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-rw-r--r--arch/x86/include/asm/e820/types.h104
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diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h
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+#ifndef _ASM_E820_TYPES_H
+#define _ASM_E820_TYPES_H
+
+#include <uapi/asm/bootparam.h>
+
+/*
+ * These are the E820 types known to the kernel:
+ */
+enum e820_type {
+ E820_TYPE_RAM = 1,
+ E820_TYPE_RESERVED = 2,
+ E820_TYPE_ACPI = 3,
+ E820_TYPE_NVS = 4,
+ E820_TYPE_UNUSABLE = 5,
+ E820_TYPE_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=y 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... )
+ */
+ E820_TYPE_PRAM = 12,
+
+ /*
+ * Reserved RAM used by the kernel itself if
+ * CONFIG_INTEL_TXT=y is enabled, memory of this type
+ * will be included in the S3 integrity calculation
+ * and so should not include any memory that the BIOS
+ * might alter over the S3 transition:
+ */
+ E820_TYPE_RESERVED_KERN = 128,
+};
+
+/*
+ * A single E820 map entry, describing a memory range of [addr...addr+size-1],
+ * of 'type' memory type:
+ *
+ * (We pack it because there can be thousands of them on large systems.)
+ */
+struct e820_entry {
+ u64 addr;
+ u64 size;
+ enum e820_type type;
+} __attribute__((packed));
+
+/*
+ * The legacy E820 BIOS limits us to 128 (E820_MAX_ENTRIES_ZEROPAGE) nodes
+ * due to the constrained space in the zeropage.
+ *
+ * On large systems we can easily have thousands of nodes with RAM,
+ * which cannot be fit into so few entries - so we have a mechanism
+ * to extend the e820 table size at build-time, via the E820_MAX_ENTRIES
+ * define below.
+ *
+ * ( Those extra entries are enumerated via the EFI memory map, not
+ * via the legacy zeropage mechanism. )
+ *
+ * Size our internal memory map tables to have room for these additional
+ * entries, based on a heuristic calculation: up to three entries per
+ * NUMA node, plus E820_MAX_ENTRIES_ZEROPAGE for some extra space.
+ *
+ * This allows for bootstrap/firmware quirks such as possible duplicate
+ * E820 entries that might need room in the same arrays, prior to the
+ * call to e820__update_table() 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.
+ */
+
+#include <linux/numa.h>
+
+#define E820_MAX_ENTRIES (E820_MAX_ENTRIES_ZEROPAGE + 3*MAX_NUMNODES)
+
+/*
+ * The whole array of E820 entries:
+ */
+struct e820_table {
+ __u32 nr_entries;
+ struct e820_entry entries[E820_MAX_ENTRIES];
+};
+
+/*
+ * Various well-known legacy memory ranges in physical memory:
+ */
+#define ISA_START_ADDRESS 0x000a0000
+#define ISA_END_ADDRESS 0x00100000
+
+#define BIOS_BEGIN 0x000a0000
+#define BIOS_END 0x00100000
+
+#define HIGH_MEMORY 0x00100000
+
+#define BIOS_ROM_BASE 0xffe00000
+#define BIOS_ROM_END 0xffffffff
+
+#endif /* _ASM_E820_TYPES_H */