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/****************************************************************************
* arch/arm/src/common/sam3u_mpuinit.c
*
* Copyright (C) 2011 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 <assert.h>
#include <arch/board/user_map.h>
#include "mpu.h"
#ifdef CONFIG_NUTTX_KERNEL
/****************************************************************************
* Private Definitions
****************************************************************************/
#ifndef MAX
# define MAX(a,b) a > b ? a : b
#endif
#ifndef MIN
# define MIN(a,b) a < b ? a : b
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sam3u_mpuinitialize
*
* Description:
* Configure the MPU to permit user-space access to only restricted SAM3U
* resources.
*
****************************************************************************/
void sam3u_mpuinitialize(void)
{
uintptr_t datastart = MIN(CONFIG_USER_DATADESTSTART, CONFIG_USER_BSSSTART);
uintptr_t dataend = MAX(CONFIG_USER_DATADESTEND, CONFIG_USER_BSSEND);
DEBUGASSERT(CONFIG_USER_TEXTEND >= CONFIG_USER_TEXTSTART && dataend >= datastart);
/* Show MPU information */
mpu_showtype();
/* Configure user flash and SRAM space */
mpu_userflash(CONFIG_USER_TEXTSTART, CONFIG_USER_TEXTEND - CONFIG_USER_TEXTSTART);
mpu_userintsram(datastart, dataend - datastart);
/* Then enable the MPU */
mpu_control(true, false, true);
}
/****************************************************************************
* Name: sam3u_mpuheap
*
* Description:
* Map a heap region (probably needs to extension to handle external SRAM).
*
****************************************************************************/
void sam3u_mpuheap(uintptr_t start, size_t size)
{
mpu_userintsram(start, size);
}
#endif /* CONFIG_NUTTX_KERNEL */
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