dri/nv10: Use fast Z clears.

src/mesa/drivers/dri/nouveau/nouveau_class.h

@@ -3191,6 +3191,12 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #define  NV17TCL_DMA_IN_MEMORY4								0x000001ac
 #define  NV17TCL_DMA_IN_MEMORY5								0x000001b0
 #define  NV17TCL_COLOR_MASK_ENABLE							0x000002bc
+#define  NV17TCL_ZCLEAR_ENABLE								0x000003f8
+#define  NV17TCL_ZCLEAR_VALUE								0x000003fc
+#define   NV17TCL_ZCLEAR_VALUE_DEPTH_SHIFT						8
+#define   NV17TCL_ZCLEAR_VALUE_DEPTH_MASK						0xffffff00
+#define   NV17TCL_ZCLEAR_VALUE_SEQUENCE_SHIFT						0
+#define   NV17TCL_ZCLEAR_VALUE_SEQUENCE_MASK						0x000000ff
 #define  NV17TCL_LMA_DEPTH_BUFFER_PITCH							0x00000d5c
 #define  NV17TCL_LMA_DEPTH_BUFFER_OFFSET						0x00000d60
 #define  NV17TCL_LMA_DEPTH_FILL_VALUE							0x00000d68

src/mesa/drivers/dri/nouveau/nouveau_context.h

@@ -67,6 +67,11 @@ struct nouveau_context {
 	struct nouveau_hw_state hw;
 	struct nouveau_bo_state bo;
 	struct nouveau_render_state render;
+
+	struct {
+		GLboolean clear_blocked;
+		int clear_seq;
+	} hierz;
 };
 
 #define to_nouveau_context(ctx)	((struct nouveau_context *)(ctx))

src/mesa/drivers/dri/nouveau/nouveau_fbo.h

@@ -29,8 +29,12 @@
 
 struct nouveau_framebuffer {
 	struct gl_framebuffer base;
-	struct nouveau_bo *lma_bo;
 	GLboolean need_front;
+
+	struct {
+		struct nouveau_bo *bo;
+		uint32_t clear_value;
+	} hierz;
 };
 #define to_nouveau_framebuffer(x) ((struct nouveau_framebuffer *)(x))
 

src/mesa/drivers/dri/nouveau/nv10_context.c

@@ -40,9 +40,31 @@ static const struct dri_extension nv10_extensions[] = {
 	{ NULL,				NULL }
 };
 
+static GLboolean
+use_fast_zclear(GLcontext *ctx, GLbitfield buffers)
+{
+	struct nouveau_context *nctx = to_nouveau_context(ctx);
+	struct gl_framebuffer *fb = ctx->DrawBuffer;
+
+	if (buffers & BUFFER_BIT_STENCIL) {
+		/*
+		 * The stencil test is bypassed when fast Z clears are
+		 * enabled.
+		 */
+		nctx->hierz.clear_blocked = GL_TRUE;
+		context_dirty(ctx, ZCLEAR);
+		return GL_FALSE;
+	}
+
+	return !nctx->hierz.clear_blocked &&
+		fb->_Xmax == fb->Width && fb->_Xmin == 0 &&
+		fb->_Ymax == fb->Height && fb->_Ymin == 0;
+}
+
 static void
 nv10_clear(GLcontext *ctx, GLbitfield buffers)
 {
+	struct nouveau_context *nctx = to_nouveau_context(ctx);
 	struct nouveau_channel *chan = context_chan(ctx);
 	struct nouveau_grobj *celsius = context_eng3d(ctx);
 	struct nouveau_framebuffer *nfb = to_nouveau_framebuffer(
@@ -50,16 +72,28 @@ nv10_clear(GLcontext *ctx, GLbitfield buffers)
 
 	nouveau_validate_framebuffer(ctx);
 
-	/* Clear the LMA depth buffer, if present. */
-	if ((buffers & BUFFER_BIT_DEPTH) && ctx->Depth.Mask &&
-	    nfb->lma_bo) {
+	if ((buffers & BUFFER_BIT_DEPTH) &&
+	    ctx->Depth.Mask && nfb->hierz.bo) {
 		struct nouveau_surface *s = &to_nouveau_renderbuffer(
 			nfb->base._DepthBuffer->Wrapped)->surface;
 
