1 /* hvapi.c: Hypervisor API management.
3 * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
5 #include <linux/kernel.h>
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/slab.h>
10 #include <asm/hypervisor.h>
11 #include <asm/oplib.h>
12 #include <asm/sstate.h>
14 /* If the hypervisor indicates that the API setting
15 * calls are unsupported, by returning HV_EBADTRAP or
16 * HV_ENOTSUPPORTED, we assume that API groups with the
17 * PRE_API flag set are major 1 minor 0.
25 #define FLAG_PRE_API 0x00000001
28 static struct api_info api_table
[] = {
29 { .group
= HV_GRP_SUN4V
, .flags
= FLAG_PRE_API
},
30 { .group
= HV_GRP_CORE
, .flags
= FLAG_PRE_API
},
31 { .group
= HV_GRP_INTR
, },
32 { .group
= HV_GRP_SOFT_STATE
, },
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
},
37 { .group
= HV_GRP_RNG
, },
38 { .group
= HV_GRP_NIAG_PERF
, .flags
= FLAG_PRE_API
},
39 { .group
= HV_GRP_FIRE_PERF
, },
40 { .group
= HV_GRP_N2_CPU
, },
41 { .group
= HV_GRP_NIU
, },
42 { .group
= HV_GRP_VF_CPU
, },
43 { .group
= HV_GRP_DIAG
, .flags
= FLAG_PRE_API
},
46 static DEFINE_SPINLOCK(hvapi_lock
);
48 static struct api_info
*__get_info(unsigned long group
)
52 for (i
= 0; i
< ARRAY_SIZE(api_table
); i
++) {
53 if (api_table
[i
].group
== group
)
59 static void __get_ref(struct api_info
*p
)
64 static void __put_ref(struct api_info
*p
)
66 if (--p
->refcnt
== 0) {
69 sun4v_set_version(p
->group
, 0, 0, &ignore
);
70 p
->major
= p
->minor
= 0;
74 /* Register a hypervisor API specification. It indicates the
75 * API group and desired major+minor.
77 * If an existing API registration exists '0' (success) will
78 * be returned if it is compatible with the one being registered.
79 * Otherwise a negative error code will be returned.
81 * Otherwise an attempt will be made to negotiate the requested
82 * API group/major/minor with the hypervisor, and errors returned
83 * if that does not succeed.
85 int sun4v_hvapi_register(unsigned long group
, unsigned long major
,
92 spin_lock_irqsave(&hvapi_lock
, flags
);
93 p
= __get_info(group
);
98 if (p
->major
== major
) {
103 unsigned long actual_minor
;
104 unsigned long hv_ret
;
106 hv_ret
= sun4v_set_version(group
, major
, *minor
,
109 if (hv_ret
== HV_EOK
) {
110 *minor
= actual_minor
;
112 p
->minor
= actual_minor
;
114 } else if (hv_ret
== HV_EBADTRAP
||
115 hv_ret
== HV_ENOTSUPPORTED
) {
116 if (p
->flags
& FLAG_PRE_API
) {
130 spin_unlock_irqrestore(&hvapi_lock
, flags
);
134 EXPORT_SYMBOL(sun4v_hvapi_register
);
136 void sun4v_hvapi_unregister(unsigned long group
)
141 spin_lock_irqsave(&hvapi_lock
, flags
);
142 p
= __get_info(group
);
145 spin_unlock_irqrestore(&hvapi_lock
, flags
);
147 EXPORT_SYMBOL(sun4v_hvapi_unregister
);
149 int sun4v_hvapi_get(unsigned long group
,
150 unsigned long *major
,
151 unsigned long *minor
)
157 spin_lock_irqsave(&hvapi_lock
, flags
);
159 p
= __get_info(group
);
160 if (p
&& p
->refcnt
) {
165 spin_unlock_irqrestore(&hvapi_lock
, flags
);
169 EXPORT_SYMBOL(sun4v_hvapi_get
);
171 void __init
sun4v_hvapi_init(void)
173 unsigned long group
, major
, minor
;
175 group
= HV_GRP_SUN4V
;
178 if (sun4v_hvapi_register(group
, major
, &minor
))
184 if (sun4v_hvapi_register(group
, major
, &minor
))
192 prom_printf("HVAPI: Cannot register API group "
193 "%lx with major(%u) minor(%u)\n",
194 group
, major
, minor
);