diff --git a/arch/arm/src/samv7/sam_rswdt.c b/arch/arm/src/samv7/sam_rswdt.c
new file mode 100644
index 00000000000..0d92c40dfdd
--- /dev/null
+++ b/arch/arm/src/samv7/sam_rswdt.c
@@ -0,0 +1,705 @@
+/****************************************************************************
+ * arch/arm/src/samv7/sam_rswdg.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/arch.h>
+
+#include <stdint.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/timers/watchdog.h>
+#include <arch/board/board.h>
+
+#include "up_arch.h"
+#include "sam_wdt.h"
+
+#if defined(CONFIG_WATCHDOG) && defined(CONFIG_SAMV7_RSWDT)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+/* Configuration ************************************************************/
+/* The Watchdog Timer uses the Slow Clock divided by 128 to establish the
+ * maximum Watchdog period to be 16 seconds (with a typical Slow Clock of
+ * 32768 kHz).
+ */
+
+#ifndef BOARD_SCLK_FREQUENCY
+#  define BOARD_SCLK_FREQUENCY 32768
+#endif
+
+#define RSWDT_FREQUENCY (BOARD_SCLK_FREQUENCY / 128)
+
+/* At 32768Hz, the maximum timeout value will be:
+ *
+ *   4096 / RSWDT_FREQUENCY = 256 seconds or 16,000 milliseconds
+ *
+ * And the minimum (non-zero) timeout would be:
+ *
+ *   1 / RSWDT_FREQUENCY = 3.9 milliseconds
+ */
+
+#define RSWDT_MINTIMEOUT ((1000 + RSWDT_FREQUENCY - 1) / RSWDT_FREQUENCY)
+#define RSWDT_MAXTIMEOUT ((4096 * 1000) / RSWDT_FREQUENCY)
+
+/* Debug ********************************************************************/
+/* Non-standard debug that may be enabled just for testing the watchdog
+ * driver.  NOTE: that only lldbg types are used so that the output is
+ * immediately available.
+ */
+
+#ifdef CONFIG_DEBUG_WATCHDOG
+#  define wddbg    lldbg
+#  define wdvdbg   llvdbg
+#else
+#  define wddbg(x...)
+#  define wdvdbg(x...)
+#endif
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+/* This structure provides the private representation of the "lower-half"
+ * driver state structure.  This structure must be cast-compatible with the
+ * well-known watchdog_lowerhalf_s structure.
+ */
+
+struct sam_lowerhalf_s
+{
+  FAR const struct watchdog_ops_s  *ops;  /* Lower half operations */
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+  xcpt_t   handler;  /* Current RSWDT interrupt handler */
+#endif
+  uint32_t timeout;  /* The actual timeout value (milliseconds) */
+  uint16_t reload;   /* The 12-bit watchdog reload value */
+  bool     started;  /* The timer has been started */
+};
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+/* Register operations ******************************************************/
+
+#if defined(CONFIG_SAMV7_RSWDT_REGDEBUG) && defined(CONFIG_DEBUG)
+static uint32_t sam_getreg(uintptr_t regaddr);
+static void     sam_putreg(uint32_t regval, uintptr_t regaddr);
+#else
+# define        sam_getreg(regaddr)        getreg32(regaddr)
+# define        sam_putreg(regval,regaddr) putreg32(regval,regaddr)
+#endif
+
+/* Interrupt hanlding *******************************************************/
+
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+static int      sam_interrupt(int irq, FAR void *context);
+#endif
+
+/* "Lower half" driver methods **********************************************/
+
+static int      sam_start(FAR struct watchdog_lowerhalf_s *lower);
+static int      sam_stop(FAR struct watchdog_lowerhalf_s *lower);
+static int      sam_keepalive(FAR struct watchdog_lowerhalf_s *lower);
+static int      sam_getstatus(FAR struct watchdog_lowerhalf_s *lower,
+                  FAR struct watchdog_status_s *status);
+static int      sam_settimeout(FAR struct watchdog_lowerhalf_s *lower,
+                  uint32_t timeout);
+static xcpt_t   sam_capture(FAR struct watchdog_lowerhalf_s *lower,
+                  xcpt_t handler);
