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   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * arch/sh64/kernel/traps.c
   7  *
   8  * Copyright (C) 2000, 2001  Paolo Alberelli
   9  * Copyright (C) 2003, 2004  Paul Mundt
  10  * Copyright (C) 2003, 2004  Richard Curnow
  11  *
  12  */
  13
  14 /*
  15  * 'Traps.c' handles hardware traps and faults after we have saved some
  16  * state in 'entry.S'.
  17  */
  18 #include <linux/sched.h>
  19 #include <linux/kernel.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/ptrace.h>
  23 #include <linux/timer.h>
  24 #include <linux/mm.h>
  25 #include <linux/smp.h>
  26 #include <linux/init.h>
  27 #include <linux/delay.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/kallsyms.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/sysctl.h>
  32 #include <linux/module.h>
  33 #include <asm/system.h>
  34 #include <asm/uaccess.h>
  35 #include <asm/io.h>
  36 #include <asm/atomic.h>
  37 #include <asm/processor.h>
  38 #include <asm/pgtable.h>
  39
  40 #undef DEBUG_EXCEPTION
  41 #ifdef DEBUG_EXCEPTION
  42 /* implemented in ../lib/dbg.c */
  43 extern void show_excp_regs(char *fname, int trapnr, int signr,
  44                            struct pt_regs *regs);
  45 #else
  46 #define show_excp_regs(a, b, c, d)
  47 #endif
  48
  49 static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
  50                 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk);
  51
  52 #define DO_ERROR(trapnr, signr, str, name, tsk) \
  53 asmlinkage void do_##name(unsigned long error_code, struct pt_regs *regs) \
  54 { \
  55         do_unhandled_exception(trapnr, signr, str, __stringify(name), error_code, regs, current); \
  56 }
  57
  58 spinlock_t die_lock;
  59
  60 void die(const char * str, struct pt_regs * regs, long err)
  61 {
  62         console_verbose();
  63         spin_lock_irq(&die_lock);
  64         printk("%s: %lx\n", str, (err & 0xffffff));
  65         show_regs(regs);
  66         spin_unlock_irq(&die_lock);
  67         do_exit(SIGSEGV);
  68 }
  69
  70 static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
  71 {
  72         if (!user_mode(regs))
  73                 die(str, regs, err);
  74 }
  75
  76 static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
  77 {
  78         if (!user_mode(regs)) {
  79                 const struct exception_table_entry *fixup;
  80                 fixup = search_exception_tables(regs->pc);
  81                 if (fixup) {
  82                         regs->pc = fixup->fixup;
  83                         return;
  84                 }
  85                 die(str, regs, err);
  86         }
  87 }
  88
  89 DO_ERROR(13, SIGILL,  "illegal slot instruction", illegal_slot_inst, current)
  90 DO_ERROR(87, SIGSEGV, "address error (exec)", address_error_exec, current)
  91
  92
  93 /* Implement misaligned load/store handling for kernel (and optionally for user
  94    mode too).  Limitation : only SHmedia mode code is handled - there is no
  95    handling at all for misaligned accesses occurring in SHcompact code yet. */
  96
  97 static int misaligned_fixup(struct pt_regs *regs);
  98
  99 asmlinkage void do_address_error_load(unsigned long error_code, struct pt_regs *regs)
 100 {
 101         if (misaligned_fixup(regs) < 0) {
 102                 do_unhandled_exception(7, SIGSEGV, "address error(load)",
 103                                 "do_address_error_load",
 104                                 error_code, regs, current);
 105         }
 106         return;
 107 }
 108
 109 asmlinkage void do_address_error_store(unsigned long error_code, struct pt_regs *regs)
 110 {
 111         if (misaligned_fixup(regs) < 0) {
 112                 do_unhandled_exception(8, SIGSEGV, "address error(store)",
 113                                 "do_address_error_store",
 114                                 error_code, regs, current);
 115         }
 116         return;
 117 }
 118
 119 #if defined(CONFIG_SH64_ID2815_WORKAROUND)
 120
 121 #define OPCODE_INVALID      0
 122 #define OPCODE_USER_VALID   1
 123 #define OPCODE_PRIV_VALID   2
 124
 125 /* getcon/putcon - requires checking which control register is referenced. */
 126 #define OPCODE_CTRL_REG     3
 127
 128 /* Table of valid opcodes for SHmedia mode.