+		/* Clear the hierarchical depth buffer */
 		BEGIN_RING(chan, celsius, NV17TCL_LMA_DEPTH_FILL_VALUE, 1);
 		OUT_RING(chan, pack_zs_f(s->format, ctx->Depth.Clear, 0));
 		BEGIN_RING(chan, celsius, NV17TCL_LMA_DEPTH_BUFFER_CLEAR, 1);
 		OUT_RING(chan, 1);
+
+		/* Mark the depth buffer as cleared */
+		if (use_fast_zclear(ctx, buffers)) {
+			if (nctx->hierz.clear_seq)
+				buffers &= ~BUFFER_BIT_DEPTH;
+
+			nfb->hierz.clear_value =
+				pack_zs_f(s->format, ctx->Depth.Clear, 0);
+			nctx->hierz.clear_seq++;
+
+			context_dirty(ctx, ZCLEAR);
+		}
 	}
 
 	nouveau_clear(ctx, buffers);
@@ -423,7 +457,8 @@ const struct nouveau_driver nv10_driver = {
 		nv10_emit_tex_obj,
 		nouveau_emit_nothing,
 		nouveau_emit_nothing,
-		nv10_emit_viewport
+		nv10_emit_viewport,
+		nv10_emit_zclear
 	},
-	.num_emit = NUM_NOUVEAU_STATE,
+	.num_emit = NUM_NV10_STATE,
 };

src/mesa/drivers/dri/nouveau/nv10_driver.h

@@ -27,6 +27,11 @@
 #ifndef __NV10_DRIVER_H__
 #define __NV10_DRIVER_H__
 
+enum {
+	NOUVEAU_STATE_ZCLEAR = NUM_NOUVEAU_STATE,
+	NUM_NV10_STATE
+};
+
 #define NV10_TEXTURE_UNITS 2
 
 /* nv10_context.c */
@@ -52,6 +57,9 @@ nv10_emit_scissor(GLcontext *ctx, int emit);
 void
 nv10_emit_viewport(GLcontext *ctx, int emit);
 
+void
+nv10_emit_zclear(GLcontext *ctx, int emit);
+
 /* nv10_state_polygon.c */
 void
 nv10_emit_cull_face(GLcontext *ctx, int emit);

src/mesa/drivers/dri/nouveau/nv10_state_fb.c

@@ -62,14 +62,14 @@ setup_lma_buffer(GLcontext *ctx)
 		height = align(fb->Height, 2),
 		size = pitch * height;
 
-	if (!nfb->lma_bo || nfb->lma_bo->size != size) {
-		nouveau_bo_ref(NULL, &nfb->lma_bo);
+	if (!nfb->hierz.bo || nfb->hierz.bo->size != size) {
+		nouveau_bo_ref(NULL, &nfb->hierz.bo);
 		nouveau_bo_new(context_dev(ctx), NOUVEAU_BO_VRAM, 0, size,
-			       &nfb->lma_bo);
+			       &nfb->hierz.bo);
 	}
 
 	nouveau_bo_markl(bctx, celsius, NV17TCL_LMA_DEPTH_BUFFER_OFFSET,
-			 nfb->lma_bo, 0, NOUVEAU_BO_VRAM | NOUVEAU_BO_RDWR);
+			 nfb->hierz.bo, 0, NOUVEAU_BO_VRAM | NOUVEAU_BO_RDWR);
 
 	WAIT_RING(chan, 9);
 	BEGIN_RING(chan, celsius, NV17TCL_LMA_DEPTH_WINDOW_X, 4);
@@ -134,8 +134,10 @@ nv10_emit_framebuffer(GLcontext *ctx, int emit)
 		nouveau_bo_markl(bctx, celsius, NV10TCL_ZETA_OFFSET,
 				 s->bo, 0, bo_flags);
 
-		if (context_chipset(ctx) >= 0x17)
+		if (context_chipset(ctx) >= 0x17) {
 			setup_lma_buffer(ctx);
+			context_dirty(ctx, ZCLEAR);
+		}
 	}
 
 	BEGIN_RING(chan, celsius, NV10TCL_RT_FORMAT, 2);
@@ -187,3 +189,20 @@ nv10_emit_viewport(GLcontext *ctx, int emit)
 
 	context_dirty(ctx, PROJECTION);
 }
+
+void
+nv10_emit_zclear(GLcontext *ctx, int emit)
+{
+	struct nouveau_context *nctx = to_nouveau_context(ctx);
+	struct nouveau_channel *chan = context_chan(ctx);
+	struct nouveau_grobj *celsius = context_eng3d(ctx);
+	struct nouveau_framebuffer *nfb =
+		to_nouveau_framebuffer(ctx->DrawBuffer);
+
+	if (nfb->hierz.bo) {
+		BEGIN_RING(chan, celsius, NV17TCL_ZCLEAR_ENABLE, 2);
+		OUT_RING(chan, nctx->hierz.clear_blocked ? 0 : 1);
+		OUT_RING(chan, nfb->hierz.clear_value |
+			 (nctx->hierz.clear_seq & 0xff));
+	}
+}