vivante: include alpha channel in pixmaps

Always include the alpha channel in pixmap operations.

This required as the blit can be used to upload images to the
pixmaps which back a Xrender picture, where the alpha channel must
be preserved, and because the 2D PE2.0 engine will avoid copying
those bits.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/vivante.c b/src/vivante.c
index ff42a79..609730b 100644
--- a/src/vivante.c
+++ b/src/vivante.c
@@ -86,18 +86,19 @@ void vivante_set_pixmap_bo(PixmapPtr pixmap, struct drm_armada_bo *bo)
 
 		/*
 		 * This is an imprecise conversion to the Vivante GAL format.
-		 * One important thing here is that Pixmaps don't have an
-		 * alpha channel.
+		 * Although pixmaps in X generally don't have an alpha channel,
+		 * we must set the format to include the alpha channel to
+		 * ensure that the GPU copies all the bits.
 		 */
 		switch (pixmap->drawable.bitsPerPixel) {
 		case 16:
 			if (pixmap->drawable.depth == 15)
-				format = gcvSURF_X1R5G5B5;
+				format = gcvSURF_A1R5G5B5;
 			else
 				format = gcvSURF_R5G6B5;
 			break;
 		case 32:
-			format = gcvSURF_X8R8G8B8;
+			format = gcvSURF_A8R8G8B8;
 			break;
 		default:
 			goto fail;