/****************************************************************************
* arch/arm/src/common/sam_mpuinit.c
*
* Copyright (C) 2011, 2013 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 <nuttx/userspace.h>
#include "mpu.h"
#include "sam_mpuinit.h"
#if defined(CONFIG_BUILD_PROTECTED) && defined(CONFIG_ARMV7M_MPU)
/****************************************************************************
* 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: sam_mpuinitialize
*
* Description:
* Configure the MPU to permit user-space access to only restricted SAM3/4
* resources.
*
****************************************************************************/
void sam_mpuinitialize(void)
{
uintptr_t datastart = MIN(USERSPACE->us_datastart, USERSPACE->us_bssstart);
uintptr_t dataend = MAX(USERSPACE->us_dataend, USERSPACE->us_bssend);
DEBUGASSERT(USERSPACE->us_textend >= USERSPACE->us_textstart &&
dataend >= datastart);
/* Show MPU information */
mpu_showtype();
/* Configure user flash and SRAM space */
mpu_userflash(USERSPACE->us_textstart,
USERSPACE->us_textend - USERSPACE->us_textstart);
mpu_userintsram(datastart, dataend - datastart);
/* Then enable the MPU */
mpu_control(true, false, true);
}
/****************************************************************************
* Name: sam_mpu_uheap
*
* Description:
* Map the user-heap region.
*
* This logic may need an extension to handle external SDRAM).
*
****************************************************************************/
void sam_mpu_uheap(uintptr_t start, size_t size)
{
mpu_userintsram(start, size);
}
#endif /* CONFIG_BUILD_PROTECTED && CONFIG_ARMV7M_MPU */
