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 #include <linux/rcupdate.h>
33
34 #include <asm/cpu.h>
35 #include <asm/delay.h>
36 #include <asm/elf.h>
37 #include <asm/irq.h>
38 #include <asm/kexec.h>
39 #include <asm/pgalloc.h>
40 #include <asm/processor.h>
41 #include <asm/sal.h>
42 #include <asm/switch_to.h>
43 #include <asm/tlbflush.h>
44 #include <asm/uaccess.h>
45 #include <asm/unwind.h>
46 #include <asm/user.h>
47
48 #include "entry.h"
49
50 #ifdef CONFIG_PERFMON
51 # include <asm/perfmon.h>
52 #endif
53
54 #include "sigframe.h"
55
56 void (*ia64_mark_idle)(int);
57
58 unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE;
59 EXPORT_SYMBOL(boot_option_idle_override);
60 void (*pm_power_off) (void);
61 EXPORT_SYMBOL(pm_power_off);
62
63 void
ia64_do_show_stack(struct unw_frame_info * info,void * arg)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
show_stack(struct task_struct * task,unsigned long * sp)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
show_regs(struct pt_regs * regs)99 show_regs (struct pt_regs *regs)
100 {
101 unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri;
102
103 print_modules();
104 printk("\n");
105 show_regs_print_info(KERN_DEFAULT);
106 printk("psr : %016lx ifs : %016lx ip : [<%016lx>] %s (%s)\n",
107 regs->cr_ipsr, regs->cr_ifs, ip, print_tainted(),
108 init_utsname()->release);
109 print_symbol("ip is at %s\n", ip);
110 printk("unat: %016lx pfs : %016lx rsc : %016lx\n",
111 regs->ar_unat, regs->ar_pfs, regs->ar_rsc);
112 printk("rnat: %016lx bsps: %016lx pr : %016lx\n",
113 regs->ar_rnat, regs->ar_bspstore, regs->pr);
114 printk("ldrs: %016lx ccv : %016lx fpsr: %016lx\n",
115 regs->loadrs, regs->ar_ccv, regs->ar_fpsr);
116 printk("csd : %016lx ssd : %016lx\n", regs->ar_csd, regs->ar_ssd);
117 printk("b0 : %016lx b6 : %016lx b7 : %016lx\n", regs->b0, regs->b6, regs->b7);
118 printk("f6 : %05lx%016lx f7 : %05lx%016lx\n",
119 regs->f6.u.bits[1], regs->f6.u.bits[0],
120 regs->f7.u.bits[1], regs->f7.u.bits[0]);
121 printk("f8 : %05lx%016lx f9 : %05lx%016lx\n",
122 regs->f8.u.bits[1], regs->f8.u.bits[0],
123 regs->f9.u.bits[1], regs->f9.u.bits[0]);
124 printk("f10 : %05lx%016lx f11 : %05lx%016lx\n",
125 regs->f10.u.bits[1], regs->f10.u.bits[0],
126 regs->f11.u.bits[1], regs->f11.u.bits[0]);
127
128 printk("r1 : %016lx r2 : %016lx r3 : %016lx\n", regs->r1, regs->r2, regs->r3);
129 printk("r8 : %016lx r9 : %016lx r10 : %016lx\n", regs->r8, regs->r9, regs->r10);
130 printk("r11 : %016lx r12 : %016lx r13 : %016lx\n", regs->r11, regs->r12, regs->r13);
131 printk("r14 : %016lx r15 : %016lx r16 : %016lx\n", regs->r14, regs->r15, regs->r16);
132 printk("r17 : %016lx r18 : %016lx r19 : %016lx\n", regs->r17, regs->r18, regs->r19);
133 printk("r20 : %016lx r21 : %016lx r22 : %016lx\n", regs->r20, regs->r21, regs->r22);
134 printk("r23 : %016lx r24 : %016lx r25 : %016lx\n", regs->r23, regs->r24, regs->r25);
