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/tlbflush.h> 42 #include <asm/uaccess.h> 43 #include <asm/unwind.h> 44 #include <asm/user.h> 45 46 #include "entry.h" 47 48 #ifdef CONFIG_PERFMON 49 # include <asm/perfmon.h> 50 #endif 51 52 #include "sigframe.h" 53 54 void (*ia64_mark_idle)(int); 55 56 unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; 57 EXPORT_SYMBOL(boot_option_idle_override); 58 void (*pm_idle) (void); 59 EXPORT_SYMBOL(pm_idle); 60 void (*pm_power_off) (void); 61 EXPORT_SYMBOL(pm_power_off); 62 63 void 64 ia64_do_show_stack (struct unw_frame_info *info, void *arg) 65 { 66 unsigned long ip, sp, bsp; 67 char buf[128]; /* don't make it so big that it overflows the stack! */ 68 69 printk("\nCall Trace:\n"); 70 do { 71 unw_get_ip(info, &ip); 72 if (ip == 0) 73 break; 74 75 unw_get_sp(info, &sp); 76 unw_get_bsp(info, &bsp); 77 snprintf(buf, sizeof(buf), 78 " [<%016lx>] %%s\n" 79 " sp=%016lx bsp=%016lx\n", 80 ip, sp, bsp); 81 print_symbol(buf, ip); 82 } while (unw_unwind(info) >= 0); 83 } 84 85 void 86 show_stack (struct task_struct *task, unsigned long *sp) 87 { 88 if (!task) 89 unw_init_running(ia64_do_show_stack, NULL); 90 else { 91 struct unw_frame_info info; 92 93 unw_init_from_blocked_task(&info, task); 94 ia64_do_show_stack(&info, NULL); 95 } 96 } 97 98 void 99 dump_stack (void) 100 { 101 show_stack(NULL, NULL); 102 } 103 104 EXPORT_SYMBOL(dump_stack); 105 106 void 107 show_regs (struct pt_regs *regs) 108 { 109 unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri; 110 111 print_modules(); 112 printk("\nPid: %d, CPU %d, comm: %20s\n", task_pid_nr(current), 113 smp_processor_id(), current->comm); 114 printk("psr : %016lx ifs : %016lx ip : [<%016lx>] %s (%s)\n", 115 regs->cr_ipsr, regs->cr_ifs, ip, print_tainted(), 116 init_utsname()->release); 117 print_symbol("ip is at %s\n", ip); 118 printk("unat: %016lx pfs : %016lx rsc : %016lx\n", 119 regs->ar_unat, regs->ar_pfs, regs->ar_rsc); 120 printk("rnat: %016lx bsps: %016lx pr : %016lx\n", 121 regs->ar_rnat, regs->ar_bspstore, regs->pr); 122 printk("ldrs: %016lx ccv : %016lx fpsr: %016lx\n", 123 regs->loadrs, regs->ar_ccv, regs->ar_fpsr); 124 printk("csd : %016lx ssd : %016lx\n", regs->ar_csd, regs->ar_ssd); 125 printk("b0 : %016lx b6 : %016lx b7 : %016lx\n", regs->b0, regs->b6, regs->b7); 126 printk("f6 : %05lx%016lx f7 : %05lx%016lx\n", 127 regs->f6.u.bits[1], regs->f6.u.bits[0], 128 regs->f7.u.bits[1], regs->f7.u.bits[0]); 129 printk("f8 : %05lx%016lx f9 : %05lx%016lx\n", 130 regs->f8.u.bits[1], regs->f8.u.bits[0], 131 regs->f9.u.bits[1], regs->f9.u.bits[0]); 132 printk("f10 : %05lx%016lx f11 : %05lx%016lx\n", 133 regs->f10.u.bits[1], regs->f10.u.bits[0], 134 regs->f11.u.bits[1], regs->f11.u.bits[0]); 135 136 printk("r1 : %016lx r2 : %016lx r3 : %016lx\n", regs->r1, regs->r2, regs->r3); 137 printk("r8 : %016lx r9 : %016lx r10 : %016lx\n", regs->r8, regs->r9, regs->r10); 138 printk("r11 : %016lx r12 : %016lx r13 : %016lx\n", regs->r11, regs->r12, regs->r13); 139 printk("r14 : %016lx r15 : %016lx r16 : %016lx\n", regs->r14, regs->r15, regs->r16); 140 printk("r17 : %016lx r18 : %016lx r19 : %016lx\n", regs->r17, regs->r18, regs->r19); 