Add ioctl's to support XIP

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@913 42af7a65-404d-4744-a932-0658087f49c3

8 files changed, 332 insertions, 139 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index fca27df5f..80b498c72 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -466,4 +466,10 @@
 	* Added support for ROMFS filesystem.
 	* Added a simple test the ROMFS filesystem (examples/romfs)
 	* NSH: Use ROMFS to provide an option for a start-up script at /etc/init.d/rcS
+	* Add definition of BIOC_XIPBASE ioctl and implement in RAM disk block driver.
+	  This is a low level requirement for eXecute In Place (XIP) support.
+	* Add a FIOC_MMAP to perform memory mapping of a file and implemented the
+	  ioctl command in the ROMFS filesystem.  This is a requirement for eXecute
+	  In Place (XIP) support.
+
 
diff --git a/nuttx/Documentation/NuttX.html b/nuttx/Documentation/NuttX.html
index 3ee7c80b7..b1e1b1c7d 100644
--- a/nuttx/Documentation/NuttX.html
+++ b/nuttx/Documentation/NuttX.html
@@ -8,7 +8,7 @@
   <tr align="center" bgcolor="#e4e4e4">
     <td>
       <h1><big><font color="#3c34ec"><i>NuttX RTOS</i></font></big></h1>
-      <p>Last Updated: September 11, 2008</p>
+      <p>Last Updated: September 12, 2008</p>
     </td>
   </tr>
 </table>
@@ -1100,6 +1100,11 @@ nuttx-0.3.15 2008-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 	* Added support for ROMFS filesystem.
 	* Added a simple test the ROMFS filesystem (examples/romfs)
 	* NSH: Use ROMFS to provide an option for a start-up script at /etc/init.d/rcS
+	* Add definition of BIOC_XIPBASE ioctl and implement in RAM disk block driver.
+	  This is a low level requirement for eXecute In Place (XIP) support.
+	* Add a FIOC_MMAP to perform memory mapping of a file and implemented the
+	  ioctl command in the ROMFS filesystem.  This is a requirement for eXecute
+	  In Place (XIP) support.
 
 pascal-0.1.3 2008-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
diff --git a/nuttx/drivers/lowconsole.c b/nuttx/drivers/lowconsole.c
index 743f09a0a..d627d4d87 100755
--- a/nuttx/drivers/lowconsole.c
+++ b/nuttx/drivers/lowconsole.c
@@ -82,8 +82,7 @@ struct file_operations g_serialops =
 
 static int lowconsole_ioctl(struct file *filep, int cmd, unsigned long arg)
 {
-  *get_errno_ptr() = ENOTTY;
-  return ERROR;
+  return -ENOTTY;
 }
 
 /****************************************************************************
diff --git a/nuttx/drivers/ramdisk.c b/nuttx/drivers/ramdisk.c
index 3f261943e..0bb7c1cb0 100644
--- a/nuttx/drivers/ramdisk.c
+++ b/nuttx/drivers/ramdisk.c
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <sys/types.h>
+#include <sys/ioctl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -82,6 +83,7 @@ static ssize_t rd_write(FAR struct inode *inode, const unsigned char *buffer,
                         size_t start_sector, unsigned int nsectors);
 #endif
 static int     rd_geometry(FAR struct inode *inode, struct geometry *geometry);
+static int     rd_ioctl(FAR struct inode *inode, int cmd, unsigned long arg);
 
 /****************************************************************************
  * Private Data
@@ -98,7 +100,7 @@ static const struct block_operations g_bops =
   NULL,        /* write    */
 #endif
   rd_geometry, /* geometry */
-  NULL         /* ioctl    */
+  rd_ioctl     /* ioctl    */
 };
 
