1 /* 2 * Architecture-specific setup. 3 * 4 * Copyright (C) 1998-2003 Hewlett-Packard Co 5 * David Mosberger-Tang <davidm@hpl.hp.com> 6 * 04/11/17 Ashok Raj <ashok.raj@intel.com> Added CPU Hotplug Support 7 * 8 * 2005-10-07 Keith Owens <kaos@sgi.com> 9 * Add notify_die() hooks. 10 */ 11 #include <linux/cpu.h> 12 #include <linux/pm.h> 13 #include <linux/elf.h> 14 #include <linux/errno.h> 15 #include <linux/kallsyms.h> 16 #include <linux/kernel.h> 17 #include <linux/mm.h> 18 #include <linux/slab.h> 19 #include <linux/module.h> 20 #include <linux/notifier.h> 21 #include <linux/personality.h> 22 #include <linux/sched.h> 23 #include <linux/stddef.h> 24 #include <linux/thread_info.h> 25 #include <linux/unistd.h> 26 #include <linux/efi.h> 27 #include <linux/interrupt.h> 28 #include <linux/delay.h> 29 #include <linux/kdebug.h> 30 #include <linux/utsname.h> 31 #include <linux/tracehook.h> 32 33 #include <asm/cpu.h> 34 #include <asm/delay.h> 35 #include <asm/elf.h> 36 #include <asm/irq.h> 37 #include <asm/kexec.h> 38 #include <asm/pgalloc.h> 39 #include <asm/processor.h> 40 #include <asm/sal.h> 41 #include <asm/switch_to.h> 42 #include <asm/tlbflush.h> 43 #include <asm/uaccess.h> 44 #include <asm/unwind.h> 45 #include <asm/user.h> 46 47 #include "entry.h" 48 49 #ifdef CONFIG_PERFMON 50 # include <asm/perfmon.h> 51 #endif 52 53 #include "sigframe.h" 54 55 void (*ia64_mark_idle)(int); 56 57 unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; 58 EXPORT_SYMBOL(boot_option_idle_override); 59 void (*pm_idle) (void); 60 EXPORT_SYMBOL(pm_idle); 61 void (*pm_power_off) (void); 62 EXPORT_SYMBOL(pm_power_off); 63 64 void 65 ia64_do_show_stack (struct unw_frame_info *info, void *arg) 66 { 67 unsigned long ip, sp, bsp; 68 char buf[128]; /* don't make it so big that it overflows the stack! */ 69 70 printk("\nCall Trace:\n"); 71 do { 72 unw_get_ip(info, &ip); 73 if (ip == 0) 74 break; 75 76 unw_get_sp(info, &sp); 77 unw_get_bsp(info, &bsp); 78 snprintf(buf, sizeof(buf), 79 " [<%016lx>] %%s\n" 80 " sp=%016lx bsp=%016lx\n", 81 ip, sp, bsp); 82 print_symbol(buf, ip); 83 } while (unw_unwind(info) >= 0); 84 } 85 86 void 87 show_stack (struct task_struct *task, unsigned long *sp) 88 { 89 if (!task) 90 unw_init_running(ia64_do_show_stack, NULL); 91 else { 92 struct unw_frame_info info; 93 94 unw_init_from_blocked_task(&info, task); 95 ia64_do_show_stack(&info, NULL); 96 } 97 } 98 99 void 100 dump_stack (void) 101 { 102 show_stack(NULL, NULL); 103 } 104 105 EXPORT_SYMBOL(dump_stack); 106 107 void 108 show_regs (struct pt_regs *regs) 109 { 110 unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri; 111 112 print_modules(); 113 printk("\nPid: %d, CPU %d, comm: %20s\n", task_pid_nr(current), 114 smp_processor_id(), current->comm); 115 printk("psr : %016lx ifs : %016lx ip : [<%016lx>] %s (%s)\n", 116 regs->cr_ipsr, regs->cr_ifs, ip, print_tainted(), 117 init_utsname()->release); 118 print_symbol("ip is at %s\n", ip); 119 printk("unat: %016lx pfs : %016lx rsc : %016lx\n", 120 regs->ar_unat, regs->ar_pfs, regs->ar_rsc); 121 printk("rnat: %016lx bsps: %016lx pr : %016lx\n", 122 regs->ar_rnat, regs->ar_bspstore, regs->pr); 123 printk("ldrs: %016lx ccv : %016lx fpsr: %016lx\n", 124 regs->loadrs, regs->ar_ccv, regs->ar_fpsr); 125 printk("csd : %016lx ssd : %016lx\n", regs->ar_csd, regs->ar_ssd); 126 printk("b0 : %016lx b6 : %016lx b7 : %016lx\n", regs->b0, regs->b6, regs->b7); 127 printk("f6 : %05lx%016lx f7 : %05lx%016lx\n", 128 regs->f6.u.bits[1], regs->f6.u.bits[0], 129 regs->f7.u.bits[1], regs->f7.u.bits[0]); 130 printk("f8 : %05lx%016lx f9 : %05lx%016lx\n", 131 regs->f8.u.bits[1], regs->f8.u.bits[0], 132 regs->f9.u.bits[1], regs->f9.u.bits[0]); 133 printk("f10 : %05lx%016lx f11 : %05lx%016lx\n", 134 regs->f10.u.bits[1], regs->f10.u.bits[0], 135 regs->f11.u.bits[1], regs->f11.u.bits[0]); 136 137 printk("r1 : %016lx r2 : %016lx r3 : %016lx\n", regs->r1, regs->r2, regs->r3); 138 printk("r8 : %016lx r9 : %016lx r10 : %016lx\n", regs->r8, regs->r9, regs->r10); 139 printk("r11 : %016lx r12 : %016lx r13 : %016lx\n", regs->r11, regs->r12, regs->r13); 140 printk("r14 : %016lx r15 : %016lx r16 : %016lx\n", regs->r14, regs->r15, regs->r16); 141 printk("r17 : %016lx r18 : %016lx r19 : %016lx\n", regs->r17, regs->r18, regs->r19); 142 printk("r20 : %016lx r21 : %016lx r22 : %016lx\n", regs->r20, regs->r21, regs->r22); 143 printk("r23 : %016lx r24 : %016lx r25 : %016lx\n", regs->r23, regs->r24, regs->r25); 144 printk("r26 : %016lx r27 : %016lx r28 : %016lx\n", regs->r26, regs->r27, regs->r28); 145 printk("r29 : %016lx r30 : %016lx r31 : %016lx\n", regs->r29, regs->r30, regs->r31); 146 147 if (user_mode(regs)) { 148 /* print the stacked registers */ 149 unsigned long val, *bsp, ndirty; 150 int i, sof, is_nat = 0; 151 152 sof = regs->cr_ifs & 0x7f; /* size of frame */ 153 ndirty = (regs->loadrs >> 19); 154 bsp = ia64_rse_skip_regs((unsigned long *) regs->ar_bspstore, ndirty); 155 for (i = 0; i < sof; ++i) { 156 get_user(val, (unsigned long __user *) ia64_rse_skip_regs(bsp, i)); 157 printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val, 158 ((i == sof - 1) || (i % 3) == 2) ? "\n" : " "); 159 } 160 } else 161 show_stack(NULL, NULL); 162 } 163 164 /* local support for deprecated console_print */ 165 void 166 console_print(const char *s) 167 { 168 printk(KERN_EMERG "%s", s); 169 } 170 171 void 172 do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall) 173 { 174 if (fsys_mode(current, &scr->pt)) { 175 /* 176 * defer signal-handling etc. until we return to 177 * privilege-level 0. 178 */ 179 if (!ia64_psr(&scr->pt)->lp) 180 ia64_psr(&scr->pt)->lp = 1; 181 return; 182 } 183 184 #ifdef CONFIG_PERFMON 185 if (current->thread.pfm_needs_checking) 186 /* 187 * Note: pfm_handle_work() allow us to call it with interrupts 188 * disabled, and may enable interrupts within the function. 189 */ 190 pfm_handle_work(); 191 #endif 192 193 /* deal with pending signal delivery */ 194 if (test_thread_flag(TIF_SIGPENDING)) { 195 local_irq_enable(); /* force interrupt enable */ 196 ia64_do_signal(scr, in_syscall); 197 } 198 199 if (test_thread_flag(TIF_NOTIFY_RESUME)) { 200 clear_thread_flag(TIF_NOTIFY_RESUME); 201 tracehook_notify_resume(&scr->pt); 202 if (current->replacement_session_keyring) 203 key_replace_session_keyring(); 204 } 205 206 /* copy user rbs to kernel rbs */ 207 if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) { 208 local_irq_enable(); /* force interrupt enable */ 209 ia64_sync_krbs(); 210 } 211 212 local_irq_disable(); /* force interrupt disable */ 213 } 214 215 static int pal_halt = 1; 216 static int can_do_pal_halt = 1; 217 218 static int __init nohalt_setup(char * str) 219 { 220 pal_halt = can_do_pal_halt = 0; 221 return 1; 222 } 223 __setup("nohalt", nohalt_setup); 224 225 void 226 update_pal_halt_status(int status) 227 { 228 can_do_pal_halt = pal_halt && status; 229 } 230 231 /* 232 * We use this if we don't have any better idle routine.. 