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 * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle 7 * Copyright (C) 1995, 1996 Paul M. Antoine 8 * Copyright (C) 1998 Ulf Carlsson 9 * Copyright (C) 1999 Silicon Graphics, Inc. 10 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 11 * Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki 12 * Copyright (C) 2000, 2001, 2012 MIPS Technologies, Inc. All rights reserved. 13 * Copyright (C) 2014, Imagination Technologies Ltd. 14 */ 15 #include <linux/bitops.h> 16 #include <linux/bug.h> 17 #include <linux/compiler.h> 18 #include <linux/context_tracking.h> 19 #include <linux/cpu_pm.h> 20 #include <linux/kexec.h> 21 #include <linux/init.h> 22 #include <linux/kernel.h> 23 #include <linux/module.h> 24 #include <linux/extable.h> 25 #include <linux/mm.h> 26 #include <linux/sched/mm.h> 27 #include <linux/sched/debug.h> 28 #include <linux/smp.h> 29 #include <linux/spinlock.h> 30 #include <linux/kallsyms.h> 31 #include <linux/memblock.h> 32 #include <linux/interrupt.h> 33 #include <linux/ptrace.h> 34 #include <linux/kgdb.h> 35 #include <linux/kdebug.h> 36 #include <linux/kprobes.h> 37 #include <linux/notifier.h> 38 #include <linux/kdb.h> 39 #include <linux/irq.h> 40 #include <linux/perf_event.h> 41 42 #include <asm/addrspace.h> 43 #include <asm/bootinfo.h> 44 #include <asm/branch.h> 45 #include <asm/break.h> 46 #include <asm/cop2.h> 47 #include <asm/cpu.h> 48 #include <asm/cpu-type.h> 49 #include <asm/dsp.h> 50 #include <asm/fpu.h> 51 #include <asm/fpu_emulator.h> 52 #include <asm/idle.h> 53 #include <asm/isa-rev.h> 54 #include <asm/mips-cps.h> 55 #include <asm/mips-r2-to-r6-emul.h> 56 #include <asm/mipsregs.h> 57 #include <asm/mipsmtregs.h> 58 #include <asm/module.h> 59 #include <asm/msa.h> 60 #include <asm/ptrace.h> 61 #include <asm/regdef.h> 62 #include <asm/sections.h> 63 #include <asm/siginfo.h> 64 #include <asm/tlbdebug.h> 65 #include <asm/traps.h> 66 #include <linux/uaccess.h> 67 #include <asm/watch.h> 68 #include <asm/mmu_context.h> 69 #include <asm/types.h> 70 #include <asm/stacktrace.h> 71 #include <asm/tlbex.h> 72 #include <asm/uasm.h> 73 74 #include <asm/mach-loongson64/cpucfg-emul.h> 75 76 #include "access-helper.h" 77 78 extern void check_wait(void); 79 extern asmlinkage void rollback_handle_int(void); 80 extern asmlinkage void handle_int(void); 81 extern asmlinkage void handle_adel(void); 82 extern asmlinkage void handle_ades(void); 83 extern asmlinkage void handle_ibe(void); 84 extern asmlinkage void handle_dbe(void); 85 extern asmlinkage void handle_sys(void); 86 extern asmlinkage void handle_bp(void); 87 extern asmlinkage void handle_ri(void); 88 extern asmlinkage void handle_ri_rdhwr_tlbp(void); 89 extern asmlinkage void handle_ri_rdhwr(void); 90 extern asmlinkage void handle_cpu(void); 91 extern asmlinkage void handle_ov(void); 92 extern asmlinkage void handle_tr(void); 93 extern asmlinkage void handle_msa_fpe(void); 94 extern asmlinkage void handle_fpe(void); 95 extern asmlinkage void handle_ftlb(void); 96 extern asmlinkage void handle_gsexc(void); 97 extern asmlinkage void handle_msa(void); 98 extern asmlinkage void handle_mdmx(void); 99 extern asmlinkage void handle_watch(void); 100 extern asmlinkage void handle_mt(void); 101 extern asmlinkage void handle_dsp(void); 102 extern asmlinkage void handle_mcheck(void); 103 extern asmlinkage void handle_reserved(void); 104 extern void tlb_do_page_fault_0(void); 105 106 void (*board_be_init)(void); 107 static int (*board_be_handler)(struct pt_regs *regs, int is_fixup); 108 void (*board_nmi_handler_setup)(void); 109 void (*board_ejtag_handler_setup)(void); 110 void (*board_bind_eic_interrupt)(int irq, int regset); 111 void (*board_ebase_setup)(void); 112 void(*board_cache_error_setup)(void); 113 114 void mips_set_be_handler(int (*handler)(struct pt_regs *regs, int is_fixup)) 115 { 116 board_be_handler = handler; 117 } 118 EXPORT_SYMBOL_GPL(mips_set_be_handler); 119 120 static void show_raw_backtrace(unsigned long reg29, const char *loglvl, 121 bool user) 122 { 123 unsigned long *sp = (unsigned long *)(reg29 & ~3); 124 unsigned long addr; 125 126 printk("%sCall Trace:", loglvl); 127 #ifdef CONFIG_KALLSYMS 128 printk("%s\n", loglvl); 129 #endif 130 while (!kstack_end(sp)) { 131 if (__get_addr(&addr, sp++, user)) { 132 printk("%s (Bad stack address)", loglvl); 133 break; 134 } 135 if (__kernel_text_address(addr)) 136 print_ip_sym(loglvl, addr); 137 } 138 printk("%s\n", loglvl); 139 } 140 141 #ifdef CONFIG_KALLSYMS 142 int raw_show_trace; 143 static int __init set_raw_show_trace(char *str) 144 { 145 raw_show_trace = 1; 146 return 1; 147 } 148 __setup("raw_show_trace", set_raw_show_trace); 149 #endif 150 151 static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, 152 const char *loglvl, bool user) 153 { 154 unsigned long sp = regs->regs[29]; 155 unsigned long ra = regs->regs[31]; 156 unsigned long pc = regs->cp0_epc; 157 158 if (!task) 159 task = current; 160 161 if (raw_show_trace || user_mode(regs) || !__kernel_text_address(pc)) { 162 show_raw_backtrace(sp, loglvl, user); 163 return; 164 } 165 printk("%sCall Trace:\n", loglvl); 166 do { 167 print_ip_sym(loglvl, pc); 168 pc = unwind_stack(task, &sp, pc, &ra); 169 } while (pc); 170 pr_cont("\n"); 171 } 172 173 /* 174 * This routine abuses get_user()/put_user() to reference pointers 175 * with at least a bit of error checking ... 176 */ 177 static void show_stacktrace(struct task_struct *task, 178 const struct pt_regs *regs, const char *loglvl, bool user) 179 { 180 const int field = 2 * sizeof(unsigned long); 181 unsigned long stackdata; 182 int i; 183 unsigned long *sp = (unsigned long *)regs->regs[29]; 184 185 printk("%sStack :", loglvl); 186 i = 0; 187 while ((unsigned long) sp & (PAGE_SIZE - 1)) { 188 if (i && ((i % (64 / field)) == 0)) { 189 pr_cont("\n"); 190 printk("%s ", loglvl); 191 } 192 if (i > 39) { 193 pr_cont(" ..."); 194 break; 195 } 196 197 if (__get_addr(&stackdata, sp++, user)) { 198 pr_cont(" (Bad stack address)"); 199 break; 200 } 201 202 pr_cont(" %0*lx", field, stackdata); 203 i++; 204 } 205 pr_cont("\n"); 206 show_backtrace(task, regs, loglvl, user); 207 } 208 209 void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl) 210 { 211 struct pt_regs regs; 212 213 regs.cp0_status = KSU_KERNEL; 214 if (sp) { 215 regs.regs[29] = (unsigned long)sp; 216 regs.regs[31] = 0; 217 regs.cp0_epc = 0; 218 } else { 219 if (task && task != current) { 220 regs.regs[29] = task->thread.reg29; 221 regs.regs[31] = 0; 222 regs.cp0_epc = task->thread.reg31; 223 } else { 224 prepare_frametrace(®s); 225 } 226 } 227 show_stacktrace(task, ®s, loglvl, false); 228 } 229 230 static void show_code(void *pc, bool user) 231 { 232 long i; 233 unsigned short *pc16 = NULL; 234 235 printk("Code:"); 236 237 if ((unsigned long)pc & 1) 238 pc16 = (u16 *)((unsigned long)pc & ~1); 239 240 for(i = -3 ; i < 6 ; i++) { 241 if (pc16) { 242 u16 insn16; 243 244 if (__get_inst16(&insn16, pc16 + i, user)) 245 goto bad_address; 246 247 pr_cont("%c%04x%c", (i?' ':'<'), insn16, (i?' ':'>')); 248 } else { 249 u32 insn32; 250 251 if (__get_inst32(&insn32, (u32 *)pc + i, user)) 252 goto bad_address; 253 254 pr_cont("%c%08x%c", (i?' ':'<'), insn32, (i?' ':'>')); 255 } 256 } 257 pr_cont("\n"); 258 return; 259 260 bad_address: 261 pr_cont(" (Bad address in epc)\n\n"); 262 } 263 264 static void __show_regs(const struct pt_regs *regs) 265 { 266 const int field = 2 * sizeof(unsigned long); 267 unsigned int cause = regs->cp0_cause; 268 unsigned int exccode; 269 int i; 270 271 show_regs_print_info(KERN_DEFAULT); 272 273 /* 274 * Saved main processor registers 275 */ 276 for (i = 0; i < 32; ) { 277 if ((i % 4) == 0) 278 printk("$%2d :", i); 279 if (i == 0) 280 pr_cont(" %0*lx", field, 0UL); 281 else if (i == 26 || i == 27) 282 pr_cont(" %*s", field, ""); 283 else 284 pr_cont(" %0*lx", field, regs->regs[i]); 285 286 i++; 287 if ((i % 4) == 0) 288 pr_cont("\n"); 289 } 290 291 #ifdef CONFIG_CPU_HAS_SMARTMIPS 292 printk("Acx : %0*lx\n", field, regs->acx); 293 #endif 294 if (MIPS_ISA_REV < 6) { 295 printk("Hi : %0*lx\n", field, regs->hi); 296 printk("Lo : %0*lx\n", field, regs->lo); 297 } 298 299 /* 300 * Saved cp0 registers 301 */ 302 printk("epc : %0*lx %pS\n", field, regs->cp0_epc, 303 (void *) regs->cp0_epc); 304 printk("ra : %0*lx %pS\n", field, regs->regs[31], 305 (void *) regs->regs[31]); 306 307 printk("Status: %08x ", (uint32_t) regs->cp0_status); 308 309 if (cpu_has_3kex) { 310 if (regs->cp0_status & ST0_KUO) 311 pr_cont("KUo "); 312 if (regs->cp0_status & ST0_IEO) 313 pr_cont("IEo "); 314 if (regs->cp0_status & ST0_KUP) 315 pr_cont("KUp "); 316 if (regs->cp0_status & ST0_IEP) 317 pr_cont("IEp "); 318 if (regs->cp0_status & ST0_KUC) 319 pr_cont("KUc "); 320 if (regs->cp0_status & ST0_IEC) 321 pr_cont("IEc "); 322 } else if (cpu_has_4kex) { 323 if (regs->cp0_status & ST0_KX) 324 pr_cont("KX "); 325 if (regs->cp0_status & ST0_SX) 326 pr_cont("SX "); 327 if (regs->cp0_status & ST0_UX) 328 pr_cont("UX "); 329 switch (regs->cp0_status & ST0_KSU) { 330 case KSU_USER: 331 pr_cont("USER "); 332 break; 333 case KSU_SUPERVISOR: 334 pr_cont("SUPERVISOR "); 335 break; 336 case KSU_KERNEL: 337 pr_cont("KERNEL "); 338 break; 339 default: 340 pr_cont("BAD_MODE "); 341 break; 342 } 343 if (regs->cp0_status & ST0_ERL) 344 pr_cont("ERL "); 345 if (regs->cp0_status & ST0_EXL) 346 pr_cont("EXL "); 347 if (regs->cp0_status & ST0_IE) 348 pr_cont("IE "); 349 } 350 pr_cont("\n"); 351 352 exccode = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE; 353 printk("Cause : %08x (ExcCode %02x)\n", cause, exccode); 354 355 if (1 <= exccode && exccode <= 5) 356 printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr); 357 358 printk("PrId : %08x (%s)\n", read_c0_prid(), 359 cpu_name_string()); 360 } 361 362 /* 363 * FIXME: really the generic show_regs should take a const pointer argument. 