mm.h

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/*
 * Copyright (c) 2020 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_KERNEL_INTERNAL_MM_H
#define ZEPHYR_INCLUDE_KERNEL_INTERNAL_MM_H
 
#include <zephyr/sys/util.h>
#include <zephyr/toolchain.h>
 
/*
 * This is the offset to subtract from a virtual address mapped in the
 * kernel's permanent mapping of RAM, to obtain its physical address.
 *
 *     virt_addr = phys_addr + Z_MEM_VM_OFFSET
 *
 * This only works for virtual addresses within the interval
 * [CONFIG_KERNEL_VM_BASE, CONFIG_KERNEL_VM_BASE + (CONFIG_SRAM_SIZE * 1024)).
 *
 * These macros are intended for assembly, linker code, and static initializers.
 * Use with care.
 *
 * Note that when demand paging is active, these will only work with page
 * frames that are pinned to their virtual mapping at boot.
 *
 * TODO: This will likely need to move to an arch API or need additional
 * constraints defined.
 */
#ifdef CONFIG_MMU
#define Z_MEM_VM_OFFSET ((CONFIG_KERNEL_VM_BASE + CONFIG_KERNEL_VM_OFFSET) - \
                         (CONFIG_SRAM_BASE_ADDRESS + CONFIG_SRAM_OFFSET))
#else
#define Z_MEM_VM_OFFSET 0
#endif /* CONFIG_MMU */
 
#define Z_MEM_PHYS_ADDR(virt)   ((virt) - Z_MEM_VM_OFFSET)
#define Z_MEM_VIRT_ADDR(phys)   ((phys) + Z_MEM_VM_OFFSET)
 
#if Z_MEM_VM_OFFSET != 0
#define Z_VM_KERNEL 1
#ifdef CONFIG_XIP
#error "XIP and a virtual memory kernel are not allowed"
#endif
#endif
 
#ifndef _ASMLANGUAGE
#include <stdint.h>
#include <stddef.h>
#include <inttypes.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/sys/mem_manage.h>
 
/* Just like Z_MEM_PHYS_ADDR() but with type safety and assertions */
static inline uintptr_t z_mem_phys_addr(void *virt)
{
        uintptr_t addr = (uintptr_t)virt;
 
#if defined(CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK)
        __ASSERT(sys_mm_is_virt_addr_in_range(virt),
                 "address %p not in permanent mappings", virt);
#elif defined(CONFIG_MMU)
        __ASSERT(
#if CONFIG_KERNEL_VM_BASE != 0
                 (addr >= CONFIG_KERNEL_VM_BASE) &&
#endif /* CONFIG_KERNEL_VM_BASE != 0 */
#if (CONFIG_KERNEL_VM_BASE + CONFIG_KERNEL_VM_SIZE) != 0
                 (addr < (CONFIG_KERNEL_VM_BASE +
                          (CONFIG_KERNEL_VM_SIZE))),
#else
                 false,
#endif /* CONFIG_KERNEL_VM_BASE + CONFIG_KERNEL_VM_SIZE != 0 */
                 "address %p not in permanent mappings", virt);
#else
        /* Should be identity-mapped */
        __ASSERT(
#if CONFIG_SRAM_BASE_ADDRESS != 0
                 (addr >= CONFIG_SRAM_BASE_ADDRESS) &&
#endif /* CONFIG_SRAM_BASE_ADDRESS != 0 */
#if (CONFIG_SRAM_BASE_ADDRESS + (CONFIG_SRAM_SIZE * 1024UL)) != 0
                 (addr < (CONFIG_SRAM_BASE_ADDRESS +
                          (CONFIG_SRAM_SIZE * 1024UL))),
#else
                 false,
#endif /* (CONFIG_SRAM_BASE_ADDRESS + (CONFIG_SRAM_SIZE * 1024UL)) != 0 */
                 "physical address 0x%lx not in RAM",
                 (unsigned long)addr);
#endif /* CONFIG_MMU */
 
        /* TODO add assertion that this page is pinned to boot mapping,
         * the above checks won't be sufficient with demand paging
         */
 
        return Z_MEM_PHYS_ADDR(addr);
}
 
/* Just like Z_MEM_VIRT_ADDR() but with type safety and assertions */
static inline void *z_mem_virt_addr(uintptr_t phys)
{
#if defined(CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK)
        __ASSERT(sys_mm_is_phys_addr_in_range(phys),
                "physical address 0x%lx not in RAM", (unsigned long)phys);
#else
        __ASSERT(
#if CONFIG_SRAM_BASE_ADDRESS != 0
                 (phys >= CONFIG_SRAM_BASE_ADDRESS) &&
#endif /* CONFIG_SRAM_BASE_ADDRESS != 0 */
#if (CONFIG_SRAM_BASE_ADDRESS + (CONFIG_SRAM_SIZE * 1024UL)) != 0
                 (phys < (CONFIG_SRAM_BASE_ADDRESS +
                          (CONFIG_SRAM_SIZE * 1024UL))),
#else
                 false,
#endif /* (CONFIG_SRAM_BASE_ADDRESS + (CONFIG_SRAM_SIZE * 1024UL)) != 0 */
                 "physical address 0x%lx not in RAM", (unsigned long)phys);
#endif /* CONFIG_KERNEL_VM_USE_CUSTOM_MEM_RANGE_CHECK */
 
        /* TODO add assertion that this page frame is pinned to boot mapping,
         * the above check won't be sufficient with demand paging
         */
 
        return (void *)Z_MEM_VIRT_ADDR(phys);
}
 
#ifdef __cplusplus
extern "C" {
#endif
 
void z_phys_map(uint8_t **virt_ptr, uintptr_t phys, size_t size,
                uint32_t flags);
 
void z_phys_unmap(uint8_t *virt, size_t size);
 
void *k_mem_map_impl(uintptr_t phys, size_t size, uint32_t flags, bool is_anon);
 
void k_mem_unmap_impl(void *addr, size_t size, bool is_anon);
 
#ifdef __cplusplus
}
#endif
 
#endif /* !_ASMLANGUAGE */
#endif /* ZEPHYR_INCLUDE_KERNEL_INTERNAL_MM_H */