arch/c6x/kernel/traps.c

   1 /*
   2  *  Port on Texas Instruments TMS320C6x architecture
   3  *
   4  *  Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated
   5  *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  */
  11 #include <linux/module.h>
  12 #include <linux/ptrace.h>
  13 #include <linux/kallsyms.h>
  14 #include <linux/bug.h>
  15
  16 #include <asm/soc.h>
  17 #include <asm/special_insns.h>
  18 #include <asm/traps.h>
  19
  20 int (*c6x_nmi_handler)(struct pt_regs *regs);
  21
  22 void __init trap_init(void)
  23 {
  24         ack_exception(EXCEPT_TYPE_NXF);
  25         ack_exception(EXCEPT_TYPE_EXC);
  26         ack_exception(EXCEPT_TYPE_IXF);
  27         ack_exception(EXCEPT_TYPE_SXF);
  28         enable_exception();
  29 }
  30
  31 void show_regs(struct pt_regs *regs)
  32 {
  33         pr_err("\n");
  34         pr_err("PC: %08lx SP: %08lx\n", regs->pc, regs->sp);
  35         pr_err("Status: %08lx ORIG_A4: %08lx\n", regs->csr, regs->orig_a4);
  36         pr_err("A0: %08lx  B0: %08lx\n", regs->a0, regs->b0);
  37         pr_err("A1: %08lx  B1: %08lx\n", regs->a1, regs->b1);
  38         pr_err("A2: %08lx  B2: %08lx\n", regs->a2, regs->b2);
  39         pr_err("A3: %08lx  B3: %08lx\n", regs->a3, regs->b3);
  40         pr_err("A4: %08lx  B4: %08lx\n", regs->a4, regs->b4);
  41         pr_err("A5: %08lx  B5: %08lx\n", regs->a5, regs->b5);
  42         pr_err("A6: %08lx  B6: %08lx\n", regs->a6, regs->b6);
  43         pr_err("A7: %08lx  B7: %08lx\n", regs->a7, regs->b7);
  44         pr_err("A8: %08lx  B8: %08lx\n", regs->a8, regs->b8);
  45         pr_err("A9: %08lx  B9: %08lx\n", regs->a9, regs->b9);
  46         pr_err("A10: %08lx  B10: %08lx\n", regs->a10, regs->b10);
  47         pr_err("A11: %08lx  B11: %08lx\n", regs->a11, regs->b11);
  48         pr_err("A12: %08lx  B12: %08lx\n", regs->a12, regs->b12);
  49         pr_err("A13: %08lx  B13: %08lx\n", regs->a13, regs->b13);
  50         pr_err("A14: %08lx  B14: %08lx\n", regs->a14, regs->dp);
  51         pr_err("A15: %08lx  B15: %08lx\n", regs->a15, regs->sp);
  52         pr_err("A16: %08lx  B16: %08lx\n", regs->a16, regs->b16);
  53         pr_err("A17: %08lx  B17: %08lx\n", regs->a17, regs->b17);
  54         pr_err("A18: %08lx  B18: %08lx\n", regs->a18, regs->b18);
  55         pr_err("A19: %08lx  B19: %08lx\n", regs->a19, regs->b19);
  56         pr_err("A20: %08lx  B20: %08lx\n", regs->a20, regs->b20);
  57         pr_err("A21: %08lx  B21: %08lx\n", regs->a21, regs->b21);
  58         pr_err("A22: %08lx  B22: %08lx\n", regs->a22, regs->b22);
  59         pr_err("A23: %08lx  B23: %08lx\n", regs->a23, regs->b23);
  60         pr_err("A24: %08lx  B24: %08lx\n", regs->a24, regs->b24);
  61         pr_err("A25: %08lx  B25: %08lx\n", regs->a25, regs->b25);
  62         pr_err("A26: %08lx  B26: %08lx\n", regs->a26, regs->b26);
  63         pr_err("A27: %08lx  B27: %08lx\n", regs->a27, regs->b27);
  64         pr_err("A28: %08lx  B28: %08lx\n", regs->a28, regs->b28);
  65         pr_err("A29: %08lx  B29: %08lx\n", regs->a29, regs->b29);
  66         pr_err("A30: %08lx  B30: %08lx\n", regs->a30, regs->b30);
  67         pr_err("A31: %08lx  B31: %08lx\n", regs->a31, regs->b31);
  68 }
  69
  70 void dump_stack(void)
  71 {
  72         unsigned long stack;
  73
  74         show_stack(current, &stack);
  75 }
  76 EXPORT_SYMBOL(dump_stack);
  77
  78
  79 void die(char *str, struct pt_regs *fp, int nr)
  80 {
  81         console_verbose();
  82         pr_err("%s: %08x\n", str, nr);
  83         show_regs(fp);
  84
  85         pr_err("Process %s (pid: %d, stackpage=%08lx)\n",
  86                current->comm, current->pid, (PAGE_SIZE +
  87                                              (unsigned long) current));
  88
  89         dump_stack();
  90         while (1)
  91                 ;
  92 }
  93
  94 static void die_if_kernel(char *str, struct pt_regs *fp, int nr)
  95 {
  96         if (user_mode(fp))
  97                 return;
  98
  99         die(str, fp, nr);
 100 }
 101
 102
 103 /* Internal exceptions */
 104 static struct exception_info iexcept_table[10] = {
 105         { "Oops - instruction fetch", SIGBUS, BUS_ADRERR },
 106         { "Oops - fetch packet", SIGBUS, BUS_ADRERR },
 107         { "Oops - execute packet", SIGILL, ILL_ILLOPC },
 108         { "Oops - undefined instruction", SIGILL, ILL_ILLOPC },
 109         { "Oops - resource conflict", SIGILL, ILL_ILLOPC },
 110         { "Oops - resource access", SIGILL, ILL_PRVREG },
 111         { "Oops - privilege", SIGILL, ILL_PRVOPC },
 112         { "Oops - loops buffer", SIGILL, ILL_ILLOPC },
 113         { "Oops - software exception", SIGILL, ILL_ILLTRP },
 114         { "Oops - unknown exception", SIGILL, ILL_ILLOPC }
 115 };
 116
 117 /* External exceptions */
 118 static struct exception_info eexcept_table[128] = {
 119         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 120         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 121         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 122         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 123         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 124         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 125         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 126         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 127         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 128         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 129         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 130         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 131         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 132         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 133         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 134         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 135         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 136         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 137         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 138         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 139         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 140         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 141         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 142         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 143         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 144         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 145         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 146         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 147         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 148         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 149         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 150         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 151
