OUT_RING(MI_WAIT_FOR_EVENT | MI_WAIT_FOR_OVERLAY_FLIP);
+	OUT_RING(MI_NOOP);
+	ADVANCE_LP_RING();
+
+	ret = i915_lp_ring_sync(dev);
+	if (ret != 0) {
+		DRM_ERROR("intel overlay: ring sync failed, hw likely wedged\n");
+		overlay->hw_wedged = 1;
+		return 0;
+	}
+
+	overlay->active = 1;
+
+	return 0;
+}
+
+/* overlay needs to be enabled in OCMD reg */
+static void intel_overlay_continue(struct intel_overlay *overlay,
+			    bool load_polyphase_filter)
+{
+	struct drm_device *dev = overlay->dev;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	u32 flip_addr = overlay->flip_addr;
+	u32 tmp;
+	int ret;
+	RING_LOCALS;
+
+	BUG_ON(!overlay->active);
+
+	if (load_polyphase_filter)
+		flip_addr |= OFC_UPDATE;
+
+	/* check for underruns */
+	tmp = I915_READ(DOVSTA);
+	if (tmp & (1 << 17))
+		DRM_DEBUG("overlay underrun, DOVSTA: %x\n", tmp);
+
+	BEGIN_LP_RING(6);
+	OUT_RING(MI_FLUSH);
+	OUT_RING(MI_NOOP);
+	OUT_RING(MI_OVERLAY_FLIP | MI_OVERLAY_CONTINUE);
+	OUT_RING(flip_addr);
+        OUT_RING(MI_WAIT_FOR_EVENT | MI_WAIT_FOR_OVERLAY_FLIP);
+        OUT_RING(MI_NOOP);
+        ADVANCE_LP_RING();
+
+	/* run in lockstep with the hw for easier testing */
+	ret = i915_lp_ring_sync(dev);
+	if (ret != 0) {
+		DRM_ERROR("intel overlay: ring sync failed, hw likely wedged\n");
+		overlay->hw_wedged = 1;
+	}
+}
+
+static int intel_overlay_wait_flip(struct intel_overlay *overlay)
+{
+	/* don't overcomplicate things for now with asynchronous operations
+	 * see comment above */
+	return 0;
+}
+
+/* overlay needs to be disabled in OCMD reg */
+static int intel_overlay_off(struct intel_overlay *overlay)
+{
+	u32 flip_addr = overlay->flip_addr;
+	struct drm_device *dev = overlay->dev;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	int ret;
+	RING_LOCALS;
+
+	BUG_ON(!overlay->active);
+
+	/* According to intel docs the overlay hw may hang (when switching
+	 * off) without loading the filter coeffs. It is however unclear whether
+	 * this applies to the disabling of the overlay or to the switching off
+	 * of the hw. Do it in both cases */
+	flip_addr |= OFC_UPDATE;
+
+	/* wait for overlay to go idle */
+	BEGIN_LP_RING(6);
+	OUT_RING(MI_FLUSH);
+	OUT_RING(MI_NOOP);
+	OUT_RING(MI_OVERLAY_FLIP | MI_OVERLAY_CONTINUE);
+	OUT_RING(flip_addr);
+        OUT_RING(MI_WAIT_FOR_EVENT | MI_WAIT_FOR_OVERLAY_FLIP);
+        OUT_RING(MI_NOOP);
+        ADVANCE_LP_RING();
+
+	ret = i915_lp_ring_sync(dev);
+	if (ret != 0) {
+		DRM_ERROR("intel overlay: ring sync failed, hw likely wedged\n");
+		overlay->hw_wedged = 1;
+		return ret;
+	}
+
+	/* turn overlay off */
+	/* this is not done in userspace!
+	BEGIN_LP_RING(6);
+        OUT_RING(MI_FLUSH);
+        OUT_RING(MI_NOOP);
+        OUT_RING(MI_OVERLAY_FLIP | MI_OVERLAY_OFF);
+	OUT_RING(flip_addr);
+        OUT_RING(MI_WAIT_FOR_EVENT | MI_WAIT_FOR_OVERLAY_FLIP);
+        OUT_RING(MI_NOOP);
+	ADVANCE_LP_RING();
+
+	ret = i915_lp_ring_sync(dev);
+	if (ret != 0) {
+		DRM_ERROR("intel overlay: ring sync failed, hw likely wedged\n");
+		overlay->hw_wedged = 1;
+		return ret;
+	}*/
+
+	overlay->active = 0;
+
+	return ret;
+}
+
+/* wait for pending overlay flip and release old frame */
+static int intel_overlay_release_old_vid(struct intel_overlay *overlay)
+{
+	int ret;
+	struct drm_gem_object *obj;
+
+	ret = intel_overlay_wait_flip(overlay);
+	if (ret != 0)
+		return ret;
+
+	if (!overlay->old_vid_bo)
+		return 0;
+
+	obj = overlay->old_vid_bo->obj;
+	i915_gem_object_unpin(obj);
+	drm_gem_object_unreference(obj);
+	overlay->old_vid_bo = NULL;
+
+	return 0;
+}
+
+struct put_image_params {
+	int format;
+	short dst_x;
+	short dst_y;
+	short dst_w;
+	short dst_h;
+	short src_w;
