arch/sparc64/kernel/sstate.c

   1 /* sstate.c: System soft state support.
   2  *
   3  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/notifier.h>
   8 #include <linux/init.h>
   9
  10 #include <asm/hypervisor.h>
  11 #include <asm/sstate.h>
  12 #include <asm/oplib.h>
  13 #include <asm/head.h>
  14 #include <asm/io.h>
  15
  16 static int hv_supports_soft_state;
  17
  18 static unsigned long kimage_addr_to_ra(const char *p)
  19 {
  20         unsigned long val = (unsigned long) p;
  21
  22         return kern_base + (val - KERNBASE);
  23 }
  24
  25 static void do_set_sstate(unsigned long state, const char *msg)
  26 {
  27         unsigned long err;
  28
  29         if (!hv_supports_soft_state)
  30                 return;
  31
  32         err = sun4v_mach_set_soft_state(state, kimage_addr_to_ra(msg));
  33         if (err) {
  34                 printk(KERN_WARNING "SSTATE: Failed to set soft-state to "
  35                        "state[%lx] msg[%s], err=%lu\n",
  36                        state, msg, err);
  37         }
  38 }
  39
  40 static const char booting_msg[32] __attribute__((aligned(32))) =
  41         "Linux booting";
  42 static const char running_msg[32] __attribute__((aligned(32))) =
  43         "Linux running";
  44 static const char halting_msg[32] __attribute__((aligned(32))) =
  45         "Linux halting";
  46 static const char poweroff_msg[32] __attribute__((aligned(32))) =
  47         "Linux powering off";
  48 static const char rebooting_msg[32] __attribute__((aligned(32))) =
  49         "Linux rebooting";
  50 static const char panicing_msg[32] __attribute__((aligned(32))) =
  51         "Linux panicing";
  52
  53 void sstate_booting(void)
  54 {
  55         do_set_sstate(HV_SOFT_STATE_TRANSITION, booting_msg);
  56 }
  57
  58 void sstate_running(void)
  59 {
  60         do_set_sstate(HV_SOFT_STATE_NORMAL, running_msg);
  61 }
  62
  63 void sstate_halt(void)
  64 {
  65         do_set_sstate(HV_SOFT_STATE_TRANSITION, halting_msg);
  66 }
  67
  68 void sstate_poweroff(void)
  69 {
  70         do_set_sstate(HV_SOFT_STATE_TRANSITION, poweroff_msg);
  71 }
  72
  73 void sstate_reboot(void)
  74 {
  75         do_set_sstate(HV_SOFT_STATE_TRANSITION, rebooting_msg);
  76 }
  77
  78 static int sstate_panic_event(struct notifier_block *n, unsigned long event, void *ptr)
  79 {
  80         do_set_sstate(HV_SOFT_STATE_TRANSITION, panicing_msg);
  81
  82         return NOTIFY_DONE;
  83 }
  84
  85 static struct notifier_block sstate_panic_block = {
  86         .notifier_call  =       sstate_panic_event,
  87         .priority       =       INT_MAX,
  88 };
  89
  90 void __init sun4v_sstate_init(void)
  91 {
  92         unsigned long major, minor;
  93
  94         major = 1;
  95         minor = 0;
  96         if (sun4v_hvapi_register(HV_GRP_SOFT_STATE, major, &minor))
  97                 return;
  98
  99         hv_supports_soft_state = 1;
 100
 101         prom_sun4v_guest_soft_state();
 102         atomic_notifier_chain_register(&panic_notifier_list,
 103                                        &sstate_panic_block);
 104 }