arch/blackfin/kernel/traps.c

   1 /*
   2  * File:         arch/blackfin/kernel/traps.c
   3  * Based on:
   4  * Author:       Hamish Macdonald
   5  *
   6  * Created:
   7  * Description:  uses S/W interrupt 15 for the system calls
   8  *
   9  * Modified:
  10  *               Copyright 2004-2006 Analog Devices Inc.
  11  *
  12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, see the file COPYING, or write
  26  * to the Free Software Foundation, Inc.,
  27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  28  */
  29
  30 #include <linux/uaccess.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/module.h>
  33 #include <linux/kallsyms.h>
  34 #include <linux/fs.h>
  35 #include <asm/traps.h>
  36 #include <asm/cacheflush.h>
  37 #include <asm/blackfin.h>
  38 #include <asm/irq_handler.h>
  39 #include <asm/trace.h>
  40 #include <asm/fixed_code.h>
  41
  42 #ifdef CONFIG_KGDB
  43 # include <linux/debugger.h>
  44 # include <linux/kgdb.h>
  45
  46 # define CHK_DEBUGGER_TRAP() \
  47         do { \
  48                 CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
  49         } while (0)
  50 # define CHK_DEBUGGER_TRAP_MAYBE() \
  51         do { \
  52                 if (kgdb_connected) \
  53                         CHK_DEBUGGER_TRAP(); \
  54         } while (0)
  55 #else
  56 # define CHK_DEBUGGER_TRAP() do { } while (0)
  57 # define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0)
  58 #endif
  59
  60 /* Initiate the event table handler */
  61 void __init trap_init(void)
  62 {
  63         CSYNC();
  64         bfin_write_EVT3(trap);
  65         CSYNC();
  66 }
  67
  68 int kstack_depth_to_print = 48;
  69
  70 static void decode_address(char *buf, unsigned long address)
  71 {
  72         struct vm_list_struct *vml;
  73         struct task_struct *p;
  74         struct mm_struct *mm;
  75         unsigned long flags, offset;
  76         unsigned int in_exception = bfin_read_IPEND() & 0x10;
  77
  78 #ifdef CONFIG_KALLSYMS
  79         unsigned long symsize;
  80         const char *symname;
  81         char *modname;
  82         char *delim = ":";
  83         char namebuf[128];
  84
  85         /* look up the address and see if we are in kernel space */
  86         symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);
  87
  88         if (symname) {
  89                 /* yeah! kernel space! */
  90                 if (!modname)
  91                         modname = delim = "";
  92                 sprintf(buf, "<0x%p> { %s%s%s%s + 0x%lx }",
  93                               (void *)address, delim, modname, delim, symname,
  94                               (unsigned long)offset);
  95                 return;
  96
  97         }
  98 #endif
  99
 100         /* Problem in fixed code section? */
 101         if (address >= FIXED_CODE_START && address < FIXED_CODE_END) {
 102                 sprintf(buf, "<0x%p> /* Maybe fixed code section */", (void *)address);
 103                 return;
 104         }
 105
 106         /* Problem somewhere before the kernel start address */
 107         if (address < CONFIG_BOOT_LOAD) {
 108                 sprintf(buf, "<0x%p> /* Maybe null pointer? */", (void *)address);
 109                 return;
 110         }
 111
 112         /* looks like we're off in user-land, so let's walk all the
 113          * mappings of all our processes and see if we can't be a whee
 114          * bit more specific
 115          */
 116         write_lock_irqsave(&tasklist_lock, flags);
 117         for_each_process(p) {
 118                 mm = (in_exception ? p->mm : get_task_mm(p));
 119                 if (!mm)
 120                         continue;
 121
 122                 vml = mm->context.vmlist;
 123                 while (vml) {
 124                         struct vm_area_struct *vma = vml->vma;
 125
 126                         if (address >= vma->vm_start && address < vma->vm_end) {
 127                                 char *name = p->comm;
 128                                 struct file *file = vma->vm_file;
 129                                 if (file) {
 130                                         char _tmpbuf[256];
 131                                         name = d_path(file->f_dentry,
 132                                                       file->f_vfsmnt,
 133                                                       _tmpbuf,
 134                                                       sizeof(_tmpbuf));
 135                                 }
 136
 137                                 /* FLAT does not have its text aligned to the start of
 138                                  * the map while FDPIC ELF does ...
