diff --git a/configs/sama5d3x-ek/README.txt b/configs/sama5d3x-ek/README.txt
index 25049c4688..d7260e3cb5 100644
--- a/configs/sama5d3x-ek/README.txt
+++ b/configs/sama5d3x-ek/README.txt
@@ -50,10 +50,9 @@ GNU Toolchain Options
 
   The NuttX make system will support the several different toolchain options.
 
-  All testing has been conducted using the AtmelStudio GCC toolchain.  To use
-  the CodeSourcery, devkitARM or other GNU toolchain, you simply need to add
-  add one of the following configuration options to your .config (or defconfig)
-  file:
+  All testing has been conducted using the CodeSourcery GCC toolchain.  To use
+  a different toolchain, you simply need to add change to one of the following
+  configuration options to your .config (or defconfig) file:
 
     CONFIG_ARMV7A_TOOLCHAIN_CODESOURCERYW=y  : CodeSourcery under Windows
     CONFIG_ARMV7A_TOOLCHAIN_CODESOURCERYL=y  : CodeSourcery under Linux
@@ -63,8 +62,9 @@ GNU Toolchain Options
     CONFIG_ARMV7A_TOOLCHAIN_GNU_EABIL=y      : Generic GCC ARM EABI toolchain for Linux
     CONFIG_ARMV7A_TOOLCHAIN_GNU_EABIW=y      : Generic GCC ARM EABI toolchain for Windows
 
-  The AtmelStudio GCC toolchain is selected with CONFIG_ARMV7A_TOOLCHAIN_GNU_EABIW=y
-  and setting the PATH variable appropriately.
+  The CodeSourcery GCC toolchain is selected with
+  CONFIG_ARMV7A_TOOLCHAIN_GNU_EABIW=y and setting the PATH variable
+  appropriately.
 
   If you are not using AtmelStudio GCC toolchain, then you may also have to
   modify the PATH in the setenv.h file if your make cannot find the tools.
diff --git a/configs/sama5d3x-ek/include/board.h b/configs/sama5d3x-ek/include/board.h
index 8759dce559..4bc9de1433 100644
--- a/configs/sama5d3x-ek/include/board.h
+++ b/configs/sama5d3x-ek/include/board.h
@@ -47,10 +47,90 @@
  ************************************************************************************/
 
 /* Clocking *************************************************************************/
+/* After power-on reset, the sam3u device is running on a 4MHz internal RC.  These
+ * definitions will configure clocking
+ *
+ *   MAINOSC:  Frequency = 12MHz (crysta)
+ *   PLLA: PLL Divider = 1, Multiplier = 16 to generate PLLACK = 192MHz
+ *   Master Clock (MCK): Source = PLLACK, Prescalar = 1 to generate MCK = 96MHz
+ *   CPU clock: 96MHz
+ */
 
-/* Resulting clock frquencies *******************************************************/
+/* Main oscillator register settings.
+ *
+ *   The start up time should be should be:
+ *   Start Up Time = 8 * MOSCXTST / SLCK = 56 Slow Clock Cycles.
+ */
 
