diff --git a/ubb-patgen/Makefile b/ubb-patgen/Makefile
index 5bb248e..eafa139 100644
--- a/ubb-patgen/Makefile
+++ b/ubb-patgen/Makefile
@@ -11,7 +11,7 @@
 #
 
 CC = mipsel-openwrt-linux-gcc
-CFLAGS = -g -Wall -O9 -I../libubb/include
+CFLAGS = -g -Wall -O9 -march=mips32 -I../libubb/include
 LDFLAGS =
 LDLIBS = -L../libubb -lubb -lm
 
diff --git a/ubb-patgen/ubb-patgen.c b/ubb-patgen/ubb-patgen.c
index dd90df1..8f54852 100644
--- a/ubb-patgen/ubb-patgen.c
+++ b/ubb-patgen/ubb-patgen.c
@@ -18,6 +18,7 @@
 #include <math.h>
 #include <time.h>
 #include <assert.h>
+#include <asm/cachectl.h>
 
 #include <ubb/ubb.h>
 #include <ubb/regs4740.h>
@@ -25,9 +26,13 @@
 #include <ubb/physmem.h>
 
 
+#define	USE_DMA
 #define	DMA	5
 
 
+extern int cacheflush(char *addr, int nbytes, int cache);
+
+
 /* ----- List available bus clock frequencies ------------------------------ */
 
 
@@ -309,6 +314,13 @@ static void send_buffer(const struct mmcclk *clk,
 #ifdef USE_DMA
 	unsigned long phys;
 
+	if (cacheflush((void *) buf, nibbles >> 1, DCACHE)) {
+		perror("cacheflush");
+		exit(1);
+	}
+
+	asm("sync");	/* flush the write buffer */
+
 	phys = physmem_xlat((void *) buf);
 	mmc_buffer(clk, buf[0] >> 4, phys, nibbles, mask);
 #else