Include/mpu_armv7.h

/******************************************************************************
 * @file     mpu_armv7.h
 * @brief    CMSIS MPU API for Armv7-M MPU
 * @version  V5.0.4
 * @date     10. January 2018
 ******************************************************************************/
/*
 * Copyright (c) 2017-2018 Arm Limited. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the License); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#if   defined ( __ICCARM__ )
  #pragma system_include         /* treat file as system include file for MISRA check */
#elif defined (__clang__)
  #pragma clang system_header    /* treat file as system include file */
#endif
 
#ifndef ARM_MPU_ARMV7_H
#define ARM_MPU_ARMV7_H

#define ARM_MPU_REGION_SIZE_32B      ((uint8_t)0x04U) ///!< MPU Region Size 32 Bytes
#define ARM_MPU_REGION_SIZE_64B      ((uint8_t)0x05U) ///!< MPU Region Size 64 Bytes
#define ARM_MPU_REGION_SIZE_128B     ((uint8_t)0x06U) ///!< MPU Region Size 128 Bytes
#define ARM_MPU_REGION_SIZE_256B     ((uint8_t)0x07U) ///!< MPU Region Size 256 Bytes
#define ARM_MPU_REGION_SIZE_512B     ((uint8_t)0x08U) ///!< MPU Region Size 512 Bytes
#define ARM_MPU_REGION_SIZE_1KB      ((uint8_t)0x09U) ///!< MPU Region Size 1 KByte
#define ARM_MPU_REGION_SIZE_2KB      ((uint8_t)0x0AU) ///!< MPU Region Size 2 KBytes
#define ARM_MPU_REGION_SIZE_4KB      ((uint8_t)0x0BU) ///!< MPU Region Size 4 KBytes
#define ARM_MPU_REGION_SIZE_8KB      ((uint8_t)0x0CU) ///!< MPU Region Size 8 KBytes
#define ARM_MPU_REGION_SIZE_16KB     ((uint8_t)0x0DU) ///!< MPU Region Size 16 KBytes
#define ARM_MPU_REGION_SIZE_32KB     ((uint8_t)0x0EU) ///!< MPU Region Size 32 KBytes
#define ARM_MPU_REGION_SIZE_64KB     ((uint8_t)0x0FU) ///!< MPU Region Size 64 KBytes
#define ARM_MPU_REGION_SIZE_128KB    ((uint8_t)0x10U) ///!< MPU Region Size 128 KBytes
#define ARM_MPU_REGION_SIZE_256KB    ((uint8_t)0x11U) ///!< MPU Region Size 256 KBytes
#define ARM_MPU_REGION_SIZE_512KB    ((uint8_t)0x12U) ///!< MPU Region Size 512 KBytes
#define ARM_MPU_REGION_SIZE_1MB      ((uint8_t)0x13U) ///!< MPU Region Size 1 MByte
#define ARM_MPU_REGION_SIZE_2MB      ((uint8_t)0x14U) ///!< MPU Region Size 2 MBytes
#define ARM_MPU_REGION_SIZE_4MB      ((uint8_t)0x15U) ///!< MPU Region Size 4 MBytes
#define ARM_MPU_REGION_SIZE_8MB      ((uint8_t)0x16U) ///!< MPU Region Size 8 MBytes
#define ARM_MPU_REGION_SIZE_16MB     ((uint8_t)0x17U) ///!< MPU Region Size 16 MBytes
#define ARM_MPU_REGION_SIZE_32MB     ((uint8_t)0x18U) ///!< MPU Region Size 32 MBytes
#define ARM_MPU_REGION_SIZE_64MB     ((uint8_t)0x19U) ///!< MPU Region Size 64 MBytes
#define ARM_MPU_REGION_SIZE_128MB    ((uint8_t)0x1AU) ///!< MPU Region Size 128 MBytes
#define ARM_MPU_REGION_SIZE_256MB    ((uint8_t)0x1BU) ///!< MPU Region Size 256 MBytes
#define ARM_MPU_REGION_SIZE_512MB    ((uint8_t)0x1CU) ///!< MPU Region Size 512 MBytes
#define ARM_MPU_REGION_SIZE_1GB      ((uint8_t)0x1DU) ///!< MPU Region Size 1 GByte
#define ARM_MPU_REGION_SIZE_2GB      ((uint8_t)0x1EU) ///!< MPU Region Size 2 GBytes
#define ARM_MPU_REGION_SIZE_4GB      ((uint8_t)0x1FU) ///!< MPU Region Size 4 GBytes