 129    Form a 10-bit value by concatenating the major/minor opcodes i.e.
 130    opcode[31:26,20:16].  The 6 MSBs of this value index into the following
 131    array.  The 4 LSBs select the bit-pair in the entry (bits 1:0 correspond to
 132    LSBs==4'b0000 etc). */
 133 static unsigned long shmedia_opcode_table[64] = {
 134         0x55554044,0x54445055,0x15141514,0x14541414,0x00000000,0x10001000,0x01110055,0x04050015,
 135         0x00000444,0xc0000000,0x44545515,0x40405555,0x55550015,0x10005555,0x55555505,0x04050000,
 136         0x00000555,0x00000404,0x00040445,0x15151414,0x00000000,0x00000000,0x00000000,0x00000000,
 137         0x00000055,0x40404444,0x00000404,0xc0009495,0x00000000,0x00000000,0x00000000,0x00000000,
 138         0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
 139         0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
 140         0x80005050,0x04005055,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
 141         0x81055554,0x00000404,0x55555555,0x55555555,0x00000000,0x00000000,0x00000000,0x00000000
 142 };
 143
 144 void do_reserved_inst(unsigned long error_code, struct pt_regs *regs)
 145 {
 146         /* Workaround SH5-101 cut2 silicon defect #2815 :
 147            in some situations, inter-mode branches from SHcompact -> SHmedia
 148            which should take ITLBMISS or EXECPROT exceptions at the target
 149            falsely take RESINST at the target instead. */
 150
 151         unsigned long opcode = 0x6ff4fff0; /* guaranteed reserved opcode */
 152         unsigned long pc, aligned_pc;
 153         int get_user_error;
 154         int trapnr = 12;
 155         int signr = SIGILL;
 156         char *exception_name = "reserved_instruction";
 157
 158         pc = regs->pc;
 159         if ((pc & 3) == 1) {
 160                 /* SHmedia : check for defect.  This requires executable vmas
 161                    to be readable too. */
 162                 aligned_pc = pc & ~3;
 163                 if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
 164                         get_user_error = -EFAULT;
 165                 } else {
 166                         get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
 167                 }
 168                 if (get_user_error >= 0) {
 169                         unsigned long index, shift;
 170                         unsigned long major, minor, combined;
 171                         unsigned long reserved_field;
 172                         reserved_field = opcode & 0xf; /* These bits are currently reserved as zero in all valid opcodes */
 173                         major = (opcode >> 26) & 0x3f;
 174                         minor = (opcode >> 16) & 0xf;
 175                         combined = (major << 4) | minor;
 176                         index = major;
 177                         shift = minor << 1;
 178                         if (reserved_field == 0) {
 179                                 int opcode_state = (shmedia_opcode_table[index] >> shift) & 0x3;
 180                                 switch (opcode_state) {
 181                                         case OPCODE_INVALID:
 182                                                 /* Trap. */
 183                                                 break;
 184                                         case OPCODE_USER_VALID:
 185                                                 /* Restart the instruction : the branch to the instruction will now be from an RTE
 186                                                    not from SHcompact so the silicon defect won't be triggered. */
 187                                                 return;
 188                                         case OPCODE_PRIV_VALID:
 189                                                 if (!user_mode(regs)) {
 190                                                         /* Should only ever get here if a module has
 191                                                            SHcompact code inside it.  If so, the same fix up is needed. */
 192                                                         return; /* same reason */
 193                                                 }
 194                                                 /* Otherwise, user mode trying to execute a privileged instruction -
 195                                                    fall through to trap. */
 196                                                 break;
 197                                         case OPCODE_CTRL_REG:
 198                                                 /* If in privileged mode, return as above. */
 199                                                 if (!user_mode(regs)) return;
 200                                                 /* In user mode ... */
 201                                                 if (combined == 0x9f) { /* GETCON */
 202                                                         unsigned long regno = (opcode >> 20) & 0x3f;
