arch/x86/include/uapi/asm/e820.h

   1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2 #ifndef _UAPI_ASM_X86_E820_H
   3 #define _UAPI_ASM_X86_E820_H
   4 #define E820MAP 0x2d0           /* our map */
   5 #define E820MAX 128             /* number of entries in E820MAP */
   6
   7 /*
   8  * Legacy E820 BIOS limits us to 128 (E820MAX) nodes due to the
   9  * constrained space in the zeropage.  If we have more nodes than
  10  * that, and if we've booted off EFI firmware, then the EFI tables
  11  * passed us from the EFI firmware can list more nodes.  Size our
  12  * internal memory map tables to have room for these additional
  13  * nodes, based on up to three entries per node for which the
  14  * kernel was built: MAX_NUMNODES == (1 << CONFIG_NODES_SHIFT),
  15  * plus E820MAX, allowing space for the possible duplicate E820
  16  * entries that might need room in the same arrays, prior to the
  17  * call to sanitize_e820_map() to remove duplicates.  The allowance
  18  * of three memory map entries per node is "enough" entries for
  19  * the initial hardware platform motivating this mechanism to make
  20  * use of additional EFI map entries.  Future platforms may want
  21  * to allow more than three entries per node or otherwise refine
  22  * this size.
  23  */
  24
  25 #ifndef __KERNEL__
  26 #define E820_X_MAX E820MAX
  27 #endif
  28
  29 #define E820NR  0x1e8           /* # entries in E820MAP */
  30
  31 #define E820_RAM        1
  32 #define E820_RESERVED   2
  33 #define E820_ACPI       3
  34 #define E820_NVS        4
  35 #define E820_UNUSABLE   5
  36 #define E820_PMEM       7
  37
  38 /*
  39  * This is a non-standardized way to represent ADR or NVDIMM regions that
  40  * persist over a reboot.  The kernel will ignore their special capabilities
  41  * unless the CONFIG_X86_PMEM_LEGACY option is set.
  42  *
  43  * ( Note that older platforms also used 6 for the same type of memory,
  44  *   but newer versions switched to 12 as 6 was assigned differently.  Some
  45  *   time they will learn... )
  46  */
  47 #define E820_PRAM       12
  48
  49 /*
  50  * reserved RAM used by kernel itself
  51  * if CONFIG_INTEL_TXT is enabled, memory of this type will be
  52  * included in the S3 integrity calculation and so should not include
  53  * any memory that BIOS might alter over the S3 transition
  54  */
  55 #define E820_RESERVED_KERN        128
  56
  57 #ifndef __ASSEMBLY__
  58 #include <linux/types.h>
  59 struct e820entry {
  60         __u64 addr;     /* start of memory segment */
  61         __u64 size;     /* size of memory segment */
  62         __u32 type;     /* type of memory segment */
  63 } __attribute__((packed));
  64
  65 struct e820map {
  66         __u32 nr_map;
  67         struct e820entry map[E820_X_MAX];
  68 };
  69
  70 #define ISA_START_ADDRESS       0xa0000
  71 #define ISA_END_ADDRESS         0x100000
  72
  73 #define BIOS_BEGIN              0x000a0000
  74 #define BIOS_END                0x00100000
  75
  76 #define BIOS_ROM_BASE           0xffe00000
  77 #define BIOS_ROM_END            0xffffffff
  78
  79 #endif /* __ASSEMBLY__ */
  80
  81
  82 #endif /* _UAPI_ASM_X86_E820_H */