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Diffstat (limited to 'arch/x86/include/uapi/asm/e820.h')
-rw-r--r-- | arch/x86/include/uapi/asm/e820.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/x86/include/uapi/asm/e820.h b/arch/x86/include/uapi/asm/e820.h new file mode 100644 index 000000000..2f491efe3 --- /dev/null +++ b/arch/x86/include/uapi/asm/e820.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_X86_E820_H +#define _UAPI_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. + */ + +#ifndef __KERNEL__ +#define E820_X_MAX E820MAX +#endif + +#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 /* _UAPI_ASM_X86_E820_H */ |