| /* |
| * Copyright (c) 2017 Linaro Limited. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| #include <zephyr/device.h> |
| #include <zephyr/init.h> |
| #include <zephyr/kernel.h> |
| #include <zephyr/kernel_structs.h> |
| |
| #include "arm_core_mpu_dev.h" |
| #include <zephyr/linker/linker-defs.h> |
| |
| #define LOG_LEVEL CONFIG_MPU_LOG_LEVEL |
| #include <zephyr/logging/log.h> |
| LOG_MODULE_REGISTER(mpu); |
| |
| /* |
| * Maximum number of dynamic memory partitions that may be supplied to the MPU |
| * driver for programming during run-time. Note that the actual number of the |
| * available MPU regions for dynamic programming depends on the number of the |
| * static MPU regions currently being programmed, and the total number of HW- |
| * available MPU regions. This macro is only used internally in function |
| * z_arm_configure_dynamic_mpu_regions(), to reserve sufficient area for the |
| * array of dynamic regions passed to the underlying driver. |
| */ |
| #if defined(CONFIG_USERSPACE) |
| #define _MAX_DYNAMIC_MPU_REGIONS_NUM \ |
| CONFIG_MAX_DOMAIN_PARTITIONS + /* User thread stack */ 1 + \ |
| (IS_ENABLED(CONFIG_MPU_STACK_GUARD) ? 1 : 0) |
| #else |
| #define _MAX_DYNAMIC_MPU_REGIONS_NUM \ |
| (IS_ENABLED(CONFIG_MPU_STACK_GUARD) ? 1 : 0) |
| #endif /* CONFIG_USERSPACE */ |
| |
| /* Convenience macros to denote the start address and the size of the system |
| * memory area, where dynamic memory regions may be programmed at run-time. |
| */ |
| #if defined(CONFIG_USERSPACE) |
| #define _MPU_DYNAMIC_REGIONS_AREA_START ((uint32_t)&_app_smem_start) |
| #else |
| #define _MPU_DYNAMIC_REGIONS_AREA_START ((uint32_t)&__kernel_ram_start) |
| #endif /* CONFIG_USERSPACE */ |
| #define _MPU_DYNAMIC_REGIONS_AREA_SIZE ((uint32_t)&__kernel_ram_end - \ |
| _MPU_DYNAMIC_REGIONS_AREA_START) |
| |
| #if !defined(CONFIG_MULTITHREADING) && defined(CONFIG_MPU_STACK_GUARD) |
| K_THREAD_STACK_DECLARE(z_main_stack, CONFIG_MAIN_STACK_SIZE); |
| #endif |
| |
| #if defined(CONFIG_FPU) && defined(CONFIG_FPU_SHARING) \ |
| && defined(CONFIG_MPU_STACK_GUARD) |
| uint32_t z_arm_mpu_stack_guard_and_fpu_adjust(struct k_thread *thread); |
| #endif |
| |
| #if defined(CONFIG_CODE_DATA_RELOCATION_SRAM) |
| extern char __sram_text_start[]; |
| extern char __sram_text_size[]; |
| #endif |
| |
| static const struct z_arm_mpu_partition static_regions[] = { |
| #if defined(CONFIG_COVERAGE_GCOV) && defined(CONFIG_USERSPACE) |
| { |
| /* GCOV code coverage accounting area. Needs User permissions |
| * to function |
| */ |
| .start = (uint32_t)&__gcov_bss_start, |
| .size = (uint32_t)&__gcov_bss_size, |
| .attr = K_MEM_PARTITION_P_RW_U_RW, |
| }, |
| #endif /* CONFIG_COVERAGE_GCOV && CONFIG_USERSPACE */ |
| #if defined(CONFIG_NOCACHE_MEMORY) |
| { |
| /* Special non-cacheable RAM area */ |
| .start = (uint32_t)&_nocache_ram_start, |
| .size = (uint32_t)&_nocache_ram_size, |
| .attr = K_MEM_PARTITION_P_RW_U_NA_NOCACHE, |
| }, |
| #endif /* CONFIG_NOCACHE_MEMORY */ |
| #if defined(CONFIG_ARCH_HAS_RAMFUNC_SUPPORT) |
| { |