 203                                                         if (regno >= 62) {
 204                                                                 return;
 205                                                         }
 206                                                         /* Otherwise, reserved or privileged control register, => trap */
 207                                                 } else if (combined == 0x1bf) { /* PUTCON */
 208                                                         unsigned long regno = (opcode >> 4) & 0x3f;
 209                                                         if (regno >= 62) {
 210                                                                 return;
 211                                                         }
 212                                                         /* Otherwise, reserved or privileged control register, => trap */
 213                                                 } else {
 214                                                         /* Trap */
 215                                                 }
 216                                                 break;
 217                                         default:
 218                                                 /* Fall through to trap. */
 219                                                 break;
 220                                 }
 221                         }
 222                         /* fall through to normal resinst processing */
 223                 } else {
 224                         /* Error trying to read opcode.  This typically means a
 225                            real fault, not a RESINST any more.  So change the
 226                            codes. */
 227                         trapnr = 87;
 228                         exception_name = "address error (exec)";
 229                         signr = SIGSEGV;
 230                 }
 231         }
 232
 233         do_unhandled_exception(trapnr, signr, exception_name, "do_reserved_inst", error_code, regs, current);
 234 }
 235
 236 #else /* CONFIG_SH64_ID2815_WORKAROUND */
 237
 238 /* If the workaround isn't needed, this is just a straightforward reserved
 239    instruction */
 240 DO_ERROR(12, SIGILL,  "reserved instruction", reserved_inst, current)
 241
 242 #endif /* CONFIG_SH64_ID2815_WORKAROUND */
 243
 244 /* Called with interrupts disabled */
 245 asmlinkage void do_exception_error(unsigned long ex, struct pt_regs *regs)
 246 {
 247         show_excp_regs(__FUNCTION__, -1, -1, regs);
 248         die_if_kernel("exception", regs, ex);
 249 }
 250
 251 int do_unknown_trapa(unsigned long scId, struct pt_regs *regs)
 252 {
 253         /* Syscall debug */
 254         printk("System call ID error: [0x1#args:8 #syscall:16  0x%lx]\n", scId);
 255
 256         die_if_kernel("unknown trapa", regs, scId);
 257
 258         return -ENOSYS;
 259 }
 260
 261 void show_stack(struct task_struct *tsk, unsigned long *sp)
 262 {
 263 #ifdef CONFIG_KALLSYMS
 264         extern void sh64_unwind(struct pt_regs *regs);
 265         struct pt_regs *regs;
 266
 267         regs = tsk ? tsk->thread.kregs : NULL;
 268
 269         sh64_unwind(regs);
 270 #else
 271         printk(KERN_ERR "Can't backtrace on sh64 without CONFIG_KALLSYMS\n");
 272 #endif
 273 }
 274
 275 void show_task(unsigned long *sp)
 276 {
 277         show_stack(NULL, sp);
 278 }
 279
 280 void dump_stack(void)
 281 {
 282         show_task(NULL);
 283 }
 284 /* Needed by any user of WARN_ON in view of the defn in include/asm-sh/bug.h */
 285 EXPORT_SYMBOL(dump_stack);
 286
 287 static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
 288                 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk)
 289 {
 290         show_excp_regs(fn_name, trapnr, signr, regs);
 291         tsk->thread.error_code = error_code;
 292         tsk->thread.trap_no = trapnr;
 293
 294         if (user_mode(regs))
 295                 force_sig(signr, tsk);
 296
 297         die_if_no_fixup(str, regs, error_code);
 298 }
 299
 300 static int read_opcode(unsigned long long pc, unsigned long *result_opcode, int from_user_mode)
 301 {
 302         int get_user_error;
 303         unsigned long aligned_pc;
 304         unsigned long opcode;
 305
 306         if ((pc & 3) == 1) {
 307                 /* SHmedia */
 308                 aligned_pc = pc & ~3;
 309                 if (from_user_mode) {
 310                         if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
 311                                 get_user_error = -EFAULT;
 312                         } else {
 313                                 get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
 314                                 *result_opcode = opcode;
 315                         }
 316                         return get_user_error;
 317                 } else {
 318                         /* If the fault was in the kernel, we can either read
 319                          * this directly, or if not, we fault.