 139                                  */
 140                                 if (current->mm &&
 141                                     (address > current->mm->start_code) &&
 142                                     (address < current->mm->end_code))
 143                                         offset = address - current->mm->start_code;
 144                                 else
 145                                         offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
 146
 147                                 sprintf(buf, "<0x%p> [ %s + 0x%lx ]",
 148                                         (void *)address, name, offset);
 149                                 if (!in_exception)
 150                                         mmput(mm);
 151                                 goto done;
 152                         }
 153
 154                         vml = vml->next;
 155                 }
 156                 if (!in_exception)
 157                         mmput(mm);
 158         }
 159
 160         /* we were unable to find this address anywhere */
 161         sprintf(buf, "<0x%p> /* unknown address */", (void *)address);
 162
 163 done:
 164         write_unlock_irqrestore(&tasklist_lock, flags);
 165 }
 166
 167 asmlinkage void double_fault_c(struct pt_regs *fp)
 168 {
 169         console_verbose();
 170         oops_in_progress = 1;
 171         printk(KERN_EMERG "\n" KERN_EMERG "Double Fault\n");
 172         dump_bfin_process(fp);
 173         dump_bfin_mem((void *)fp->retx);
 174         show_regs(fp);
 175         panic("Double Fault - unrecoverable event\n");
 176
 177 }
 178
 179 asmlinkage void trap_c(struct pt_regs *fp)
 180 {
 181 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
 182         int j;
 183 #endif
 184         int sig = 0;
 185         siginfo_t info;
 186         unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE;
 187
 188         trace_buffer_save(j);
 189
 190         /* Important - be very careful dereferncing pointers - will lead to
 191          * double faults if the stack has become corrupt
 192          */
 193
 194         /* If the fault was caused by a kernel thread, or interrupt handler
 195          * we will kernel panic, so the system reboots.
 196          * If KGDB is enabled, don't set this for kernel breakpoints
 197         */
 198         if ((bfin_read_IPEND() & 0xFFC0)
 199 #ifdef CONFIG_KGDB
 200                 && trapnr != VEC_EXCPT02
 201 #endif
 202         ){
 203                 console_verbose();
 204                 oops_in_progress = 1;
 205         } else if (current) {
 206                 if (current->mm == NULL) {
 207                         console_verbose();
 208                         oops_in_progress = 1;
 209                 }
 210         }
 211
 212         /* trap_c() will be called for exceptions. During exceptions
 213          * processing, the pc value should be set with retx value.
 214          * With this change we can cleanup some code in signal.c- TODO
 215          */
 216         fp->orig_pc = fp->retx;
 217         /* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n",
 218                 trapnr, fp->ipend, fp->pc, fp->retx); */
 219
 220         /* send the appropriate signal to the user program */
 221         switch (trapnr) {
 222
 223         /* This table works in conjuction with the one in ./mach-common/entry.S
 224          * Some exceptions are handled there (in assembly, in exception space)
 225          * Some are handled here, (in C, in interrupt space)
 226          * Some, like CPLB, are handled in both, where the normal path is
 227          * handled in assembly/exception space, and the error path is handled
 228          * here
 229          */
 230
 231         /* 0x00 - Linux Syscall, getting here is an error */
 232         /* 0x01 - userspace gdb breakpoint, handled here */
 233         case VEC_EXCPT01:
 234                 info.si_code = TRAP_ILLTRAP;
 235                 sig = SIGTRAP;
 236                 CHK_DEBUGGER_TRAP_MAYBE();
 237                 /* Check if this is a breakpoint in kernel space */
 238                 if (fp->ipend & 0xffc0)
 239                         return;
 240                 else
 241                         break;
 242 #ifdef CONFIG_KGDB
 243         case VEC_EXCPT02 :               /* gdb connection */
 244                 info.si_code = TRAP_ILLTRAP;
 245                 sig = SIGTRAP;
 246                 CHK_DEBUGGER_TRAP();
 247                 return;
 248 #else
