From: Michel D?nzer <michel.daen...@amd.com>
Signed-off-by: Michel D?nzer <michel.daenzer at amd.com>
---
src/gallium/drivers/radeon/r600_buffer_common.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/src/gallium/drivers/radeon/r600_buffer_common.c
b/src/gallium/drivers/radeon/r600_buffer_common.c
index 4e6b897..154c33d 100644
--- a/src/gallium/drivers/radeon/r600_buffer_common.c
+++ b/src/gallium/drivers/radeon/r600_buffer_common.c
@@ -127,13 +127,17 @@ bool r600_init_resource(struct r600_common_screen
*rscreen,
break;
}
- /* Use GTT for all persistent mappings, because they are
- * always cached and coherent. */
- if (res->b.b.target == PIPE_BUFFER &&
+ /* Use GTT for all persistent mappings with older kernels, because they
+ * didn't always flush the HDP cache before CS execution.
+ *
+ * Write-combined CPU mappings are fine, the kernel ensures all CPU
+ * writes finish before the GPU executes a command stream.
+ */
+ if (rscreen->info.drm_minor < 40 &&
+ res->b.b.target == PIPE_BUFFER &&
res->b.b.flags & (PIPE_RESOURCE_FLAG_MAP_PERSISTENT |
PIPE_RESOURCE_FLAG_MAP_COHERENT)) {
res->domains = RADEON_DOMAIN_GTT;
- flags = 0;
}
/* Tiled textures are unmappable. Always put them in VRAM. */
--
2.0.1