135 printk("r26 : %016lx r27 : %016lx r28 : %016lx\n", regs->r26, regs->r27, regs->r28);
136 printk("r29 : %016lx r30 : %016lx r31 : %016lx\n", regs->r29, regs->r30, regs->r31);
137
138 if (user_mode(regs)) {
139 /* print the stacked registers */
140 unsigned long val, *bsp, ndirty;
141 int i, sof, is_nat = 0;
142
143 sof = regs->cr_ifs & 0x7f; /* size of frame */
144 ndirty = (regs->loadrs >> 19);
145 bsp = ia64_rse_skip_regs((unsigned long *) regs->ar_bspstore, ndirty);
146 for (i = 0; i < sof; ++i) {
147 get_user(val, (unsigned long __user *) ia64_rse_skip_regs(bsp, i));
148 printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val,
149 ((i == sof - 1) || (i % 3) == 2) ? "\n" : " ");
150 }
151 } else
152 show_stack(NULL, NULL);
153 }
154
155 /* local support for deprecated console_print */
156 void
console_print(const char * s)157 console_print(const char *s)
158 {
159 printk(KERN_EMERG "%s", s);
160 }
161
162 void
do_notify_resume_user(sigset_t * unused,struct sigscratch * scr,long in_syscall)163 do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall)
164 {
165 if (fsys_mode(current, &scr->pt)) {
166 /*
167 * defer signal-handling etc. until we return to
168 * privilege-level 0.
169 */
170 if (!ia64_psr(&scr->pt)->lp)
171 ia64_psr(&scr->pt)->lp = 1;
172 return;
173 }
174
175 #ifdef CONFIG_PERFMON
176 if (current->thread.pfm_needs_checking)
177 /*
178 * Note: pfm_handle_work() allow us to call it with interrupts
179 * disabled, and may enable interrupts within the function.
180 */
181 pfm_handle_work();
182 #endif
183
184 /* deal with pending signal delivery */
185 if (test_thread_flag(TIF_SIGPENDING)) {
186 local_irq_enable(); /* force interrupt enable */
187 ia64_do_signal(scr, in_syscall);
188 }
189
190 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
191 local_irq_enable(); /* force interrupt enable */
192 tracehook_notify_resume(&scr->pt);
193 }
194
195 /* copy user rbs to kernel rbs */
196 if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) {
197 local_irq_enable(); /* force interrupt enable */
198 ia64_sync_krbs();
199 }
200
201 local_irq_disable(); /* force interrupt disable */
202 }
203
nohalt_setup(char * str)204 static int __init nohalt_setup(char * str)
205 {
206 cpu_idle_poll_ctrl(true);
207 return 1;
208 }
209 __setup("nohalt", nohalt_setup);
210
211 #ifdef CONFIG_HOTPLUG_CPU
212 /* We don't actually take CPU down, just spin without interrupts. */
play_dead(void)213 static inline void play_dead(void)
214 {
215 unsigned int this_cpu = smp_processor_id();
216
217 /* Ack it */
218 __this_cpu_write(cpu_state, CPU_DEAD);
219
220 max_xtp();
221 local_irq_disable();
222 idle_task_exit();
223 ia64_jump_to_sal(&sal_boot_rendez_state[this_cpu]);
224 /*
225 * The above is a point of no-return, the processor is
226 * expected to be in SAL loop now.