 /****************************************************************************
@@ -140,18 +142,16 @@ static ssize_t rd_read(FAR struct inode *inode, unsigned char *buffer,
                        size_t start_sector, unsigned int nsectors)
 {
   struct rd_struct_s *dev;
-  if (inode)
+
+  DEBUGASSERT(inode && inode->i_private);
+  dev = (struct rd_struct_s *)inode->i_private;
+  if (start_sector < dev->rd_nsectors &&
+      start_sector + nsectors <= dev->rd_nsectors)
     {
-      dev = (struct rd_struct_s *)inode->i_private;
-      if (dev &&
-          start_sector < dev->rd_nsectors &&
-          start_sector + nsectors <= dev->rd_nsectors)
-        {
-          memcpy(buffer,
-                 &dev->rd_buffer[start_sector * dev->rd_sectsize],
-                 nsectors * dev->rd_sectsize);
-          return nsectors;
-        }
+      memcpy(buffer,
+             &dev->rd_buffer[start_sector * dev->rd_sectsize],
+             nsectors * dev->rd_sectsize);
+      return nsectors;
     }
   return -EINVAL;
 }
@@ -168,26 +168,22 @@ static ssize_t rd_write(FAR struct inode *inode, const unsigned char *buffer,
                         size_t start_sector, unsigned int nsectors)
 {
   struct rd_struct_s *dev;
-  if (inode)
+
+  DEBUGASSERT(inode && inode->i_private);
+  dev = (struct rd_struct_s *)inode->i_private;
+  if (!dev->rd_writeenabled)
     {
-      dev = (struct rd_struct_s *)inode->i_private;
-      if (dev)
-        {
-          if (!dev->rd_writeenabled)
-            {
-              return -EACCES;
-            }
-          else if (start_sector < dev->rd_nsectors &&
-                   start_sector + nsectors <= dev->rd_nsectors)
-            {
-              memcpy(&dev->rd_buffer[start_sector * dev->rd_sectsize],
-                     buffer,
-                     nsectors * dev->rd_sectsize);
-              return nsectors;
-            }
-        }
+      return -EACCES;
     }
-  return -EINVAL;
+  else if (start_sector < dev->rd_nsectors &&
+           start_sector + nsectors <= dev->rd_nsectors)
+    {
+      memcpy(&dev->rd_buffer[start_sector * dev->rd_sectsize],
+             buffer,
+             nsectors * dev->rd_sectsize);
+      return nsectors;
+    }
+  return -EFBIG;
 }
 #endif
 
@@ -201,7 +197,9 @@ static ssize_t rd_write(FAR struct inode *inode, const unsigned char *buffer,
 static int rd_geometry(FAR struct inode *inode, struct geometry *geometry)
 {
   struct rd_struct_s *dev;
-  if (inode && geometry)
+
+  DEBUGASSERT(inode);
+  if (geometry)
     {
       dev = (struct rd_struct_s *)inode->i_private;
       geometry->geo_available     = TRUE;
@@ -219,6 +217,31 @@ static int rd_geometry(FAR struct inode *inode, struct geometry *geometry)
 }
 
 /****************************************************************************
+ * Name: rd_geometry
+ *
+ * Description: Return device geometry
+ *
+ ****************************************************************************/
+
+static int rd_ioctl(FAR struct inode *inode, int cmd, unsigned long arg)
+{
+  struct rd_struct_s *dev ;
+  void **ppv = (void**)arg;
+
+  /* Only one ioctl command is supported */
+
+  DEBUGASSERT(inode && inode->i_private);
+  if (cmd == BIOC_XIPBASE && ppv)
+    {
+       dev  = (struct rd_struct_s *)inode->i_private;
+       *ppv = (void*)dev->rd_buffer;
+       return OK;
+    }
+
+  return -ENOTTY;
+}
+
+/****************************************************************************
  * Public Functions
  ****************************************************************************/
 
diff --git a/nuttx/fs/romfs/fs_romfs.c b/nuttx/fs/romfs/fs_romfs.c
index 8b1ecad09..4eb939484 100644
--- a/nuttx/fs/romfs/fs_romfs.c
+++ b/nuttx/fs/romfs/fs_romfs.c
@@ -55,6 +55,7 @@
 #include <debug.h>
 
 #include <nuttx/fs.h>
+#include <nuttx/ioctl.h>
 
 #include "fs_romfs.h"
 
