diff --git a/arch/arm/mach-at91/include/mach/at91_pmc.h b/arch/arm/mach-at91/include/mach/at91_pmc.h
index ebb7dec..8a3fb94 100644
--- a/arch/arm/mach-at91/include/mach/at91_pmc.h
+++ b/arch/arm/mach-at91/include/mach/at91_pmc.h
@@ -158,6 +158,7 @@
 
 #define		AT91_PMC_PCK		(1 <<  0)		/* Processor Clock */
 #define		AT91RM9200_PMC_UDP	(1 <<  1)		/* USB Devcice Port Clock [AT91RM9200 only] */
+#define		AT91_PMC_DDR		(1 <<  2)		/* DDR Clock */
 #define		AT91RM9200_PMC_MCKUDP	(1 <<  2)		/* USB Device Port Master Clock Automatic Disable on Suspend [AT91RM9200 only] */
 #define		AT91RM9200_PMC_UHP	(1 <<  4)		/* USB Host Port Clock [AT91RM9200 only] */
 #define		AT91SAM926x_PMC_UHP	(1 <<  6)		/* USB Host Port Clock [AT91SAM926x only] */
diff --git a/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c b/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
index d2ade4d..2fea56f 100644
--- a/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
+++ b/board/atmel/at91sam9m10g45ek/at91sam9m10g45ek.c
@@ -136,7 +136,7 @@
 	ddr2_conf(&ddr2);
 
 	/* enable DDR2 clock */
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_DDRSDRC0, ATMEL_BASE_CS6, &ddr2);
diff --git a/board/atmel/at91sam9n12ek/at91sam9n12ek.c b/board/atmel/at91sam9n12ek/at91sam9n12ek.c
index 8437f37..59bc535 100644
--- a/board/atmel/at91sam9n12ek/at91sam9n12ek.c
+++ b/board/atmel/at91sam9n12ek/at91sam9n12ek.c
@@ -316,7 +316,7 @@
 	ddr2_conf(&ddr2);
 
 	/* enable DDR2 clock */
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* Chip select 1 is for DDR2/SDRAM */
 	csa = readl(&matrix->ebicsa);
diff --git a/board/atmel/at91sam9x5ek/at91sam9x5ek.c b/board/atmel/at91sam9x5ek/at91sam9x5ek.c
index 0455e2c..1738a2b 100644
--- a/board/atmel/at91sam9x5ek/at91sam9x5ek.c
+++ b/board/atmel/at91sam9x5ek/at91sam9x5ek.c
@@ -353,7 +353,7 @@
 	ddr2_conf(&ddr2);
 
 	/* enable DDR2 clock */
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* Chip select 1 is for DDR2/SDRAM */
 	csa = readl(&matrix->ebicsa);
diff --git a/board/atmel/sama5d3_xplained/sama5d3_xplained.c b/board/atmel/sama5d3_xplained/sama5d3_xplained.c
index 0793e4a..7a01149 100644
--- a/board/atmel/sama5d3_xplained/sama5d3_xplained.c
+++ b/board/atmel/sama5d3_xplained/sama5d3_xplained.c
@@ -191,7 +191,7 @@
 
 	/* enable MPDDR clock */
 	at91_periph_clk_enable(ATMEL_ID_MPDDRC);
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_MPDDRC, ATMEL_BASE_DDRCS, &ddr2);
diff --git a/board/atmel/sama5d3xek/sama5d3xek.c b/board/atmel/sama5d3xek/sama5d3xek.c
index d6e7e16..2bd436a 100644
--- a/board/atmel/sama5d3xek/sama5d3xek.c
+++ b/board/atmel/sama5d3xek/sama5d3xek.c
@@ -430,7 +430,7 @@
 
 	/* enable MPDDR clock */
 	at91_periph_clk_enable(ATMEL_ID_MPDDRC);
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_MPDDRC, ATMEL_BASE_DDRCS, &ddr2);
diff --git a/board/atmel/sama5d4_xplained/sama5d4_xplained.c b/board/atmel/sama5d4_xplained/sama5d4_xplained.c
index 71ec4b7..db45331 100644
--- a/board/atmel/sama5d4_xplained/sama5d4_xplained.c
+++ b/board/atmel/sama5d4_xplained/sama5d4_xplained.c
@@ -390,7 +390,7 @@
 
 	/* enable MPDDR clock */
 	at91_periph_clk_enable(ATMEL_ID_MPDDRC);
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_MPDDRC, ATMEL_BASE_DDRCS, &ddr2);
diff --git a/board/atmel/sama5d4ek/sama5d4ek.c b/board/atmel/sama5d4ek/sama5d4ek.c
index de4291f..357b223 100644
--- a/board/atmel/sama5d4ek/sama5d4ek.c
+++ b/board/atmel/sama5d4ek/sama5d4ek.c
@@ -386,7 +386,7 @@
 
 	/* enable MPDDR clock */
 	at91_periph_clk_enable(ATMEL_ID_MPDDRC);
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_MPDDRC, ATMEL_BASE_DDRCS, &ddr2);
diff --git a/board/siemens/corvus/board.c b/board/siemens/corvus/board.c
index d74743f..3294203 100644
--- a/board/siemens/corvus/board.c
+++ b/board/siemens/corvus/board.c
@@ -149,7 +149,7 @@
 	ddr2_conf(&ddr2);
 
 	/* enable DDR2 clock */
-	writel(0x4, &pmc->scer);
+	writel(AT91_PMC_DDR, &pmc->scer);
 
 	/* DDRAM2 Controller initialize */
 	ddr2_init(ATMEL_BASE_DDRSDRC0, ATMEL_BASE_CS6, &ddr2);