141 printk("r20 : %016lx r21 : %016lx r22 : %016lx\n", regs->r20, regs->r21, regs->r22); 142 printk("r23 : %016lx r24 : %016lx r25 : %016lx\n", regs->r23, regs->r24, regs->r25); 143 printk("r26 : %016lx r27 : %016lx r28 : %016lx\n", regs->r26, regs->r27, regs->r28); 144 printk("r29 : %016lx r30 : %016lx r31 : %016lx\n", regs->r29, regs->r30, regs->r31); 145 146 if (user_mode(regs)) { 147 /* print the stacked registers */ 148 unsigned long val, *bsp, ndirty; 149 int i, sof, is_nat = 0; 150 151 sof = regs->cr_ifs & 0x7f; /* size of frame */ 152 ndirty = (regs->loadrs >> 19); 153 bsp = ia64_rse_skip_regs((unsigned long *) regs->ar_bspstore, ndirty); 154 for (i = 0; i < sof; ++i) { 155 get_user(val, (unsigned long __user *) ia64_rse_skip_regs(bsp, i)); 156 printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val, 157 ((i == sof - 1) || (i % 3) == 2) ? "\n" : " "); 158 } 159 } else 160 show_stack(NULL, NULL); 161 } 162 163 /* local support for deprecated console_print */ 164 void 165 console_print(const char *s) 166 { 167 printk(KERN_EMERG "%s", s); 168 } 169 170 void 171 do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall) 172 { 173 if (fsys_mode(current, &scr->pt)) { 174 /* 175 * defer signal-handling etc. until we return to 176 * privilege-level 0. 177 */ 178 if (!ia64_psr(&scr->pt)->lp) 179 ia64_psr(&scr->pt)->lp = 1; 180 return; 181 } 182 183 #ifdef CONFIG_PERFMON 184 if (current->thread.pfm_needs_checking) 185 /* 186 * Note: pfm_handle_work() allow us to call it with interrupts 187 * disabled, and may enable interrupts within the function. 188 */ 189 pfm_handle_work(); 190 #endif 191 192 /* deal with pending signal delivery */ 193 if (test_thread_flag(TIF_SIGPENDING)) { 194 local_irq_enable(); /* force interrupt enable */ 195 ia64_do_signal(scr, in_syscall); 196 } 197 198 if (test_thread_flag(TIF_NOTIFY_RESUME)) { 199 clear_thread_flag(TIF_NOTIFY_RESUME); 200 tracehook_notify_resume(&scr->pt); 201 if (current->replacement_session_keyring) 202 key_replace_session_keyring(); 203 } 204 205 /* copy user rbs to kernel rbs */ 206 if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) { 207 local_irq_enable(); /* force interrupt enable */ 208 ia64_sync_krbs(); 209 } 210 211 local_irq_disable(); /* force interrupt disable */ 212 } 213 214 static int pal_halt = 1; 215 static int can_do_pal_halt = 1; 216 217 static int __init nohalt_setup(char * str) 218 { 219 pal_halt = can_do_pal_halt = 0; 220 return 1; 221 } 222 __setup("nohalt", nohalt_setup); 223 224 void 225 update_pal_halt_status(int status) 226 { 227 can_do_pal_halt = pal_halt && status; 228 } 229 230 /* 231 * We use this if we don't have any better idle routine.. 