@@ -71,6 +72,7 @@ static int     romfs_open(FAR struct file *filep, const char *relpath,
 static int     romfs_close(FAR struct file *filep);
 static ssize_t romfs_read(FAR struct file *filep, char *buffer, size_t buflen);
 static off_t   romfs_seek(FAR struct file *filep, off_t offset, int whence);
+static int     romfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
 
 static int     romfs_opendir(struct inode *mountpt, const char *relpath,
                            struct internal_dir_s *dir);
@@ -104,7 +106,7 @@ const struct mountpt_operations romfs_operations =
   romfs_read,      /* read */
   NULL,            /* write */
   romfs_seek,      /* seek */
-  NULL,            /* ioctl */
+  romfs_ioctl,     /* ioctl */
   NULL,            /* sync */
 
   romfs_opendir,   /* opendir */
@@ -135,7 +137,6 @@ static int romfs_open(FAR struct file *filep, const char *relpath,
                     int oflags, mode_t mode)
 {
   struct romfs_dirinfo_s  dirinfo;
-  struct inode           *inode;
   struct romfs_mountpt_s *rm;
   struct romfs_file_s    *rf;
   int                     ret;
@@ -144,12 +145,11 @@ static int romfs_open(FAR struct file *filep, const char *relpath,
 
   DEBUGASSERT(filep->f_priv == NULL && filep->f_inode != NULL);
 
-  /* Get the mountpoint inode reference from the file structure and the
-   * mountpoint private data from the inode structure
+  /* mountpoint private data from the inode reference from the file
+   * structure
    */
 
-  inode = filep->f_inode;
-  rm    = (struct romfs_mountpt_s*)inode->i_private;
+  rm = (struct romfs_mountpt_s*)filep->f_inode->i_private;
 
   DEBUGASSERT(rm != NULL);
 
@@ -211,21 +211,19 @@ static int romfs_open(FAR struct file *filep, const char *relpath,
       goto errout_with_semaphore;
     }
 
-  /* Create a file buffer to support partial sector accesses */
-
-  rf->rf_buffer = (ubyte*)malloc(rm->rm_hwsectorsize);
-  if (!rf->rf_buffer)
-    {
-      ret = -ENOMEM;
-      goto errout_with_struct;
-    }
-
   /* Initialize the file private data (only need to initialize non-zero elements) */
 
   rf->rf_open        = TRUE;
   rf->rf_startoffset = romfs_datastart(rm, dirinfo.rd_dir.fr_curroffset);
   rf->rf_size        = dirinfo.rd_size;
-  rf->rf_cachesector = (uint32)-1;
+
+  /* Confiure a buffering to support access to this file */
+
+  ret = romfs_fileconfigure(rm, rf);
+  if (ret < 0)
+    {
+      goto errout_with_semaphore;
+    }
 
   /* Attach the private date to the struct file instance */
 
@@ -243,12 +241,7 @@ static int romfs_open(FAR struct file *filep, const char *relpath,
   romfs_semgive(rm);
   return OK;
 
-  /* Error exits -- goto's are nasty things, but they sure can make error
-   * handling a lot simpler.
-   */
-
-errout_with_struct:
-  free(rf);
+  /* Error exits */
 
 errout_with_semaphore:
   romfs_semgive(rm);
@@ -261,7 +254,6 @@ errout_with_semaphore:
 
 static int romfs_close(FAR struct file *filep)
 {
-  struct inode           *inode;
   struct romfs_mountpt_s *rm;
   struct romfs_file_s    *rf;
   int                     ret = OK;
@@ -273,8 +265,7 @@ static int romfs_close(FAR struct file *filep)
   /* Recover our private data from the struct file instance */
 
   rf    = filep->f_priv;
-  inode = filep->f_inode;
-  rm    = inode->i_private;
+  rm    = filep->f_inode->i_private;
 
   DEBUGASSERT(rm != NULL);
 
@@ -289,7 +280,7 @@ static int romfs_close(FAR struct file *filep)
    * accesses.
    */
 