 320                         */
 321                         *result_opcode = *(unsigned long *) aligned_pc;
 322                         return 0;
 323                 }
 324         } else if ((pc & 1) == 0) {
 325                 /* SHcompact */
 326                 /* TODO : provide handling for this.  We don't really support
 327                    user-mode SHcompact yet, and for a kernel fault, this would
 328                    have to come from a module built for SHcompact.  */
 329                 return -EFAULT;
 330         } else {
 331                 /* misaligned */
 332                 return -EFAULT;
 333         }
 334 }
 335
 336 static int address_is_sign_extended(__u64 a)
 337 {
 338         __u64 b;
 339 #if (NEFF == 32)
 340         b = (__u64)(__s64)(__s32)(a & 0xffffffffUL);
 341         return (b == a) ? 1 : 0;
 342 #else
 343 #error "Sign extend check only works for NEFF==32"
 344 #endif
 345 }
 346
 347 static int generate_and_check_address(struct pt_regs *regs,
 348                                       __u32 opcode,
 349                                       int displacement_not_indexed,
 350                                       int width_shift,
 351                                       __u64 *address)
 352 {
 353         /* return -1 for fault, 0 for OK */
 354
 355         __u64 base_address, addr;
 356         int basereg;
 357
 358         basereg = (opcode >> 20) & 0x3f;
 359         base_address = regs->regs[basereg];
 360         if (displacement_not_indexed) {
 361                 __s64 displacement;
 362                 displacement = (opcode >> 10) & 0x3ff;
 363                 displacement = ((displacement << 54) >> 54); /* sign extend */
 364                 addr = (__u64)((__s64)base_address + (displacement << width_shift));
 365         } else {
 366                 __u64 offset;
 367                 int offsetreg;
 368                 offsetreg = (opcode >> 10) & 0x3f;
 369                 offset = regs->regs[offsetreg];
 370                 addr = base_address + offset;
 371         }
 372
 373         /* Check sign extended */
 374         if (!address_is_sign_extended(addr)) {
 375                 return -1;
 376         }
 377
 378 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 379         /* Check accessible.  For misaligned access in the kernel, assume the
 380            address is always accessible (and if not, just fault when the
 381            load/store gets done.) */
 382         if (user_mode(regs)) {
 383                 if (addr >= TASK_SIZE) {
 384                         return -1;
 385                 }
 386                 /* Do access_ok check later - it depends on whether it's a load or a store. */
 387         }
 388 #endif
 389
 390         *address = addr;
 391         return 0;
 392 }
 393
 394 /* Default value as for sh */
 395 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 396 static int user_mode_unaligned_fixup_count = 10;
 397 static int user_mode_unaligned_fixup_enable = 1;
 398 #endif
 399
 400 static int kernel_mode_unaligned_fixup_count = 32;
 401
 402 static void misaligned_kernel_word_load(__u64 address, int do_sign_extend, __u64 *result)
 403 {
 404         unsigned short x;
 405         unsigned char *p, *q;
 406         p = (unsigned char *) (int) address;
 407         q = (unsigned char *) &x;
 408         q[0] = p[0];
 409         q[1] = p[1];
 410
 411         if (do_sign_extend) {
 412                 *result = (__u64)(__s64) *(short *) &x;
 413         } else {
 414                 *result = (__u64) x;
 415         }
 416 }
 417
 418 static void misaligned_kernel_word_store(__u64 address, __u64 value)
 419 {
 420         unsigned short x;
 421         unsigned char *p, *q;
 422         p = (unsigned char *) (int) address;
 423         q = (unsigned char *) &x;
 424
 425         x = (__u16) value;
 426         p[0] = q[0];
 427         p[1] = q[1];
 428 }
 429
 430 static int misaligned_load(struct pt_regs *regs,
 431                            __u32 opcode,
 432                            int displacement_not_indexed,
 433                            int width_shift,
 434                            int do_sign_extend)
 435 {
 436         /* Return -1 for a fault, 0 for OK */
 437         int error;
 438         int destreg;
 439         __u64 address;
 440
 441         error = generate_and_check_address(regs, opcode,
 442                         displacement_not_indexed, width_shift, &address);
 443         if (error < 0) {
 444                 return error;
 445         }
 446
 447         destreg = (opcode >> 4) & 0x3f;
 448 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 449         if (user_mode(regs)) {
 450                 __u64 buffer;
 451
 452                 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
 453                         return -1;
 454                 }
 455
 456                 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
 457                         return -1; /* fault */
 458                 }
 459                 switch (width_shift) {
 460                 case 1:
 461                         if (do_sign_extend) {
 462                                 regs->regs[destreg] = (__u64)(__s64) *(__s16 *) &buffer;
 463                         } else {
 464                                 regs->regs[destreg] = (__u64) *(__u16 *) &buffer;
 465                         }
 466                         break;
 467                 case 2:
 468                         regs->regs[destreg] = (__u64)(__s64) *(__s32 *) &buffer;
 469                         break;