+	short src_scan_h;
+	short src_scan_w;
+	short src_h;
+	short stride_Y;
+	short stride_UV;
+	int offset_Y;
+	int offset_U;
+	int offset_V;
+};
+
+static int packed_depth_bytes(u32 format)
+{
+	switch (format & I915_OVERLAY_DEPTH_MASK) {
+		case I915_OVERLAY_YUV422:
+			return 4;
+		case I915_OVERLAY_YUV411:
+			/* return 6; not implemented */
+		default:
+			return -EINVAL;
+	}
+}
+
+static int packed_width_bytes(u32 format, short width)
+{
+	switch (format & I915_OVERLAY_DEPTH_MASK) {
+		case I915_OVERLAY_YUV422:
+			return width << 1;
+		default:
+			return -EINVAL;
+	}
+}
+
+static int uv_hsubsampling(u32 format)
+{
+	switch (format & I915_OVERLAY_DEPTH_MASK) {
+		case I915_OVERLAY_YUV422:
+		case I915_OVERLAY_YUV420:
+			return 2;
+		case I915_OVERLAY_YUV411:
+		case I915_OVERLAY_YUV410:
+			return 4;
+		default:
+			return -EINVAL;
+	}
+}
+
+static int uv_vsubsampling(u32 format)
+{
+	switch (format & I915_OVERLAY_DEPTH_MASK) {
+		case I915_OVERLAY_YUV420:
+		case I915_OVERLAY_YUV410:
+			return 2;
+		case I915_OVERLAY_YUV422:
+		case I915_OVERLAY_YUV411:
+			return 1;
+		default:
+			return -EINVAL;
+	}
+}
+
+static u32 calc_swidthsw(struct drm_device *dev, u32 offset, u32 width)
+{
+	u32 mask, shift, ret;
+	if (IS_I9XX(dev)) {
+		mask = 0x3f;
+		shift = 6;
+	} else {
+		mask = 0x1f;
+		shift = 5;
+	}
+	ret = ((offset + width + mask) >> shift) - (offset >> shift);
+	if (IS_I9XX(dev))
+		ret <<= 1;
+	ret -=1;
+	return ret << 2;
+}
+
+static const u16 y_static_hcoeffs[N_HORIZ_Y_TAPS * N_PHASES] = {
+	0x3000, 0xb4a0, 0x1930, 0x1920, 0xb4a0,
+	0x3000, 0xb500, 0x19d0, 0x1880, 0xb440,
+	0x3000, 0xb540, 0x1a88, 0x2f80, 0xb3e0,
+	0x3000, 0xb580, 0x1b30, 0x2e20, 0xb380,
+	0x3000, 0xb5c0, 0x1bd8, 0x2cc0, 0xb320,
+	0x3020, 0xb5e0, 0x1c60, 0x2b80, 0xb2c0,
+	0x3020, 0xb5e0, 0x1cf8, 0x2a20, 0xb260,
+	0x3020, 0xb5e0, 0x1d80, 0x28e0, 0xb200,
+	0x3020, 0xb5c0, 0x1e08, 0x3f40, 0xb1c0,
+	0x3020, 0xb580, 0x1e78, 0x3ce0, 0xb160,
+	0x3040, 0xb520, 0x1ed8, 0x3aa0, 0xb120,
+	0x3040, 0xb4a0, 0x1f30, 0x3880, 0xb0e0,
+	0x3040, 0xb400, 0x1f78, 0x3680, 0xb0a0,
+	0x3020, 0xb340, 0x1fb8, 0x34a0, 0xb060,
+	0x3020, 0xb240, 0x1fe0, 0x32e0, 0xb040,
+	0x3020, 0xb140, 0x1ff8, 0x3160, 0xb020,
+	0xb000, 0x3000, 0x0800, 0x3000, 0xb000};
+static const u16 uv_static_hcoeffs[N_HORIZ_UV_TAPS * N_PHASES] = {
+	0x3000, 0x1800, 0x1800, 0xb000, 0x18d0, 0x2e60,
+	0xb000, 0x1990, 0x2ce0, 0xb020, 0x1a68, 0x2b40,
+	0xb040, 0x1b20, 0x29e0, 0xb060, 0x1bd8, 0x2880,
+	0xb080, 0x1c88, 0x3e60, 0xb0a0, 0x1d28, 0x3c00,
+	0xb0c0, 0x1db8, 0x39e0, 0xb0e0, 0x1e40, 0x37e0,
+	0xb100, 0x1eb8, 0x3620, 0xb100, 0x1f18, 0x34a0,
+	0xb100, 0x1f68, 0x3360, 0xb0e0, 0x1fa8, 0x3240,
+	0xb0c0, 0x1fe0, 0x3140, 0xb060, 0x1ff0, 0x30a0,
+	0x3000, 0x0800, 0x3000};
+
+static void update_polyphase_filter(struct overlay_registers *regs)
+{
+	memcpy(regs->Y_HCOEFS, y_static_hcoeffs, sizeof(y_static_hcoeffs));
+	memcpy(regs->UV_HCOEFS, uv_static_hcoeffs, sizeof(uv_static_hcoeffs));
+}
+
+static bool update_scaling_factors(struct intel_overlay *overlay,
+				   struct overlay_registers *regs,
+				   struct put_image_params *params)
+{
+	/* fixed point with a 12 bit shift */
+	u32 xscale, yscale, xscale_UV, yscale_UV;
+#define FP_SHIFT 12
+#define FRACT_MASK 0xfff
+	bool scale_changed = false;
+	int uv_hscale = uv_hsubsampling(params->format);
+	int uv_vscale = uv_vsubsampling(params->format);
+
+	if (params->dst_w > 1)
+		xscale = ((params->src_scan_w - 1) << FP_SHIFT)
+			/(params->dst_w);
+	else
+		xscale = 1 << FP_SHIFT;
+
+	if (params->dst_h > 1)
+		yscale = ((params->src_scan_h - 1) << FP_SHIFT)
+			/(params->dst_h);
+	else
+		yscale = 1 << FP_SHIFT;
+