364 */ 365 void show_regs(struct pt_regs *regs) 366 { 367 __show_regs(regs); 368 dump_stack(); 369 } 370 371 void show_registers(struct pt_regs *regs) 372 { 373 const int field = 2 * sizeof(unsigned long); 374 375 __show_regs(regs); 376 print_modules(); 377 printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n", 378 current->comm, current->pid, current_thread_info(), current, 379 field, current_thread_info()->tp_value); 380 if (cpu_has_userlocal) { 381 unsigned long tls; 382 383 tls = read_c0_userlocal(); 384 if (tls != current_thread_info()->tp_value) 385 printk("*HwTLS: %0*lx\n", field, tls); 386 } 387 388 show_stacktrace(current, regs, KERN_DEFAULT, user_mode(regs)); 389 show_code((void *)regs->cp0_epc, user_mode(regs)); 390 printk("\n"); 391 } 392 393 static DEFINE_RAW_SPINLOCK(die_lock); 394 395 void __noreturn die(const char *str, struct pt_regs *regs) 396 { 397 static int die_counter; 398 int sig = SIGSEGV; 399 400 oops_enter(); 401 402 if (notify_die(DIE_OOPS, str, regs, 0, current->thread.trap_nr, 403 SIGSEGV) == NOTIFY_STOP) 404 sig = 0; 405 406 console_verbose(); 407 raw_spin_lock_irq(&die_lock); 408 bust_spinlocks(1); 409 410 printk("%s[#%d]:\n", str, ++die_counter); 411 show_registers(regs); 412 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); 413 raw_spin_unlock_irq(&die_lock); 414 415 oops_exit(); 416 417 if (in_interrupt()) 418 panic("Fatal exception in interrupt"); 419 420 if (panic_on_oops) 421 panic("Fatal exception"); 422 423 if (regs && kexec_should_crash(current)) 424 crash_kexec(regs); 425 426 make_task_dead(sig); 427 } 428 429 extern struct exception_table_entry __start___dbe_table[]; 430 extern struct exception_table_entry __stop___dbe_table[]; 431 432 __asm__( 433 " .section __dbe_table, \"a\"\n" 434 " .previous \n"); 435 436 /* Given an address, look for it in the exception tables. */ 437 static const struct exception_table_entry *search_dbe_tables(unsigned long addr) 438 { 439 const struct exception_table_entry *e; 440 441 e = search_extable(__start___dbe_table, 442 __stop___dbe_table - __start___dbe_table, addr); 443 if (!e) 444 e = search_module_dbetables(addr); 445 return e; 446 } 447 448 asmlinkage void do_be(struct pt_regs *regs) 449 { 450 const int field = 2 * sizeof(unsigned long); 451 const struct exception_table_entry *fixup = NULL; 452 int data = regs->cp0_cause & 4; 453 int action = MIPS_BE_FATAL; 454 enum ctx_state prev_state; 455 456 prev_state = exception_enter(); 457 /* XXX For now. Fixme, this searches the wrong table ... */ 458 if (data && !user_mode(regs)) 459 fixup = search_dbe_tables(exception_epc(regs)); 460 461 if (fixup) 462 action = MIPS_BE_FIXUP; 463 464 if (board_be_handler) 465 action = board_be_handler(regs, fixup != NULL); 466 else 467 mips_cm_error_report(); 468 469 switch (action) { 470 case MIPS_BE_DISCARD: 471 goto out; 472 case MIPS_BE_FIXUP: 473 if (fixup) { 474 regs->cp0_epc = fixup->nextinsn; 475 goto out; 476 } 477 break; 478 default: 479 break; 480 } 481 482 /* 483 * Assume it would be too dangerous to continue ... 484 */ 485 printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n", 486 data ? "Data" : "Instruction", 487 field, regs->cp0_epc, field, regs->regs[31]); 488 if (notify_die(DIE_OOPS, "bus error", regs, 0, current->thread.trap_nr, 489 SIGBUS) == NOTIFY_STOP) 490 goto out; 491 492 die_if_kernel("Oops", regs); 493 force_sig(SIGBUS); 494 495 out: 496 exception_exit(prev_state); 497 } 498 499 /* 500 * ll/sc, rdhwr, sync emulation 501 */ 502 503 #define OPCODE 0xfc000000 504 #define BASE 0x03e00000 505 #define RT 0x001f0000 506 #define OFFSET 0x0000ffff 507 #define LL 0xc0000000 508 #define SC 0xe0000000 509 #define SPEC0 0x00000000 510 #define SPEC3 0x7c000000 511 #define RD 0x0000f800 512 #define FUNC 0x0000003f 513 #define SYNC 0x0000000f 514 #define RDHWR 0x0000003b 515 516 /* microMIPS definitions */ 517 #define MM_POOL32A_FUNC 0xfc00ffff 518 #define MM_RDHWR 0x00006b3c 519 #define MM_RS 0x001f0000 520 #define MM_RT 0x03e00000 521 522 /* 523 * The ll_bit is cleared by r*_switch.S 524 */ 525 526 unsigned int ll_bit; 527 struct task_struct *ll_task; 528 529 static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode) 530 { 531 unsigned long value, __user *vaddr; 532 long offset; 533 534 /* 535 * analyse the ll instruction that just caused a ri exception 536 * and put the referenced address to addr. 537 */ 538 539 /* sign extend offset */ 540 offset = opcode & OFFSET; 541 offset <<= 16; 542 offset >>= 16; 543 544 vaddr = (unsigned long __user *) 545 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset); 546 547 if ((unsigned long)vaddr & 3) 548 return SIGBUS; 549 if (get_user(value, vaddr)) 550 return SIGSEGV; 551 552 preempt_disable(); 553 554 if (ll_task == NULL || ll_task == current) { 555 ll_bit = 1; 556 } else { 557 ll_bit = 0; 558 } 559 ll_task = current; 560 561 preempt_enable(); 562 563 regs->regs[(opcode & RT) >> 16] = value; 564 565 return 0; 566 } 567 568 static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode) 569 { 570 unsigned long __user *vaddr; 571 unsigned long reg; 572 long offset; 573 574 /* 575 * analyse the sc instruction that just caused a ri exception 576 * and put the referenced address to addr. 577 */ 578 579 /* sign extend offset */ 580 offset = opcode & OFFSET; 581 offset <<= 16; 582 offset >>= 16; 583 584 vaddr = (unsigned long __user *) 585 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset); 586 reg = (opcode & RT) >> 16; 587 588 if ((unsigned long)vaddr & 3) 589 return SIGBUS; 590 591 preempt_disable(); 592 593 if (ll_bit == 0 || ll_task != current) { 594 regs->regs[reg] = 0; 595 preempt_enable(); 596 return 0; 597 } 598 599 preempt_enable(); 600 601 if (put_user(regs->regs[reg], vaddr)) 602 return SIGSEGV; 603 604 regs->regs[reg] = 1; 605 606 return 0; 607 } 608 609 /* 610 * ll uses the opcode of lwc0 and sc uses the opcode of swc0. That is both 611 * opcodes are supposed to result in coprocessor unusable exceptions if 612 * executed on ll/sc-less processors. That's the theory. In practice a 613 * few processors such as NEC's VR4100 throw reserved instruction exceptions 614 * instead, so we're doing the emulation thing in both exception handlers. 615 */ 616 static int simulate_llsc(struct pt_regs *regs, unsigned int opcode) 617 { 618 if ((opcode & OPCODE) == LL) { 619 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 620 1, regs, 0); 621 return simulate_ll(regs, opcode); 622 } 623 if ((opcode & OPCODE) == SC) { 624 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 625 1, regs, 0); 626 return simulate_sc(regs, opcode); 627 } 628 629 return -1; /* Must be something else ... */ 630 } 631 632 /* 633 * Simulate trapping 'rdhwr' instructions to provide user accessible 634 * registers not implemented in hardware. 