Scanline wait hack for IVB

[Jesse Barnes <jbarnes@virtuousgeek.org>]

You need to set DE_RRMR (offset 0x44050) to unmask scanline waits, but
this at least doesn't hang on my IVB.

However I still see tearing on my config, need to verify the pipe and
inclusive/exclusive setting.

-- 
Jesse Barnes, Intel Open Source Technology Center

diff --git a/src/i830_reg.h b/src/i830_reg.h
index 93d03cf..bd2980a 100644
--- a/src/i830_reg.h
+++ b/src/i830_reg.h
@@ -52,19 +52,39 @@
 
 /* Wait for Events */
 #define MI_WAIT_FOR_EVENT			(0x03<<23)
+#define MI_WAIT_FOR_PIPEC_SVBLANK_SNB		(1<<21)
+#define MI_WAIT_FOR_PIPEB_SVBLANK_SNB		(1<<11)
+#define MI_WAIT_FOR_PIPEA_SVBLANK_SNB		(1<<3)
 #define MI_WAIT_FOR_PIPEB_SVBLANK		(1<<18)
 #define MI_WAIT_FOR_PIPEA_SVBLANK		(1<<17)
 #define MI_WAIT_FOR_OVERLAY_FLIP		(1<<16)
+#define MI_WAIT_FOR_PIPEC_SCAN_LINE_WINDOW_SNB	(1<<14)
 #define MI_WAIT_FOR_PIPEB_VBLANK		(1<<7)
 #define MI_WAIT_FOR_PIPEB_SCAN_LINE_WINDOW	(1<<5)
+#define MI_WAIT_FOR_PIPEB_SCAN_LINE_WINDOW_SNB	(1<<8)
 #define MI_WAIT_FOR_PIPEA_VBLANK		(1<<3)
 #define MI_WAIT_FOR_PIPEA_SCAN_LINE_WINDOW	(1<<1)
+#define MI_WAIT_FOR_PIPEA_SCAN_LINE_WINDOW_SNB	(1<<0)
 
 /* Set the scan line for MI_WAIT_FOR_PIPE?_SCAN_LINE_WINDOW */
 #define MI_LOAD_SCAN_LINES_INCL			(0x12<<23)
 #define MI_LOAD_SCAN_LINES_DISPLAY_PIPEA	(0)
 #define MI_LOAD_SCAN_LINES_DISPLAY_PIPEB	(0x1<<20)
 
+#define MI_LOAD_SCAN_LINES_EXCL			(0x13<<23)
+#define MI_LOAD_SCAN_LINES_EXCL_PIPEA		(0)
+#define MI_LOAD_SCAN_LINES_EXCL_PIPEB		(1<<19)
+#define MI_LOAD_SCAN_LINES_EXCL_PIPEC		(4<<19)
+
+#define _PIPE(pipe, a, b) ((a) + (pipe)*((b)-(a)))
+
+#define _DE_LOAD_SL_A				0x70068
+#define _DE_LOAD_SL_B				0x71068
+#define _DE_LOAD_SL_C				0x72068
+#define DE_LOAD_SL(pipe) _PIPE(pipe, _DE_LOAD_SL_A, _DE_LOAD_SL_B)
+
+#define MI_LOAD_REGISTER_IMM			(0x22<<23 | 1)
+
 /* BLT commands */
 #define COLOR_BLT_CMD		((2<<29)|(0x40<<22)|(0x3))
 #define COLOR_BLT_WRITE_ALPHA	(1<<21)
diff --git a/src/intel_dri.c b/src/intel_dri.c
index f6f0c86..87633e2 100644
--- a/src/intel_dri.c
+++ b/src/intel_dri.c
@@ -625,6 +625,65 @@ I830DRI2CopyRegion(DrawablePtr drawable, RegionPtr pRegion,
 			OUT_BATCH(MI_WAIT_FOR_EVENT | event);
 			ADVANCE_BATCH();
 		}
+	} else if (pixmap_is_scanout(get_drawable_pixmap(dst)) &&
+		   intel->swapbuffers_wait && INTEL_INFO(intel)->gen >= 60) {
+		BoxPtr box;
+		BoxRec crtcbox;
+		int y1, y2;
+		int pipe = -1, event, load_scan_lines_reg;
+		xf86CrtcPtr crtc;
+		Bool full_height = FALSE;
+
+		box = REGION_EXTENTS(unused, gc->pCompositeClip);
+		crtc = intel_covering_crtc(scrn, box, NULL, &crtcbox);
+
+		/*
+		 * Make sure the CRTC is valid and this is the real front
+		 * buffer
+		 */
+		if (crtc != NULL && !crtc->rotatedData) {
+			pipe = intel_crtc_to_pipe(crtc);
+
+			load_scan_lines_reg = DE_LOAD_SL(pipe);
+
+			/*
+			 * Make sure we don't wait for a scanline that will
+			 * never occur
+			 */
+			y1 = (crtcbox.y1 <= box->y1) ? box->y1 - crtcbox.y1 : 0;
+			y2 = (box->y2 <= crtcbox.y2) ?
+			    box->y2 - crtcbox.y1 : crtcbox.y2 - crtcbox.y1;
+
+			if (y1 == 0 && y2 == (crtcbox.y2 - crtcbox.y1))
+			    full_height = TRUE;
+
+			if (pipe == 0) {
+				event = MI_WAIT_FOR_PIPEA_SCAN_LINE_WINDOW_SNB;
+				if (full_height)
+				    event = MI_WAIT_FOR_PIPEA_SVBLANK_SNB;
+			} else if (pipe == 1) {
+				event = MI_WAIT_FOR_PIPEB_SCAN_LINE_WINDOW_SNB;
+				if (full_height)
+				    event = MI_WAIT_FOR_PIPEB_SVBLANK_SNB;
+			} else {
+				event = MI_WAIT_FOR_PIPEC_SCAN_LINE_WINDOW_SNB;
+				if (full_height)
+				    event = MI_WAIT_FOR_PIPEC_SVBLANK_SNB;
+			}
+
+			if (crtc->mode.Flags & V_INTERLACE) {
+				/* DSL count field lines */
+				y1 /= 2;
+				y2 /= 2;
+			}
+
+			BEGIN_BATCH_BLT(4);
+			OUT_BATCH(MI_LOAD_REGISTER_IMM);
+			OUT_BATCH(load_scan_lines_reg);
+			OUT_BATCH((1<<31) | (1<<30) | (y1 << 16) | (y2-1));
+			OUT_BATCH(MI_WAIT_FOR_EVENT | event);
+			ADVANCE_BATCH();
+		}
 	}
 
 	/* It's important that this copy gets submitted before the