/****************************************************************************
 * arch/arm/src/armv7-a/arm_virtpgaddr.c
 *
 *   Copyright (C) 2014 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 "pgalloc.h"

#if defined(CONFIG_MM_PGALLOC) && defined(CONFIG_ARCH_PGPOOL_MAPPING)

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Data
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: arm_virtpgaddr
 *
 * Description:
 *   Check if the physical address lies in the page pool and, if so
 *   get the mapping to the virtual address in the user data area.
 *
 ****************************************************************************/

uintptr_t arm_virtpgaddr(uintptr_t paddr)
{
  /* REVISIT: Not implemented correctly.  The reverse lookup from physical
   * to virtual.  This will return a kernel accessible virtual address, but
   * not an address usable by the user code.
   *
   * The correct solutions is complex and, perhaps, will never be needed.
   */

  if (paddr >= CONFIG_ARCH_PGPOOL_PBASE && paddr < CONFIG_ARCH_PGPOOL_PEND)
    {
      return paddr - CONFIG_ARCH_PGPOOL_PBASE + CONFIG_ARCH_PGPOOL_VBASE;
    }

  return 0;
}

#endif /* CONFIG_MM_PGALLOC && CONFIG_ARCH_PGPOOL_MAPPING */