 152         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 153         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 154         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 155         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 156         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 157         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 158         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 159         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 160         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 161         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 162         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 163         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 164         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 165         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 166         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 167         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 168         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 169         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 170         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 171         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 172         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 173         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 174         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 175         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 176         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 177         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 178         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 179         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 180         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 181         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 182         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 183         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 184
 185         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 186         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 187         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 188         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 189         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 190         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 191         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 192         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 193         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 194         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 195         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 196         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 197         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 198         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 199         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 200         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 201         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 202         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 203         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 204         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 205         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 206         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 207         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 208         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 209         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 210         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 211         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 212         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 213         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 214         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 215         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 216         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 217
 218         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 219         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 220         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 221         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 222         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 223         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 224         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 225         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 226         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 227         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 228         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 229         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 230         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 231         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 232         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 233         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 234         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 235         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 236         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 237         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 238         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 239         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 240         { "Oops - external exception", SIGBUS, BUS_ADRERR },
 241         { "Oops - CPU memory protection fault", SIGSEGV, SEGV_ACCERR },
 242         { "Oops - CPU memory protection fault in L1P", SIGSEGV, SEGV_ACCERR },
 243         { "Oops - DMA memory protection fault in L1P", SIGSEGV, SEGV_ACCERR },
 244         { "Oops - CPU memory protection fault in L1D", SIGSEGV, SEGV_ACCERR },
 245         { "Oops - DMA memory protection fault in L1D", SIGSEGV, SEGV_ACCERR },
 246         { "Oops - CPU memory protection fault in L2", SIGSEGV, SEGV_ACCERR },