635 */ 636 static int simulate_rdhwr(struct pt_regs *regs, int rd, int rt) 637 { 638 struct thread_info *ti = task_thread_info(current); 639 640 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 641 1, regs, 0); 642 switch (rd) { 643 case MIPS_HWR_CPUNUM: /* CPU number */ 644 regs->regs[rt] = smp_processor_id(); 645 return 0; 646 case MIPS_HWR_SYNCISTEP: /* SYNCI length */ 647 regs->regs[rt] = min(current_cpu_data.dcache.linesz, 648 current_cpu_data.icache.linesz); 649 return 0; 650 case MIPS_HWR_CC: /* Read count register */ 651 regs->regs[rt] = read_c0_count(); 652 return 0; 653 case MIPS_HWR_CCRES: /* Count register resolution */ 654 switch (current_cpu_type()) { 655 case CPU_20KC: 656 case CPU_25KF: 657 regs->regs[rt] = 1; 658 break; 659 default: 660 regs->regs[rt] = 2; 661 } 662 return 0; 663 case MIPS_HWR_ULR: /* Read UserLocal register */ 664 regs->regs[rt] = ti->tp_value; 665 return 0; 666 default: 667 return -1; 668 } 669 } 670 671 static int simulate_rdhwr_normal(struct pt_regs *regs, unsigned int opcode) 672 { 673 if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) { 674 int rd = (opcode & RD) >> 11; 675 int rt = (opcode & RT) >> 16; 676 677 simulate_rdhwr(regs, rd, rt); 678 return 0; 679 } 680 681 /* Not ours. */ 682 return -1; 683 } 684 685 static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned int opcode) 686 { 687 if ((opcode & MM_POOL32A_FUNC) == MM_RDHWR) { 688 int rd = (opcode & MM_RS) >> 16; 689 int rt = (opcode & MM_RT) >> 21; 690 simulate_rdhwr(regs, rd, rt); 691 return 0; 692 } 693 694 /* Not ours. */ 695 return -1; 696 } 697 698 static int simulate_sync(struct pt_regs *regs, unsigned int opcode) 699 { 700 if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) { 701 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 702 1, regs, 0); 703 return 0; 704 } 705 706 return -1; /* Must be something else ... */ 707 } 708 709 /* 710 * Loongson-3 CSR instructions emulation 711 */ 712 713 #ifdef CONFIG_CPU_LOONGSON3_CPUCFG_EMULATION 714 715 #define LWC2 0xc8000000 716 #define RS BASE 717 #define CSR_OPCODE2 0x00000118 718 #define CSR_OPCODE2_MASK 0x000007ff 719 #define CSR_FUNC_MASK RT 720 #define CSR_FUNC_CPUCFG 0x8 721 722 static int simulate_loongson3_cpucfg(struct pt_regs *regs, 723 unsigned int opcode) 724 { 725 int op = opcode & OPCODE; 726 int op2 = opcode & CSR_OPCODE2_MASK; 727 int csr_func = (opcode & CSR_FUNC_MASK) >> 16; 728 729 if (op == LWC2 && op2 == CSR_OPCODE2 && csr_func == CSR_FUNC_CPUCFG) { 730 int rd = (opcode & RD) >> 11; 731 int rs = (opcode & RS) >> 21; 732 __u64 sel = regs->regs[rs]; 733 734 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); 735 736 /* Do not emulate on unsupported core models. */ 737 preempt_disable(); 738 if (!loongson3_cpucfg_emulation_enabled(¤t_cpu_data)) { 739 preempt_enable(); 740 return -1; 741 } 742 regs->regs[rd] = loongson3_cpucfg_read_synthesized( 743 ¤t_cpu_data, sel); 744 preempt_enable(); 745 return 0; 746 } 747 748 /* Not ours. */ 749 return -1; 750 } 751 #endif /* CONFIG_CPU_LOONGSON3_CPUCFG_EMULATION */ 752 753 asmlinkage void do_ov(struct pt_regs *regs) 754 { 755 enum ctx_state prev_state; 756 757 prev_state = exception_enter(); 758 die_if_kernel("Integer overflow", regs); 759 760 force_sig_fault(SIGFPE, FPE_INTOVF, (void __user *)regs->cp0_epc); 761 exception_exit(prev_state); 762 } 763 764 #ifdef CONFIG_MIPS_FP_SUPPORT 765 766 /* 767 * Send SIGFPE according to FCSR Cause bits, which must have already 768 * been masked against Enable bits. This is impotant as Inexact can 769 * happen together with Overflow or Underflow, and `ptrace' can set 770 * any bits. 771 */ 772 void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr, 773 struct task_struct *tsk) 774 { 775 int si_code = FPE_FLTUNK; 776 777 if (fcr31 & FPU_CSR_INV_X) 778 si_code = FPE_FLTINV; 779 else if (fcr31 & FPU_CSR_DIV_X) 780 si_code = FPE_FLTDIV; 781 else if (fcr31 & FPU_CSR_OVF_X) 782 si_code = FPE_FLTOVF; 783 else if (fcr31 & FPU_CSR_UDF_X) 784 si_code = FPE_FLTUND; 785 else if (fcr31 & FPU_CSR_INE_X) 786 si_code = FPE_FLTRES; 787 788 force_sig_fault_to_task(SIGFPE, si_code, fault_addr, tsk); 789 } 790 791 int process_fpemu_return(int sig, void __user *fault_addr, unsigned long fcr31) 792 { 793 int si_code; 794 795 switch (sig) { 796 case 0: 797 return 0; 798 799 case SIGFPE: 800 force_fcr31_sig(fcr31, fault_addr, current); 801 return 1; 802 803 case SIGBUS: 804 force_sig_fault(SIGBUS, BUS_ADRERR, fault_addr); 805 return 1; 806 807 case SIGSEGV: 808 mmap_read_lock(current->mm); 809 if (vma_lookup(current->mm, (unsigned long)fault_addr)) 810 si_code = SEGV_ACCERR; 811 else 812 si_code = SEGV_MAPERR; 813 mmap_read_unlock(current->mm); 814 force_sig_fault(SIGSEGV, si_code, fault_addr); 815 return 1; 816 817 default: 818 force_sig(sig); 819 return 1; 820 } 821 } 822 823 static int simulate_fp(struct pt_regs *regs, unsigned int opcode, 824 unsigned long old_epc, unsigned long old_ra) 825 { 826 union mips_instruction inst = { .word = opcode }; 827 void __user *fault_addr; 828 unsigned long fcr31; 829 int sig; 830 831 /* If it's obviously not an FP instruction, skip it */ 832 switch (inst.i_format.opcode) { 833 case cop1_op: 834 case cop1x_op: 835 case lwc1_op: 836 case ldc1_op: 837 case swc1_op: 838 case sdc1_op: 839 break; 840 841 default: 842 return -1; 843 } 844 845 /* 846 * do_ri skipped over the instruction via compute_return_epc, undo 847 * that for the FPU emulator. 848 */ 849 regs->cp0_epc = old_epc; 850 regs->regs[31] = old_ra; 851 852 /* Run the emulator */ 853 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, 854 &fault_addr); 855 856 /* 857 * We can't allow the emulated instruction to leave any 858 * enabled Cause bits set in $fcr31. 859 */ 860 fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); 861 current->thread.fpu.fcr31 &= ~fcr31; 862 863 /* Restore the hardware register state */ 864 own_fpu(1); 865 866 /* Send a signal if required. */ 867 process_fpemu_return(sig, fault_addr, fcr31); 868 869 return 0; 870 } 871 872 /* 873 * XXX Delayed fp exceptions when doing a lazy ctx switch XXX 874 */ 875 asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) 876 { 877 enum ctx_state prev_state; 878 void __user *fault_addr; 879 int sig; 880 881 prev_state = exception_enter(); 882 if (notify_die(DIE_FP, "FP exception", regs, 0, current->thread.trap_nr, 883 SIGFPE) == NOTIFY_STOP) 884 goto out; 885 886 /* Clear FCSR.Cause before enabling interrupts */ 887 write_32bit_cp1_register(CP1_STATUS, fcr31 & ~mask_fcr31_x(fcr31)); 888 local_irq_enable(); 889 890 die_if_kernel("FP exception in kernel code", regs); 891 892 if (fcr31 & FPU_CSR_UNI_X) { 893 /* 894 * Unimplemented operation exception. If we've got the full 895 * software emulator on-board, let's use it... 896 * 897 * Force FPU to dump state into task/thread context. We're 898 * moving a lot of data here for what is probably a single 899 * instruction, but the alternative is to pre-decode the FP 900 * register operands before invoking the emulator, which seems 901 * a bit extreme for what should be an infrequent event. 902 */ 903 904 /* Run the emulator */ 905 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, 906 &fault_addr); 907 908 /* 909 * We can't allow the emulated instruction to leave any 910 * enabled Cause bits set in $fcr31. 911 */ 912 fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); 913 current->thread.fpu.fcr31 &= ~fcr31; 914 915 /* Restore the hardware register state */ 916 own_fpu(1); /* Using the FPU again. */ 917 } else { 918 sig = SIGFPE; 919 fault_addr = (void __user *) regs->cp0_epc; 920 } 921 922 /* Send a signal if required. */ 923 process_fpemu_return(sig, fault_addr, fcr31); 924 925 out: 926 exception_exit(prev_state); 927 } 928 929 /* 930 * MIPS MT processors may have fewer FPU contexts than CPU threads. If we've 931 * emulated more than some threshold number of instructions, force migration to 932 * a "CPU" that has FP support. 933 */ 934 static void mt_ase_fp_affinity(void) 935 { 936 #ifdef CONFIG_MIPS_MT_FPAFF 937 if (mt_fpemul_threshold > 0 && 938 ((current->thread.emulated_fp++ > mt_fpemul_threshold))) { 939 /* 940 * If there's no FPU present, or if the application has already 941 * restricted the allowed set to exclude any CPUs with FPUs, 942 * we'll skip the procedure. 943 */ 944 if (cpumask_intersects(¤t->cpus_mask, &mt_fpu_cpumask)) { 945 cpumask_t tmask; 946 947 current->thread.user_cpus_allowed 948 = current->cpus_mask; 949 cpumask_and(&tmask, ¤t->cpus_mask, 950 &mt_fpu_cpumask); 951 set_cpus_allowed_ptr(current, &tmask); 952 set_thread_flag(TIF_FPUBOUND); 953 } 954 } 955 #endif /* CONFIG_MIPS_MT_FPAFF */ 956 } 957 958 #else /* !CONFIG_MIPS_FP_SUPPORT */ 959 960 static int simulate_fp(struct pt_regs *regs, unsigned int opcode, 961 unsigned long old_epc, unsigned long old_ra) 962 { 963 return -1; 964 } 965 966 #endif /* !CONFIG_MIPS_FP_SUPPORT */ 967 968 void do_trap_or_bp(struct pt_regs *regs, unsigned int code, int si_code, 969 const char *str) 970 { 971 char b[40]; 972 973 #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP 974 if (kgdb_ll_trap(DIE_TRAP, str, regs, code, current->thread.trap_nr, 975 SIGTRAP) == NOTIFY_STOP) 976 return; 977 #endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */ 978 979 if (notify_die(DIE_TRAP, str, regs, code, current->thread.trap_nr, 980 SIGTRAP) == NOTIFY_STOP) 981 return; 982 983 /* 984 * A short test says that IRIX 5.3 sends SIGTRAP for all trap 985 * insns, even for trap and break codes that indicate arithmetic 986 * failures. Weird ... 