1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * AMD SEV header common between the guest and the hypervisor.
4  *
5  * Author: Brijesh Singh <brijesh.singh@amd.com>
6  */
7 
8 #ifndef __ASM_X86_SEV_COMMON_H
9 #define __ASM_X86_SEV_COMMON_H
10 
11 #define GHCB_MSR_INFO_POS		0
12 #define GHCB_DATA_LOW			12
13 #define GHCB_MSR_INFO_MASK		(BIT_ULL(GHCB_DATA_LOW) - 1)
14 
15 #define GHCB_DATA(v)			\
16 	(((unsigned long)(v) & ~GHCB_MSR_INFO_MASK) >> GHCB_DATA_LOW)
17 
18 /* SEV Information Request/Response */
19 #define GHCB_MSR_SEV_INFO_RESP		0x001
20 #define GHCB_MSR_SEV_INFO_REQ		0x002
21 
22 #define GHCB_MSR_SEV_INFO(_max, _min, _cbit)	\
23 	/* GHCBData[63:48] */			\
24 	((((_max) & 0xffff) << 48) |		\
25 	 /* GHCBData[47:32] */			\
26 	 (((_min) & 0xffff) << 32) |		\
27 	 /* GHCBData[31:24] */			\
28 	 (((_cbit) & 0xff)  << 24) |		\
29 	 GHCB_MSR_SEV_INFO_RESP)
30 
31 #define GHCB_MSR_INFO(v)		((v) & 0xfffUL)
32 #define GHCB_MSR_PROTO_MAX(v)		(((v) >> 48) & 0xffff)
33 #define GHCB_MSR_PROTO_MIN(v)		(((v) >> 32) & 0xffff)
34 
35 /* CPUID Request/Response */
36 #define GHCB_MSR_CPUID_REQ		0x004
37 #define GHCB_MSR_CPUID_RESP		0x005
38 #define GHCB_MSR_CPUID_FUNC_POS		32
39 #define GHCB_MSR_CPUID_FUNC_MASK	0xffffffff
40 #define GHCB_MSR_CPUID_VALUE_POS	32
41 #define GHCB_MSR_CPUID_VALUE_MASK	0xffffffff
42 #define GHCB_MSR_CPUID_REG_POS		30
43 #define GHCB_MSR_CPUID_REG_MASK		0x3
44 #define GHCB_CPUID_REQ_EAX		0
45 #define GHCB_CPUID_REQ_EBX		1
46 #define GHCB_CPUID_REQ_ECX		2
47 #define GHCB_CPUID_REQ_EDX		3
48 #define GHCB_CPUID_REQ(fn, reg)				\
49 	/* GHCBData[11:0] */				\
50 	(GHCB_MSR_CPUID_REQ |				\
51 	/* GHCBData[31:12] */				\
52 	(((unsigned long)(reg) & 0x3) << 30) |		\
53 	/* GHCBData[63:32] */				\
54 	(((unsigned long)fn) << 32))
55 
56 /* AP Reset Hold */
57 #define GHCB_MSR_AP_RESET_HOLD_REQ	0x006
58 #define GHCB_MSR_AP_RESET_HOLD_RESP	0x007
59 
60 /* GHCB GPA Register */
61 #define GHCB_MSR_REG_GPA_REQ		0x012
62 #define GHCB_MSR_REG_GPA_REQ_VAL(v)			\
63 	/* GHCBData[63:12] */				\
64 	(((u64)((v) & GENMASK_ULL(51, 0)) << 12) |	\
65 	/* GHCBData[11:0] */				\
66 	GHCB_MSR_REG_GPA_REQ)
67 
68 #define GHCB_MSR_REG_GPA_RESP		0x013
69 #define GHCB_MSR_REG_GPA_RESP_VAL(v)			\
70 	/* GHCBData[63:12] */				\
71 	(((u64)(v) & GENMASK_ULL(63, 12)) >> 12)
72 
73 /*
74  * SNP Page State Change Operation
75  *
76  * GHCBData[55:52] - Page operation:
77  *   0x0001	Page assignment, Private
78  *   0x0002	Page assignment, Shared
79  */
80 enum psc_op {
81 	SNP_PAGE_STATE_PRIVATE = 1,
82 	SNP_PAGE_STATE_SHARED,
83 };
84 
85 #define GHCB_MSR_PSC_REQ		0x014
86 #define GHCB_MSR_PSC_REQ_GFN(gfn, op)			\
87 	/* GHCBData[55:52] */				\
88 	(((u64)((op) & 0xf) << 52) |			\
89 	/* GHCBData[51:12] */				\
90 	((u64)((gfn) & GENMASK_ULL(39, 0)) << 12) |	\
91 	/* GHCBData[11:0] */				\
