memmap.h

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/*
 * Copyright (c) 2019 Intel Corporation
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef ZEPHYR_INCLUDE_ARCH_X86_MEMMAP_H_
#define ZEPHYR_INCLUDE_ARCH_X86_MEMMAP_H_
 
#ifndef _ASMLANGUAGE
 
/*
 * The "source" of the memory map refers to where we got the data to fill in
 * the map. Order is important: if multiple sources are available, then the
 * numerically HIGHEST source wins, a manually-provided map being the "best".
 */
 
enum x86_memmap_source {
        X86_MEMMAP_SOURCE_DEFAULT,
        X86_MEMMAP_SOURCE_MULTIBOOT_MEM,
        X86_MEMMAP_SOURCE_MULTIBOOT_MMAP,
        X86_MEMMAP_SOURCE_MANUAL
};
 
extern enum x86_memmap_source x86_memmap_source;
 
/*
 * For simplicity, we maintain a fixed-sized array of memory regions.
 *
 * We don't only track available RAM -- we track unavailable regions, too:
 * sometimes we'll be given a map with overlapping regions. We have to be
 * pessimistic about what is considered "available RAM" and it's easier to
 * keep all the regions around than it is to correct incorrect maps. It's
 * also handy to have the entire map intact for diagnostic purposes.
 */
 
enum x86_memmap_entry_type {
        /*
         * the UNUSED entry must have a numerical 0 value, so
         * that partially-initialized arrays behave as expected.
         */
 
        X86_MEMMAP_ENTRY_UNUSED,        /* this entry is unused/invalid */
        X86_MEMMAP_ENTRY_RAM,           /* available RAM */
        X86_MEMMAP_ENTRY_ACPI,          /* reserved for ACPI */
        X86_MEMMAP_ENTRY_NVS,           /* preserve during hibernation */
        X86_MEMMAP_ENTRY_DEFECTIVE,     /* bad memory modules */
        X86_MEMMAP_ENTRY_UNKNOWN        /* unknown type, do not use */
};
 
struct x86_memmap_entry {
        uint64_t base;
        uint64_t length;
        enum x86_memmap_entry_type type;
};
 
extern struct x86_memmap_entry x86_memmap[];
 
/*
 * We keep track of kernel memory areas (text, data, etc.) in a table for
 * ease of reference. There's really no reason to export this table, or to
 * label the members, except for diagnostic purposes.
 */
 
struct x86_memmap_exclusion {
        char *name;
        void *start;            /* address of first byte of exclusion */
        void *end;              /* one byte past end of exclusion */
};
 
extern struct x86_memmap_exclusion x86_memmap_exclusions[];
extern int x86_nr_memmap_exclusions;
 
#endif /* _ASMLANGUAGE */
 
#endif /* ZEPHYR_INCLUDE_ARCH_X86_MEMMAP_H_ */