233 */ 234 void 235 default_idle (void) 236 { 237 local_irq_enable(); 238 while (!need_resched()) { 239 if (can_do_pal_halt) { 240 local_irq_disable(); 241 if (!need_resched()) { 242 safe_halt(); 243 } 244 local_irq_enable(); 245 } else 246 cpu_relax(); 247 } 248 } 249 250 #ifdef CONFIG_HOTPLUG_CPU 251 /* We don't actually take CPU down, just spin without interrupts. */ 252 static inline void play_dead(void) 253 { 254 unsigned int this_cpu = smp_processor_id(); 255 256 /* Ack it */ 257 __get_cpu_var(cpu_state) = CPU_DEAD; 258 259 max_xtp(); 260 local_irq_disable(); 261 idle_task_exit(); 262 ia64_jump_to_sal(&sal_boot_rendez_state[this_cpu]); 263 /* 264 * The above is a point of no-return, the processor is 265 * expected to be in SAL loop now. 266 */ 267 BUG(); 268 } 269 #else 270 static inline void play_dead(void) 271 { 272 BUG(); 273 } 274 #endif /* CONFIG_HOTPLUG_CPU */ 275 276 static void do_nothing(void *unused) 277 { 278 } 279 280 /* 281 * cpu_idle_wait - Used to ensure that all the CPUs discard old value of 282 * pm_idle and update to new pm_idle value. Required while changing pm_idle 283 * handler on SMP systems. 284 * 285 * Caller must have changed pm_idle to the new value before the call. Old 286 * pm_idle value will not be used by any CPU after the return of this function. 287 */ 288 void cpu_idle_wait(void) 289 { 290 smp_mb(); 291 /* kick all the CPUs so that they exit out of pm_idle */ 292 smp_call_function(do_nothing, NULL, 1); 293 } 294 EXPORT_SYMBOL_GPL(cpu_idle_wait); 295 296 void __attribute__((noreturn)) 297 cpu_idle (void) 298 { 299 void (*mark_idle)(int) = ia64_mark_idle; 300 int cpu = smp_processor_id(); 301 302 /* endless idle loop with no priority at all */ 303 while (1) { 304 if (can_do_pal_halt) { 305 current_thread_info()->status &= ~TS_POLLING; 306 /* 307 * TS_POLLING-cleared state must be visible before we 308 * test NEED_RESCHED: 309 */ 310 smp_mb(); 311 } else { 312 current_thread_info()->status |= TS_POLLING; 313 } 314 315 if (!need_resched()) { 316 void (*idle)(void); 317 #ifdef CONFIG_SMP 318 min_xtp(); 319 #endif 320 rmb(); 321 if (mark_idle) 322 (*mark_idle)(1); 323 324 idle = pm_idle; 325 if (!idle) 326 idle = default_idle; 327 (*idle)(); 328 if (mark_idle) 329 (*mark_idle)(0); 330 #ifdef CONFIG_SMP 331 normal_xtp(); 332 #endif 333 } 334 schedule_preempt_disabled(); 335 check_pgt_cache(); 336 if (cpu_is_offline(cpu)) 337 play_dead(); 338 } 339 } 340 341 void 342 ia64_save_extra (struct task_struct *task) 343 { 344 #ifdef CONFIG_PERFMON 345 unsigned long info; 346 #endif 347 348 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0) 349 ia64_save_debug_regs(&task->thread.dbr[0]); 350 351 #ifdef CONFIG_PERFMON 352 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0) 353 pfm_save_regs(task); 354 355 info = __get_cpu_var(pfm_syst_info); 356 if (info & PFM_CPUINFO_SYST_WIDE) 357 pfm_syst_wide_update_task(task, info, 0); 358 #endif 359 } 360 361 void 362 ia64_load_extra (struct task_struct *task) 363 { 364 #ifdef CONFIG_PERFMON 365 unsigned long info; 366 #endif 367 368 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0) 369 ia64_load_debug_regs(&task->thread.dbr[0]); 370 371 #ifdef CONFIG_PERFMON 372 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0) 373 pfm_load_regs(task); 374 375 info = __get_cpu_var(pfm_syst_info); 376 if (info & PFM_CPUINFO_SYST_WIDE) 377 pfm_syst_wide_update_task(task, info, 1); 378 #endif 379 } 380 381 /* 382 * Copy the state of an ia-64 thread. 383 * 384 * We get here through the following call chain: 385 * 386 * from user-level: from kernel: 387 * 388 * <clone syscall> <some kernel call frames> 389 * sys_clone : 390 * do_fork do_fork 391 * copy_thread copy_thread 392 * 393 * This means that the stack layout is as follows: 394 * 395 * +---------------------+ (highest addr) 396 * | struct pt_regs | 397 * +---------------------+ 398 * | struct switch_stack | 399 * +---------------------+ 400 * | | 401 * | memory stack | 402 * | | <-- sp (lowest addr) 403 * +---------------------+ 404 * 405 * Observe that we copy the unat values that are in pt_regs and switch_stack. Spilling an 406 * integer to address X causes bit N in ar.unat to be set to the NaT bit of the register, 407 * with N=(X & 0x1ff)/8. Thus, copying the unat value preserves the NaT bits ONLY if the 408 * pt_regs structure in the parent is congruent to that of the child, modulo 512. Since 409 * the stack is page aligned and the page size is at least 4KB, this is always the case, 410 * so there is nothing to worry about. 411 */ 412 int 413 copy_thread(unsigned long clone_flags, 414 unsigned long user_stack_base, unsigned long user_stack_size, 415 struct task_struct *p, struct pt_regs *regs) 416 { 417 extern char ia64_ret_from_clone; 418 struct switch_stack *child_stack, *stack; 419 unsigned long rbs, child_rbs, rbs_size; 420 struct pt_regs *child_ptregs; 421 int retval = 0; 422 423 #ifdef CONFIG_SMP 424 /* 425 * For SMP idle threads, fork_by_hand() calls do_fork with 426 * NULL regs. 427 */ 428 if (!regs) 429 return 0; 430 #endif 431 432 stack = ((struct switch_stack *) regs) - 1; 433 434 child_ptregs = (struct pt_regs *) ((unsigned long) p + IA64_STK_OFFSET) - 1; 435 child_stack = (struct switch_stack *) child_ptregs - 1; 436 437 /* copy parent's switch_stack & pt_regs to child: */ 438 memcpy(child_stack, stack, sizeof(*child_ptregs) + sizeof(*child_stack)); 439 440 rbs = (unsigned long) current + IA64_RBS_OFFSET; 441 child_rbs = (unsigned long) p + IA64_RBS_OFFSET; 442 rbs_size = stack->ar_bspstore - rbs; 443 444 /* copy the parent's register backing store to the child: */ 445 memcpy((void *) child_rbs, (void *) rbs, rbs_size); 446 447 if (likely(user_mode(child_ptregs))) { 448 if (clone_flags & CLONE_SETTLS) 449 child_ptregs->r13 = regs->r16; /* see sys_clone2() in entry.S */ 450 if (user_stack_base) { 451 child_ptregs->r12 = user_stack_base + user_stack_size - 16; 452 child_ptregs->ar_bspstore = user_stack_base; 453 child_ptregs->ar_rnat = 0; 454 child_ptregs->loadrs = 0; 455 } 456 } else { 457 /* 458 * Note: we simply preserve the relative position of 459 * the stack pointer here. There is no need to 460 * allocate a scratch area here, since that will have 461 * been taken care of by the caller of sys_clone() 462 * already. 