+	/*if (params->format & I915_OVERLAY_YUV_PLANAR) {*/
+		xscale_UV = xscale/uv_hscale;
+		yscale_UV = yscale/uv_vscale;
+		/* make the Y scale to UV scale ratio an exact multiply */
+		xscale = xscale_UV * uv_hscale;
+		yscale = yscale_UV * uv_vscale;
+	/*} else {
+		xscale_UV = 0;
+		yscale_UV = 0;
+	}*/
+
+	if (xscale != overlay->old_xscale || yscale != overlay->old_yscale)
+		scale_changed = true;
+	overlay->old_xscale = xscale;
+	overlay->old_yscale = yscale;
+
+	regs->YRGBSCALE = ((yscale & FRACT_MASK) << 20)
+		| ((xscale >> FP_SHIFT) << 16)
+		| ((xscale & FRACT_MASK) << 3);
+	regs->UVSCALE = ((yscale_UV & FRACT_MASK) << 20)
+		| ((xscale_UV >> FP_SHIFT) << 16)
+		| ((xscale_UV & FRACT_MASK) << 3);
+	regs->UVSCALEV = ((yscale >> FP_SHIFT) << 16)
+		| ((yscale_UV >> FP_SHIFT) << 0);
+
+	if (scale_changed)
+		update_polyphase_filter(regs);
+
+	return scale_changed;
+}
+
+static void update_colorkey(struct intel_overlay *overlay,
+			    struct overlay_registers *regs)
+{
+	u32 key = overlay->color_key;
+	switch (overlay->crtc->base.fb->bits_per_pixel) {
+		case 8:
+			regs->DCLRKV = 0;
+			regs->DCLRKM = CLK_RGB8I_MASK | DST_KEY_ENABLE;
+		case 16:
+			if (overlay->crtc->base.fb->depth == 15) {
+				regs->DCLRKV = RGB15_TO_COLORKEY(key);
+				regs->DCLRKM = CLK_RGB15_MASK | DST_KEY_ENABLE;
+			} else {
+				regs->DCLRKV = RGB16_TO_COLORKEY(key);
+				regs->DCLRKM = CLK_RGB16_MASK | DST_KEY_ENABLE;
+			}
+		case 24:
+		case 32:
+			regs->DCLRKV = key;
+			regs->DCLRKM = CLK_RGB24_MASK | DST_KEY_ENABLE;
+	}
+}
+
+static u32 overlay_cmd_reg(struct put_image_params *params)
+{
+	u32 cmd = OCMD_ENABLE | OCMD_BUF_TYPE_FRAME | OCMD_BUFFER0;
+
+	if (params->format & I915_OVERLAY_YUV_PLANAR) {
+		switch (params->format & I915_OVERLAY_DEPTH_MASK) {
+			case I915_OVERLAY_YUV422:
+				cmd |= OCMD_YUV_422_PLANAR;
+				break;
+			case I915_OVERLAY_YUV420:
+				cmd |= OCMD_YUV_420_PLANAR;
+				break;
+			case I915_OVERLAY_YUV411:
+			case I915_OVERLAY_YUV410:
+				cmd |= OCMD_YUV_410_PLANAR;
+				break;
+		}
+	} else { /* YUV packed */
+		switch (params->format & I915_OVERLAY_DEPTH_MASK) {
+			case I915_OVERLAY_YUV422:
+				cmd |= OCMD_YUV_422_PACKED;
+				break;
+			case I915_OVERLAY_YUV411:
+				cmd |= OCMD_YUV_411_PACKED;
+				break;
+		}
+
+		switch (params->format & I915_OVERLAY_SWAP_MASK) {
+			case I915_OVERLAY_NO_SWAP:
+				break;
+			case I915_OVERLAY_UV_SWAP:
+				cmd |= OCMD_UV_SWAP;
+				break;
+			case I915_OVERLAY_Y_SWAP:
+				cmd |= OCMD_Y_SWAP;
+				break;
+			case I915_OVERLAY_Y_AND_UV_SWAP:
+				cmd |= OCMD_Y_AND_UV_SWAP;
+				break;
+		}
+	}
+
+	return cmd;
+}
+
+int intel_overlay_do_put_image(struct intel_overlay *overlay,
+			       struct drm_gem_object *new_bo,
+			       struct put_image_params *params)
+{
+	int ret, tmp_width;
+	struct overlay_registers *regs;
+	bool scale_changed = false;
+	struct drm_i915_gem_object *bo_priv = new_bo->driver_private;
+	struct drm_device *dev = overlay->dev;
+
+	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
+	BUG_ON(!mutex_is_locked(&dev->mode_config.mutex));
+	BUG_ON(!overlay);
+
+	if (overlay->hw_wedged)
+		return -EBUSY;
+
+	ret = intel_overlay_release_old_vid(overlay);
+	if (ret != 0)
+		return ret;
+
+	ret = i915_gem_object_pin(new_bo, PAGE_SIZE);
+	if (ret != 0)
+		return ret;
+
+	ret = i915_gem_object_set_to_gtt_domain(new_bo, 0);
+	if (ret != 0)
+		goto out_unpin;
+
+	if (!overlay->active) {
+		regs = intel_overlay_map_regs_atomic(overlay);
+		if (!regs) {
+			ret = -ENOMEM;
+			goto out_unpin;
+		}
+		regs->OCONFIG = OCONF_CC_OUT_8BIT;
+		if (IS_I965GM(overlay->dev))
+			regs->OCONFIG |= OCONF_CSC_MODE_BT709;
+		regs->OCONFIG |= overlay->crtc->pipe == 0 ?