-  if (rf->rf_buffer)
+  if (!rm->rm_xipbase && rf->rf_buffer)
     {
       free(rf->rf_buffer);
     }
@@ -307,7 +298,6 @@ static int romfs_close(FAR struct file *filep)
 
 static ssize_t romfs_read(FAR struct file *filep, char *buffer, size_t buflen)
 {
-  struct inode           *inode;
   struct romfs_mountpt_s *rm;
   struct romfs_file_s    *rf;
   unsigned int            bytesread;
@@ -327,8 +317,7 @@ static ssize_t romfs_read(FAR struct file *filep, char *buffer, size_t buflen)
   /* Recover our private data from the struct file instance */
 
   rf    = filep->f_priv;
-  inode = filep->f_inode;
-  rm    = inode->i_private;
+  rm    = filep->f_inode->i_private;
 
   DEBUGASSERT(rm != NULL);
 
@@ -445,7 +434,6 @@ errout_with_semaphore:
 
 static off_t romfs_seek(FAR struct file *filep, off_t offset, int whence)
 {
-  struct inode           *inode;
   struct romfs_mountpt_s *rm;
   struct romfs_file_s    *rf;
   ssize_t                 position;
@@ -458,12 +446,12 @@ static off_t romfs_seek(FAR struct file *filep, off_t offset, int whence)
   /* Recover our private data from the struct file instance */
 
   rf    = filep->f_priv;
-  inode = filep->f_inode;
-  rm    = inode->i_private;
+  rm    = filep->f_inode->i_private;
 
   DEBUGASSERT(rm != NULL);
 
   /* Map the offset according to the whence option */
+
   switch (whence)
     {
     case SEEK_SET: /* The offset is set to offset bytes. */
@@ -517,9 +505,46 @@ errout_with_semaphore:
 }
 
 /****************************************************************************
+ * Name: romfs_ioctl
+ ****************************************************************************/
+
+static int romfs_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
+{
+  struct romfs_mountpt_s *rm;
+  struct romfs_file_s    *rf;
+  void **ppv = (void**)arg;
+
+  /* Sanity checks */
+
+  DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);
+
+  /* Recover our private data from the struct file instance */
+
+  rf    = filep->f_priv;
+  rm    = filep->f_inode->i_private;
+
+  DEBUGASSERT(rm != NULL);
+
+  /* Only one ioctl command is supported */
+
+  if (cmd == FIOC_MMAP && rm->rm_xipbase && ppv)
+    {
+      /* Return the address on the media corresponding to the start of
+       * the file.
+       */
+
+      *ppv = (void*)(rm->rm_xipbase + rf->rf_startoffset);
+      return OK;
+    }
+
+  return -ENOTTY;
+}
+
+/****************************************************************************
  * Name: romfs_opendir
  *
- * Description: Open a directory for read access
+ * Description:
+ *   Open a directory for read access
  *
  ****************************************************************************/
 
@@ -743,41 +768,37 @@ static int romfs_bind(FAR struct inode *blkdriver, const void *data,
 
   sem_init(&rm->rm_sem, 0, 0);     /* Initialize the semaphore that controls access */
   rm->rm_blkdriver   = blkdriver;  /* Save the block driver reference */
-  rm->rm_cachesector = (uint32)-1; /* No sector in the cache */
 
-  /* Get the hardware configuration */
+  /* Get the hardware configuration and setup buffering appropriately */
 
-  ret = romfs_getgeometry(rm);
+  ret = romfs_hwconfigure(rm);
   if (ret < 0)
     {
       goto errout_with_sem;
     }
 
-  /* Allocate the device cache buffer */
-
-  rm->rm_buffer = (ubyte*)malloc(rm->rm_hwsectorsize);
-  if (!rm->rm_buffer)
-    {
-      ret = -ENOMEM;
-      goto errout_with_sem;
-    }
-
-  /* Then complete the mount */
+  /* Then complete the mount by getting the ROMFS configuratrion from
+   * the ROMF header
+   */
 
-  ret = romfs_mount(rm);
+  ret = romfs_fsconfigure(rm);
   if (ret < 0)
     {
       goto errout_with_buffer;
     }
 
