1 /* 2 * HW exception handling 3 * 4 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu> 5 * Copyright (C) 2008 PetaLogix 6 * 7 * This file is subject to the terms and conditions of the GNU General 8 * Public License. See the file COPYING in the main directory of this 9 * archive for more details. 10 */ 11 12 /* 13 * This file handles the architecture-dependent parts of hardware exceptions 14 */ 15 16 #include <linux/kernel.h> 17 #include <linux/signal.h> 18 #include <linux/sched.h> 19 #include <linux/kallsyms.h> 20 #include <linux/module.h> 21 22 #include <asm/exceptions.h> 23 #include <asm/entry.h> /* For KM CPU var */ 24 #include <linux/uaccess.h> 25 #include <linux/errno.h> 26 #include <linux/ptrace.h> 27 #include <asm/current.h> 28 29 #define MICROBLAZE_ILL_OPCODE_EXCEPTION 0x02 30 #define MICROBLAZE_IBUS_EXCEPTION 0x03 31 #define MICROBLAZE_DBUS_EXCEPTION 0x04 32 #define MICROBLAZE_DIV_ZERO_EXCEPTION 0x05 33 #define MICROBLAZE_FPU_EXCEPTION 0x06 34 #define MICROBLAZE_PRIVILEGED_EXCEPTION 0x07 35 36 static DEFINE_SPINLOCK(die_lock); 37 38 void die(const char *str, struct pt_regs *fp, long err) 39 { 40 console_verbose(); 41 spin_lock_irq(&die_lock); 42 printk(KERN_WARNING "Oops: %s, sig: %ld\n", str, err); 43 show_regs(fp); 44 spin_unlock_irq(&die_lock); 45 /* do_exit() should take care of panic'ing from an interrupt 46 * context so we don't handle it here 47 */ 48 do_exit(err); 49 } 50 51 /* for user application debugging */ 52 void sw_exception(struct pt_regs *regs) 53 { 54 _exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16); 55 } 56 57 void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) 58 { 59 siginfo_t info; 60 61 if (kernel_mode(regs)) { 62 die("Exception in kernel mode", regs, signr); 63 } 64 info.si_signo = signr; 65 info.si_errno = 0; 66 info.si_code = code; 67 info.si_addr = (void __user *) addr; 68 force_sig_info(signr, &info, current); 69 } 70 71 asmlinkage void full_exception(struct pt_regs *regs, unsigned int type, 72 int fsr, int addr) 73 { 74 #ifdef CONFIG_MMU 75 addr = regs->pc; 76 #endif 77 78 #if 0 79 printk(KERN_WARNING "Exception %02x in %s mode, FSR=%08x PC=%08x " \ 80 "ESR=%08x\n", 81 type, user_mode(regs) ? "user" : "kernel", fsr, 82 (unsigned int) regs->pc, (unsigned int) regs->esr); 83 #endif 84 85 switch (type & 0x1F) { 86 case MICROBLAZE_ILL_OPCODE_EXCEPTION: 87 if (user_mode(regs)) { 88 pr_debug("Illegal opcode exception in user mode\n"); 89 _exception(SIGILL, regs, ILL_ILLOPC, addr); 90 return; 91 } 92 printk(KERN_WARNING "Illegal opcode exception " \ 93 "in kernel mode.\n"); 94 die("opcode exception", regs, SIGBUS); 95 break; 96 case MICROBLAZE_IBUS_EXCEPTION: 97 if (user_mode(regs)) { 98 pr_debug("Instruction bus error exception in user mode\n"); 99 _exception(SIGBUS, regs, BUS_ADRERR, addr); 100 return; 101 } 102 printk(KERN_WARNING "Instruction bus error exception " \ 103 "in kernel mode.\n"); 104 die("bus exception", regs, SIGBUS); 105 break; 106 case MICROBLAZE_DBUS_EXCEPTION: 107 if (user_mode(regs)) { 108 pr_debug("Data bus error exception in user mode\n"); 109 _exception(SIGBUS, regs, BUS_ADRERR, addr); 110 return; 111 } 112 printk(KERN_WARNING "Data bus error exception " \ 113 "in kernel mode.\n"); 114 die("bus exception", regs, SIGBUS); 115 break; 116 case MICROBLAZE_DIV_ZERO_EXCEPTION: 117 if (user_mode(regs)) { 118 pr_debug("Divide by zero exception in user mode\n"); 119 _exception(SIGILL, regs, FPE_INTDIV, addr); 120 return; 121 } 122 printk(KERN_WARNING "Divide by zero exception " \ 123 "in kernel mode.\n"); 124 die("Divide by zero exception", regs, SIGBUS); 125 break; 126 case MICROBLAZE_FPU_EXCEPTION: 127 pr_debug("FPU exception\n"); 128 /* IEEE FP exception */ 129 /* I removed fsr variable and use code var for storing fsr */ 130 if (fsr & FSR_IO) 131 fsr = FPE_FLTINV; 132 else if (fsr & FSR_OF) 133 fsr = FPE_FLTOVF; 134 else if (fsr & FSR_UF) 135 fsr = FPE_FLTUND; 136 else if (fsr & FSR_DZ) 137 fsr = FPE_FLTDIV; 138 else if (fsr & FSR_DO) 139 fsr = FPE_FLTRES; 140 _exception(SIGFPE, regs, fsr, addr); 141 break; 142 143 #ifdef CONFIG_MMU 144 case MICROBLAZE_PRIVILEGED_EXCEPTION: 145 pr_debug("Privileged exception\n"); 146 _exception(SIGILL, regs, ILL_PRVOPC, addr); 147 break; 148 #endif 149 default: 150 /* FIXME what to do in unexpected exception */ 151 printk(KERN_WARNING "Unexpected exception %02x " 152 "PC=%08x in %s mode\n", type, (unsigned int) addr, 153 kernel_mode(regs) ? "kernel" : "user"); 154 } 155 return; 156 } 157