circuitpython/lib/cmsis/inc/mpu_armv8.h

/******************************************************************************
 * @file     mpu_armv8.h
 * @brief    CMSIS MPU API for Armv8-M and Armv8.1-M MPU
 * @version  V5.1.0
 * @date     08. March 2019
 ******************************************************************************/
/*
 * Copyright (c) 2017-2019 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_ARMV8_H
#define ARM_MPU_ARMV8_H

/** \brief Attribute for device memory (outer only) */
#define ARM_MPU_ATTR_DEVICE                           ( 0U )

/** \brief Attribute for non-cacheable, normal memory */
#define ARM_MPU_ATTR_NON_CACHEABLE                    ( 4U )

/** \brief Attribute for normal memory (outer and inner)
* \param NT Non-Transient: Set to 1 for non-transient data.
* \param WB Write-Back: Set to 1 to use write-back update policy.
* \param RA Read Allocation: Set to 1 to use cache allocation on read miss.
* \param WA Write Allocation: Set to 1 to use cache allocation on write miss.
*/
#define ARM_MPU_ATTR_MEMORY_(NT, WB, RA, WA) \
  (((NT & 1U) << 3U) | ((WB & 1U) << 2U) | ((RA & 1U) << 1U) | (WA & 1U))

/** \brief Device memory type non Gathering, non Re-ordering, non Early Write Acknowledgement */
#define ARM_MPU_ATTR_DEVICE_nGnRnE (0U)

/** \brief Device memory type non Gathering, non Re-ordering, Early Write Acknowledgement */
#define ARM_MPU_ATTR_DEVICE_nGnRE  (1U)

/** \brief Device memory type non Gathering, Re-ordering, Early Write Acknowledgement */
#define ARM_MPU_ATTR_DEVICE_nGRE   (2U)

/** \brief Device memory type Gathering, Re-ordering, Early Write Acknowledgement */
#define ARM_MPU_ATTR_DEVICE_GRE    (3U)

/** \brief Memory Attribute
* \param O Outer memory attributes
* \param I O == ARM_MPU_ATTR_DEVICE: Device memory attributes, else: Inner memory attributes
*/
#define ARM_MPU_ATTR(O, I) (((O & 0xFU) << 4U) | (((O & 0xFU) != 0U) ? (I & 0xFU) : ((I & 0x3U) << 2U)))

/** \brief Normal memory non-shareable  */
#define ARM_MPU_SH_NON   (0U)

/** \brief Normal memory outer shareable  */
#define ARM_MPU_SH_OUTER (2U)

/** \brief Normal memory inner shareable  */
#define ARM_MPU_SH_INNER (3U)

/** \brief Memory access permissions
* \param RO Read-Only: Set to 1 for read-only memory.
* \param NP Non-Privileged: Set to 1 for non-privileged memory.
*/
#define ARM_MPU_AP_(RO, NP) (((RO & 1U) << 1U) | (NP & 1U))

/** \brief Region Base Address Register value
* \param BASE The base address bits [31:5] of a memory region. The value is zero extended. Effective address gets 32 byte aligned.
* \param SH Defines the Shareability domain for this memory region.
* \param RO Read-Only: Set to 1 for a read-only memory region.
* \param NP Non-Privileged: Set to 1 for a non-privileged memory region.
* \oaram XN eXecute Never: Set to 1 for a non-executable memory region.
*/
#define ARM_MPU_RBAR(BASE, SH, RO, NP, XN) \
  ((BASE & MPU_RBAR_BASE_Msk) | \
  ((SH << MPU_RBAR_SH_Pos) & MPU_RBAR_SH_Msk) | \
  ((ARM_MPU_AP_(RO, NP) << MPU_RBAR_AP_Pos) & MPU_RBAR_AP_Msk) | \
  ((XN << MPU_RBAR_XN_Pos) & MPU_RBAR_XN_Msk))

/** \brief Region Limit Address Register value
* \param LIMIT The limit address bits [31:5] for this memory region. The value is one extended.
* \param IDX The attribute index to be associated with this memory region.
*/
#define ARM_MPU_RLAR(LIMIT, IDX) \
  ((LIMIT & MPU_RLAR_LIMIT_Msk) | \
  ((IDX << MPU_RLAR_AttrIndx_Pos) & MPU_RLAR_AttrIndx_Msk) | \
  (MPU_RLAR_EN_Msk))

