1 /* align.c - handle alignment exceptions for the Power PC. 2 * 3 * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au> 4 * Copyright (c) 1998-1999 TiVo, Inc. 5 * PowerPC 403GCX modifications. 6 * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu> 7 * PowerPC 403GCX/405GP modifications. 8 * Copyright (c) 2001-2002 PPC64 team, IBM Corp 9 * 64-bit and Power4 support 10 * Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp 11 * <benh@kernel.crashing.org> 12 * Merge ppc32 and ppc64 implementations 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 */ 19 20 #include <linux/kernel.h> 21 #include <linux/mm.h> 22 #include <asm/processor.h> 23 #include <asm/uaccess.h> 24 #include <asm/cache.h> 25 #include <asm/cputable.h> 26 #include <asm/emulated_ops.h> 27 #include <asm/switch_to.h> 28 29 struct aligninfo { 30 unsigned char len; 31 unsigned char flags; 32 }; 33 34 #define IS_XFORM(inst) (((inst) >> 26) == 31) 35 #define IS_DSFORM(inst) (((inst) >> 26) >= 56) 36 37 #define INVALID { 0, 0 } 38 39 /* Bits in the flags field */ 40 #define LD 0 /* load */ 41 #define ST 1 /* store */ 42 #define SE 2 /* sign-extend value, or FP ld/st as word */ 43 #define F 4 /* to/from fp regs */ 44 #define U 8 /* update index register */ 45 #define M 0x10 /* multiple load/store */ 46 #define SW 0x20 /* byte swap */ 47 #define S 0x40 /* single-precision fp or... */ 48 #define SX 0x40 /* ... byte count in XER */ 49 #define HARD 0x80 /* string, stwcx. */ 50 #define E4 0x40 /* SPE endianness is word */ 51 #define E8 0x80 /* SPE endianness is double word */ 52 #define SPLT 0x80 /* VSX SPLAT load */ 53 54 /* DSISR bits reported for a DCBZ instruction: */ 55 #define DCBZ 0x5f /* 8xx/82xx dcbz faults when cache not enabled */ 56 57 #define SWAP(a, b) (t = (a), (a) = (b), (b) = t) 58 59 /* 60 * The PowerPC stores certain bits of the instruction that caused the 61 * alignment exception in the DSISR register. This array maps those 62 * bits to information about the operand length and what the 63 * instruction would do. 64 */ 65 static struct aligninfo aligninfo[128] = { 66 { 4, LD }, /* 00 0 0000: lwz / lwarx */ 67 INVALID, /* 00 0 0001 */ 68 { 4, ST }, /* 00 0 0010: stw */ 69 INVALID, /* 00 0 0011 */ 70 { 2, LD }, /* 00 0 0100: lhz */ 71 { 2, LD+SE }, /* 00 0 0101: lha */ 72 { 2, ST }, /* 00 0 0110: sth */ 73 { 4, LD+M }, /* 00 0 0111: lmw */ 74 { 4, LD+F+S }, /* 00 0 1000: lfs */ 75 { 8, LD+F }, /* 00 0 1001: lfd */ 76 { 4, ST+F+S }, /* 00 0 1010: stfs */ 77 { 8, ST+F }, /* 00 0 1011: stfd */ 78 INVALID, /* 00 0 1100 */ 79 { 8, LD }, /* 00 0 1101: ld/ldu/lwa */ 80 INVALID, /* 00 0 1110 */ 81 { 8, ST }, /* 00 0 1111: std/stdu */ 82 { 4, LD+U }, /* 00 1 0000: lwzu */ 83 INVALID, /* 00 1 0001 */ 84 { 4, ST+U }, /* 00 1 0010: stwu */ 85 INVALID, /* 00 1 0011 */ 86 { 2, LD+U }, /* 00 1 0100: lhzu */ 87 { 2, LD+SE+U }, /* 00 1 0101: lhau */ 88 { 2, ST+U }, /* 00 1 0110: sthu */ 89 { 4, ST+M }, /* 00 1 0111: stmw */ 90 { 4, LD+F+S+U }, /* 00 1 1000: lfsu */ 91 { 8, LD+F+U }, /* 00 1 1001: lfdu */ 92 { 4, ST+F+S+U }, /* 00 1 1010: stfsu */ 93 { 8, ST+F+U }, /* 00 1 1011: stfdu */ 94 { 16, LD+F }, /* 00 1 1100: lfdp */ 95 INVALID, /* 00 1 1101 */ 96 { 16, ST+F }, /* 00 1 1110: stfdp */ 97 INVALID, /* 00 1 1111 */ 98 { 8, LD }, /* 01 0 0000: ldx */ 99 INVALID, /* 01 0 0001 */ 100 { 8, ST }, /* 01 0 0010: stdx */ 101 INVALID, /* 01 0 0011 */ 102 INVALID, /* 01 0 0100 */ 103 { 4, LD+SE }, /* 01 0 0101: lwax */ 104 INVALID, /* 01 0 0110 */ 105 INVALID, /* 01 0 0111 */ 106 { 4, LD+M+HARD+SX }, /* 01 0 1000: lswx */ 107 { 4, LD+M+HARD }, /* 01 0 1001: lswi */ 108 { 4, ST+M+HARD+SX }, /* 01 0 1010: stswx */ 109 { 4, ST+M+HARD }, /* 01 0 1011: stswi */ 110 INVALID, /* 01 0 1100 */ 111 { 8, LD+U }, /* 01 0 1101: ldu */ 112 INVALID, /* 01 0 1110 */ 113 { 8, ST+U }, /* 01 0 1111: stdu */ 114 { 8, LD+U }, /* 01 1 0000: ldux */ 115 INVALID, /* 01 1 0001 */ 116 { 8, ST+U }, /* 01 1 0010: stdux */ 117 INVALID, /* 01 1 0011 */ 118 INVALID, /* 01 1 0100 */ 119 { 4, LD+SE+U }, /* 01 1 0101: lwaux */ 120 INVALID, /* 01 1 0110 */ 121 INVALID, /* 01 1 0111 */ 122 INVALID, /* 01 1 1000 */ 123 INVALID, /* 01 1 1001 */ 124 INVALID, /* 01 1 1010 */ 125 INVALID, /* 01 1 1011 */ 126 INVALID, /* 01 1 1100 */ 127 INVALID, /* 01 1 1101 */ 128 INVALID, /* 01 1 1110 */ 129 INVALID, /* 01 1 1111 */ 130 INVALID, /* 10 0 0000 */ 131 INVALID, /* 10 0 0001 */ 132 INVALID, /* 10 0 0010: stwcx. */ 133 INVALID, /* 10 0 0011 */ 134 INVALID, /* 10 0 0100 */ 135 INVALID, /* 10 0 0101 */ 136 INVALID, /* 10 0 0110 */ 137 INVALID, /* 10 0 0111 */ 138 { 4, LD+SW }, /* 10 0 1000: lwbrx */ 139 INVALID, /* 10 0 1001 */ 140 { 4, ST+SW }, /* 10 0 1010: stwbrx */ 141 INVALID, /* 10 0 1011 */ 142 { 2, LD+SW }, /* 10 0 1100: lhbrx */ 143 { 4, LD+SE }, /* 10 0 1101 lwa */ 144 { 2, ST+SW }, /* 10 0 1110: sthbrx */ 145 INVALID, /* 10 0 1111 */ 146 INVALID, /* 10 1 0000 */ 147 INVALID, /* 10 1 0001 */ 148 INVALID, /* 10 1 0010 */ 149 INVALID, /* 10 1 0011 */ 150 INVALID, /* 10 1 0100 */ 151 INVALID, /* 10 1 0101 */ 152 INVALID, /* 10 1 0110 */ 153 INVALID, /* 10 1 0111 */ 154 INVALID, /* 10 1 1000 */ 155 INVALID, /* 10 1 1001 */ 156 INVALID, /* 10 1 1010 */ 157 INVALID, /* 10 1 1011 */ 158 INVALID, /* 10 1 1100 */ 159 INVALID, /* 10 1 1101 */ 160 INVALID, /* 10 1 1110 */ 161 { 0, ST+HARD }, /* 10 1 1111: dcbz */ 162 { 4, LD }, /* 11 0 0000: lwzx */ 163 INVALID, /* 11 0 0001 */ 164 { 4, ST }, /* 11 0 0010: stwx */ 165 INVALID, /* 11 0 0011 */ 166 { 2, LD }, /* 11 0 0100: lhzx */ 167 { 2, LD+SE }, /* 11 0 0101: lhax */ 168 { 2, ST }, /* 11 0 0110: sthx */ 169 INVALID, /* 11 0 0111 */ 170 { 4, LD+F+S }, /* 11 0 1000: lfsx */ 171 { 8, LD+F }, /* 11 0 1001: lfdx */ 172 { 4, ST+F+S }, /* 11 0 1010: stfsx */ 173 { 8, ST+F }, /* 11 0 1011: stfdx */ 174 { 16, LD+F }, /* 11 0 1100: lfdpx */ 175 { 4, LD+F+SE }, /* 11 0 1101: lfiwax */ 176 { 16, ST+F }, /* 11 0 1110: stfdpx */ 177 { 4, ST+F }, /* 11 0 1111: stfiwx */ 178 { 4, LD+U }, /* 11 1 0000: lwzux */ 179 INVALID, /* 11 1 0001 */ 180 { 4, ST+U }, /* 11 1 0010: stwux */ 181 INVALID, /* 11 1 0011 */ 182 { 2, LD+U }, /* 11 1 0100: lhzux */ 183 { 2, LD+SE+U }, /* 11 1 0101: lhaux */ 184 { 2, ST+U }, /* 11 1 0110: sthux */ 185 INVALID, /* 11 1 0111 */ 186 { 4, LD+F+S+U }, /* 11 1 1000: lfsux */ 187 { 8, LD+F+U }, /* 11 1 1001: lfdux */ 188 { 4, ST+F+S+U }, /* 11 1 1010: stfsux */ 189 { 8, ST+F+U }, /* 11 1 1011: stfdux */ 190 INVALID, /* 11 1 1100 */ 191 { 4, LD+F }, /* 11 1 1101: lfiwzx */ 192 INVALID, /* 11 1 1110 */ 193 INVALID, /* 11 1 1111 */ 194 }; 195 196 /* 197 * Create a DSISR value from the instruction 198 */ 199 static inline unsigned make_dsisr(unsigned instr) 200 { 201 unsigned dsisr; 202 203 204 /* bits 6:15 --> 22:31 */ 205 dsisr = (instr & 0x03ff0000) >> 16; 206 207 if (IS_XFORM(instr)) { 208 /* bits 29:30 --> 15:16 */ 209 dsisr |= (instr & 0x00000006) << 14; 210 /* bit 25 --> 17 */ 211 dsisr |= (instr & 0x00000040) << 8; 212 /* bits 21:24 --> 18:21 */ 213 dsisr |= (instr & 0x00000780) << 3; 214 } else { 215 /* bit 5 --> 17 */ 216 dsisr |= (instr & 0x04000000) >> 12; 217 /* bits 1: 4 --> 18:21 */ 218 dsisr |= (instr & 0x78000000) >> 17; 219 /* bits 30:31 --> 12:13 */ 220 if (IS_DSFORM(instr)) 221 dsisr |= (instr & 0x00000003) << 18; 222 } 223 224 return dsisr; 225 } 226 227 /* 228 * The dcbz (data cache block zero) instruction 229 * gives an alignment fault if used on non-cacheable 230 * memory. We handle the fault mainly for the 231 * case when we are running with the cache disabled 232 * for debugging. 233 */ 234 static int emulate_dcbz(struct pt_regs *regs, unsigned char __user *addr) 235 { 236 long __user *p; 237 int i, size; 238 239 #ifdef __powerpc64__ 240 size = ppc64_caches.dline_size; 241 #else 242 size = L1_CACHE_BYTES; 243 #endif 244 p = (long __user *) (regs->dar & -size); 245 if (user_mode(regs) && !access_ok(VERIFY_WRITE, p, size)) 246 return -EFAULT; 247 for (i = 0; i < size / sizeof(long); ++i) 248 if (__put_user_inatomic(0, p+i)) 249 return -EFAULT; 250 return 1; 251 } 252 253 /* 254 * Emulate load & store multiple instructions 255 * On 64-bit machines, these instructions only affect/use the 256 * bottom 4 bytes of each register, and the loads clear the 257 * top 4 bytes of the affected register. 258 */ 259 #ifdef CONFIG_PPC64 260 #define REG_BYTE(rp, i) *((u8 *)((rp) + ((i) >> 2)) + ((i) & 3) + 4) 261 #else 262 #define REG_BYTE(rp, i) *((u8 *)(rp) + (i)) 263 #endif 264 265 #define SWIZ_PTR(p) ((unsigned char __user *)((p) ^ swiz)) 266 267 static int emulate_multiple(struct pt_regs *regs, unsigned char __user *addr, 268 unsigned int reg, unsigned int nb, 269 unsigned int flags, unsigned int instr, 270 unsigned long swiz) 271 { 272 unsigned long *rptr; 273 unsigned int nb0, i, bswiz; 274 unsigned long p; 275 276 /* 277 * We do not try to emulate 8 bytes multiple as they aren't really 278 * available in our operating environments and we don't try to 279 * emulate multiples operations in kernel land as they should never 280 * be used/generated there at least not on unaligned boundaries 281 */ 282 if (unlikely((nb > 4) || !user_mode(regs))) 283 return 0; 284 285 /* lmw, stmw, lswi/x, stswi/x */ 286 nb0 = 0; 287 if (flags & HARD) { 288 if (flags & SX) { 289 nb = regs->xer & 127; 290 if (nb == 0) 291 return 1; 292 } else { 293 unsigned long pc = regs->nip ^ (swiz & 4); 294 295 if (__get_user_inatomic(instr, 296 (unsigned int __user *)pc)) 297 return -EFAULT; 298 if (swiz == 0 && (flags & SW)) 299 instr = cpu_to_le32(instr); 300 nb = (instr >> 11) & 0x1f; 301 if (nb == 0) 302 nb = 32; 303 } 304 if (nb + reg * 4 > 128) { 305 nb0 = nb + reg * 4 - 128; 306 nb = 128 - reg * 4; 307 } 308 } else { 309 /* lwm, stmw */ 310 nb = (32 - reg) * 4; 311 } 312 313 if (!access_ok((flags & ST ? VERIFY_WRITE: VERIFY_READ), addr, nb+nb0)) 314 return -EFAULT; /* bad address */ 315 316 rptr = ®s->gpr[reg]; 317 p = (unsigned long) addr; 318 bswiz = (flags & SW)? 3: 0; 319 320 if (!(flags & ST)) { 321 /* 322 * This zeroes the top 4 bytes of the affected registers 323 * in 64-bit mode, and also zeroes out any remaining 324 * bytes of the last register for lsw*. 