 470                 case 3:
 471                         regs->regs[destreg] = buffer;
 472                         break;
 473                 default:
 474                         printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
 475                                 width_shift, (unsigned long) regs->pc);
 476                         break;
 477                 }
 478         } else
 479 #endif
 480         {
 481                 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
 482                 __u64 lo, hi;
 483
 484                 switch (width_shift) {
 485                 case 1:
 486                         misaligned_kernel_word_load(address, do_sign_extend, &regs->regs[destreg]);
 487                         break;
 488                 case 2:
 489                         asm ("ldlo.l %1, 0, %0" : "=r" (lo) : "r" (address));
 490                         asm ("ldhi.l %1, 3, %0" : "=r" (hi) : "r" (address));
 491                         regs->regs[destreg] = lo | hi;
 492                         break;
 493                 case 3:
 494                         asm ("ldlo.q %1, 0, %0" : "=r" (lo) : "r" (address));
 495                         asm ("ldhi.q %1, 7, %0" : "=r" (hi) : "r" (address));
 496                         regs->regs[destreg] = lo | hi;
 497                         break;
 498
 499                 default:
 500                         printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
 501                                 width_shift, (unsigned long) regs->pc);
 502                         break;
 503                 }
 504         }
 505
 506         return 0;
 507
 508 }
 509
 510 static int misaligned_store(struct pt_regs *regs,
 511                             __u32 opcode,
 512                             int displacement_not_indexed,
 513                             int width_shift)
 514 {
 515         /* Return -1 for a fault, 0 for OK */
 516         int error;
 517         int srcreg;
 518         __u64 address;
 519
 520         error = generate_and_check_address(regs, opcode,
 521                         displacement_not_indexed, width_shift, &address);
 522         if (error < 0) {
 523                 return error;
 524         }
 525
 526         srcreg = (opcode >> 4) & 0x3f;
 527 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 528         if (user_mode(regs)) {
 529                 __u64 buffer;
 530
 531                 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
 532                         return -1;
 533                 }
 534
 535                 switch (width_shift) {
 536                 case 1:
 537                         *(__u16 *) &buffer = (__u16) regs->regs[srcreg];
 538                         break;
 539                 case 2:
 540                         *(__u32 *) &buffer = (__u32) regs->regs[srcreg];
 541                         break;
 542                 case 3:
 543                         buffer = regs->regs[srcreg];
 544                         break;
 545                 default:
 546                         printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
 547                                 width_shift, (unsigned long) regs->pc);
 548                         break;
 549                 }
 550
 551                 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
 552                         return -1; /* fault */
 553                 }
 554         } else
 555 #endif
 556         {
 557                 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
 558                 __u64 val = regs->regs[srcreg];
 559
 560                 switch (width_shift) {
 561                 case 1:
 562                         misaligned_kernel_word_store(address, val);
 563                         break;
 564                 case 2:
 565                         asm ("stlo.l %1, 0, %0" : : "r" (val), "r" (address));
 566                         asm ("sthi.l %1, 3, %0" : : "r" (val), "r" (address));
 567                         break;
 568                 case 3:
 569                         asm ("stlo.q %1, 0, %0" : : "r" (val), "r" (address));
 570                         asm ("sthi.q %1, 7, %0" : : "r" (val), "r" (address));
 571                         break;
 572
 573                 default:
 574                         printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
 575                                 width_shift, (unsigned long) regs->pc);
 576                         break;
 577                 }
 578         }
 579
 580         return 0;
 581
 582 }
 583
 584 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 585 /* Never need to fix up misaligned FPU accesses within the kernel since that's a real
 586    error. */
 587 static int misaligned_fpu_load(struct pt_regs *regs,
 588                            __u32 opcode,
 589                            int displacement_not_indexed,
 590                            int width_shift,
 591                            int do_paired_load)
 592 {
 593         /* Return -1 for a fault, 0 for OK */
 594         int error;
 595         int destreg;
 596         __u64 address;
 597
 598         error = generate_and_check_address(regs, opcode,
 599                         displacement_not_indexed, width_shift, &address);
 600         if (error < 0) {
 601                 return error;
 602         }
 603
 604         destreg = (opcode >> 4) & 0x3f;
 605         if (user_mode(regs)) {
 606                 __u64 buffer;
 607                 __u32 buflo, bufhi;
 608
 609                 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