987 * But should we continue the brokenness??? --macro 988 */ 989 switch (code) { 990 case BRK_OVERFLOW: 991 case BRK_DIVZERO: 992 scnprintf(b, sizeof(b), "%s instruction in kernel code", str); 993 die_if_kernel(b, regs); 994 force_sig_fault(SIGFPE, 995 code == BRK_DIVZERO ? FPE_INTDIV : FPE_INTOVF, 996 (void __user *) regs->cp0_epc); 997 break; 998 case BRK_BUG: 999 die_if_kernel("Kernel bug detected", regs); 1000 force_sig(SIGTRAP); 1001 break; 1002 case BRK_MEMU: 1003 /* 1004 * This breakpoint code is used by the FPU emulator to retake 1005 * control of the CPU after executing the instruction from the 1006 * delay slot of an emulated branch. 1007 * 1008 * Terminate if exception was recognized as a delay slot return 1009 * otherwise handle as normal. 1010 */ 1011 if (do_dsemulret(regs)) 1012 return; 1013 1014 die_if_kernel("Math emu break/trap", regs); 1015 force_sig(SIGTRAP); 1016 break; 1017 default: 1018 scnprintf(b, sizeof(b), "%s instruction in kernel code", str); 1019 die_if_kernel(b, regs); 1020 if (si_code) { 1021 force_sig_fault(SIGTRAP, si_code, NULL); 1022 } else { 1023 force_sig(SIGTRAP); 1024 } 1025 } 1026 } 1027 1028 asmlinkage void do_bp(struct pt_regs *regs) 1029 { 1030 unsigned long epc = msk_isa16_mode(exception_epc(regs)); 1031 unsigned int opcode, bcode; 1032 enum ctx_state prev_state; 1033 bool user = user_mode(regs); 1034 1035 prev_state = exception_enter(); 1036 current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; 1037 if (get_isa16_mode(regs->cp0_epc)) { 1038 u16 instr[2]; 1039 1040 if (__get_inst16(&instr[0], (u16 *)epc, user)) 1041 goto out_sigsegv; 1042 1043 if (!cpu_has_mmips) { 1044 /* MIPS16e mode */ 1045 bcode = (instr[0] >> 5) & 0x3f; 1046 } else if (mm_insn_16bit(instr[0])) { 1047 /* 16-bit microMIPS BREAK */ 1048 bcode = instr[0] & 0xf; 1049 } else { 1050 /* 32-bit microMIPS BREAK */ 1051 if (__get_inst16(&instr[1], (u16 *)(epc + 2), user)) 1052 goto out_sigsegv; 1053 opcode = (instr[0] << 16) | instr[1]; 1054 bcode = (opcode >> 6) & ((1 << 20) - 1); 1055 } 1056 } else { 1057 if (__get_inst32(&opcode, (u32 *)epc, user)) 1058 goto out_sigsegv; 1059 bcode = (opcode >> 6) & ((1 << 20) - 1); 1060 } 1061 1062 /* 1063 * There is the ancient bug in the MIPS assemblers that the break 1064 * code starts left to bit 16 instead to bit 6 in the opcode. 1065 * Gas is bug-compatible, but not always, grrr... 1066 * We handle both cases with a simple heuristics. --macro 1067 */ 1068 if (bcode >= (1 << 10)) 1069 bcode = ((bcode & ((1 << 10) - 1)) << 10) | (bcode >> 10); 1070 1071 /* 1072 * notify the kprobe handlers, if instruction is likely to 1073 * pertain to them. 1074 */ 1075 switch (bcode) { 1076 case BRK_UPROBE: 1077 if (notify_die(DIE_UPROBE, "uprobe", regs, bcode, 1078 current->thread.trap_nr, SIGTRAP) == NOTIFY_STOP) 1079 goto out; 1080 else 1081 break; 1082 case BRK_UPROBE_XOL: 1083 if (notify_die(DIE_UPROBE_XOL, "uprobe_xol", regs, bcode, 1084 current->thread.trap_nr, SIGTRAP) == NOTIFY_STOP) 1085 goto out; 1086 else 1087 break; 1088 case BRK_KPROBE_BP: 1089 if (notify_die(DIE_BREAK, "debug", regs, bcode, 1090 current->thread.trap_nr, SIGTRAP) == NOTIFY_STOP) 1091 goto out; 1092 else 1093 break; 1094 case BRK_KPROBE_SSTEPBP: 1095 if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, 1096 current->thread.trap_nr, SIGTRAP) == NOTIFY_STOP) 1097 goto out; 1098 else 1099 break; 1100 default: 1101 break; 1102 } 1103 1104 do_trap_or_bp(regs, bcode, TRAP_BRKPT, "Break"); 1105 1106 out: 1107 exception_exit(prev_state); 1108 return; 1109 1110 out_sigsegv: 1111 force_sig(SIGSEGV); 1112 goto out; 1113 } 1114 1115 asmlinkage void do_tr(struct pt_regs *regs) 1116 { 1117 u32 opcode, tcode = 0; 1118 enum ctx_state prev_state; 1119 u16 instr[2]; 1120 bool user = user_mode(regs); 1121 unsigned long epc = msk_isa16_mode(exception_epc(regs)); 1122 1123 prev_state = exception_enter(); 1124 current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; 1125 if (get_isa16_mode(regs->cp0_epc)) { 1126 if (__get_inst16(&instr[0], (u16 *)(epc + 0), user) || 1127 __get_inst16(&instr[1], (u16 *)(epc + 2), user)) 1128 goto out_sigsegv; 1129 opcode = (instr[0] << 16) | instr[1]; 1130 /* Immediate versions don't provide a code. */ 1131 if (!(opcode & OPCODE)) 1132 tcode = (opcode >> 12) & ((1 << 4) - 1); 1133 } else { 1134 if (__get_inst32(&opcode, (u32 *)epc, user)) 1135 goto out_sigsegv; 1136 /* Immediate versions don't provide a code. */ 1137 if (!(opcode & OPCODE)) 1138 tcode = (opcode >> 6) & ((1 << 10) - 1); 1139 } 1140 1141 do_trap_or_bp(regs, tcode, 0, "Trap"); 1142 1143 out: 1144 exception_exit(prev_state); 1145 return; 1146 1147 out_sigsegv: 1148 force_sig(SIGSEGV); 1149 goto out; 1150 } 1151 1152 asmlinkage void do_ri(struct pt_regs *regs) 1153 { 1154 unsigned int __user *epc = (unsigned int __user *)exception_epc(regs); 1155 unsigned long old_epc = regs->cp0_epc; 1156 unsigned long old31 = regs->regs[31]; 1157 enum ctx_state prev_state; 1158 unsigned int opcode = 0; 1159 int status = -1; 1160 1161 /* 1162 * Avoid any kernel code. Just emulate the R2 instruction 1163 * as quickly as possible. 1164 */ 1165 if (mipsr2_emulation && cpu_has_mips_r6 && 1166 likely(user_mode(regs)) && 1167 likely(get_user(opcode, epc) >= 0)) { 1168 unsigned long fcr31 = 0; 1169 1170 status = mipsr2_decoder(regs, opcode, &fcr31); 1171 switch (status) { 1172 case 0: 1173 case SIGEMT: 1174 return; 1175 case SIGILL: 1176 goto no_r2_instr; 1177 default: 1178 process_fpemu_return(status, 1179 ¤t->thread.cp0_baduaddr, 1180 fcr31); 1181 return; 1182 } 1183 } 1184 1185 no_r2_instr: 1186 1187 prev_state = exception_enter(); 1188 current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; 1189 1190 if (notify_die(DIE_RI, "RI Fault", regs, 0, current->thread.trap_nr, 1191 SIGILL) == NOTIFY_STOP) 1192 goto out; 1193 1194 die_if_kernel("Reserved instruction in kernel code", regs); 1195 1196 if (unlikely(compute_return_epc(regs) < 0)) 1197 goto out; 1198 1199 if (!get_isa16_mode(regs->cp0_epc)) { 1200 if (unlikely(get_user(opcode, epc) < 0)) 1201 status = SIGSEGV; 1202 1203 if (!cpu_has_llsc && status < 0) 1204 status = simulate_llsc(regs, opcode); 1205 1206 if (status < 0) 1207 status = simulate_rdhwr_normal(regs, opcode); 1208 1209 if (status < 0) 1210 status = simulate_sync(regs, opcode); 1211 1212 if (status < 0) 1213 status = simulate_fp(regs, opcode, old_epc, old31); 1214 1215 #ifdef CONFIG_CPU_LOONGSON3_CPUCFG_EMULATION 1216 if (status < 0) 1217 status = simulate_loongson3_cpucfg(regs, opcode); 1218 #endif 1219 } else if (cpu_has_mmips) { 1220 unsigned short mmop[2] = { 0 }; 1221 1222 if (unlikely(get_user(mmop[0], (u16 __user *)epc + 0) < 0)) 1223 status = SIGSEGV; 1224 if (unlikely(get_user(mmop[1], (u16 __user *)epc + 1) < 0)) 1225 status = SIGSEGV; 1226 opcode = mmop[0]; 1227 opcode = (opcode << 16) | mmop[1]; 1228 1229 if (status < 0) 1230 status = simulate_rdhwr_mm(regs, opcode); 1231 } 1232 1233 if (status < 0) 1234 status = SIGILL; 1235 1236 if (unlikely(status > 0)) { 1237 regs->cp0_epc = old_epc; /* Undo skip-over. */ 1238 regs->regs[31] = old31; 1239 force_sig(status); 1240 } 1241 1242 out: 1243 exception_exit(prev_state); 1244 } 1245 1246 /* 1247 * No lock; only written during early bootup by CPU 0. 1248 */ 1249 static RAW_NOTIFIER_HEAD(cu2_chain); 1250 1251 int __ref register_cu2_notifier(struct notifier_block *nb) 1252 { 1253 return raw_notifier_chain_register(&cu2_chain, nb); 1254 } 1255 1256 int cu2_notifier_call_chain(unsigned long val, void *v) 1257 { 1258 return raw_notifier_call_chain(&cu2_chain, val, v); 1259 } 1260 1261 static int default_cu2_call(struct notifier_block *nfb, unsigned long action, 1262 void *data) 1263 { 1264 struct pt_regs *regs = data; 1265 1266 die_if_kernel("COP2: Unhandled kernel unaligned access or invalid " 1267 "instruction", regs); 1268 force_sig(SIGILL); 1269 1270 return NOTIFY_OK; 1271 } 1272 1273 #ifdef CONFIG_MIPS_FP_SUPPORT 1274 1275 static int enable_restore_fp_context(int msa) 1276 { 1277 int err, was_fpu_owner, prior_msa; 1278 bool first_fp; 1279 1280 /* Initialize context if it hasn't been used already */ 1281 first_fp = init_fp_ctx(current); 1282 1283 if (first_fp) { 1284 preempt_disable(); 1285 err = own_fpu_inatomic(1); 1286 if (msa && !err) { 1287 enable_msa(); 1288 /* 1289 * with MSA enabled, userspace can see MSACSR 1290 * and MSA regs, but the values in them are from 1291 * other task before current task, restore them 1292 * from saved fp/msa context 1293 */ 1294 write_msa_csr(current->thread.fpu.msacsr); 1295 /* 1296 * own_fpu_inatomic(1) just restore low 64bit, 1297 * fix the high 64bit 1298 */ 1299 init_msa_upper(); 1300 set_thread_flag(TIF_USEDMSA); 1301 set_thread_flag(TIF_MSA_CTX_LIVE); 1302 } 1303 preempt_enable(); 1304 return err; 1305 } 1306 1307 /* 1308 * This task has formerly used the FP context. 