325 */ 326 memset(rptr, 0, ((nb + 3) / 4) * sizeof(unsigned long)); 327 if (nb0 > 0) 328 memset(®s->gpr[0], 0, 329 ((nb0 + 3) / 4) * sizeof(unsigned long)); 330 331 for (i = 0; i < nb; ++i, ++p) 332 if (__get_user_inatomic(REG_BYTE(rptr, i ^ bswiz), 333 SWIZ_PTR(p))) 334 return -EFAULT; 335 if (nb0 > 0) { 336 rptr = ®s->gpr[0]; 337 addr += nb; 338 for (i = 0; i < nb0; ++i, ++p) 339 if (__get_user_inatomic(REG_BYTE(rptr, 340 i ^ bswiz), 341 SWIZ_PTR(p))) 342 return -EFAULT; 343 } 344 345 } else { 346 for (i = 0; i < nb; ++i, ++p) 347 if (__put_user_inatomic(REG_BYTE(rptr, i ^ bswiz), 348 SWIZ_PTR(p))) 349 return -EFAULT; 350 if (nb0 > 0) { 351 rptr = ®s->gpr[0]; 352 addr += nb; 353 for (i = 0; i < nb0; ++i, ++p) 354 if (__put_user_inatomic(REG_BYTE(rptr, 355 i ^ bswiz), 356 SWIZ_PTR(p))) 357 return -EFAULT; 358 } 359 } 360 return 1; 361 } 362 363 /* 364 * Emulate floating-point pair loads and stores. 365 * Only POWER6 has these instructions, and it does true little-endian, 366 * so we don't need the address swizzling. 367 */ 368 static int emulate_fp_pair(unsigned char __user *addr, unsigned int reg, 369 unsigned int flags) 370 { 371 char *ptr0 = (char *) ¤t->thread.TS_FPR(reg); 372 char *ptr1 = (char *) ¤t->thread.TS_FPR(reg+1); 373 int i, ret, sw = 0; 374 375 if (!(flags & F)) 376 return 0; 377 if (reg & 1) 378 return 0; /* invalid form: FRS/FRT must be even */ 379 if (flags & SW) 380 sw = 7; 381 ret = 0; 382 for (i = 0; i < 8; ++i) { 383 if (!(flags & ST)) { 384 ret |= __get_user(ptr0[i^sw], addr + i); 385 ret |= __get_user(ptr1[i^sw], addr + i + 8); 386 } else { 387 ret |= __put_user(ptr0[i^sw], addr + i); 388 ret |= __put_user(ptr1[i^sw], addr + i + 8); 389 } 390 } 391 if (ret) 392 return -EFAULT; 393 return 1; /* exception handled and fixed up */ 394 } 395 396 #ifdef CONFIG_SPE 397 398 static struct aligninfo spe_aligninfo[32] = { 399 { 8, LD+E8 }, /* 0 00 00: evldd[x] */ 400 { 8, LD+E4 }, /* 0 00 01: evldw[x] */ 401 { 8, LD }, /* 0 00 10: evldh[x] */ 402 INVALID, /* 0 00 11 */ 403 { 2, LD }, /* 0 01 00: evlhhesplat[x] */ 404 INVALID, /* 0 01 01 */ 405 { 2, LD }, /* 0 01 10: evlhhousplat[x] */ 406 { 2, LD+SE }, /* 0 01 11: evlhhossplat[x] */ 407 { 4, LD }, /* 0 10 00: evlwhe[x] */ 408 INVALID, /* 0 10 01 */ 409 { 4, LD }, /* 0 10 10: evlwhou[x] */ 410 { 4, LD+SE }, /* 0 10 11: evlwhos[x] */ 411 { 4, LD+E4 }, /* 0 11 00: evlwwsplat[x] */ 412 INVALID, /* 0 11 01 */ 413 { 4, LD }, /* 0 11 10: evlwhsplat[x] */ 414 INVALID, /* 0 11 11 */ 415 416 { 8, ST+E8 }, /* 1 00 00: evstdd[x] */ 417 { 8, ST+E4 }, /* 1 00 01: evstdw[x] */ 418 { 8, ST }, /* 1 00 10: evstdh[x] */ 419 INVALID, /* 1 00 11 */ 420 INVALID, /* 1 01 00 */ 421 INVALID, /* 1 01 01 */ 422 INVALID, /* 1 01 10 */ 423 INVALID, /* 1 01 11 */ 424 { 4, ST }, /* 1 10 00: evstwhe[x] */ 425 INVALID, /* 1 10 01 */ 426 { 4, ST }, /* 1 10 10: evstwho[x] */ 427 INVALID, /* 1 10 11 */ 428 { 4, ST+E4 }, /* 1 11 00: evstwwe[x] */ 429 INVALID, /* 1 11 01 */ 430 { 4, ST+E4 }, /* 1 11 10: evstwwo[x] */ 431 INVALID, /* 1 11 11 */ 432 }; 433 434 #define EVLDD 0x00 435 #define EVLDW 0x01 436 #define EVLDH 0x02 437 #define EVLHHESPLAT 0x04 438 #define EVLHHOUSPLAT 0x06 439 #define EVLHHOSSPLAT 0x07 440 #define EVLWHE 0x08 441 #define EVLWHOU 0x0A 442 #define EVLWHOS 0x0B 443 #define EVLWWSPLAT 0x0C 444 #define EVLWHSPLAT 0x0E 445 #define EVSTDD 0x10 446 #define EVSTDW 0x11 447 #define EVSTDH 0x12 448 #define EVSTWHE 0x18 449 #define EVSTWHO 0x1A 450 #define EVSTWWE 0x1C 451 #define EVSTWWO 0x1E 452 453 /* 454 * Emulate SPE loads and stores. 