#define ARM_MPU_AP_NONE 0U ///!< MPU Access Permission no access
#define ARM_MPU_AP_PRIV 1U ///!< MPU Access Permission privileged access only
#define ARM_MPU_AP_URO  2U ///!< MPU Access Permission unprivileged access read-only
#define ARM_MPU_AP_FULL 3U ///!< MPU Access Permission full access
#define ARM_MPU_AP_PRO  5U ///!< MPU Access Permission privileged access read-only
#define ARM_MPU_AP_RO   6U ///!< MPU Access Permission read-only access

/** MPU Region Base Address Register Value
*
* \param Region The region to be configured, number 0 to 15.
* \param BaseAddress The base address for the region.
*/
#define ARM_MPU_RBAR(Region, BaseAddress) \
  (((BaseAddress) & MPU_RBAR_ADDR_Msk) |  \
   ((Region) & MPU_RBAR_REGION_Msk)    |  \
   (MPU_RBAR_VALID_Msk))

/**
* MPU Memory Access Attributes
* 
* \param TypeExtField      Type extension field, allows you to configure memory access type, for example strongly ordered, peripheral.
* \param IsShareable       Region is shareable between multiple bus masters.
* \param IsCacheable       Region is cacheable, i.e. its value may be kept in cache.
* \param IsBufferable      Region is bufferable, i.e. using write-back caching. Cacheable but non-bufferable regions use write-through policy.
*/  
#define ARM_MPU_ACCESS_(TypeExtField, IsShareable, IsCacheable, IsBufferable)   \
  ((((TypeExtField ) << MPU_RASR_TEX_Pos) & MPU_RASR_TEX_Msk)                 | \
   (((IsShareable ) << MPU_RASR_S_Pos) & MPU_RASR_S_Msk)                      | \
   (((IsCacheable ) << MPU_RASR_C_Pos) & MPU_RASR_C_Msk)                      | \
   (((IsBufferable ) << MPU_RASR_B_Pos) & MPU_RASR_B_Msk))

/**
* MPU Region Attribute and Size Register Value
* 
* \param DisableExec       Instruction access disable bit, 1= disable instruction fetches.
* \param AccessPermission  Data access permissions, allows you to configure read/write access for User and Privileged mode.
* \param AccessAttributes  Memory access attribution, see \ref ARM_MPU_ACCESS_.
* \param SubRegionDisable  Sub-region disable field.
* \param Size              Region size of the region to be configured, for example 4K, 8K.
*/
#define ARM_MPU_RASR_EX(DisableExec, AccessPermission, AccessAttributes, SubRegionDisable, Size)      \
  ((((DisableExec ) << MPU_RASR_XN_Pos) & MPU_RASR_XN_Msk)                                          | \
   (((AccessPermission) << MPU_RASR_AP_Pos) & MPU_RASR_AP_Msk)                                      | \
   (((AccessAttributes) ) & (MPU_RASR_TEX_Msk | MPU_RASR_S_Msk | MPU_RASR_C_Msk | MPU_RASR_B_Msk)))
  
/**
* MPU Region Attribute and Size Register Value
* 
* \param DisableExec       Instruction access disable bit, 1= disable instruction fetches.
* \param AccessPermission  Data access permissions, allows you to configure read/write access for User and Privileged mode.
* \param TypeExtField      Type extension field, allows you to configure memory access type, for example strongly ordered, peripheral.
* \param IsShareable       Region is shareable between multiple bus masters.
* \param IsCacheable       Region is cacheable, i.e. its value may be kept in cache.
* \param IsBufferable      Region is bufferable, i.e. using write-back caching. Cacheable but non-bufferable regions use write-through policy.
* \param SubRegionDisable  Sub-region disable field.
* \param Size              Region size of the region to be configured, for example 4K, 8K.
*/                         
#define ARM_MPU_RASR(DisableExec, AccessPermission, TypeExtField, IsShareable, IsCacheable, IsBufferable, SubRegionDisable, Size) \
  ARM_MPU_RASR_EX(DisableExec, AccessPermission, ARM_MPU_ACCESS_(TypeExtField, IsShareable, IsCacheable, IsBufferable), SubRegionDisable, Size)

/**
* MPU Memory Access Attribute for strongly ordered memory.
*  - TEX: 000b
*  - Shareable
*  - Non-cacheable
*  - Non-bufferable
*/ 
#define ARM_MPU_ACCESS_ORDERED ARM_MPU_ACCESS_(0U, 1U, 0U, 0U)

/**
* MPU Memory Access Attribute for device memory.
*  - TEX: 000b (if non-shareable) or 010b (if shareable)
*  - Shareable or non-shareable
*  - Non-cacheable
*  - Bufferable (if shareable) or non-bufferable (if non-shareable)
*
* \param IsShareable Configures the device memory as shareable or non-shareable.
*/ 
#define ARM_MPU_ACCESS_DEVICE(IsShareable) ((IsShareable) ? ARM_MPU_ACCESS_(0U, 1U, 0U, 1U) : ARM_MPU_ACCESS_(2U, 0U, 0U, 0U))

