r600g: fix alphatest without a colorbuffer on r6xx-r7xx

diff --git a/src/gallium/drivers/r600/r600_state.c b/src/gallium/drivers/r600/r600_state.c
index 269198bf971ff671d847a3d3154759ec71a7ea7b..ab4a3cf574fb9214a509e56fee7b357227a7700f 100644 (file)
--- a/src/gallium/drivers/r600/r600_state.c
+++ b/src/gallium/drivers/r600/r600_state.c
@@ -1595,7 +1595,7 @@ static void r600_set_framebuffer_state(struct pipe_context *ctx,
 {
        struct r600_context *rctx = (struct r600_context *)ctx;
        struct r600_pipe_state *rstate = CALLOC_STRUCT(r600_pipe_state);
-       uint32_t tl, br, shader_control;
+       uint32_t tl, br;
 
        if (rstate == NULL)
                return;
@@ -1618,10 +1618,6 @@ static void r600_set_framebuffer_state(struct pipe_context *ctx,
                r600_db(rctx, rstate, state);
        }
 
-       shader_control = 0;
-       for (int i = 0; i < state->nr_cbufs; i++) {
-               shader_control |= 1 << i;
-       }
        tl = S_028240_TL_X(0) | S_028240_TL_Y(0) | S_028240_WINDOW_OFFSET_DISABLE(1);
        br = S_028244_BR_X(state->width) | S_028244_BR_Y(state->height);
 
@@ -1630,8 +1626,16 @@ static void r600_set_framebuffer_state(struct pipe_context *ctx,
        r600_pipe_state_add_reg(rstate,
                                R_028208_PA_SC_WINDOW_SCISSOR_BR, br);
 
+       /* Always enable the first colorbuffer in CB_SHADER_CONTROL. This
+        * will assure that the alpha-test will work even if there is
+        * no colorbuffer bound. */
        r600_pipe_state_add_reg(rstate, R_0287A0_CB_SHADER_CONTROL,
-                               shader_control);
+                               (1ull << MAX2(state->nr_cbufs, 1)) - 1);
+
+       if (state->nr_cbufs == 0 && rctx->alphatest_state.bypass) {
+               rctx->alphatest_state.bypass = false;
+               r600_atom_dirty(rctx, &rctx->alphatest_state.atom);
+       }
 
        free(rctx->states[R600_PIPE_STATE_FRAMEBUFFER]);
        rctx->states[R600_PIPE_STATE_FRAMEBUFFER] = rstate;