diff --git a/arch/arm/cpu/armv7/at91/sama5d3_devices.c b/arch/arm/cpu/armv7/at91/sama5d3_devices.c
index 7ebee87..78ecfc8 100644
--- a/arch/arm/cpu/armv7/at91/sama5d3_devices.c
+++ b/arch/arm/cpu/armv7/at91/sama5d3_devices.c
@@ -84,7 +84,7 @@ void at91_seriald_hw_init(void)
 	at91_set_a_periph(AT91_PIO_PORTB, 30, 0);	/* DRXD */
 
 	/* Enable clock */
-	at91_periph_clk_enable(ATMEL_ID_SYS);
+	at91_periph_clk_enable(ATMEL_ID_DBGU);
 }
 
 #if defined(CONFIG_ATMEL_SPI)
diff --git a/arch/arm/cpu/armv7/at91/timer.c b/arch/arm/cpu/armv7/at91/timer.c
index 3808aed..e3ebfe0 100644
--- a/arch/arm/cpu/armv7/at91/timer.c
+++ b/arch/arm/cpu/armv7/at91/timer.c
@@ -60,7 +60,7 @@ int timer_init(void)
 	at91_pit_t *pit = (at91_pit_t *)ATMEL_BASE_PIT;
 
 	/* Enable PITC Clock */
-	at91_periph_clk_enable(ATMEL_ID_SYS);
+	at91_periph_clk_enable(ATMEL_ID_PIT);
 
 	/* Enable PITC */
 	writel(TIMER_LOAD_VAL | AT91_PIT_MR_EN , &pit->mr);