| /* Special RAM area for program text */ |
| .start = (uint32_t)&__ramfunc_start, |
| .size = (uint32_t)&__ramfunc_size, |
| .attr = K_MEM_PARTITION_P_RX_U_RX, |
| }, |
| #endif /* CONFIG_ARCH_HAS_RAMFUNC_SUPPORT */ |
| #if defined(CONFIG_CODE_DATA_RELOCATION_SRAM) |
| { |
| /* RAM area for relocated text */ |
| .start = (uint32_t)&__sram_text_start, |
| .size = (uint32_t)&__sram_text_size, |
| .attr = K_MEM_PARTITION_P_RX_U_RX, |
| }, |
| #endif /* CONFIG_CODE_DATA_RELOCATION_SRAM */ |
| #if !defined(CONFIG_MULTITHREADING) && defined(CONFIG_MPU_STACK_GUARD) |
| /* Main stack MPU guard to detect overflow. |
| * Note: |
| * FPU_SHARING and USERSPACE are not supported features |
| * under CONFIG_MULTITHREADING=n, so the MPU guard (if |
| * exists) is reserved aside of CONFIG_MAIN_STACK_SIZE |
| * and there is no requirement for larger guard area (FP |
| * context is not stacked). |
| */ |
| { |
| .start = (uint32_t)z_main_stack, |
| .size = (uint32_t)MPU_GUARD_ALIGN_AND_SIZE, |
| .attr = K_MEM_PARTITION_P_RO_U_NA, |
| }, |
| #endif /* !CONFIG_MULTITHREADING && CONFIG_MPU_STACK_GUARD */ |
| }; |
| |
| /** |
| * @brief Use the HW-specific MPU driver to program |
| * the static MPU regions. |
| * |
| * Program the static MPU regions using the HW-specific MPU driver. The |
| * function is meant to be invoked only once upon system initialization. |
| * |
| * If the function attempts to configure a number of regions beyond the |
| * MPU HW limitations, the system behavior will be undefined. |
| * |
| * For some MPU architectures, such as the unmodified ARMv8-M MPU, |
| * the function must execute with MPU enabled. |
| */ |
| void z_arm_configure_static_mpu_regions(void) |
| { |
| /* Configure the static MPU regions within firmware SRAM boundaries. |
| * Start address of the image is given by _image_ram_start. The end |
| * of the firmware SRAM area is marked by __kernel_ram_end, taking |
| * into account the unused SRAM area, as well. |
| */ |
| arm_core_mpu_configure_static_mpu_regions(static_regions, |
| ARRAY_SIZE(static_regions), |
| (uint32_t)&_image_ram_start, |
| (uint32_t)&__kernel_ram_end); |
| |
| #if defined(CONFIG_MPU_REQUIRES_NON_OVERLAPPING_REGIONS) && \ |
| defined(CONFIG_MULTITHREADING) |
| /* Define a constant array of z_arm_mpu_partition objects that holds the |
| * boundaries of the areas, inside which dynamic region programming |
| * is allowed. The information is passed to the underlying driver at |
| * initialization. |
| */ |
| const struct z_arm_mpu_partition dyn_region_areas[] = { |
| { |
| .start = _MPU_DYNAMIC_REGIONS_AREA_START, |
| .size = _MPU_DYNAMIC_REGIONS_AREA_SIZE, |
| } |
| }; |
| |
| arm_core_mpu_mark_areas_for_dynamic_regions(dyn_region_areas, |
| ARRAY_SIZE(dyn_region_areas)); |
| #endif /* CONFIG_MPU_REQUIRES_NON_OVERLAPPING_REGIONS */ |
| } |
| |
| extern void arm_core_mpu_enable(void); |
| extern void arm_core_mpu_disable(void); |
| /** |
| * @brief Use the HW-specific MPU driver to program |
| * the dynamic MPU regions. |
| * |
| * Program the dynamic MPU regions using the HW-specific MPU |