 249         /* 0x02 - User Defined, Caught by default */
 250 #endif
 251         /* 0x03 - User Defined, userspace stack overflow */
 252         case VEC_EXCPT03:
 253                 info.si_code = SEGV_STACKFLOW;
 254                 sig = SIGSEGV;
 255                 printk(KERN_NOTICE EXC_0x03(KERN_NOTICE));
 256                 CHK_DEBUGGER_TRAP();
 257                 break;
 258         /* 0x04 - User Defined, Caught by default */
 259         /* 0x05 - User Defined, Caught by default */
 260         /* 0x06 - User Defined, Caught by default */
 261         /* 0x07 - User Defined, Caught by default */
 262         /* 0x08 - User Defined, Caught by default */
 263         /* 0x09 - User Defined, Caught by default */
 264         /* 0x0A - User Defined, Caught by default */
 265         /* 0x0B - User Defined, Caught by default */
 266         /* 0x0C - User Defined, Caught by default */
 267         /* 0x0D - User Defined, Caught by default */
 268         /* 0x0E - User Defined, Caught by default */
 269         /* 0x0F - User Defined, Caught by default */
 270         /* 0x10 HW Single step, handled here */
 271         case VEC_STEP:
 272                 info.si_code = TRAP_STEP;
 273                 sig = SIGTRAP;
 274                 CHK_DEBUGGER_TRAP_MAYBE();
 275                 /* Check if this is a single step in kernel space */
 276                 if (fp->ipend & 0xffc0)
 277                         return;
 278                 else
 279                         break;
 280         /* 0x11 - Trace Buffer Full, handled here */
 281         case VEC_OVFLOW:
 282                 info.si_code = TRAP_TRACEFLOW;
 283                 sig = SIGTRAP;
 284                 printk(KERN_NOTICE EXC_0x11(KERN_NOTICE));
 285                 CHK_DEBUGGER_TRAP();
 286                 break;
 287         /* 0x12 - Reserved, Caught by default */
 288         /* 0x13 - Reserved, Caught by default */
 289         /* 0x14 - Reserved, Caught by default */
 290         /* 0x15 - Reserved, Caught by default */
 291         /* 0x16 - Reserved, Caught by default */
 292         /* 0x17 - Reserved, Caught by default */
 293         /* 0x18 - Reserved, Caught by default */
 294         /* 0x19 - Reserved, Caught by default */
 295         /* 0x1A - Reserved, Caught by default */
 296         /* 0x1B - Reserved, Caught by default */
 297         /* 0x1C - Reserved, Caught by default */
 298         /* 0x1D - Reserved, Caught by default */
 299         /* 0x1E - Reserved, Caught by default */
 300         /* 0x1F - Reserved, Caught by default */
 301         /* 0x20 - Reserved, Caught by default */
 302         /* 0x21 - Undefined Instruction, handled here */
 303         case VEC_UNDEF_I:
 304                 info.si_code = ILL_ILLOPC;
 305                 sig = SIGILL;
 306                 printk(KERN_NOTICE EXC_0x21(KERN_NOTICE));
 307                 CHK_DEBUGGER_TRAP();
 308                 break;
 309         /* 0x22 - Illegal Instruction Combination, handled here */
 310         case VEC_ILGAL_I:
 311                 info.si_code = ILL_ILLPARAOP;
 312                 sig = SIGILL;
 313                 printk(KERN_NOTICE EXC_0x22(KERN_NOTICE));
 314                 CHK_DEBUGGER_TRAP();
 315                 break;
 316         /* 0x23 - Data CPLB protection violation, handled here */
 317         case VEC_CPLB_VL:
 318                 info.si_code = ILL_CPLB_VI;
 319                 sig = SIGBUS;
 320                 printk(KERN_NOTICE EXC_0x23(KERN_NOTICE));
 321                 CHK_DEBUGGER_TRAP();
 322                 break;
 323         /* 0x24 - Data access misaligned, handled here */
 324         case VEC_MISALI_D:
 325                 info.si_code = BUS_ADRALN;
 326                 sig = SIGBUS;
 327                 printk(KERN_NOTICE EXC_0x24(KERN_NOTICE));
 328                 CHK_DEBUGGER_TRAP();
 329                 break;
 330         /* 0x25 - Unrecoverable Event, handled here */
 331         case VEC_UNCOV:
 332                 info.si_code = ILL_ILLEXCPT;
 333                 sig = SIGILL;
 334                 printk(KERN_NOTICE EXC_0x25(KERN_NOTICE));
 335                 CHK_DEBUGGER_TRAP();
 336                 break;
 337         /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
 338                 error case is handled here */
 339         case VEC_CPLB_M:
 340                 info.si_code = BUS_ADRALN;
 341                 sig = SIGBUS;
 342                 printk(KERN_NOTICE EXC_0x26(KERN_NOTICE));
 343                 CHK_DEBUGGER_TRAP();
