6 files changed, 21 insertions, 0 deletions
diff --git a/src/gallium/drivers/r300/r300_screen.c b/src/gallium/drivers/r300/r300_screen.c
index 26d73e47ccd..0977d3920a3 100644
--- a/src/gallium/drivers/r300/r300_screen.c
+++ b/src/gallium/drivers/r300/r300_screen.c
@@ -106,6 +106,7 @@ static int r300_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
         case PIPE_CAP_USER_INDEX_BUFFERS:
         case PIPE_CAP_USER_CONSTANT_BUFFERS:
         case PIPE_CAP_PREFER_BLIT_BASED_TEXTURE_TRANSFER:
+        case PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT:
             return 1;
 
         case PIPE_CAP_MIN_MAP_BUFFER_ALIGNMENT:
diff --git a/src/gallium/drivers/r300/r300_state.c b/src/gallium/drivers/r300/r300_state.c
index 048672c5f61..5472263781e 100644
--- a/src/gallium/drivers/r300/r300_state.c
+++ b/src/gallium/drivers/r300/r300_state.c
@@ -2129,6 +2129,10 @@ static void r300_texture_barrier(struct pipe_context *pipe)
     r300_mark_atom_dirty(r300, &r300->texture_cache_inval);
 }
 
+static void r300_memory_barrier(struct pipe_context *pipe, unsigned flags)
+{
+}
+
 void r300_init_state_functions(struct r300_context* r300)
 {
     r300->context.create_blend_state = r300_create_blend_state;
@@ -2189,4 +2193,5 @@ void r300_init_state_functions(struct r300_context* r300)
     r300->context.delete_vs_state = r300_delete_vs_state;
 
     r300->context.texture_barrier = r300_texture_barrier;
+    r300->context.memory_barrier = r300_memory_barrier;
 }
diff --git a/src/gallium/drivers/r600/r600_pipe.c b/src/gallium/drivers/r600/r600_pipe.c
index 630e21d3484..f2782e6baa0 100644
--- a/src/gallium/drivers/r600/r600_pipe.c
+++ b/src/gallium/drivers/r600/r600_pipe.c
@@ -355,6 +355,7 @@ static int r600_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
         case PIPE_CAP_PREFER_BLIT_BASED_TEXTURE_TRANSFER:
 	case PIPE_CAP_QUERY_PIPELINE_STATISTICS:
 	case PIPE_CAP_TEXTURE_MULTISAMPLE:
+        case PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT:
 		return 1;
 
 	case PIPE_CAP_TGSI_TEXCOORD:
diff --git a/src/gallium/drivers/radeon/r600_buffer_common.c b/src/gallium/drivers/radeon/r600_buffer_common.c
index e75b3371f59..340ebb2bcd5 100644
--- a/src/gallium/drivers/radeon/r600_buffer_common.c
+++ b/src/gallium/drivers/radeon/r600_buffer_common.c
@@ -122,6 +122,14 @@ 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 &&
+	    res->b.b.flags & (PIPE_RESOURCE_FLAG_MAP_PERSISTENT |
+			      PIPE_RESOURCE_FLAG_MAP_COHERENT)) {
+		res->domains = RADEON_DOMAIN_GTT;
+	}
+
 	/* Tiled textures are unmappable. Always put them in VRAM. */
 	if (res->b.b.target != PIPE_BUFFER &&
 	    rtex->surface.level[0].mode >= RADEON_SURF_MODE_1D) {
diff --git a/src/gallium/drivers/radeon/r600_pipe_common.c b/src/gallium/drivers/radeon/r600_pipe_common.c
index dbca157f04a..f38e333ebd3 100644
--- a/src/gallium/drivers/radeon/r600_pipe_common.c
+++ b/src/gallium/drivers/radeon/r600_pipe_common.c
@@ -39,6 +39,10 @@
  * pipe_context
  */
 
+static void r600_memory_barrier(struct pipe_context *ctx, unsigned flags)
+{
+}
+
 bool r600_common_context_init(struct r600_common_context *rctx,
 			      struct r600_common_screen *rscreen)
 {
@@ -56,6 +60,7 @@ bool r600_common_context_init(struct r600_common_context *rctx,
 	rctx->b.transfer_flush_region = u_default_transfer_flush_region;
 	rctx->b.transfer_unmap = u_transfer_unmap_vtbl;
 	rctx->b.transfer_inline_write = u_default_transfer_inline_write;
+        rctx->b.memory_barrier = r600_memory_barrier;
 
 	r600_streamout_init(rctx);
 	r600_query_init(rctx);
diff --git a/src/gallium/drivers/radeonsi/si_pipe.c b/src/gallium/drivers/radeonsi/si_pipe.c
index c69be584c2f..ff11a67b7b1 100644
--- a/src/gallium/drivers/radeonsi/si_pipe.c
+++ b/src/gallium/drivers/radeonsi/si_pipe.c
@@ -252,6 +252,7 @@ static int si_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
 	case PIPE_CAP_TEXTURE_BUFFER_OBJECTS:
         case PIPE_CAP_TGSI_VS_LAYER:
 	case PIPE_CAP_QUERY_PIPELINE_STATISTICS:
+	case PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT:
 		return 1;
 
 	case PIPE_CAP_TEXTURE_MULTISAMPLE: