diff --git a/cmd/memtester/memtester.c b/cmd/memtester/memtester.c
index 8f624edbd2..7936c03303 100644
--- a/cmd/memtester/memtester.c
+++ b/cmd/memtester/memtester.c
@@ -61,7 +61,8 @@ off_t physaddrbase;
  * err_exit: 1: exit test when found fail.
  * return 0: success, other: fail
  */
-int doing_memtester(ul *arg, ul testenable, ul loops, ul err_exit)
+int doing_memtester(ul *arg, ul testenable, ul loops, ul err_exit,
+		    ul fix_bit, ul fix_level)
 {
 	ul loop, i, j;
 	ul start_adr[CONFIG_NR_DRAM_BANKS], length[CONFIG_NR_DRAM_BANKS];
@@ -115,7 +116,8 @@ int doing_memtester(ul *arg, ul testenable, ul loops, ul err_exit)
 				if (testenable && (!((1 << i) & testenable)))
 					continue;
 				printf("  %-20s: ", tests[i].name);
-				if (!tests[i].fp(bufa[j], bufb[j], count[j])) {
+				if (!tests[i].fp(bufa[j], bufb[j], count[j],
+						 fix_bit, fix_level)) {
 					printf("ok\n");
 				} else {
 					exit_code |= EXIT_FAIL_OTHERTEST;
@@ -157,6 +159,8 @@ static int do_memtester(cmd_tbl_t *cmdtp, int flag, int argc,
 	ul loops = 0;
 	ul testenable = 0;
 	ul err_exit = 0;
+	ul fix_bit = 0;
+	ul fix_level = 0;
 
 	printf("memtester version " __version__ " (%d-bit)\n", UL_LEN);
 	printf("Copyright (C) 2001-2012 Charles Cazabon.\n");
@@ -184,18 +188,26 @@ static int do_memtester(cmd_tbl_t *cmdtp, int flag, int argc,
 			return CMD_RET_USAGE;
 
 	if (argc > 5)
-		if (strict_strtoul(argv[5], 0, &loops) < 0)
+		if (strict_strtoul(argv[5], 0, &fix_bit) < 0)
 			return CMD_RET_USAGE;
 
-	doing_memtester(arg, testenable, loops, err_exit);
+	if (argc > 6)
+		if (strict_strtoul(argv[6], 0, &fix_level) < 0)
+			return CMD_RET_USAGE;
+
+	if (argc > 7)
+		if (strict_strtoul(argv[7], 0, &loops) < 0)
+			return CMD_RET_USAGE;
+
+	doing_memtester(arg, testenable, loops, err_exit, fix_bit, fix_level);
 
 	printf("Done.\n");
 	return 0;
 }
 
-U_BOOT_CMD(memtester, 6, 1, do_memtester,
+U_BOOT_CMD(memtester, 8, 1, do_memtester,
 	   "do memtester",
-	   "[start length [testenable err_exit [loop]]]\n"
+	   "[start length [testenable err_exit fix_bit fix_level [loop]]]\n"
 	   "start: start address, should be 4k align\n"
 	   "length: test length, should be 4k align, if 0 testing full space\n"
 	   "testenable[option]: enable pattern by set bit to 1, null or 0"
@@ -220,6 +232,8 @@ U_BOOT_CMD(memtester, 6, 1, do_memtester,
 	   "	bit17: test stuck address\n"
 	   "	example: testenable=0x1000,enable Bit Flip only\n"
 	   "err_exit: if 1 stop testing immediately when finding error\n"
+	   "fix_bit: fixed bit to a exact level\n"
+	   "fix_level: fix_bit's level, 0: low, 1: high\n"
 	   "loop[option]: testing loop, if 0 or null endless loop\n"
 	   "example:\n"
 	   "	memtester 0x200000 0x1000000: start address: 0x200000 length:"
diff --git a/cmd/memtester/memtester.h b/cmd/memtester/memtester.h
index 779a1ece41..5275a8cf82 100644
--- a/cmd/memtester/memtester.h
+++ b/cmd/memtester/memtester.h
@@ -23,5 +23,6 @@ extern int use_phys;
 extern off_t physaddrbase;
 
 int doing_memtester(unsigned long *arg, unsigned long testenable,
-		    unsigned long loops, unsigned long err_exit);
+		    unsigned long loops, unsigned long err_exit,
+		    unsigned long fix_bit, unsigned long fix_level);
 #endif /* _CMD_MEMTESTER_H */
diff --git a/cmd/memtester/tests.c b/cmd/memtester/tests.c
index f50db4c19e..4f27c1c4cd 100644
--- a/cmd/memtester/tests.c
+++ b/cmd/memtester/tests.c
@@ -114,7 +114,8 @@ int test_stuck_address(u32v *bufa, size_t count)
 	return 0;
 }
 
-int test_random_value(u32v *bufa, u32v *bufb, size_t count)
+int test_random_value(u32v *bufa, u32v *bufb, size_t count,
+		      ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -136,7 +137,9 @@ int test_random_value(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_xor_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_xor_comparison(u32v *bufa, u32v *bufb, size_t count,
+			ul fix_bit, ul fix_level)
+
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -150,7 +153,8 @@ int test_xor_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_sub_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_sub_comparison(u32v *bufa, u32v *bufb, size_t count,
+			ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -164,7 +168,8 @@ int test_sub_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_mul_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_mul_comparison(u32v *bufa, u32v *bufb, size_t count,
+			ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -178,7 +183,8 @@ int test_mul_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_div_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_div_comparison(u32v *bufa, u32v *bufb, size_t count,
+			ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -194,7 +200,8 @@ int test_div_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_or_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_or_comparison(u32v *bufa, u32v *bufb, size_t count,
+		       ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -208,7 +215,8 @@ int test_or_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_and_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_and_comparison(u32v *bufa, u32v *bufb, size_t count,
+			ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -222,7 +230,8 @@ int test_and_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_seqinc_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_seqinc_comparison(u32v *bufa, u32v *bufb, size_t count,
+			   ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -234,7 +243,8 @@ int test_seqinc_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return compare_regions(bufa, bufb, count);
 }
 
-int test_solidbits_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_solidbits_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -248,6 +258,10 @@ int test_solidbits_comparison(u32v *bufa, u32v *bufb, size_t count)
 	for (j = 0; j < 64; j++) {
 		printf("\b\b\b\b\b\b\b\b\b\b\b");
 		q = (j % 2) == 0 ? UL_ONEBITS : 0;
+		if (fix_level)
+			q |= fix_bit;
+		else
+			q &= ~fix_bit;
 		data[0] = data[2] = q;
 		data[1] = data[3] = ~q;
 		data_cpu_2_io(data, sizeof(data));
@@ -268,7 +282,8 @@ int test_solidbits_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_checkerboard_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_checkerboard_comparison(u32v *bufa, u32v *bufb, size_t count,
+				 ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -282,6 +297,11 @@ int test_checkerboard_comparison(u32v *bufa, u32v *bufb, size_t count)
 	for (j = 0; j < 64; j++) {
 		printf("\b\b\b\b\b\b\b\b\b\b\b");
 		q = (j % 2) == 0 ? CHECKERBOARD1 : CHECKERBOARD2;
+		if (fix_level)
+			q |= fix_bit;
+		else
+			q &= ~fix_bit;
+
 		data[0] = data[2] = q;
 		data[1] = data[3] = ~q;
 		data_cpu_2_io(data, sizeof(data));
@@ -302,12 +322,14 @@ int test_checkerboard_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_blockseq_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_blockseq_comparison(u32v *bufa, u32v *bufb, size_t count,
+			     ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
 	unsigned int j;
 	u32 data[4];
+	u32 q;
 	size_t i;
 
 	printf("           ");
@@ -318,8 +340,17 @@ int test_blockseq_comparison(u32v *bufa, u32v *bufb, size_t count)
 		p2 = (u32v *)bufb;
 		printf("setting %3u", j);
 		fflush(stdout);
-		data[0] = data[2] = (u32)UL_BYTE(j);
-		data[1] = data[3] = (u32)UL_BYTE(j);
+		q = (u32)UL_BYTE(j);
+		if (fix_level)
+			q |= fix_bit;
+		else
+			q &= ~fix_bit;
+
+		data[0] = q;
+		data[1] = q;
+		data[2] = q;
+		data[3] = q;
+
 		data_cpu_2_io(data, sizeof(data));
 
 		for (i = 0; i < count; i++)
@@ -335,12 +366,14 @@ int test_blockseq_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_walkbits0_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_walkbits0_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
 	unsigned int j;
 	u32 data[4];
+	u32 q;
 	size_t i;
 
 	printf("           ");
@@ -352,12 +385,19 @@ int test_walkbits0_comparison(u32v *bufa, u32v *bufb, size_t count)
 		printf("setting %3u", j);
 		fflush(stdout);
 		if (j < UL_LEN)
-			data[0] = ONE << j;
+			q = ONE << j;
 		else
-			data[0] = ONE << (UL_LEN * 2 - j - 1);
-		data[1] = data[0];
-		data[2] = data[0];
-		data[3] = data[0];
+			q = ONE << (UL_LEN * 2 - j - 1);
+
+		if (fix_level)
+			q |= fix_bit;
+		else
+			q &= ~fix_bit;
+
+		data[0] = q;
+		data[1] = q;
+		data[2] = q;
+		data[3] = q;
 		data_cpu_2_io(data, sizeof(data));
 
 		for (i = 0; i < count; i++) {
@@ -374,12 +414,14 @@ int test_walkbits0_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_walkbits1_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_walkbits1_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
 	unsigned int j;
 	u32 data[4];
+	u32 q;
 	size_t i;
 
 	printf("           ");
@@ -391,12 +433,18 @@ int test_walkbits1_comparison(u32v *bufa, u32v *bufb, size_t count)
 		printf("setting %3u", j);
 		fflush(stdout);
 		if (j < UL_LEN)
-			data[0] = UL_ONEBITS ^ (ONE << j);
+			q = UL_ONEBITS ^ (ONE << j);
 		else
-			data[0] = UL_ONEBITS ^ (ONE << (UL_LEN * 2 - j - 1));
-		data[1] = data[0];
-		data[2] = data[0];
-		data[3] = data[0];
+			q = UL_ONEBITS ^ (ONE << (UL_LEN * 2 - j - 1));
+		if (fix_level)
+			q |= fix_bit;
+		else
+			q &= ~fix_bit;
+
+		data[0] = q;
+		data[1] = q;
+		data[2] = q;
+		data[3] = q;
 		data_cpu_2_io(data, sizeof(data));
 
 		for (i = 0; i < count; i++) {
@@ -413,7 +461,8 @@ int test_walkbits1_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_bitspread_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_bitspread_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -438,6 +487,13 @@ int test_bitspread_comparison(u32v *bufa, u32v *bufb, size_t count)
 			data[1] = UL_ONEBITS ^ (ONE << (UL_LEN * 2 - 1 - j)
 						| (ONE << (UL_LEN * 2 + 1 - j)));
 		}
+		if (fix_level) {
+			data[0] |= fix_bit;
+			data[1] |= fix_bit;
+		} else {
+			data[0] &= ~fix_bit;
+			data[1] &= ~fix_bit;
+		}
 		data[2] = data[0];
 		data[3] = data[1];
 		data_cpu_2_io(data, sizeof(data));
@@ -456,7 +512,8 @@ int test_bitspread_comparison(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_bitflip_comparison(u32v *bufa, u32v *bufb, size_t count)
+int test_bitflip_comparison(u32v *bufa, u32v *bufb, size_t count,
+			    ul fix_bit, ul fix_level)
 {
 	u32v *p1 = bufa;
 	u32v *p2 = bufb;
@@ -474,6 +531,11 @@ int test_bitflip_comparison(u32v *bufa, u32v *bufb, size_t count)
 			q = ~q;
 			printf("setting %3u", k * 8 + j);
 			fflush(stdout);
+			if (fix_level)
+				q |= fix_bit;
+			else
+				q &= ~fix_bit;
+
 			data[0] = data[2] = q;
 			data[1] = data[3] = ~q;
 			data_cpu_2_io(data, sizeof(data));
@@ -494,7 +556,8 @@ int test_bitflip_comparison(u32v *bufa, u32v *bufb, size_t count)
 }
 
 #ifdef TEST_NARROW_WRITES
-int test_8bit_wide_random(u32v *bufa, u32v *bufb, size_t count)
+int test_8bit_wide_random(u32v *bufa, u32v *bufb, size_t count,
+			  ul fix_bit, ul fix_level)
 {
 	u8v *p1, *t;
 	u32v *p2;
@@ -531,7 +594,8 @@ int test_8bit_wide_random(u32v *bufa, u32v *bufb, size_t count)
 	return 0;
 }
 