232 */ 233 void 234 default_idle (void) 235 { 236 local_irq_enable(); 237 while (!need_resched()) { 238 if (can_do_pal_halt) { 239 local_irq_disable(); 240 if (!need_resched()) { 241 safe_halt(); 242 } 243 local_irq_enable(); 244 } else 245 cpu_relax(); 246 } 247 } 248 249 #ifdef CONFIG_HOTPLUG_CPU 250 /* We don't actually take CPU down, just spin without interrupts. */ 251 static inline void play_dead(void) 252 { 253 unsigned int this_cpu = smp_processor_id(); 254 255 /* Ack it */ 256 __get_cpu_var(cpu_state) = CPU_DEAD; 257 258 max_xtp(); 259 local_irq_disable(); 260 idle_task_exit(); 261 ia64_jump_to_sal(&sal_boot_rendez_state[this_cpu]); 262 /* 263 * The above is a point of no-return, the processor is 264 * expected to be in SAL loop now. 265 */ 266 BUG(); 267 } 268 #else 269 static inline void play_dead(void) 270 { 271 BUG(); 272 } 273 #endif /* CONFIG_HOTPLUG_CPU */ 274 275 static void do_nothing(void *unused) 276 { 277 } 278 279 /* 280 * cpu_idle_wait - Used to ensure that all the CPUs discard old value of 281 * pm_idle and update to new pm_idle value. Required while changing pm_idle 282 * handler on SMP systems. 283 * 284 * Caller must have changed pm_idle to the new value before the call. Old 285 * pm_idle value will not be used by any CPU after the return of this function. 286 */ 287 void cpu_idle_wait(void) 288 { 289 smp_mb(); 290 /* kick all the CPUs so that they exit out of pm_idle */ 291 smp_call_function(do_nothing, NULL, 1); 292 } 293 EXPORT_SYMBOL_GPL(cpu_idle_wait); 294 295 void __attribute__((noreturn)) 296 cpu_idle (void) 297 { 298 void (*mark_idle)(int) = ia64_mark_idle; 299 int cpu = smp_processor_id(); 300 301 /* endless idle loop with no priority at all */ 302 while (1) { 303 if (can_do_pal_halt) { 304 current_thread_info()->status &= ~TS_POLLING; 305 /* 306 * TS_POLLING-cleared state must be visible before we 307 * test NEED_RESCHED: 308 */ 309 smp_mb(); 310 } else { 311 current_thread_info()->status |= TS_POLLING; 312 } 313 314 if (!need_resched()) { 315 void (*idle)(void); 316 #ifdef CONFIG_SMP 317 min_xtp(); 318 #endif 319 rmb(); 320 if (mark_idle) 321 (*mark_idle)(1); 322 323 idle = pm_idle; 324 if (!idle) 325 idle = default_idle; 326 (*idle)(); 327 if (mark_idle) 328 (*mark_idle)(0); 329 #ifdef CONFIG_SMP 330 normal_xtp(); 331 #endif 332 } 333 preempt_enable_no_resched(); 334 schedule(); 335 preempt_disable(); 336 check_pgt_cache(); 337 if (cpu_is_offline(cpu)) 338 play_dead(); 339 } 340 } 341 342 void 343 ia64_save_extra (struct task_struct *task) 344 { 345 #ifdef CONFIG_PERFMON 346 unsigned long info; 347 #endif 348 349 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0) 350 ia64_save_debug_regs(&task->thread.dbr[0]); 351 352 #ifdef CONFIG_PERFMON 353 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0) 354 pfm_save_regs(task); 355 356 info = __get_cpu_var(pfm_syst_info); 357 if (info & PFM_CPUINFO_SYST_WIDE) 358 pfm_syst_wide_update_task(task, info, 0); 359 #endif 360 } 361 362 void 363 ia64_load_extra (struct task_struct *task) 364 { 365 #ifdef CONFIG_PERFMON 366 unsigned long info; 367 #endif 368 369 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0) 370 ia64_load_debug_regs(&task->thread.dbr[0]); 371 372 #ifdef CONFIG_PERFMON 373 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0) 374 pfm_load_regs(task); 375 376 info = __get_cpu_var(pfm_syst_info); 377 if (info & PFM_CPUINFO_SYST_WIDE) 378 pfm_syst_wide_update_task(task, info, 1); 379 #endif 380 } 381 382 /* 383 * Copy the state of an ia-64 thread. 