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 */ 83