/**
* MPU Memory Access Attribute for normal memory.
*  - TEX: 1BBb (reflecting outer cacheability rules)
*  - Shareable or non-shareable
*  - Cacheable or non-cacheable (reflecting inner cacheability rules)
*  - Bufferable or non-bufferable (reflecting inner cacheability rules)
*
* \param OuterCp Configures the outer cache policy.
* \param InnerCp Configures the inner cache policy.
* \param IsShareable Configures the memory as shareable or non-shareable.
*/ 
#define ARM_MPU_ACCESS_NORMAL(OuterCp, InnerCp, IsShareable) ARM_MPU_ACCESS_((4U | (OuterCp)), IsShareable, ((InnerCp) & 2U), ((InnerCp) & 1U))

/**
* MPU Memory Access Attribute non-cacheable policy.
*/
#define ARM_MPU_CACHEP_NOCACHE 0U

/**
* MPU Memory Access Attribute write-back, write and read allocate policy.
*/
#define ARM_MPU_CACHEP_WB_WRA 1U

/**
* MPU Memory Access Attribute write-through, no write allocate policy.
*/
#define ARM_MPU_CACHEP_WT_NWA 2U

/**
* MPU Memory Access Attribute write-back, no write allocate policy.
*/
#define ARM_MPU_CACHEP_WB_NWA 3U


/**
* Struct for a single MPU Region
*/
typedef struct {
  uint32_t RBAR; //!< The region base address register value (RBAR)
  uint32_t RASR; //!< The region attribute and size register value (RASR) \ref MPU_RASR
} ARM_MPU_Region_t;
    
/** Enable the MPU.
* \param MPU_Control Default access permissions for unconfigured regions.
*/
__STATIC_INLINE void ARM_MPU_Enable(uint32_t MPU_Control)
{
  __DSB();
  __ISB();
  MPU->CTRL = MPU_Control | MPU_CTRL_ENABLE_Msk;
#ifdef SCB_SHCSR_MEMFAULTENA_Msk
  SCB->SHCSR |= SCB_SHCSR_MEMFAULTENA_Msk;
#endif
}

/** Disable the MPU.
*/
__STATIC_INLINE void ARM_MPU_Disable(void)
{
  __DSB();
  __ISB();
#ifdef SCB_SHCSR_MEMFAULTENA_Msk
  SCB->SHCSR &= ~SCB_SHCSR_MEMFAULTENA_Msk;
#endif
  MPU->CTRL  &= ~MPU_CTRL_ENABLE_Msk;
}

/** Clear and disable the given MPU region.
* \param rnr Region number to be cleared.
*/
__STATIC_INLINE void ARM_MPU_ClrRegion(uint32_t rnr)
{
  MPU->RNR = rnr;
  MPU->RASR = 0U;
}

/** Configure an MPU region.
* \param rbar Value for RBAR register.
* \param rsar Value for RSAR register.
*/   
__STATIC_INLINE void ARM_MPU_SetRegion(uint32_t rbar, uint32_t rasr)
{
  MPU->RBAR = rbar;
  MPU->RASR = rasr;
}

/** Configure the given MPU region.
* \param rnr Region number to be configured.
* \param rbar Value for RBAR register.
* \param rsar Value for RSAR register.
*/   
__STATIC_INLINE void ARM_MPU_SetRegionEx(uint32_t rnr, uint32_t rbar, uint32_t rasr)
{
  MPU->RNR = rnr;
  MPU->RBAR = rbar;
  MPU->RASR = rasr;
}

/** Memcopy with strictly ordered memory access, e.g. for register targets.
* \param dst Destination data is copied to.
* \param src Source data is copied from.
* \param len Amount of data words to be copied.
*/
__STATIC_INLINE void orderedCpy(volatile uint32_t* dst, const uint32_t* __RESTRICT src, uint32_t len)
{
  uint32_t i;
  for (i = 0U; i < len; ++i) 
  {
    dst[i] = src[i];
  }
}

/** Load the given number of MPU regions from a table.
* \param table Pointer to the MPU configuration table.
* \param cnt Amount of regions to be configured.
*/
__STATIC_INLINE void ARM_MPU_Load(ARM_MPU_Region_t const* table, uint32_t cnt) 
{
  const uint32_t rowWordSize = sizeof(ARM_MPU_Region_t)/4U;
  while (cnt > MPU_TYPE_RALIASES) {
    orderedCpy(&(MPU->RBAR), &(table->RBAR), MPU_TYPE_RALIASES*rowWordSize);
    table += MPU_TYPE_RALIASES;
    cnt -= MPU_TYPE_RALIASES;
  }
  orderedCpy(&(MPU->RBAR), &(table->RBAR), cnt*rowWordSize);
}

#endif