227 */
228 BUG();
229 }
230 #else
play_dead(void)231 static inline void play_dead(void)
232 {
233 BUG();
234 }
235 #endif /* CONFIG_HOTPLUG_CPU */
236
arch_cpu_idle_dead(void)237 void arch_cpu_idle_dead(void)
238 {
239 play_dead();
240 }
241
arch_cpu_idle(void)242 void arch_cpu_idle(void)
243 {
244 void (*mark_idle)(int) = ia64_mark_idle;
245
246 #ifdef CONFIG_SMP
247 min_xtp();
248 #endif
249 rmb();
250 if (mark_idle)
251 (*mark_idle)(1);
252
253 safe_halt();
254
255 if (mark_idle)
256 (*mark_idle)(0);
257 #ifdef CONFIG_SMP
258 normal_xtp();
259 #endif
260 }
261
262 void
ia64_save_extra(struct task_struct * task)263 ia64_save_extra (struct task_struct *task)
264 {
265 #ifdef CONFIG_PERFMON
266 unsigned long info;
267 #endif
268
269 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
270 ia64_save_debug_regs(&task->thread.dbr[0]);
271
272 #ifdef CONFIG_PERFMON
273 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
274 pfm_save_regs(task);
275
276 info = __this_cpu_read(pfm_syst_info);
277 if (info & PFM_CPUINFO_SYST_WIDE)
278 pfm_syst_wide_update_task(task, info, 0);
279 #endif
280 }
281
282 void
ia64_load_extra(struct task_struct * task)283 ia64_load_extra (struct task_struct *task)
284 {
285 #ifdef CONFIG_PERFMON
286 unsigned long info;
287 #endif
288
289 if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
290 ia64_load_debug_regs(&task->thread.dbr[0]);
291
292 #ifdef CONFIG_PERFMON
293 if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
294 pfm_load_regs(task);
295
296 info = __this_cpu_read(pfm_syst_info);
297 if (info & PFM_CPUINFO_SYST_WIDE)
298 pfm_syst_wide_update_task(task, info, 1);
299 #endif
300 }
301
302 /*
303 * Copy the state of an ia-64 thread.
304 *
305 * We get here through the following call chain:
306 *
307 * from user-level: from kernel:
308 *
309 * <clone syscall> <some kernel call frames>
310 * sys_clone :
311 * do_fork do_fork
312 * copy_thread copy_thread
313 *
314 * This means that the stack layout is as follows:
315 *
316 * +---------------------+ (highest addr)
317 * | struct pt_regs |
318 * +---------------------+
319 * | struct switch_stack |
320 * +---------------------+
321 * | |
322 * | memory stack |
323 * | | <-- sp (lowest addr)
324 * +---------------------+
325 *
326 * Observe that we copy the unat values that are in pt_regs and switch_stack. Spilling an
327 * integer to address X causes bit N in ar.unat to be set to the NaT bit of the register,
328 * with N=(X & 0x1ff)/8. Thus, copying the unat value preserves the NaT bits ONLY if the
329 * pt_regs structure in the parent is congruent to that of the child, modulo 512. Since
330 * the stack is page aligned and the page size is at least 4KB, this is always the case,
331 * so there is nothing to worry about.
332 */
333 int
copy_thread(unsigned long clone_flags,unsigned long user_stack_base,unsigned long user_stack_size,struct task_struct * p)334 copy_thread(unsigned long clone_flags,
335 unsigned long user_stack_base, unsigned long user_stack_size,
336 struct task_struct *p)
337 {
338 extern char ia64_ret_from_clone;
339 struct switch_stack *child_stack, *stack;
340 unsigned long rbs, child_rbs, rbs_size;
341 struct pt_regs *child_ptregs;
342 struct pt_regs *regs = current_pt_regs();
343 int retval = 0;
344
345 child_ptregs = (struct pt_regs *) ((unsigned long) p + IA64_STK_OFFSET) - 1;
346 child_stack = (struct switch_stack *) child_ptregs - 1;
347
348 rbs = (unsigned long) current + IA64_RBS_OFFSET;
349 child_rbs = (unsigned long) p + IA64_RBS_OFFSET;
350
351 /* copy parts of thread_struct: */
352 p->thread.ksp = (unsigned long) child_stack - 16;
353
354 /*
355 * NOTE: The calling convention considers all floating point
356 * registers in the high partition (fph) to be scratch. Since
357 * the only way to get to this point is through a system call,
358 * we know that the values in fph are all dead. Hence, there
359 * is no need to inherit the fph state from the parent to the
360 * child and all we have to do is to make sure that
361 * IA64_THREAD_FPH_VALID is cleared in the child.