-#define BOARD_MCK_FREQUENCY 0 /* FIXME */
+#define BOARD_CKGR_MOR_MOSCXTST    (62 << PMC_CKGR_MOR_MOSCXTST_SHIFT) /* Start-up Time */
+
+/* PLLA configuration.
+ *
+ *   Divider = 1
+ *   Multipler = 16
+ */
+
+#define BOARD_CKGR_PLLAR_MUL       (15 << PMC_CKGR_PLLAR_MUL_SHIFT)
+#define BOARD_CKGR_PLLAR_STMODE    PMC_CKGR_PLLAR_STMODE_FAST
+#define BOARD_CKGR_PLLAR_COUNT     (63 << PMC_CKGR_PLLAR_COUNT_SHIFT)
+#define BOARD_CKGR_PLLAR_DIV       PMC_CKGR_PLLAR_DIV_BYPASS
+
+/* PMC master clock register settings.
+ *
+ *  Source = PLLA
+ *  Divider = 2
+ */
+
+#define BOARD_PMC_MCKR_CSS         PMC_MCKR_CSS_PLLA
+#define BOARD_PMC_MCKR_PRES        PMC_MCKR_PRES_DIV2
+
+/* USB UTMI PLL start-up time */
+
+#define BOARD_CKGR_UCKR_UPLLCOUNT  (3 << PMC_CKGR_UCKR_UPLLCOUNT_SHIFT)
+
+/* Resulting frequencies */
+
+#define BOARD_MAINOSC_FREQUENCY    (12000000)  /* MAINOSC: 12MHz crystal on-board */
+#define BOARD_PLLA_FREQUENCY       (192000000) /* PLLACK:  16 * 12Mhz / 1 */
+#define BOARD_MCK_FREQUENCY        (96000000)  /* MCK:     PLLACK / 2 */
+#define BOARD_CPU_FREQUENCY        (96000000)  /* CPU:     MCK */
+
+/* HSMCI clocking
+ *
+ * Multimedia Card Interface clock (MCCK or MCI_CK) is Master Clock (MCK)
+ * divided by (2*(CLKDIV+1)).
+ *
+ *   MCI_SPEED = MCK / (2*(CLKDIV+1))
+ *   CLKDIV = MCI / MCI_SPEED / 2 - 1
+ *
+ * Where CLKDIV has a range of 0-255.
+ */
+
+/* MCK = 96MHz, CLKDIV = 119, MCI_SPEED = 96MHz / 2 * (119+1) = 400 KHz */
+
+#define HSMCI_INIT_CLKDIV          (119 << HSMCI_MR_CLKDIV_SHIFT)
+
+/* MCK = 96MHz, CLKDIV = 3, MCI_SPEED = 96MHz / 2 * (3+1) = 12 MHz */
+
+#define HSMCI_MMCXFR_CLKDIV        (3 << HSMCI_MR_CLKDIV_SHIFT)
+
+/* MCK = 96MHz, CLKDIV = 1, MCI_SPEED = 96MHz / 2 * (1+1) = 24 MHz */
+
+#define HSMCI_SDXFR_CLKDIV         (1 << HSMCI_MR_CLKDIV_SHIFT)
+#define HSMCI_SDWIDEXFR_CLKDIV     HSMCI_SDXFR_CLKDIV
+
+/* FLASH wait states
+ *
+ * FWS Max frequency
+ *     1.62V 1.8V
+ * --- ----- ------
+ *  0  24MHz 27MHz
+ *  1  40MHz 47MHz
+ *  2  72MHz 84MHz
+ *  3  84MHz 96MHz
+ */
+
+#define BOARD_FWS                  3
 
 /* LED definitions ******************************************************************/
 
diff --git a/configs/sama5d3x-ek/ostest/setenv.sh b/configs/sama5d3x-ek/ostest/setenv.sh
index 1378d42985..9b2028586a 100755
--- a/configs/sama5d3x-ek/ostest/setenv.sh
+++ b/configs/sama5d3x-ek/ostest/setenv.sh
@@ -50,12 +50,13 @@ fi
 # This is the Cygwin path to the location where I installed the Atmel GCC
 # toolchain under Windows.  You will also have to edit this if you install
 # this toolchain in any other location
-export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
+#export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/Atmel/Atmel Toolchain/ARM GCC/Native/4.7.3.99/arm-gnu-toolchain/bin"
 
 # This is the Cygwin path to the location where I installed the CodeSourcery
 # toolchain under windows.  You will also have to edit this if you install
 # the CodeSourcery toolchain in any other location
 #export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery G++ Lite/bin"
+export TOOLCHAIN_BIN="/cygdrive/c/Program Files (x86)/CodeSourcery/Sourcery_CodeBench_Lite_for_ARM_EABI/bin"
 
 # These are the Cygwin paths to the locations where I installed the Atollic
 # toolchain under windows.  You will also have to edit this if you install