1 /* 2 * cp1emu.c: a MIPS coprocessor 1 (fpu) instruction emulator 3 * 4 * MIPS floating point support 5 * Copyright (C) 1994-2000 Algorithmics Ltd. 6 * 7 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 8 * Copyright (C) 2000 MIPS Technologies, Inc. 9 * 10 * This program is free software; you can distribute it and/or modify it 11 * under the terms of the GNU General Public License (Version 2) as 12 * published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope it will be useful, but WITHOUT 15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 17 * for more details. 18 * 19 * You should have received a copy of the GNU General Public License along 20 * with this program; if not, write to the Free Software Foundation, Inc., 21 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. 22 * 23 * A complete emulator for MIPS coprocessor 1 instructions. This is 24 * required for #float(switch) or #float(trap), where it catches all 25 * COP1 instructions via the "CoProcessor Unusable" exception. 26 * 27 * More surprisingly it is also required for #float(ieee), to help out 28 * the hardware fpu at the boundaries of the IEEE-754 representation 29 * (denormalised values, infinities, underflow, etc). It is made 30 * quite nasty because emulation of some non-COP1 instructions is 31 * required, e.g. in branch delay slots. 32 * 33 * Note if you know that you won't have an fpu, then you'll get much 34 * better performance by compiling with -msoft-float! 35 */ 36 #include <linux/sched.h> 37 #include <linux/module.h> 38 #include <linux/debugfs.h> 39 #include <linux/perf_event.h> 40 41 #include <asm/inst.h> 42 #include <asm/bootinfo.h> 43 #include <asm/processor.h> 44 #include <asm/ptrace.h> 45 #include <asm/signal.h> 46 #include <asm/mipsregs.h> 47 #include <asm/fpu_emulator.h> 48 #include <asm/fpu.h> 49 #include <asm/uaccess.h> 50 #include <asm/branch.h> 51 52 #include "ieee754.h" 53 54 /* Strap kernel emulator for full MIPS IV emulation */ 55 56 #ifdef __mips 57 #undef __mips 58 #endif 59 #define __mips 4 60 61 /* Function which emulates a floating point instruction. */ 62 63 static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *, 64 mips_instruction); 65 66 #if __mips >= 4 && __mips != 32 67 static int fpux_emu(struct pt_regs *, 68 struct mips_fpu_struct *, mips_instruction, void *__user *); 69 #endif 70 71 /* Further private data for which no space exists in mips_fpu_struct */ 72 73 #ifdef CONFIG_DEBUG_FS 74 DEFINE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats); 75 #endif 76 77 /* Control registers */ 78 79 #define FPCREG_RID 0 /* $0 = revision id */ 80 #define FPCREG_CSR 31 /* $31 = csr */ 81 82 /* Determine rounding mode from the RM bits of the FCSR */ 83 #define modeindex(v) ((v) & FPU_CSR_RM) 84 85 /* microMIPS bitfields */ 86 #define MM_POOL32A_MINOR_MASK 0x3f 87 #define MM_POOL32A_MINOR_SHIFT 0x6 88 #define MM_MIPS32_COND_FC 0x30 89 90 /* Convert Mips rounding mode (0..3) to IEEE library modes. */ 91 static const unsigned char ieee_rm[4] = { 92 [FPU_CSR_RN] = IEEE754_RN, 93 [FPU_CSR_RZ] = IEEE754_RZ, 94 [FPU_CSR_RU] = IEEE754_RU, 95 [FPU_CSR_RD] = IEEE754_RD, 96 }; 97 /* Convert IEEE library modes to Mips rounding mode (0..3). */ 98 static const unsigned char mips_rm[4] = { 99 [IEEE754_RN] = FPU_CSR_RN, 100 [IEEE754_RZ] = FPU_CSR_RZ, 101 [IEEE754_RD] = FPU_CSR_RD, 102 [IEEE754_RU] = FPU_CSR_RU, 103 }; 104 105 #if __mips >= 4 106 /* convert condition code register number to csr bit */ 107 static const unsigned int fpucondbit[8] = { 108 FPU_CSR_COND0, 109 FPU_CSR_COND1, 110 FPU_CSR_COND2, 111 FPU_CSR_COND3, 112 FPU_CSR_COND4, 113 FPU_CSR_COND5, 114 FPU_CSR_COND6, 115 FPU_CSR_COND7 116 }; 117 #endif 118 119 /* (microMIPS) Convert 16-bit register encoding to 32-bit register encoding. */ 120 static const unsigned int reg16to32map[8] = {16, 17, 2, 3, 4, 5, 6, 7}; 121 122 /* (microMIPS) Convert certain microMIPS instructions to MIPS32 format. */ 123 static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0}; 124 static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0}; 125 static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0}; 126 static const int swl_format[] = {16, 20, 21, 0, 0, 0, 0, 0}; 127 128 /* 129 * This functions translates a 32-bit microMIPS instruction 130 * into a 32-bit MIPS32 instruction. Returns 0 on success 131 * and SIGILL otherwise. 132 */ 133 static int microMIPS32_to_MIPS32(union mips_instruction *insn_ptr) 134 { 135 union mips_instruction insn = *insn_ptr; 136 union mips_instruction mips32_insn = insn; 137 int func, fmt, op; 138 139 switch (insn.mm_i_format.opcode) { 140 case mm_ldc132_op: 141 mips32_insn.mm_i_format.opcode = ldc1_op; 142 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs; 143 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt; 144 break; 145 case mm_lwc132_op: 146 mips32_insn.mm_i_format.opcode = lwc1_op; 147 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs; 148 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt; 149 break; 150 case mm_sdc132_op: 151 mips32_insn.mm_i_format.opcode = sdc1_op; 152 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs; 153 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt; 154 break; 155 case mm_swc132_op: 156 mips32_insn.mm_i_format.opcode = swc1_op; 157 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs; 158 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt; 159 break; 160 case mm_pool32i_op: 161 /* NOTE: offset is << by 1 if in microMIPS mode. */ 162 if ((insn.mm_i_format.rt == mm_bc1f_op) || 163 (insn.mm_i_format.rt == mm_bc1t_op)) { 164 mips32_insn.fb_format.opcode = cop1_op; 165 mips32_insn.fb_format.bc = bc_op; 166 mips32_insn.fb_format.flag = 167 (insn.mm_i_format.rt == mm_bc1t_op) ? 1 : 0; 168 } else 169 return SIGILL; 170 break; 171 case mm_pool32f_op: 172 switch (insn.mm_fp0_format.func) { 173 case mm_32f_01_op: 174 case mm_32f_11_op: 175 case mm_32f_02_op: 176 case mm_32f_12_op: 177 case mm_32f_41_op: 178 case mm_32f_51_op: 179 case mm_32f_42_op: 180 case mm_32f_52_op: 181 op = insn.mm_fp0_format.func; 182 if (op == mm_32f_01_op) 183 func = madd_s_op; 184 else if (op == mm_32f_11_op) 185 func = madd_d_op; 186 else if (op == mm_32f_02_op) 187 func = nmadd_s_op; 188 else if (op == mm_32f_12_op) 189 func = nmadd_d_op; 190 else if (op == mm_32f_41_op) 191 func = msub_s_op; 192 else if (op == mm_32f_51_op) 193 func = msub_d_op; 194 else if (op == mm_32f_42_op) 195 func = nmsub_s_op; 196 else 197 func = nmsub_d_op; 198 mips32_insn.fp6_format.opcode = cop1x_op; 199 mips32_insn.fp6_format.fr = insn.mm_fp6_format.fr; 200 mips32_insn.fp6_format.ft = insn.mm_fp6_format.ft; 201 mips32_insn.fp6_format.fs = insn.mm_fp6_format.fs; 202 mips32_insn.fp6_format.fd = insn.mm_fp6_format.fd; 203 mips32_insn.fp6_format.func = func; 204 break; 205 case mm_32f_10_op: 206 func = -1; /* Invalid */ 207 op = insn.mm_fp5_format.op & 0x7; 208 if (op == mm_ldxc1_op) 209 func = ldxc1_op; 210 else if (op == mm_sdxc1_op) 211 func = sdxc1_op; 212 else if (op == mm_lwxc1_op) 213 func = lwxc1_op; 214 else if (op == mm_swxc1_op) 215 func = swxc1_op; 216 217 if (func != -1) { 218 mips32_insn.r_format.opcode = cop1x_op; 219 mips32_insn.r_format.rs = 220 