384 * 385 * We get here through the following call chain: 386 * 387 * from user-level: from kernel: 388 * 389 * <clone syscall> <some kernel call frames> 390 * sys_clone : 391 * do_fork do_fork 392 * copy_thread copy_thread 393 * 394 * This means that the stack layout is as follows: 395 * 396 * +---------------------+ (highest addr) 397 * | struct pt_regs | 398 * +---------------------+ 399 * | struct switch_stack | 400 * +---------------------+ 401 * | | 402 * | memory stack | 403 * | | <-- sp (lowest addr) 404 * +---------------------+ 405 * 406 * Observe that we copy the unat values that are in pt_regs and switch_stack. Spilling an 407 * integer to address X causes bit N in ar.unat to be set to the NaT bit of the register, 408 * with N=(X & 0x1ff)/8. Thus, copying the unat value preserves the NaT bits ONLY if the 409 * pt_regs structure in the parent is congruent to that of the child, modulo 512. Since 410 * the stack is page aligned and the page size is at least 4KB, this is always the case, 411 * so there is nothing to worry about. 412 */ 413 int 414 copy_thread(unsigned long clone_flags, 415 unsigned long user_stack_base, unsigned long user_stack_size, 416 struct task_struct *p, struct pt_regs *regs) 417 { 418 extern char ia64_ret_from_clone; 419 struct switch_stack *child_stack, *stack; 420 unsigned long rbs, child_rbs, rbs_size; 421 struct pt_regs *child_ptregs; 422 int retval = 0; 423 424 #ifdef CONFIG_SMP 425 /* 426 * For SMP idle threads, fork_by_hand() calls do_fork with 427 * NULL regs. 428 */ 429 if (!regs) 430 return 0; 431 #endif 432 433 stack = ((struct switch_stack *) regs) - 1; 434 435 child_ptregs = (struct pt_regs *) ((unsigned long) p + IA64_STK_OFFSET) - 1; 436 child_stack = (struct switch_stack *) child_ptregs - 1; 437 438 /* copy parent's switch_stack & pt_regs to child: */ 439 memcpy(child_stack, stack, sizeof(*child_ptregs) + sizeof(*child_stack)); 440 441 rbs = (unsigned long) current + IA64_RBS_OFFSET; 442 child_rbs = (unsigned long) p + IA64_RBS_OFFSET; 443 rbs_size = stack->ar_bspstore - rbs; 444 445 /* copy the parent's register backing store to the child: */ 446 memcpy((void *) child_rbs, (void *) rbs, rbs_size); 447 448 if (likely(user_mode(child_ptregs))) { 449 if (clone_flags & CLONE_SETTLS) 450 child_ptregs->r13 = regs->r16; /* see sys_clone2() in entry.S */ 451 if (user_stack_base) { 452 child_ptregs->r12 = user_stack_base + user_stack_size - 16; 453 child_ptregs->ar_bspstore = user_stack_base; 454 child_ptregs->ar_rnat = 0; 455 child_ptregs->loadrs = 0; 456 } 457 } else { 458 /* 459 * Note: we simply preserve the relative position of 460 * the stack pointer here. There is no need to 461 * allocate a scratch area here, since that will have 462 * been taken care of by the caller of sys_clone() 463 * already. 464 */ 465 child_ptregs->r12 = (unsigned long) child_ptregs - 16; /* kernel sp */ 466 child_ptregs->r13 = (unsigned long) p; /* set `current' pointer */ 467 } 468 child_stack->ar_bspstore = child_rbs + rbs_size; 469 child_stack->b0 = (unsigned long) &ia64_ret_from_clone; 470 471 /* copy parts of thread_struct: */ 472 p->thread.ksp = (unsigned long) child_stack - 16; 473 474 /* stop some PSR bits from being inherited. 