92 	GHCB_MSR_PSC_REQ)
93 
94 #define GHCB_MSR_PSC_RESP		0x015
95 #define GHCB_MSR_PSC_RESP_VAL(val)			\
96 	/* GHCBData[63:32] */				\
97 	(((u64)(val) & GENMASK_ULL(63, 32)) >> 32)
98 
99 /* GHCB Hypervisor Feature Request/Response */
100 #define GHCB_MSR_HV_FT_REQ		0x080
101 #define GHCB_MSR_HV_FT_RESP		0x081
102 #define GHCB_MSR_HV_FT_RESP_VAL(v)			\
103 	/* GHCBData[63:12] */				\
104 	(((u64)(v) & GENMASK_ULL(63, 12)) >> 12)
105 
106 #define GHCB_HV_FT_SNP			BIT_ULL(0)
107 #define GHCB_HV_FT_SNP_AP_CREATION	BIT_ULL(1)
108 
109 /*
110  * SNP Page State Change NAE event
111  *   The VMGEXIT_PSC_MAX_ENTRY determines the size of the PSC structure, which
112  *   is a local stack variable in set_pages_state(). Do not increase this value
113  *   without evaluating the impact to stack usage.
114  */
115 #define VMGEXIT_PSC_MAX_ENTRY		64
116 
117 struct psc_hdr {
118 	u16 cur_entry;
119 	u16 end_entry;
120 	u32 reserved;
121 } __packed;
122 
123 struct psc_entry {
124 	u64	cur_page	: 12,
125 		gfn		: 40,
126 		operation	: 4,
127 		pagesize	: 1,
128 		reserved	: 7;
129 } __packed;
130 
131 struct snp_psc_desc {
132 	struct psc_hdr hdr;
133 	struct psc_entry entries[VMGEXIT_PSC_MAX_ENTRY];
134 } __packed;
135 
136 #define GHCB_MSR_TERM_REQ		0x100
137 #define GHCB_MSR_TERM_REASON_SET_POS	12
138 #define GHCB_MSR_TERM_REASON_SET_MASK	0xf
139 #define GHCB_MSR_TERM_REASON_POS	16
140 #define GHCB_MSR_TERM_REASON_MASK	0xff
141 
142 #define GHCB_SEV_TERM_REASON(reason_set, reason_val)	\
143 	/* GHCBData[15:12] */				\
144 	(((((u64)reason_set) &  0xf) << 12) |		\
145 	 /* GHCBData[23:16] */				\
146 	((((u64)reason_val) & 0xff) << 16))
147 
148 /* Error codes from reason set 0 */
149 #define SEV_TERM_SET_GEN		0
150 #define GHCB_SEV_ES_GEN_REQ		0
151 #define GHCB_SEV_ES_PROT_UNSUPPORTED	1
152 #define GHCB_SNP_UNSUPPORTED		2
153 
154 /* Linux-specific reason codes (used with reason set 1) */
155 #define SEV_TERM_SET_LINUX		1
156 #define GHCB_TERM_REGISTER		0	/* GHCB GPA registration failure */
157 #define GHCB_TERM_PSC			1	/* Page State Change failure */
158 #define GHCB_TERM_PVALIDATE		2	/* Pvalidate failure */
159 #define GHCB_TERM_NOT_VMPL0		3	/* SNP guest is not running at VMPL-0 */
160 #define GHCB_TERM_CPUID			4	/* CPUID-validation failure */
161 #define GHCB_TERM_CPUID_HV		5	/* CPUID failure during hypervisor fallback */
162 
163 #define GHCB_RESP_CODE(v)		((v) & GHCB_MSR_INFO_MASK)
164 
165 /*
166  * Error codes related to GHCB input that can be communicated back to the guest
167  * by setting the lower 32-bits of the GHCB SW_EXITINFO1 field to 2.
168  */
169 #define GHCB_ERR_NOT_REGISTERED		1
170 #define GHCB_ERR_INVALID_USAGE		2
171 #define GHCB_ERR_INVALID_SCRATCH_AREA	3
172 #define GHCB_ERR_MISSING_INPUT		4
173 #define GHCB_ERR_INVALID_INPUT		5
174 #define GHCB_ERR_INVALID_EVENT		6
175 
176 #endif
177