i965/gen9: Don't do fast clears when GL_FRAMEBUFFER_SRGB is enabled

When GL_FRAMEBUFFER_SRGB is enabled any single-sampled renderbuffers
are resolved in intel_update_state because the hardware can't cope
with fast clears on SRGB buffers. In that case it's pointless to do a
fast clear because it will just be immediately resolved.

Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>

diff --git a/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c b/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c
index a8b16b6d79ebc28985644d854af8403234928fca..735d82495d8cbd37da1b5732d47f1e7f644a9ea0 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c
+++ b/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c
@@ -603,6 +603,17 @@ brw_meta_fast_clear(struct brw_context *brw, struct gl_framebuffer *fb,
           brw->render_target_format[irb->mt->format])
          clear_type = REP_CLEAR;
 
+      /* Gen9 doesn't support fast clear on single-sampled SRGB buffers. When
+       * GL_FRAMEBUFFER_SRGB is enabled any color renderbuffers will be
+       * resolved in intel_update_state. In that case it's pointless to do a
+       * fast clear because it's very likely to be immediately resolved.
+       */
+      if (brw->gen >= 9 &&
+          irb->mt->num_samples <= 1 &&
+          brw->ctx.Color.sRGBEnabled &&
+          _mesa_get_srgb_format_linear(irb->mt->format) != irb->mt->format)
+         clear_type = REP_CLEAR;
+
       if (irb->mt->fast_clear_state == INTEL_FAST_CLEAR_STATE_NO_MCS)
          clear_type = REP_CLEAR;