455 * Only Book-E has these instructions, and it does true little-endian, 456 * so we don't need the address swizzling. 457 */ 458 static int emulate_spe(struct pt_regs *regs, unsigned int reg, 459 unsigned int instr) 460 { 461 int t, ret; 462 union { 463 u64 ll; 464 u32 w[2]; 465 u16 h[4]; 466 u8 v[8]; 467 } data, temp; 468 unsigned char __user *p, *addr; 469 unsigned long *evr = ¤t->thread.evr[reg]; 470 unsigned int nb, flags; 471 472 instr = (instr >> 1) & 0x1f; 473 474 /* DAR has the operand effective address */ 475 addr = (unsigned char __user *)regs->dar; 476 477 nb = spe_aligninfo[instr].len; 478 flags = spe_aligninfo[instr].flags; 479 480 /* Verify the address of the operand */ 481 if (unlikely(user_mode(regs) && 482 !access_ok((flags & ST ? VERIFY_WRITE : VERIFY_READ), 483 addr, nb))) 484 return -EFAULT; 485 486 /* userland only */ 487 if (unlikely(!user_mode(regs))) 488 return 0; 489 490 flush_spe_to_thread(current); 491 492 /* If we are loading, get the data from user space, else 493 * get it from register values 494 */ 495 if (flags & ST) { 496 data.ll = 0; 497 switch (instr) { 498 case EVSTDD: 499 case EVSTDW: 500 case EVSTDH: 501 data.w[0] = *evr; 502 data.w[1] = regs->gpr[reg]; 503 break; 504 case EVSTWHE: 505 data.h[2] = *evr >> 16; 506 data.h[3] = regs->gpr[reg] >> 16; 507 break; 508 case EVSTWHO: 509 data.h[2] = *evr & 0xffff; 510 data.h[3] = regs->gpr[reg] & 0xffff; 511 break; 512 case EVSTWWE: 513 data.w[1] = *evr; 514 break; 515 case EVSTWWO: 516 data.w[1] = regs->gpr[reg]; 517 break; 518 default: 519 return -EINVAL; 520 } 521 } else { 522 temp.ll = data.ll = 0; 523 ret = 0; 524 p = addr; 525 526 switch (nb) { 527 case 8: 528 ret |= __get_user_inatomic(temp.v[0], p++); 529 ret |= __get_user_inatomic(temp.v[1], p++); 530 ret |= __get_user_inatomic(temp.v[2], p++); 531 ret |= __get_user_inatomic(temp.v[3], p++); 532 case 4: 533 ret |= __get_user_inatomic(temp.v[4], p++); 534 ret |= __get_user_inatomic(temp.v[5], p++); 535 case 2: 536 ret |= __get_user_inatomic(temp.v[6], p++); 537 ret |= __get_user_inatomic(temp.v[7], p++); 538 if (unlikely(ret)) 539 return -EFAULT; 540 } 541 542 switch (instr) { 543 case EVLDD: 544 case EVLDW: 545 case EVLDH: 546 data.ll = temp.ll; 547 break; 548 case EVLHHESPLAT: 549 data.h[0] = temp.h[3]; 550 data.h[2] = temp.h[3]; 551 break; 552 case EVLHHOUSPLAT: 553 case EVLHHOSSPLAT: 554 data.h[1] = temp.h[3]; 555 data.h[3] = temp.h[3]; 556 break; 557 case EVLWHE: 558 data.h[0] = temp.h[2]; 559 data.h[2] = temp.h[3]; 560 break; 561 case EVLWHOU: 562 case EVLWHOS: 563 data.h[1] = temp.h[2]; 564 data.h[3] = temp.h[3]; 565 break; 566 case EVLWWSPLAT: 567 data.w[0] = temp.w[1]; 568 data.w[1] = temp.w[1]; 569 break; 570 case EVLWHSPLAT: 571 data.h[0] = temp.h[2]; 572 data.h[1] = temp.h[2]; 573 data.h[2] = temp.h[3]; 574 data.h[3] = temp.h[3]; 575 break; 576 default: 577 return -EINVAL; 578 } 579 } 580 581 if (flags & SW) { 582 switch (flags & 0xf0) { 583 case E8: 584 SWAP(data.v[0], data.v[7]); 585 SWAP(data.v[1], data.v[6]); 586 SWAP(data.v[2], data.v[5]); 587 SWAP(data.v[3], data.v[4]); 588 break; 589 case E4: 590 591 SWAP(data.v[0], data.v[3]); 592 SWAP(data.v[1], data.v[2]); 593 SWAP(data.v[4], data.v[7]); 594 SWAP(data.v[5], data.v[6]); 595 break; 596 /* Its half word endian */ 597 default: 598 SWAP(data.v[0], data.v[1]); 