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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Architecture-specific setup.
  4 *
  5 * Copyright (C) 1998-2003 Hewlett-Packard Co
  6 *	David Mosberger-Tang <davidm@hpl.hp.com>
  7 * 04/11/17 Ashok Raj	<ashok.raj@intel.com> Added CPU Hotplug Support
  8 *
  9 * 2005-10-07 Keith Owens <kaos@sgi.com>
 10 *	      Add notify_die() hooks.
 11 */
 12#include <linux/cpu.h>
 13#include <linux/pm.h>
 14#include <linux/elf.h>
 15#include <linux/errno.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/sched/debug.h>
 24#include <linux/sched/hotplug.h>
 25#include <linux/sched/task.h>
 26#include <linux/sched/task_stack.h>
 27#include <linux/stddef.h>
 28#include <linux/thread_info.h>
 29#include <linux/unistd.h>
 30#include <linux/efi.h>
 31#include <linux/interrupt.h>
 32#include <linux/delay.h>
 33#include <linux/kdebug.h>
 34#include <linux/utsname.h>
 35#include <linux/tracehook.h>
 36#include <linux/rcupdate.h>
 37
 38#include <asm/cpu.h>
 39#include <asm/delay.h>
 40#include <asm/elf.h>
 41#include <asm/irq.h>
 42#include <asm/kexec.h>
 43#include <asm/pgalloc.h>
 44#include <asm/processor.h>
 45#include <asm/sal.h>
 46#include <asm/switch_to.h>
 47#include <asm/tlbflush.h>
 48#include <linux/uaccess.h>
 49#include <asm/unwind.h>
 50#include <asm/user.h>
 51
 52#include "entry.h"
 53
 54#ifdef CONFIG_PERFMON
 55# include <asm/perfmon.h>
 56#endif
 57
 58#include "sigframe.h"
 59
 60void (*ia64_mark_idle)(int);
 61
 62unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE;
 63EXPORT_SYMBOL(boot_option_idle_override);
 64void (*pm_power_off) (void);
 65EXPORT_SYMBOL(pm_power_off);
 66
 67void
 68ia64_do_show_stack (struct unw_frame_info *info, void *arg)
 69{
 70	unsigned long ip, sp, bsp;
 
 71
 72	printk("\nCall Trace:\n");
 73	do {
 74		unw_get_ip(info, &ip);
 75		if (ip == 0)
 76			break;
 77
 78		unw_get_sp(info, &sp);
 79		unw_get_bsp(info, &bsp);
 80		printk(" [<%016lx>] %pS\n"
 
 81			 "                                sp=%016lx bsp=%016lx\n",
 82			 ip, (void *)ip, sp, bsp);
 