insn.mm_fp5_format.base; 221 mips32_insn.r_format.rt = 222 insn.mm_fp5_format.index; 223 mips32_insn.r_format.rd = 0; 224 mips32_insn.r_format.re = insn.mm_fp5_format.fd; 225 mips32_insn.r_format.func = func; 226 } else 227 return SIGILL; 228 break; 229 case mm_32f_40_op: 230 op = -1; /* Invalid */ 231 if (insn.mm_fp2_format.op == mm_fmovt_op) 232 op = 1; 233 else if (insn.mm_fp2_format.op == mm_fmovf_op) 234 op = 0; 235 if (op != -1) { 236 mips32_insn.fp0_format.opcode = cop1_op; 237 mips32_insn.fp0_format.fmt = 238 sdps_format[insn.mm_fp2_format.fmt]; 239 mips32_insn.fp0_format.ft = 240 (insn.mm_fp2_format.cc<<2) + op; 241 mips32_insn.fp0_format.fs = 242 insn.mm_fp2_format.fs; 243 mips32_insn.fp0_format.fd = 244 insn.mm_fp2_format.fd; 245 mips32_insn.fp0_format.func = fmovc_op; 246 } else 247 return SIGILL; 248 break; 249 case mm_32f_60_op: 250 func = -1; /* Invalid */ 251 if (insn.mm_fp0_format.op == mm_fadd_op) 252 func = fadd_op; 253 else if (insn.mm_fp0_format.op == mm_fsub_op) 254 func = fsub_op; 255 else if (insn.mm_fp0_format.op == mm_fmul_op) 256 func = fmul_op; 257 else if (insn.mm_fp0_format.op == mm_fdiv_op) 258 func = fdiv_op; 259 if (func != -1) { 260 mips32_insn.fp0_format.opcode = cop1_op; 261 mips32_insn.fp0_format.fmt = 262 sdps_format[insn.mm_fp0_format.fmt]; 263 mips32_insn.fp0_format.ft = 264 insn.mm_fp0_format.ft; 265 mips32_insn.fp0_format.fs = 266 insn.mm_fp0_format.fs; 267 mips32_insn.fp0_format.fd = 268 insn.mm_fp0_format.fd; 269 mips32_insn.fp0_format.func = func; 270 } else 271 return SIGILL; 272 break; 273 case mm_32f_70_op: 274 func = -1; /* Invalid */ 275 if (insn.mm_fp0_format.op == mm_fmovn_op) 276 func = fmovn_op; 277 else if (insn.mm_fp0_format.op == mm_fmovz_op) 278 func = fmovz_op; 279 if (func != -1) { 280 mips32_insn.fp0_format.opcode = cop1_op; 281 mips32_insn.fp0_format.fmt = 282 sdps_format[insn.mm_fp0_format.fmt]; 283 mips32_insn.fp0_format.ft = 284 insn.mm_fp0_format.ft; 285 mips32_insn.fp0_format.fs = 286 insn.mm_fp0_format.fs; 287 mips32_insn.fp0_format.fd = 288 insn.mm_fp0_format.fd; 289 mips32_insn.fp0_format.func = func; 290 } else 291 return SIGILL; 292 break; 293 case mm_32f_73_op: /* POOL32FXF */ 294 switch (insn.mm_fp1_format.op) { 295 case mm_movf0_op: 296 case mm_movf1_op: 297 case mm_movt0_op: 298 case mm_movt1_op: 299 if ((insn.mm_fp1_format.op & 0x7f) == 300 mm_movf0_op) 301 op = 0; 302 else 303 op = 1; 304 mips32_insn.r_format.opcode = spec_op; 305 mips32_insn.r_format.rs = insn.mm_fp4_format.fs; 306 mips32_insn.r_format.rt = 307 (insn.mm_fp4_format.cc << 2) + op; 308 mips32_insn.r_format.rd = insn.mm_fp4_format.rt; 309 mips32_insn.r_format.re = 0; 310 mips32_insn.r_format.func = movc_op; 311 break; 312 case mm_fcvtd0_op: 313 case mm_fcvtd1_op: 314 case mm_fcvts0_op: 315 case mm_fcvts1_op: 316 if ((insn.mm_fp1_format.op & 0x7f) == 317 mm_fcvtd0_op) { 318 func = fcvtd_op; 319 fmt = swl_format[insn.mm_fp3_format.fmt]; 320 } else { 321 func = fcvts_op; 322 fmt = dwl_format[insn.mm_fp3_format.fmt]; 323 } 324 mips32_insn.fp0_format.opcode = cop1_op; 325 mips32_insn.fp0_format.fmt = fmt; 326 mips32_insn.fp0_format.ft = 0; 327 mips32_insn.fp0_format.fs = 328 insn.mm_fp3_format.fs; 329 mips32_insn.fp0_format.fd = 330 insn.mm_fp3_format.rt; 331 mips32_insn.fp0_format.func = func; 332 break; 333 case mm_fmov0_op: 334 case mm_fmov1_op: 335 case mm_fabs0_op: 336 case mm_fabs1_op: 337 case mm_fneg0_op: 338 case mm_fneg1_op: 339 if ((insn.mm_fp1_format.op & 0x7f) == 340 mm_fmov0_op) 341 func = fmov_op; 342 else if ((insn.mm_fp1_format.op & 0x7f) == 343 mm_fabs0_op) 344 func = fabs_op; 345 else 346 func = fneg_op; 347 mips32_insn.fp0_format.opcode = cop1_op; 348 mips32_insn.fp0_format.fmt = 349 sdps_format[insn.mm_fp3_format.fmt]; 350 mips32_insn.fp0_format.ft = 0; 351 mips32_insn.fp0_format.fs = 352 insn.mm_fp3_format.fs; 353 mips32_insn.fp0_format.fd = 354 insn.mm_fp3_format.rt; 355 mips32_insn.fp0_format.func = func; 356 break; 357 case mm_ffloorl_op: 358 case mm_ffloorw_op: 359 case mm_fceill_op: 360 case mm_fceilw_op: 361 case mm_ftruncl_op: 362 case mm_ftruncw_op: 363 case mm_froundl_op: 364 case mm_froundw_op: 365 case mm_fcvtl_op: 366 case mm_fcvtw_op: 367 if (insn.mm_fp1_format.op == mm_ffloorl_op) 368 func = ffloorl_op; 369 else if (insn.mm_fp1_format.op == mm_ffloorw_op) 370 func = ffloor_op; 371 else if (insn.mm_fp1_format.op == mm_fceill_op) 372 func = fceill_op; 373 else if (insn.mm_fp1_format.op == mm_fceilw_op) 374 func = fceil_op; 375 else if (insn.mm_fp1_format.op == mm_ftruncl_op) 376 func = ftruncl_op; 377 else if (insn.mm_fp1_format.op == mm_ftruncw_op) 378 func = ftrunc_op; 379 else if (insn.mm_fp1_format.op == mm_froundl_op) 380 func = froundl_op; 381 else if (insn.mm_fp1_format.op == mm_froundw_op) 382 func = fround_op; 383 else if (insn.mm_fp1_format.op == mm_fcvtl_op) 384 func = fcvtl_op; 385 else 386 func = fcvtw_op; 387 mips32_insn.fp0_format.opcode = cop1_op; 388 mips32_insn.fp0_format.fmt = 389 sd_format[insn.mm_fp1_format.fmt]; 390 mips32_insn.fp0_format.ft = 0; 391 mips32_insn.fp0_format.fs = 392 insn.mm_fp1_format.fs; 393 mips32_insn.fp0_format.fd = 394 insn.mm_fp1_format.rt; 395 mips32_insn.fp0_format.func = func; 396 break; 397 case mm_frsqrt_op: 398 case mm_fsqrt_op: 399 case mm_frecip_op: 400 if (insn.mm_fp1_format.op == mm_frsqrt_op) 401 func = frsqrt_op; 402 else if (insn.mm_fp1_format.op == mm_fsqrt_op) 403 func = fsqrt_op; 404 else 405 func = frecip_op; 406 mips32_insn.fp0_format.opcode = cop1_op; 407 mips32_insn.fp0_format.fmt = 408 sdps_format[insn.mm_fp1_format.fmt]; 409 mips32_insn.fp0_format.ft = 0; 410 mips32_insn.fp0_format.fs = 411 insn.mm_fp1_format.fs; 412 mips32_insn.fp0_format.fd = 413 insn.mm_fp1_format.rt; 414 mips32_insn.fp0_format.func = func; 415 break; 416 case mm_mfc1_op: 417 case mm_mtc1_op: 418 case mm_cfc1_op: 419 case mm_ctc1_op: 420 if (insn.mm_fp1_format.op == mm_mfc1_op) 421 op = mfc_op; 422 else if (insn.mm_fp1_format.op == mm_mtc1_op) 423 op = mtc_op; 424 else if (insn.mm_fp1_format.op == mm_cfc1_op) 425 op = cfc_op; 426 else 427 op = ctc_op; 428 mips32_insn.fp1_format.opcode = cop1_op; 429 mips32_insn.fp1_format.op = op; 430 mips32_insn.fp1_format.rt = 431 insn.mm_fp1_format.rt; 432 mips32_insn.fp1_format.fs = 433 insn.mm_fp1_format.fs; 434 mips32_insn.fp1_format.fd = 0; 435 mips32_insn.fp1_format.func = 0; 436 break; 437 default: 438 return SIGILL; 439 } 440 break; 441 case mm_32f_74_op: /* c.cond.fmt */ 442 mips32_insn.fp0_format.opcode = cop1_op; 443 mips32_insn.fp0_format.fmt = 444 sdps_format[insn.mm_fp4_format.fmt]; 445 mips32_insn.fp0_format.ft = insn.mm_fp4_format.rt; 446 mips32_insn.fp0_format.fs = insn.mm_fp4_format.fs; 447 mips32_insn.fp0_format.fd = insn.mm_fp4_format.cc << 2; 448 mips32_insn.fp0_format.func = 449 insn.mm_fp4_format.cond | MM_MIPS32_COND_FC; 450 break; 451 default: 452 return SIGILL; 453 } 454 break; 455 default: 456 return SIGILL; 457 } 458 459 *insn_ptr = mips32_insn; 460 return 0; 461 } 462 463 int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, 464 unsigned long *contpc) 465 { 466 union mips_instruction insn = (union mips_instruction)dec_insn.insn; 467 int bc_false = 0; 468 unsigned int fcr31; 469 unsigned int bit; 470 471 if (!cpu_has_mmips) 472 return 0; 473 474 switch (insn.mm_i_format.opcode) { 475 case mm_pool32a_op: 476 if ((insn.mm_i_format.simmediate & MM_POOL32A_MINOR_MASK) == 477 mm_pool32axf_op) { 478 switch (insn.mm_i_format.simmediate >> 479 MM_POOL32A_MINOR_SHIFT) { 480 case mm_jalr_op: 481 case mm_jalrhb_op: 482 case mm_jalrs_op: 483 case mm_jalrshb_op: 484 if (insn.mm_i_format.rt != 0) /* Not mm_jr */ 485 regs->regs[insn.mm_i_format.rt] = 486 regs->cp0_epc + 487 dec_insn.pc_inc + 488 dec_insn.next_pc_inc; 489 *contpc = regs->regs[insn.mm_i_format.rs]; 490 return 1; 491 } 492 } 493 break; 494 case mm_pool32i_op: 495 switch (insn.mm_i_format.rt) { 496 case mm_bltzals_op: 497 case mm_bltzal_op: 498 regs->regs[31] = regs->cp0_epc + 499 dec_insn.pc_inc + 500 dec_insn.next_pc_inc; 501 /* Fall through */ 502 case mm_bltz_op: 503 if ((long)regs->regs[insn.mm_i_format.rs] < 0) 504 *contpc = regs->cp0_epc + 505 dec_insn.pc_inc + 506 (insn.mm_i_format.simmediate << 1); 507 else 508 *contpc = regs->cp0_epc + 509 dec_insn.pc_inc + 510 dec_insn.next_pc_inc; 511 return 1; 512 case mm_bgezals_op: 513 case mm_bgezal_op: 514 regs->regs[31] = regs->cp0_epc + 515 dec_insn.pc_inc + 516 dec_insn.next_pc_inc; 517 /* Fall through */ 518 case mm_bgez_op: 519 if ((long)regs->regs[insn.mm_i_format.rs] >= 0) 520 *contpc = regs->cp0_epc + 521 dec_insn.pc_inc + 522 (insn.mm_i_format.simmediate << 1); 523 else 524 *contpc = regs->cp0_epc + 525 dec_insn.pc_inc + 526 dec_insn.next_pc_inc; 527 return 1; 528 case mm_blez_op: 529 if ((long)regs->regs[insn.mm_i_format.rs] <= 0) 530 *contpc = regs->cp0_epc + 531 dec_insn.pc_inc + 532 (insn.mm_i_format.simmediate << 1); 533 else 534 *contpc = regs->cp0_epc + 535 dec_insn.pc_inc + 536 dec_insn.next_pc_inc; 537 return 1; 538 case mm_bgtz_op: 539 if ((long)regs->regs[insn.mm_i_format.rs] <= 0) 540 *contpc = regs->cp0_epc + 541 dec_insn.pc_inc + 542 (insn.mm_i_format.simmediate << 1); 543 else 544 *contpc = regs->cp0_epc + 545 dec_insn.pc_inc + 546 dec_insn.next_pc_inc; 547 return 1; 548 case mm_bc2f_op: 549 case mm_bc1f_op: 550 bc_false = 1; 551 /* Fall through */ 552 case mm_bc2t_op: 553 case mm_bc1t_op: 554 preempt_disable(); 555 if (is_fpu_owner()) 556 asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); 557 else 558 fcr31 = current->thread.fpu.fcr31; 559 preempt_enable(); 560 561 if (bc_false) 562 fcr31 = ~fcr31; 563 564 bit = (insn.mm_i_format.rs >> 2); 565 bit += (bit != 0); 566 bit += 23; 567 if (fcr31 & (1 << bit)) 568 *contpc = regs->cp0_epc + 569 dec_insn.pc_inc + 570 (insn.mm_i_format.simmediate << 1); 571 else 572 *contpc = regs->cp0_epc + 573 dec_insn.pc_inc + dec_insn.next_pc_inc; 574 return 1; 575 } 576 break; 577 case mm_pool16c_op: 578 switch (insn.mm_i_format.rt) { 579 case mm_jalr16_op: 580 case mm_jalrs16_op: 581 regs->regs[31] = regs->cp0_epc + 582 dec_insn.pc_inc + dec_insn.next_pc_inc; 583 /* Fall through */ 584 case mm_jr16_op: 585 *contpc = regs->regs[insn.mm_i_format.rs]; 586 return 1; 587 } 588 break; 589 case mm_beqz16_op: 590 if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] == 0) 591 *contpc = regs->cp0_epc + 592 dec_insn.pc_inc + 593 (insn.mm_b1_format.simmediate << 1); 594 else 595 *contpc = regs->cp0_epc + 596 dec_insn.pc_inc + dec_insn.next_pc_inc; 597 return 1; 598 case mm_bnez16_op: 599 if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] != 0) 600 *contpc = regs->cp0_epc + 601 dec_insn.pc_inc + 602 (insn.mm_b1_format.simmediate << 1); 603 else 604 *contpc = regs->cp0_epc + 605 dec_insn.pc_inc + dec_insn.next_pc_inc; 606 return 1; 607 case mm_b16_op: 608 *contpc = regs->cp0_epc + dec_insn.pc_inc + 609 (insn.mm_b0_format.simmediate << 1); 610 return 1; 611 case mm_beq32_op: 612 if (regs->regs[insn.mm_i_format.rs] == 613 regs->regs[insn.mm_i_format.rt]) 614 *contpc = regs->cp0_epc + 615 dec_insn.pc_inc + 616 (insn.mm_i_format.simmediate << 1); 617 else 618 *contpc = regs->cp0_epc + 619 dec_insn.pc_inc + 620 dec_insn.next_pc_inc; 621 return 1; 622 case mm_bne32_op: 623 if (regs->regs[insn.mm_i_format.rs] != 624 regs->regs[insn.mm_i_format.rt]) 625 *contpc = regs->cp0_epc + 626 dec_insn.pc_inc + 627 (insn.mm_i_format.simmediate << 1); 628 else 629 *contpc = regs->cp0_epc + 630 dec_insn.pc_inc + dec_insn.next_pc_inc; 631 return 1; 632 case mm_jalx32_op: 633 regs->regs[31] = regs->cp0_epc + 634 dec_insn.pc_inc + dec_insn.next_pc_inc; 635 *contpc = regs->cp0_epc + dec_insn.pc_inc; 636 *contpc >>= 28; 637 *contpc <<= 28; 638 *contpc |= (insn.j_format.target << 2); 639 return 1; 640 case mm_jals32_op: 641 case mm_jal32_op: 642 regs->regs[31] = regs->cp0_epc + 643 dec_insn.pc_inc + dec_insn.next_pc_inc; 644 /* Fall through */ 645 case mm_j32_op: 646 *contpc = regs->cp0_epc + dec_insn.pc_inc; 647 *contpc >>= 27; 648 *contpc <<= 27; 649 *contpc |= (insn.j_format.target << 1); 650 set_isa16_mode(*contpc); 651 return 1; 652 } 653 return 0; 654 } 655 656 /* 657 * Redundant with logic already in kernel/branch.c, 658 * embedded in compute_return_epc. At some point, 659 * a single subroutine should be used across both 660 * modules. 661 */ 662 static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, 663 unsigned long *contpc) 664 { 665 union mips_instruction insn = (union mips_instruction)dec_insn.insn; 666 unsigned int fcr31; 667 unsigned int bit = 0; 668 669 switch (insn.i_format.opcode) { 670 case spec_op: 671 switch (insn.r_format.func) { 672 case jalr_op: 673 regs->regs[insn.r_format.rd] = 674 regs->cp0_epc + dec_insn.pc_inc + 675 dec_insn.next_pc_inc; 676 /* Fall through */ 677 case jr_op: 678 *contpc = regs->regs[insn.r_format.rs]; 679 return 1; 680 } 681 break; 682 case bcond_op: 683 switch (insn.i_format.rt) { 684 case bltzal_op: 685 case bltzall_op: 686 regs->regs[31] = regs->cp0_epc + 687 dec_insn.pc_inc + 688 dec_insn.next_pc_inc; 689 /* Fall through */ 690 case bltz_op: 691 case bltzl_op: 692 if ((long)regs->regs[insn.i_format.rs] < 0) 693 *contpc = regs->cp0_epc + 694 dec_insn.pc_inc + 695 (insn.i_format.simmediate << 2); 696 else 697 *contpc = regs->cp0_epc + 698 dec_insn.pc_inc + 699 dec_insn.next_pc_inc; 700 return 1; 701 case bgezal_op: 702 case bgezall_op: 703 regs->regs[31] = regs->cp0_epc + 704 dec_insn.pc_inc + 705 dec_insn.next_pc_inc; 706 /* Fall through */ 707 case bgez_op: 708 case bgezl_op: 709 if ((long)regs->regs[insn.i_format.rs] >= 0) 710 *contpc = regs->cp0_epc + 711 dec_insn.pc_inc + 712 (insn.i_format.simmediate << 2); 713 else 714 *contpc = regs->cp0_epc + 715 dec_insn.pc_inc + 716 dec_insn.next_pc_inc; 717 return 1; 718 } 719 break; 720 case jalx_op: 721 set_isa16_mode(bit); 722 case jal_op: 723 regs->regs[31] = regs->cp0_epc + 724 dec_insn.pc_inc + 725 dec_insn.next_pc_inc; 726 /* Fall through */ 727 case j_op: 728 *contpc = regs->cp0_epc + dec_insn.pc_inc; 729 *contpc >>= 28; 730 *contpc <<= 28; 731 *contpc |= (insn.j_format.target << 2); 732 /* Set microMIPS mode bit: XOR for jalx. */ 733 *contpc ^= bit; 734 return 1; 735 case beq_op: 736 case beql_op: 737 if (regs->regs[insn.i_format.rs] == 738 regs->regs[insn.i_format.rt]) 739 *contpc = regs->cp0_epc + 740 dec_insn.pc_inc + 741 (insn.i_format.simmediate << 2); 742 else 743 *contpc = regs->cp0_epc + 744 dec_insn.pc_inc + 745 