362 *
363 * XXX We could push this optimization a bit further by
364 * clearing IA64_THREAD_FPH_VALID on ANY system call.
365 * However, it's not clear this is worth doing. Also, it
366 * would be a slight deviation from the normal Linux system
367 * call behavior where scratch registers are preserved across
368 * system calls (unless used by the system call itself).
369 */
370 # define THREAD_FLAGS_TO_CLEAR (IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID \
371 | IA64_THREAD_PM_VALID)
372 # define THREAD_FLAGS_TO_SET 0
373 p->thread.flags = ((current->thread.flags & ~THREAD_FLAGS_TO_CLEAR)
374 | THREAD_FLAGS_TO_SET);
375
376 ia64_drop_fpu(p); /* don't pick up stale state from a CPU's fph */
377
378 if (unlikely(p->flags & PF_KTHREAD)) {
379 if (unlikely(!user_stack_base)) {
380 /* fork_idle() called us */
381 return 0;
382 }
383 memset(child_stack, 0, sizeof(*child_ptregs) + sizeof(*child_stack));
384 child_stack->r4 = user_stack_base; /* payload */
385 child_stack->r5 = user_stack_size; /* argument */
386 /*
387 * Preserve PSR bits, except for bits 32-34 and 37-45,
388 * which we can't read.
389 */
390 child_ptregs->cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN;
391 /* mark as valid, empty frame */
392 child_ptregs->cr_ifs = 1UL << 63;
393 child_stack->ar_fpsr = child_ptregs->ar_fpsr
394 = ia64_getreg(_IA64_REG_AR_FPSR);
395 child_stack->pr = (1 << PRED_KERNEL_STACK);
396 child_stack->ar_bspstore = child_rbs;
397 child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
398
399 /* stop some PSR bits from being inherited.
400 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve()
401 * therefore we must specify them explicitly here and not include them in
402 * IA64_PSR_BITS_TO_CLEAR.
403 */
404 child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET)
405 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP));
406
407 return 0;
408 }
409 stack = ((struct switch_stack *) regs) - 1;
410 /* copy parent's switch_stack & pt_regs to child: */
411 memcpy(child_stack, stack, sizeof(*child_ptregs) + sizeof(*child_stack));
412
413 /* copy the parent's register backing store to the child: */
414 rbs_size = stack->ar_bspstore - rbs;
415 memcpy((void *) child_rbs, (void *) rbs, rbs_size);
416 if (clone_flags & CLONE_SETTLS)
417 child_ptregs->r13 = regs->r16; /* see sys_clone2() in entry.S */
418 if (user_stack_base) {
419 child_ptregs->r12 = user_stack_base + user_stack_size - 16;
420 child_ptregs->ar_bspstore = user_stack_base;
421 child_ptregs->ar_rnat = 0;
422 child_ptregs->loadrs = 0;
423 }
424 child_stack->ar_bspstore = child_rbs + rbs_size;
425 child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
426
427 /* stop some PSR bits from being inherited.
428 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve()
429 * therefore we must specify them explicitly here and not include them in
430 * IA64_PSR_BITS_TO_CLEAR.
