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/export.h> |
17 | #include <linux/kernel.h> |
18 | #include <linux/signal.h> |
19 | #include <linux/sched.h> |
20 | #include <linux/sched/debug.h> |
21 | #include <linux/kallsyms.h> |
22 | |
23 | #include <asm/exceptions.h> |
24 | #include <asm/entry.h> /* For KM CPU var */ |
25 | #include <linux/uaccess.h> |
26 | #include <linux/errno.h> |
27 | #include <linux/ptrace.h> |
28 | #include <asm/current.h> |
29 | #include <asm/cacheflush.h> |
30 | |
31 | #define MICROBLAZE_ILL_OPCODE_EXCEPTION 0x02 |
32 | #define MICROBLAZE_IBUS_EXCEPTION 0x03 |
33 | #define MICROBLAZE_DBUS_EXCEPTION 0x04 |
34 | #define MICROBLAZE_DIV_ZERO_EXCEPTION 0x05 |
35 | #define MICROBLAZE_FPU_EXCEPTION 0x06 |
36 | #define MICROBLAZE_PRIVILEGED_EXCEPTION 0x07 |
37 | |
38 | static DEFINE_SPINLOCK(die_lock); |
39 | |
40 | void die(const char *str, struct pt_regs *fp, long err) |
41 | { |
42 | console_verbose(); |
43 | spin_lock_irq(lock: &die_lock); |
44 | pr_warn("Oops: %s, sig: %ld\n" , str, err); |
45 | show_regs(fp); |
46 | spin_unlock_irq(lock: &die_lock); |
47 | /* make_task_dead() should take care of panic'ing from an interrupt |
48 | * context so we don't handle it here |
49 | */ |
50 | make_task_dead(signr: err); |
51 | } |
52 | |
53 | /* for user application debugging */ |
54 | asmlinkage void sw_exception(struct pt_regs *regs) |
55 | { |
56 | _exception(SIGTRAP, regs, TRAP_BRKPT, regs->r16); |
57 | flush_dcache_range(regs->r16, regs->r16 + 0x4); |
58 | flush_icache_range(regs->start: r16, regs->end: r16 + 0x4); |
59 | } |
60 | |
61 | void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr) |
62 | { |
63 | if (kernel_mode(regs)) |
64 | die(str: "Exception in kernel mode" , fp: regs, err: signr); |
65 | |
66 | force_sig_fault(sig: signr, code, addr: (void __user *)addr); |
67 | } |
68 | |
69 | asmlinkage void full_exception(struct pt_regs *regs, unsigned int type, |
70 | int fsr, int addr) |
71 | { |
72 | addr = regs->pc; |
73 | |
74 | #if 0 |
75 | pr_warn("Exception %02x in %s mode, FSR=%08x PC=%08x ESR=%08x\n" , |
76 | type, user_mode(regs) ? "user" : "kernel" , fsr, |
77 | (unsigned int) regs->pc, (unsigned int) regs->esr); |
78 | #endif |
79 | |
80 | switch (type & 0x1F) { |
81 | case MICROBLAZE_ILL_OPCODE_EXCEPTION: |
82 | if (user_mode(regs)) { |
83 | pr_debug("Illegal opcode exception in user mode\n" ); |
84 | _exception(SIGILL, regs, ILL_ILLOPC, addr); |
85 | return; |
86 | } |
87 | pr_warn("Illegal opcode exception in kernel mode.\n" ); |
88 | die(str: "opcode exception" , fp: regs, SIGBUS); |
89 | break; |
90 | case MICROBLAZE_IBUS_EXCEPTION: |
91 | if (user_mode(regs)) { |
92 | pr_debug("Instruction bus error exception in user mode\n" ); |
93 | _exception(SIGBUS, regs, BUS_ADRERR, addr); |
94 | return; |
95 | } |
96 | pr_warn("Instruction bus error exception in kernel mode.\n" ); |
97 | die(str: "bus exception" , fp: regs, SIGBUS); |
98 | break; |
99 | case MICROBLAZE_DBUS_EXCEPTION: |
100 | if (user_mode(regs)) { |
101 | pr_debug("Data bus error exception in user mode\n" ); |
102 | _exception(SIGBUS, regs, BUS_ADRERR, addr); |
103 | return; |
104 | } |
105 | pr_warn("Data bus error exception in kernel mode.\n" ); |
106 | die(str: "bus exception" , fp: regs, SIGBUS); |
107 | break; |
108 | case MICROBLAZE_DIV_ZERO_EXCEPTION: |
109 | if (user_mode(regs)) { |
110 | pr_debug("Divide by zero exception in user mode\n" ); |
111 | _exception(SIGFPE, regs, FPE_INTDIV, addr); |
112 | return; |
113 | } |
114 | pr_warn("Divide by zero exception in kernel mode.\n" ); |
115 | die(str: "Divide by zero exception" , fp: regs, SIGBUS); |
116 | break; |
117 | case MICROBLAZE_FPU_EXCEPTION: |
118 | pr_debug("FPU exception\n" ); |
119 | /* IEEE FP exception */ |
120 | /* I removed fsr variable and use code var for storing fsr */ |
121 | if (fsr & FSR_IO) |
122 | fsr = FPE_FLTINV; |
123 | else if (fsr & FSR_OF) |
124 | fsr = FPE_FLTOVF; |
125 | else if (fsr & FSR_UF) |
126 | fsr = FPE_FLTUND; |
127 | else if (fsr & FSR_DZ) |
128 | fsr = FPE_FLTDIV; |
129 | else if (fsr & FSR_DO) |
130 | fsr = FPE_FLTRES; |
131 | _exception(SIGFPE, regs, fsr, addr); |
132 | break; |
133 | case MICROBLAZE_PRIVILEGED_EXCEPTION: |
134 | pr_debug("Privileged exception\n" ); |
135 | _exception(SIGILL, regs, ILL_PRVOPC, addr); |
136 | break; |
137 | default: |
138 | /* FIXME what to do in unexpected exception */ |
139 | pr_warn("Unexpected exception %02x PC=%08x in %s mode\n" , |
140 | type, (unsigned int) addr, |
141 | kernel_mode(regs) ? "kernel" : "user" ); |
142 | } |
143 | return; |
144 | } |
145 | |