dec_insn.next_pc_inc; 746 return 1; 747 case bne_op: 748 case bnel_op: 749 if (regs->regs[insn.i_format.rs] != 750 regs->regs[insn.i_format.rt]) 751 *contpc = regs->cp0_epc + 752 dec_insn.pc_inc + 753 (insn.i_format.simmediate << 2); 754 else 755 *contpc = regs->cp0_epc + 756 dec_insn.pc_inc + 757 dec_insn.next_pc_inc; 758 return 1; 759 case blez_op: 760 case blezl_op: 761 if ((long)regs->regs[insn.i_format.rs] <= 0) 762 *contpc = regs->cp0_epc + 763 dec_insn.pc_inc + 764 (insn.i_format.simmediate << 2); 765 else 766 *contpc = regs->cp0_epc + 767 dec_insn.pc_inc + 768 dec_insn.next_pc_inc; 769 return 1; 770 case bgtz_op: 771 case bgtzl_op: 772 if ((long)regs->regs[insn.i_format.rs] > 0) 773 *contpc = regs->cp0_epc + 774 dec_insn.pc_inc + 775 (insn.i_format.simmediate << 2); 776 else 777 *contpc = regs->cp0_epc + 778 dec_insn.pc_inc + 779 dec_insn.next_pc_inc; 780 return 1; 781 #ifdef CONFIG_CPU_CAVIUM_OCTEON 782 case lwc2_op: /* This is bbit0 on Octeon */ 783 if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0) 784 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2); 785 else 786 *contpc = regs->cp0_epc + 8; 787 return 1; 788 case ldc2_op: /* This is bbit032 on Octeon */ 789 if ((regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) == 0) 790 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2); 791 else 792 *contpc = regs->cp0_epc + 8; 793 return 1; 794 case swc2_op: /* This is bbit1 on Octeon */ 795 if (regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) 796 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2); 797 else 798 *contpc = regs->cp0_epc + 8; 799 return 1; 800 case sdc2_op: /* This is bbit132 on Octeon */ 801 if (regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) 802 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2); 803 else 804 *contpc = regs->cp0_epc + 8; 805 return 1; 806 #endif 807 case cop0_op: 808 case cop1_op: 809 case cop2_op: 810 case cop1x_op: 811 if (insn.i_format.rs == bc_op) { 812 preempt_disable(); 813 if (is_fpu_owner()) 814 asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); 815 else 816 fcr31 = current->thread.fpu.fcr31; 817 preempt_enable(); 818 819 bit = (insn.i_format.rt >> 2); 820 bit += (bit != 0); 821 bit += 23; 822 switch (insn.i_format.rt & 3) { 823 case 0: /* bc1f */ 824 case 2: /* bc1fl */ 825 if (~fcr31 & (1 << bit)) 826 *contpc = regs->cp0_epc + 827 dec_insn.pc_inc + 828 (insn.i_format.simmediate << 2); 829 else 830 *contpc = regs->cp0_epc + 831 dec_insn.pc_inc + 832 dec_insn.next_pc_inc; 833 return 1; 834 case 1: /* bc1t */ 835 case 3: /* bc1tl */ 836 if (fcr31 & (1 << bit)) 837 *contpc = regs->cp0_epc + 838 dec_insn.pc_inc + 839 (insn.i_format.simmediate << 2); 840 else 841 *contpc = regs->cp0_epc + 842 dec_insn.pc_inc + 843 dec_insn.next_pc_inc; 844 return 1; 845 } 846 } 847 break; 848 } 849 return 0; 850 } 851 852 /* 853 * In the Linux kernel, we support selection of FPR format on the 854 * basis of the Status.FR bit. If an FPU is not present, the FR bit 855 * is hardwired to zero, which would imply a 32-bit FPU even for 856 * 64-bit CPUs so we rather look at TIF_32BIT_REGS. 857 * FPU emu is slow and bulky and optimizing this function offers fairly 858 * sizeable benefits so we try to be clever and make this function return 859 * a constant whenever possible, that is on 64-bit kernels without O32 860 * compatibility enabled and on 32-bit kernels. 861 */ 862 static inline int cop1_64bit(struct pt_regs *xcp) 863 { 864 #if defined(CONFIG_64BIT) && !defined(CONFIG_MIPS32_O32) 865 return 1; 866 #elif defined(CONFIG_64BIT) && defined(CONFIG_MIPS32_O32) 867 return !test_thread_flag(TIF_32BIT_REGS); 868 #else 869 return 0; 870 #endif 871 } 872 873 #define SIFROMREG(si, x) ((si) = cop1_64bit(xcp) || !(x & 1) ? \ 874 (int)ctx->fpr[x] : (int)(ctx->fpr[x & ~1] >> 32)) 875 876 #define SITOREG(si, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = \ 877 cop1_64bit(xcp) || !(x & 1) ? \ 878 ctx->fpr[x & ~1] >> 32 << 32 | (u32)(si) : \ 879 ctx->fpr[x & ~1] << 32 >> 32 | (u64)(si) << 32) 880 881 #define DIFROMREG(di, x) ((di) = ctx->fpr[x & ~(cop1_64bit(xcp) == 0)]) 882 #define DITOREG(di, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = (di)) 883 884 #define SPFROMREG(sp, x) SIFROMREG((sp).bits, x) 885 #define SPTOREG(sp, x) SITOREG((sp).bits, x) 886 #define DPFROMREG(dp, x) DIFROMREG((dp).bits, x) 887 #define DPTOREG(dp, x) DITOREG((dp).bits, x) 888 889 /* 890 * Emulate the single floating point instruction pointed at by EPC. 891 * Two instructions if the instruction is in a branch delay slot. 892 */ 893 894 static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx, 895 struct mm_decoded_insn dec_insn, void *__user *fault_addr) 896 { 897 mips_instruction ir; 898 unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc; 899 unsigned int cond; 900 int pc_inc; 901 902 /* XXX NEC Vr54xx bug workaround */ 903 if (xcp->cp0_cause & CAUSEF_BD) { 904 if (dec_insn.micro_mips_mode) { 905 if (!mm_isBranchInstr(xcp, dec_insn, &contpc)) 906 xcp->cp0_cause &= ~CAUSEF_BD; 907 } else { 908 if (!isBranchInstr(xcp, dec_insn, &contpc)) 909 xcp->cp0_cause &= ~CAUSEF_BD; 910 } 911 } 912 913 if (xcp->cp0_cause & CAUSEF_BD) { 914 /* 915 * The instruction to be emulated is in a branch delay slot 916 * which means that we have to emulate the branch instruction 917 * BEFORE we do the cop1 instruction. 918 * 919 * This branch could be a COP1 branch, but in that case we 920 * would have had a trap for that instruction, and would not 921 * come through this route. 922 * 923 * Linux MIPS branch emulator operates on context, updating the 924 * cp0_epc. 925 */ 926 ir = dec_insn.next_insn; /* process delay slot instr */ 927 pc_inc = dec_insn.next_pc_inc; 928 } else { 929 ir = dec_insn.insn; /* process current instr */ 930 pc_inc = dec_insn.pc_inc; 931 } 932 933 /* 934 * Since microMIPS FPU instructios are a subset of MIPS32 FPU 935 * instructions, we want to convert microMIPS FPU instructions 936 * into MIPS32 instructions so that we could reuse all of the 937 * FPU emulation code. 938 * 939 * NOTE: We cannot do this for branch instructions since they 940 * are not a subset. Example: Cannot emulate a 16-bit 941 * aligned target address with a MIPS32 instruction. 942 */ 943 if (dec_insn.micro_mips_mode) { 944 /* 945 * If next instruction is a 16-bit instruction, then it 946 * it cannot be a FPU instruction. This could happen 947 * since we can be called for non-FPU instructions. 