1309 * 1310 * If this thread has no live MSA vector context then we can simply 1311 * restore the scalar FP context. If it has live MSA vector context 1312 * (that is, it has or may have used MSA since last performing a 1313 * function call) then we'll need to restore the vector context. This 1314 * applies even if we're currently only executing a scalar FP 1315 * instruction. This is because if we were to later execute an MSA 1316 * instruction then we'd either have to: 1317 * 1318 * - Restore the vector context & clobber any registers modified by 1319 * scalar FP instructions between now & then. 1320 * 1321 * or 1322 * 1323 * - Not restore the vector context & lose the most significant bits 1324 * of all vector registers. 1325 * 1326 * Neither of those options is acceptable. We cannot restore the least 1327 * significant bits of the registers now & only restore the most 1328 * significant bits later because the most significant bits of any 1329 * vector registers whose aliased FP register is modified now will have 1330 * been zeroed. We'd have no way to know that when restoring the vector 1331 * context & thus may load an outdated value for the most significant 1332 * bits of a vector register. 1333 */ 1334 if (!msa && !thread_msa_context_live()) 1335 return own_fpu(1); 1336 1337 /* 1338 * This task is using or has previously used MSA. Thus we require 1339 * that Status.FR == 1. 1340 */ 1341 preempt_disable(); 1342 was_fpu_owner = is_fpu_owner(); 1343 err = own_fpu_inatomic(0); 1344 if (err) 1345 goto out; 1346 1347 enable_msa(); 1348 write_msa_csr(current->thread.fpu.msacsr); 1349 set_thread_flag(TIF_USEDMSA); 1350 1351 /* 1352 * If this is the first time that the task is using MSA and it has 1353 * previously used scalar FP in this time slice then we already nave 1354 * FP context which we shouldn't clobber. We do however need to clear 1355 * the upper 64b of each vector register so that this task has no 1356 * opportunity to see data left behind by another. 1357 */ 1358 prior_msa = test_and_set_thread_flag(TIF_MSA_CTX_LIVE); 1359 if (!prior_msa && was_fpu_owner) { 1360 init_msa_upper(); 1361 1362 goto out; 1363 } 1364 1365 if (!prior_msa) { 1366 /* 1367 * Restore the least significant 64b of each vector register 1368 * from the existing scalar FP context. 1369 */ 1370 _restore_fp(current); 1371 1372 /* 1373 * The task has not formerly used MSA, so clear the upper 64b 1374 * of each vector register such that it cannot see data left 1375 * behind by another task. 1376 */ 1377 init_msa_upper(); 1378 } else { 1379 /* We need to restore the vector context. */ 1380 restore_msa(current); 1381 1382 /* Restore the scalar FP control & status register */ 1383 if (!was_fpu_owner) 1384 write_32bit_cp1_register(CP1_STATUS, 1385 current->thread.fpu.fcr31); 1386 } 1387 1388 out: 1389 preempt_enable(); 1390 1391 return 0; 1392 } 1393 1394 #else /* !CONFIG_MIPS_FP_SUPPORT */ 1395 1396 static int enable_restore_fp_context(int msa) 1397 { 1398 return SIGILL; 1399 } 1400 1401 #endif /* CONFIG_MIPS_FP_SUPPORT */ 1402 1403 asmlinkage void do_cpu(struct pt_regs *regs) 1404 { 1405 enum ctx_state prev_state; 1406 unsigned int __user *epc; 1407 unsigned long old_epc, old31; 1408 unsigned int opcode; 1409 unsigned int cpid; 1410 int status; 1411 1412 prev_state = exception_enter(); 1413 cpid = (regs->cp0_cause >> CAUSEB_CE) & 3; 1414 1415 if (cpid != 2) 1416 die_if_kernel("do_cpu invoked from kernel context!", regs); 1417 1418 switch (cpid) { 1419 case 0: 1420 epc = (unsigned int __user *)exception_epc(regs); 1421 old_epc = regs->cp0_epc; 1422 old31 = regs->regs[31]; 1423 opcode = 0; 1424 status = -1; 1425 1426 if (unlikely(compute_return_epc(regs) < 0)) 1427 break; 1428 1429 if (!get_isa16_mode(regs->cp0_epc)) { 1430 if (unlikely(get_user(opcode, epc) < 0)) 1431 status = SIGSEGV; 1432 1433 if (!cpu_has_llsc && status < 0) 1434 status = simulate_llsc(regs, opcode); 1435 } 1436 1437 if (status < 0) 1438 status = SIGILL; 1439 1440 if (unlikely(status > 0)) { 1441 regs->cp0_epc = old_epc; /* Undo skip-over. */ 1442 regs->regs[31] = old31; 1443 force_sig(status); 1444 } 1445 1446 break; 1447 1448 #ifdef CONFIG_MIPS_FP_SUPPORT 1449 case 3: 1450 /* 1451 * The COP3 opcode space and consequently the CP0.Status.CU3 1452 * bit and the CP0.Cause.CE=3 encoding have been removed as 1453 * of the MIPS III ISA. From the MIPS IV and MIPS32r2 ISAs 1454 * up the space has been reused for COP1X instructions, that 1455 * are enabled by the CP0.Status.CU1 bit and consequently 1456 * use the CP0.Cause.CE=1 encoding for Coprocessor Unusable 1457 * exceptions. Some FPU-less processors that implement one 1458 * of these ISAs however use this code erroneously for COP1X 1459 * instructions. Therefore we redirect this trap to the FP 1460 * emulator too. 1461 */ 1462 if (raw_cpu_has_fpu || !cpu_has_mips_4_5_64_r2_r6) { 1463 force_sig(SIGILL); 1464 break; 1465 } 1466 fallthrough; 1467 case 1: { 1468 void __user *fault_addr; 1469 unsigned long fcr31; 1470 int err, sig; 1471 1472 err = enable_restore_fp_context(0); 1473 1474 if (raw_cpu_has_fpu && !err) 1475 break; 1476 1477 sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 0, 1478 &fault_addr); 1479 1480 /* 1481 * We can't allow the emulated instruction to leave 1482 * any enabled Cause bits set in $fcr31. 1483 */ 1484 fcr31 = mask_fcr31_x(current->thread.fpu.fcr31); 1485 current->thread.fpu.fcr31 &= ~fcr31; 1486 1487 /* Send a signal if required. */ 1488 if (!process_fpemu_return(sig, fault_addr, fcr31) && !err) 1489 mt_ase_fp_affinity(); 1490 1491 break; 1492 } 1493 #else /* CONFIG_MIPS_FP_SUPPORT */ 1494 case 1: 1495 case 3: 1496 force_sig(SIGILL); 1497 break; 1498 #endif /* CONFIG_MIPS_FP_SUPPORT */ 1499 1500 case 2: 1501 raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs); 1502 break; 1503 } 1504 1505 exception_exit(prev_state); 1506 } 1507 1508 asmlinkage void do_msa_fpe(struct pt_regs *regs, unsigned int msacsr) 1509 { 1510 enum ctx_state prev_state; 1511 1512 prev_state = exception_enter(); 1513 current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f; 1514 if (notify_die(DIE_MSAFP, "MSA FP exception", regs, 0, 1515 current->thread.trap_nr, SIGFPE) == NOTIFY_STOP) 1516 goto out; 1517 1518 /* Clear MSACSR.Cause before enabling interrupts */ 1519 write_msa_csr(msacsr & ~MSA_CSR_CAUSEF); 1520 local_irq_enable(); 1521 1522 die_if_kernel("do_msa_fpe invoked from kernel context!", regs); 1523 force_sig(SIGFPE); 1524 out: 1525 exception_exit(prev_state); 1526 } 1527 1528 asmlinkage void do_msa(struct pt_regs *regs) 1529 { 1530 enum ctx_state prev_state; 1531 int err; 1532 1533 prev_state = exception_enter(); 1534 1535 if (!cpu_has_msa || test_thread_flag(TIF_32BIT_FPREGS)) { 1536 force_sig(SIGILL); 1537 goto out; 1538 } 1539 1540 die_if_kernel("do_msa invoked from kernel context!", regs); 1541 1542 err = enable_restore_fp_context(1); 1543 if (err) 1544 force_sig(SIGILL); 1545 out: 1546 exception_exit(prev_state); 1547 } 1548 1549 asmlinkage void do_mdmx(struct pt_regs *regs) 1550 { 1551 enum ctx_state prev_state; 1552 1553 prev_state = exception_enter(); 1554 force_sig(SIGILL); 1555 exception_exit(prev_state); 1556 } 1557 1558 /* 1559 * Called with interrupts disabled. 1560 */ 1561 asmlinkage void do_watch(struct pt_regs *regs) 1562 { 1563 enum ctx_state prev_state; 1564 1565 prev_state = exception_enter(); 1566 /* 1567 * Clear WP (bit 22) bit of cause register so we don't loop 1568 * forever. 1569 */ 1570 clear_c0_cause(CAUSEF_WP); 1571 1572 /* 1573 * If the current thread has the watch registers loaded, save 1574 * their values and send SIGTRAP. Otherwise another thread 1575 * left the registers set, clear them and continue. 1576 */ 1577 if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) { 1578 mips_read_watch_registers(); 1579 local_irq_enable(); 1580 force_sig_fault(SIGTRAP, TRAP_HWBKPT, NULL); 1581 } else { 1582 mips_clear_watch_registers(); 1583 local_irq_enable(); 1584 } 1585 exception_exit(prev_state); 1586 } 1587 1588 asmlinkage void do_mcheck(struct pt_regs *regs) 1589 { 1590 int multi_match = regs->cp0_status & ST0_TS; 1591 enum ctx_state prev_state; 1592 1593 prev_state = exception_enter(); 1594 show_regs(regs); 1595 1596 if (multi_match) { 1597 dump_tlb_regs(); 1598 pr_info("\n"); 1599 dump_tlb_all(); 1600 } 1601 1602 show_code((void *)regs->cp0_epc, user_mode(regs)); 1603 1604 /* 1605 * Some chips may have other causes of machine check (e.g. SB1 1606 * graduation timer) 1607 */ 1608 panic("Caught Machine Check exception - %scaused by multiple " 1609 "matching entries in the TLB.", 1610 (multi_match) ? "" : "not "); 1611 } 1612 1613 asmlinkage void do_mt(struct pt_regs *regs) 1614 { 1615 int subcode; 1616 1617 subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT) 1618 >> VPECONTROL_EXCPT_SHIFT; 1619 switch (subcode) { 1620 case 0: 1621 printk(KERN_DEBUG "Thread Underflow\n"); 1622 break; 1623 case 1: 1624 printk(KERN_DEBUG "Thread Overflow\n"); 1625 break; 1626 case 2: 1627 printk(KERN_DEBUG "Invalid YIELD Qualifier\n"); 1628 break; 1629 case 3: 1630 printk(KERN_DEBUG "Gating Storage Exception\n"); 1631 break; 1632 case 4: 1633 printk(KERN_DEBUG "YIELD Scheduler Exception\n"); 1634 break; 1635 case 5: 1636 printk(KERN_DEBUG "Gating Storage Scheduler Exception\n"); 1637 break; 1638 default: 1639 printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n", 1640 subcode); 1641 break; 1642 } 1643 die_if_kernel("MIPS MT Thread exception in kernel", regs); 1644 1645 force_sig(SIGILL); 1646 } 1647 1648 1649 asmlinkage void do_dsp(struct pt_regs *regs) 1650 { 1651 if (cpu_has_dsp) 1652 panic("Unexpected DSP exception"); 1653 1654 force_sig(SIGILL); 1655 } 1656 1657 asmlinkage void do_reserved(struct pt_regs *regs) 1658 { 1659 /* 1660 * Game over - no way to handle this if it ever occurs. Most probably 1661 * caused by a new unknown cpu type or after another deadly 1662 * hard/software error. 