-  /* Mounted */
+  /* Mounted! */
 
   *handle = (void*)rm;
   romfs_semgive(rm);
   return OK;
 
 errout_with_buffer:
-  free(rm->rm_buffer);
+  if (!rm->rm_xipbase)
+    {
+      free(rm->rm_buffer);
+    }
+
 errout_with_sem:
   sem_destroy(&rm->rm_sem);
   free(rm);
@@ -841,7 +862,7 @@ static int romfs_unbind(void *handle, FAR struct inode **blkdriver)
 
       /* Release the mountpoint private data */
 
-      if (rm->rm_buffer)
+      if (!rm->rm_xipbase && rm->rm_buffer)
         {
           free(rm->rm_buffer);
         }
diff --git a/nuttx/fs/romfs/fs_romfs.h b/nuttx/fs/romfs/fs_romfs.h
index 607ca3f97..dd14f72e3 100644
--- a/nuttx/fs/romfs/fs_romfs.h
+++ b/nuttx/fs/romfs/fs_romfs.h
@@ -141,7 +141,8 @@ struct romfs_mountpt_s
   uint32   rm_hwnsectors;           /* HW: The number of sectors reported by the hardware */
   uint32   rm_volsize;              /* Size of the ROMFS volume */
   uint32   rm_cachesector;          /* Current sector in the rm_buffer */
-  ubyte   *rm_buffer;               /* Device sector buffer */
+  ubyte   *rm_xipbase;              /* Base address of directly accessible media */
+  ubyte   *rm_buffer;               /* Device sector buffer, allocated if rm_xipbase==0 */
 };
 
 /* This structure represents on open file under the mountpoint.  An instance
@@ -156,7 +157,7 @@ struct romfs_file_s
   uint32   rf_startoffset;          /* Offset to the start of the file data */
   uint32   rf_size;                 /* Size of the file in bytes */
   uint32   rf_cachesector;          /* Current sector in the rf_buffer */
-  ubyte   *rf_buffer;               /* File sector buffer */
+  ubyte   *rf_buffer;               /* File sector buffer, allocated if rm_xipbase==0 */
 };
 
 /* This structure is used internally for describing the result of
@@ -201,8 +202,10 @@ EXTERN int  romfs_hwread(struct romfs_mountpt_s *rm, ubyte *buffer,
 EXTERN int  romfs_devcacheread(struct romfs_mountpt_s *rm, uint32 sector);
 EXTERN int  romfs_filecacheread(struct romfs_mountpt_s *rm,
                                 struct romfs_file_s *rf, uint32 sector);
-EXTERN int  romfs_getgeometry(struct romfs_mountpt_s *rm);
-EXTERN int  romfs_mount(struct romfs_mountpt_s *rm);
+EXTERN int  romfs_hwconfigure(struct romfs_mountpt_s *rm);
+EXTERN int  romfs_fsconfigure(struct romfs_mountpt_s *rm);
+EXTERN int  romfs_fileconfigure(struct romfs_mountpt_s *rm,
+                                struct romfs_file_s *rf);
 EXTERN int  romfs_checkmount(struct romfs_mountpt_s *rm);
 EXTERN int  romfs_finddirentry(struct romfs_mountpt_s *rm,
                                struct romfs_dirinfo_s *dirinfo,
diff --git a/nuttx/fs/romfs/fs_romfsutil.c b/nuttx/fs/romfs/fs_romfsutil.c
index 7b4f43b4b..7ae274cf0 100644
--- a/nuttx/fs/romfs/fs_romfsutil.c
+++ b/nuttx/fs/romfs/fs_romfsutil.c
@@ -42,12 +42,15 @@
 #include <nuttx/config.h>
 #include <sys/types.h>
 
+#include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 #include <errno.h>
 #include <assert.h>
 #include <debug.h>
 
+#include <nuttx/ioctl.h>
+
 #include "fs_romfs.h"
 