 344                 break;
 345         /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
 346         case VEC_CPLB_MHIT:
 347                 info.si_code = ILL_CPLB_MULHIT;
 348 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
 349                 sig = SIGSEGV;
 350                 printk(KERN_NOTICE "NULL pointer access (probably)\n");
 351 #else
 352                 sig = SIGILL;
 353                 printk(KERN_NOTICE EXC_0x27(KERN_NOTICE));
 354 #endif
 355                 CHK_DEBUGGER_TRAP();
 356                 break;
 357         /* 0x28 - Emulation Watchpoint, handled here */
 358         case VEC_WATCH:
 359                 info.si_code = TRAP_WATCHPT;
 360                 sig = SIGTRAP;
 361                 pr_debug(EXC_0x28(KERN_DEBUG));
 362                 CHK_DEBUGGER_TRAP_MAYBE();
 363                 /* Check if this is a watchpoint in kernel space */
 364                 if (fp->ipend & 0xffc0)
 365                         return;
 366                 else
 367                         break;
 368 #ifdef CONFIG_BF535
 369         /* 0x29 - Instruction fetch access error (535 only) */
 370         case VEC_ISTRU_VL:      /* ADSP-BF535 only (MH) */
 371                 info.si_code = BUS_OPFETCH;
 372                 sig = SIGBUS;
 373                 printk(KERN_NOTICE "BF535: VEC_ISTRU_VL\n");
 374                 CHK_DEBUGGER_TRAP();
 375                 break;
 376 #else
 377         /* 0x29 - Reserved, Caught by default */
 378 #endif
 379         /* 0x2A - Instruction fetch misaligned, handled here */
 380         case VEC_MISALI_I:
 381                 info.si_code = BUS_ADRALN;
 382                 sig = SIGBUS;
 383                 printk(KERN_NOTICE EXC_0x2A(KERN_NOTICE));
 384                 CHK_DEBUGGER_TRAP();
 385                 break;
 386         /* 0x2B - Instruction CPLB protection violation, handled here */
 387         case VEC_CPLB_I_VL:
 388                 info.si_code = ILL_CPLB_VI;
 389                 sig = SIGBUS;
 390                 printk(KERN_NOTICE EXC_0x2B(KERN_NOTICE));
 391                 CHK_DEBUGGER_TRAP();
 392                 break;
 393         /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
 394         case VEC_CPLB_I_M:
 395                 info.si_code = ILL_CPLB_MISS;
 396                 sig = SIGBUS;
 397                 printk(KERN_NOTICE EXC_0x2C(KERN_NOTICE));
 398                 CHK_DEBUGGER_TRAP();
 399                 break;
 400         /* 0x2D - Instruction CPLB Multiple Hits, handled here */
 401         case VEC_CPLB_I_MHIT:
 402                 info.si_code = ILL_CPLB_MULHIT;
 403 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
 404                 sig = SIGSEGV;
 405                 printk(KERN_NOTICE "Jump to address 0 - 0x0fff\n");
 406 #else
 407                 sig = SIGILL;
 408                 printk(KERN_NOTICE EXC_0x2D(KERN_NOTICE));
 409 #endif
 410                 CHK_DEBUGGER_TRAP();
 411                 break;
 412         /* 0x2E - Illegal use of Supervisor Resource, handled here */
 413         case VEC_ILL_RES:
 414                 info.si_code = ILL_PRVOPC;
 415                 sig = SIGILL;
 416                 printk(KERN_NOTICE EXC_0x2E(KERN_NOTICE));
 417                 CHK_DEBUGGER_TRAP();
 418                 break;
 419         /* 0x2F - Reserved, Caught by default */
 420         /* 0x30 - Reserved, Caught by default */
 421         /* 0x31 - Reserved, Caught by default */
 422         /* 0x32 - Reserved, Caught by default */
 423         /* 0x33 - Reserved, Caught by default */
 424         /* 0x34 - Reserved, Caught by default */
 425         /* 0x35 - Reserved, Caught by default */
 426         /* 0x36 - Reserved, Caught by default */
 427         /* 0x37 - Reserved, Caught by default */
 428         /* 0x38 - Reserved, Caught by default */
 429         /* 0x39 - Reserved, Caught by default */
 430         /* 0x3A - Reserved, Caught by default */
 431         /* 0x3B - Reserved, Caught by default */
 432         /* 0x3C - Reserved, Caught by default */
 433         /* 0x3D - Reserved, Caught by default */
 434         /* 0x3E - Reserved, Caught by default */
 435         /* 0x3F - Reserved, Caught by default */
 436         default:
 437                 info.si_code = TRAP_ILLTRAP;
 438                 sig = SIGTRAP;
 439                 printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n",
 440                         (fp->seqstat & SEQSTAT_EXCAUSE));
 441                 CHK_DEBUGGER_TRAP();