 610                         return -1;
 611                 }
 612
 613                 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
 614                         return -1; /* fault */
 615                 }
 616                 /* 'current' may be the current owner of the FPU state, so
 617                    context switch the registers into memory so they can be
 618                    indexed by register number. */
 619                 if (last_task_used_math == current) {
 620                         grab_fpu();
 621                         fpsave(&current->thread.fpu.hard);
 622                         release_fpu();
 623                         last_task_used_math = NULL;
 624                         regs->sr |= SR_FD;
 625                 }
 626
 627                 buflo = *(__u32*) &buffer;
 628                 bufhi = *(1 + (__u32*) &buffer);
 629
 630                 switch (width_shift) {
 631                 case 2:
 632                         current->thread.fpu.hard.fp_regs[destreg] = buflo;
 633                         break;
 634                 case 3:
 635                         if (do_paired_load) {
 636                                 current->thread.fpu.hard.fp_regs[destreg] = buflo;
 637                                 current->thread.fpu.hard.fp_regs[destreg+1] = bufhi;
 638                         } else {
 639 #if defined(CONFIG_LITTLE_ENDIAN)
 640                                 current->thread.fpu.hard.fp_regs[destreg] = bufhi;
 641                                 current->thread.fpu.hard.fp_regs[destreg+1] = buflo;
 642 #else
 643                                 current->thread.fpu.hard.fp_regs[destreg] = buflo;
 644                                 current->thread.fpu.hard.fp_regs[destreg+1] = bufhi;
 645 #endif
 646                         }
 647                         break;
 648                 default:
 649                         printk("Unexpected width_shift %d in misaligned_fpu_load, PC=%08lx\n",
 650                                 width_shift, (unsigned long) regs->pc);
 651                         break;
 652                 }
 653                 return 0;
 654         } else {
 655                 die ("Misaligned FPU load inside kernel", regs, 0);
 656                 return -1;
 657         }
 658
 659
 660 }
 661
 662 static int misaligned_fpu_store(struct pt_regs *regs,
 663                            __u32 opcode,
 664                            int displacement_not_indexed,
 665                            int width_shift,
 666                            int do_paired_load)
 667 {
 668         /* Return -1 for a fault, 0 for OK */
 669         int error;
 670         int srcreg;
 671         __u64 address;
 672
 673         error = generate_and_check_address(regs, opcode,
 674                         displacement_not_indexed, width_shift, &address);
 675         if (error < 0) {
 676                 return error;
 677         }
 678
 679         srcreg = (opcode >> 4) & 0x3f;
 680         if (user_mode(regs)) {
 681                 __u64 buffer;
 682                 /* Initialise these to NaNs. */
 683                 __u32 buflo=0xffffffffUL, bufhi=0xffffffffUL;
 684
 685                 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
 686                         return -1;
 687                 }
 688
 689                 /* 'current' may be the current owner of the FPU state, so
 690                    context switch the registers into memory so they can be
 691                    indexed by register number. */
 692                 if (last_task_used_math == current) {
 693                         grab_fpu();
 694                         fpsave(&current->thread.fpu.hard);
 695                         release_fpu();
 696                         last_task_used_math = NULL;
 697                         regs->sr |= SR_FD;
 698                 }
 699
 700                 switch (width_shift) {
 701                 case 2:
 702                         buflo = current->thread.fpu.hard.fp_regs[srcreg];
 703                         break;
 704                 case 3:
 705                         if (do_paired_load) {
 706                                 buflo = current->thread.fpu.hard.fp_regs[srcreg];
 707                                 bufhi = current->thread.fpu.hard.fp_regs[srcreg+1];
 708                         } else {
 709 #if defined(CONFIG_LITTLE_ENDIAN)
 710                                 bufhi = current->thread.fpu.hard.fp_regs[srcreg];
 711                                 buflo = current->thread.fpu.hard.fp_regs[srcreg+1];
 712 #else
 713                                 buflo = current->thread.fpu.hard.fp_regs[srcreg];
 714                                 bufhi = current->thread.fpu.hard.fp_regs[srcreg+1];
 715 #endif
 716                         }
 717                         break;
 718                 default:
 719                         printk("Unexpected width_shift %d in misaligned_fpu_store, PC=%08lx\n",
 720                                 width_shift, (unsigned long) regs->pc);
 721                         break;
 722                 }
 723
 724                 *(__u32*) &buffer = buflo;
 725                 *(1 + (__u32*) &buffer) = bufhi;
 726                 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
 727                         return -1; /* fault */
 728                 }
 729                 return 0;
 730         } else {
 731                 die ("Misaligned FPU load inside kernel", regs, 0);
 732                 return -1;
 733         }
 734 }
 735 #endif
 736
 737 static int misaligned_fixup(struct pt_regs *regs)
