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-rw-r--r--arch/x86/include/uapi/asm/e820.h82
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
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+++ b/arch/x86/include/uapi/asm/e820.h
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+/* 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 */