 442                 break;
 443         }
 444
 445         BUG_ON(sig == 0);
 446
 447         if (sig != SIGTRAP) {
 448                 unsigned long stack;
 449                 dump_bfin_process(fp);
 450                 dump_bfin_mem((void *)fp->retx);
 451                 show_regs(fp);
 452
 453                 /* Print out the trace buffer if it makes sense */
 454 #ifndef CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE
 455                 if (trapnr == VEC_CPLB_I_M || trapnr == VEC_CPLB_M)
 456                         printk(KERN_NOTICE "No trace since you do not have "
 457                                 "CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE enabled\n"
 458                                 KERN_NOTICE "\n");
 459                 else
 460 #endif
 461                         dump_bfin_trace_buffer();
 462                 show_stack(current, &stack);
 463                 if (oops_in_progress) {
 464 #ifndef CONFIG_ACCESS_CHECK
 465                         printk(KERN_EMERG "Please turn on "
 466                                "CONFIG_ACCESS_CHECK\n");
 467 #endif
 468                         panic("Kernel exception");
 469                 }
 470         }
 471
 472         info.si_signo = sig;
 473         info.si_errno = 0;
 474         info.si_addr = (void *)fp->pc;
 475         force_sig_info(sig, &info, current);
 476
 477         /* Ensure that bad return addresses don't end up in an infinite
 478          * loop, due to speculative loads/reads. This needs to be done after
 479          * the signal has been sent.
 480          */
 481         if (trapnr == VEC_CPLB_I_M && sig != SIGTRAP)
 482                 fp->pc = SAFE_USER_INSTRUCTION;
 483
 484         trace_buffer_restore(j);
 485         return;
 486 }
 487
 488 /* Typical exception handling routines  */
 489
 490 #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)
 491
 492 void dump_bfin_trace_buffer(void)
 493 {
 494 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
 495         int tflags, i = 0;
 496         char buf[150];
 497 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
 498         int j, index;
 499 #endif
 500
 501         trace_buffer_save(tflags);
 502
 503         printk(KERN_NOTICE "Hardware Trace:\n");
 504
 505         if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) {
 506                 for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
 507                         decode_address(buf, (unsigned long)bfin_read_TBUF());
 508                         printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
 509                         decode_address(buf, (unsigned long)bfin_read_TBUF());
 510                         printk(KERN_NOTICE "     Source : %s\n", buf);
 511                 }
 512         }
 513
 514 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
 515         if (trace_buff_offset)
 516                 index = trace_buff_offset/4 - 1;
 517         else
 518                 index = EXPAND_LEN;
 519
 520         j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128;
 521         while (j) {
 522                 decode_address(buf, software_trace_buff[index]);
 523                 printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
 524                 index -= 1;
 525                 if (index < 0 )
 526                         index = EXPAND_LEN;
 527                 decode_address(buf, software_trace_buff[index]);
 528                 printk(KERN_NOTICE "     Source : %s\n", buf);
 529                 index -= 1;
 530                 if (index < 0)
 531                         index = EXPAND_LEN;
 532                 j--;
 533                 i++;
 534         }
 535 #endif
 536
 537         trace_buffer_restore(tflags);
 538 #endif
 539 }
 540 EXPORT_SYMBOL(dump_bfin_trace_buffer);
 541
 542 static void show_trace(struct task_struct *tsk, unsigned long *sp)
 543 {
 544         unsigned long addr;
 545
 546         printk(KERN_NOTICE "\n" KERN_NOTICE "Call Trace:\n");
 547
 548         while (!kstack_end(sp)) {
 549                 addr = *sp++;
 550                 /*
 551                  * If the address is either in the text segment of the
 552                  * kernel, or in the region which contains vmalloc'ed
 553                  * memory, it *may* be the address of a calling
 554                  * routine; if so, print it so that someone tracing
 555                  * down the cause of the crash will be able to figure
 556                  * out the call path that was taken.