 /****************************************************************************
@@ -298,14 +301,28 @@ void romfs_semgive(struct romfs_mountpt_s *rm)
 int romfs_hwread(struct romfs_mountpt_s *rm, ubyte *buffer, uint32 sector,
                  unsigned int nsectors)
 {
-  struct inode *inode;;
-  ssize_t nsectorsread;
   int ret = -ENODEV;
 
-  if (rm && rm->rm_blkdriver)
+  /* Check the access mode */
+
+  if (rm->rm_xipbase)
     {
-      inode = rm->rm_blkdriver;
-      if (inode && inode->u.i_bops && inode->u.i_bops->read)
+      /* In XIP mode, we just copy the requested data */
+
+      memcpy(buffer,
+             rm->rm_xipbase + sector*rm->rm_hwsectorsize,
+             nsectors*rm->rm_hwsectorsize);
+      ret = OK;
+    }
+  else
+    {
+      /* In non-XIP mode, we have to read the data from the device */
+
+      struct inode *inode = rm->rm_blkdriver;
+      ssize_t nsectorsread;
+
+      DEBUGASSERT(inode);
+      if (inode->u.i_bops && inode->u.i_bops->read)
         {
           nsectorsread =
             inode->u.i_bops->read(inode, buffer, sector, nsectors);
@@ -335,24 +352,39 @@ int romfs_devcacheread(struct romfs_mountpt_s *rm, uint32 sector)
 {
   int ret;
 
-  /* rm->rm_cachesector holds the current sector that is buffered in
-   * rm->tm_buffer. If the requested sector is the same as this sector, then
-   * we do nothing. Otherwise, we will have to read the new sector.
+  /* rm->rm_cachesector holds the current sector that is buffer in or referenced
+   * by rm->tm_buffer. If the requested sector is the same as this sector,
+   * then we do nothing.
    */
 
   if (rm->rm_cachesector != sector)
-      {
-        ret = romfs_hwread(rm, rm->rm_buffer, sector, 1);
-        if (ret < 0)
-          {
-            return ret;
-          }
+    {
+      /* Check the access mode */
+
+      if (rm->rm_xipbase)
+        {
+          /* In XIP mode, rf_buffer is just an offset pointer into the device
+           * address space.
+           */
+
+          rm->rm_buffer = rm->rm_xipbase + sector*rm->rm_hwsectorsize;
+        }
+      else
+        {
+          /* In non-XIP mode, we will have to read the new sector.*/
+
+          ret = romfs_hwread(rm, rm->rm_buffer, sector, 1);
+          if (ret < 0)
+            {
+               return ret;
+            }
+        }
 
-        /* Update the cached sector number */
+      /* Update the cached sector number */
 
-        rm->rm_cachesector = sector;
+      rm->rm_cachesector = sector;
     }
-    return OK;
+  return OK;
 }
 
 /****************************************************************************
@@ -367,35 +399,53 @@ int romfs_filecacheread(struct romfs_mountpt_s *rm, struct romfs_file_s *rf, uin
 {
   int ret;
 
-  /* rf->rf_cachesector holds the current sector that is buffered in
-   * rf->rf_buffer. If the requested sector is the same as this sector, then
-   * we do nothing. Otherwise, we will have to read the new sector.
+  /* rf->rf_cachesector holds the current sector that is buffer in or referenced
+   * by rf->rf_buffer. If the requested sector is the same as this sector,
+   * then we do nothing.
    */
 
   if (rf->rf_cachesector != sector)
-      {
-        ret = romfs_hwread(rm, rf->rf_buffer, sector, 1);
-        if (ret < 0)
-          {
-            return ret;
-          }
+    {
+      /* Check the access mode */
+
+      if (rm->rm_xipbase)
+        {
+          /* In XIP mode, rf_buffer is just an offset pointer into the device
+           * address space.
+           */
 
-        /* Update the cached sector number */
+          rf->rf_buffer = rm->rm_xipbase + sector*rm->rm_hwsectorsize;
+        }
+      else
+        {
+          /* In non-XIP mode, we will have to read the new sector.*/
 
