1 /* 2 * Copyright (C) 2007 Atmel Corporation 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 #include <linux/delay.h> 9 #include <linux/kdebug.h> 10 #include <linux/notifier.h> 11 #include <linux/sched.h> 12 #include <linux/sched/debug.h> 13 #include <linux/hardirq.h> 14 15 enum nmi_action { 16 NMI_SHOW_STATE = 1 << 0, 17 NMI_SHOW_REGS = 1 << 1, 18 NMI_DIE = 1 << 2, 19 NMI_DEBOUNCE = 1 << 3, 20 }; 21 22 static unsigned long nmi_actions; 23 24 static int nmi_debug_notify(struct notifier_block *self, 25 unsigned long val, void *data) 26 { 27 struct die_args *args = data; 28 29 if (likely(val != DIE_NMI)) 30 return NOTIFY_DONE; 31 32 if (nmi_actions & NMI_SHOW_STATE) 33 show_state(); 34 if (nmi_actions & NMI_SHOW_REGS) 35 show_regs(args->regs); 36 if (nmi_actions & NMI_DEBOUNCE) 37 mdelay(10); 38 if (nmi_actions & NMI_DIE) 39 return NOTIFY_BAD; 40 41 return NOTIFY_OK; 42 } 43 44 static struct notifier_block nmi_debug_nb = { 45 .notifier_call = nmi_debug_notify, 46 }; 47 48 static int __init nmi_debug_setup(char *str) 49 { 50 char *p, *sep; 51 52 register_die_notifier(&nmi_debug_nb); 53 54 if (*str != '=') 55 return 0; 56 57 for (p = str + 1; *p; p = sep + 1) { 58 sep = strchr(p, ','); 59 if (sep) 60 *sep = 0; 61 if (strcmp(p, "state") == 0) 62 nmi_actions |= NMI_SHOW_STATE; 63 else if (strcmp(p, "regs") == 0) 64 nmi_actions |= NMI_SHOW_REGS; 65 else if (strcmp(p, "debounce") == 0) 66 nmi_actions |= NMI_DEBOUNCE; 67 else if (strcmp(p, "die") == 0) 68 nmi_actions |= NMI_DIE; 69 else 70 printk(KERN_WARNING "NMI: Unrecognized action `%s'\n", 71 p); 72 if (!sep) 73 break; 74 } 75 76 return 0; 77 } 78 __setup("nmi_debug", nmi_debug_setup); 79