 738 {
 739         unsigned long opcode;
 740         int error;
 741         int major, minor;
 742
 743 #if !defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 744         /* Never fixup user mode misaligned accesses without this option enabled. */
 745         return -1;
 746 #else
 747         if (!user_mode_unaligned_fixup_enable) return -1;
 748 #endif
 749
 750         error = read_opcode(regs->pc, &opcode, user_mode(regs));
 751         if (error < 0) {
 752                 return error;
 753         }
 754         major = (opcode >> 26) & 0x3f;
 755         minor = (opcode >> 16) & 0xf;
 756
 757 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 758         if (user_mode(regs) && (user_mode_unaligned_fixup_count > 0)) {
 759                 --user_mode_unaligned_fixup_count;
 760                 /* Only do 'count' worth of these reports, to remove a potential DoS against syslog */
 761                 printk("Fixing up unaligned userspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
 762                        current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
 763         } else
 764 #endif
 765         if (!user_mode(regs) && (kernel_mode_unaligned_fixup_count > 0)) {
 766                 --kernel_mode_unaligned_fixup_count;
 767                 if (in_interrupt()) {
 768                         printk("Fixing up unaligned kernelspace access in interrupt pc=0x%08x ins=0x%08lx\n",
 769                                (__u32)regs->pc, opcode);
 770                 } else {
 771                         printk("Fixing up unaligned kernelspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
 772                                current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
 773                 }
 774         }
 775
 776
 777         switch (major) {
 778                 case (0x84>>2): /* LD.W */
 779                         error = misaligned_load(regs, opcode, 1, 1, 1);
 780                         break;
 781                 case (0xb0>>2): /* LD.UW */
 782                         error = misaligned_load(regs, opcode, 1, 1, 0);
 783                         break;
 784                 case (0x88>>2): /* LD.L */
 785                         error = misaligned_load(regs, opcode, 1, 2, 1);
 786                         break;
 787                 case (0x8c>>2): /* LD.Q */
 788                         error = misaligned_load(regs, opcode, 1, 3, 0);
 789                         break;
 790
 791                 case (0xa4>>2): /* ST.W */
 792                         error = misaligned_store(regs, opcode, 1, 1);
 793                         break;
 794                 case (0xa8>>2): /* ST.L */
 795                         error = misaligned_store(regs, opcode, 1, 2);
 796                         break;
 797                 case (0xac>>2): /* ST.Q */
 798                         error = misaligned_store(regs, opcode, 1, 3);
 799                         break;
 800
 801                 case (0x40>>2): /* indexed loads */
 802                         switch (minor) {
 803                                 case 0x1: /* LDX.W */
 804                                         error = misaligned_load(regs, opcode, 0, 1, 1);
 805                                         break;
 806                                 case 0x5: /* LDX.UW */
 807                                         error = misaligned_load(regs, opcode, 0, 1, 0);
 808                                         break;
 809                                 case 0x2: /* LDX.L */
 810                                         error = misaligned_load(regs, opcode, 0, 2, 1);
 811                                         break;
 812                                 case 0x3: /* LDX.Q */
 813                                         error = misaligned_load(regs, opcode, 0, 3, 0);
 814                                         break;
 815                                 default:
 816                                         error = -1;
 817                                         break;
 818                         }
 819                         break;
 820
 821                 case (0x60>>2): /* indexed stores */
 822                         switch (minor) {
 823                                 case 0x1: /* STX.W */
 824                                         error = misaligned_store(regs, opcode, 0, 1);
 825                                         break;
 826                                 case 0x2: /* STX.L */
 827                                         error = misaligned_store(regs, opcode, 0, 2);
 828                                         break;
 829                                 case 0x3: /* STX.Q */
 830                                         error = misaligned_store(regs, opcode, 0, 3);
 831                                         break;
 832                                 default:
 833                                         error = -1;
 834                                         break;
 835                         }
 836                         break;
 837
 838 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 839                 case (0x94>>2): /* FLD.S */
 840                         error = misaligned_fpu_load(regs, opcode, 1, 2, 0);
 841                         break;
 842                 case (0x98>>2): /* FLD.P */
 843                         error = misaligned_fpu_load(regs, opcode, 1, 3, 1);
 844                         break;
 845                 case (0x9c>>2): /* FLD.D */
 846                         error = misaligned_fpu_load(regs, opcode, 1, 3, 0);
 847                         break;
