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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 __ASSEMBLY__
#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 /* __ASSEMBLY__ */
#endif /* _ASM_X86_E820_H */
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