+static int      sam_ioctl(FAR struct watchdog_lowerhalf_s *lower, int cmd,
+                  unsigned long arg);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+/* "Lower half" driver methods */
+
+static const struct watchdog_ops_s g_wdgops =
+{
+  .start      = sam_start,
+  .stop       = sam_stop,
+  .keepalive  = sam_keepalive,
+  .getstatus  = sam_getstatus,
+  .settimeout = sam_settimeout,
+  .capture    = sam_capture,
+  .ioctl      = sam_ioctl,
+};
+
+/* "Lower half" driver state */
+
+static struct sam_lowerhalf_s g_wdtdev;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: sam_getreg
+ *
+ * Description:
+ *   Get the contents of an SAMV7 register
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_SAMV7_RSWDT_REGDEBUG) && defined(CONFIG_DEBUG)
+static uint32_t sam_getreg(uintptr_t regaddr)
+{
+  static uint32_t prevaddr = 0;
+  static uint32_t count    = 0;
+  static uint32_t preval   = 0;
+
+  /* Read the value from the register */
+
+  uint32_t regval = getreg32(regaddr);
+
+  /* Is this the same value that we read from the same registe last time?  Are
+   * we polling the register?  If so, suppress some of the output.
+   */
+
+  if (regaddr == prevaddr && regval == preval)
+    {
+      if (count == 0xffffffff || ++count > 3)
+        {
+          if (count == 4)
+            {
+              lldbg("...\n");
+            }
+
+          return regval;
+        }
+    }
+
+  /* No this is a new address or value */
+
+  else
+    {
+      /* Did we print "..." for the previous value? */
+
+      if (count > 3)
+        {
+          /* Yes.. then show how many times the value repeated */
+
+          lldbg("[repeats %d more times]\n", count-3);
+        }
+
+      /* Save the new address, value, and count */
+
+      prevaddr = regaddr;
+      preval   = regval;
+      count    = 1;
+    }
+
+  /* Show the register value read */
+
+  lldbg("%08x->%048\n", regaddr, regval);
+  return regval;
+}
+#endif
+
+/****************************************************************************
+ * Name: sam_putreg
+ *
+ * Description:
+ *   Set the contents of an SAMV7 register to a value
+ *
+ ****************************************************************************/
+
+#if defined(CONFIG_SAMV7_RSWDT_REGDEBUG) && defined(CONFIG_DEBUG)
+static void sam_putreg(uint32_t regval, uintptr_t regaddr)
+{
+  /* Show the register value being written */
+
+  lldbg("%08x<-%08x\n", regaddr, regval);
+
+  /* Write the value */
+
+  putreg32(regval, regaddr);
+}
+#endif
+
+/****************************************************************************
+ * Name: sam_interrupt
+ *
+ * Description:
+ *   RSWDT early warning interrupt
+ *
+ * Input Parameters:
+ *   Usual interrupt handler arguments.
+ *
+ * Returned Values:
+ *   Always returns OK.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+static int sam_interrupt(int irq, FAR void *context)
+{
+  FAR struct sam_lowerhalf_s *priv = &g_wdtdev;
+
+  /* Is there a registered handler? */
+
+  if (priv->handler)
+    {
+      /* Yes... NOTE:  This interrupt service routine (ISR) must reload
+       * the RSWDT counter to prevent the reset.  Otherwise, we will reset
+       * upon return.
+       */
+
+      priv->handler(irq, context);
+    }
+
+  return OK;
+}
+#endif
+
+/****************************************************************************
+ * Name: sam_start
+ *
+ * Description:
+ *   Start the watchdog timer, resetting the time to the current timeout,
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of the "lower-half"
+ *           driver state structure.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_start(FAR struct watchdog_lowerhalf_s *lower)
+{
+  FAR struct sam_lowerhalf_s *priv = (FAR struct sam_lowerhalf_s *)lower;
+
+  /* The watchdog timer is enabled or disabled by writing to the MR register.
