radeonsi: add support for sampler views where resource = NULL

The hardware obeys swizzles even if the resource is NULL.
This will be used by set_polygon_stipple.

Reviewed-by: Michel Dänzer <[email protected]>

2 files changed, 22 insertions, 6 deletions

diff --git a/src/gallium/drivers/radeonsi/si_descriptors.c b/src/gallium/drivers/radeonsi/si_descriptors.c
index 811c1670f47..3452be3de92 100644
--- a/src/gallium/drivers/radeonsi/si_descriptors.c
+++ b/src/gallium/drivers/radeonsi/si_descriptors.c
@@ -374,6 +374,9 @@ static void si_sampler_views_begin_new_cs(struct si_context *sctx,
 		struct si_sampler_view *rview =
 			(struct si_sampler_view*)views->views[i];
 
+		if (!rview->resource)
+			continue;
+
 		r600_context_bo_reloc(&sctx->b, &sctx->b.rings.gfx,
 				      rview->resource, RADEON_USAGE_READ,
 				      si_get_resource_ro_priority(rview->resource));
@@ -398,9 +401,11 @@ static void si_set_sampler_view(struct si_context *sctx, unsigned shader,
 		struct si_sampler_view *rview =
 			(struct si_sampler_view*)view;
 
-		r600_context_bo_reloc(&sctx->b, &sctx->b.rings.gfx,
-				      rview->resource, RADEON_USAGE_READ,
-				      si_get_resource_ro_priority(rview->resource));
+		if (rview->resource)
+			r600_context_bo_reloc(&sctx->b, &sctx->b.rings.gfx,
+				rview->resource, RADEON_USAGE_READ,
+				si_get_resource_ro_priority(rview->resource));
+
 
 		pipe_sampler_view_reference(&views->views[slot], view);
 		views->desc_data[slot] = view_desc;
@@ -441,7 +446,7 @@ static void si_set_sampler_views(struct pipe_context *ctx,
 
 		si_set_sampler_view(sctx, shader, slot, views[i], rviews[i]->state);
 
-		if (views[i]->texture->target != PIPE_BUFFER) {
+		if (views[i]->texture && views[i]->texture->target != PIPE_BUFFER) {
 			struct r600_texture *rtex =
 				(struct r600_texture*)views[i]->texture;
 
diff --git a/src/gallium/drivers/radeonsi/si_state.c b/src/gallium/drivers/radeonsi/si_state.c
index 85954b74ea1..2deee4516d9 100644
--- a/src/gallium/drivers/radeonsi/si_state.c
+++ b/src/gallium/drivers/radeonsi/si_state.c
@@ -2246,9 +2246,20 @@ static struct pipe_sampler_view *si_create_sampler_view(struct pipe_context *ctx
 	/* initialize base object */
 	view->base = *state;
 	view->base.texture = NULL;
-	pipe_resource_reference(&view->base.texture, texture);
 	view->base.reference.count = 1;
 	view->base.context = ctx;
+
+	/* NULL resource, obey swizzle (only ZERO and ONE make sense). */
+	if (!texture) {
+		view->state[3] = S_008F1C_DST_SEL_X(si_map_swizzle(state->swizzle_r)) |
+				 S_008F1C_DST_SEL_Y(si_map_swizzle(state->swizzle_g)) |
+				 S_008F1C_DST_SEL_Z(si_map_swizzle(state->swizzle_b)) |
+				 S_008F1C_DST_SEL_W(si_map_swizzle(state->swizzle_a)) |
+				 S_008F1C_TYPE(V_008F1C_SQ_RSRC_IMG_1D);
+		return &view->base;
+	}
+
+	pipe_resource_reference(&view->base.texture, texture);
 	view->resource = &tmp->resource;
 
 	/* Buffer resource. */
@@ -2484,7 +2495,7 @@ static void si_sampler_view_destroy(struct pipe_context *ctx,
 {
 	struct si_sampler_view *view = (struct si_sampler_view *)state;
 
-	if (view->resource->b.b.target == PIPE_BUFFER)
+	if (view->resource && view->resource->b.b.target == PIPE_BUFFER)
 		LIST_DELINIT(&view->list);
 
 	pipe_resource_reference(&state->texture, NULL);