+			OCONF_PIPE_A : OCONF_PIPE_B;
+		intel_overlay_unmap_regs_atomic(overlay);
+
+		ret = intel_overlay_on(overlay);
+		if (ret != 0)
+			goto out_unpin;
+	}
+
+	regs = intel_overlay_map_regs_atomic(overlay);
+	if (!regs) {
+		ret = -ENOMEM;
+		goto out_unpin;
+	}
+
+	regs->DWINPOS = (params->dst_y << 16) | params->dst_x;
+	regs->DWINSZ = (params->dst_h << 16) | params->dst_w;
+
+	if (params->format & I915_OVERLAY_YUV_PACKED)
+		tmp_width = packed_width_bytes(params->format, params->src_w);
+	else
+		tmp_width = params->src_w;
+
+	regs->SWIDTH = params->src_w;
+	regs->SWIDTHSW = calc_swidthsw(overlay->dev,
+			params->offset_Y, tmp_width);
+	regs->SHEIGHT = params->src_h;
+	regs->OBUF_0Y = bo_priv->gtt_offset + params-> offset_Y;
+	regs->OSTRIDE = params->stride_Y;
+
+	if (params->format & I915_OVERLAY_YUV_PLANAR) {
+		int uv_hscale = uv_hsubsampling(params->format);
+		int uv_vscale = uv_vsubsampling(params->format);
+		u32 tmp_U, tmp_V;
+		regs->SWIDTH |= (params->src_w/uv_hscale) << 16;
+		tmp_U = calc_swidthsw(overlay->dev, params->offset_U,
+				params->src_w/uv_hscale);
+		tmp_V = calc_swidthsw(overlay->dev, params->offset_V,
+				params->src_w/uv_hscale);
+		regs->SWIDTHSW |= max_t(u32, tmp_U, tmp_V) << 16;
+		regs->SHEIGHT |= (params->src_h/uv_vscale) << 16;
+		regs->OBUF_0U = bo_priv->gtt_offset + params->offset_U;
+		regs->OBUF_0V = bo_priv->gtt_offset + params->offset_V;
+		regs->OSTRIDE |= params->stride_UV << 16;
+	}
+
+	scale_changed = update_scaling_factors(overlay, regs, params);
+
+	update_colorkey(overlay, regs);
+
+	regs->OCMD = overlay_cmd_reg(params);
+
+	intel_overlay_unmap_regs_atomic(overlay);
+
+	intel_overlay_continue(overlay, scale_changed);
+
+	overlay->old_vid_bo = overlay->vid_bo;
+	overlay->vid_bo = new_bo->driver_private;
+
+	return 0;
+
+out_unpin:
+	i915_gem_object_unpin(new_bo);
+	return ret;
+}
+
+int intel_overlay_switch_off(struct intel_overlay *overlay)
+{
+	int ret;
+	struct overlay_registers *regs;
+	struct drm_gem_object *obj;
+	struct drm_device *dev = overlay->dev;
+
+	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
+	BUG_ON(!mutex_is_locked(&dev->mode_config.mutex));
+
+	if (!overlay->active)
+		return 0;
+
+	if (overlay->hw_wedged)
+		return -EBUSY;
+
+	ret = intel_overlay_release_old_vid(overlay);
+	if (ret != 0)
+		return ret;
+
+	regs = intel_overlay_map_regs_atomic(overlay);
+	regs->OCMD = 0;
+	intel_overlay_unmap_regs_atomic(overlay);
+
+	ret = intel_overlay_off(overlay);
+	/* never have the overlay hw on without showing a frame */
+	BUG_ON(!overlay->vid_bo);
+	obj = overlay->vid_bo->obj;
+
+	i915_gem_object_unpin(obj);
+	drm_gem_object_unreference(obj);
+	overlay->vid_bo = NULL;
+
+	overlay->crtc->overlay = NULL;
+	overlay->crtc = NULL;
+
+	return 0;
+}
+
+static int check_overlay_possible_on_crtc(struct intel_overlay *overlay,
+					  struct intel_crtc *crtc)
+{
+        drm_i915_private_t *dev_priv = overlay->dev->dev_private;
+	u32 pipeconf;
+	int pipeconf_reg = (crtc->pipe == 0) ? PIPEACONF : PIPEBCONF;
+
+	if (!crtc->base.enabled || crtc->dpms_mode != DRM_MODE_DPMS_ON)
+		return -EINVAL;
+
+	pipeconf = I915_READ(pipeconf_reg);
+
+	/* can't use the overlay with double wide pipe */
+	if (!IS_I965G(overlay->dev) && pipeconf & PIPEACONF_DOUBLE_WIDE)
+		return -EINVAL;
+
+	return 0;
+}
+
+static void update_pfit_vscale_ratio(struct intel_overlay *overlay)
+{
+	struct drm_device *dev = overlay->dev;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	u32 ratio;
+	u32 pfit_control = I915_READ(PFIT_CONTROL);
+
+	/* XXX: This is not the same logic as in the xorg driver, but more in
+	 * line with the intel documentation for the i965 */
+	if (!IS_I965G(dev) && (pfit_control & VERT_AUTO_SCALE)) {
+		ratio = I915_READ(PFIT_AUTO_RATIOS) >> PFIT_VERT_SCALE_SHIFT;
+	} else { /* on i965 use the PGM reg to read out the autoscaler values */
+		ratio = I915_READ(PFIT_PGM_RATIOS);
+		if (IS_I965G(dev))
+			ratio >>= PFIT_VERT_SCALE_SHIFT_965;
+		else
+			ratio >>= PFIT_VERT_SCALE_SHIFT;
+	}
+
+	overlay->pfit_vscale_ratio = ratio;
+}
+
+static int check_overlay_dst(struct intel_overlay *overlay,
+			     struct drm_intel_overlay_put_image *rec)
+{
+	struct drm_display_mode *mode = &overlay->crtc->base.mode;
