xref: /openbmc/qemu/include/hw/xen/start_info.h (revision 6016b7b4)
1 /*
2  * Permission is hereby granted, free of charge, to any person obtaining a copy
3  * of this software and associated documentation files (the "Software"), to
4  * deal in the Software without restriction, including without limitation the
5  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
6  * sell copies of the Software, and to permit persons to whom the Software is
7  * furnished to do so, subject to the following conditions:
8  *
9  * The above copyright notice and this permission notice shall be included in
10  * all copies or substantial portions of the Software.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
15  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
16  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
17  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
18  * DEALINGS IN THE SOFTWARE.
19  *
20  * Copyright (c) 2016, Citrix Systems, Inc.
21  */
22 
23 #ifndef XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H
24 #define XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H
25 
26 /*
27  * Start of day structure passed to PVH guests and to HVM guests in %ebx.
28  *
29  * NOTE: nothing will be loaded at physical address 0, so a 0 value in any
30  * of the address fields should be treated as not present.
31  *
32  *  0 +----------------+
33  *    | magic          | Contains the magic value XEN_HVM_START_MAGIC_VALUE
34  *    |                | ("xEn3" with the 0x80 bit of the "E" set).
35  *  4 +----------------+
36  *    | version        | Version of this structure. Current version is 1. New
37  *    |                | versions are guaranteed to be backwards-compatible.
38  *  8 +----------------+
39  *    | flags          | SIF_xxx flags.
40  * 12 +----------------+
41  *    | nr_modules     | Number of modules passed to the kernel.
42  * 16 +----------------+
43  *    | modlist_paddr  | Physical address of an array of modules
44  *    |                | (layout of the structure below).
45  * 24 +----------------+
46  *    | cmdline_paddr  | Physical address of the command line,
47  *    |                | a zero-terminated ASCII string.
48  * 32 +----------------+
49  *    | rsdp_paddr     | Physical address of the RSDP ACPI data structure.
50  * 40 +----------------+
51  *    | memmap_paddr   | Physical address of the (optional) memory map. Only
52  *    |                | present in version 1 and newer of the structure.
53  * 48 +----------------+
54  *    | memmap_entries | Number of entries in the memory map table. Only
55  *    |                | present in version 1 and newer of the structure.
56  *    |                | Zero if there is no memory map being provided.
57  * 52 +----------------+
58  *    | reserved       | Version 1 and newer only.
59  * 56 +----------------+
60  *
61  * The layout of each entry in the module structure is the following:
62  *
63  *  0 +----------------+
64  *    | paddr          | Physical address of the module.
65  *  8 +----------------+
66  *    | size           | Size of the module in bytes.
67  * 16 +----------------+
68  *    | cmdline_paddr  | Physical address of the command line,
69  *    |                | a zero-terminated ASCII string.
70  * 24 +----------------+
71  *    | reserved       |
72  * 32 +----------------+
73  *
74  * The layout of each entry in the memory map table is as follows:
75  *
76  *  0 +----------------+
77  *    | addr           | Base address
78  *  8 +----------------+
79  *    | size           | Size of mapping in bytes
80  * 16 +----------------+
81  *    | type           | Type of mapping as defined between the hypervisor
82  *    |                | and guest it's starting. E820_TYPE_xxx, for example.
83  * 20 +----------------|
84  *    | reserved       |
85  * 24 +----------------+
86  *
87  * The address and sizes are always a 64bit little endian unsigned integer.
88  *
89  * NB: Xen on x86 will always try to place all the data below the 4GiB
90  * boundary.
91  *
92  * Version numbers of the hvm_start_info structure have evolved like this:
93  *
94  * Version 0:
95  *
96  * Version 1:   Added the memmap_paddr/memmap_entries fields (plus 4 bytes of
97  *              padding) to the end of the hvm_start_info struct. These new
98  *              fields can be used to pass a memory map to the guest. The
99  *              memory map is optional and so guests that understand version 1
100  *              of the structure must check that memmap_entries is non-zero
101  *              before trying to read the memory map.
102  */
103 #define XEN_HVM_START_MAGIC_VALUE 0x336ec578
104 
105 /*
106  * C representation of the x86/HVM start info layout.
107  *
108  * The canonical definition of this layout is above, this is just a way to
109  * represent the layout described there using C types.
110  */
111 struct hvm_start_info {
112     uint32_t magic;             /* Contains the magic value 0x336ec578       */
113                                 /* ("xEn3" with the 0x80 bit of the "E" set).*/
114     uint32_t version;           /* Version of this structure.                */
115     uint32_t flags;             /* SIF_xxx flags.                            */
116     uint32_t nr_modules;        /* Number of modules passed to the kernel.   */
117     uint64_t modlist_paddr;     /* Physical address of an array of           */
118                                 /* hvm_modlist_entry.                        */
119     uint64_t cmdline_paddr;     /* Physical address of the command line.     */
120     uint64_t rsdp_paddr;        /* Physical address of the RSDP ACPI data    */
121                                 /* structure.                                */
122     uint64_t memmap_paddr;      /* Physical address of an array of           */
123                                 /* hvm_memmap_table_entry. Only present in   */
124                                 /* version 1 and newer of the structure      */
125     uint32_t memmap_entries;    /* Number of entries in the memmap table.    */
126                                 /* Only present in version 1 and newer of    */
127                                 /* the structure. Value will be zero if      */
128                                 /* there is no memory map being provided.    */
129     uint32_t reserved;
130 };
131 
132 struct hvm_modlist_entry {
133     uint64_t paddr;             /* Physical address of the module.           */
134     uint64_t size;              /* Size of the module in bytes.              */
135     uint64_t cmdline_paddr;     /* Physical address of the command line.     */
136     uint64_t reserved;
137 };
138 
139 struct hvm_memmap_table_entry {
140     uint64_t addr;              /* Base address of the memory region         */
141     uint64_t size;              /* Size of the memory region in bytes        */
142     uint32_t type;              /* Mapping type                              */
143     uint32_t reserved;
144 };
145 
146 #endif /* XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H */
147