-int test_16bit_wide_random(u32v *bufa, u32v *bufb, size_t count)
+int test_16bit_wide_random(u32v *bufa, u32v *bufb, size_t count,
+			   ul fix_bit, ul fix_level)
 {
 	u16v *p1, *t;
 	u32v *p2;
diff --git a/cmd/memtester/tests.h b/cmd/memtester/tests.h
index cfd096e560..b3ddcaed2e 100644
--- a/cmd/memtester/tests.h
+++ b/cmd/memtester/tests.h
@@ -19,38 +19,38 @@
 
 int test_stuck_address(u32v *bufa, size_t count);
 int test_random_value(u32v *bufa,
-		      u32v *bufb, size_t count);
+		      u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_xor_comparison(u32v *bufa,
-			u32v *bufb, size_t count);
+			u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_sub_comparison(u32v *bufa,
-			u32v *bufb, size_t count);
+			u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_mul_comparison(u32v *bufa,
-			u32v *bufb, size_t count);
+			u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_div_comparison(u32v *bufa,
-			u32v *bufb, size_t count);
+			u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_or_comparison(u32v *bufa,
-		       u32v *bufb, size_t count);
+		       u32v *bufb, size_t count, ul fix_bit, ul fix_level);
 int test_and_comparison(u32v *bufa,
-			u32v *bufb, size_t count);
-int test_seqinc_comparison(u32v *bufa,
-			   u32v *bufb, size_t count);
-int test_solidbits_comparison(u32v *bufa,
-			      u32v *bufb, size_t count);
-int test_checkerboard_comparison(u32v *bufa,
-				 u32v *bufb, size_t count);
-int test_blockseq_comparison(u32v *bufa,
-			     u32v *bufb, size_t count);
-int test_walkbits0_comparison(u32v *bufa,
-			      u32v *bufb, size_t count);
-int test_walkbits1_comparison(u32v *bufa,
-			      u32v *bufb, size_t count);
-int test_bitspread_comparison(u32v *bufa,
-			      u32v *bufb, size_t count);
-int test_bitflip_comparison(u32v *bufa,
-			    u32v *bufb, size_t count);
+			u32v *bufb, size_t count, ul fix_bit, ul fix_level);
+int test_seqinc_comparison(u32v *bufa, u32v *bufb, size_t count,
+			   ul fix_bit, ul fix_level);
+int test_solidbits_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level);
+int test_checkerboard_comparison(u32v *bufa, u32v *bufb, size_t count,
+				 ul fix_bit, ul fix_level);
+int test_blockseq_comparison(u32v *bufa, u32v *bufb, size_t count,
+			     ul fix_bit, ul fix_level);
+int test_walkbits0_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level);
+int test_walkbits1_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level);
+int test_bitspread_comparison(u32v *bufa, u32v *bufb, size_t count,
+			      ul fix_bit, ul fix_level);
+int test_bitflip_comparison(u32v *bufa, u32v *bufb, size_t count,
+			    ul fix_bit, ul fix_level);
 #ifdef TEST_NARROW_WRITES
-int test_8bit_wide_random(u32v *bufa,
-			  u32v *bufb, size_t count);
-int test_16bit_wide_random(u32v *bufa,
-			   u32v *bufb, size_t count);
+int test_8bit_wide_random(u32v *bufa, u32v *bufb, size_t count,
+			  ul fix_bit, ul fix_level);
+int test_16bit_wide_random(u32v *bufa, u32v *bufb, size_t count,
+			   ul fix_bit, ul fix_level);
 #endif
diff --git a/cmd/memtester/types.h b/cmd/memtester/types.h
index 4442eb3c2e..3fa4ca5c9d 100644
--- a/cmd/memtester/types.h
+++ b/cmd/memtester/types.h
@@ -24,7 +24,8 @@ typedef unsigned short volatile u16v;
 
 struct test {
 	char *name;
-	int (*fp)(u32v *bufa, u32v *bufb, size_t count);
+	int (*fp)(u32v *bufa, u32v *bufb, size_t count,
+		  ul fix_bit, ul fix_level);
 };
 
 #endif /* __MEMTESTER_TYPES_H */