431 */
432 child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET)
433 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP));
434
435 #ifdef CONFIG_PERFMON
436 if (current->thread.pfm_context)
437 pfm_inherit(p, child_ptregs);
438 #endif
439 return retval;
440 }
441
442 static void
do_copy_task_regs(struct task_struct * task,struct unw_frame_info * info,void * arg)443 do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg)
444 {
445 unsigned long mask, sp, nat_bits = 0, ar_rnat, urbs_end, cfm;
446 unsigned long uninitialized_var(ip); /* GCC be quiet */
447 elf_greg_t *dst = arg;
448 struct pt_regs *pt;
449 char nat;
450 int i;
451
452 memset(dst, 0, sizeof(elf_gregset_t)); /* don't leak any kernel bits to user-level */
453
454 if (unw_unwind_to_user(info) < 0)
455 return;
456
457 unw_get_sp(info, &sp);
458 pt = (struct pt_regs *) (sp + 16);
459
460 urbs_end = ia64_get_user_rbs_end(task, pt, &cfm);
461
462 if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0)
463 return;
464
465 ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end),
466 &ar_rnat);
467
468 /*
469 * coredump format:
470 * r0-r31
471 * NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
472 * predicate registers (p0-p63)
473 * b0-b7
474 * ip cfm user-mask
475 * ar.rsc ar.bsp ar.bspstore ar.rnat
476 * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
477 */
478
479 /* r0 is zero */
480 for (i = 1, mask = (1UL << i); i < 32; ++i) {
481 unw_get_gr(info, i, &dst[i], &nat);
482 if (nat)
483 nat_bits |= mask;
484 mask <<= 1;
485 }
486 dst[32] = nat_bits;
487 unw_get_pr(info, &dst[33]);
488
489 for (i = 0; i < 8; ++i)
490 unw_get_br(info, i, &dst[34 + i]);
491
492 unw_get_rp(info, &ip);
493 dst[42] = ip + ia64_psr(pt)->ri;
494 dst[43] = cfm;
495 dst[44] = pt->cr_ipsr & IA64_PSR_UM;
496
497 unw_get_ar(info, UNW_AR_RSC, &dst[45]);
498 /*
499 * For bsp and bspstore, unw_get_ar() would return the kernel
500 * addresses, but we need the user-level addresses instead:
501 */
502 dst[46] = urbs_end; /* note: by convention PT_AR_BSP points to the end of the urbs! */
503 dst[47] = pt->ar_bspstore;
504 dst[48] = ar_rnat;
505 unw_get_ar(info, UNW_AR_CCV, &dst[49]);
506 unw_get_ar(info, UNW_AR_UNAT, &dst[50]);
507 unw_get_ar(info, UNW_AR_FPSR, &dst[51]);
508 dst[52] = pt->ar_pfs; /* UNW_AR_PFS is == to pt->cr_ifs for interrupt frames */
509 unw_get_ar(info, UNW_AR_LC, &dst[53]);
510 unw_get_ar(info, UNW_AR_EC, &dst[54]);
511 unw_get_ar(info, UNW_AR_CSD, &dst[55]);
512 unw_get_ar(info, UNW_AR_SSD, &dst[56]);
513 }
514
515 void
do_dump_task_fpu(struct task_struct * task,struct unw_frame_info * info,void * arg)516 do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg)
517 {
518 elf_fpreg_t *dst = arg;
519 int i;
520
521 memset(dst, 0, sizeof(elf_fpregset_t)); /* don't leak any "random" bits */
522
523 if (unw_unwind_to_user(info) < 0)
524 return;
525
526 /* f0 is 0.0, f1 is 1.0 */
527
528 for (i = 2; i < 32; ++i)
529 unw_get_fr(info, i, dst + i);
530
531 ia64_flush_fph(task);
532 if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0)
533 memcpy(dst + 32, task->thread.fph, 96*16);
534 }
535
536 void
do_copy_regs(struct unw_frame_info * info,void * arg)537 do_copy_regs (struct unw_frame_info *info, void *arg)
538 {
539 do_copy_task_regs(current, info, arg);
540 }
541
542 void
do_dump_fpu(struct unw_frame_info * info,void * arg)543 do_dump_fpu (struct unw_frame_info *info, void *arg)
544 {
545 do_dump_task_fpu(current, info, arg);
546 }
547
548 void
ia64_elf_core_copy_regs(struct pt_regs * pt,elf_gregset_t dst)549 ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst)
550 {
551 unw_init_running(do_copy_regs, dst);
552 }
553
554 int
dump_fpu(struct pt_regs * pt,elf_fpregset_t dst)555 dump_fpu (struct pt_regs *pt, elf_fpregset_t dst)
556 {
557 unw_init_running(do_dump_fpu, dst);
558 return 1; /* f0-f31 are always valid so we always return 1 */
559 }
560
561 /*
562 * Flush thread state. This is called when a thread does an execve().