| * driver. This function is meant to be invoked every time the |
| * memory map is to be re-programmed, e.g during thread context |
| * switch, entering user mode, reconfiguring memory domain, etc. |
| * |
| * For some MPU architectures, such as the unmodified ARMv8-M MPU, |
| * the function must execute with MPU enabled. |
| * |
| * This function is not inherently thread-safe, but the memory domain |
| * spinlock needs to be held anyway. |
| */ |
| void z_arm_configure_dynamic_mpu_regions(struct k_thread *thread) |
| { |
| /* Define an array of z_arm_mpu_partition objects to hold the configuration |
| * of the respective dynamic MPU regions to be programmed for |
| * the given thread. The array of partitions (along with its |
| * actual size) will be supplied to the underlying MPU driver. |
| * |
| * The drivers of what regions get configured are CONFIG_USERSPACE, |
| * CONFIG_MPU_STACK_GUARD, and K_USER/supervisor threads. |
| * |
| * If CONFIG_USERSPACE is defined and the thread is a member of any |
| * memory domain then any partitions defined within that domain get a |
| * defined region. |
| * |
| * If CONFIG_USERSPACE is defined and the thread is a user thread |
| * (K_USER) the usermode thread stack is defined a region. |
| * |
| * IF CONFIG_MPU_STACK_GUARD is defined the thread is a supervisor |
| * thread, the stack guard will be defined in front of the |
| * thread->stack_info.start. On a K_USER thread, the guard is defined |
| * in front of the privilege mode stack, thread->arch.priv_stack_start. |
| */ |
| static struct z_arm_mpu_partition |
| dynamic_regions[_MAX_DYNAMIC_MPU_REGIONS_NUM]; |
| |
| uint8_t region_num = 0U; |
| |
| #if defined(CONFIG_USERSPACE) |
| /* Memory domain */ |
| LOG_DBG("configure thread %p's domain", thread); |
| struct k_mem_domain *mem_domain = thread->mem_domain_info.mem_domain; |
| |
| if (mem_domain) { |
| LOG_DBG("configure domain: %p", mem_domain); |
| uint32_t num_partitions = mem_domain->num_partitions; |
| struct k_mem_partition *partition; |
| int i; |
| |
| LOG_DBG("configure domain: %p", mem_domain); |
| |
| for (i = 0; i < CONFIG_MAX_DOMAIN_PARTITIONS; i++) { |
| partition = &mem_domain->partitions[i]; |
| if (partition->size == 0) { |
| /* Zero size indicates a non-existing |
| * memory partition. |
| */ |
| continue; |
| } |
| LOG_DBG("set region 0x%lx 0x%x", |
| partition->start, partition->size); |
| __ASSERT(region_num < _MAX_DYNAMIC_MPU_REGIONS_NUM, |
| "Out-of-bounds error for dynamic region map."); |
| |
| dynamic_regions[region_num].start = partition->start; |
| dynamic_regions[region_num].size = partition->size; |
| dynamic_regions[region_num].attr = partition->attr; |
| |
| region_num++; |
| num_partitions--; |
| if (num_partitions == 0U) { |
| break; |
| } |
| } |
| } |
| /* Thread user stack */ |
| LOG_DBG("configure user thread %p's context", thread); |
| if (thread->arch.priv_stack_start) { |
| /* K_USER thread stack needs a region */ |
| uintptr_t base = (uintptr_t)thread->stack_obj; |
| size_t size = thread->stack_info.size + |