-        rf->rf_cachesector = sector;
+          ret = romfs_hwread(rm, rf->rf_buffer, sector, 1);
+          if (ret < 0)
+            {
+              return ret;
+            }
+        }
+
+      /* Update the cached sector number */
+
+      rf->rf_cachesector = sector;
     }
-    return OK;
+  return OK;
 }
 
 /****************************************************************************
- * Name: romfs_getgeometry
+ * Name: romfs_hwconfigure
  *
  * Desciption:
- *   Get the geometry of the device (part of the mount operation)
+ *   This function is called as part of the ROMFS mount operation   It
+ *   configures the ROMFS filestem for use on this block driver.  This includes
+ *   the accounting for the geometry of the device, setting up any XIP modes
+ *   of operation, and/or allocating any cache buffers.
  *
  ****************************************************************************/
 
-int romfs_getgeometry(struct romfs_mountpt_s *rm)
+int romfs_hwconfigure(struct romfs_mountpt_s *rm)
 {
   struct inode *inode = rm->rm_blkdriver;
   struct geometry geo;
@@ -403,10 +453,12 @@ int romfs_getgeometry(struct romfs_mountpt_s *rm)
 
   /* Get the underlying device geometry */
 
+#ifdef CONFIG_DEBUG
   if (!inode || !inode->u.i_bops || !inode->u.i_bops->geometry)
     {
       return -ENODEV;
     }
+#endif
 
   ret = inode->u.i_bops->geometry(inode, &geo);
   if (ret != OK)
@@ -423,18 +475,50 @@ int romfs_getgeometry(struct romfs_mountpt_s *rm)
 
   rm->rm_hwsectorsize = geo.geo_sectorsize;
   rm->rm_hwnsectors   = geo.geo_nsectors;
+
+  /* Determine if block driver supports the XIP mode of operation */
+
+  rm->rm_cachesector  = (uint32)-1;
+
+  if (inode->u.i_bops->ioctl)
+    {
+      ret = inode->u.i_bops->ioctl(inode, BIOC_XIPBASE,
+                                   (unsigned long)&rm->rm_xipbase);
+      if (ret == OK && rm->rm_xipbase)
+        {
+          /* Yes.. Then we will directly access the media (vs.
+           * copying into an allocated sector buffer.
+           */
+
+          rm->rm_buffer      = rm->rm_xipbase;
+          rm->rm_cachesector = 0;
+          return OK;
+        }
+    }
+
+  /* Allocate the device cache buffer for normal sector accesses */
+
+  rm->rm_buffer = (ubyte*)malloc(rm->rm_hwsectorsize);
+  if (!rm->rm_buffer)
+    {
+      return -ENOMEM;
+    }
+
   return OK;
 }
 
 /****************************************************************************
- * Name: romfs_mount
+ * Name: romfs_fsconfigure
  *
  * Desciption:
- *   Setup ROMFS on the block driver
+ *   This function is called as part of the ROMFS mount operation   It
+ *   sets up the mount structure to include configuration information contained
+ *   in the ROMFS header.  This is the place where we actually determine if
+ *   the media contains a ROMFS filesystem.
  *
  ****************************************************************************/
 
-int romfs_mount(struct romfs_mountpt_s *rm)
+int romfs_fsconfigure(struct romfs_mountpt_s *rm)
 {
   const char *name;
   int ret;
@@ -472,6 +556,46 @@ int romfs_mount(struct romfs_mountpt_s *rm)
 }
 