563 */
564 void
flush_thread(void)565 flush_thread (void)
566 {
567 /* drop floating-point and debug-register state if it exists: */
568 current->thread.flags &= ~(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID);
569 ia64_drop_fpu(current);
570 }
571
572 /*
573 * Clean up state associated with a thread. This is called when
574 * the thread calls exit().
575 */
576 void
exit_thread(struct task_struct * tsk)577 exit_thread (struct task_struct *tsk)
578 {
579
580 ia64_drop_fpu(tsk);
581 #ifdef CONFIG_PERFMON
582 /* if needed, stop monitoring and flush state to perfmon context */
583 if (tsk->thread.pfm_context)
584 pfm_exit_thread(tsk);
585
586 /* free debug register resources */
587 if (tsk->thread.flags & IA64_THREAD_DBG_VALID)
588 pfm_release_debug_registers(tsk);
589 #endif
590 }
591
592 unsigned long
get_wchan(struct task_struct * p)593 get_wchan (struct task_struct *p)
594 {
595 struct unw_frame_info info;
596 unsigned long ip;
597 int count = 0;
598
599 if (!p || p == current || p->state == TASK_RUNNING)
600 return 0;
601
602 /*
603 * Note: p may not be a blocked task (it could be current or
604 * another process running on some other CPU. Rather than
605 * trying to determine if p is really blocked, we just assume
606 * it's blocked and rely on the unwind routines to fail
607 * gracefully if the process wasn't really blocked after all.
608 * --davidm 99/12/15
609 */
610 unw_init_from_blocked_task(&info, p);
611 do {
612 if (p->state == TASK_RUNNING)
613 return 0;
614 if (unw_unwind(&info) < 0)
615 return 0;
616 unw_get_ip(&info, &ip);
617 if (!in_sched_functions(ip))
618 return ip;
619 } while (count++ < 16);
620 return 0;
621 }
622
623 void
cpu_halt(void)624 cpu_halt (void)
625 {
626 pal_power_mgmt_info_u_t power_info[8];
627 unsigned long min_power;
628 int i, min_power_state;
629
630 if (ia64_pal_halt_info(power_info) != 0)
631 return;
632
633 min_power_state = 0;
634 min_power = power_info[0].pal_power_mgmt_info_s.power_consumption;
635 for (i = 1; i < 8; ++i)
636 if (power_info[i].pal_power_mgmt_info_s.im
637 && power_info[i].pal_power_mgmt_info_s.power_consumption < min_power) {
638 min_power = power_info[i].pal_power_mgmt_info_s.power_consumption;
639 min_power_state = i;
640 }
641
642 while (1)
643 ia64_pal_halt(min_power_state);
644 }
645
machine_shutdown(void)646 void machine_shutdown(void)
647 {
648 #ifdef CONFIG_HOTPLUG_CPU
649 int cpu;
650
651 for_each_online_cpu(cpu) {
652 if (cpu != smp_processor_id())
653 cpu_down(cpu);
654 }
655 #endif
656 #ifdef CONFIG_KEXEC
657 kexec_disable_iosapic();
658 #endif
659 }
660
661 void
machine_restart(char * restart_cmd)662 machine_restart (char *restart_cmd)
663 {
664 (void) notify_die(DIE_MACHINE_RESTART, restart_cmd, NULL, 0, 0, 0);
665 efi_reboot(REBOOT_WARM, NULL);
666 }
667
668 void
machine_halt(void)669 machine_halt (void)
670 {
671 (void) notify_die(DIE_MACHINE_HALT, "", NULL, 0, 0, 0);
672 cpu_halt();
673 }
674
675 void
machine_power_off(void)676 machine_power_off (void)
677 {
678 if (pm_power_off)
679 pm_power_off();
680 machine_halt();
681 }
682
683