+
+	if ((rec->dst_x < mode->crtc_hdisplay)
+	    && (rec->dst_x + rec->dst_width
+		    <= mode->crtc_hdisplay)
+	    && (rec->dst_y < mode->crtc_vdisplay)
+	    && (rec->dst_y + rec->dst_height
+		    <= mode->crtc_vdisplay))
+		return 0;
+	else
+		return -EINVAL;
+}
+
+static int check_overlay_scaling(struct put_image_params *rec)
+{
+	u32 tmp;
+
+	/* downscaling limit is 8.0 */
+	tmp = ((rec->src_scan_h << 16) / rec->dst_h) >> 16;
+	if (tmp > 7)
+		return -EINVAL;
+	tmp = ((rec->src_scan_w << 16) / rec->dst_w) >> 16;
+	if (tmp > 7)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int check_overlay_src(struct drm_device *dev,
+			     struct drm_intel_overlay_put_image *rec,
+			     struct drm_gem_object *new_bo)
+{
+	u32 stride_mask;
+	int depth;
+	int uv_hscale = uv_hsubsampling(rec->flags);
+	int uv_vscale = uv_vsubsampling(rec->flags);
+	size_t tmp;
+
+	/* check src dimensions */
+	if (IS_845G(dev) || IS_I830(dev)) {
+		if (rec->src_height > IMAGE_MAX_HEIGHT_LEGACY
+		    || rec->src_width > IMAGE_MAX_WIDTH_LEGACY)
+			return -EINVAL;
+	} else {
+		if (rec->src_height > IMAGE_MAX_HEIGHT
+		    || rec->src_width > IMAGE_MAX_WIDTH)
+			return -EINVAL;
+	}
+	/* better safe than sorry, use 4 as the maximal subsampling ratio */
+	if (rec->src_height < N_VERT_Y_TAPS*4
+	    || rec->src_width < N_HORIZ_Y_TAPS*4)
+		return -EINVAL;
+
+	/* check alingment constrains */
+	switch (rec->flags & I915_OVERLAY_TYPE_MASK) {
+		case I915_OVERLAY_RGB:
+			/* not implemented */
+			return -EINVAL;
+		case I915_OVERLAY_YUV_PACKED:
+			depth = packed_depth_bytes(rec->flags);
+			if (uv_vscale != 1)
+				return -EINVAL;
+			if (depth < 0)
+				return depth;
+			/* ignore UV planes */
+			rec->stride_UV = 0;
+			rec->offset_U = 0;
+			rec->offset_V = 0;
+			/* check pixel alignment */
+			if (rec->offset_Y % depth)
+				return -EINVAL;
+			break;
+		case I915_OVERLAY_YUV_PLANAR:
+			if (uv_vscale < 0 || uv_hscale < 0)
+				return -EINVAL;
+			/* no offset restrictions for planar formats */
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	if (rec->src_width % uv_hscale)
+		return -EINVAL;
+
+	/* stride checking */
+	stride_mask = 63;
+
+	if (rec->stride_Y & stride_mask || rec->stride_UV & stride_mask)
+		return -EINVAL;
+	if (IS_I965G(dev) && rec->stride_Y < 512)
+		return -EINVAL;
+
+	tmp = (rec->flags & I915_OVERLAY_TYPE_MASK) == I915_OVERLAY_YUV_PLANAR ?
+		4 : 8;
+	if (rec->stride_Y > tmp*1024 || rec->stride_UV > 2*1024)
+		return -EINVAL;
+
+	/* check buffer dimensions */
+	switch (rec->flags & I915_OVERLAY_TYPE_MASK) {
+		case I915_OVERLAY_RGB:
+		case I915_OVERLAY_YUV_PACKED:
+			/* always 4 Y values per depth pixels */
+			if (packed_width_bytes(rec->flags, rec->src_width)
+					> rec->stride_Y)
+				return -EINVAL;
+
+			tmp = rec->stride_Y*rec->src_height;
+			if (rec->offset_Y + tmp > new_bo->size)
+				return -EINVAL;
+			break;
+		case I915_OVERLAY_YUV_PLANAR:
+			if (rec->src_width > rec->stride_Y)
+				return -EINVAL;
+			if (rec->src_width/uv_hscale > rec->stride_UV)
+				return -EINVAL;
+
+			tmp = rec->stride_Y*rec->src_height;
+			if (rec->offset_Y + tmp > new_bo->size)
+				return -EINVAL;
+			tmp = rec->stride_UV*rec->src_height;
+			tmp /= uv_vscale;
+			if (rec->offset_U + tmp > new_bo->size
+			    || rec->offset_V + tmp > new_bo->size)
+				return -EINVAL;
+			break;
+	}
+
+	return 0;
+}
+
+int intel_overlay_put_image(struct drm_device *dev, void *data,
+                            struct drm_file *file_priv)
+{
+	struct drm_intel_overlay_put_image *put_image_rec = data;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_overlay *overlay;
+	struct drm_mode_object *drmmode_obj;
+	struct intel_crtc *crtc;
+	struct drm_gem_object *new_bo;
+	struct put_image_params *params;
+	int ret;
+
+	if (!dev_priv) {
+		DRM_ERROR("called with no initialization\n");
+		return -EINVAL;
+	}
+
+	overlay = dev_priv->overlay;
+	if (!overlay) {
+		DRM_DEBUG("userspace bug: no overlay\n");
+		return -ENODEV;
+	}
+
+	if (!(put_image_rec->flags & I915_OVERLAY_ENABLE)) {
+		mutex_lock(&dev->mode_config.mutex);
+		mutex_lock(&dev->struct_mutex);
+
+		ret = intel_overlay_switch_off(overlay);
+
+		mutex_unlock(&dev->struct_mutex);
