]>
Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
c7754d46 DM |
2 | /* hvapi.c: Hypervisor API management. |
3 | * | |
4 | * Copyright (C) 2007 David S. Miller <davem@davemloft.net> | |
5 | */ | |
6 | #include <linux/kernel.h> | |
066bcaca | 7 | #include <linux/export.h> |
c7754d46 | 8 | #include <linux/init.h> |
c7754d46 DM |
9 | |
10 | #include <asm/hypervisor.h> | |
11 | #include <asm/oplib.h> | |
12 | ||
13 | /* If the hypervisor indicates that the API setting | |
14 | * calls are unsupported, by returning HV_EBADTRAP or | |
15 | * HV_ENOTSUPPORTED, we assume that API groups with the | |
16 | * PRE_API flag set are major 1 minor 0. | |
17 | */ | |
18 | struct api_info { | |
19 | unsigned long group; | |
20 | unsigned long major; | |
21 | unsigned long minor; | |
22 | unsigned int refcnt; | |
23 | unsigned int flags; | |
24 | #define FLAG_PRE_API 0x00000001 | |
25 | }; | |
26 | ||
27 | static struct api_info api_table[] = { | |
28 | { .group = HV_GRP_SUN4V, .flags = FLAG_PRE_API }, | |
29 | { .group = HV_GRP_CORE, .flags = FLAG_PRE_API }, | |
30 | { .group = HV_GRP_INTR, }, | |
31 | { .group = HV_GRP_SOFT_STATE, }, | |
e2eb9f81 | 32 | { .group = HV_GRP_TM, }, |
c7754d46 DM |
33 | { .group = HV_GRP_PCI, .flags = FLAG_PRE_API }, |
34 | { .group = HV_GRP_LDOM, }, | |
35 | { .group = HV_GRP_SVC_CHAN, .flags = FLAG_PRE_API }, | |
36 | { .group = HV_GRP_NCS, .flags = FLAG_PRE_API }, | |
432e8765 | 37 | { .group = HV_GRP_RNG, }, |
e2eb9f81 DM |
38 | { .group = HV_GRP_PBOOT, }, |
39 | { .group = HV_GRP_TPM, }, | |
40 | { .group = HV_GRP_SDIO, }, | |
41 | { .group = HV_GRP_SDIO_ERR, }, | |
42 | { .group = HV_GRP_REBOOT_DATA, }, | |
f0248c15 | 43 | { .group = HV_GRP_ATU, .flags = FLAG_PRE_API }, |
c7754d46 DM |
44 | { .group = HV_GRP_NIAG_PERF, .flags = FLAG_PRE_API }, |
45 | { .group = HV_GRP_FIRE_PERF, }, | |
432e8765 DM |
46 | { .group = HV_GRP_N2_CPU, }, |
47 | { .group = HV_GRP_NIU, }, | |
48 | { .group = HV_GRP_VF_CPU, }, | |
15e3608d | 49 | { .group = HV_GRP_KT_CPU, }, |
8c79bfa5 | 50 | { .group = HV_GRP_VT_CPU, }, |
05aa1651 | 51 | { .group = HV_GRP_T5_CPU, }, |
c7754d46 | 52 | { .group = HV_GRP_DIAG, .flags = FLAG_PRE_API }, |
b5aff55d | 53 | { .group = HV_GRP_M7_PERF, }, |
c7754d46 DM |
54 | }; |
55 | ||
56 | static DEFINE_SPINLOCK(hvapi_lock); | |
57 | ||
58 | static struct api_info *__get_info(unsigned long group) | |
59 | { | |
60 | int i; | |
61 | ||
62 | for (i = 0; i < ARRAY_SIZE(api_table); i++) { | |
63 | if (api_table[i].group == group) | |
64 | return &api_table[i]; | |
65 | } | |
66 | return NULL; | |
67 | } | |
68 | ||
69 | static void __get_ref(struct api_info *p) | |
70 | { | |
71 | p->refcnt++; | |
72 | } | |
73 | ||
74 | static void __put_ref(struct api_info *p) | |
75 | { | |
76 | if (--p->refcnt == 0) { | |
77 | unsigned long ignore; | |
78 | ||
79 | sun4v_set_version(p->group, 0, 0, &ignore); | |
80 | p->major = p->minor = 0; | |
81 | } | |
82 | } | |
83 | ||
84 | /* Register a hypervisor API specification. It indicates the | |
85 | * API group and desired major+minor. | |
86 | * | |
87 | * If an existing API registration exists '0' (success) will | |
88 | * be returned if it is compatible with the one being registered. | |
89 | * Otherwise a negative error code will be returned. | |