948 */ 949 if ((pc_inc == 2) || 950 (microMIPS32_to_MIPS32((union mips_instruction *)&ir) 951 == SIGILL)) 952 return SIGILL; 953 } 954 955 emul: 956 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0); 957 MIPS_FPU_EMU_INC_STATS(emulated); 958 switch (MIPSInst_OPCODE(ir)) { 959 case ldc1_op:{ 960 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] + 961 MIPSInst_SIMM(ir)); 962 u64 val; 963 964 MIPS_FPU_EMU_INC_STATS(loads); 965 966 if (!access_ok(VERIFY_READ, va, sizeof(u64))) { 967 MIPS_FPU_EMU_INC_STATS(errors); 968 *fault_addr = va; 969 return SIGBUS; 970 } 971 if (__get_user(val, va)) { 972 MIPS_FPU_EMU_INC_STATS(errors); 973 *fault_addr = va; 974 return SIGSEGV; 975 } 976 DITOREG(val, MIPSInst_RT(ir)); 977 break; 978 } 979 980 case sdc1_op:{ 981 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] + 982 MIPSInst_SIMM(ir)); 983 u64 val; 984 985 MIPS_FPU_EMU_INC_STATS(stores); 986 DIFROMREG(val, MIPSInst_RT(ir)); 987 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) { 988 MIPS_FPU_EMU_INC_STATS(errors); 989 *fault_addr = va; 990 return SIGBUS; 991 } 992 if (__put_user(val, va)) { 993 MIPS_FPU_EMU_INC_STATS(errors); 994 *fault_addr = va; 995 return SIGSEGV; 996 } 997 break; 998 } 999 1000 case lwc1_op:{ 1001 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] + 1002 MIPSInst_SIMM(ir)); 1003 u32 val; 1004 1005 MIPS_FPU_EMU_INC_STATS(loads); 1006 if (!access_ok(VERIFY_READ, va, sizeof(u32))) { 1007 MIPS_FPU_EMU_INC_STATS(errors); 1008 *fault_addr = va; 1009 return SIGBUS; 1010 } 1011 if (__get_user(val, va)) { 1012 MIPS_FPU_EMU_INC_STATS(errors); 1013 *fault_addr = va; 1014 return SIGSEGV; 1015 } 1016 SITOREG(val, MIPSInst_RT(ir)); 1017 break; 1018 } 1019 1020 case swc1_op:{ 1021 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] + 1022 MIPSInst_SIMM(ir)); 1023 u32 val; 1024 1025 MIPS_FPU_EMU_INC_STATS(stores); 1026 SIFROMREG(val, MIPSInst_RT(ir)); 1027 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) { 1028 MIPS_FPU_EMU_INC_STATS(errors); 1029 *fault_addr = va; 1030 return SIGBUS; 1031 } 1032 if (__put_user(val, va)) { 1033 MIPS_FPU_EMU_INC_STATS(errors); 1034 *fault_addr = va; 1035 return SIGSEGV; 1036 } 1037 break; 1038 } 1039 1040 case cop1_op: 1041 switch (MIPSInst_RS(ir)) { 1042 1043 #if defined(__mips64) 1044 case dmfc_op: 1045 /* copregister fs -> gpr[rt] */ 1046 if (MIPSInst_RT(ir) != 0) { 1047 DIFROMREG(xcp->regs[MIPSInst_RT(ir)], 1048 MIPSInst_RD(ir)); 1049 } 1050 break; 1051 1052 case dmtc_op: 1053 /* copregister fs <- rt */ 1054 DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir)); 1055 break; 1056 #endif 1057 1058 case mfc_op: 1059 /* copregister rd -> gpr[rt] */ 1060 if (MIPSInst_RT(ir) != 0) { 1061 SIFROMREG(xcp->regs[MIPSInst_RT(ir)], 1062 MIPSInst_RD(ir)); 1063 } 1064 break; 1065 1066 case mtc_op: 1067 /* copregister rd <- rt */ 1068 SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir)); 1069 break; 1070 1071 case cfc_op:{ 1072 /* cop control register rd -> gpr[rt] */ 1073 u32 value; 1074 1075 if (MIPSInst_RD(ir) == FPCREG_CSR) { 1076 value = ctx->fcr31; 1077 value = (value & ~FPU_CSR_RM) | 1078 mips_rm[modeindex(value)]; 1079 #ifdef CSRTRACE 1080 printk("%p gpr[%d]<-csr=%08x\n", 1081 (void *) (xcp->cp0_epc), 1082 MIPSInst_RT(ir), value); 1083 #endif 1084 } 1085 else if (MIPSInst_RD(ir) == FPCREG_RID) 1086 value = 0; 1087 else 1088 value = 0; 1089 if (MIPSInst_RT(ir)) 1090 xcp->regs[MIPSInst_RT(ir)] = value; 1091 break; 1092 } 1093 1094 case ctc_op:{ 1095 /* copregister rd <- rt */ 1096 u32 value; 1097 1098 if (MIPSInst_RT(ir) == 0) 1099 value = 0; 1100 else 1101 value = xcp->regs[MIPSInst_RT(ir)]; 1102 1103 /* we only have one writable control reg 1104 */ 1105 if (MIPSInst_RD(ir) == FPCREG_CSR) { 1106 #ifdef CSRTRACE 1107 printk("%p gpr[%d]->csr=%08x\n", 1108 (void *) (xcp->cp0_epc), 1109 MIPSInst_RT(ir), value); 1110 #endif 1111 1112 /* 1113 * Don't write reserved bits, 1114 * and convert to ieee library modes 1115 */ 1116 ctx->fcr31 = (value & 1117 ~(FPU_CSR_RSVD | FPU_CSR_RM)) | 1118 ieee_rm[modeindex(value)]; 1119 } 1120 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { 1121 return SIGFPE; 1122 } 1123 break; 1124 } 1125 1126 case bc_op:{ 1127 int likely = 0; 1128 1129 if (xcp->cp0_cause & CAUSEF_BD) 1130 return SIGILL; 1131 1132 #if __mips >= 4 1133 cond = ctx->fcr31 & fpucondbit[MIPSInst_RT(ir) >> 2]; 1134 #else 1135 cond = ctx->fcr31 & FPU_CSR_COND; 1136 #endif 1137 switch (MIPSInst_RT(ir) & 3) { 1138 case bcfl_op: 1139 likely = 1; 1140 case bcf_op: 1141 cond = !cond; 1142 break; 1143 case bctl_op: 1144 likely = 1; 1145 case bct_op: 1146 break; 1147 default: 1148 /* thats an illegal instruction */ 1149 return SIGILL; 1150 } 1151 1152 xcp->cp0_cause |= CAUSEF_BD; 1153 if (cond) { 1154 /* branch taken: emulate dslot 1155 * instruction 1156 */ 1157 xcp->cp0_epc += dec_insn.pc_inc; 1158 1159 contpc = MIPSInst_SIMM(ir); 1160 ir = dec_insn.next_insn; 1161 if (dec_insn.micro_mips_mode) { 1162 contpc = (xcp->cp0_epc + (contpc << 1)); 1163 1164 /* If 16-bit instruction, not FPU. */ 1165 if ((dec_insn.next_pc_inc == 2) || 1166 (microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) { 1167 1168 /* 1169 * Since this instruction will 1170 * be put on the stack with 1171 * 32-bit words, get around 1172 * this problem by putting a 1173 * NOP16 as the second one. 1174 */ 1175 if (dec_insn.next_pc_inc == 2) 1176 ir = (ir & (~0xffff)) | MM_NOP16; 1177 1178 /* 1179 * Single step the non-CP1 1180 * instruction in the dslot. 1181 */ 1182 return mips_dsemul(xcp, ir, contpc); 1183 } 1184 } else 1185 contpc = (xcp->cp0_epc + (contpc << 2)); 1186 1187 switch (MIPSInst_OPCODE(ir)) { 1188 case lwc1_op: 1189 case swc1_op: 1190 #if (__mips >= 2 || defined(__mips64)) 1191 case ldc1_op: 1192 case sdc1_op: 1193 #endif 1194 case cop1_op: 1195 #if __mips >= 4 && __mips != 32 1196 case cop1x_op: 1197 #endif 1198 /* its one of ours */ 1199 goto emul; 1200 #if __mips >= 4 1201 case spec_op: 1202 if (MIPSInst_FUNC(ir) == movc_op) 1203 goto emul; 1204 break; 1205 #endif 1206 } 1207 1208 /* 1209 * Single step the non-cp1 1210 * instruction in the dslot 1211 */ 1212 return mips_dsemul(xcp, ir, contpc); 1213 } 1214 else { 1215 /* branch not taken */ 1216 if (likely) { 1217 /* 1218 * branch likely nullifies 1219 * dslot if not taken 1220 */ 1221 xcp->cp0_epc += dec_insn.pc_inc; 1222 contpc += dec_insn.pc_inc; 1223 /* 1224 * else continue & execute 1225 * dslot as normal insn 1226 */ 1227 } 1228 } 1229 break; 1230 } 1231 1232 default: 1233 if (!(MIPSInst_RS(ir) & 0x10)) 1234 return SIGILL; 1235 { 1236 int sig; 1237 1238 /* a real fpu computation instruction */ 1239 if ((sig = fpu_emu(xcp, ctx, ir))) 1240 return sig; 1241 } 1242 } 1243 break; 1244 1245 #if __mips >= 4 && __mips != 32 1246 case cop1x_op:{ 1247 int sig = fpux_emu(xcp, ctx, ir, fault_addr); 1248 if (sig) 1249 return sig; 1250 break; 1251 } 1252 #endif 1253 1254 #if __mips >= 4 1255 case spec_op: 1256 if (MIPSInst_FUNC(ir) != movc_op) 1257 return SIGILL; 1258 cond = fpucondbit[MIPSInst_RT(ir) >> 2]; 1259 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0)) 1260 xcp->regs[MIPSInst_RD(ir)] = 1261 xcp->regs[MIPSInst_RS(ir)]; 1262 break; 1263 #endif 1264 1265 default: 1266 return SIGILL; 1267 } 1268 1269 /* we did it !! */ 1270 xcp->cp0_epc = contpc; 1271 xcp->cp0_cause &= ~CAUSEF_BD; 1272 1273 return 0; 1274 } 1275 1276 /* 1277 * Conversion table from MIPS compare ops 48-63 1278 * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig); 1279 */ 1280 static const unsigned char cmptab[8] = { 1281 0, /* cmp_0 (sig) cmp_sf */ 1282 IEEE754_CUN, /* cmp_un (sig) cmp_ngle */ 1283 IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */ 1284 IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */ 1285 IEEE754_CLT, /* cmp_olt (sig) cmp_lt */ 1286 IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */ 1287 IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */ 1288 IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */ 1289 }; 1290 1291 1292 #if __mips >= 4 && __mips != 32 1293 1294 /* 1295 * Additional MIPS4 instructions 1296 */ 1297 1298 #define DEF3OP(name, p, f1, f2, f3) \ 1299 static ieee754##p fpemu_##p##_##name(ieee754##p r, ieee754##p s, \ 1300 ieee754##p t) \ 1301 { \ 1302 struct _ieee754_csr ieee754_csr_save; \ 1303 s = f1(s, t); \ 1304 ieee754_csr_save = ieee754_csr; \ 1305 s = f2(s, r); \ 1306 ieee754_csr_save.cx |= ieee754_csr.cx; \ 1307 ieee754_csr_save.sx |= ieee754_csr.sx; \ 1308 s = f3(s); \ 1309 ieee754_csr.cx |= ieee754_csr_save.cx; \ 1310 ieee754_csr.sx |= ieee754_csr_save.sx; \ 1311 return s; \ 1312 } 1313 1314 static ieee754dp fpemu_dp_recip(ieee754dp d) 1315 { 1316 return ieee754dp_div(ieee754dp_one(0), d); 1317 } 1318 1319 static ieee754dp fpemu_dp_rsqrt(ieee754dp d) 1320 { 1321 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d)); 1322 } 1323 1324 static ieee754sp fpemu_sp_recip(ieee754sp s) 1325 { 1326 return ieee754sp_div(ieee754sp_one(0), s); 1327 } 1328 1329 static ieee754sp fpemu_sp_rsqrt(ieee754sp s) 1330 { 1331 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s)); 1332 } 1333 1334 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, ); 1335 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, ); 1336 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg); 1337 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg); 1338 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, ); 1339 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, ); 1340 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg); 1341 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg); 1342 1343 static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx, 1344 mips_instruction ir, void *__user *fault_addr) 1345 { 1346 unsigned rcsr = 0; /* resulting csr */ 1347 1348 MIPS_FPU_EMU_INC_STATS(cp1xops); 1349 1350 switch (MIPSInst_FMA_FFMT(ir)) { 1351 case s_fmt:{ /* 0 */ 1352 1353 ieee754sp(*handler) (ieee754sp, ieee754sp, ieee754sp); 1354 ieee754sp fd, fr, fs, ft; 1355 u32 __user *va; 1356 u32 val; 1357 1358 switch (MIPSInst_FUNC(ir)) { 1359 case lwxc1_op: 1360 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] + 1361 xcp->regs[MIPSInst_FT(ir)]); 1362 1363 MIPS_FPU_EMU_INC_STATS(loads); 1364 if (!access_ok(VERIFY_READ, va, sizeof(u32))) { 1365 MIPS_FPU_EMU_INC_STATS(errors); 1366 *fault_addr = va; 1367 return SIGBUS; 1368 } 1369 if (__get_user(val, va)) { 1370 MIPS_FPU_EMU_INC_STATS(errors); 1371 *fault_addr = va; 1372 return SIGSEGV; 1373 } 1374 SITOREG(val, MIPSInst_FD(ir)); 1375 break; 1376 1377 case swxc1_op: 1378 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] + 1379 xcp->regs[MIPSInst_FT(ir)]); 1380 1381 MIPS_FPU_EMU_INC_STATS(stores); 1382 1383 SIFROMREG(val, MIPSInst_FS(ir)); 1384 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) { 1385 MIPS_FPU_EMU_INC_STATS(errors); 1386 *fault_addr = va; 1387 return SIGBUS; 1388 } 1389 if (put_user(val, va)) { 1390 MIPS_FPU_EMU_INC_STATS(errors); 1391 *fault_addr = va; 1392 return SIGSEGV; 1393 } 1394 break; 1395 1396 case madd_s_op: 1397 handler = fpemu_sp_madd; 1398 goto scoptop; 1399 case msub_s_op: 1400 handler = fpemu_sp_msub; 1401 goto scoptop; 1402 case nmadd_s_op: 1403 handler = fpemu_sp_nmadd; 1404 goto scoptop; 1405 case nmsub_s_op: 1406 handler = fpemu_sp_nmsub; 1407 goto scoptop; 1408 1409 scoptop: 1410 SPFROMREG(fr, MIPSInst_FR(ir)); 1411 SPFROMREG(fs, MIPSInst_FS(ir)); 1412 SPFROMREG(ft, MIPSInst_FT(ir)); 1413 fd = (*handler) (fr, fs, ft); 1414 SPTOREG(fd, MIPSInst_FD(ir)); 1415 1416 copcsr: 1417 if (ieee754_cxtest(IEEE754_INEXACT)) 1418 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S; 1419 if (ieee754_cxtest(IEEE754_UNDERFLOW)) 1420 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S; 1421 if (ieee754_cxtest(IEEE754_OVERFLOW)) 1422 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S; 1423 if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) 1424 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S; 1425 1426 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr; 1427 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { 1428 /*printk ("SIGFPE: fpu csr = %08x\n", 1429 ctx->fcr31); */ 1430 return SIGFPE; 1431 } 1432 1433 break; 1434 1435 default: 1436 return SIGILL; 1437 } 1438 break; 1439 } 1440 1441 case d_fmt:{ /* 1 */ 1442 ieee754dp(*handler) (ieee754dp, ieee754dp, ieee754dp); 1443 ieee754dp fd, fr, fs, ft; 1444 u64 __user *va; 1445 u64 val; 1446 1447 switch (MIPSInst_FUNC(ir)) { 1448 case ldxc1_op: 1449 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] + 1450 xcp->regs[MIPSInst_FT(ir)]); 1451 1452 MIPS_FPU_EMU_INC_STATS(loads); 1453 if (!access_ok(VERIFY_READ, va, sizeof(u64))) { 1454 MIPS_FPU_EMU_INC_STATS(errors); 1455 *fault_addr = va; 1456 return SIGBUS; 1457 } 1458 if (__get_user(val, va)) { 1459 MIPS_FPU_EMU_INC_STATS(errors); 1460 *fault_addr = va; 1461 return SIGSEGV; 1462 } 1463 DITOREG(val, MIPSInst_FD(ir)); 1464 break; 1465 1466 case sdxc1_op: 1467 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] + 1468 xcp->regs[MIPSInst_FT(ir)]); 1469 1470 MIPS_FPU_EMU_INC_STATS(stores); 1471 DIFROMREG(val, MIPSInst_FS(ir)); 1472 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) { 1473 MIPS_FPU_EMU_INC_STATS(errors); 1474 *fault_addr = va; 1475 return SIGBUS; 1476 } 1477 if (__put_user(val, va)) { 1478 MIPS_FPU_EMU_INC_STATS(errors); 1479 *fault_addr = va; 1480 return SIGSEGV; 1481 } 1482 break; 1483 1484 case madd_d_op: 1485 handler = fpemu_dp_madd; 1486 goto dcoptop; 1487 case msub_d_op: 1488 handler = fpemu_dp_msub; 1489 goto dcoptop; 1490 case nmadd_d_op: 1491 handler = fpemu_dp_nmadd; 1492 goto dcoptop; 1493 case nmsub_d_op: 1494 handler = fpemu_dp_nmsub; 1495 goto dcoptop; 1496 1497 dcoptop: 1498 DPFROMREG(fr, MIPSInst_FR(ir)); 1499 DPFROMREG(fs, MIPSInst_FS(ir)); 1500 DPFROMREG(ft, MIPSInst_FT(ir)); 1501 fd = (*handler) (fr, fs, ft); 1502 DPTOREG(fd, MIPSInst_FD(ir)); 1503 goto copcsr; 1504 1505 default: 1506 return SIGILL; 1507 } 1508 break; 1509 } 1510 1511 case 0x7: /* 7 */ 1512 if (MIPSInst_FUNC(ir) != pfetch_op) { 1513 return SIGILL; 1514 } 1515 /* ignore prefx operation */ 1516 break; 1517 1518 default: 1519 return SIGILL; 1520 } 1521 1522 return 0; 1523 } 1524 #endif 1525 1526 1527 1528 /* 1529 * Emulate a single COP1 arithmetic instruction. 