1663 */ 1664 show_regs(regs); 1665 panic("Caught reserved exception %ld - should not happen.", 1666 (regs->cp0_cause & 0x7f) >> 2); 1667 } 1668 1669 static int __initdata l1parity = 1; 1670 static int __init nol1parity(char *s) 1671 { 1672 l1parity = 0; 1673 return 1; 1674 } 1675 __setup("nol1par", nol1parity); 1676 static int __initdata l2parity = 1; 1677 static int __init nol2parity(char *s) 1678 { 1679 l2parity = 0; 1680 return 1; 1681 } 1682 __setup("nol2par", nol2parity); 1683 1684 /* 1685 * Some MIPS CPUs can enable/disable for cache parity detection, but do 1686 * it different ways. 1687 */ 1688 static inline __init void parity_protection_init(void) 1689 { 1690 #define ERRCTL_PE 0x80000000 1691 #define ERRCTL_L2P 0x00800000 1692 1693 if (mips_cm_revision() >= CM_REV_CM3) { 1694 ulong gcr_ectl, cp0_ectl; 1695 1696 /* 1697 * With CM3 systems we need to ensure that the L1 & L2 1698 * parity enables are set to the same value, since this 1699 * is presumed by the hardware engineers. 1700 * 1701 * If the user disabled either of L1 or L2 ECC checking, 1702 * disable both. 1703 */ 1704 l1parity &= l2parity; 1705 l2parity &= l1parity; 1706 1707 /* Probe L1 ECC support */ 1708 cp0_ectl = read_c0_ecc(); 1709 write_c0_ecc(cp0_ectl | ERRCTL_PE); 1710 back_to_back_c0_hazard(); 1711 cp0_ectl = read_c0_ecc(); 1712 1713 /* Probe L2 ECC support */ 1714 gcr_ectl = read_gcr_err_control(); 1715 1716 if (!(gcr_ectl & CM_GCR_ERR_CONTROL_L2_ECC_SUPPORT) || 1717 !(cp0_ectl & ERRCTL_PE)) { 1718 /* 1719 * One of L1 or L2 ECC checking isn't supported, 1720 * so we cannot enable either. 1721 */ 1722 l1parity = l2parity = 0; 1723 } 1724 1725 /* Configure L1 ECC checking */ 1726 if (l1parity) 1727 cp0_ectl |= ERRCTL_PE; 1728 else 1729 cp0_ectl &= ~ERRCTL_PE; 1730 write_c0_ecc(cp0_ectl); 1731 back_to_back_c0_hazard(); 1732 WARN_ON(!!(read_c0_ecc() & ERRCTL_PE) != l1parity); 1733 1734 /* Configure L2 ECC checking */ 1735 if (l2parity) 1736 gcr_ectl |= CM_GCR_ERR_CONTROL_L2_ECC_EN; 1737 else 1738 gcr_ectl &= ~CM_GCR_ERR_CONTROL_L2_ECC_EN; 1739 write_gcr_err_control(gcr_ectl); 1740 gcr_ectl = read_gcr_err_control(); 1741 gcr_ectl &= CM_GCR_ERR_CONTROL_L2_ECC_EN; 1742 WARN_ON(!!gcr_ectl != l2parity); 1743 1744 pr_info("Cache parity protection %sabled\n", 1745 l1parity ? "en" : "dis"); 1746 return; 1747 } 1748 1749 switch (current_cpu_type()) { 1750 case CPU_24K: 1751 case CPU_34K: 1752 case CPU_74K: 1753 case CPU_1004K: 1754 case CPU_1074K: 1755 case CPU_INTERAPTIV: 1756 case CPU_PROAPTIV: 1757 case CPU_P5600: 1758 case CPU_QEMU_GENERIC: 1759 case CPU_P6600: 1760 { 1761 unsigned long errctl; 1762 unsigned int l1parity_present, l2parity_present; 1763 1764 errctl = read_c0_ecc(); 1765 errctl &= ~(ERRCTL_PE|ERRCTL_L2P); 1766 1767 /* probe L1 parity support */ 1768 write_c0_ecc(errctl | ERRCTL_PE); 1769 back_to_back_c0_hazard(); 1770 l1parity_present = (read_c0_ecc() & ERRCTL_PE); 1771 1772 /* probe L2 parity support */ 1773 write_c0_ecc(errctl|ERRCTL_L2P); 1774 back_to_back_c0_hazard(); 1775 l2parity_present = (read_c0_ecc() & ERRCTL_L2P); 1776 1777 if (l1parity_present && l2parity_present) { 1778 if (l1parity) 1779 errctl |= ERRCTL_PE; 1780 if (l1parity ^ l2parity) 1781 errctl |= ERRCTL_L2P; 1782 } else if (l1parity_present) { 1783 if (l1parity) 1784 errctl |= ERRCTL_PE; 1785 } else if (l2parity_present) { 1786 if (l2parity) 1787 errctl |= ERRCTL_L2P; 1788 } else { 1789 /* No parity available */ 1790 } 1791 1792 printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl); 1793 1794 write_c0_ecc(errctl); 1795 back_to_back_c0_hazard(); 1796 errctl = read_c0_ecc(); 1797 printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl); 1798 1799 if (l1parity_present) 1800 printk(KERN_INFO "Cache parity protection %sabled\n", 1801 (errctl & ERRCTL_PE) ? "en" : "dis"); 1802 1803 if (l2parity_present) { 1804 if (l1parity_present && l1parity) 1805 errctl ^= ERRCTL_L2P; 1806 printk(KERN_INFO "L2 cache parity protection %sabled\n", 1807 (errctl & ERRCTL_L2P) ? "en" : "dis"); 1808 } 1809 } 1810 break; 1811 1812 case CPU_5KC: 1813 case CPU_5KE: 1814 case CPU_LOONGSON32: 1815 write_c0_ecc(0x80000000); 1816 back_to_back_c0_hazard(); 1817 /* Set the PE bit (bit 31) in the c0_errctl register. */ 1818 printk(KERN_INFO "Cache parity protection %sabled\n", 1819 (read_c0_ecc() & 0x80000000) ? "en" : "dis"); 1820 break; 1821 case CPU_20KC: 1822 case CPU_25KF: 1823 /* Clear the DE bit (bit 16) in the c0_status register. */ 1824 printk(KERN_INFO "Enable cache parity protection for " 1825 "MIPS 20KC/25KF CPUs.\n"); 1826 clear_c0_status(ST0_DE); 1827 break; 1828 default: 1829 break; 1830 } 1831 } 1832 1833 asmlinkage void cache_parity_error(void) 1834 { 1835 const int field = 2 * sizeof(unsigned long); 1836 unsigned int reg_val; 1837 1838 /* For the moment, report the problem and hang. */ 1839 printk("Cache error exception:\n"); 1840 printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc()); 1841 reg_val = read_c0_cacheerr(); 1842 printk("c0_cacheerr == %08x\n", reg_val); 1843 1844 printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n", 1845 reg_val & (1<<30) ? "secondary" : "primary", 1846 reg_val & (1<<31) ? "data" : "insn"); 1847 if ((cpu_has_mips_r2_r6) && 1848 ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS)) { 1849 pr_err("Error bits: %s%s%s%s%s%s%s%s\n", 1850 reg_val & (1<<29) ? "ED " : "", 1851 reg_val & (1<<28) ? "ET " : "", 1852 reg_val & (1<<27) ? "ES " : "", 1853 reg_val & (1<<26) ? "EE " : "", 1854 reg_val & (1<<25) ? "EB " : "", 1855 reg_val & (1<<24) ? "EI " : "", 1856 reg_val & (1<<23) ? "E1 " : "", 1857 reg_val & (1<<22) ? "E0 " : ""); 1858 } else { 1859 pr_err("Error bits: %s%s%s%s%s%s%s\n", 1860 reg_val & (1<<29) ? "ED " : "", 1861 reg_val & (1<<28) ? "ET " : "", 1862 reg_val & (1<<26) ? "EE " : "", 1863 reg_val & (1<<25) ? "EB " : "", 1864 reg_val & (1<<24) ? "EI " : "", 1865 reg_val & (1<<23) ? "E1 " : "", 1866 reg_val & (1<<22) ? "E0 " : ""); 1867 } 1868 printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1)); 1869 1870 #if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) 1871 if (reg_val & (1<<22)) 1872 printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0()); 1873 1874 if (reg_val & (1<<23)) 1875 printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1()); 1876 #endif 1877 1878 panic("Can't handle the cache error!"); 1879 } 1880 1881 asmlinkage void do_ftlb(void) 1882 { 1883 const int field = 2 * sizeof(unsigned long); 1884 unsigned int reg_val; 1885 1886 /* For the moment, report the problem and hang. */ 1887 if ((cpu_has_mips_r2_r6) && 1888 (((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_MIPS) || 1889 ((current_cpu_data.processor_id & 0xff0000) == PRID_COMP_LOONGSON))) { 1890 pr_err("FTLB error exception, cp0_ecc=0x%08x:\n", 1891 read_c0_ecc()); 1892 pr_err("cp0_errorepc == %0*lx\n", field, read_c0_errorepc()); 1893 reg_val = read_c0_cacheerr(); 1894 pr_err("c0_cacheerr == %08x\n", reg_val); 1895 1896 if ((reg_val & 0xc0000000) == 0xc0000000) { 1897 pr_err("Decoded c0_cacheerr: FTLB parity error\n"); 1898 } else { 1899 pr_err("Decoded c0_cacheerr: %s cache fault in %s reference.\n", 1900 reg_val & (1<<30) ? "secondary" : "primary", 1901 reg_val & (1<<31) ? "data" : "insn"); 1902 } 1903 } else { 1904 pr_err("FTLB error exception\n"); 1905 } 1906 /* Just print the cacheerr bits for now */ 1907 cache_parity_error(); 1908 } 1909 1910 asmlinkage void do_gsexc(struct pt_regs *regs, u32 diag1) 1911 { 1912 u32 exccode = (diag1 & LOONGSON_DIAG1_EXCCODE) >> 1913 LOONGSON_DIAG1_EXCCODE_SHIFT; 1914 enum ctx_state prev_state; 1915 1916 prev_state = exception_enter(); 1917 1918 switch (exccode) { 1919 case 0x08: 1920 /* Undocumented exception, will trigger on certain 1921 * also-undocumented instructions accessible from userspace. 1922 * Processor state is not otherwise corrupted, but currently 1923 * we don't know how to proceed. Maybe there is some 1924 * undocumented control flag to enable the instructions? 