 /****************************************************************************
+ * Name: romfs_ffileconfigure
+ *
+ * Desciption:
+ *   This function is called as part of the ROMFS file open operation   It
+ *   sets up the file structure to handle buffer appropriately, depending
+ *   upon XIP mode or not.
+ *
+ ****************************************************************************/
+
+int romfs_fileconfigure(struct romfs_mountpt_s *rm, struct romfs_file_s *rf)
+{
+  /* Check if XIP access mode is supported.  If so, then we do not need
+   * to allocate anything.
+   */
+
+  if (rm->rm_xipbase)
+    {
+      /* We'll put a valid address in rf_buffer just in case. */
+
+      rf->rf_cachesector = 0;
+      rf->rf_buffer      = rm->rm_xipbase  + rf->rf_startoffset;
+    }
+  else
+    {
+      /* Nothing in the cache buffer */
+
+      rf->rf_cachesector = (uint32)-1;
+
+      /* Create a file buffer to support partial sector accesses */
+
+      rf->rf_buffer = (ubyte*)malloc(rm->rm_hwsectorsize);
+      if (!rf->rf_buffer)
+        {
+          return -ENOMEM;
+        }
+    }
+  return OK;
+}
+
+/****************************************************************************
  * Name: romfs_checkmount
  *
  * Desciption: Check if the mountpoint is still valid.
@@ -482,29 +606,29 @@ int romfs_mount(struct romfs_mountpt_s *rm)
 
 int romfs_checkmount(struct romfs_mountpt_s *rm)
 {
+  struct romfs_file_s *file;
+  struct inode *inode;
+  struct geometry geo;
+  int ret;
+
   /* If the fs_mounted flag is FALSE, then we have already handled the loss
    * of the mount.
    */
 
-  if (rm && rm->rm_mounted)
+  DEBUGASSERT(rm && rm->rm_blkdriver);
+  if (rm->rm_mounted)
     {
-      struct romfs_file_s *file;
-
       /* We still think the mount is healthy.  Check an see if this is
        * still the case
        */
 
-      if (rm->rm_blkdriver)
+      inode = rm->rm_blkdriver;
+      if (inode->u.i_bops && inode->u.i_bops->geometry)
         {
-          struct inode *inode = rm->rm_blkdriver;
-          if (inode && inode->u.i_bops && inode->u.i_bops->geometry)
+          ret = inode->u.i_bops->geometry(inode, &geo);
+          if (ret == OK && geo.geo_available && !geo.geo_mediachanged)
             {
-              struct geometry geo;
-              int errcode = inode->u.i_bops->geometry(inode, &geo);
-              if (errcode == OK && geo.geo_available && !geo.geo_mediachanged)
-                {
-                  return OK;
-                }
+              return OK;
             }
         }
 
diff --git a/nuttx/include/nuttx/ioctl.h b/nuttx/include/nuttx/ioctl.h
index a61d1108d..6ebfce997 100644
--- a/nuttx/include/nuttx/ioctl.h
+++ b/nuttx/include/nuttx/ioctl.h
@@ -52,6 +52,7 @@
  * defined below:
  */
 
+#define _FIOCBASE       (0x8700) /* File system ioctl commands */
 #define _BIOCBASE       (0x8800) /* Block driver ioctl commands */
 #define _SIOCBASE       (0x8900) /* Socket ioctl commandss */
 
@@ -63,14 +64,25 @@
 
 #define _IOC(type,nr)   ((type)|(nr))
 
+/* NuttX file system ioctl definitions */
+
+#define _FIOCVALID(c)   (_IOC_TYPE(c)==_FIOCBASE)
+#define _FIOC(nr)       _IOC(_FIOCBASE,nr)
+
+#define FIOC_MMAP       _FIOC(0x0001)  /* IN:  None
+                                        * OUT: If media is directly acccesible,
+                                        *      return (void*) base address
+                                        *      of file */
+
 /* NuttX block driver ioctl definitions */
 
 #define _BIOCVALID(c)   (_IOC_TYPE(c)==_BIOCBASE)
-#define _BIOC(nr)       _IOC(_SIOCBASE,nr)
+#define _BIOC(nr)       _IOC(_BIOCBASE,nr)
 
-#define _BIOC_XIPBASE _BIOC(0x0001)  /* IN:  None
-                                      * OUT: If underlying is random acccesible,
-                                      *      return (void*) base address */
+#define BIOC_XIPBASE    _BIOC(0x0001)  /* IN:  None
+                                        * OUT: If media is directly acccesible,
+                                        *      return (void*) base address
+                                        *      of device memory */
 
 /****************************************************************************
  * Public Type Definitions