freedreno: fix segfault when no color buffer bound

Don't crash when no color buffer bound.  Something caught when starting
to run piglit, fixes a hanful of piglit tests.

Signed-off-by: Rob Clark <robclark@freedesktop.org>

src/gallium/drivers/freedreno/a2xx/fd2_gmem.c

@@ -337,7 +337,7 @@ fd2_emit_tile_init(struct fd_context *ctx)
 	struct fd_ringbuffer *ring = ctx->ring;
 	struct pipe_framebuffer_state *pfb = &ctx->framebuffer;
 	struct fd_gmem_stateobj *gmem = &ctx->gmem;
-	enum pipe_format format = pfb->cbufs[0]->format;
+	enum pipe_format format = pipe_surface_format(pfb->cbufs[0]);
 	uint32_t reg;
 
 	OUT_PKT3(ring, CP_SET_CONSTANT, 4);
@@ -358,7 +358,7 @@ fd2_emit_tile_prep(struct fd_context *ctx, uint32_t xoff, uint32_t yoff,
 {
 	struct fd_ringbuffer *ring = ctx->ring;
 	struct pipe_framebuffer_state *pfb = &ctx->framebuffer;
-	enum pipe_format format = pfb->cbufs[0]->format;
+	enum pipe_format format = pipe_surface_format(pfb->cbufs[0]);
 
 	OUT_PKT3(ring, CP_SET_CONSTANT, 2);
 	OUT_RING(ring, CP_REG(REG_A2XX_RB_COLOR_INFO));
@@ -379,7 +379,7 @@ fd2_emit_tile_renderprep(struct fd_context *ctx, uint32_t xoff, uint32_t yoff,
 {
 	struct fd_ringbuffer *ring = ctx->ring;
 	struct pipe_framebuffer_state *pfb = &ctx->framebuffer;
-	enum pipe_format format = pfb->cbufs[0]->format;
+	enum pipe_format format = pipe_surface_format(pfb->cbufs[0]);
 
 	OUT_PKT3(ring, CP_SET_CONSTANT, 2);
 	OUT_RING(ring, CP_REG(REG_A2XX_RB_COLOR_INFO));

src/gallium/drivers/freedreno/a3xx/fd3_gmem.c

@@ -214,8 +214,12 @@ fd3_emit_tile_gmem2mem(struct fd_context *ctx, uint32_t xoff, uint32_t yoff,
 		}, 1);
 
 	if (ctx->resolve & (FD_BUFFER_DEPTH | FD_BUFFER_STENCIL)) {
-		uint32_t base = depth_base(&ctx->gmem) *
-				fd_resource(pfb->cbufs[0]->texture)->cpp;
+		uint32_t base = 0;
+		if (pfb->cbufs[0]) {
+			struct fd_resource *rsc =
+					fd_resource(pfb->cbufs[0]->texture);
+			base = depth_base(&ctx->gmem) * rsc->cpp;
+		}
 		emit_gmem2mem_surf(ring, RB_COPY_DEPTH_STENCIL, base, pfb->zsbuf);
 	}
 
@@ -410,8 +414,11 @@ static void
 fd3_emit_sysmem_prep(struct fd_context *ctx)
 {
 	struct pipe_framebuffer_state *pfb = &ctx->framebuffer;
-	struct fd_resource *rsc = fd_resource(pfb->cbufs[0]->texture);
 	struct fd_ringbuffer *ring = ctx->ring;
+	uint32_t pitch = 0;
+
+	if (pfb->cbufs[0])
+		pitch = fd_resource(pfb->cbufs[0]->texture)->pitch;
 
 	fd3_emit_restore(ctx);
 
@@ -422,7 +429,7 @@ fd3_emit_sysmem_prep(struct fd_context *ctx)
 	emit_mrt(ring, pfb->nr_cbufs, pfb->cbufs, NULL, 0);
 
 	fd3_emit_rbrc_tile_state(ring,
-			A3XX_RB_RENDER_CONTROL_BIN_WIDTH(rsc->pitch));
+			A3XX_RB_RENDER_CONTROL_BIN_WIDTH(pitch));
 
 	/* setup scissor/offset for current tile: */
 	OUT_PKT0(ring, REG_A3XX_PA_SC_WINDOW_OFFSET, 1);

src/gallium/drivers/freedreno/freedreno_context.c

@@ -86,7 +86,8 @@ fd_context_render(struct pipe_context *pctx)
 	ctx->gmem_reason = 0;
 	ctx->num_draws = 0;
 