+		mutex_unlock(&dev->mode_config.mutex);
+
+		return ret;
+	}
+
+	params = kmalloc(sizeof(struct put_image_params), GFP_KERNEL);
+	if (!params)
+		return -ENOMEM;
+
+	drmmode_obj = drm_mode_object_find(dev, put_image_rec->crtc_id,
+                        DRM_MODE_OBJECT_CRTC);
+	if (!drmmode_obj)
+		return -ENOENT;
+	crtc = to_intel_crtc(obj_to_crtc(drmmode_obj));
+
+	new_bo = drm_gem_object_lookup(dev, file_priv,
+			put_image_rec->bo_handle);
+	if (!new_bo)
+		return -ENOENT;
+
+	mutex_lock(&dev->mode_config.mutex);
+	mutex_lock(&dev->struct_mutex);
+
+	if (overlay->crtc != crtc) {
+		struct drm_display_mode *mode = &crtc->base.mode;
+		ret = intel_overlay_switch_off(overlay);
+		if (ret != 0)
+			goto out_unlock;
+
+		ret = check_overlay_possible_on_crtc(overlay, crtc);
+		if (ret != 0)
+			goto out_unlock;
+
+		overlay->crtc = crtc;
+		crtc->overlay = overlay;
+
+		if (intel_panel_fitter_pipe(dev) == crtc->pipe
+		    /* and line to wide, i.e. one-line-mode */
+		    && mode->hdisplay > 1024) {
+			overlay->pfit_active = 1;
+			update_pfit_vscale_ratio(overlay);
+		} else
+			overlay->pfit_active = 0;
+	}
+
+	ret = check_overlay_dst(overlay, put_image_rec);
+	if (ret != 0)
+		goto out_unlock;
+
+	if (overlay->pfit_active) {
+		params->dst_y = ((((u32)put_image_rec->dst_y) << 12) /
+			overlay->pfit_vscale_ratio);
+		/* shifting right rounds downwards, so add 1 */
+		params->dst_h = ((((u32)put_image_rec->dst_height) << 12) /
+			overlay->pfit_vscale_ratio) + 1;
+	} else {
+		params->dst_y = put_image_rec->dst_y;
+		params->dst_h = put_image_rec->dst_height;
+	}
+	params->dst_x = put_image_rec->dst_x;
+	params->dst_w = put_image_rec->dst_width;
+
+	params->src_w = put_image_rec->src_width;
+	params->src_h = put_image_rec->src_height;
+	params->src_scan_w = put_image_rec->src_scan_width;
+	params->src_scan_h = put_image_rec->src_scan_height;
+	if (params->src_scan_h > params->src_h
+	    || params->src_scan_w > params->src_w) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	ret = check_overlay_src(dev, put_image_rec, new_bo);
+	if (ret != 0)
+		goto out_unlock;
+	params->format = put_image_rec->flags & ~I915_OVERLAY_FLAGS_MASK;
+	params->stride_Y = put_image_rec->stride_Y;
+	params->stride_UV = put_image_rec->stride_UV;
+	params->offset_Y = put_image_rec->offset_Y;
+	params->offset_U = put_image_rec->offset_U;
+	params->offset_V = put_image_rec->offset_V;
+
+	/* Check scaling after src size to prevent a divide-by-zero. */
+	ret = check_overlay_scaling(params);
+	if (ret != 0)
+		goto out_unlock;
+
+	ret = intel_overlay_do_put_image(overlay, new_bo, params);
+	if (ret != 0)
+		goto out_unlock;
+
+	mutex_unlock(&dev->struct_mutex);
+	mutex_unlock(&dev->mode_config.mutex);
+
+	kfree(params);
+
+	return 0;
+
+out_unlock:
+	mutex_unlock(&dev->struct_mutex);
+	mutex_unlock(&dev->mode_config.mutex);
+	drm_gem_object_unreference(new_bo);
+	kfree(params);
+
+	return ret;
+}
+
+static void update_reg_attrs(struct intel_overlay *overlay,
+			     struct overlay_registers *regs)
+{
+	regs->OCLRC0 = (overlay->contrast << 18) | (overlay->brightness & 0xff);
+	regs->OCLRC1 = overlay->saturation;
+}
+
+static bool check_gamma_bounds(u32 gamma1, u32 gamma2)
+{
+	int i;
+
+	if (gamma1 & 0xff000000 || gamma2 & 0xff000000)
+		return false;
+
+	for (i = 0; i < 3; i++) {
+		if (((gamma1 >> i * 8) & 0xff) >= ((gamma2 >> i*8) & 0xff))
+			return false;
+	}
+
+	return true;
+}
+
+static bool check_gamma5_errata(u32 gamma5)
+{
+	int i;
+
+	for (i = 0; i < 3; i++) {
+		if (((gamma5 >> i*8) & 0xff) == 0x80)
+			return false;
+	}
+
+	return true;
+}
+
+static int check_gamma(struct drm_intel_overlay_attrs *attrs)
+{
+	if (!check_gamma_bounds(0, attrs->gamma0)
+	    || !check_gamma_bounds(attrs->gamma0, attrs->gamma1)
+	    || !check_gamma_bounds(attrs->gamma1, attrs->gamma2)
+	    || !check_gamma_bounds(attrs->gamma2, attrs->gamma3)
+	    || !check_gamma_bounds(attrs->gamma3, attrs->gamma4)
+	    || !check_gamma_bounds(attrs->gamma4, attrs->gamma5)
+	    || !check_gamma_bounds(attrs->gamma5, 0x00ffffff))
+		return -EINVAL;
+	if (!check_gamma5_errata(attrs->gamma5))
+		return -EINVAL;
+	return 0;
+}
+
+int intel_overlay_attrs(struct drm_device *dev, void *data,