#if defined(MPU_RLAR_PXN_Pos)

/** \brief Region Limit Address Register with PXN value
* \param LIMIT The limit address bits [31:5] for this memory region. The value is one extended.
* \param PXN Privileged execute never. Defines whether code can be executed from this privileged region.
* \param IDX The attribute index to be associated with this memory region.
*/
#define ARM_MPU_RLAR_PXN(LIMIT, PXN, IDX) \
  ((LIMIT & MPU_RLAR_LIMIT_Msk) | \
  ((PXN << MPU_RLAR_PXN_Pos) & MPU_RLAR_PXN_Msk) | \
  ((IDX << MPU_RLAR_AttrIndx_Pos) & MPU_RLAR_AttrIndx_Msk) | \
  (MPU_RLAR_EN_Msk))

#endif

/**
* Struct for a single MPU Region
*/
typedef struct {
  uint32_t RBAR;                   /*!< Region Base Address Register value */
  uint32_t RLAR;                   /*!< Region Limit Address Register value */
} 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)
{
  MPU->CTRL = MPU_Control | MPU_CTRL_ENABLE_Msk;
#ifdef SCB_SHCSR_MEMFAULTENA_Msk
  SCB->SHCSR |= SCB_SHCSR_MEMFAULTENA_Msk;
#endif
  __DSB();
  __ISB();
}

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

#ifdef MPU_NS
/** Enable the Non-secure MPU.
* \param MPU_Control Default access permissions for unconfigured regions.
*/
__STATIC_INLINE void ARM_MPU_Enable_NS(uint32_t MPU_Control)
{
  MPU_NS->CTRL = MPU_Control | MPU_CTRL_ENABLE_Msk;
#ifdef SCB_SHCSR_MEMFAULTENA_Msk
  SCB_NS->SHCSR |= SCB_SHCSR_MEMFAULTENA_Msk;
#endif
  __DSB();
  __ISB();
}

/** Disable the Non-secure MPU.
*/
__STATIC_INLINE void ARM_MPU_Disable_NS(void)
{
  __DMB();
#ifdef SCB_SHCSR_MEMFAULTENA_Msk
  SCB_NS->SHCSR &= ~SCB_SHCSR_MEMFAULTENA_Msk;
#endif
  MPU_NS->CTRL  &= ~MPU_CTRL_ENABLE_Msk;
}
#endif

/** Set the memory attribute encoding to the given MPU.
* \param mpu Pointer to the MPU to be configured.
* \param idx The attribute index to be set [0-7]
* \param attr The attribute value to be set.
*/
__STATIC_INLINE void ARM_MPU_SetMemAttrEx(MPU_Type* mpu, uint8_t idx, uint8_t attr)
{
  const uint8_t reg = idx / 4U;
  const uint32_t pos = ((idx % 4U) * 8U);
  const uint32_t mask = 0xFFU << pos;

  if (reg >= (sizeof(mpu->MAIR) / sizeof(mpu->MAIR[0]))) {
    return; // invalid index
  }

  mpu->MAIR[reg] = ((mpu->MAIR[reg] & ~mask) | ((attr << pos) & mask));
}

/** Set the memory attribute encoding.
* \param idx The attribute index to be set [0-7]
* \param attr The attribute value to be set.
*/
__STATIC_INLINE void ARM_MPU_SetMemAttr(uint8_t idx, uint8_t attr)
{
  ARM_MPU_SetMemAttrEx(MPU, idx, attr);
}

#ifdef MPU_NS
/** Set the memory attribute encoding to the Non-secure MPU.
* \param idx The attribute index to be set [0-7]
* \param attr The attribute value to be set.
*/
__STATIC_INLINE void ARM_MPU_SetMemAttr_NS(uint8_t idx, uint8_t attr)
{
  ARM_MPU_SetMemAttrEx(MPU_NS, idx, attr);
}
#endif

/** Clear and disable the given MPU region of the given MPU.
* \param mpu Pointer to MPU to be used.
* \param rnr Region number to be cleared.
*/
__STATIC_INLINE void ARM_MPU_ClrRegionEx(MPU_Type* mpu, uint32_t rnr)
{
  mpu->RNR = rnr;
  mpu->RLAR = 0U;
}

