xserver: Branch 'master'

[Adam Jackson]

 exa/exa_unaccel.c |   35 ++++++++++++++++++++++++++---------
 1 files changed, 26 insertions(+), 9 deletions(-)

New commits:
diff-tree 486fd4145aed93093d1f1655de40c0a8582bb8b1 (from 50cb6c7e4419e067c1f080d1de940811d21fc725)
Author: Adam Jackson <ajax at benzedrine.nwnk.net>
Date:   Fri Jul 27 13:10:39 2007 -0400

    exaGetPixmapFirstPixel: avoid framebuffer readbacks if possible.
    
    If the pixel in framebuffer memory isn't modified since we uploaded it, we
    can just read from the system memory copy, wihch avoids both a readback and
    an accelerator stall.
    
    In principle this function is still wrong, and all the framebuffer pixel
    access should be going through (w)fb so we can get pixel layout corrections.

diff --git a/exa/exa_unaccel.c b/exa/exa_unaccel.c
index 708d1ea..b67ea63 100644
--- a/exa/exa_unaccel.c
+++ b/exa/exa_unaccel.c
@@ -369,31 +369,48 @@ ExaCheckComposite (CARD8      op,
 /**
  * Gets the 0,0 pixel of a pixmap.  Used for doing solid fills of tiled pixmaps
  * that happen to be 1x1.  Pixmap must be at least 8bpp.
+ *
+ * XXX This really belongs in fb, so it can be aware of tiling and etc.
  */
 CARD32
 exaGetPixmapFirstPixel (PixmapPtr pPixmap)
 {
     CARD32 pixel;
+    void *fb;
+    Bool need_finish = FALSE;
+    BoxRec box;
     ExaMigrationRec pixmaps[1];
+    ExaPixmapPriv (pPixmap);
 
-    pixmaps[0].as_dst = FALSE;
-    pixmaps[0].as_src = TRUE;
-    pixmaps[0].pPix = pPixmap;
-    exaDoMigration (pixmaps, 1, FALSE);
+    /* Try to avoid framebuffer readbacks */
+    if (exaPixmapIsOffscreen(pPixmap)) {
+	if (!miPointInRegion(DamageRegion(pExaPixmap->pDamage), 0, 0,  &box)) {
+	    fb = pExaPixmap->sys_ptr;
+	} else {
+	    need_finish = TRUE;
+	    fb = pPixmap->devPrivate.ptr;
+	    pixmaps[0].as_dst = FALSE;
+	    pixmaps[0].as_src = TRUE;
+	    pixmaps[0].pPix = pPixmap;
+	    exaDoMigration (pixmaps, 1, FALSE);
+	    exaPrepareAccess(&pPixmap->drawable, EXA_PREPARE_SRC);
+	}
+    }
 
-    exaPrepareAccess(&pPixmap->drawable, EXA_PREPARE_SRC);
     switch (pPixmap->drawable.bitsPerPixel) {
     case 32:
-	pixel = *(CARD32 *)(pPixmap->devPrivate.ptr);
+	pixel = *(CARD32 *)fb;
 	break;
     case 16:
-	pixel = *(CARD16 *)(pPixmap->devPrivate.ptr);
+	pixel = *(CARD16 *)fb;
 	break;
     default:
-	pixel = *(CARD8 *)(pPixmap->devPrivate.ptr);
+	pixel = *(CARD8 *)fb;
 	break;
     }
-    exaFinishAccess(&pPixmap->drawable, EXA_PREPARE_SRC);
+
+    if (need_finish)
+	exaFinishAccess(&pPixmap->drawable, EXA_PREPARE_SRC);
 
     return pixel;
 }