+   *
+   * NOTE: The Watchdog Mode Register (RSWDT_MR) can be written only once.  Only
+   * a processor reset resets it.  Writing the RSWDT_MR register reloads the
+   * timer with the newly programmed mode parameters.
+   */
+
+  wdvdbg("Entry\n");
+  return priv->started ? OK : -ENOSYS;
+}
+
+/****************************************************************************
+ * Name: sam_stop
+ *
+ * Description:
+ *   Stop the watchdog timer
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of the "lower-half"
+ *           driver state structure.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_stop(FAR struct watchdog_lowerhalf_s *lower)
+{
+  /* The watchdog timer is enabled or disabled by writing to the MR register.
+   *
+   * NOTE: The Watchdog Mode Register (RSWDT_MR) can be written only once.  Only
+   * a processor reset resets it.  Writing the RSWDT_MR register reloads the
+   * timer with the newly programmed mode parameters.
+   */
+
+  wdvdbg("Entry\n");
+  return -ENOSYS;
+}
+
+/****************************************************************************
+ * Name: sam_keepalive
+ *
+ * Description:
+ *   Reset the watchdog timer to the current timeout value, prevent any
+ *   imminent watchdog timeouts.  This is sometimes referred as "pinging"
+ *   the atchdog timer or "petting the dog".
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of the "lower-half"
+ *           driver state structure.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_keepalive(FAR struct watchdog_lowerhalf_s *lower)
+{
+  wdvdbg("Entry\n");
+
+  /* Write RSWDT_CR_WDRSTT to the RSWDT CR regiser (along with the KEY value)
+   * will restart the watchdog timer.
+   */
+
+  sam_putreg(WDT_CR_WDRSTT | RSWDT_CR_KEY, SAM_RSWDT_CR);
+  return OK;
+}
+
+/****************************************************************************
+ * Name: sam_getstatus
+ *
+ * Description:
+ *   Get the current watchdog timer status
+ *
+ * Input Parameters:
+ *   lower   - A pointer the publicly visible representation of the "lower-half"
+ *             driver state structure.
+ *   stawtus - The location to return the watchdog status information.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_getstatus(FAR struct watchdog_lowerhalf_s *lower,
+                         FAR struct watchdog_status_s *status)
+{
+  FAR struct sam_lowerhalf_s *priv = (FAR struct sam_lowerhalf_s *)lower;
+
+  wdvdbg("Entry\n");
+  DEBUGASSERT(priv);
+
+  /* Return the status bit */
+
+  status->flags = WDFLAGS_RESET;
+  if (priv->started)
+    {
+      status->flags |= WDFLAGS_ACTIVE;
+    }
+
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+  if (priv->handler)
+    {
+      status->flags |= WDFLAGS_CAPTURE;
+    }
+#endif
+
+  /* Return the actual timeout is milliseconds */
+
+  status->timeout = priv->timeout;
+
+  /* Get the time remaining until the watchdog expires (in milliseconds)
+   *
+   * REVISIT:  I think this that this information is available.
+   */
+
+  status->timeleft = 0;
+
+  wdvdbg("Status     :\n");
+  wdvdbg("  flags    : %08x\n", status->flags);
+  wdvdbg("  timeout  : %d\n", status->timeout);
+  wdvdbg("  timeleft : %d\n", status->timeleft);
+  return OK;
+}
+
+/****************************************************************************
+ * Name: sam_settimeout
+ *
+ * Description:
+ *   Set a new timeout value (and reset the watchdog timer)
+ *
+ * Input Parameters:
+ *   lower   - A pointer the publicly visible representation of the "lower-half"
+ *             driver state structure.