 848                 case (0x1c>>2): /* floating indexed loads */
 849                         switch (minor) {
 850                         case 0x8: /* FLDX.S */
 851                                 error = misaligned_fpu_load(regs, opcode, 0, 2, 0);
 852                                 break;
 853                         case 0xd: /* FLDX.P */
 854                                 error = misaligned_fpu_load(regs, opcode, 0, 3, 1);
 855                                 break;
 856                         case 0x9: /* FLDX.D */
 857                                 error = misaligned_fpu_load(regs, opcode, 0, 3, 0);
 858                                 break;
 859                         default:
 860                                 error = -1;
 861                                 break;
 862                         }
 863                         break;
 864                 case (0xb4>>2): /* FLD.S */
 865                         error = misaligned_fpu_store(regs, opcode, 1, 2, 0);
 866                         break;
 867                 case (0xb8>>2): /* FLD.P */
 868                         error = misaligned_fpu_store(regs, opcode, 1, 3, 1);
 869                         break;
 870                 case (0xbc>>2): /* FLD.D */
 871                         error = misaligned_fpu_store(regs, opcode, 1, 3, 0);
 872                         break;
 873                 case (0x3c>>2): /* floating indexed stores */
 874                         switch (minor) {
 875                         case 0x8: /* FSTX.S */
 876                                 error = misaligned_fpu_store(regs, opcode, 0, 2, 0);
 877                                 break;
 878                         case 0xd: /* FSTX.P */
 879                                 error = misaligned_fpu_store(regs, opcode, 0, 3, 1);
 880                                 break;
 881                         case 0x9: /* FSTX.D */
 882                                 error = misaligned_fpu_store(regs, opcode, 0, 3, 0);
 883                                 break;
 884                         default:
 885                                 error = -1;
 886                                 break;
 887                         }
 888                         break;
 889 #endif
 890
 891                 default:
 892                         /* Fault */
 893                         error = -1;
 894                         break;
 895         }
 896
 897         if (error < 0) {
 898                 return error;
 899         } else {
 900                 regs->pc += 4; /* Skip the instruction that's just been emulated */
 901                 return 0;
 902         }
 903
 904 }
 905
 906 static ctl_table unaligned_table[] = {
 907         {
 908                 .ctl_name       = CTL_UNNUMBERED,
 909                 .procname       = "kernel_reports",
 910                 .data           = &kernel_mode_unaligned_fixup_count,
 911                 .maxlen         = sizeof(int),
 912                 .mode           = 0644,
 913                 .proc_handler   = &proc_dointvec
 914         },
 915 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
 916         {
 917                 .ctl_name       = CTL_UNNUMBERED,
 918                 .procname       = "user_reports",
 919                 .data           = &user_mode_unaligned_fixup_count,
 920                 .maxlen         = sizeof(int),
 921                 .mode           = 0644,
 922                 .proc_handler   = &proc_dointvec
 923         },
 924         {
 925                 .ctl_name       = CTL_UNNUMBERED,
 926                 .procname       = "user_enable",
 927                 .data           = &user_mode_unaligned_fixup_enable,
 928                 .maxlen         = sizeof(int),
 929                 .mode           = 0644,
 930                 .proc_handler   = &proc_dointvec},
 931 #endif
 932         {}
 933 };
 934
 935 static ctl_table unaligned_root[] = {
 936         {
 937                 .ctl_name       = CTL_UNNUMBERED,
 938                 .procname       = "unaligned_fixup",
 939                 .mode           = 0555,
 940                 unaligned_table
 941         },
 942         {}
 943 };
 944
 945 static ctl_table sh64_root[] = {
 946         {
 947                 .ctl_name       = CTL_UNNUMBERED,
 948                 .procname       = "sh64",
 949                 .mode           = 0555,
 950                 .child          = unaligned_root
 951         },
 952         {}
 953 };
 954 static struct ctl_table_header *sysctl_header;
 955 static int __init init_sysctl(void)
 956 {
 957         sysctl_header = register_sysctl_table(sh64_root);
 958         return 0;
 959 }
 960
 961 __initcall(init_sysctl);
 962
 963
 964 asmlinkage void do_debug_interrupt(unsigned long code, struct pt_regs *regs)
 965 {
 966         u64 peek_real_address_q(u64 addr);
 967         u64 poke_real_address_q(u64 addr, u64 val);
 968         unsigned long long DM_EXP_CAUSE_PHY = 0x0c100010;
 969         unsigned long long exp_cause;
 970         /* It's not worth ioremapping the debug module registers for the amount
 971            of access we make to them - just go direct to their physical
 972            addresses. */
 973         exp_cause = peek_real_address_q(DM_EXP_CAUSE_PHY);
 974         if (exp_cause & ~4) {
 975                 printk("DM.EXP_CAUSE had unexpected bits set (=%08lx)\n",
 976                         (unsigned long)(exp_cause & 0xffffffff));
 977         }
 978         show_state();
 979         /* Clear all DEBUGINT causes */
 980         poke_real_address_q(DM_EXP_CAUSE_PHY, 0x0);
 981 }