sna/gen6+: Discourage use of the BLT with Y-tiling

Somewhere, somehow the first glyph character upload into the Y-tiled
glyph cache is corrupt since

commit 75d87762471e195dddd73056fc6a06e17db1c8b0
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Apr 17 10:29:28 2015 +0100

    sna: Enable blitting with Y-tiled surfaces

I have not spotted whether it is a missing magic bit or a bad GTT path,
but ideally we don't want to switch to BLT along that path anyway (since
we are in the middle of rendering with the other engine).

Reported-by: Andy Furniss <adf.lists@gmail.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=90138
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 44 insertions, 21 deletions

diff --git a/src/sna/gen8_render.c b/src/sna/gen8_render.c
index c0fe9f9c..b40c582a 100644
--- a/src/sna/gen8_render.c
+++ b/src/sna/gen8_render.c
@@ -2029,55 +2029,78 @@ gen8_composite_set_target(struct sna *sna,
 
 static bool
 try_blt(struct sna *sna,
-	PicturePtr dst, PicturePtr src,
-	int width, int height)
+	uint8_t op,
+	PicturePtr src,
+	PicturePtr mask,
+	PicturePtr dst,
+	int16_t src_x, int16_t src_y,
+	int16_t msk_x, int16_t msk_y,
+	int16_t dst_x, int16_t dst_y,
+	int16_t width, int16_t height,
+	unsigned flags,
+	struct sna_composite_op *tmp)
 {
 	struct kgem_bo *bo;
 
 	if (sna->kgem.mode == KGEM_BLT) {
 		DBG(("%s: already performing BLT\n", __FUNCTION__));
-		return true;
+		goto execute;
 	}
 
 	if (too_large(width, height)) {
 		DBG(("%s: operation too large for 3D pipe (%d, %d)\n",
 		     __FUNCTION__, width, height));
-		return true;
+		goto execute;
 	}
 
 	bo = __sna_drawable_peek_bo(dst->pDrawable);
 	if (bo == NULL)
-		return true;
+		goto execute;
 
 	if (untiled_tlb_miss(bo))
-		return true;
+		goto execute;
+
+	if (bo->rq) {
+		if (RQ_IS_BLT(bo->rq))
+			goto execute;
+
+		return false;
+	}
 
-	if (bo->rq)
-		return RQ_IS_BLT(bo->rq);
+	if (bo->tiling == I915_TILING_Y)
+		goto upload;
 
 	if (sna_picture_is_solid(src, NULL) && can_switch_to_blt(sna, bo, 0))
-		return true;
+		goto execute;
 
 	if (src->pDrawable == dst->pDrawable &&
 	    (sna->render_state.gt < 3 || width*height < 1024) &&
 	    can_switch_to_blt(sna, bo, 0))
-		return true;
+		goto execute;
 
 	if (src->pDrawable) {
 		struct kgem_bo *s = __sna_drawable_peek_bo(src->pDrawable);
 		if (s == NULL)
-			return true;
+			goto upload;
 
 		if (prefer_blt_bo(sna, s, bo))
-			return true;
+			goto execute;
 	}
 
 	if (sna->kgem.ring == KGEM_BLT) {
 		DBG(("%s: already performing BLT\n", __FUNCTION__));
-		return true;
+		goto execute;
 	}
 
-	return false;
+upload:
+	flags |= COMPOSITE_UPLOAD;
+execute:
+	return sna_blt_composite(sna, op,
+				 src, dst,
+				 src_x, src_y,
+				 dst_x, dst_y,
+				 width, height,
+				 flags, tmp);
 }
 
 static bool
@@ -2307,13 +2330,13 @@ gen8_render_composite(struct sna *sna,
 	     width, height, sna->kgem.mode, sna->kgem.ring));
 
 	if (mask == NULL &&
-	    try_blt(sna, dst, src, width, height) &&
-	    sna_blt_composite(sna, op,
-			      src, dst,
-			      src_x, src_y,
-			      dst_x, dst_y,
-			      width, height,
-			      flags, tmp))
+	    try_blt(sna, op,
+		    src, mask, dst,
+		    src_x, src_y,
+		    msk_x, msk_y,
+		    dst_x, dst_y,
+		    width, height,
+		    flags, tmp))
 		return true;
 
 	if (gen8_composite_fallback(sna, src, mask, dst))