 557                  */
 558                 if (kernel_text_address(addr))
 559                         print_ip_sym(addr);
 560         }
 561
 562         printk(KERN_NOTICE "\n");
 563 }
 564
 565 void show_stack(struct task_struct *task, unsigned long *stack)
 566 {
 567         unsigned long *endstack, addr;
 568         int i;
 569
 570         /* Cannot call dump_bfin_trace_buffer() here as show_stack() is
 571          * called externally in some places in the kernel.
 572          */
 573
 574         if (!stack) {
 575                 if (task)
 576                         stack = (unsigned long *)task->thread.ksp;
 577                 else
 578                         stack = (unsigned long *)&stack;
 579         }
 580
 581         addr = (unsigned long)stack;
 582         endstack = (unsigned long *)PAGE_ALIGN(addr);
 583
 584         printk(KERN_NOTICE "Stack from %08lx:", (unsigned long)stack);
 585         for (i = 0; i < kstack_depth_to_print; i++) {
 586                 if (stack + 1 > endstack)
 587                         break;
 588                 if (i % 8 == 0)
 589                         printk("\n" KERN_NOTICE "       ");
 590                 printk(" %08lx", *stack++);
 591         }
 592         printk("\n");
 593
 594         show_trace(task, stack);
 595 }
 596
 597 void dump_stack(void)
 598 {
 599         unsigned long stack;
 600 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
 601         int tflags;
 602 #endif
 603         trace_buffer_save(tflags);
 604         dump_bfin_trace_buffer();
 605         show_stack(current, &stack);
 606         trace_buffer_restore(tflags);
 607 }
 608 EXPORT_SYMBOL(dump_stack);
 609
 610 void dump_bfin_process(struct pt_regs *fp)
 611 {
 612         /* We should be able to look at fp->ipend, but we don't push it on the
 613          * stack all the time, so do this until we fix that */
 614         unsigned int context = bfin_read_IPEND();
 615
 616         if (oops_in_progress)
 617                 printk(KERN_EMERG "Kernel OOPS in progress\n");
 618
 619         if (context & 0x0020)
 620                 printk(KERN_NOTICE "Deferred excecption or HW Error context\n");
 621         else if (context & 0x3FC0)
 622                 printk(KERN_NOTICE "Interrupt context\n");
 623         else if (context & 0x4000)
 624                 printk(KERN_NOTICE "Deferred Interrupt context\n");
 625         else if (context & 0x8000)
 626                 printk(KERN_NOTICE "Kernel process context\n");
 627
 628         if (current->pid && current->mm) {
 629                 printk(KERN_NOTICE "CURRENT PROCESS:\n");
 630                 printk(KERN_NOTICE "COMM=%s PID=%d\n",
 631                         current->comm, current->pid);
 632
 633                 printk(KERN_NOTICE "TEXT = 0x%p-0x%p  DATA = 0x%p-0x%p\n"
 634                         KERN_NOTICE "BSS = 0x%p-0x%p   USER-STACK = 0x%p\n"
 635                         KERN_NOTICE "\n",
 636                         (void *)current->mm->start_code,
 637                         (void *)current->mm->end_code,
 638                         (void *)current->mm->start_data,
 639                         (void *)current->mm->end_data,
 640                         (void *)current->mm->end_data,
 641                         (void *)current->mm->brk,
 642                         (void *)current->mm->start_stack);
 643         } else
 644                 printk(KERN_NOTICE "\n" KERN_NOTICE
 645                      "No Valid process in current context\n");
 646 }
 647
 648 void dump_bfin_mem(void *retaddr)
 649 {
 650
 651         if (retaddr >= (void *)FIXED_CODE_START  && retaddr < (void *)physical_mem_end
 652 #if L1_CODE_LENGTH != 0
 653             /* FIXME: Copy the code out of L1 Instruction SRAM through dma
