radeonsi: add support for compute-only chips

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>

src/amd/common/ac_gpu_info.c

@@ -436,6 +436,7 @@ bool ac_query_gpu_info(int fd, void *dev_p,
 	assert(util_is_power_of_two_or_zero(dma.available_rings + 1));
 	assert(util_is_power_of_two_or_zero(compute.available_rings + 1));
 
+	info->has_graphics = gfx.available_rings > 0;
 	info->num_sdma_rings = util_bitcount(dma.available_rings);
 	info->num_compute_rings = util_bitcount(compute.available_rings);
 

src/amd/common/ac_gpu_info.h

@@ -53,6 +53,7 @@ struct radeon_info {
 	enum chip_class             chip_class;
 	uint32_t                    family_id;
 	uint32_t                    chip_external_rev;
+	bool                        has_graphics; /* false if the chip is compute-only */
 	uint32_t                    num_compute_rings;
 	uint32_t                    num_sdma_rings;
 	uint32_t                    clock_crystal_freq;

src/amd/common/ac_surface.c

@@ -658,6 +658,7 @@ static int gfx6_compute_surface(ADDR_HANDLE addrlib,
 	 */
 	AddrSurfInfoIn.flags.dccCompatible =
 		info->chip_class >= GFX8 &&
+		info->has_graphics && /* disable DCC on compute-only chips */
 		!(surf->flags & RADEON_SURF_Z_OR_SBUFFER) &&
 		!(surf->flags & RADEON_SURF_DISABLE_DCC) &&
 		!compressed &&
@@ -1122,7 +1123,9 @@ static int gfx9_compute_miptree(ADDR_HANDLE addrlib,
 		}
 
 		/* DCC */
-		if (!(surf->flags & RADEON_SURF_DISABLE_DCC) && !compressed &&
+		if (info->has_graphics &&
+		    !(surf->flags & RADEON_SURF_DISABLE_DCC) &&
+		    !compressed &&
 		    gfx9_is_dcc_capable(info, in->swizzleMode)) {
 			ADDR2_COMPUTE_DCCINFO_INPUT din = {0};
 			ADDR2_COMPUTE_DCCINFO_OUTPUT dout = {0};

src/gallium/drivers/radeonsi/si_get.c

@@ -157,7 +157,7 @@ static int si_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
 	case PIPE_CAP_COMPUTE_GRID_INFO_LAST_BLOCK:
 	case PIPE_CAP_IMAGE_LOAD_FORMATTED:
 	case PIPE_CAP_PREFER_COMPUTE_BLIT_FOR_MULTIMEDIA:
-        case PIPE_CAP_TGSI_DIV:
+	case PIPE_CAP_TGSI_DIV:
 		return 1;
 
 	case PIPE_CAP_QUERY_SO_OVERFLOW:
@@ -166,6 +166,9 @@ static int si_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
 	case PIPE_CAP_POST_DEPTH_COVERAGE:
 		return sscreen->info.chip_class >= GFX10;
 
+	case PIPE_CAP_GRAPHICS:
+		return sscreen->info.has_graphics;
+
 	case PIPE_CAP_RESOURCE_FROM_USER_MEMORY:
 		return !SI_BIG_ENDIAN && sscreen->info.has_userptr;
 

src/gallium/drivers/radeonsi/si_pipe.c

@@ -392,8 +392,14 @@ static void si_set_context_param(struct pipe_context *ctx,
 static struct pipe_context *si_create_context(struct pipe_screen *screen,
                                               unsigned flags)
 {
-	struct si_context *sctx = CALLOC_STRUCT(si_context);
 	struct si_screen* sscreen = (struct si_screen *)screen;
+
+	/* Don't create a context if it's not compute-only and hw is compute-only. */
+	if (!sscreen->info.has_graphics &&
+	    !(flags & PIPE_CONTEXT_COMPUTE_ONLY))
+		return NULL;
+
+	struct si_context *sctx = CALLOC_STRUCT(si_context);
 	struct radeon_winsys *ws = sscreen->ws;
 	int shader, i;
 	bool stop_exec_on_failure = (flags & PIPE_CONTEXT_LOSE_CONTEXT_ON_RESET) != 0;
@@ -520,10 +526,10 @@ static struct pipe_context *si_create_context(struct pipe_screen *screen,
 	si_init_fence_functions(sctx);
 	si_init_query_functions(sctx);
 	si_init_state_compute_functions(sctx);
+	si_init_context_texture_functions(sctx);
 
 	/* Initialize graphics-only context functions. */
 	if (sctx->has_graphics) {
-		si_init_context_texture_functions(sctx);
 		if (sctx->chip_class >= GFX10)
 			gfx10_init_query(sctx);
 		si_init_msaa_functions(sctx);
@@ -1251,8 +1257,9 @@ radeonsi_screen_create_impl(struct radeon_winsys *ws,
 	}
 
 	/* Create the auxiliary context. This must be done last. */
-	sscreen->aux_context = si_create_context(
-		&sscreen->b, sscreen->options.aux_debug ? PIPE_CONTEXT_DEBUG : 0);
+	sscreen->aux_context = si_create_context(&sscreen->b,
+		(sscreen->options.aux_debug ? PIPE_CONTEXT_DEBUG : 0) |
+		(sscreen->info.has_graphics ? 0 : PIPE_CONTEXT_COMPUTE_ONLY));
 	if (sscreen->options.aux_debug) {
 		struct u_log_context *log = CALLOC_STRUCT(u_log_context);
 		u_log_context_init(log);

src/gallium/winsys/radeon/drm/radeon_drm_winsys.c

@@ -587,6 +587,7 @@ static bool do_winsys_init(struct radeon_drm_winsys *ws)
     ws->info.has_2d_tiling = ws->info.chip_class <= GFX6 || ws->info.drm_minor >= 35;
     ws->info.has_read_registers_query = ws->info.drm_minor >= 42;
     ws->info.max_alignment = 1024*1024;
+    ws->info.has_graphics = true;
 
     ws->check_vm = strstr(debug_get_option("R600_DEBUG", ""), "check_vm") != NULL;