90 | * | |
91 | * Otherwise an attempt will be made to negotiate the requested | |
92 | * API group/major/minor with the hypervisor, and errors returned | |
93 | * if that does not succeed. | |
94 | */ | |
95 | int sun4v_hvapi_register(unsigned long group, unsigned long major, | |
96 | unsigned long *minor) | |
97 | { | |
98 | struct api_info *p; | |
99 | unsigned long flags; | |
100 | int ret; | |
101 | ||
102 | spin_lock_irqsave(&hvapi_lock, flags); | |
103 | p = __get_info(group); | |
104 | ret = -EINVAL; | |
105 | if (p) { | |
106 | if (p->refcnt) { | |
107 | ret = -EINVAL; | |
108 | if (p->major == major) { | |
109 | *minor = p->minor; | |
110 | ret = 0; | |
111 | } | |
112 | } else { | |
113 | unsigned long actual_minor; | |
114 | unsigned long hv_ret; | |
115 | ||
116 | hv_ret = sun4v_set_version(group, major, *minor, | |
117 | &actual_minor); | |
118 | ret = -EINVAL; | |
119 | if (hv_ret == HV_EOK) { | |
120 | *minor = actual_minor; | |
121 | p->major = major; | |
122 | p->minor = actual_minor; | |
123 | ret = 0; | |
124 | } else if (hv_ret == HV_EBADTRAP || | |
36b48973 | 125 | hv_ret == HV_ENOTSUPPORTED) { |
c7754d46 DM |
126 | if (p->flags & FLAG_PRE_API) { |
127 | if (major == 1) { | |
128 | p->major = 1; | |
129 | p->minor = 0; | |
130 | *minor = 0; | |
131 | ret = 0; | |
132 | } | |
133 | } | |
134 | } | |
135 | } | |
136 | ||
137 | if (ret == 0) | |
138 | __get_ref(p); | |
139 | } | |
140 | spin_unlock_irqrestore(&hvapi_lock, flags); | |
141 | ||
142 | return ret; | |
143 | } | |
144 | EXPORT_SYMBOL(sun4v_hvapi_register); | |
145 | ||
146 | void sun4v_hvapi_unregister(unsigned long group) | |
147 | { | |
148 | struct api_info *p; | |
149 | unsigned long flags; | |
150 | ||
151 | spin_lock_irqsave(&hvapi_lock, flags); | |
152 | p = __get_info(group); | |
153 | if (p) | |
154 | __put_ref(p); | |
155 | spin_unlock_irqrestore(&hvapi_lock, flags); | |
156 | } | |
157 | EXPORT_SYMBOL(sun4v_hvapi_unregister); | |
158 | ||
159 | int sun4v_hvapi_get(unsigned long group, | |
160 | unsigned long *major, | |
161 | unsigned long *minor) | |
162 | { | |
163 | struct api_info *p; | |
164 | unsigned long flags; | |
165 | int ret; | |
166 | ||
167 | spin_lock_irqsave(&hvapi_lock, flags); | |
168 | ret = -EINVAL; | |
169 | p = __get_info(group); | |
170 | if (p && p->refcnt) { | |
171 | *major = p->major; | |
172 | *minor = p->minor; | |
173 | ret = 0; | |
174 | } | |
175 | spin_unlock_irqrestore(&hvapi_lock, flags); | |
176 | ||
177 | return ret; | |
178 | } | |
179 | EXPORT_SYMBOL(sun4v_hvapi_get); | |
180 | ||
181 | void __init sun4v_hvapi_init(void) | |
182 | { | |
183 | unsigned long group, major, minor; | |
184 | ||
185 | group = HV_GRP_SUN4V; | |
186 | major = 1; | |
187 | minor = 0; | |
188 | if (sun4v_hvapi_register(group, major, &minor)) | |
189 | goto bad; | |
190 | ||
191 | group = HV_GRP_CORE; | |
192 | major = 1; | |
8536e02e | 193 | minor = 6; |
c7754d46 DM |
194 | if (sun4v_hvapi_register(group, major, &minor)) |
195 | goto bad; | |
196 | ||
197 | return; | |
198 | ||
199 | bad: | |
200 | prom_printf("HVAPI: Cannot register API group " | |
5da444aa | 201 | "%lx with major(%lu) minor(%lu)\n", |
c7754d46 DM |
202 | group, major, minor); |
203 | prom_halt(); | |
204 | } |