 654                memcpy.  */
 655             && !(retaddr >= (void *)L1_CODE_START
 656                  && retaddr < (void *)(L1_CODE_START + L1_CODE_LENGTH))
 657 #endif
 658         ) {
 659                 int i = ((unsigned int)retaddr & 0xFFFFFFF0) - 32;
 660                 unsigned short x = 0;
 661                 printk(KERN_NOTICE "return address: [0x%p]; contents of:", retaddr);
 662                 for (; i < ((unsigned int)retaddr & 0xFFFFFFF0) + 32; i += 2) {
 663                         if (!(i & 0xF))
 664                                 printk("\n" KERN_NOTICE "0x%08x: ", i);
 665
 666                         if (get_user(x, (unsigned short *)i))
 667                                 break;
 668 #ifndef CONFIG_DEBUG_HWERR
 669                         /* If one of the last few instructions was a STI
 670                          * it is likely that the error occured awhile ago
 671                          * and we just noticed. This only happens in kernel
 672                          * context, which should mean an oops is happening
 673                          */
 674                         if (oops_in_progress && x >= 0x0040 && x <= 0x0047 && i <= 0)
 675                                 panic("\n\nWARNING : You should reconfigure"
 676                                         " the kernel to turn on\n"
 677                                         " 'Hardware error interrupt"
 678                                         " debugging'\n"
 679                                         " The rest of this error"
 680                                         " is meanless\n");
 681 #endif
 682                         if (i == (unsigned int)retaddr)
 683                                 printk("[%04x]", x);
 684                         else
 685                                 printk(" %04x ", x);
 686                 }
 687                 printk("\n");
 688         } else
 689                 printk("\n" KERN_NOTICE
 690                         "Cannot look at the [PC] <%p> for it is"
 691                         " in unreadable memory - sorry\n", retaddr);
 692 }
 693
 694 void show_regs(struct pt_regs *fp)
 695 {
 696         char buf [150];
 697
 698         printk(KERN_NOTICE "\n" KERN_NOTICE "SEQUENCER STATUS:\n");
 699         printk(KERN_NOTICE " SEQSTAT: %08lx  IPEND: %04lx  SYSCFG: %04lx\n",
 700                 (long)fp->seqstat, fp->ipend, fp->syscfg);
 701
 702         decode_address(buf, fp->rete);
 703         printk(KERN_NOTICE " RETE: %s\n", buf);
 704         decode_address(buf, fp->retn);
 705         printk(KERN_NOTICE " RETN: %s\n", buf);
 706         decode_address(buf, fp->retx);
 707         printk(KERN_NOTICE " RETX: %s\n", buf);
 708         decode_address(buf, fp->rets);
 709         printk(KERN_NOTICE " RETS: %s\n", buf);
 710         decode_address(buf, fp->pc);
 711         printk(KERN_NOTICE " PC: %s\n", buf);
 712
 713         if ((long)fp->seqstat & SEQSTAT_EXCAUSE) {
 714                 decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
 715                 printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
 716                 decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
 717                 printk(KERN_NOTICE "ICPLB_FAULT_ADDR: %s\n", buf);
 718         }
 719
 720         printk(KERN_NOTICE "\n" KERN_NOTICE "PROCESSOR STATE:\n");
 721         printk(KERN_NOTICE " R0 : %08lx    R1 : %08lx    R2 : %08lx    R3 : %08lx\n",
 722                 fp->r0, fp->r1, fp->r2, fp->r3);
 723         printk(KERN_NOTICE " R4 : %08lx    R5 : %08lx    R6 : %08lx    R7 : %08lx\n",
 724                 fp->r4, fp->r5, fp->r6, fp->r7);
 725         printk(KERN_NOTICE " P0 : %08lx    P1 : %08lx    P2 : %08lx    P3 : %08lx\n",
