xref: /openbmc/qemu/include/hw/xen/interface/features.h (revision 4921d0a7)
1 /* SPDX-License-Identifier: MIT */
2 /******************************************************************************
3  * features.h
4  *
5  * Feature flags, reported by XENVER_get_features.
6  *
7  * Copyright (c) 2006, Keir Fraser <keir@xensource.com>
8  */
9 
10 #ifndef __XEN_PUBLIC_FEATURES_H__
11 #define __XEN_PUBLIC_FEATURES_H__
12 
13 /*
14  * `incontents 200 elfnotes_features XEN_ELFNOTE_FEATURES
15  *
16  * The list of all the features the guest supports. They are set by
17  * parsing the XEN_ELFNOTE_FEATURES and XEN_ELFNOTE_SUPPORTED_FEATURES
18  * string. The format is the  feature names (as given here without the
19  * "XENFEAT_" prefix) separated by '|' characters.
20  * If a feature is required for the kernel to function then the feature name
21  * must be preceded by a '!' character.
22  *
23  * Note that if XEN_ELFNOTE_SUPPORTED_FEATURES is used, then in the
24  * XENFEAT_dom0 MUST be set if the guest is to be booted as dom0,
25  */
26 
27 /*
28  * If set, the guest does not need to write-protect its pagetables, and can
29  * update them via direct writes.
30  */
31 #define XENFEAT_writable_page_tables       0
32 
33 /*
34  * If set, the guest does not need to write-protect its segment descriptor
35  * tables, and can update them via direct writes.
36  */
37 #define XENFEAT_writable_descriptor_tables 1
38 
39 /*
40  * If set, translation between the guest's 'pseudo-physical' address space
41  * and the host's machine address space are handled by the hypervisor. In this
42  * mode the guest does not need to perform phys-to/from-machine translations
43  * when performing page table operations.
44  */
45 #define XENFEAT_auto_translated_physmap    2
46 
47 /* If set, the guest is running in supervisor mode (e.g., x86 ring 0). */
48 #define XENFEAT_supervisor_mode_kernel     3
49 
50 /*
51  * If set, the guest does not need to allocate x86 PAE page directories
52  * below 4GB. This flag is usually implied by auto_translated_physmap.
53  */
54 #define XENFEAT_pae_pgdir_above_4gb        4
55 
56 /* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */
57 #define XENFEAT_mmu_pt_update_preserve_ad  5
58 
59 /* x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall? */
60 #define XENFEAT_highmem_assist             6
61 
62 /*
63  * If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel
64  * available pte bits.
65  */
66 #define XENFEAT_gnttab_map_avail_bits      7
67 
68 /* x86: Does this Xen host support the HVM callback vector type? */
69 #define XENFEAT_hvm_callback_vector        8
70 
71 /* x86: pvclock algorithm is safe to use on HVM */
72 #define XENFEAT_hvm_safe_pvclock           9
73 
74 /* x86: pirq can be used by HVM guests */
75 #define XENFEAT_hvm_pirqs                 10
76 
77 /* operation as Dom0 is supported */
78 #define XENFEAT_dom0                      11
79 
80 /* Xen also maps grant references at pfn = mfn.
81  * This feature flag is deprecated and should not be used.
82 #define XENFEAT_grant_map_identity        12
83  */
84 
85 /* Guest can use XENMEMF_vnode to specify virtual node for memory op. */
86 #define XENFEAT_memory_op_vnode_supported 13
87 
88 /* arm: Hypervisor supports ARM SMC calling convention. */
89 #define XENFEAT_ARM_SMCCC_supported       14
90 
91 /*
92  * x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP
93  * must be located in lower 1MB, as required by ACPI Specification for IA-PC
94  * systems.
95  * This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains
96  * the "linux" string.
97  */
98 #define XENFEAT_linux_rsdp_unrestricted   15
99 
100 /*
101  * A direct-mapped (or 1:1 mapped) domain is a domain for which its
102  * local pages have gfn == mfn. If a domain is direct-mapped,
103  * XENFEAT_direct_mapped is set; otherwise XENFEAT_not_direct_mapped
104  * is set.
105  *
106  * If neither flag is set (e.g. older Xen releases) the assumptions are:
107  * - not auto_translated domains (x86 only) are always direct-mapped
108  * - on x86, auto_translated domains are not direct-mapped
109  * - on ARM, Dom0 is direct-mapped, DomUs are not
110  */
111 #define XENFEAT_not_direct_mapped         16
112 #define XENFEAT_direct_mapped             17
113 
114 #define XENFEAT_NR_SUBMAPS 1
115 
116 #endif /* __XEN_PUBLIC_FEATURES_H__ */
117 
118 /*
119  * Local variables:
120  * mode: C
121  * c-file-style: "BSD"
122  * c-basic-offset: 4
123  * tab-width: 4
124  * indent-tabs-mode: nil
125  * End:
126  */
127