1530 */ 1531 static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx, 1532 mips_instruction ir) 1533 { 1534 int rfmt; /* resulting format */ 1535 unsigned rcsr = 0; /* resulting csr */ 1536 unsigned cond; 1537 union { 1538 ieee754dp d; 1539 ieee754sp s; 1540 int w; 1541 #ifdef __mips64 1542 s64 l; 1543 #endif 1544 } rv; /* resulting value */ 1545 1546 MIPS_FPU_EMU_INC_STATS(cp1ops); 1547 switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) { 1548 case s_fmt:{ /* 0 */ 1549 union { 1550 ieee754sp(*b) (ieee754sp, ieee754sp); 1551 ieee754sp(*u) (ieee754sp); 1552 } handler; 1553 1554 switch (MIPSInst_FUNC(ir)) { 1555 /* binary ops */ 1556 case fadd_op: 1557 handler.b = ieee754sp_add; 1558 goto scopbop; 1559 case fsub_op: 1560 handler.b = ieee754sp_sub; 1561 goto scopbop; 1562 case fmul_op: 1563 handler.b = ieee754sp_mul; 1564 goto scopbop; 1565 case fdiv_op: 1566 handler.b = ieee754sp_div; 1567 goto scopbop; 1568 1569 /* unary ops */ 1570 #if __mips >= 2 || defined(__mips64) 1571 case fsqrt_op: 1572 handler.u = ieee754sp_sqrt; 1573 goto scopuop; 1574 #endif 1575 #if __mips >= 4 && __mips != 32 1576 case frsqrt_op: 1577 handler.u = fpemu_sp_rsqrt; 1578 goto scopuop; 1579 case frecip_op: 1580 handler.u = fpemu_sp_recip; 1581 goto scopuop; 1582 #endif 1583 #if __mips >= 4 1584 case fmovc_op: 1585 cond = fpucondbit[MIPSInst_FT(ir) >> 2]; 1586 if (((ctx->fcr31 & cond) != 0) != 1587 ((MIPSInst_FT(ir) & 1) != 0)) 1588 return 0; 1589 SPFROMREG(rv.s, MIPSInst_FS(ir)); 1590 break; 1591 case fmovz_op: 1592 if (xcp->regs[MIPSInst_FT(ir)] != 0) 1593 return 0; 1594 SPFROMREG(rv.s, MIPSInst_FS(ir)); 1595 break; 1596 case fmovn_op: 1597 if (xcp->regs[MIPSInst_FT(ir)] == 0) 1598 return 0; 1599 SPFROMREG(rv.s, MIPSInst_FS(ir)); 1600 break; 1601 #endif 1602 case fabs_op: 1603 handler.u = ieee754sp_abs; 1604 goto scopuop; 1605 case fneg_op: 1606 handler.u = ieee754sp_neg; 1607 goto scopuop; 1608 case fmov_op: 1609 /* an easy one */ 1610 SPFROMREG(rv.s, MIPSInst_FS(ir)); 1611 goto copcsr; 1612 1613 /* binary op on handler */ 1614 scopbop: 1615 { 1616 ieee754sp fs, ft; 1617 1618 SPFROMREG(fs, MIPSInst_FS(ir)); 1619 SPFROMREG(ft, MIPSInst_FT(ir)); 1620 1621 rv.s = (*handler.b) (fs, ft); 1622 goto copcsr; 1623 } 1624 scopuop: 1625 { 1626 ieee754sp fs; 1627 1628 SPFROMREG(fs, MIPSInst_FS(ir)); 1629 rv.s = (*handler.u) (fs); 1630 goto copcsr; 1631 } 1632 copcsr: 1633 if (ieee754_cxtest(IEEE754_INEXACT)) 1634 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S; 1635 if (ieee754_cxtest(IEEE754_UNDERFLOW)) 1636 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S; 1637 if (ieee754_cxtest(IEEE754_OVERFLOW)) 1638 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S; 1639 if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) 1640 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S; 1641 if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) 1642 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S; 1643 break; 1644 1645 /* unary conv ops */ 1646 case fcvts_op: 1647 return SIGILL; /* not defined */ 1648 case fcvtd_op:{ 1649 ieee754sp fs; 1650 1651 SPFROMREG(fs, MIPSInst_FS(ir)); 1652 rv.d = ieee754dp_fsp(fs); 1653 rfmt = d_fmt; 1654 goto copcsr; 1655 } 1656 case fcvtw_op:{ 1657 ieee754sp fs; 1658 1659 SPFROMREG(fs, MIPSInst_FS(ir)); 1660 rv.w = ieee754sp_tint(fs); 1661 rfmt = w_fmt; 1662 goto copcsr; 1663 } 1664 1665 #if __mips >= 2 || defined(__mips64) 1666 case fround_op: 1667 case ftrunc_op: 1668 case fceil_op: 1669 case ffloor_op:{ 1670 unsigned int oldrm = ieee754_csr.rm; 1671 ieee754sp fs; 1672 1673 SPFROMREG(fs, MIPSInst_FS(ir)); 1674 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; 1675 rv.w = ieee754sp_tint(fs); 1676 ieee754_csr.rm = oldrm; 1677 rfmt = w_fmt; 1678 goto copcsr; 1679 } 1680 #endif /* __mips >= 2 */ 1681 1682 #if defined(__mips64) 1683 case fcvtl_op:{ 1684 ieee754sp fs; 1685 1686 SPFROMREG(fs, MIPSInst_FS(ir)); 1687 rv.l = ieee754sp_tlong(fs); 1688 rfmt = l_fmt; 1689 goto copcsr; 1690 } 1691 1692 case froundl_op: 1693 case ftruncl_op: 1694 case fceill_op: 1695 case ffloorl_op:{ 1696 unsigned int oldrm = ieee754_csr.rm; 1697 ieee754sp fs; 1698 1699 SPFROMREG(fs, MIPSInst_FS(ir)); 1700 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; 1701 rv.l = ieee754sp_tlong(fs); 1702 ieee754_csr.rm = oldrm; 1703 rfmt = l_fmt; 1704 goto copcsr; 1705 } 1706 #endif /* defined(__mips64) */ 1707 1708 default: 1709 if (MIPSInst_FUNC(ir) >= fcmp_op) { 1710 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op; 1711 ieee754sp fs, ft; 1712 1713 SPFROMREG(fs, MIPSInst_FS(ir)); 1714 SPFROMREG(ft, MIPSInst_FT(ir)); 1715 rv.w = ieee754sp_cmp(fs, ft, 1716 cmptab[cmpop & 0x7], cmpop & 0x8); 1717 rfmt = -1; 1718 if ((cmpop & 0x8) && ieee754_cxtest 1719 (IEEE754_INVALID_OPERATION)) 1720 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S; 1721 else 1722 goto copcsr; 1723 1724 } 1725 else { 1726 return SIGILL; 1727 } 1728 break; 1729 } 1730 break; 1731 } 1732 1733 case d_fmt:{ 1734 union { 1735 ieee754dp(*b) (ieee754dp, ieee754dp); 1736 ieee754dp(*u) (ieee754dp); 1737 } handler; 1738 1739 switch (MIPSInst_FUNC(ir)) { 1740 /* binary ops */ 1741 case fadd_op: 1742 handler.b = ieee754dp_add; 1743 goto dcopbop; 1744 case fsub_op: 1745 handler.b = ieee754dp_sub; 1746 goto dcopbop; 1747 case fmul_op: 1748 handler.b = ieee754dp_mul; 1749 goto dcopbop; 1750 case fdiv_op: 1751 handler.b = ieee754dp_div; 1752 goto dcopbop; 1753 1754 /* unary ops */ 1755 #if __mips >= 2 || defined(__mips64) 1756 case fsqrt_op: 1757 handler.u = ieee754dp_sqrt; 1758 goto dcopuop; 1759 #endif 1760 #if __mips >= 4 && __mips != 32 1761 case frsqrt_op: 1762 handler.u = fpemu_dp_rsqrt; 1763 goto dcopuop; 1764 case frecip_op: 1765 handler.u = fpemu_dp_recip; 1766 goto dcopuop; 1767 #endif 1768 #if __mips >= 4 1769 case fmovc_op: 1770 cond = fpucondbit[MIPSInst_FT(ir) >> 2]; 1771 if (((ctx->fcr31 & cond) != 0) != 1772 ((MIPSInst_FT(ir) & 1) != 0)) 1773 return 0; 1774 DPFROMREG(rv.d, MIPSInst_FS(ir)); 1775 break; 1776 case fmovz_op: 1777 if (xcp->regs[MIPSInst_FT(ir)] != 0) 1778 return 0; 1779 DPFROMREG(rv.d, MIPSInst_FS(ir)); 1780 break; 1781 case fmovn_op: 1782 if (xcp->regs[MIPSInst_FT(ir)] == 0) 1783 return 0; 1784 DPFROMREG(rv.d, MIPSInst_FS(ir)); 1785 break; 1786 #endif 1787 case fabs_op: 1788 handler.u = ieee754dp_abs; 1789 goto dcopuop; 1790 1791 case fneg_op: 1792 handler.u = ieee754dp_neg; 1793 goto dcopuop; 1794 1795 case fmov_op: 1796 /* an easy one */ 1797 DPFROMREG(rv.d, MIPSInst_FS(ir)); 1798 goto copcsr; 1799 1800 /* binary op on handler */ 1801 dcopbop:{ 1802 ieee754dp fs, ft; 1803 1804 DPFROMREG(fs, MIPSInst_FS(ir)); 1805 DPFROMREG(ft, MIPSInst_FT(ir)); 1806 1807 rv.d = (*handler.b) (fs, ft); 1808 goto copcsr; 1809 } 1810 dcopuop:{ 1811 ieee754dp fs; 1812 1813 DPFROMREG(fs, MIPSInst_FS(ir)); 1814 rv.d = (*handler.u) (fs); 1815 goto copcsr; 1816 } 1817 1818 /* unary conv ops */ 1819 case fcvts_op:{ 1820 ieee754dp fs; 1821 1822 DPFROMREG(fs, MIPSInst_FS(ir)); 1823 rv.s = ieee754sp_fdp(fs); 1824 rfmt = s_fmt; 1825 goto copcsr; 1826 } 1827 case fcvtd_op: 1828 return SIGILL; /* not defined */ 1829 1830 case fcvtw_op:{ 1831 ieee754dp fs; 1832 1833 DPFROMREG(fs, MIPSInst_FS(ir)); 1834 rv.w = ieee754dp_tint(fs); /* wrong */ 1835 rfmt = w_fmt; 1836 goto copcsr; 1837 } 1838 1839 #if __mips >= 2 || defined(__mips64) 1840 case fround_op: 1841 case ftrunc_op: 1842 case fceil_op: 1843 case ffloor_op:{ 1844 unsigned int oldrm = ieee754_csr.rm; 1845 ieee754dp fs; 1846 1847 DPFROMREG(fs, MIPSInst_FS(ir)); 1848 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; 1849 rv.w = ieee754dp_tint(fs); 1850 ieee754_csr.rm = oldrm; 1851 rfmt = w_fmt; 1852 goto copcsr; 1853 } 1854 #endif 1855 1856 #if defined(__mips64) 1857 case fcvtl_op:{ 1858 ieee754dp fs; 1859 1860 DPFROMREG(fs, MIPSInst_FS(ir)); 1861 rv.l = ieee754dp_tlong(fs); 1862 rfmt = l_fmt; 1863 goto copcsr; 1864 } 1865 1866 case froundl_op: 1867 case ftruncl_op: 1868 case fceill_op: 1869 case ffloorl_op:{ 1870 unsigned int oldrm = ieee754_csr.rm; 1871 ieee754dp fs; 1872 1873 DPFROMREG(fs, MIPSInst_FS(ir)); 1874 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))]; 