 726                 fp->p0, fp->p1, fp->p2, fp->p3);
 727         printk(KERN_NOTICE " P4 : %08lx    P5 : %08lx    FP : %08lx    SP : %08lx\n",
 728                 fp->p4, fp->p5, fp->fp, (long)fp);
 729         printk(KERN_NOTICE " LB0: %08lx    LT0: %08lx    LC0: %08lx\n",
 730                 fp->lb0, fp->lt0, fp->lc0);
 731         printk(KERN_NOTICE " LB1: %08lx    LT1: %08lx    LC1: %08lx\n",
 732                 fp->lb1, fp->lt1, fp->lc1);
 733         printk(KERN_NOTICE " B0 : %08lx    L0 : %08lx    M0 : %08lx    I0 : %08lx\n",
 734                 fp->b0, fp->l0, fp->m0, fp->i0);
 735         printk(KERN_NOTICE " B1 : %08lx    L1 : %08lx    M1 : %08lx    I1 : %08lx\n",
 736                 fp->b1, fp->l1, fp->m1, fp->i1);
 737         printk(KERN_NOTICE " B2 : %08lx    L2 : %08lx    M2 : %08lx    I2 : %08lx\n",
 738                 fp->b2, fp->l2, fp->m2, fp->i2);
 739         printk(KERN_NOTICE " B3 : %08lx    L3 : %08lx    M3 : %08lx    I3 : %08lx\n",
 740                 fp->b3, fp->l3, fp->m3, fp->i3);
 741         printk(KERN_NOTICE "A0.w: %08lx   A0.x: %08lx   A1.w: %08lx   A1.x: %08lx\n",
 742                 fp->a0w, fp->a0x, fp->a1w, fp->a1x);
 743
 744         printk(KERN_NOTICE "USP : %08lx  ASTAT: %08lx\n",
 745                 rdusp(), fp->astat);
 746
 747         printk(KERN_NOTICE "\n");
 748 }
 749
 750 #ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
 751 asmlinkage int sys_bfin_spinlock(int *spinlock)__attribute__((l1_text));
 752 #endif
 753
 754 asmlinkage int sys_bfin_spinlock(int *spinlock)
 755 {
 756         int ret = 0;
 757         int tmp = 0;
 758
 759         local_irq_disable();
 760         ret = get_user(tmp, spinlock);
 761         if (ret == 0) {
 762                 if (tmp)
 763                         ret = 1;
 764                 tmp = 1;
 765                 put_user(tmp, spinlock);
 766         }
 767         local_irq_enable();
 768         return ret;
 769 }
 770
 771 int bfin_request_exception(unsigned int exception, void (*handler)(void))
 772 {
 773         void (*curr_handler)(void);
 774
 775         if (exception > 0x3F)
 776                 return -EINVAL;
 777
 778         curr_handler = ex_table[exception];
 779
 780         if (curr_handler != ex_replaceable)
 781                 return -EBUSY;
 782
 783         ex_table[exception] = handler;
 784
 785         return 0;
 786 }
 787 EXPORT_SYMBOL(bfin_request_exception);
 788
 789 int bfin_free_exception(unsigned int exception, void (*handler)(void))
 790 {
 791         void (*curr_handler)(void);
 792
 793         if (exception > 0x3F)
 794                 return -EINVAL;
 795
 796         curr_handler = ex_table[exception];
 797
 798         if (curr_handler != handler)
 799                 return -EBUSY;
 800
 801         ex_table[exception] = ex_replaceable;
 802
 803         return 0;
 804 }
 805 EXPORT_SYMBOL(bfin_free_exception);
 806
 807 void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
 808 {
 809         switch (cplb_panic) {
 810         case CPLB_NO_UNLOCKED:
 811                 printk(KERN_EMERG "All CPLBs are locked\n");
 812                 break;
 813         case CPLB_PROT_VIOL:
 814                 return;
 815         case CPLB_NO_ADDR_MATCH:
 816                 return;
 817         case CPLB_UNKNOWN_ERR:
 818                 printk(KERN_EMERG "Unknown CPLB Exception\n");
 819                 break;
 820         }
 821
 822         oops_in_progress = 1;
 823
 824         printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
 825         printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
 826         dump_bfin_process(fp);
 827         dump_bfin_mem((void *)fp->retx);
 828         show_regs(fp);
 829         dump_stack();
 830         panic("Unrecoverable event\n");
 831 }