etnaviv: Cannot render to rb-swapped formats

Commit Message

Wladimir J. van der Laan Dec. 7, 2016, 1:13 p.m. UTC

Exposing rb swapped (or other swizzled) formats for rendering would
involve swizzing in the pixel shader. This is not the case at the
moment, so reject requests for creating such surfaces.

(GPUs that need an extra resolve step anyway due to multiple pixel
pipes, such as gc2000, might also do this swap in the resolve operation.
But this would be tricky to keep track of)
---
 src/gallium/drivers/etnaviv/etnaviv_screen.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

Patch

diff --git a/src/gallium/drivers/etnaviv/etnaviv_screen.c b/src/gallium/drivers/etnaviv/etnaviv_screen.c
index c3f270d..06327b6 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_screen.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_screen.c
@@ -464,8 +464,11 @@  etna_screen_is_format_supported(struct pipe_screen *pscreen,
       return FALSE;
 
    if (usage & PIPE_BIND_RENDER_TARGET) {
-      /* if render target, must be RS-supported format */
-      if (translate_rs_format(format) != ETNA_NO_MATCH) {
+      /* If render target, must be RS-supported format that is not rb swapped.
+       * Exposing rb swapped (or other swizzled) formats for rendering would
+       * involve swizzing in the pixel shader.
+       */
+      if (translate_rs_format(format) != ETNA_NO_MATCH && !translate_rs_format_rb_swap(format)) {
          /* Validate MSAA; number of samples must be allowed, and render target
           * must have MSAA'able format. */
          if (sample_count > 1) {