Add defines for the values written to R300_RB3D_ZCACHE_CTLSTAT.

Note that just like the values written to R300_RB3D_DSTCACHE_CTLSTAT these
values are really unknown; ideally more reverse engineering should be done to
determine what these values mean and when they should be set.

src/mesa/drivers/dri/r300/r300_ioctl.c

@@ -166,7 +166,7 @@ static void r300ClearBuffer(r300ContextPtr r300, int flags, int buffer)
 	  
 
 	reg_start(R300_RB3D_ZCACHE_CTLSTAT,0);
-	e32(0x00000003);
+	e32(R300_RB3D_ZCACHE_CTLSTAT_03);
 	cp_wait(rmesa, R300_WAIT_3D | R300_WAIT_3D_CLEAN);
 }
 

src/mesa/drivers/dri/r300/r300_reg.h

@@ -1397,6 +1397,8 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 /* gap */
 
 #define R300_RB3D_ZCACHE_CTLSTAT            0x4F18 /* GUESS */
+#       define R300_RB3D_ZCACHE_CTLSTAT_01  0x1
+#       define R300_RB3D_ZCACHE_CTLSTAT_03  0x3
 
 /* gap */
 

src/mesa/drivers/dri/r300/r300_render.c

@@ -347,7 +347,7 @@ GLboolean r300_run_vb_render(GLcontext *ctx,
 	e32(R300_RB3D_DSTCACHE_0A);
 
 	reg_start(R300_RB3D_ZCACHE_CTLSTAT,0);
-	e32(0x00000003);
+	e32(R300_RB3D_ZCACHE_CTLSTAT_03);
 	
 	r300EmitState(rmesa);
 	
@@ -363,7 +363,7 @@ GLboolean r300_run_vb_render(GLcontext *ctx,
 	e32(R300_RB3D_DSTCACHE_0A /*R300_RB3D_DSTCACHE_02*/);
 
 	reg_start(R300_RB3D_ZCACHE_CTLSTAT,0);
-	e32(0x00000003/*0x1*/);
+	e32(R300_RB3D_ZCACHE_CTLSTAT_03 /*R300_RB3D_ZCACHE_CTLSTAT_01*/);
 
 #ifdef USER_BUFFERS
 	r300UseArrays(ctx);