+                        struct drm_file *file_priv)
+{
+	struct drm_intel_overlay_attrs *attrs = data;
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_overlay *overlay;
+	struct overlay_registers *regs;
+	int ret;
+
+	if (!dev_priv) {
+		DRM_ERROR("called with no initialization\n");
+		return -EINVAL;
+	}
+
+	overlay = dev_priv->overlay;
+	if (!overlay) {
+		DRM_DEBUG("userspace bug: no overlay\n");
+		return -ENODEV;
+	}
+
+	mutex_lock(&dev->mode_config.mutex);
+	mutex_lock(&dev->struct_mutex);
+
+	if (!(attrs->flags & I915_OVERLAY_UPDATE_ATTRS)) {
+		attrs->color_key = overlay->color_key;
+		attrs->brightness = overlay->brightness;
+		attrs->contrast = overlay->contrast;
+		attrs->saturation = overlay->saturation;
+
+		if (IS_I9XX(dev)) {
+			attrs->gamma0 = I915_READ(OGAMC0);
+			attrs->gamma1 = I915_READ(OGAMC1);
+			attrs->gamma2 = I915_READ(OGAMC2);
+			attrs->gamma3 = I915_READ(OGAMC3);
+			attrs->gamma4 = I915_READ(OGAMC4);
+			attrs->gamma5 = I915_READ(OGAMC5);
+		}
+		ret = 0;
+	} else {
+		overlay->color_key = attrs->color_key;
+		if (attrs->brightness >= -128 && attrs->brightness <= 127) {
+			overlay->brightness = attrs->brightness;
+		} else {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (attrs->contrast <= 255) {
+			overlay->contrast = attrs->contrast;
+		} else {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (attrs->saturation <= 1023) {
+			overlay->saturation = attrs->saturation;
+		} else {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		regs = intel_overlay_map_regs_atomic(overlay);
+		if (!regs) {
+			ret = -ENOMEM;
+			goto out_unlock;
+		}
+
+		update_reg_attrs(overlay, regs);
+
+		intel_overlay_unmap_regs_atomic(overlay);
+
+		if (attrs->flags & I915_OVERLAY_UPDATE_GAMMA) {
+			if (!IS_I9XX(dev)) {
+				ret = -EINVAL;
+				goto out_unlock;
+			}
+
+			if (overlay->active) {
+				ret = -EBUSY;
+				goto out_unlock;
+			}
+
+			ret = check_gamma(attrs);
+			if (ret != 0)
+				goto out_unlock;
+
+			I915_WRITE(OGAMC0, attrs->gamma0);
+			I915_WRITE(OGAMC1, attrs->gamma1);
+			I915_WRITE(OGAMC2, attrs->gamma2);
+			I915_WRITE(OGAMC3, attrs->gamma3);
+			I915_WRITE(OGAMC4, attrs->gamma4);
+			I915_WRITE(OGAMC5, attrs->gamma5);
+		}
+		ret = 0;
+	}
+
+out_unlock:
+	mutex_unlock(&dev->struct_mutex);
+	mutex_unlock(&dev->mode_config.mutex);
+
+	return ret;
+}
+
+void intel_setup_overlay(struct drm_device *dev)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+	struct intel_overlay *overlay;
+	struct drm_gem_object *reg_bo;
+	struct overlay_registers *regs;
+	int ret;
+
+	if (!OVERLAY_EXISTS(dev))
+		return;
+
+	overlay = kzalloc(sizeof(struct intel_overlay), GFP_KERNEL);
+	if (!overlay)
+		return;
+	overlay->dev = dev;
+
+	reg_bo = drm_gem_object_alloc(dev, PAGE_SIZE);
+	if (!reg_bo)
+		goto out_free;
+	overlay->reg_bo = reg_bo->driver_private;
+
+	if (OVERLAY_NONPHYSICAL(dev)) {
+		ret = i915_gem_object_pin(reg_bo, PAGE_SIZE);
+		if (ret) {
+                        DRM_ERROR("failed to pin overlay register bo\n");
+                        goto out_free_bo;
+                }
+		overlay->flip_addr = overlay->reg_bo->gtt_offset;
+	} else {
+		ret = i915_gem_attach_phys_object(dev, reg_bo,
+				I915_GEM_PHYS_OVERLAY_REGS);
+                if (ret) {
+                        DRM_ERROR("failed to attach phys overlay regs\n");
+                        goto out_free_bo;
+                }
+		overlay->flip_addr = overlay->reg_bo->phys_obj->handle->busaddr;
+	}
+
+	/* init all values */
+	overlay->color_key = 0x0101fe;
+	overlay->brightness = -19;
+	overlay->contrast = 75;
+	overlay->saturation = 146;
+
+	regs = intel_overlay_map_regs_atomic(overlay);
+	if (!regs)
+		goto out_free_bo;
+
+	memset(regs, 0, sizeof(struct overlay_registers));
+	update_polyphase_filter(regs);
+
+	update_reg_attrs(overlay, regs);
+
+	intel_overlay_unmap_regs_atomic(overlay);
+
+	dev_priv->overlay = overlay;
+	DRM_INFO("initialized overlay support\n");
+	return;
+
+out_free_bo:
+	drm_gem_object_unreference(reg_bo);
+out_free:
+	kfree(overlay);
+	return;
+}
+
+void intel_cleanup_overlay(struct drm_device *dev)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+
+	if (dev_priv->overlay) {
+		/* The bo's should be free'd by the generic code already.
