1/* SPDX-License-Identifier: MIT */
2/*
3 * Copyright (c) 2016, Citrix Systems, Inc.
4 */
5
6#ifndef __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__
7#define __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__
8
9/*
10 * Start of day structure passed to PVH guests and to HVM guests in %ebx.
11 *
12 * NOTE: nothing will be loaded at physical address 0, so a 0 value in any
13 * of the address fields should be treated as not present.
14 *
15 * 0 +----------------+
16 * | magic | Contains the magic value XEN_HVM_START_MAGIC_VALUE
17 * | | ("xEn3" with the 0x80 bit of the "E" set).
18 * 4 +----------------+
19 * | version | Version of this structure. Current version is 1. New
20 * | | versions are guaranteed to be backwards-compatible.
21 * 8 +----------------+
22 * | flags | SIF_xxx flags.
23 * 12 +----------------+
24 * | nr_modules | Number of modules passed to the kernel.
25 * 16 +----------------+
26 * | modlist_paddr | Physical address of an array of modules
27 * | | (layout of the structure below).
28 * 24 +----------------+
29 * | cmdline_paddr | Physical address of the command line,
30 * | | a zero-terminated ASCII string.
31 * 32 +----------------+
32 * | rsdp_paddr | Physical address of the RSDP ACPI data structure.
33 * 40 +----------------+
34 * | memmap_paddr | Physical address of the (optional) memory map. Only
35 * | | present in version 1 and newer of the structure.
36 * 48 +----------------+
37 * | memmap_entries | Number of entries in the memory map table. Zero
38 * | | if there is no memory map being provided. Only
39 * | | present in version 1 and newer of the structure.
40 * 52 +----------------+
41 * | reserved | Version 1 and newer only.
42 * 56 +----------------+
43 *
44 * The layout of each entry in the module structure is the following:
45 *
46 * 0 +----------------+
47 * | paddr | Physical address of the module.
48 * 8 +----------------+
49 * | size | Size of the module in bytes.
50 * 16 +----------------+
51 * | cmdline_paddr | Physical address of the command line,
52 * | | a zero-terminated ASCII string.
53 * 24 +----------------+
54 * | reserved |
55 * 32 +----------------+
56 *
57 * The layout of each entry in the memory map table is as follows:
58 *
59 * 0 +----------------+
60 * | addr | Base address
61 * 8 +----------------+
62 * | size | Size of mapping in bytes
63 * 16 +----------------+
64 * | type | Type of mapping as defined between the hypervisor
65 * | | and guest. See XEN_HVM_MEMMAP_TYPE_* values below.
66 * 20 +----------------|
67 * | reserved |
68 * 24 +----------------+
69 *
70 * The address and sizes are always a 64bit little endian unsigned integer.
71 *
72 * NB: Xen on x86 will always try to place all the data below the 4GiB
73 * boundary.
74 *
75 * Version numbers of the hvm_start_info structure have evolved like this:
76 *
77 * Version 0: Initial implementation.
78 *
79 * Version 1: Added the memmap_paddr/memmap_entries fields (plus 4 bytes of
80 * padding) to the end of the hvm_start_info struct. These new
81 * fields can be used to pass a memory map to the guest. The
82 * memory map is optional and so guests that understand version 1
83 * of the structure must check that memmap_entries is non-zero
84 * before trying to read the memory map.
85 */
86#define XEN_HVM_START_MAGIC_VALUE 0x336ec578
87
88/*
89 * The values used in the type field of the memory map table entries are
90 * defined below and match the Address Range Types as defined in the "System
91 * Address Map Interfaces" section of the ACPI Specification. Please refer to
92 * section 15 in version 6.2 of the ACPI spec: http://uefi.org/specifications
93 */
94#define XEN_HVM_MEMMAP_TYPE_RAM 1
95#define XEN_HVM_MEMMAP_TYPE_RESERVED 2
96#define XEN_HVM_MEMMAP_TYPE_ACPI 3
97#define XEN_HVM_MEMMAP_TYPE_NVS 4
98#define XEN_HVM_MEMMAP_TYPE_UNUSABLE 5
99#define XEN_HVM_MEMMAP_TYPE_DISABLED 6
100#define XEN_HVM_MEMMAP_TYPE_PMEM 7
101
102/*
103 * C representation of the x86/HVM start info layout.
104 *
105 * The canonical definition of this layout is above, this is just a way to
106 * represent the layout described there using C types.
107 */
108struct hvm_start_info {
109 uint32_t magic; /* Contains the magic value 0x336ec578 */
110 /* ("xEn3" with the 0x80 bit of the "E" set).*/
111 uint32_t version; /* Version of this structure. */
112 uint32_t flags; /* SIF_xxx flags. */
113 uint32_t nr_modules; /* Number of modules passed to the kernel. */
114 uint64_t modlist_paddr; /* Physical address of an array of */
115 /* hvm_modlist_entry. */
116 uint64_t cmdline_paddr; /* Physical address of the command line. */
117 uint64_t rsdp_paddr; /* Physical address of the RSDP ACPI data */
118 /* structure. */
119 /* All following fields only present in version 1 and newer */
120 uint64_t memmap_paddr; /* Physical address of an array of */
121 /* hvm_memmap_table_entry. */
122 uint32_t memmap_entries; /* Number of entries in the memmap table. */
123 /* Value will be zero if there is no memory */
124 /* map being provided. */
125 uint32_t reserved; /* Must be zero. */
126};
127
128struct hvm_modlist_entry {
129 uint64_t paddr; /* Physical address of the module. */
130 uint64_t size; /* Size of the module in bytes. */
131 uint64_t cmdline_paddr; /* Physical address of the command line. */
132 uint64_t reserved;
133};
134
135struct hvm_memmap_table_entry {
136 uint64_t addr; /* Base address of the memory region */
137 uint64_t size; /* Size of the memory region in bytes */
138 uint32_t type; /* Mapping type */
139 uint32_t reserved; /* Must be zero for Version 1. */
140};
141
142#endif /* __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__ */
143

source code of linux/include/xen/interface/hvm/start_info.h