1925 */ 1926 force_sig(SIGILL); 1927 break; 1928 1929 default: 1930 /* None of the other exceptions, documented or not, have 1931 * further details given; none are encountered in the wild 1932 * either. Panic in case some of them turn out to be fatal. 1933 */ 1934 show_regs(regs); 1935 panic("Unhandled Loongson exception - GSCause = %08x", diag1); 1936 } 1937 1938 exception_exit(prev_state); 1939 } 1940 1941 /* 1942 * SDBBP EJTAG debug exception handler. 1943 * We skip the instruction and return to the next instruction. 1944 */ 1945 void ejtag_exception_handler(struct pt_regs *regs) 1946 { 1947 const int field = 2 * sizeof(unsigned long); 1948 unsigned long depc, old_epc, old_ra; 1949 unsigned int debug; 1950 1951 printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n"); 1952 depc = read_c0_depc(); 1953 debug = read_c0_debug(); 1954 printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug); 1955 if (debug & 0x80000000) { 1956 /* 1957 * In branch delay slot. 1958 * We cheat a little bit here and use EPC to calculate the 1959 * debug return address (DEPC). EPC is restored after the 1960 * calculation. 1961 */ 1962 old_epc = regs->cp0_epc; 1963 old_ra = regs->regs[31]; 1964 regs->cp0_epc = depc; 1965 compute_return_epc(regs); 1966 depc = regs->cp0_epc; 1967 regs->cp0_epc = old_epc; 1968 regs->regs[31] = old_ra; 1969 } else 1970 depc += 4; 1971 write_c0_depc(depc); 1972 1973 #if 0 1974 printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n"); 1975 write_c0_debug(debug | 0x100); 1976 #endif 1977 } 1978 1979 /* 1980 * NMI exception handler. 1981 * No lock; only written during early bootup by CPU 0. 1982 */ 1983 static RAW_NOTIFIER_HEAD(nmi_chain); 1984 1985 int register_nmi_notifier(struct notifier_block *nb) 1986 { 1987 return raw_notifier_chain_register(&nmi_chain, nb); 1988 } 1989 1990 void __noreturn nmi_exception_handler(struct pt_regs *regs) 1991 { 1992 char str[100]; 1993 1994 nmi_enter(); 1995 raw_notifier_call_chain(&nmi_chain, 0, regs); 1996 bust_spinlocks(1); 1997 snprintf(str, 100, "CPU%d NMI taken, CP0_EPC=%lx\n", 1998 smp_processor_id(), regs->cp0_epc); 1999 regs->cp0_epc = read_c0_errorepc(); 2000 die(str, regs); 2001 nmi_exit(); 2002 } 2003 2004 unsigned long ebase; 2005 EXPORT_SYMBOL_GPL(ebase); 2006 unsigned long exception_handlers[32]; 2007 unsigned long vi_handlers[64]; 2008 2009 void reserve_exception_space(phys_addr_t addr, unsigned long size) 2010 { 2011 /* 2012 * reserve exception space on CPUs other than CPU0 2013 * is too late, since memblock is unavailable when APs 2014 * up 2015 */ 2016 if (smp_processor_id() == 0) 2017 memblock_reserve(addr, size); 2018 } 2019 2020 void __init *set_except_vector(int n, void *addr) 2021 { 2022 unsigned long handler = (unsigned long) addr; 2023 unsigned long old_handler; 2024 2025 #ifdef CONFIG_CPU_MICROMIPS 2026 /* 2027 * Only the TLB handlers are cache aligned with an even 2028 * address. All other handlers are on an odd address and 2029 * require no modification. Otherwise, MIPS32 mode will 2030 * be entered when handling any TLB exceptions. That 2031 * would be bad...since we must stay in microMIPS mode. 2032 */ 2033 if (!(handler & 0x1)) 2034 handler |= 1; 2035 #endif 2036 old_handler = xchg(&exception_handlers[n], handler); 2037 2038 if (n == 0 && cpu_has_divec) { 2039 #ifdef CONFIG_CPU_MICROMIPS 2040 unsigned long jump_mask = ~((1 << 27) - 1); 2041 #else 2042 unsigned long jump_mask = ~((1 << 28) - 1); 2043 #endif 2044 u32 *buf = (u32 *)(ebase + 0x200); 2045 if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) { 2046 uasm_i_j(&buf, handler & ~jump_mask); 2047 uasm_i_nop(&buf); 2048 } else { 2049 UASM_i_LA(&buf, GPR_K0, handler); 2050 uasm_i_jr(&buf, GPR_K0); 2051 uasm_i_nop(&buf); 2052 } 2053 local_flush_icache_range(ebase + 0x200, (unsigned long)buf); 2054 } 2055 return (void *)old_handler; 2056 } 2057 2058 static void do_default_vi(void) 2059 { 2060 show_regs(get_irq_regs()); 2061 panic("Caught unexpected vectored interrupt."); 2062 } 2063 2064 void *set_vi_handler(int n, vi_handler_t addr) 2065 { 2066 extern const u8 except_vec_vi[]; 2067 extern const u8 except_vec_vi_ori[], except_vec_vi_end[]; 2068 extern const u8 rollback_except_vec_vi[]; 2069 unsigned long handler; 2070 unsigned long old_handler = vi_handlers[n]; 2071 int srssets = current_cpu_data.srsets; 2072 u16 *h; 2073 unsigned char *b; 2074 const u8 *vec_start; 2075 int ori_offset; 2076 int handler_len; 2077 2078 BUG_ON(!cpu_has_veic && !cpu_has_vint); 2079 2080 if (addr == NULL) { 2081 handler = (unsigned long) do_default_vi; 2082 } else 2083 handler = (unsigned long) addr; 2084 vi_handlers[n] = handler; 2085 2086 b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING); 2087 2088 if (cpu_has_veic) { 2089 if (board_bind_eic_interrupt) 2090 board_bind_eic_interrupt(n, 0); 2091 } else if (cpu_has_vint) { 2092 /* SRSMap is only defined if shadow sets are implemented */ 2093 if (srssets > 1) 2094 change_c0_srsmap(0xf << n*4, 0 << n*4); 2095 } 2096 2097 vec_start = using_rollback_handler() ? rollback_except_vec_vi : 2098 except_vec_vi; 2099 #if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN) 2100 ori_offset = except_vec_vi_ori - vec_start + 2; 2101 #else 2102 ori_offset = except_vec_vi_ori - vec_start; 2103 #endif 2104 handler_len = except_vec_vi_end - vec_start; 2105 2106 if (handler_len > VECTORSPACING) { 2107 /* 2108 * Sigh... panicing won't help as the console 2109 * is probably not configured :( 2110 */ 2111 panic("VECTORSPACING too small"); 2112 } 2113 2114 set_handler(((unsigned long)b - ebase), vec_start, 2115 #ifdef CONFIG_CPU_MICROMIPS 2116 (handler_len - 1)); 2117 #else 2118 handler_len); 2119 #endif 2120 /* insert offset into vi_handlers[] */ 2121 h = (u16 *)(b + ori_offset); 2122 *h = n * sizeof(handler); 2123 local_flush_icache_range((unsigned long)b, 2124 (unsigned long)(b+handler_len)); 2125 2126 return (void *)old_handler; 2127 } 2128 2129 /* 2130 * Timer interrupt 2131 */ 2132 int cp0_compare_irq; 2133 EXPORT_SYMBOL_GPL(cp0_compare_irq); 2134 int cp0_compare_irq_shift; 2135 2136 /* 2137 * Performance counter IRQ or -1 if shared with timer 2138 */ 2139 int cp0_perfcount_irq; 2140 EXPORT_SYMBOL_GPL(cp0_perfcount_irq); 2141 2142 /* 2143 * Fast debug channel IRQ or -1 if not present 2144 */ 2145 int cp0_fdc_irq; 2146 EXPORT_SYMBOL_GPL(cp0_fdc_irq); 2147 2148 static int noulri; 2149 2150 static int __init ulri_disable(char *s) 2151 { 2152 pr_info("Disabling ulri\n"); 2153 noulri = 1; 2154 2155 return 1; 2156 } 2157 __setup("noulri", ulri_disable); 2158 2159 /* configure STATUS register */ 2160 static void configure_status(void) 2161 { 2162 /* 2163 * Disable coprocessors and select 32-bit or 64-bit addressing 2164 * and the 16/32 or 32/32 FPR register model. Reset the BEV 2165 * flag that some firmware may have left set and the TS bit (for 2166 * IP27). Set XX for ISA IV code to work. 2167 */ 2168 unsigned int status_set = ST0_KERNEL_CUMASK; 2169 #ifdef CONFIG_64BIT 2170 status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX; 2171 #endif 2172 if (current_cpu_data.isa_level & MIPS_CPU_ISA_IV) 2173 status_set |= ST0_XX; 2174 if (cpu_has_dsp) 2175 status_set |= ST0_MX; 2176 2177 change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX, 2178 status_set); 2179 back_to_back_c0_hazard(); 2180 } 2181 2182 unsigned int hwrena; 2183 EXPORT_SYMBOL_GPL(hwrena); 2184 2185 /* configure HWRENA register */ 2186 static void configure_hwrena(void) 2187 { 2188 hwrena = cpu_hwrena_impl_bits; 2189 2190 if (cpu_has_mips_r2_r6) 2191 hwrena |= MIPS_HWRENA_CPUNUM | 2192 MIPS_HWRENA_SYNCISTEP | 2193 MIPS_HWRENA_CC | 2194 MIPS_HWRENA_CCRES; 2195 2196 if (!noulri && cpu_has_userlocal) 2197 hwrena |= MIPS_HWRENA_ULR; 2198 2199 if (hwrena) 2200 write_c0_hwrena(hwrena); 2201 } 2202 2203 static void configure_exception_vector(void) 2204 { 2205 if (cpu_has_mips_r2_r6) { 2206 unsigned long sr = set_c0_status(ST0_BEV); 2207 /* If available, use WG to set top bits of EBASE */ 2208 if (cpu_has_ebase_wg) { 2209 #ifdef CONFIG_64BIT 2210 write_c0_ebase_64(ebase | MIPS_EBASE_WG); 2211 #else 2212 write_c0_ebase(ebase | MIPS_EBASE_WG); 2213 #endif 2214 } 2215 write_c0_ebase(ebase); 2216 write_c0_status(sr); 2217 } 2218 if (cpu_has_veic || cpu_has_vint) { 2219 /* Setting vector spacing enables EI/VI mode */ 2220 change_c0_intctl(0x3e0, VECTORSPACING); 2221 } 2222 if (cpu_has_divec) { 2223 if (cpu_has_mipsmt) { 2224 unsigned int vpflags = dvpe(); 2225 set_c0_cause(CAUSEF_IV); 2226 evpe(vpflags); 2227 } else 2228 set_c0_cause(CAUSEF_IV); 2229 } 2230 } 2231 2232 void per_cpu_trap_init(bool is_boot_cpu) 2233 { 2234 unsigned int cpu = smp_processor_id(); 2235 2236 configure_status(); 2237 configure_hwrena(); 2238 2239 configure_exception_vector(); 2240 