463 */ 464 child_ptregs->r12 = (unsigned long) child_ptregs - 16; /* kernel sp */ 465 child_ptregs->r13 = (unsigned long) p; /* set `current' pointer */ 466 } 467 child_stack->ar_bspstore = child_rbs + rbs_size; 468 child_stack->b0 = (unsigned long) &ia64_ret_from_clone; 469 470 /* copy parts of thread_struct: */ 471 p->thread.ksp = (unsigned long) child_stack - 16; 472 473 /* stop some PSR bits from being inherited. 474 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve() 475 * therefore we must specify them explicitly here and not include them in 476 * IA64_PSR_BITS_TO_CLEAR. 477 */ 478 child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET) 479 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP)); 480 481 /* 482 * NOTE: The calling convention considers all floating point 483 * registers in the high partition (fph) to be scratch. Since 484 * the only way to get to this point is through a system call, 485 * we know that the values in fph are all dead. Hence, there 486 * is no need to inherit the fph state from the parent to the 487 * child and all we have to do is to make sure that 488 * IA64_THREAD_FPH_VALID is cleared in the child. 489 * 490 * XXX We could push this optimization a bit further by 491 * clearing IA64_THREAD_FPH_VALID on ANY system call. 492 * However, it's not clear this is worth doing. Also, it 493 * would be a slight deviation from the normal Linux system 494 * call behavior where scratch registers are preserved across 495 * system calls (unless used by the system call itself). 496 */ 497 # define THREAD_FLAGS_TO_CLEAR (IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID \ 498 | IA64_THREAD_PM_VALID) 499 # define THREAD_FLAGS_TO_SET 0 500 p->thread.flags = ((current->thread.flags & ~THREAD_FLAGS_TO_CLEAR) 501 | THREAD_FLAGS_TO_SET); 502 ia64_drop_fpu(p); /* don't pick up stale state from a CPU's fph */ 503 504 #ifdef CONFIG_PERFMON 505 if (current->thread.pfm_context) 506 pfm_inherit(p, child_ptregs); 507 #endif 508 return retval; 509 } 510 511 static void 512 do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg) 513 { 514 unsigned long mask, sp, nat_bits = 0, ar_rnat, urbs_end, cfm; 515 unsigned long uninitialized_var(ip); /* GCC be quiet */ 516 elf_greg_t *dst = arg; 517 struct pt_regs *pt; 518 char nat; 519 int i; 520 521 memset(dst, 0, sizeof(elf_gregset_t)); /* don't leak any kernel bits to user-level */ 522 523 if (unw_unwind_to_user(info) < 0) 524 return; 525 526 unw_get_sp(info, &sp); 527 pt = (struct pt_regs *) (sp + 16); 528 529 urbs_end = ia64_get_user_rbs_end(task, pt, &cfm); 530 531 if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0) 532 return; 533 534 ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end), 535 &ar_rnat); 536 537 /* 538 * coredump format: 539 * r0-r31 540 * NaT bits (for r0-r31; bit N == 1 iff rN is a NaT) 541 * predicate registers (p0-p63) 542 * b0-b7 543 * ip cfm user-mask 544 * ar.rsc ar.bsp ar.bspstore ar.rnat 545 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec 546 */ 547 548 /* r0 is zero */ 549 for (i = 1, mask = (1UL << i); i < 32; ++i) { 550 unw_get_gr(info, i, &dst[i], &nat); 551 if (nat) 552 nat_bits |= mask; 553 mask <<= 1; 554 } 555 dst[32] = nat_bits; 556 unw_get_pr(info, &dst[33]); 557 558 for (i = 0; i < 8; ++i) 559 