+		 * Furthermore modesetting teardown happens beforehand so the
+		 * hardware should be off already */
+		BUG_ON(dev_priv->overlay->active);
+
+		kfree(dev_priv->overlay);
+	}
+}

include/drm/i915_drm.h

@@ -186,6 +186,8 @@ typedef struct _drm_i915_sarea {
 #define DRM_I915_GEM_MMAP_GTT	0x24
 #define DRM_I915_GET_PIPE_FROM_CRTC_ID	0x25
 #define DRM_I915_GEM_MADVISE	0x26
+#define DRM_I915_OVERLAY_PUT_IMAGE	0x27
+#define DRM_I915_OVERLAY_ATTRS	0x28
 
 #define DRM_IOCTL_I915_INIT		DRM_IOW( DRM_COMMAND_BASE + DRM_I915_INIT, drm_i915_init_t)
 #define DRM_IOCTL_I915_FLUSH		DRM_IO ( DRM_COMMAND_BASE + DRM_I915_FLUSH)
@@ -223,6 +225,8 @@ typedef struct _drm_i915_sarea {
 #define DRM_IOCTL_I915_GEM_GET_APERTURE	DRM_IOR  (DRM_COMMAND_BASE + DRM_I915_GEM_GET_APERTURE, struct drm_i915_gem_get_aperture)
 #define DRM_IOCTL_I915_GET_PIPE_FROM_CRTC_ID DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GET_PIPE_FROM_CRTC_ID, struct drm_intel_get_pipe_from_crtc_id)
 #define DRM_IOCTL_I915_GEM_MADVISE	DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_GEM_MADVISE, struct drm_i915_gem_madvise)
+#define DRM_IOCTL_I915_OVERLAY_PUT_IMAGE	DRM_IOW(DRM_COMMAND_BASE + DRM_IOCTL_I915_OVERLAY_ATTRS, struct drm_intel_overlay_put_image)
+#define DRM_IOCTL_I915_OVERLAY_ATTRS	DRM_IOWR(DRM_COMMAND_BASE + DRM_I915_OVERLAY_ATTRS, struct drm_intel_overlay_attrs)
 
 /* Allow drivers to submit batchbuffers directly to hardware, relying
  * on the security mechanisms provided by hardware.
@@ -266,6 +270,7 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_CHIPSET_ID            4
 #define I915_PARAM_HAS_GEM               5
 #define I915_PARAM_NUM_FENCES_AVAIL      6
+#define I915_PARAM_HAS_OVERLAY           7
 
 typedef struct drm_i915_getparam {
 	int param;
@@ -686,4 +691,70 @@ struct drm_i915_gem_madvise {
 	__u32 retained;
 };
 
+/* flags */
+#define I915_OVERLAY_TYPE_MASK 		0xff
+#define I915_OVERLAY_YUV_PLANAR 	0x01
+#define I915_OVERLAY_YUV_PACKED 	0x02
+#define I915_OVERLAY_RGB		0x03
+
+#define I915_OVERLAY_DEPTH_MASK		0xff00
+#define I915_OVERLAY_RGB24		0x1000
+#define I915_OVERLAY_RGB16		0x2000
+#define I915_OVERLAY_RGB15		0x3000
+#define I915_OVERLAY_YUV422		0x0100
+#define I915_OVERLAY_YUV411		0x0200
+#define I915_OVERLAY_YUV420		0x0300
+#define I915_OVERLAY_YUV410		0x0400
+
+#define I915_OVERLAY_SWAP_MASK		0xff0000
+#define I915_OVERLAY_NO_SWAP		0x000000
+#define I915_OVERLAY_UV_SWAP		0x010000
+#define I915_OVERLAY_Y_SWAP		0x020000
+#define I915_OVERLAY_Y_AND_UV_SWAP	0x030000
+
+#define I915_OVERLAY_FLAGS_MASK		0xff000000
+#define I915_OVERLAY_ENABLE		0x01000000
+
+struct drm_intel_overlay_put_image {
+	/* various flags and src format description */
+	__u32 flags;
+	/* source picture description */
+	__u32 bo_handle;
+	/* stride values and offsets are in bytes, buffer relative */
+	__u16 stride_Y; /* stride for packed formats */
+	__u16 stride_UV;
+	__u32 offset_Y; /* offset for packet formats */
+	__u32 offset_U;
+	__u32 offset_V;
+	/* in pixels */
+	__u16 src_width;
+	__u16 src_height;
+	/* to compensate the scaling factors for partially covered surfaces */
+	__u16 src_scan_width;
+	__u16 src_scan_height;
+	/* output crtc description */
+	__u32 crtc_id;
+	__u16 dst_x;
+	__u16 dst_y;
+	__u16 dst_width;
+	__u16 dst_height;
+};
+
+/* flags */
+#define I915_OVERLAY_UPDATE_ATTRS	(1<<0)
+#define I915_OVERLAY_UPDATE_GAMMA	(1<<1)
+struct drm_intel_overlay_attrs {
+	__u32 flags;
+	__u32 color_key;
+	__s32 brightness;
+	__u32 contrast;
+	__u32 saturation;
+	__u32 gamma0;
+	__u32 gamma1;
+	__u32 gamma2;
+	__u32 gamma3;
+	__u32 gamma4;
+	__u32 gamma5;
+};
+
 #endif				/* _I915_DRM_H_ */