2241 /* 2242 * Before R2 both interrupt numbers were fixed to 7, so on R2 only: 2243 * 2244 * o read IntCtl.IPTI to determine the timer interrupt 2245 * o read IntCtl.IPPCI to determine the performance counter interrupt 2246 * o read IntCtl.IPFDC to determine the fast debug channel interrupt 2247 */ 2248 if (cpu_has_mips_r2_r6) { 2249 cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP; 2250 cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7; 2251 cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7; 2252 cp0_fdc_irq = (read_c0_intctl() >> INTCTLB_IPFDC) & 7; 2253 if (!cp0_fdc_irq) 2254 cp0_fdc_irq = -1; 2255 2256 } else { 2257 cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ; 2258 cp0_compare_irq_shift = CP0_LEGACY_PERFCNT_IRQ; 2259 cp0_perfcount_irq = -1; 2260 cp0_fdc_irq = -1; 2261 } 2262 2263 if (cpu_has_mmid) 2264 cpu_data[cpu].asid_cache = 0; 2265 else if (!cpu_data[cpu].asid_cache) 2266 cpu_data[cpu].asid_cache = asid_first_version(cpu); 2267 2268 mmgrab(&init_mm); 2269 current->active_mm = &init_mm; 2270 BUG_ON(current->mm); 2271 enter_lazy_tlb(&init_mm, current); 2272 2273 /* Boot CPU's cache setup in setup_arch(). */ 2274 if (!is_boot_cpu) 2275 cpu_cache_init(); 2276 tlb_init(); 2277 TLBMISS_HANDLER_SETUP(); 2278 } 2279 2280 /* Install CPU exception handler */ 2281 void set_handler(unsigned long offset, const void *addr, unsigned long size) 2282 { 2283 #ifdef CONFIG_CPU_MICROMIPS 2284 memcpy((void *)(ebase + offset), ((unsigned char *)addr - 1), size); 2285 #else 2286 memcpy((void *)(ebase + offset), addr, size); 2287 #endif 2288 local_flush_icache_range(ebase + offset, ebase + offset + size); 2289 } 2290 2291 static const char panic_null_cerr[] = 2292 "Trying to set NULL cache error exception handler\n"; 2293 2294 /* 2295 * Install uncached CPU exception handler. 2296 * This is suitable only for the cache error exception which is the only 2297 * exception handler that is being run uncached. 2298 */ 2299 void set_uncached_handler(unsigned long offset, void *addr, 2300 unsigned long size) 2301 { 2302 unsigned long uncached_ebase = CKSEG1ADDR_OR_64BIT(__pa(ebase)); 2303 2304 if (!addr) 2305 panic(panic_null_cerr); 2306 2307 memcpy((void *)(uncached_ebase + offset), addr, size); 2308 } 2309 2310 static int __initdata rdhwr_noopt; 2311 static int __init set_rdhwr_noopt(char *str) 2312 { 2313 rdhwr_noopt = 1; 2314 return 1; 2315 } 2316 2317 __setup("rdhwr_noopt", set_rdhwr_noopt); 2318 2319 void __init trap_init(void) 2320 { 2321 extern char except_vec3_generic; 2322 extern char except_vec4; 2323 extern char except_vec3_r4000; 2324 unsigned long i, vec_size; 2325 phys_addr_t ebase_pa; 2326 2327 check_wait(); 2328 2329 if (!cpu_has_mips_r2_r6) { 2330 ebase = CAC_BASE; 2331 vec_size = 0x400; 2332 } else { 2333 if (cpu_has_veic || cpu_has_vint) 2334 vec_size = 0x200 + VECTORSPACING*64; 2335 else 2336 vec_size = PAGE_SIZE; 2337 2338 ebase_pa = memblock_phys_alloc(vec_size, 1 << fls(vec_size)); 2339 if (!ebase_pa) 2340 panic("%s: Failed to allocate %lu bytes align=0x%x\n", 2341 __func__, vec_size, 1 << fls(vec_size)); 2342 2343 /* 2344 * Try to ensure ebase resides in KSeg0 if possible. 2345 * 2346 * It shouldn't generally be in XKPhys on MIPS64 to avoid 2347 * hitting a poorly defined exception base for Cache Errors. 2348 * The allocation is likely to be in the low 512MB of physical, 2349 * in which case we should be able to convert to KSeg0. 2350 * 2351 * EVA is special though as it allows segments to be rearranged 2352 * and to become uncached during cache error handling. 2353 */ 2354 if (!IS_ENABLED(CONFIG_EVA) && ebase_pa < 0x20000000) 2355 ebase = CKSEG0ADDR(ebase_pa); 2356 else 2357 ebase = (unsigned long)phys_to_virt(ebase_pa); 2358 if (ebase_pa >= 0x20000000) 2359 pr_warn("ebase(%pa) should better be in KSeg0", 2360 &ebase_pa); 2361 } 2362 2363 if (cpu_has_mmips) { 2364 unsigned int config3 = read_c0_config3(); 2365 2366 if (IS_ENABLED(CONFIG_CPU_MICROMIPS)) 2367 write_c0_config3(config3 | MIPS_CONF3_ISA_OE); 2368 else 2369 write_c0_config3(config3 & ~MIPS_CONF3_ISA_OE); 2370 } 2371 2372 if (board_ebase_setup) 2373 board_ebase_setup(); 2374 per_cpu_trap_init(true); 2375 memblock_set_bottom_up(false); 2376 2377 /* 2378 * Copy the generic exception handlers to their final destination. 2379 * This will be overridden later as suitable for a particular 2380 * configuration. 2381 */ 2382 set_handler(0x180, &except_vec3_generic, 0x80); 2383 2384 /* 2385 * Setup default vectors 2386 */ 2387 for (i = 0; i <= 31; i++) 2388 set_except_vector(i, handle_reserved); 2389 2390 /* 2391 * Copy the EJTAG debug exception vector handler code to its final 2392 * destination. 2393 */ 2394 if (cpu_has_ejtag && board_ejtag_handler_setup) 2395 board_ejtag_handler_setup(); 2396 2397 /* 2398 * Only some CPUs have the watch exceptions. 2399 */ 2400 if (cpu_has_watch) 2401 set_except_vector(EXCCODE_WATCH, handle_watch); 2402 2403 /* 2404 * Initialise interrupt handlers 2405 */ 2406 if (cpu_has_veic || cpu_has_vint) { 2407 int nvec = cpu_has_veic ? 64 : 8; 2408 for (i = 0; i < nvec; i++) 2409 set_vi_handler(i, NULL); 2410 } 2411 else if (cpu_has_divec) 2412 set_handler(0x200, &except_vec4, 0x8); 2413 2414 /* 2415 * Some CPUs can enable/disable for cache parity detection, but does 2416 * it different ways. 2417 */ 2418 parity_protection_init(); 2419 2420 /* 2421 * The Data Bus Errors / Instruction Bus Errors are signaled 2422 * by external hardware. Therefore these two exceptions 2423 * may have board specific handlers. 2424 */ 2425 if (board_be_init) 2426 board_be_init(); 2427 2428 set_except_vector(EXCCODE_INT, using_rollback_handler() ? 2429 rollback_handle_int : handle_int); 2430 set_except_vector(EXCCODE_MOD, handle_tlbm); 2431 set_except_vector(EXCCODE_TLBL, handle_tlbl); 2432 set_except_vector(EXCCODE_TLBS, handle_tlbs); 2433 2434 set_except_vector(EXCCODE_ADEL, handle_adel); 2435 set_except_vector(EXCCODE_ADES, handle_ades); 2436 2437 set_except_vector(EXCCODE_IBE, handle_ibe); 2438 set_except_vector(EXCCODE_DBE, handle_dbe); 2439 2440 set_except_vector(EXCCODE_SYS, handle_sys); 2441 set_except_vector(EXCCODE_BP, handle_bp); 2442 2443 if (rdhwr_noopt) 2444 set_except_vector(EXCCODE_RI, handle_ri); 2445 else { 2446 if (cpu_has_vtag_icache) 2447 set_except_vector(EXCCODE_RI, handle_ri_rdhwr_tlbp); 2448 else if (current_cpu_type() == CPU_LOONGSON64) 2449 set_except_vector(EXCCODE_RI, handle_ri_rdhwr_tlbp); 2450 else 2451 set_except_vector(EXCCODE_RI, handle_ri_rdhwr); 2452 } 2453 2454 set_except_vector(EXCCODE_CPU, handle_cpu); 2455 set_except_vector(EXCCODE_OV, handle_ov); 2456 set_except_vector(EXCCODE_TR, handle_tr); 2457 set_except_vector(EXCCODE_MSAFPE, handle_msa_fpe); 2458 2459 if (board_nmi_handler_setup) 2460 board_nmi_handler_setup(); 2461 2462 if (cpu_has_fpu && !cpu_has_nofpuex) 2463 set_except_vector(EXCCODE_FPE, handle_fpe); 2464 2465 if (cpu_has_ftlbparex) 2466 set_except_vector(MIPS_EXCCODE_TLBPAR, handle_ftlb); 2467 2468 if (cpu_has_gsexcex) 2469 set_except_vector(LOONGSON_EXCCODE_GSEXC, handle_gsexc); 2470 2471 if (cpu_has_rixiex) { 2472 set_except_vector(EXCCODE_TLBRI, tlb_do_page_fault_0); 2473 set_except_vector(EXCCODE_TLBXI, tlb_do_page_fault_0); 2474 } 2475 2476 set_except_vector(EXCCODE_MSADIS, handle_msa); 2477 set_except_vector(EXCCODE_MDMX, handle_mdmx); 2478 2479 if (cpu_has_mcheck) 2480 set_except_vector(EXCCODE_MCHECK, handle_mcheck); 2481 2482 if (cpu_has_mipsmt) 2483 set_except_vector(EXCCODE_THREAD, handle_mt); 2484 2485 set_except_vector(EXCCODE_DSPDIS, handle_dsp); 2486 2487 if (board_cache_error_setup) 2488 board_cache_error_setup(); 2489 2490 if (cpu_has_vce) 2491 /* Special exception: R4[04]00 uses also the divec space. */ 2492 set_handler(0x180, &except_vec3_r4000, 0x100); 2493 else if (cpu_has_4kex) 2494 set_handler(0x180, &except_vec3_generic, 0x80); 2495 else 2496 set_handler(0x080, &except_vec3_generic, 0x80); 2497 2498 local_flush_icache_range(ebase, ebase + vec_size); 2499 2500 sort_extable(__start___dbe_table, __stop___dbe_table); 2501 2502 cu2_notifier(default_cu2_call, 0x80000000); /* Run last */ 2503 } 2504 2505 static int trap_pm_notifier(struct notifier_block *self, unsigned long cmd, 2506 void *v) 2507 { 2508 switch (cmd) { 2509 case CPU_PM_ENTER_FAILED: 2510 case CPU_PM_EXIT: 2511 configure_status(); 2512 configure_hwrena(); 2513 configure_exception_vector(); 2514 2515 /* Restore register with CPU number for TLB handlers */ 2516 TLBMISS_HANDLER_RESTORE(); 2517 2518 break; 2519 } 2520 2521 return NOTIFY_OK; 2522 } 2523 2524 static struct notifier_block trap_pm_notifier_block = { 2525 .notifier_call = trap_pm_notifier, 2526 }; 2527 2528 static int __init trap_pm_init(void) 2529 { 2530 return cpu_pm_register_notifier(&trap_pm_notifier_block); 2531 } 2532 arch_initcall(trap_pm_init); 2533