unw_get_br(info, i, &dst[34 + i]); 560 561 unw_get_rp(info, &ip); 562 dst[42] = ip + ia64_psr(pt)->ri; 563 dst[43] = cfm; 564 dst[44] = pt->cr_ipsr & IA64_PSR_UM; 565 566 unw_get_ar(info, UNW_AR_RSC, &dst[45]); 567 /* 568 * For bsp and bspstore, unw_get_ar() would return the kernel 569 * addresses, but we need the user-level addresses instead: 570 */ 571 dst[46] = urbs_end; /* note: by convention PT_AR_BSP points to the end of the urbs! */ 572 dst[47] = pt->ar_bspstore; 573 dst[48] = ar_rnat; 574 unw_get_ar(info, UNW_AR_CCV, &dst[49]); 575 unw_get_ar(info, UNW_AR_UNAT, &dst[50]); 576 unw_get_ar(info, UNW_AR_FPSR, &dst[51]); 577 dst[52] = pt->ar_pfs; /* UNW_AR_PFS is == to pt->cr_ifs for interrupt frames */ 578 unw_get_ar(info, UNW_AR_LC, &dst[53]); 579 unw_get_ar(info, UNW_AR_EC, &dst[54]); 580 unw_get_ar(info, UNW_AR_CSD, &dst[55]); 581 unw_get_ar(info, UNW_AR_SSD, &dst[56]); 582 } 583 584 void 585 do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg) 586 { 587 elf_fpreg_t *dst = arg; 588 int i; 589 590 memset(dst, 0, sizeof(elf_fpregset_t)); /* don't leak any "random" bits */ 591 592 if (unw_unwind_to_user(info) < 0) 593 return; 594 595 /* f0 is 0.0, f1 is 1.0 */ 596 597 for (i = 2; i < 32; ++i) 598 unw_get_fr(info, i, dst + i); 599 600 ia64_flush_fph(task); 601 if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0) 602 memcpy(dst + 32, task->thread.fph, 96*16); 603 } 604 605 void 606 do_copy_regs (struct unw_frame_info *info, void *arg) 607 { 608 do_copy_task_regs(current, info, arg); 609 } 610 611 void 612 do_dump_fpu (struct unw_frame_info *info, void *arg) 613 { 614 do_dump_task_fpu(current, info, arg); 615 } 616 617 void 618 ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst) 619 { 620 unw_init_running(do_copy_regs, dst); 621 } 622 623 int 624 dump_fpu (struct pt_regs *pt, elf_fpregset_t dst) 625 { 626 unw_init_running(do_dump_fpu, dst); 627 return 1; /* f0-f31 are always valid so we always return 1 */ 628 } 629 630 long 631 sys_execve (const char __user *filename, 632 const char __user *const __user *argv, 633 const char __user *const __user *envp, 634 struct pt_regs *regs) 635 { 636 char *fname; 637 int error; 638 639 fname = getname(filename); 640 error = PTR_ERR(fname); 641 if (IS_ERR(fname)) 642 goto out; 643 error = do_execve(fname, argv, envp, regs); 644 putname(fname); 645 out: 646 return error; 647 } 648 649 pid_t 650 kernel_thread (int (*fn)(void *), void *arg, unsigned long flags) 651 { 652 extern void start_kernel_thread (void); 653 unsigned long *helper_fptr = (unsigned long *) &start_kernel_thread; 654 struct { 655 struct switch_stack sw; 656 struct pt_regs pt; 657 } regs; 658 659 memset(®s, 0, sizeof(regs)); 660 regs.pt.cr_iip = helper_fptr[0]; /* set entry point (IP) */ 661 regs.pt.r1 = helper_fptr[1]; /* set GP */ 662 regs.pt.r9 = (unsigned long) fn; /* 1st argument */ 663 regs.pt.r11 = (unsigned long) arg; /* 2nd argument */ 664 /* Preserve PSR bits, except for bits 32-34 and 37-45, which we can't read. */ 665 regs.pt.cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN; 666 regs.pt.cr_ifs = 1UL << 63; /* mark as valid, empty frame */ 667 regs.sw.ar_fpsr = regs.pt.ar_fpsr = ia64_getreg(_IA64_REG_AR_FPSR); 668 regs.sw.ar_bspstore = (unsigned long) current + IA64_RBS_OFFSET; 669 regs.sw.pr = (1 << PRED_KERNEL_STACK); 670 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s.pt, 0, NULL, NULL); 671 } 672 EXPORT_SYMBOL(kernel_thread); 673 674 /* This gets called from kernel_thread() via ia64_invoke_thread_helper(). */ 675 int 676 kernel_thread_helper (int (*fn)(void *), void *arg) 677 { 678 return (*fn)(arg); 679 } 680 681 /* 682 * Flush thread state. This is called when a thread does an execve(). 