i965: Export format comparison for blitting between miptrees

Since the introduction of

commit 536003c11e4cb1172c540932ce3cce06f03bf44e
Author: Boyan Ding <boyan.j.ding@gmail.com>
Date:   Wed Mar 25 19:36:54 2015 +0800

    i965: Add XRGB8888 format to intel_screen_make_configs

winsys buffers no longer have an alpha channel. This causes
_mesa_format_matches_format_and_type() to reject previously working BGRA
uploads from using the BLT fast path. Instead of using the generic
routine for matching formats exactly, export the slightly more relaxed
check from intel_miptree_blit() which importantly allows the blitter
routine to apply a small number of format conversions.

References: https://bugs.freedesktop.org/show_bug.cgi?id=90839
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Alexander Monakov <amonakov@gmail.com>
Cc: Kristian Høgsberg <krh@bitplanet.net>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: mesa-stable@lists.freedesktop.org
(cherry picked from commit 922c0c9fd526ce19b87bc74a3159dec7705c1de1)
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>

Conflicts:
	src/mesa/drivers/dri/i965/intel_pixel_draw.c

3 files changed, 14 insertions, 5 deletions

diff --git a/src/mesa/drivers/dri/i965/intel_blit.c b/src/mesa/drivers/dri/i965/intel_blit.c
index efdbfe7ca55..6b04adf2e5c 100644
--- a/src/mesa/drivers/dri/i965/intel_blit.c
+++ b/src/mesa/drivers/dri/i965/intel_blit.c
@@ -139,8 +139,8 @@ blt_pitch(struct intel_mipmap_tree *mt)
    return pitch;
 }
 
-static bool
-blt_compatible_formats(mesa_format src, mesa_format dst)
+bool
+intel_miptree_blit_compatible_formats(mesa_format src, mesa_format dst)
 {
    /* The BLT doesn't handle sRGB conversion */
    assert(src == _mesa_get_srgb_format_linear(src));
@@ -206,7 +206,7 @@ intel_miptree_blit(struct brw_context *brw,
     * the X channel don't matter), and XRGB8888 to ARGB8888 by setting the A
     * channel to 1.0 at the end.
     */
-   if (!blt_compatible_formats(src_format, dst_format)) {
+   if (!intel_miptree_blit_compatible_formats(src_format, dst_format)) {
       perf_debug("%s: Can't use hardware blitter from %s to %s, "
                  "falling back.\n", __FUNCTION__,
                  _mesa_get_format_name(src_format),
diff --git a/src/mesa/drivers/dri/i965/intel_blit.h b/src/mesa/drivers/dri/i965/intel_blit.h
index f563939fdd9..2287c379c4e 100644
--- a/src/mesa/drivers/dri/i965/intel_blit.h
+++ b/src/mesa/drivers/dri/i965/intel_blit.h
@@ -46,6 +46,8 @@ intelEmitCopyBlit(struct brw_context *brw,
                               GLshort w, GLshort h,
 			      GLenum logicop );
 
+bool intel_miptree_blit_compatible_formats(mesa_format src, mesa_format dst);
+
 bool intel_miptree_blit(struct brw_context *brw,
                         struct intel_mipmap_tree *src_mt,
                         int src_level, int src_slice,
diff --git a/src/mesa/drivers/dri/i965/intel_pixel_draw.c b/src/mesa/drivers/dri/i965/intel_pixel_draw.c
index e0904de2ba3..e0ff6582829 100644
--- a/src/mesa/drivers/dri/i965/intel_pixel_draw.c
+++ b/src/mesa/drivers/dri/i965/intel_pixel_draw.c
@@ -28,6 +28,7 @@
 #include "main/glheader.h"
 #include "main/enums.h"
 #include "main/image.h"
+#include "main/glformats.h"
 #include "main/mtypes.h"
 #include "main/condrender.h"
 #include "main/fbobject.h"
@@ -76,8 +77,14 @@ do_blit_drawpixels(struct gl_context * ctx,
    struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];
    struct intel_renderbuffer *irb = intel_renderbuffer(rb);
 
-   if (!_mesa_format_matches_format_and_type(irb->mt->format, format, type,
-                                             false)) {
+   mesa_format src_format = _mesa_format_from_format_and_type(format, type);
+   mesa_format dst_format = irb->mt->format;
+
+   /* We can safely discard sRGB encode/decode for the DrawPixels interface */
+   src_format = _mesa_get_srgb_format_linear(src_format);
+   dst_format = _mesa_get_srgb_format_linear(dst_format);
+
+   if (!intel_miptree_blit_compatible_formats(src_format, dst_format)) {
       DBG("%s: bad format for blit\n", __FUNCTION__);
       return false;
    }