arm_mmu.h

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/*
 * ARMv7 MMU support
 *
 * Copyright (c) 2021 Weidmueller Interface GmbH & Co. KG
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_ARCH_AARCH32_ARM_MMU_H_
#define ZEPHYR_INCLUDE_ARCH_AARCH32_ARM_MMU_H_
 
#ifndef _ASMLANGUAGE
 
#include <stdint.h>
#include <stdlib.h>
 
/*
 * Comp.:
 * ARM Architecture Reference Manual, ARMv7-A and ARMv7-R edition,
 * ARM document ID DDI0406C Rev. d, March 2018
 * Memory type definitions:
 * Table B3-10, chap. B3.8.2, p. B3-1363f.
 * Outer / inner cache attributes for cacheable memory:
 * Table B3-11, chap. B3.8.2, p. B3-1364
 */
 
/*
 * The following definitions are used when specifying a memory
 * range to be mapped at boot time using the MMU_REGION_ENTRY
 * macro.
 */
#define MT_STRONGLY_ORDERED             BIT(0)
#define MT_DEVICE                       BIT(1)
#define MT_NORMAL                       BIT(2)
#define MT_MASK                         0x7
 
#define MPERM_R                         BIT(3)
#define MPERM_W                         BIT(4)
#define MPERM_X                         BIT(5)
#define MPERM_UNPRIVILEGED              BIT(6)
 
#define MATTR_NON_SECURE                BIT(7)
#define MATTR_NON_GLOBAL                BIT(8)
#define MATTR_SHARED                    BIT(9)
#define MATTR_CACHE_OUTER_WB_WA         BIT(10)
#define MATTR_CACHE_OUTER_WT_nWA        BIT(11)
#define MATTR_CACHE_OUTER_WB_nWA        BIT(12)
#define MATTR_CACHE_INNER_WB_WA         BIT(13)
#define MATTR_CACHE_INNER_WT_nWA        BIT(14)
#define MATTR_CACHE_INNER_WB_nWA        BIT(15)
 
#define MATTR_MAY_MAP_L1_SECTION        BIT(16)
 
/*
 * The following macros are used for adding constant entries
 * mmu_regions array of the mmu_config struct. Use MMU_REGION_ENTRY
 * for the specification of mappings whose PA and VA differ,
 * the use of MMU_REGION_FLAT_ENTRY always results in an identity
 * mapping, which are used for the mappings of the Zephyr image's
 * code and data.
 */
#define MMU_REGION_ENTRY(_name, _base_pa, _base_va, _size, _attrs) \
        {\
                .name    = _name, \
                .base_pa = _base_pa, \
                .base_va = _base_va, \
                .size    = _size, \
                .attrs   = _attrs, \
        }
#define MMU_REGION_ENTRY(_name, _base_pa, _base_va, _size, _attrs) \ …
 
#define MMU_REGION_FLAT_ENTRY(name, adr, sz, attrs) \
        MMU_REGION_ENTRY(name, adr, adr, sz, attrs)
#define MMU_REGION_FLAT_ENTRY(name, adr, sz, attrs) \ …
 
/*
 * @brief Auto generate mmu region entry for node_id
 *
 * Example usage:
 *
 * @code{.c}
 *      DT_FOREACH_STATUS_OKAY_VARGS(nxp_imx_gpio,
 *                                MMU_REGION_DT_FLAT_ENTRY,
 *                               (MT_DEVICE_nGnRnE | MT_P_RW_U_NA | MT_NS))
 * @endcode
 *
 * @note  Since devicetree_generated.h does not include
 *        node_id##_P_reg_FOREACH_PROP_ELEM* definitions,
 *        we can't automate dts node with multiple reg
 *        entries.
 */
#define MMU_REGION_DT_FLAT_ENTRY(node_id, attrs)  \
        MMU_REGION_FLAT_ENTRY(DT_NODE_FULL_NAME(node_id), \
                                  DT_REG_ADDR(node_id), \
                                  DT_REG_SIZE(node_id), \
                                  attrs),
#define MMU_REGION_DT_FLAT_ENTRY(node_id, attrs)  \ …
 
/*
 * @brief Auto generate mmu region entry for status = "okay"
 *        nodes compatible to a driver
 *
 * Example usage:
 *
 * @code{.c}
 *      MMU_REGION_DT_COMPAT_FOREACH_FLAT_ENTRY(nxp_imx_gpio,
 *                               (MT_DEVICE_nGnRnE | MT_P_RW_U_NA | MT_NS))
 * @endcode
 *
 * @note  This is a wrapper of @ref MMU_REGION_DT_FLAT_ENTRY
 */
#define MMU_REGION_DT_COMPAT_FOREACH_FLAT_ENTRY(compat, attr) \
        DT_FOREACH_STATUS_OKAY_VARGS(compat, \
        MMU_REGION_DT_FLAT_ENTRY, attr)
#define MMU_REGION_DT_COMPAT_FOREACH_FLAT_ENTRY(compat, attr) \ …
 
/* Region definition data structure */
struct arm_mmu_region {
        /* Region Base Physical Address */
        uintptr_t  base_pa;
        /* Region Base Virtual Address */
        uintptr_t  base_va;
        /* Region size */
        size_t     size;
        /* Region Name */
        const char *name;
        /* Region Attributes */
        uint32_t   attrs;
};
struct arm_mmu_region {…};
 
/* MMU configuration data structure */
struct arm_mmu_config {
        /* Number of regions */
        uint32_t                    num_regions;
        /* Regions */
        const struct arm_mmu_region *mmu_regions;
};
struct arm_mmu_config {…};
 
/*
 * Reference to the MMU configuration.
 *
 * This struct is defined and populated for each SoC (in the SoC definition),
 * and holds the build-time configuration information for the fixed MMU
 * regions enabled during kernel initialization.
 */
extern const struct arm_mmu_config mmu_config;
 
int z_arm_mmu_init(void);
 
#endif /* _ASMLANGUAGE */
 
#endif /* ZEPHYR_INCLUDE_ARCH_AARCH32_ARM_MMU_H_ */