-	fd_resource(pfb->cbufs[0]->texture)->dirty = false;
+	if (pfb->cbufs[0])
+		fd_resource(pfb->cbufs[0]->texture)->dirty = false;
 	if (pfb->zsbuf)
 		fd_resource(pfb->zsbuf->texture)->dirty = false;
 }

src/gallium/drivers/freedreno/freedreno_draw.c

@@ -193,8 +193,8 @@ fd_clear(struct pipe_context *pctx, unsigned buffers,
 	}
 
 	DBG("%x depth=%f, stencil=%u (%s/%s)", buffers, depth, stencil,
-			util_format_name(pfb->cbufs[0]->format),
-			pfb->zsbuf ? util_format_name(pfb->zsbuf->format) : "none");
+		util_format_short_name(pipe_surface_format(pfb->cbufs[0])),
+		util_format_short_name(pipe_surface_format(pfb->zsbuf)));
 
 	ctx->clear(ctx, buffers, color, depth, stencil);
 

src/gallium/drivers/freedreno/freedreno_gmem.c

@@ -72,12 +72,15 @@ calculate_tiles(struct fd_context *ctx)
 	struct fd_gmem_stateobj *gmem = &ctx->gmem;
 	struct pipe_scissor_state *scissor = &ctx->max_scissor;
 	struct pipe_framebuffer_state *pfb = &ctx->framebuffer;
-	uint32_t cpp = util_format_get_blocksize(pfb->cbufs[0]->format);
 	uint32_t gmem_size = ctx->screen->gmemsize_bytes;
 	uint32_t minx, miny, width, height;
 	uint32_t nbins_x = 1, nbins_y = 1;
 	uint32_t bin_w, bin_h;
 	uint32_t max_width = 992;
+	uint32_t cpp = 4;
+
+	if (pfb->cbufs[0])
+		cpp = util_format_get_blocksize(pfb->cbufs[0]->format);
 
 	if ((gmem->cpp == cpp) &&
 			!memcmp(&gmem->scissor, scissor, sizeof(gmem->scissor))) {
@@ -211,15 +214,15 @@ fd_gmem_render_tiles(struct pipe_context *pctx)
 
 	if (sysmem) {
 		DBG("rendering sysmem (%s/%s)",
-			util_format_name(pfb->cbufs[0]->format),
-			pfb->zsbuf ? util_format_name(pfb->zsbuf->format) : "none");
+			util_format_short_name(pipe_surface_format(pfb->cbufs[0])),
+			util_format_short_name(pipe_surface_format(pfb->zsbuf)));
 		render_sysmem(ctx);
 	} else {
 		struct fd_gmem_stateobj *gmem = &ctx->gmem;
-		DBG("rendering %dx%d tiles (%s/%s)", gmem->nbins_x, gmem->nbins_y,
-			util_format_name(pfb->cbufs[0]->format),
-			pfb->zsbuf ? util_format_name(pfb->zsbuf->format) : "none");
 		calculate_tiles(ctx);
+		DBG("rendering %dx%d tiles (%s/%s)", gmem->nbins_x, gmem->nbins_y,
+			util_format_short_name(pipe_surface_format(pfb->cbufs[0])),
+			util_format_short_name(pipe_surface_format(pfb->zsbuf)));
 		render_tiles(ctx);
 	}
 
@@ -231,7 +234,8 @@ fd_gmem_render_tiles(struct pipe_context *pctx)
 
 	/* update timestamps on render targets: */
 	timestamp = fd_ringbuffer_timestamp(ctx->ring);
-	fd_resource(pfb->cbufs[0]->texture)->timestamp = timestamp;
+	if (pfb->cbufs[0])
+		fd_resource(pfb->cbufs[0]->texture)->timestamp = timestamp;
 	if (pfb->zsbuf)
 		fd_resource(pfb->zsbuf->texture)->timestamp = timestamp;
 

src/gallium/drivers/freedreno/freedreno_state.c

@@ -120,7 +120,7 @@ fd_set_framebuffer_state(struct pipe_context *pctx,
 	unsigned i;
 
 	DBG("%d: cbufs[0]=%p, zsbuf=%p", ctx->needs_flush,
-			cso->cbufs[0], cso->zsbuf);
+			framebuffer->cbufs[0], framebuffer->zsbuf);
 
 	fd_context_render(pctx);
 

src/gallium/drivers/freedreno/freedreno_util.h

@@ -33,6 +33,7 @@
 #include <freedreno_ringbuffer.h>
 
 #include "pipe/p_format.h"
+#include "pipe/p_state.h"
 #include "util/u_debug.h"
 #include "util/u_math.h"
 #include "util/u_half.h"
@@ -79,6 +80,15 @@ static inline uint32_t DRAW(enum pc_di_primtype prim_type,
 			(1                 << 14);
 }
 
+
+static inline enum pipe_format
+pipe_surface_format(struct pipe_surface *psurf)
+{
+	if (!psurf)
+		return PIPE_FORMAT_NONE;
+	return psurf->format;
+}
+
 #define LOG_DWORDS 0