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/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _ASM_X86_E820_H
#define _ASM_X86_E820_H
#define E820MAP 0x2d0 /* our map */
#define E820MAX 128   /* number of entries in E820MAP */

/*
 * Legacy E820 BIOS limits us to 128 (E820MAX) nodes due to the
 * constrained space in the zeropage.  If we have more nodes than
 * that, and if we've booted off EFI firmware, then the EFI tables
 * passed us from the EFI firmware can list more nodes.  Size our
 * internal memory map tables to have room for these additional
 * nodes, based on up to three entries per node for which the
 * kernel was built: MAX_NUMNODES == (1 << CONFIG_NODES_SHIFT),
 * plus E820MAX, allowing space for the possible duplicate E820
 * entries that might need room in the same arrays, prior to the
 * call to sanitize_e820_map() to remove duplicates.  The allowance
 * of three memory map entries per node is "enough" entries for
 * the initial hardware platform motivating this mechanism to make
 * use of additional EFI map entries.  Future platforms may want
 * to allow more than three entries per node or otherwise refine
 * this size.
 */

#define E820_X_MAX E820MAX

#define E820NR 0x1e8 /* # entries in E820MAP */

#define E820_RAM      1
#define E820_RESERVED 2
#define E820_ACPI     3
#define E820_NVS      4
#define E820_UNUSABLE 5
#define E820_PMEM     7

/*
 * This is a non-standardized way to represent ADR or NVDIMM regions that
 * persist over a reboot.  The kernel will ignore their special capabilities
 * unless the CONFIG_X86_PMEM_LEGACY option is set.
 *
 * ( Note that older platforms also used 6 for the same type of memory,
 *   but newer versions switched to 12 as 6 was assigned differently.  Some
 *   time they will learn... )
 */
#define E820_PRAM 12

/*
 * reserved RAM used by kernel itself
 * if CONFIG_INTEL_TXT is enabled, memory of this type will be
 * included in the S3 integrity calculation and so should not include
 * any memory that BIOS might alter over the S3 transition
 */
#define E820_RESERVED_KERN 128

#ifndef __ASSEMBLER__
#include <linux/types.h>
struct e820entry {
	__u64 addr; /* start of memory segment */
	__u64 size; /* size of memory segment */
	__u32 type; /* type of memory segment */
} __attribute__((packed));

struct e820map {
	__u32 nr_map;
	struct e820entry map[E820_X_MAX];
};

#define ISA_START_ADDRESS 0xa0000
#define ISA_END_ADDRESS	  0x100000

#define BIOS_BEGIN 0x000a0000
#define BIOS_END   0x00100000

#define BIOS_ROM_BASE 0xffe00000
#define BIOS_ROM_END  0xffffffff

#endif /* __ASSEMBLER__ */

#endif /* _ASM_X86_E820_H */