/** Clear and disable the given MPU region.
* \param rnr Region number to be cleared.
*/
__STATIC_INLINE void ARM_MPU_ClrRegion(uint32_t rnr)
{
  ARM_MPU_ClrRegionEx(MPU, rnr);
}

#ifdef MPU_NS
/** Clear and disable the given Non-secure MPU region.
* \param rnr Region number to be cleared.
*/
__STATIC_INLINE void ARM_MPU_ClrRegion_NS(uint32_t rnr)
{
  ARM_MPU_ClrRegionEx(MPU_NS, rnr);
}
#endif

/** Configure the given MPU region of the given MPU.
* \param mpu Pointer to MPU to be used.
* \param rnr Region number to be configured.
* \param rbar Value for RBAR register.
* \param rlar Value for RLAR register.
*/
__STATIC_INLINE void ARM_MPU_SetRegionEx(MPU_Type* mpu, uint32_t rnr, uint32_t rbar, uint32_t rlar)
{
  mpu->RNR = rnr;
  mpu->RBAR = rbar;
  mpu->RLAR = rlar;
}

/** Configure the given MPU region.
* \param rnr Region number to be configured.
* \param rbar Value for RBAR register.
* \param rlar Value for RLAR register.
*/
__STATIC_INLINE void ARM_MPU_SetRegion(uint32_t rnr, uint32_t rbar, uint32_t rlar)
{
  ARM_MPU_SetRegionEx(MPU, rnr, rbar, rlar);
}

#ifdef MPU_NS
/** Configure the given Non-secure MPU region.
* \param rnr Region number to be configured.
* \param rbar Value for RBAR register.
* \param rlar Value for RLAR register.
*/
__STATIC_INLINE void ARM_MPU_SetRegion_NS(uint32_t rnr, uint32_t rbar, uint32_t rlar)
{
  ARM_MPU_SetRegionEx(MPU_NS, rnr, rbar, rlar);
}
#endif

/** 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 ARM_MPU_OrderedMemcpy(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 to the given MPU.
* \param mpu Pointer to the MPU registers to be used.
* \param rnr First region number to be configured.
* \param table Pointer to the MPU configuration table.
* \param cnt Amount of regions to be configured.
*/
__STATIC_INLINE void ARM_MPU_LoadEx(MPU_Type* mpu, uint32_t rnr, ARM_MPU_Region_t const* table, uint32_t cnt)
{
  const uint32_t rowWordSize = sizeof(ARM_MPU_Region_t)/4U;
  if (cnt == 1U) {
    mpu->RNR = rnr;
    ARM_MPU_OrderedMemcpy(&(mpu->RBAR), &(table->RBAR), rowWordSize);
  } else {
    uint32_t rnrBase   = rnr & ~(MPU_TYPE_RALIASES-1U);
    uint32_t rnrOffset = rnr % MPU_TYPE_RALIASES;

    mpu->RNR = rnrBase;
    while ((rnrOffset + cnt) > MPU_TYPE_RALIASES) {
      uint32_t c = MPU_TYPE_RALIASES - rnrOffset;
      ARM_MPU_OrderedMemcpy(&(mpu->RBAR)+(rnrOffset*2U), &(table->RBAR), c*rowWordSize);
      table += c;
      cnt -= c;
      rnrOffset = 0U;
      rnrBase += MPU_TYPE_RALIASES;
      mpu->RNR = rnrBase;
    }

    ARM_MPU_OrderedMemcpy(&(mpu->RBAR)+(rnrOffset*2U), &(table->RBAR), cnt*rowWordSize);
  }
}

/** Load the given number of MPU regions from a table.
* \param rnr First region number to be configured.
* \param table Pointer to the MPU configuration table.
* \param cnt Amount of regions to be configured.
*/
__STATIC_INLINE void ARM_MPU_Load(uint32_t rnr, ARM_MPU_Region_t const* table, uint32_t cnt)
{
  ARM_MPU_LoadEx(MPU, rnr, table, cnt);
}

#ifdef MPU_NS
/** Load the given number of MPU regions from a table to the Non-secure MPU.
* \param rnr First region number to be configured.
* \param table Pointer to the MPU configuration table.
* \param cnt Amount of regions to be configured.
*/
__STATIC_INLINE void ARM_MPU_Load_NS(uint32_t rnr, ARM_MPU_Region_t const* table, uint32_t cnt)
{
  ARM_MPU_LoadEx(MPU_NS, rnr, table, cnt);
}
#endif

#endif