diff --git a/arch/arm/src/sam34/chip/sam4cm_vectors.h b/arch/arm/src/sam34/chip/sam4cm_vectors.h
index 09b4f30fca..9afd594ef9 100644
--- a/arch/arm/src/sam34/chip/sam4cm_vectors.h
+++ b/arch/arm/src/sam34/chip/sam4cm_vectors.h
@@ -64,7 +64,7 @@
   UNUSED(SAM_IRQ_RESERVED_7)          /* Vector 16+7: Reserved */
   VECTOR(sam_uart0, SAM_IRQ_UART0)    /* Vector 16+8: Universal Asynchronous Receiver Transmitter 0 */
   UNUSED(SAM_IRQ_RESERVED_9)          /* Vector 16+9: Reserved */
-//VECTOR(sam_smc, SAM_IRQ_SMC)        /* Vector 16+10: Static Memory Controller */
+  UNUSED(SAM_IRQ_RESERVED_10)         /* Vector 16+10: Unused */
   VECTOR(sam_pioa, SAM_IRQ_PIOA)      /* Vector 16+11: Parallel I/O Controller A */
   VECTOR(sam_piob, SAM_IRQ_PIOB)      /* Vector 16+12: Parallel I/O Controller B */
   UNUSED(SAM_IRQ_RESERVED_13)         /* Vector 16+13: Reserved */
diff --git a/arch/arm/src/sam34/chip/sam_pmc.h b/arch/arm/src/sam34/chip/sam_pmc.h
index 6ad528d5a1..c22c2f0bf0 100644
--- a/arch/arm/src/sam34/chip/sam_pmc.h
+++ b/arch/arm/src/sam34/chip/sam_pmc.h
@@ -414,19 +414,19 @@
 /* PMC Programmable Clock Register (0,1,2) */
 
 #define PMC_PCK_CSS_SHIFT                (0)       /* Bits 0-2: Master Clock Source Selection */
-#define PMC_PCK_CSS_MASK                 (7 << PMC_PCK_CSS_MASK)
-#  define PMC_PCK_CSS_SLOW               (0 << PMC_PCK_CSS_MASK) /* Slow Clock */
-#  define PMC_PCK_CSS_MAIN               (1 << PMC_PCK_CSS_MASK) /* Main Clock */
-#  define PMC_PCK_CSS_PLLA               (2 << PMC_PCK_CSS_MASK) /* PLLA Clock */
+#define PMC_PCK_CSS_MASK                 (7 << PMC_PCK_CSS_SHIFT)
+#  define PMC_PCK_CSS_SLOW               (0 << PMC_PCK_CSS_SHIFT) /* Slow Clock */
+#  define PMC_PCK_CSS_MAIN               (1 << PMC_PCK_CSS_SHIFT) /* Main Clock */
+#  define PMC_PCK_CSS_PLLA               (2 << PMC_PCK_CSS_SHIFT) /* PLLA Clock */
 
-#if defined(CONFIG_ARCH_CHIP_SAM4S)
-#  define PMC_PCK_CSS_PLLB               (3 << PMC_PCK_CSS_MASK) /* PLLB Clock */
+#if defined(CONFIG_ARCH_CHIP_SAM4CM) || defined(CONFIG_ARCH_CHIP_SAM4S)
+#  define PMC_PCK_CSS_PLLB               (3 << PMC_PCK_CSS_SHIFT) /* PLLB Clock */
 #elif defined(CONFIG_ARCH_CHIP_SAM3X) || defined(CONFIG_ARCH_CHIP_SAM3A) || \
       defined(CONFIG_ARCH_CHIP_SAM3U)
-#  define PMC_PCK_CSS_UPLL               (3 << PMC_PCK_CSS_MASK) /* UPLL Clock */
+#  define PMC_PCK_CSS_UPLL               (3 << PMC_PCK_CSS_SHIFT) /* UPLL Clock */
 #endif
 
-#  define PMC_PCK_CSS_MCK                (4 << PMC_PCK_CSS_MASK) /* Master Clock */
+#  define PMC_PCK_CSS_MCK                (4 << PMC_PCK_CSS_SHIFT) /* Master Clock */
 
 #define PMC_PCK_PRES_SHIFT               (4)       /* Bits 4-6: Programmable Clock Prescaler */
 #define PMC_PCK_PRES_MASK                (7 << PMC_PCK_PRES_SHIFT)
diff --git a/arch/arm/src/sam34/sam_clockconfig.c b/arch/arm/src/sam34/sam_clockconfig.c
index fa830a2fb5..46c10c4704 100644
--- a/arch/arm/src/sam34/sam_clockconfig.c
+++ b/arch/arm/src/sam34/sam_clockconfig.c
@@ -239,16 +239,16 @@ static inline void sam_pmcsetup(void)
   //putreg32(PMC_PMMR_MASK, SAM_PMC_PMMR);
 #endif
 
+  /* Setup PLLA and wait for LOCKA */
+
+  putreg32(BOARD_CKGR_PLLAR, SAM_PMC_CKGR_PLLAR);
+  sam_pmcwait(PMC_INT_LOCKA);
+
 #ifdef CONFIG_ARCH_CHIP_SAM4CM
   /* Setup PLLB and wait for LOCKB */
 
   putreg32(BOARD_CKGR_PLLBR, SAM_PMC_CKGR_PLLBR);
   sam_pmcwait(PMC_INT_LOCKB);
-#else
-  /* Setup PLLA and wait for LOCKA */
-
-  putreg32(BOARD_CKGR_PLLAR, SAM_PMC_CKGR_PLLAR);
-  sam_pmcwait(PMC_INT_LOCKA);
 #endif
 
 #ifdef CONFIG_USBDEV