 247         { "Oops - DMA memory protection fault in L2", SIGSEGV, SEGV_ACCERR },
 248         { "Oops - EMC CPU memory protection fault", SIGSEGV, SEGV_ACCERR },
 249         { "Oops - EMC bus error", SIGBUS, BUS_ADRERR }
 250 };
 251
 252 static void do_trap(struct exception_info *except_info, struct pt_regs *regs)
 253 {
 254         unsigned long addr = instruction_pointer(regs);
 255         siginfo_t info;
 256
 257         if (except_info->code != TRAP_BRKPT)
 258                 pr_err("TRAP: %s PC[0x%lx] signo[%d] code[%d]\n",
 259                        except_info->kernel_str, regs->pc,
 260                        except_info->signo, except_info->code);
 261
 262         die_if_kernel(except_info->kernel_str, regs, addr);
 263
 264         info.si_signo = except_info->signo;
 265         info.si_errno = 0;
 266         info.si_code  = except_info->code;
 267         info.si_addr  = (void __user *)addr;
 268
 269         force_sig_info(except_info->signo, &info, current);
 270 }
 271
 272 /*
 273  * Process an internal exception (non maskable)
 274  */
 275 static int process_iexcept(struct pt_regs *regs)
 276 {
 277         unsigned int iexcept_report = get_iexcept();
 278         unsigned int iexcept_num;
 279
 280         ack_exception(EXCEPT_TYPE_IXF);
 281
 282         pr_err("IEXCEPT: PC[0x%lx]\n", regs->pc);
 283
 284         while (iexcept_report) {
 285                 iexcept_num = __ffs(iexcept_report);
 286                 iexcept_report &= ~(1 << iexcept_num);
 287                 set_iexcept(iexcept_report);
 288                 if (*(unsigned int *)regs->pc == BKPT_OPCODE) {
 289                         /* This is a breakpoint */
 290                         struct exception_info bkpt_exception = {
 291                                 "Oops - undefined instruction",
 292                                   SIGTRAP, TRAP_BRKPT
 293                         };
 294                         do_trap(&bkpt_exception, regs);
 295                         iexcept_report &= ~(0xFF);
 296                         set_iexcept(iexcept_report);
 297                         continue;
 298                 }
 299
 300                 do_trap(&iexcept_table[iexcept_num], regs);
 301         }
 302         return 0;
 303 }
 304
 305 /*
 306  * Process an external exception (maskable)
 307  */
 308 static void process_eexcept(struct pt_regs *regs)
 309 {
 310         int evt;
 311
 312         pr_err("EEXCEPT: PC[0x%lx]\n", regs->pc);
 313
 314         while ((evt = soc_get_exception()) >= 0)
 315                 do_trap(&eexcept_table[evt], regs);
 316
 317         ack_exception(EXCEPT_TYPE_EXC);
 318 }
 319
 320 /*
 321  * Main exception processing
 322  */
 323 asmlinkage int process_exception(struct pt_regs *regs)
 324 {
 325         unsigned int type;
 326         unsigned int type_num;
 327         unsigned int ie_num = 9; /* default is unknown exception */
 328
 329         while ((type = get_except_type()) != 0) {
 330                 type_num = fls(type) - 1;
 331
 332                 switch (type_num) {
 333                 case EXCEPT_TYPE_NXF:
 334                         ack_exception(EXCEPT_TYPE_NXF);
 335                         if (c6x_nmi_handler)
 336                                 (c6x_nmi_handler)(regs);
 337                         else
 338                                 pr_alert("NMI interrupt!\n");
 339                         break;
 340
 341                 case EXCEPT_TYPE_IXF:
 342                         if (process_iexcept(regs))
 343                                 return 1;
 344                         break;
 345
 346                 case EXCEPT_TYPE_EXC:
 347                         process_eexcept(regs);
 348                         break;
 349
 350                 case EXCEPT_TYPE_SXF:
 351                         ie_num = 8;
 352                 default:
 353                         ack_exception(type_num);
 354                         do_trap(&iexcept_table[ie_num], regs);
 355                         break;
 356                 }
 357         }
 358         return 0;
 359 }
 360
 361 static int kstack_depth_to_print = 48;
 362
 363 static void show_trace(unsigned long *stack, unsigned long *endstack)
 364 {
 365         unsigned long addr;
 366         int i;
 367
 368         pr_debug("Call trace:");
 369         i = 0;
 370         while (stack + 1 <= endstack) {
 371                 addr = *stack++;
 372                 /*
 373                  * If the address is either in the text segment of the
 374                  * kernel, or in the region which contains vmalloc'ed
 375                  * memory, it *may* be the address of a calling
 376                  * routine; if so, print it so that someone tracing
 377                  * down the cause of the crash will be able to figure
 378                  * out the call path that was taken.
 379                  */
 380                 if (__kernel_text_address(addr)) {
 381 #ifndef CONFIG_KALLSYMS
 382                         if (i % 5 == 0)
 383                                 pr_debug("\n        ");
 384 #endif
 385                         pr_debug(" [<%08lx>]", addr);
 386                         print_symbol(" %s\n", addr);
 387                         i++;
 388                 }
 389         }
 390         pr_debug("\n");
 391 }
 392
 393 void show_stack(struct task_struct *task, unsigned long *stack)
 394 {
 395         unsigned long *p, *endstack;
 396         int i;
 397
 398         if (!stack) {
 399                 if (task && task != current)
 400                         /* We know this is a kernel stack,
 401                            so this is the start/end */
 402                         stack = (unsigned long *)thread_saved_ksp(task);
 403                 else
 404                         stack = (unsigned long *)&stack;
 405         }
 406         endstack = (unsigned long *)(((unsigned long)stack + THREAD_SIZE - 1)
 407                                      & -THREAD_SIZE);
 408
 409         pr_debug("Stack from %08lx:", (unsigned long)stack);
 410         for (i = 0, p = stack; i < kstack_depth_to_print; i++) {
 411                 if (p + 1 > endstack)
 412                         break;
 413                 if (i % 8 == 0)
 414                         pr_cont("\n         ");
 415                 pr_cont(" %08lx", *p++);
 416         }
 417         pr_cont("\n");
 418         show_trace(stack, endstack);
 419 }
 420
 421 int is_valid_bugaddr(unsigned long addr)
 422 {
 423         return __kernel_text_address(addr);
 424 }