xref: /openbmc/qemu/include/hw/xen/interface/features.h (revision 8acf8650)
1 /******************************************************************************
2  * features.h
3  *
4  * Feature flags, reported by XENVER_get_features.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to
8  * deal in the Software without restriction, including without limitation the
9  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10  * sell copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  *
24  * Copyright (c) 2006, Keir Fraser <keir@xensource.com>
25  */
26 
27 #ifndef __XEN_PUBLIC_FEATURES_H__
28 #define __XEN_PUBLIC_FEATURES_H__
29 
30 /*
31  * `incontents 200 elfnotes_features XEN_ELFNOTE_FEATURES
32  *
33  * The list of all the features the guest supports. They are set by
34  * parsing the XEN_ELFNOTE_FEATURES and XEN_ELFNOTE_SUPPORTED_FEATURES
35  * string. The format is the  feature names (as given here without the
36  * "XENFEAT_" prefix) separated by '|' characters.
37  * If a feature is required for the kernel to function then the feature name
38  * must be preceded by a '!' character.
39  *
40  * Note that if XEN_ELFNOTE_SUPPORTED_FEATURES is used, then in the
41  * XENFEAT_dom0 MUST be set if the guest is to be booted as dom0,
42  */
43 
44 /*
45  * If set, the guest does not need to write-protect its pagetables, and can
46  * update them via direct writes.
47  */
48 #define XENFEAT_writable_page_tables       0
49 
50 /*
51  * If set, the guest does not need to write-protect its segment descriptor
52  * tables, and can update them via direct writes.
53  */
54 #define XENFEAT_writable_descriptor_tables 1
55 
56 /*
57  * If set, translation between the guest's 'pseudo-physical' address space
58  * and the host's machine address space are handled by the hypervisor. In this
59  * mode the guest does not need to perform phys-to/from-machine translations
60  * when performing page table operations.
61  */
62 #define XENFEAT_auto_translated_physmap    2
63 
64 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
65 #define XENFEAT_supervisor_mode_kernel     3
66 
67 /*
68  * If set, the guest does not need to allocate x86 PAE page directories
69  * below 4GB. This flag is usually implied by auto_translated_physmap.
70  */
71 #define XENFEAT_pae_pgdir_above_4gb        4
72 
73 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
74 #define XENFEAT_mmu_pt_update_preserve_ad  5
75 
76 /* x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall? */
77 #define XENFEAT_highmem_assist             6
78 
79 /*
80  * If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel
81  * available pte bits.
82  */
83 #define XENFEAT_gnttab_map_avail_bits      7
84 
85 /* x86: Does this Xen host support the HVM callback vector type? */
86 #define XENFEAT_hvm_callback_vector        8
87 
88 /* x86: pvclock algorithm is safe to use on HVM */
89 #define XENFEAT_hvm_safe_pvclock           9
90 
91 /* x86: pirq can be used by HVM guests */
92 #define XENFEAT_hvm_pirqs                 10
93 
94 /* operation as Dom0 is supported */
95 #define XENFEAT_dom0                      11
96 
97 /* Xen also maps grant references at pfn = mfn.
98  * This feature flag is deprecated and should not be used.
99 #define XENFEAT_grant_map_identity        12
100  */
101 
102 /* Guest can use XENMEMF_vnode to specify virtual node for memory op. */
103 #define XENFEAT_memory_op_vnode_supported 13
104 
105 /* arm: Hypervisor supports ARM SMC calling convention. */
106 #define XENFEAT_ARM_SMCCC_supported       14
107 
108 /*
109  * x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP
110  * must be located in lower 1MB, as required by ACPI Specification for IA-PC
111  * systems.
112  * This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains
113  * the "linux" string.
114  */
115 #define XENFEAT_linux_rsdp_unrestricted   15
116 
117 /*
118  * A direct-mapped (or 1:1 mapped) domain is a domain for which its
119  * local pages have gfn == mfn. If a domain is direct-mapped,
120  * XENFEAT_direct_mapped is set; otherwise XENFEAT_not_direct_mapped
121  * is set.
122  *
123  * If neither flag is set (e.g. older Xen releases) the assumptions are:
124  * - not auto_translated domains (x86 only) are always direct-mapped
125  * - on x86, auto_translated domains are not direct-mapped
126  * - on ARM, Dom0 is direct-mapped, DomUs are not
127  */
128 #define XENFEAT_not_direct_mapped         16
129 #define XENFEAT_direct_mapped             17
130 
131 #define XENFEAT_NR_SUBMAPS 1
132 
133 #endif /* __XEN_PUBLIC_FEATURES_H__ */
134 
135 /*
136  * Local variables:
137  * mode: C
138  * c-file-style: "BSD"
139  * c-basic-offset: 4
140  * tab-width: 4
141  * indent-tabs-mode: nil
142  * End:
143  */
144