+ *   timeout - The new timeout value in millisecnds.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_settimeout(FAR struct watchdog_lowerhalf_s *lower,
+                            uint32_t timeout)
+{
+  FAR struct sam_lowerhalf_s *priv = (FAR struct sam_lowerhalf_s *)lower;
+  uint32_t reload;
+  uint32_t regval;
+
+  DEBUGASSERT(priv);
+  wdvdbg("Entry: timeout=%d\n", timeout);
+
+  /* Can this timeout be represented? */
+
+  if (timeout < RSWDT_MINTIMEOUT || timeout >= RSWDT_MAXTIMEOUT)
+    {
+      wddbg("Cannot represent timeout: %d < %d > %d\n",
+            RSWDT_MINTIMEOUT, timeout, RSWDT_MAXTIMEOUT);
+      return -ERANGE;
+    }
+
+  /* Calculate the reload value to achiee this (appoximate) timeout.
+   *
+   * Examples with RSWDT_FREQUENCY = 32768 / 128 = 256:
+   *  timeout = 4     -> reload = 1
+   *  timeout = 16000 -> reload = 4096
+   */
+
+  reload = (timeout * RSWDT_FREQUENCY + 500) / 1000;
+  if (reload < 1)
+    {
+      reload = 1;
+    }
+  else if (reload > 4095)
+    {
+      reload = 4095;
+    }
+
+  /* Calculate and save the actual timeout value in milliseconds:
+   *
+   * timeout =  1000 * (reload + 1) / Fwwdg
+   */
+
+  priv->timeout = (1000 * reload + RSWDT_FREQUENCY/2) / RSWDT_FREQUENCY;
+
+  /* Remember the selected values */
+
+  priv->reload = reload;
+
+  wdvdbg("reload=%d timout: %d->%d\n",
+         reload, timeout, priv->timeout);
+
+  /* Set the RSWDT_MR according to calculated value
+   *
+   * NOTE: The Watchdog Mode Register (RSWDT_MR) can be written only once.  Only
+   * a processor reset resets it.  Writing the RSWDT_MR register reloads the
+   * timer with the newly programmed mode parameters.
+   */
+
+  regval = WDT_MR_WDV(reload) | RSWDT_MR_WDD_ALLONES;
+
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+  /* Generate an interrupt whent he watchdog timer expires */
+
+  regval |= WDT_MR_WDFIEN;
+#else
+  /* Reset (everything) if the watchdog timer expires.
+   *
+   * REVISIT:  Set WDT_MR_WDRPROC so that only the processor is reset?
+   */
+
+  regval |= WDT_MR_WDRSTEN;
+#endif
+
+#ifdef CONFIG_SAMV7_RSWDT_DEBUGHALT
+  /* Halt the watchdog in the debug state */
+
+  regval |= WDT_MR_WDDBGHLT;
+#endif
+
+#ifdef CONFIG_SAMV7_RSWDT_IDLEHALT
+  /* Halt the watchdog in the IDLE mode */
+
+  regval |= WDT_MR_WDIDLEHLT;
+#endif
+
+  sam_putreg(regval, SAM_RSWDT_MR);
+
+  /* NOTE:  We had to start the watchdog here (because we cannot re-write the
+   * MR register).  So sam_start will not be able to do anything.
+   */
+
+  priv->started = true;
+
+  wdvdbg("Setup: CR: %08x MR: %08x SR: %08x\n",
+         sam_getreg(SAM_RSWDT_CR), sam_getreg(SAM_RSWDT_MR),
+         sam_getreg(SAM_RSWDT_SR));
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: sam_capture
+ *
+ * Description:
+ *   Don't reset on watchdog timer timeout; instead, call this user provider
+ *   timeout handler.  NOTE:  Providing handler==NULL will restore the reset
+ *   behavior.
+ *
+ * Input Parameters:
+ *   lower      - A pointer the publicly visible representation of the "lower-half"
+ *                driver state structure.
+ *   newhandler - The new watchdog expiration function pointer.  If this
+ *                function pointer is NULL, then the reset-on-expiration
+ *                behavior is restored,
+ *
+ * Returned Values:
+ *   The previous watchdog expiration function pointer or NULL is there was
+ *   no previous function pointer, i.e., if the previous behavior was
+ *   reset-on-expiration (NULL is also returned if an error occurs).