475 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve() 476 * therefore we must specify them explicitly here and not include them in 477 * IA64_PSR_BITS_TO_CLEAR. 478 */ 479 child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET) 480 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP)); 481 482 /* 483 * NOTE: The calling convention considers all floating point 484 * registers in the high partition (fph) to be scratch. Since 485 * the only way to get to this point is through a system call, 486 * we know that the values in fph are all dead. Hence, there 487 * is no need to inherit the fph state from the parent to the 488 * child and all we have to do is to make sure that 489 * IA64_THREAD_FPH_VALID is cleared in the child. 490 * 491 * XXX We could push this optimization a bit further by 492 * clearing IA64_THREAD_FPH_VALID on ANY system call. 493 * However, it's not clear this is worth doing. Also, it 494 * would be a slight deviation from the normal Linux system 495 * call behavior where scratch registers are preserved across 496 * system calls (unless used by the system call itself). 497 */ 498 # define THREAD_FLAGS_TO_CLEAR (IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID \ 499 | IA64_THREAD_PM_VALID) 500 # define THREAD_FLAGS_TO_SET 0 501 p->thread.flags = ((current->thread.flags & ~THREAD_FLAGS_TO_CLEAR) 502 | THREAD_FLAGS_TO_SET); 503 ia64_drop_fpu(p); /* don't pick up stale state from a CPU's fph */ 504 505 #ifdef CONFIG_PERFMON 506 if (current->thread.pfm_context) 507 pfm_inherit(p, child_ptregs); 508 #endif 509 return retval; 510 } 511 512 static void 513 do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg) 514 { 515 unsigned long mask, sp, nat_bits = 0, ar_rnat, urbs_end, cfm; 516 unsigned long uninitialized_var(ip); /* GCC be quiet */ 517 elf_greg_t *dst = arg; 518 struct pt_regs *pt; 519 char nat; 520 int i; 521 522 memset(dst, 0, sizeof(elf_gregset_t)); /* don't leak any kernel bits to user-level */ 523 524 if (unw_unwind_to_user(info) < 0) 525 return; 526 527 unw_get_sp(info, &sp); 528 pt = (struct pt_regs *) (sp + 16); 529 530 urbs_end = ia64_get_user_rbs_end(task, pt, &cfm); 531 532 if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0) 533 return; 534 535 ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end), 536 &ar_rnat); 537 538 /* 539 * coredump format: 540 * r0-r31 541 * NaT bits (for r0-r31; bit N == 1 iff rN is a NaT) 542 * predicate registers (p0-p63) 543 * b0-b7 544 * ip cfm user-mask 545 * ar.rsc ar.bsp ar.bspstore ar.rnat 546 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec 547 */ 548 549 /* r0 is zero */ 550 for (i = 1, mask = (1UL << i); i < 32; ++i) { 551 unw_get_gr(info, i, &dst[i], &nat); 552 if (nat) 553 nat_bits |= mask; 554 mask <<= 1; 555 } 556 dst[32] = nat_bits; 557 unw_get_pr(info, &dst[33]); 558 559 for (i = 0; i < 8; ++i) 560 unw_get_br(info, i, &dst[34 + i]); 561 562 unw_get_rp(info, &ip); 563 dst[42] = ip + ia64_psr(pt)->ri; 564 dst[43] = cfm; 565 dst[44] = pt->cr_ipsr & IA64_PSR_UM; 566 567 unw_get_ar(info, UNW_AR_RSC, &dst[45]); 568 /* 569 * For bsp and bspstore, unw_get_ar() would return the kernel 570 * addresses, but we need