r300g: fix occlusion queries when depth test is disabled or zbuffer is missing

From now on, depth test is always enabled in hardware.

If depth test is disabled in Gallium, the hardware Z function is set to ALWAYS.

If there is no zbuffer set, the colorbuffer0 memory is set as a zbuffer
to silence the CS checker.

This fixes piglit:
- occlusion-query-discard
- NV_conditional_render/bitmap
- NV_conditional_render/drawpixels
- NV_conditional_render/vertex_array

diff --git a/src/gallium/drivers/r300/r300_emit.c b/src/gallium/drivers/r300/r300_emit.c
index 874037ed9fd5eb0f060b50f48b2b3833a49e9d18..5d6188e5120e0a678aebaf85d6df159bcebf5623 100644 (file)
--- a/src/gallium/drivers/r300/r300_emit.c
+++ b/src/gallium/drivers/r300/r300_emit.c
@@ -439,6 +439,19 @@ void r300_emit_fb_state(struct r300_context* r300, unsigned size, void* state)
             OUT_CS_REG(R300_ZB_ZMASK_OFFSET, 0);
             OUT_CS_REG(R300_ZB_ZMASK_PITCH, surf->pitch_zmask);
         }
+    /* Set up a dummy zbuffer. Otherwise occlusion queries won't work.
+     * Use the first colorbuffer, we will disable writes in the DSA state
+     * so as not to corrupt it. */
+    } else if (fb->nr_cbufs) {
+        surf = r300_surface(fb->cbufs[0]);
+
+        OUT_CS_REG(R300_ZB_FORMAT, R300_DEPTHFORMAT_16BIT_INT_Z);
+
+        OUT_CS_REG(R300_ZB_DEPTHOFFSET, 0);
+        OUT_CS_RELOC(surf);
+
+        OUT_CS_REG(R300_ZB_DEPTHPITCH, 4 | R300_DEPTHMICROTILE_TILED);
+        OUT_CS_RELOC(surf);
     }
 
     END_CS;

diff --git a/src/gallium/drivers/r300/r300_state.c b/src/gallium/drivers/r300/r300_state.c
index bc6c67dd0345e7e1204f562d99f64aa544092f9b..84d9da3ad9d408df0198922c0989a4c7fd0b02bd 100644 (file)
--- a/src/gallium/drivers/r300/r300_state.c
+++ b/src/gallium/drivers/r300/r300_state.c
@@ -549,6 +549,10 @@ static void*
         dsa->z_stencil_control |=
             (r300_translate_depth_stencil_function(state->depth.func) <<
                 R300_Z_FUNC_SHIFT);
+    } else {
+        /* We must enable depth test, otherwise occlusion queries won't work. */
+        dsa->z_buffer_control |= R300_Z_ENABLE;
+        dsa->z_stencil_control |= R300_ZS_ALWAYS;
     }
 
     /* Stencil buffer setup. */
@@ -632,11 +636,13 @@ static void*
     OUT_CB_REG(R500_FG_ALPHA_VALUE, dsa->alpha_value);
     END_CB;
 
+    /* We must enable depth test, otherwise occlusion queries won't work.
+     * We setup a dummy zbuffer to silent the CS checker, see emit_fb_state. */
     BEGIN_CB(dsa->cb_zb_no_readwrite, 10);
     OUT_CB_REG(R300_FG_ALPHA_FUNC, dsa->alpha_function);
     OUT_CB_REG_SEQ(R300_ZB_CNTL, 3);
-    OUT_CB(0);
-    OUT_CB(0);
+    OUT_CB(R300_Z_ENABLE);
+    OUT_CB(R300_ZS_ALWAYS);
     OUT_CB(0);
     OUT_CB_REG(R500_ZB_STENCILREFMASK_BF, 0);
     OUT_CB_REG(R500_FG_ALPHA_VALUE, dsa->alpha_value);
@@ -645,8 +651,8 @@ static void*
     BEGIN_CB(dsa->cb_fp16_zb_no_readwrite, 10);
     OUT_CB_REG(R300_FG_ALPHA_FUNC, dsa->alpha_function_fp16);
     OUT_CB_REG_SEQ(R300_ZB_CNTL, 3);
-    OUT_CB(0);
-    OUT_CB(0);
+    OUT_CB(R300_Z_ENABLE);
+    OUT_CB(R300_ZS_ALWAYS);
     OUT_CB(0);
     OUT_CB_REG(R500_ZB_STENCILREFMASK_BF, 0);
     OUT_CB_REG(R500_FG_ALPHA_VALUE, dsa->alpha_value);
@@ -792,12 +798,14 @@ void r300_mark_fb_state_dirty(struct r300_context *r300,
     /* Now compute the fb_state atom size. */
     r300->fb_state.size = 2 + (8 * state->nr_cbufs);
 
-    if (r300->cbzb_clear)
+    if (r300->cbzb_clear) {
         r300->fb_state.size += 10;
-    else if (state->zsbuf) {
+    } else if (state->zsbuf) {
         r300->fb_state.size += 10;
         if (r300->hyperz_enabled)
             r300->fb_state.size += 8;
+    } else if (state->nr_cbufs) {
+        r300->fb_state.size += 10;
     }
 
     /* The size of the rest of atoms stays the same. */