599 SWAP(data.v[2], data.v[3]); 600 SWAP(data.v[4], data.v[5]); 601 SWAP(data.v[6], data.v[7]); 602 break; 603 } 604 } 605 606 if (flags & SE) { 607 data.w[0] = (s16)data.h[1]; 608 data.w[1] = (s16)data.h[3]; 609 } 610 611 /* Store result to memory or update registers */ 612 if (flags & ST) { 613 ret = 0; 614 p = addr; 615 switch (nb) { 616 case 8: 617 ret |= __put_user_inatomic(data.v[0], p++); 618 ret |= __put_user_inatomic(data.v[1], p++); 619 ret |= __put_user_inatomic(data.v[2], p++); 620 ret |= __put_user_inatomic(data.v[3], p++); 621 case 4: 622 ret |= __put_user_inatomic(data.v[4], p++); 623 ret |= __put_user_inatomic(data.v[5], p++); 624 case 2: 625 ret |= __put_user_inatomic(data.v[6], p++); 626 ret |= __put_user_inatomic(data.v[7], p++); 627 } 628 if (unlikely(ret)) 629 return -EFAULT; 630 } else { 631 *evr = data.w[0]; 632 regs->gpr[reg] = data.w[1]; 633 } 634 635 return 1; 636 } 637 #endif /* CONFIG_SPE */ 638 639 #ifdef CONFIG_VSX 640 /* 641 * Emulate VSX instructions... 642 */ 643 static int emulate_vsx(unsigned char __user *addr, unsigned int reg, 644 unsigned int areg, struct pt_regs *regs, 645 unsigned int flags, unsigned int length, 646 unsigned int elsize) 647 { 648 char *ptr; 649 unsigned long *lptr; 650 int ret = 0; 651 int sw = 0; 652 int i, j; 653 654 /* userland only */ 655 if (unlikely(!user_mode(regs))) 656 return 0; 657 658 flush_vsx_to_thread(current); 659 660 if (reg < 32) 661 ptr = (char *) ¤t->thread.TS_FPR(reg); 662 else 663 ptr = (char *) ¤t->thread.vr[reg - 32]; 664 665 lptr = (unsigned long *) ptr; 666 667 if (flags & SW) 668 sw = elsize-1; 669 670 for (j = 0; j < length; j += elsize) { 671 for (i = 0; i < elsize; ++i) { 672 if (flags & ST) 673 ret |= __put_user(ptr[i^sw], addr + i); 674 else 675 ret |= __get_user(ptr[i^sw], addr + i); 676 } 677 ptr += elsize; 678 addr += elsize; 679 } 680 681 if (!ret) { 682 if (flags & U) 683 regs->gpr[areg] = regs->dar; 684 685 /* Splat load copies the same data to top and bottom 8 bytes */ 686 if (flags & SPLT) 687 lptr[1] = lptr[0]; 688 /* For 8 byte loads, zero the top 8 bytes */ 689 else if (!(flags & ST) && (8 == length)) 690 lptr[1] = 0; 691 } else 692 return -EFAULT; 693 694 return 1; 695 } 696 #endif 697 698 /* 699 * Called on alignment exception. Attempts to fixup 700 * 701 * Return 1 on success 702 * Return 0 if unable to handle the interrupt 703 * Return -EFAULT if data address is bad 704 */ 705 706 int fix_alignment(struct pt_regs *regs) 707 { 708 unsigned int instr, nb, flags, instruction = 0; 709 unsigned int reg, areg; 710 unsigned int dsisr; 711 unsigned char __user *addr; 712 unsigned long p, swiz; 713 int ret, t; 714 union { 715 u64 ll; 716 double dd; 717 unsigned char v[8]; 718 struct { 719 unsigned hi32; 720 int low32; 721 } x32; 722 struct { 723 unsigned char hi48[6]; 724 short low16; 725 } x16; 726 } data; 727 728 /* 729 * We require a complete register set, if not, then our assembly 730 * is broken 731 */ 732 CHECK_FULL_REGS(regs); 733 734 dsisr = regs->dsisr; 735 736 /* Some processors don't provide us with a DSISR we can use here, 737 * let's make one up from the instruction 738 */ 739 if (cpu_has_feature(CPU_FTR_NODSISRALIGN)) { 740 unsigned long pc = regs->nip; 741 742 if (cpu_has_feature(CPU_FTR_PPC_LE) && (regs->msr & MSR_LE)) 743 pc ^= 4; 744 if (unlikely(__get_user_inatomic(instr, 745 (unsigned int __user *)pc))) 746 return -EFAULT; 747 if (cpu_has_feature(CPU_FTR_REAL_LE) && (regs->msr & MSR_LE)) 748 instr = cpu_to_le32(instr); 749 dsisr = make_dsisr(instr); 750 instruction = instr; 751 } 752 753 /* extract the operation and registers from the dsisr */ 754 reg = (dsisr >> 5) & 0x1f; /* source/dest register */ 755 areg = dsisr & 0x1f; /* register to update */ 756 757 #ifdef CONFIG_SPE 758 if ((instr >> 26) == 0x4) { 759 PPC_WARN_ALIGNMENT(spe, regs); 760 return emulate_spe(regs, reg, instr); 761 } 762 #endif 763 764 instr = (dsisr >> 10) & 0x7f; 765 instr |= (dsisr >> 13) & 0x60; 766 767 /* Lookup the operation in our table */ 768 nb = aligninfo[instr].len; 769 flags = aligninfo[instr].flags; 770 771 /* ldbrx/stdbrx overlap lfs/stfs in the DSISR unfortunately */ 772 if (IS_XFORM(instruction) && ((instruction >> 1) & 0x3ff) == 532) { 773 nb = 8; 774 flags = LD+SW; 775 } else if (IS_XFORM(instruction) && 776 ((instruction >> 1) & 0x3ff) == 660) { 777 nb = 8; 778 flags = ST+SW; 779 } 780 781 /* Byteswap little endian loads and stores */ 782 swiz = 0; 783 if (regs->msr & MSR_LE) { 784 flags ^= SW; 785 /* 786 * So-called "PowerPC little endian" mode works by 787 * swizzling addresses rather than by actually doing 788 * any byte-swapping. To emulate this, we XOR each 789 * byte address with 7. We also byte-swap, because 790 * the processor's address swizzling depends on the 791 * operand size (it xors the address with 7 for bytes, 792 * 6 for halfwords, 4 for words, 0 for doublewords) but 793 * we will xor with 7 and load/store each byte separately. 794 */ 795 if (cpu_has_feature(CPU_FTR_PPC_LE)) 796 swiz = 7; 797 } 798 799 /* DAR has the operand effective address */ 800 addr = (unsigned char __user *)regs->dar; 801 802 #ifdef CONFIG_VSX 803 if ((instruction & 0xfc00003e) == 0x7c000018) { 804 unsigned int elsize; 805 806 /* Additional register addressing bit (64 VSX vs 32 FPR/GPR) */ 807 reg |= (instruction & 0x1) << 5; 808 /* Simple inline decoder instead of a table */ 809 /* VSX has only 8 and 16 byte memory accesses */ 810 nb = 8; 811 if (instruction & 0x200) 812 nb = 16; 813 814 /* Vector stores in little-endian mode swap individual 815 elements, so process them separately */ 816 elsize = 4; 817 if (instruction & 0x80) 818 elsize = 8; 819 820 flags = 0; 821 if (regs->msr & MSR_LE) 822 flags |= SW; 823 if (instruction & 0x100) 824 flags |= ST; 825 if (instruction & 0x040) 826 flags |= U; 827 /* splat load needs a special decoder */ 828 if ((instruction & 0x400) == 0){ 829 flags |= SPLT; 830 nb = 8; 831 } 832 PPC_WARN_ALIGNMENT(vsx, regs); 833 return emulate_vsx(addr, reg, areg, regs, flags, nb, elsize); 834 } 835 #endif 836 /* A size of 0 indicates an instruction we don't support, with 837 * the exception of DCBZ which is handled as a special case here 838 */ 839 if (instr == DCBZ) { 840 PPC_WARN_ALIGNMENT(dcbz, regs); 841 return emulate_dcbz(regs, addr); 842 } 843 if (unlikely(nb == 0)) 844 return 0; 845 846 /* Load/Store Multiple instructions are handled in their own 847 * function 848 */ 849 if (flags & M) { 850 PPC_WARN_ALIGNMENT(multiple, regs); 851 return emulate_multiple(regs, addr, reg, nb, 852 flags, instr, swiz); 853 } 854 855 /* Verify the address of the operand */ 856 if (unlikely(user_mode(regs) && 857 !access_ok((flags & ST ? VERIFY_WRITE : VERIFY_READ), 858 addr, nb))) 859 return -EFAULT; 860 861 /* Force the fprs into the save area so we can reference them */ 862 if (flags & F) { 863 /* userland only */ 864 if (unlikely(!user_mode(regs))) 865 return 0; 866 flush_fp_to_thread(current); 867 } 868 869 /* Special case for 16-byte FP loads and stores */ 870 if (nb == 16) { 871 PPC_WARN_ALIGNMENT(fp_pair, regs); 872 return emulate_fp_pair(addr, reg, flags); 873 } 874 875 PPC_WARN_ALIGNMENT(unaligned, regs); 876 877 /* If we are loading, get the data from user space, else 878 * get it from register values 879 */ 880 if (!