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 #include "kernel.h" 18 19 static int hv_supports_soft_state; 20 21 static void do_set_sstate(unsigned long state, const char *msg) 22 { 23 unsigned long err; 24 25 if (!hv_supports_soft_state) 26 return; 27 28 err = sun4v_mach_set_soft_state(state, kimage_addr_to_ra(msg)); 29 if (err) { 30 printk(KERN_WARNING "SSTATE: Failed to set soft-state to " 31 "state[%lx] msg[%s], err=%lu\n", 32 state, msg, err); 33 } 34 } 35 36 static const char booting_msg[32] __attribute__((aligned(32))) = 37 "Linux booting"; 38 static const char running_msg[32] __attribute__((aligned(32))) = 39 "Linux running"; 40 static const char halting_msg[32] __attribute__((aligned(32))) = 41 "Linux halting"; 42 static const char poweroff_msg[32] __attribute__((aligned(32))) = 43 "Linux powering off"; 44 static const char rebooting_msg[32] __attribute__((aligned(32))) = 45 "Linux rebooting"; 46 static const char panicking_msg[32] __attribute__((aligned(32))) = 47 "Linux panicking"; 48 49 static int sstate_reboot_call(struct notifier_block *np, unsigned long type, void *_unused) 50 { 51 const char *msg; 52 53 switch (type) { 54 case SYS_DOWN: 55 default: 56 msg = rebooting_msg; 57 break; 58 59 case SYS_HALT: 60 msg = halting_msg; 61 break; 62 63 case SYS_POWER_OFF: 64 msg = poweroff_msg; 65 break; 66 } 67 68 do_set_sstate(HV_SOFT_STATE_TRANSITION, msg); 69 70 return NOTIFY_OK; 71 } 72 73 static struct notifier_block sstate_reboot_notifier = { 74 .notifier_call = sstate_reboot_call, 75 }; 76 77 static int sstate_panic_event(struct notifier_block *n, unsigned long event, void *ptr) 78 { 79 do_set_sstate(HV_SOFT_STATE_TRANSITION, panicking_msg); 80 81 return NOTIFY_DONE; 82 } 83 84 static struct notifier_block sstate_panic_block = { 85 .notifier_call = sstate_panic_event, 86 .priority = INT_MAX, 87 }; 88 89 static int __init sstate_init(void) 90 { 91 unsigned long major, minor; 92 93 if (tlb_type != hypervisor) 94 return 0; 95 96 major = 1; 97 minor = 0; 98 if (sun4v_hvapi_register(HV_GRP_SOFT_STATE, major, &minor)) 99 return 0; 100 101 hv_supports_soft_state = 1; 102 103 prom_sun4v_guest_soft_state(); 104 105 do_set_sstate(HV_SOFT_STATE_TRANSITION, booting_msg); 106 107 atomic_notifier_chain_register(&panic_notifier_list, 108 &sstate_panic_block); 109 register_reboot_notifier(&sstate_reboot_notifier); 110 111 return 0; 112 } 113 114 core_initcall(sstate_init); 115 116 static int __init sstate_running(void) 117 { 118 do_set_sstate(HV_SOFT_STATE_NORMAL, running_msg); 119 return 0; 120 } 121 122 late_initcall(sstate_running); 123