the user-level addresses instead: 571 */ 572 dst[46] = urbs_end; /* note: by convention PT_AR_BSP points to the end of the urbs! */ 573 dst[47] = pt->ar_bspstore; 574 dst[48] = ar_rnat; 575 unw_get_ar(info, UNW_AR_CCV, &dst[49]); 576 unw_get_ar(info, UNW_AR_UNAT, &dst[50]); 577 unw_get_ar(info, UNW_AR_FPSR, &dst[51]); 578 dst[52] = pt->ar_pfs; /* UNW_AR_PFS is == to pt->cr_ifs for interrupt frames */ 579 unw_get_ar(info, UNW_AR_LC, &dst[53]); 580 unw_get_ar(info, UNW_AR_EC, &dst[54]); 581 unw_get_ar(info, UNW_AR_CSD, &dst[55]); 582 unw_get_ar(info, UNW_AR_SSD, &dst[56]); 583 } 584 585 void 586 do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg) 587 { 588 elf_fpreg_t *dst = arg; 589 int i; 590 591 memset(dst, 0, sizeof(elf_fpregset_t)); /* don't leak any "random" bits */ 592 593 if (unw_unwind_to_user(info) < 0) 594 return; 595 596 /* f0 is 0.0, f1 is 1.0 */ 597 598 for (i = 2; i < 32; ++i) 599 unw_get_fr(info, i, dst + i); 600 601 ia64_flush_fph(task); 602 if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0) 603 memcpy(dst + 32, task->thread.fph, 96*16); 604 } 605 606 void 607 do_copy_regs (struct unw_frame_info *info, void *arg) 608 { 609 do_copy_task_regs(current, info, arg); 610 } 611 612 void 613 do_dump_fpu (struct unw_frame_info *info, void *arg) 614 { 615 do_dump_task_fpu(current, info, arg); 616 } 617 618 void 619 ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst) 620 { 621 unw_init_running(do_copy_regs, dst); 622 } 623 624 int 625 dump_fpu (struct pt_regs *pt, elf_fpregset_t dst) 626 { 627 unw_init_running(do_dump_fpu, dst); 628 return 1; /* f0-f31 are always valid so we always return 1 */ 629 } 630 631 long 632 sys_execve (const char __user *filename, 633 const char __user *const __user *argv, 634 const char __user *const __user *envp, 635 struct pt_regs *regs) 636 { 637 char *fname; 638 int error; 639 640 fname = getname(filename); 641 error = PTR_ERR(fname); 642 if (IS_ERR(fname)) 643 goto out; 644 error = do_execve(fname, argv, envp, regs); 645 putname(fname); 646 out: 647 return error; 648 } 649 650 pid_t 651 kernel_thread (int (*fn)(void *), void *arg, unsigned long flags) 652 { 653 extern void start_kernel_thread (void); 654 unsigned long *helper_fptr = (unsigned long *) &start_kernel_thread; 655 struct { 656 struct switch_stack sw; 657 struct pt_regs pt; 658 } regs; 659 660 memset(®s, 0, sizeof(regs)); 661 regs.pt.cr_iip = helper_fptr[0]; /* set entry point (IP) */ 662 regs.pt.r1 = helper_fptr[1]; /* set GP */ 663 regs.pt.r9 = (unsigned long) fn; /* 1st argument */ 664 regs.pt.r11 = (unsigned long) arg; /* 2nd argument */ 665 /* Preserve PSR bits, except for bits 32-34 and 37-45, which we can't read. */ 666 regs.pt.cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN; 667 regs.pt.cr_ifs = 1UL << 63; /* mark as valid, empty frame */ 668 regs.sw.ar_fpsr = regs.pt.ar_fpsr = ia64_getreg(_IA64_REG_AR_FPSR); 669 regs.sw.ar_bspstore = (unsigned long) current + IA64_RBS_OFFSET; 670 regs.sw.pr = (1 << PRED_KERNEL_STACK); 671 return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s.pt, 0, NULL, NULL); 672 } 673 EXPORT_SYMBOL(kernel_thread); 674 675 /* This gets called from kernel_thread() via ia64_invoke_thread_helper(). */ 676 int 677 kernel_thread_helper (int (*fn)(void *), void *arg) 678 { 679 return (*fn)(arg); 680 } 681 682 /* 683 * Flush thread state. This is called when a thread does an execve(). 