Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[linux-2.6] / arch / sparc / kernel / sstate.c
1 /* sstate.c: System soft state support.
2  *
3  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4  */
5
6 #include <linux/kernel.h>
7 #include <linux/notifier.h>
8 #include <linux/reboot.h>
9 #include <linux/init.h>
10
11 #include <asm/hypervisor.h>
12 #include <asm/spitfire.h>
13 #include <asm/oplib.h>
14 #include <asm/head.h>
15 #include <asm/io.h>
16
17 static int hv_supports_soft_state;
18
19 static unsigned long kimage_addr_to_ra(const char *p)
20 {
21         unsigned long val = (unsigned long) p;
22
23         return kern_base + (val - KERNBASE);
24 }
25
26 static void do_set_sstate(unsigned long state, const char *msg)
27 {
28         unsigned long err;
29
30         if (!hv_supports_soft_state)
31                 return;
32
33         err = sun4v_mach_set_soft_state(state, kimage_addr_to_ra(msg));
34         if (err) {
35                 printk(KERN_WARNING "SSTATE: Failed to set soft-state to "
36                        "state[%lx] msg[%s], err=%lu\n",
37                        state, msg, err);
38         }
39 }
40
41 static const char booting_msg[32] __attribute__((aligned(32))) =
42         "Linux booting";
43 static const char running_msg[32] __attribute__((aligned(32))) =
44         "Linux running";
45 static const char halting_msg[32] __attribute__((aligned(32))) =
46         "Linux halting";
47 static const char poweroff_msg[32] __attribute__((aligned(32))) =
48         "Linux powering off";
49 static const char rebooting_msg[32] __attribute__((aligned(32))) =
50         "Linux rebooting";
51 static const char panicing_msg[32] __attribute__((aligned(32))) =
52         "Linux panicing";
53
54 static int sstate_reboot_call(struct notifier_block *np, unsigned long type, void *_unused)
55 {
56         const char *msg;
57
58         switch (type) {
59         case SYS_DOWN:
60         default:
61                 msg = rebooting_msg;
62                 break;
63
64         case SYS_HALT:
65                 msg = halting_msg;
66                 break;
67
68         case SYS_POWER_OFF:
69                 msg = poweroff_msg;
70                 break;
71         }
72
73         do_set_sstate(HV_SOFT_STATE_TRANSITION, msg);
74
75         return NOTIFY_OK;
76 }
77
78 static struct notifier_block sstate_reboot_notifier = {
79         .notifier_call = sstate_reboot_call,
80 };
81
82 static int sstate_panic_event(struct notifier_block *n, unsigned long event, void *ptr)
83 {
84         do_set_sstate(HV_SOFT_STATE_TRANSITION, panicing_msg);
85
86         return NOTIFY_DONE;
87 }
88
89 static struct notifier_block sstate_panic_block = {
90         .notifier_call  =       sstate_panic_event,
91         .priority       =       INT_MAX,
92 };
93
94 static int __init sstate_init(void)
95 {
96         unsigned long major, minor;
97
98         if (tlb_type != hypervisor)
99                 return 0;
100
101         major = 1;
102         minor = 0;
103         if (sun4v_hvapi_register(HV_GRP_SOFT_STATE, major, &minor))
104                 return 0;
105
106         hv_supports_soft_state = 1;
107
108         prom_sun4v_guest_soft_state();
109
110         do_set_sstate(HV_SOFT_STATE_TRANSITION, booting_msg);
111
112         atomic_notifier_chain_register(&panic_notifier_list,
113                                        &sstate_panic_block);
114         register_reboot_notifier(&sstate_reboot_notifier);
115
116         return 0;
117 }
118
119 core_initcall(sstate_init);
120
121 static int __init sstate_running(void)
122 {
123         do_set_sstate(HV_SOFT_STATE_NORMAL, running_msg);
124         return 0;
125 }
126
127 late_initcall(sstate_running);