freedreno: Don't count primitives for patches

The gallium helper doesn't like patches and we can't determine how
many primitives it gets tessellated into anyway.  On gens where we
have tessellation, we get the prim count from a HW counter so just
skip counting on the CPU.

Signed-off-by: Kristian H. Kristensen <hoegsberg@google.com>
Acked-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Rob Clark <robdclark@gmail.com>

src/gallium/drivers/freedreno/freedreno_draw.c

@@ -256,7 +256,14 @@ fd_draw_vbo(struct pipe_context *pctx, const struct pipe_draw_info *info)
 
 	batch->num_draws++;
 
-	prims = u_reduced_prims_for_vertices(info->mode, info->count);
+	/* Counting prims in sw doesn't work for GS and tesselation. For older
+	 * gens we don't have those stages and don't have the hw counters enabled,
+	 * so keep the count accurate for non-patch geometry.
+	 */
+	if (info->mode != PIPE_PRIM_PATCHES)
+		prims = u_reduced_prims_for_vertices(info->mode, info->count);
+	else
+		prims = 0;
 
 	ctx->stats.draw_calls++;