gallium/radeon: use staging for texture read mappings from GTT WC

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

diff --git a/src/gallium/drivers/radeon/r600_texture.c b/src/gallium/drivers/radeon/r600_texture.c
index 55c8e6f..5d84eb4 100644 (file)
--- a/src/gallium/drivers/radeon/r600_texture.c
+++ b/src/gallium/drivers/radeon/r600_texture.c
@@ -1456,8 +1456,8 @@ static void *r600_texture_transfer_map(struct pipe_context *ctx,
                /* Tiled textures need to be converted into a linear texture for CPU
                 * access. The staging texture is always linear and is placed in GART.
                 *
-                * Reading from VRAM is slow, always use the staging texture in
-                * this case.
+                * Reading from VRAM or GTT WC is slow, always use the staging
+                * texture in this case.
                 *
                 * Use the staging texture for uploads if the underlying BO
                 * is busy.
@@ -1465,8 +1465,9 @@ static void *r600_texture_transfer_map(struct pipe_context *ctx,
                if (!rtex->surface.is_linear)
                        use_staging_texture = true;
                else if (usage & PIPE_TRANSFER_READ)
-                       use_staging_texture = (rtex->resource.domains &
-                                              RADEON_DOMAIN_VRAM) != 0;
+                       use_staging_texture =
+                               rtex->resource.domains & RADEON_DOMAIN_VRAM ||
+                               rtex->resource.flags & RADEON_FLAG_GTT_WC;
                /* Write & linear only: */
                else if (r600_rings_is_buffer_referenced(rctx, rtex->resource.buf,
                                                         RADEON_USAGE_READWRITE) ||