| /* Copyright 2018 SiFive, Inc */ |
| /* SPDX-License-Identifier: Apache-2.0 */ |
| |
| #ifndef METAL__PMP_H |
| #define METAL__PMP_H |
| |
| /*! |
| * @file metal/pmp.h |
| * |
| * @brief API for Configuring Physical Memory Protection on RISC-V Cores |
| * |
| * The Physical Memory Protection (PMP) interface on RISC-V cores |
| * is a form of memory protection unit which allows for a finite number |
| * of physical memory regions to be configured with certain access |
| * permissions. |
| * |
| * Additional information about the use and configuration rules for PMPs |
| * can be found by reading the RISC-V Privileged Architecture Specification. |
| */ |
| |
| #include <stddef.h> |
| #include <metal/machine.h> |
| |
| struct metal_pmp; |
| |
| /*! |
| * @brief Set of available PMP addressing modes |
| */ |
| enum metal_pmp_address_mode { |
| /*! @brief Disable the PMP region */ |
| METAL_PMP_OFF = 0, |
| /*! @brief Use Top-of-Range mode */ |
| METAL_PMP_TOR = 1, |
| /*! @brief Use naturally-aligned 4-byte region mode */ |
| METAL_PMP_NA4 = 2, |
| /*! @brief Use naturally-aligned power-of-two mode */ |
| METAL_PMP_NAPOT = 3 |
| }; |
| |
| /*! |
| * @brief Configuration for a PMP region |
| */ |
| struct metal_pmp_config { |
| /*! @brief Sets whether reads to the PMP region succeed */ |
| unsigned int R : 1; |
| /*! @brief Sets whether writes to the PMP region succeed */ |
| unsigned int W : 1; |
| /*! @brief Sets whether the PMP region is executable */ |
| unsigned int X : 1; |
| |
| /*! @brief Sets the addressing mode of the PMP region */ |
| enum metal_pmp_address_mode A : 2; |
| |
| int _pad : 2; |
| |
| /*! @brief Sets whether the PMP region is locked */ |
| enum metal_pmp_locked { |
| METAL_PMP_UNLOCKED = 0, |
| METAL_PMP_LOCKED = 1 |
| } L : 1; |
| }; |
| |
| /*! |
| * @brief A handle for the PMP device |
| */ |
| struct metal_pmp { |
| /* The minimum granularity of the PMP region. Set by metal_pmp_init */ |
| uintptr_t _granularity[METAL_MAX_CORES]; |
| }; |
| |
| /*! |
| * @brief Get the PMP device handle |
| */ |
| struct metal_pmp *metal_pmp_get_device(void); |
| |
| /*! |
| * @brief Get the number of pmp regions for the hartid |
| */ |
| int metal_pmp_num_regions(int hartid); |
| |
| /*! |
| * @brief Initialize the PMP |
| * @param pmp The PMP device handle to be initialized |
| * |
| * The PMP initialization routine is optional and may be called as many times |
| * as is desired. The effect of the initialization routine is to attempt to set |
| * all regions to unlocked and disabled, as well as to clear the X, W, and R |
| * bits. Only the pmp configuration of the hart which executes the routine will |
| * be affected. |
| * |
| * If any regions are fused to preset values by the implementation or locked, |
| * those PMP regions will silently remain uninitialized. |
| */ |
| void metal_pmp_init(struct metal_pmp *pmp); |
| |
| /*! |
| * @brief Configure a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to configure |
| * @param config The desired configuration of the PMP region |
| * @param address The desired address of the PMP region |
| * @return 0 upon success |
| */ |
| int metal_pmp_set_region(struct metal_pmp *pmp, unsigned int region, struct metal_pmp_config config, size_t address); |
| |
| /*! |
| * @brief Get the configuration for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @param config Variable to store the PMP region configuration |
| * @param address Variable to store the PMP region address |
| * @return 0 if the region is read successfully |
| */ |
| int metal_pmp_get_region(struct metal_pmp *pmp, unsigned int region, struct metal_pmp_config *config, size_t *address); |
| |
| /*! |
| * @brief Lock a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to lock |
| * @return 0 if the region is successfully locked |
| */ |
| int metal_pmp_lock(struct metal_pmp *pmp, unsigned int region); |
| |
| /*! |
| * @brief Set the address for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to set |
| * @param address The desired address of the PMP region |
| * @return 0 if the address is successfully set |
| */ |
| int metal_pmp_set_address(struct metal_pmp *pmp, unsigned int region, size_t address); |
| |
| /*! |
| * @brief Get the address of a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @return The address of the PMP region, or 0 if the region could not be read |
| */ |
| size_t metal_pmp_get_address(struct metal_pmp *pmp, unsigned int region); |
| |
| /*! |
| * @brief Set the addressing mode of a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to set |
| * @param mode The PMP addressing mode to set |
| * @return 0 if the addressing mode is successfully set |
| */ |
| int metal_pmp_set_address_mode(struct metal_pmp *pmp, unsigned int region, enum metal_pmp_address_mode mode); |
| |
| /*! |
| * @brief Get the addressing mode of a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @return The address mode of the PMP region |
| */ |
| enum metal_pmp_address_mode metal_pmp_get_address_mode(struct metal_pmp *pmp, unsigned int region); |
| |
| /*! |
| * @brief Set the executable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to set |
| * @param X The desired value of the executable bit |
| * @return 0 if the executable bit is successfully set |
| */ |
| int metal_pmp_set_executable(struct metal_pmp *pmp, unsigned int region, int X); |
| |
| /*! |
| * @brief Get the executable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @return the value of the executable bit |
| */ |
| int metal_pmp_get_executable(struct metal_pmp *pmp, unsigned int region); |
| |
| /*! |
| * @brief Set the writable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to set |
| * @param W The desired value of the writable bit |
| * @return 0 if the writable bit is successfully set |
| */ |
| int metal_pmp_set_writeable(struct metal_pmp *pmp, unsigned int region, int W); |
| |
| /*! |
| * @brief Get the writable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @return the value of the writable bit |
| */ |
| int metal_pmp_get_writeable(struct metal_pmp *pmp, unsigned int region); |
| |
| /*! |
| * @brief Set the readable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to set |
| * @param R The desired value of the readable bit |
| * @return 0 if the readable bit is successfully set |
| */ |
| int metal_pmp_set_readable(struct metal_pmp *pmp, unsigned int region, int R); |
| |
| /*! |
| * @brief Set the readable bit for a PMP region |
| * @param pmp The PMP device handle |
| * @param region The PMP region to read |
| * @return the value of the readable bit |
| */ |
| int metal_pmp_get_readable(struct metal_pmp *pmp, unsigned int region); |
| |
| #endif |