| (thread->stack_info.start - base); |
| |
| __ASSERT(region_num < _MAX_DYNAMIC_MPU_REGIONS_NUM, |
| "Out-of-bounds error for dynamic region map."); |
| |
| dynamic_regions[region_num].start = base; |
| dynamic_regions[region_num].size = size; |
| dynamic_regions[region_num].attr = K_MEM_PARTITION_P_RW_U_RW; |
| |
| region_num++; |
| } |
| #endif /* CONFIG_USERSPACE */ |
| |
| #if defined(CONFIG_MPU_STACK_GUARD) |
| /* Define a stack guard region for either the thread stack or the |
| * supervisor/privilege mode stack depending on the type of thread |
| * being mapped. |
| */ |
| |
| /* Privileged stack guard */ |
| uintptr_t guard_start; |
| size_t guard_size = MPU_GUARD_ALIGN_AND_SIZE; |
| |
| #if defined(CONFIG_FPU) && defined(CONFIG_FPU_SHARING) |
| guard_size = z_arm_mpu_stack_guard_and_fpu_adjust(thread); |
| #endif |
| |
| #if defined(CONFIG_USERSPACE) |
| if (thread->arch.priv_stack_start) { |
| /* A K_USER thread has the stack guard protecting the privilege |
| * stack and not on the usermode stack because the user mode |
| * stack already has its own defined memory region. |
| */ |
| guard_start = thread->arch.priv_stack_start - guard_size; |
| |
| __ASSERT((uintptr_t)&z_priv_stacks_ram_start <= guard_start, |
| "Guard start: (0x%lx) below privilege stacks boundary: (%p)", |
| guard_start, z_priv_stacks_ram_start); |
| } else |
| #endif /* CONFIG_USERSPACE */ |
| { |
| /* A supervisor thread only has the normal thread stack to |
| * protect with a stack guard. |
| */ |
| guard_start = thread->stack_info.start - guard_size; |
| #ifdef CONFIG_USERSPACE |
| __ASSERT((uintptr_t)thread->stack_obj == guard_start, |
| "Guard start (0x%lx) not beginning at stack object (%p)\n", |
| guard_start, thread->stack_obj); |
| #endif /* CONFIG_USERSPACE */ |
| } |
| |
| __ASSERT(region_num < _MAX_DYNAMIC_MPU_REGIONS_NUM, |
| "Out-of-bounds error for dynamic region map."); |
| |
| dynamic_regions[region_num].start = guard_start; |
| dynamic_regions[region_num].size = guard_size; |
| dynamic_regions[region_num].attr = K_MEM_PARTITION_P_RO_U_NA; |
| |
| region_num++; |
| #endif /* CONFIG_MPU_STACK_GUARD */ |
| |
| /* Configure the dynamic MPU regions */ |
| #ifdef CONFIG_AARCH32_ARMV8_R |
| arm_core_mpu_disable(); |
| #endif |
| arm_core_mpu_configure_dynamic_mpu_regions(dynamic_regions, |
| region_num); |
| #ifdef CONFIG_AARCH32_ARMV8_R |
| arm_core_mpu_enable(); |
| #endif |
| } |
| |
| #if defined(CONFIG_USERSPACE) |
| int arch_mem_domain_max_partitions_get(void) |
| { |
| int available_regions = arm_core_mpu_get_max_available_dyn_regions(); |
| |
| available_regions -= |
| ARM_CORE_MPU_NUM_MPU_REGIONS_FOR_THREAD_STACK; |
| |
| if (IS_ENABLED(CONFIG_MPU_STACK_GUARD)) { |
| available_regions -= |
| ARM_CORE_MPU_NUM_MPU_REGIONS_FOR_MPU_STACK_GUARD; |
| } |
| |
| return ARM_CORE_MPU_MAX_DOMAIN_PARTITIONS_GET(available_regions); |
| } |
| |
| int arch_buffer_validate(void *addr, size_t size, int write) |
| { |
| return arm_core_mpu_buffer_validate(addr, size, write); |
| } |
| |
| #endif /* CONFIG_USERSPACE */ |