1875 rv.l = ieee754dp_tlong(fs); 1876 ieee754_csr.rm = oldrm; 1877 rfmt = l_fmt; 1878 goto copcsr; 1879 } 1880 #endif /* __mips >= 3 */ 1881 1882 default: 1883 if (MIPSInst_FUNC(ir) >= fcmp_op) { 1884 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op; 1885 ieee754dp fs, ft; 1886 1887 DPFROMREG(fs, MIPSInst_FS(ir)); 1888 DPFROMREG(ft, MIPSInst_FT(ir)); 1889 rv.w = ieee754dp_cmp(fs, ft, 1890 cmptab[cmpop & 0x7], cmpop & 0x8); 1891 rfmt = -1; 1892 if ((cmpop & 0x8) 1893 && 1894 ieee754_cxtest 1895 (IEEE754_INVALID_OPERATION)) 1896 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S; 1897 else 1898 goto copcsr; 1899 1900 } 1901 else { 1902 return SIGILL; 1903 } 1904 break; 1905 } 1906 break; 1907 } 1908 1909 case w_fmt:{ 1910 ieee754sp fs; 1911 1912 switch (MIPSInst_FUNC(ir)) { 1913 case fcvts_op: 1914 /* convert word to single precision real */ 1915 SPFROMREG(fs, MIPSInst_FS(ir)); 1916 rv.s = ieee754sp_fint(fs.bits); 1917 rfmt = s_fmt; 1918 goto copcsr; 1919 case fcvtd_op: 1920 /* convert word to double precision real */ 1921 SPFROMREG(fs, MIPSInst_FS(ir)); 1922 rv.d = ieee754dp_fint(fs.bits); 1923 rfmt = d_fmt; 1924 goto copcsr; 1925 default: 1926 return SIGILL; 1927 } 1928 break; 1929 } 1930 1931 #if defined(__mips64) 1932 case l_fmt:{ 1933 switch (MIPSInst_FUNC(ir)) { 1934 case fcvts_op: 1935 /* convert long to single precision real */ 1936 rv.s = ieee754sp_flong(ctx->fpr[MIPSInst_FS(ir)]); 1937 rfmt = s_fmt; 1938 goto copcsr; 1939 case fcvtd_op: 1940 /* convert long to double precision real */ 1941 rv.d = ieee754dp_flong(ctx->fpr[MIPSInst_FS(ir)]); 1942 rfmt = d_fmt; 1943 goto copcsr; 1944 default: 1945 return SIGILL; 1946 } 1947 break; 1948 } 1949 #endif 1950 1951 default: 1952 return SIGILL; 1953 } 1954 1955 /* 1956 * Update the fpu CSR register for this operation. 1957 * If an exception is required, generate a tidy SIGFPE exception, 1958 * without updating the result register. 1959 * Note: cause exception bits do not accumulate, they are rewritten 1960 * for each op; only the flag/sticky bits accumulate. 1961 */ 1962 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr; 1963 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { 1964 /*printk ("SIGFPE: fpu csr = %08x\n",ctx->fcr31); */ 1965 return SIGFPE; 1966 } 1967 1968 /* 1969 * Now we can safely write the result back to the register file. 1970 */ 1971 switch (rfmt) { 1972 case -1:{ 1973 #if __mips >= 4 1974 cond = fpucondbit[MIPSInst_FD(ir) >> 2]; 1975 #else 1976 cond = FPU_CSR_COND; 1977 #endif 1978 if (rv.w) 1979 ctx->fcr31 |= cond; 1980 else 1981 ctx->fcr31 &= ~cond; 1982 break; 1983 } 1984 case d_fmt: 1985 DPTOREG(rv.d, MIPSInst_FD(ir)); 1986 break; 1987 case s_fmt: 1988 SPTOREG(rv.s, MIPSInst_FD(ir)); 1989 break; 1990 case w_fmt: 1991 SITOREG(rv.w, MIPSInst_FD(ir)); 1992 break; 1993 #if defined(__mips64) 1994 case l_fmt: 1995 DITOREG(rv.l, MIPSInst_FD(ir)); 1996 break; 1997 #endif 1998 default: 1999 return SIGILL; 2000 } 2001 2002 return 0; 2003 } 2004 2005 int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, 2006 int has_fpu, void *__user *fault_addr) 2007 { 2008 unsigned long oldepc, prevepc; 2009 struct mm_decoded_insn dec_insn; 2010 u16 instr[4]; 2011 u16 *instr_ptr; 2012 int sig = 0; 2013 2014 oldepc = xcp->cp0_epc; 2015 do { 2016 prevepc = xcp->cp0_epc; 2017 2018 if (get_isa16_mode(prevepc) && cpu_has_mmips) { 2019 /* 2020 * Get next 2 microMIPS instructions and convert them 2021 * into 32-bit instructions. 2022 */ 2023 if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) || 2024 (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) || 2025 (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) || 2026 (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) { 2027 MIPS_FPU_EMU_INC_STATS(errors); 2028 return SIGBUS; 2029 } 2030 instr_ptr = instr; 2031 2032 /* Get first instruction. */ 2033 if (mm_insn_16bit(*instr_ptr)) { 2034 /* Duplicate the half-word. */ 2035 dec_insn.insn = (*instr_ptr << 16) | 2036 (*instr_ptr); 2037 /* 16-bit instruction. */ 2038 dec_insn.pc_inc = 2; 2039 instr_ptr += 1; 2040 } else { 2041 dec_insn.insn = (*instr_ptr << 16) | 2042 *(instr_ptr+1); 2043 /* 32-bit instruction. */ 2044 dec_insn.pc_inc = 4; 2045 instr_ptr += 2; 2046 } 2047 /* Get second instruction. */ 2048 if (mm_insn_16bit(*instr_ptr)) { 2049 /* Duplicate the half-word. */ 2050 dec_insn.next_insn = (*instr_ptr << 16) | 2051 (*instr_ptr); 2052 /* 16-bit instruction. */ 2053 dec_insn.next_pc_inc = 2; 2054 } else { 2055 dec_insn.next_insn = (*instr_ptr << 16) | 2056 *(instr_ptr+1); 2057 /* 32-bit instruction. */ 2058 dec_insn.next_pc_inc = 4; 2059 } 2060 dec_insn.micro_mips_mode = 1; 2061 } else { 2062 if ((get_user(dec_insn.insn, 2063 (mips_instruction __user *) xcp->cp0_epc)) || 2064 (get_user(dec_insn.next_insn, 2065 (mips_instruction __user *)(xcp->cp0_epc+4)))) { 2066 MIPS_FPU_EMU_INC_STATS(errors); 2067 return SIGBUS; 2068 } 2069 dec_insn.pc_inc = 4; 2070 dec_insn.next_pc_inc = 4; 2071 dec_insn.micro_mips_mode = 0; 2072 } 2073 2074 if ((dec_insn.insn == 0) || 2075 ((dec_insn.pc_inc == 2) && 2076 ((dec_insn.insn & 0xffff) == MM_NOP16))) 2077 xcp->cp0_epc += dec_insn.pc_inc; /* Skip NOPs */ 2078 else { 2079 /* 2080 * The 'ieee754_csr' is an alias of 2081 * ctx->fcr31. No need to copy ctx->fcr31 to 2082 * ieee754_csr. But ieee754_csr.rm is ieee 2083 * library modes. (not mips rounding mode) 2084 */ 2085 /* convert to ieee library modes */ 2086 ieee754_csr.rm = ieee_rm[ieee754_csr.rm]; 2087 sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr); 2088 /* revert to mips rounding mode */ 2089 ieee754_csr.rm = mips_rm[ieee754_csr.rm]; 2090 } 2091 2092 if (has_fpu) 2093 break; 2094 if (sig) 2095 break; 2096 2097 cond_resched(); 2098 } while (xcp->cp0_epc > prevepc); 2099 2100 /* SIGILL indicates a non-fpu instruction */ 2101 if (sig == SIGILL && xcp->cp0_epc != oldepc) 2102 /* but if epc has advanced, then ignore it */ 2103 sig = 0; 2104 2105 return sig; 2106 } 2107 2108 #ifdef CONFIG_DEBUG_FS 2109 2110 static int fpuemu_stat_get(void *data, u64 *val) 2111 { 2112 int cpu; 2113 unsigned long sum = 0; 2114 for_each_online_cpu(cpu) { 2115 struct mips_fpu_emulator_stats *ps; 2116 local_t *pv; 2117 ps = &per_cpu(fpuemustats, cpu); 2118 pv = (void *)ps + (unsigned long)data; 2119 sum += local_read(pv); 2120 } 2121 *val = sum; 2122 return 0; 2123 } 2124 DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n"); 2125 2126 extern struct dentry *mips_debugfs_dir; 2127 static int __init debugfs_fpuemu(void) 2128 { 2129 struct dentry *d, *dir; 2130 2131 if (!mips_debugfs_dir) 2132 return -ENODEV; 2133 dir = debugfs_create_dir("fpuemustats", mips_debugfs_dir); 2134 if (!dir) 2135 return -ENOMEM; 2136 2137 #define FPU_STAT_CREATE(M) \ 2138 do { \ 2139 d = debugfs_create_file(#M , S_IRUGO, dir, \ 2140 (void *)offsetof(struct mips_fpu_emulator_stats, M), \ 2141 &fops_fpuemu_stat); \ 2142 if (!d) \ 2143 return -ENOMEM; \ 2144 } while (0) 2145 2146 FPU_STAT_CREATE(emulated); 2147 FPU_STAT_CREATE(loads); 2148 FPU_STAT_CREATE(stores); 2149 FPU_STAT_CREATE(cp1ops); 2150 FPU_STAT_CREATE(cp1xops); 2151 FPU_STAT_CREATE(errors); 2152 2153 return 0; 2154 } 2155 __initcall(debugfs_fpuemu); 2156 #endif 2157