684 */ 685 void 686 flush_thread (void) 687 { 688 /* drop floating-point and debug-register state if it exists: */ 689 current->thread.flags &= ~(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID); 690 ia64_drop_fpu(current); 691 } 692 693 /* 694 * Clean up state associated with current thread. This is called when 695 * the thread calls exit(). 696 */ 697 void 698 exit_thread (void) 699 { 700 701 ia64_drop_fpu(current); 702 #ifdef CONFIG_PERFMON 703 /* if needed, stop monitoring and flush state to perfmon context */ 704 if (current->thread.pfm_context) 705 pfm_exit_thread(current); 706 707 /* free debug register resources */ 708 if (current->thread.flags & IA64_THREAD_DBG_VALID) 709 pfm_release_debug_registers(current); 710 #endif 711 } 712 713 unsigned long 714 get_wchan (struct task_struct *p) 715 { 716 struct unw_frame_info info; 717 unsigned long ip; 718 int count = 0; 719 720 if (!p || p == current || p->state == TASK_RUNNING) 721 return 0; 722 723 /* 724 * Note: p may not be a blocked task (it could be current or 725 * another process running on some other CPU. Rather than 726 * trying to determine if p is really blocked, we just assume 727 * it's blocked and rely on the unwind routines to fail 728 * gracefully if the process wasn't really blocked after all. 729 * --davidm 99/12/15 730 */ 731 unw_init_from_blocked_task(&info, p); 732 do { 733 if (p->state == TASK_RUNNING) 734 return 0; 735 if (unw_unwind(&info) < 0) 736 return 0; 737 unw_get_ip(&info, &ip); 738 if (!in_sched_functions(ip)) 739 return ip; 740 } while (count++ < 16); 741 return 0; 742 } 743 744 void 745 cpu_halt (void) 746 { 747 pal_power_mgmt_info_u_t power_info[8]; 748 unsigned long min_power; 749 int i, min_power_state; 750 751 if (ia64_pal_halt_info(power_info) != 0) 752 return; 753 754 min_power_state = 0; 755 min_power = power_info[0].pal_power_mgmt_info_s.power_consumption; 756 for (i = 1; i < 8; ++i) 757 if (power_info[i].pal_power_mgmt_info_s.im 758 && power_info[i].pal_power_mgmt_info_s.power_consumption < min_power) { 759 min_power = power_info[i].pal_power_mgmt_info_s.power_consumption; 760 min_power_state = i; 761 } 762 763 while (1) 764 ia64_pal_halt(min_power_state); 765 } 766 767 void machine_shutdown(void) 768 { 769 #ifdef CONFIG_HOTPLUG_CPU 770 int cpu; 771 772 for_each_online_cpu(cpu) { 773 if (cpu != smp_processor_id()) 774 cpu_down(cpu); 775 } 776 #endif 777 #ifdef CONFIG_KEXEC 778 kexec_disable_iosapic(); 779 #endif 780 } 781 782 void 783 machine_restart (char *restart_cmd) 784 { 785 (void) notify_die(DIE_MACHINE_RESTART, restart_cmd, NULL, 0, 0, 0); 786 (*efi.reset_system)(EFI_RESET_WARM, 0, 0, NULL); 787 } 788 789 void 790 machine_halt (void) 791 { 792 (void) notify_die(DIE_MACHINE_HALT, "", NULL, 0, 0, 0); 793 cpu_halt(); 794 } 795 796 void 797 machine_power_off (void) 798 { 799 if (pm_power_off) 800 pm_power_off(); 801 machine_halt(); 802 } 803 804