+ *
+ ****************************************************************************/
+
+static xcpt_t sam_capture(FAR struct watchdog_lowerhalf_s *lower,
+                            xcpt_t handler)
+{
+#ifndef CONFIG_SAMV7_RSWDT_INTERRUPT
+  wddbg("ERROR: Not configured for this mode\n");
+  return NULL;
+#else
+  FAR struct sam_lowerhalf_s *priv = (FAR struct sam_lowerhalf_s *)lower;
+  irqstate_t flags;
+  xcpt_t oldhandler;
+
+  DEBUGASSERT(priv);
+  wdvdbg("Entry: handler=%p\n", handler);
+
+  /* Get the old handler return value */
+
+  flags = irqsave();
+  oldhandler = priv->handler;
+
+  /* Save the new handler */
+
+   priv->handler = handler;
+
+  /* Are we attaching or detaching the handler? */
+
+  if (handler)
+    {
+      /* Attaching... Enable the RSWDT interrupt */
+
+      up_enable_irq(SAM_IRQ_RSWDT);
+    }
+  else
+    {
+      /* Detaching... Disable the RSWDT interrupt */
+
+      up_disable_irq(SAM_IRQ_RSWDT);
+    }
+
+  irqrestore(flags);
+  return oldhandler;
+#endif
+}
+
+/****************************************************************************
+ * Name: sam_ioctl
+ *
+ * Description:
+ *   Any ioctl commands that are not recognized by the "upper-half" driver
+ *   are forwarded to the lower half driver through this method.
+ *
+ * Input Parameters:
+ *   lower - A pointer the publicly visible representation of the "lower-half"
+ *           driver state structure.
+ *   cmd   - The ioctol command value
+ *   arg   - The optional argument that accompanies the 'cmd'.  The
+ *           interpretation of this argument depends on the particular
+ *           command.
+ *
+ * Returned Values:
+ *   Zero on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+static int sam_ioctl(FAR struct watchdog_lowerhalf_s *lower, int cmd,
+                    unsigned long arg)
+{
+  wdvdbg("cmd=%d arg=%ld\n", cmd, arg);
+
+  /* No ioctls are supported */
+
+  return -ENOTTY;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: up_wdginitialize
+ *
+ * Description:
+ *   Initialize the RSWDT watchdog time.  The watchdog timer is initialized and
+ *   registered as 'devpath.  The initial state of the watchdog time is
+ *   disabled.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Values:
+ *   None
+ *
+ ****************************************************************************/
+
+int up_wdginitialize(void)
+{
+  FAR struct sam_lowerhalf_s *priv = &g_wdtdev;
+
+  wdvdbg("Entry: CR: %08x MR: %08x SR: %08x\n",
+         sam_getreg(SAM_RSWDT_CR), sam_getreg(SAM_RSWDT_MR),
+         sam_getreg(SAM_RSWDT_SR));
+
+  /* Check if some previous logic was disabled the watchdog timer.  Since the
+   * MR can be written only one time, we are out of business if that is the
+   * case.
+   */
+
+  DEBUGASSERT((sam_getreg(SAM_RSWDT_MR) & WDT_MR_WDDIS) == 0);
+
+  /* No clock setup is required.  The Watchdog Timer uses the Slow Clock
+   * divided by 128 to establish the maximum Watchdog period to be 16 seconds
+   * (with a typical Slow Clock of 32768 kHz).
+   */
+
+  /* Initialize the driver state structure.  Here we assume: (1) the state
+   * structure lies in .bss and was zeroed at reset time.  (2) This function
+   * is only called once so it is never necessary to re-zero the structure.
+   */
+
+  priv->ops = &g_wdgops;
+
+#ifdef CONFIG_SAMV7_RSWDT_INTERRUPT
+  /* Attach our RSWDT interrupt handler (But don't enable it yet) */
+
+  (void)irq_attach(SAM_IRQ_RSWDT, sam_interrupt);
+#endif
+
+  /* Register the watchdog driver as /dev/rswdt */
+
+  (void)watchdog_register("/dev/rswdt",
+                         (FAR struct watchdog_lowerhalf_s *)priv);
+  return OK;
+}
+
+#endif /* CONFIG_WATCHDOG && CONFIG_SAMV7_RSWDT */