683 */ 684 void 685 flush_thread (void) 686 { 687 /* drop floating-point and debug-register state if it exists: */ 688 current->thread.flags &= ~(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID); 689 ia64_drop_fpu(current); 690 } 691 692 /* 693 * Clean up state associated with current thread. This is called when 694 * the thread calls exit(). 695 */ 696 void 697 exit_thread (void) 698 { 699 700 ia64_drop_fpu(current); 701 #ifdef CONFIG_PERFMON 702 /* if needed, stop monitoring and flush state to perfmon context */ 703 if (current->thread.pfm_context) 704 pfm_exit_thread(current); 705 706 /* free debug register resources */ 707 if (current->thread.flags & IA64_THREAD_DBG_VALID) 708 pfm_release_debug_registers(current); 709 #endif 710 } 711 712 unsigned long 713 get_wchan (struct task_struct *p) 714 { 715 struct unw_frame_info info; 716 unsigned long ip; 717 int count = 0; 718 719 if (!p || p == current || p->state == TASK_RUNNING) 720 return 0; 721 722 /* 723 * Note: p may not be a blocked task (it could be current or 724 * another process running on some other CPU. Rather than 725 * trying to determine if p is really blocked, we just assume 726 * it's blocked and rely on the unwind routines to fail 727 * gracefully if the process wasn't really blocked after all. 728 * --davidm 99/12/15 729 */ 730 unw_init_from_blocked_task(&info, p); 731 do { 732 if (p->state == TASK_RUNNING) 733 return 0; 734 if (unw_unwind(&info) < 0) 735 return 0; 736 unw_get_ip(&info, &ip); 737 if (!in_sched_functions(ip)) 738 return ip; 739 } while (count++ < 16); 740 return 0; 741 } 742 743 void 744 cpu_halt (void) 745 { 746 pal_power_mgmt_info_u_t power_info[8]; 747 unsigned long min_power; 748 int i, min_power_state; 749 750 if (ia64_pal_halt_info(power_info) != 0) 751 return; 752 753 min_power_state = 0; 754 min_power = power_info[0].pal_power_mgmt_info_s.power_consumption; 755 for (i = 1; i < 8; ++i) 756 if (power_info[i].pal_power_mgmt_info_s.im 757 && power_info[i].pal_power_mgmt_info_s.power_consumption < min_power) { 758 min_power = power_info[i].pal_power_mgmt_info_s.power_consumption; 759 min_power_state = i; 760 } 761 762 while (1) 763 ia64_pal_halt(min_power_state); 764 } 765 766 void machine_shutdown(void) 767 { 768 #ifdef CONFIG_HOTPLUG_CPU 769 int cpu; 770 771 for_each_online_cpu(cpu) { 772 if (cpu != smp_processor_id()) 773 cpu_down(cpu); 774 } 775 #endif 776 #ifdef CONFIG_KEXEC 777 kexec_disable_iosapic(); 778 #endif 779 } 780 781 void 782 machine_restart (char *restart_cmd) 783 { 784 (void) notify_die(DIE_MACHINE_RESTART, restart_cmd, NULL, 0, 0, 0); 785 (*efi.reset_system)(EFI_RESET_WARM, 0, 0, NULL); 786 } 787 788 void 789 machine_halt (void) 790 { 791 (void) notify_die(DIE_MACHINE_HALT, "", NULL, 0, 0, 0); 792 cpu_halt(); 793 } 794 795 void 796 machine_power_off (void) 797 { 798 if (pm_power_off) 799 pm_power_off(); 800 machine_halt(); 801 } 802 803