(flags & ST)) { 881 data.ll = 0; 882 ret = 0; 883 p = (unsigned long) addr; 884 switch (nb) { 885 case 8: 886 ret |= __get_user_inatomic(data.v[0], SWIZ_PTR(p++)); 887 ret |= __get_user_inatomic(data.v[1], SWIZ_PTR(p++)); 888 ret |= __get_user_inatomic(data.v[2], SWIZ_PTR(p++)); 889 ret |= __get_user_inatomic(data.v[3], SWIZ_PTR(p++)); 890 case 4: 891 ret |= __get_user_inatomic(data.v[4], SWIZ_PTR(p++)); 892 ret |= __get_user_inatomic(data.v[5], SWIZ_PTR(p++)); 893 case 2: 894 ret |= __get_user_inatomic(data.v[6], SWIZ_PTR(p++)); 895 ret |= __get_user_inatomic(data.v[7], SWIZ_PTR(p++)); 896 if (unlikely(ret)) 897 return -EFAULT; 898 } 899 } else if (flags & F) { 900 data.dd = current->thread.TS_FPR(reg); 901 if (flags & S) { 902 /* Single-precision FP store requires conversion... */ 903 #ifdef CONFIG_PPC_FPU 904 preempt_disable(); 905 enable_kernel_fp(); 906 cvt_df(&data.dd, (float *)&data.v[4]); 907 preempt_enable(); 908 #else 909 return 0; 910 #endif 911 } 912 } else 913 data.ll = regs->gpr[reg]; 914 915 if (flags & SW) { 916 switch (nb) { 917 case 8: 918 SWAP(data.v[0], data.v[7]); 919 SWAP(data.v[1], data.v[6]); 920 SWAP(data.v[2], data.v[5]); 921 SWAP(data.v[3], data.v[4]); 922 break; 923 case 4: 924 SWAP(data.v[4], data.v[7]); 925 SWAP(data.v[5], data.v[6]); 926 break; 927 case 2: 928 SWAP(data.v[6], data.v[7]); 929 break; 930 } 931 } 932 933 /* Perform other misc operations like sign extension 934 * or floating point single precision conversion 935 */ 936 switch (flags & ~(U|SW)) { 937 case LD+SE: /* sign extending integer loads */ 938 case LD+F+SE: /* sign extend for lfiwax */ 939 if ( nb == 2 ) 940 data.ll = data.x16.low16; 941 else /* nb must be 4 */ 942 data.ll = data.x32.low32; 943 break; 944 945 /* Single-precision FP load requires conversion... */ 946 case LD+F+S: 947 #ifdef CONFIG_PPC_FPU 948 preempt_disable(); 949 enable_kernel_fp(); 950 cvt_fd((float *)&data.v[4], &data.dd); 951 preempt_enable(); 952 #else 953 return 0; 954 #endif 955 break; 956 } 957 958 /* Store result to memory or update registers */ 959 if (flags & ST) { 960 ret = 0; 961 p = (unsigned long) addr; 962 switch (nb) { 963 case 8: 964 ret |= __put_user_inatomic(data.v[0], SWIZ_PTR(p++)); 965 ret |= __put_user_inatomic(data.v[1], SWIZ_PTR(p++)); 966 ret |= __put_user_inatomic(data.v[2], SWIZ_PTR(p++)); 967 ret |= __put_user_inatomic(data.v[3], SWIZ_PTR(p++)); 968 case 4: 969 ret |= __put_user_inatomic(data.v[4], SWIZ_PTR(p++)); 970 ret |= __put_user_inatomic(data.v[5], SWIZ_PTR(p++)); 971 case 2: 972 ret |= __put_user_inatomic(data.v[6], SWIZ_PTR(p++)); 973 ret |= __put_user_inatomic(data.v[7], SWIZ_PTR(p++)); 974 } 975 if (unlikely(ret)) 976 return -EFAULT; 977 } else if (flags & F) 978 current->thread.TS_FPR(reg) = data.dd; 979 else 980 regs->gpr[reg] = data.ll; 981 982 /* Update RA as needed */ 983 if (flags & U) 984 regs->gpr[areg] = regs->dar; 985 986 return 1; 987 } 988