1 /* hvapi.c: Hypervisor API management.
3 * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
5 #include <linux/kernel.h>
6 #include <linux/export.h>
7 #include <linux/init.h>
9 #include <asm/hypervisor.h>
10 #include <asm/oplib.h>
12 /* If the hypervisor indicates that the API setting
13 * calls are unsupported, by returning HV_EBADTRAP or
14 * HV_ENOTSUPPORTED, we assume that API groups with the
15 * PRE_API flag set are major 1 minor 0.
23 #define FLAG_PRE_API 0x00000001
26 static struct api_info api_table[] = {
27 { .group = HV_GRP_SUN4V, .flags = FLAG_PRE_API },
28 { .group = HV_GRP_CORE, .flags = FLAG_PRE_API },
29 { .group = HV_GRP_INTR, },
30 { .group = HV_GRP_SOFT_STATE, },
31 { .group = HV_GRP_TM, },
32 { .group = HV_GRP_PCI, .flags = FLAG_PRE_API },
33 { .group = HV_GRP_LDOM, },
34 { .group = HV_GRP_SVC_CHAN, .flags = FLAG_PRE_API },
35 { .group = HV_GRP_NCS, .flags = FLAG_PRE_API },
36 { .group = HV_GRP_RNG, },
37 { .group = HV_GRP_PBOOT, },
38 { .group = HV_GRP_TPM, },
39 { .group = HV_GRP_SDIO, },
40 { .group = HV_GRP_SDIO_ERR, },
41 { .group = HV_GRP_REBOOT_DATA, },
42 { .group = HV_GRP_NIAG_PERF, .flags = FLAG_PRE_API },
43 { .group = HV_GRP_FIRE_PERF, },
44 { .group = HV_GRP_N2_CPU, },
45 { .group = HV_GRP_NIU, },
46 { .group = HV_GRP_VF_CPU, },
47 { .group = HV_GRP_KT_CPU, },
48 { .group = HV_GRP_VT_CPU, },
49 { .group = HV_GRP_T5_CPU, },
50 { .group = HV_GRP_DIAG, .flags = FLAG_PRE_API },
51 { .group = HV_GRP_M7_PERF, },
54 static DEFINE_SPINLOCK(hvapi_lock);
56 static struct api_info *__get_info(unsigned long group)
60 for (i = 0; i < ARRAY_SIZE(api_table); i++) {
61 if (api_table[i].group == group)
67 static void __get_ref(struct api_info *p)
72 static void __put_ref(struct api_info *p)
74 if (--p->refcnt == 0) {
77 sun4v_set_version(p->group, 0, 0, &ignore);
78 p->major = p->minor = 0;
82 /* Register a hypervisor API specification. It indicates the
83 * API group and desired major+minor.
85 * If an existing API registration exists '0' (success) will
86 * be returned if it is compatible with the one being registered.
87 * Otherwise a negative error code will be returned.
89 * Otherwise an attempt will be made to negotiate the requested
90 * API group/major/minor with the hypervisor, and errors returned
91 * if that does not succeed.
93 int sun4v_hvapi_register(unsigned long group, unsigned long major,
100 spin_lock_irqsave(&hvapi_lock, flags);
101 p = __get_info(group);
106 if (p->major == major) {
111 unsigned long actual_minor;
112 unsigned long hv_ret;
114 hv_ret = sun4v_set_version(group, major, *minor,
117 if (hv_ret == HV_EOK) {
118 *minor = actual_minor;
120 p->minor = actual_minor;
122 } else if (hv_ret == HV_EBADTRAP ||
123 hv_ret == HV_ENOTSUPPORTED) {
124 if (p->flags & FLAG_PRE_API) {
138 spin_unlock_irqrestore(&hvapi_lock, flags);
142 EXPORT_SYMBOL(sun4v_hvapi_register);
144 void sun4v_hvapi_unregister(unsigned long group)
149 spin_lock_irqsave(&hvapi_lock, flags);
150 p = __get_info(group);
153 spin_unlock_irqrestore(&hvapi_lock, flags);
155 EXPORT_SYMBOL(sun4v_hvapi_unregister);
157 int sun4v_hvapi_get(unsigned long group,
158 unsigned long *major,
159 unsigned long *minor)
165 spin_lock_irqsave(&hvapi_lock, flags);
167 p = __get_info(group);
168 if (p && p->refcnt) {
173 spin_unlock_irqrestore(&hvapi_lock, flags);
177 EXPORT_SYMBOL(sun4v_hvapi_get);
179 void __init sun4v_hvapi_init(void)
181 unsigned long group, major, minor;
183 group = HV_GRP_SUN4V;
186 if (sun4v_hvapi_register(group, major, &minor))
192 if (sun4v_hvapi_register(group, major, &minor))
198 prom_printf("HVAPI: Cannot register API group "
199 "%lx with major(%lu) minor(%lu)\n",
200 group, major, minor);