 83	} while (unw_unwind(info) >= 0);
 84}
 85
 86void
 87show_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
 99void
100show_regs (struct pt_regs *regs)
101{
102	unsigned long ip = regs->cr_iip + ia64_psr(regs)->ri;
103
104	print_modules();
105	printk("\n");
106	show_regs_print_info(KERN_DEFAULT);
107	printk("psr : %016lx ifs : %016lx ip  : [<%016lx>]    %s (%s)\n",
108	       regs->cr_ipsr, regs->cr_ifs, ip, print_tainted(),
109	       init_utsname()->release);
110	printk("ip is at %pS\n", (void *)ip);
111	printk("unat: %016lx pfs : %016lx rsc : %016lx\n",
112	       regs->ar_unat, regs->ar_pfs, regs->ar_rsc);
113	printk("rnat: %016lx bsps: %016lx pr  : %016lx\n",
114	       regs->ar_rnat, regs->ar_bspstore, regs->pr);
115	printk("ldrs: %016lx ccv : %016lx fpsr: %016lx\n",
116	       regs->loadrs, regs->ar_ccv, regs->ar_fpsr);
117	printk("csd : %016lx ssd : %016lx\n", regs->ar_csd, regs->ar_ssd);
118	printk("b0  : %016lx b6  : %016lx b7  : %016lx\n", regs->b0, regs->b6, regs->b7);
119	printk("f6  : %05lx%016lx f7  : %05lx%016lx\n",
120	       regs->f6.u.bits[1], regs->f6.u.bits[0],
121	       regs->f7.u.bits[1], regs->f7.u.bits[0]);
122	printk("f8  : %05lx%016lx f9  : %05lx%016lx\n",
123	       regs->f8.u.bits[1], regs->f8.u.bits[0],
124	       regs->f9.u.bits[1], regs->f9.u.bits[0]);
125	printk("f10 : %05lx%016lx f11 : %05lx%016lx\n",
126	       regs->f10.u.bits[1], regs->f10.u.bits[0],
127	       regs->f11.u.bits[1], regs->f11.u.bits[0]);
128
129	printk("r1  : %016lx r2  : %016lx r3  : %016lx\n", regs->r1, regs->r2, regs->r3);
130	printk("r8  : %016lx r9  : %016lx r10 : %016lx\n", regs->r8, regs->r9, regs->r10);
131	printk("r11 : %016lx r12 : %016lx r13 : %016lx\n", regs->r11, regs->r12, regs->r13);
132	printk("r14 : %016lx r15 : %016lx r16 : %016lx\n", regs->r14, regs->r15, regs->r16);
133	printk("r17 : %016lx r18 : %016lx r19 : %016lx\n", regs->r17, regs->r18, regs->r19);
134	printk("r20 : %016lx r21 : %016lx r22 : %016lx\n", regs->r20, regs->r21, regs->r22);
135	printk("r23 : %016lx r24 : %016lx r25 : %016lx\n", regs->r23, regs->r24, regs->r25);
136	printk("r26 : %016lx r27 : %016lx r28 : %016lx\n", regs->r26, regs->r27, regs->r28);
137	printk("r29 : %016lx r30 : %016lx r31 : %016lx\n", regs->r29, regs->r30, regs->r31);
138
139	if (user_mode(regs)) {
140		/* print the stacked registers */
141		unsigned long val, *bsp, ndirty;
142		int i, sof, is_nat = 0;
143
144		sof = regs->cr_ifs & 0x7f;	/* size of frame */
145		ndirty = (regs->loadrs >> 19);
146		bsp = ia64_rse_skip_regs((unsigned long *) regs->ar_bspstore, ndirty);
147		for (i = 0; i < sof; ++i) {
148			get_user(val, (unsigned long __user *) ia64_rse_skip_regs(bsp, i));
149			printk("r%-3u:%c%016lx%s", 32 + i, is_nat ? '*' : ' ', val,
150			       ((i == sof - 1) || (i % 3) == 2) ? "\n" : " ");
151		}
152	} else
153		show_stack(NULL, NULL);
154}
155
156/* local support for deprecated console_print */
157void
158console_print(const char *s)
159{
160	printk(KERN_EMERG "%s", s);
161}
162
163void
164do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall)
165{
166	if (fsys_mode(current, &scr->pt)) {
167		/*
168		 * defer signal-handling etc. until we return to
169		 * privilege-level 0.
170		 */
171		if (!ia64_psr(&scr->pt)->lp)
172			ia64_psr(&scr->pt)->lp = 1;
173		return;
174	}
175
176#ifdef CONFIG_PERFMON
177	if (current->thread.pfm_needs_checking)
178		/*
179		 * Note: pfm_handle_work() allow us to call it with interrupts
180		 * disabled, and may enable interrupts within the function.
181		 */
182		pfm_handle_work();
183#endif
184
185	/* deal with pending signal delivery */
186	if (test_thread_flag(TIF_SIGPENDING)) {
187		local_irq_enable();	/* force interrupt enable */
188		ia64_do_signal(scr, in_syscall);
189	}
190
191	if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) {
192		local_irq_enable();	/* force interrupt enable */
193		tracehook_notify_resume(&scr->pt);
194	}
195
196	/* copy user rbs to kernel rbs */
197	if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) {
198		local_irq_enable();	/* force interrupt enable */
199		ia64_sync_krbs();
200	}
201
202	local_irq_disable();	/* force interrupt disable */
203}
204
205static int __init nohalt_setup(char * str)
206{
207	cpu_idle_poll_ctrl(true);
208	return 1;
209}
210__setup("nohalt", nohalt_setup);
211
212#ifdef CONFIG_HOTPLUG_CPU
213/* We don't actually take CPU down, just spin without interrupts. */
214static inline void play_dead(void)
215{
216	unsigned int this_cpu = smp_processor_id();
217
218	/* Ack it */
219	__this_cpu_write(cpu_state, CPU_DEAD);
220
221	max_xtp();
222	local_irq_disable();
223	idle_task_exit();
224	ia64_jump_to_sal(&sal_boot_rendez_state[this_cpu]);
225	/*
226	 * The above is a point of no-return, the processor is
227	 * expected to be in SAL loop now.
228	 */
229	BUG();
230}
231#else
232static inline void play_dead(void)
233{
234	BUG();
235}
236#endif /* CONFIG_HOTPLUG_CPU */
237
238void arch_cpu_idle_dead(void)
239{
240	play_dead();
241}
242
243void arch_cpu_idle(void)
244{
245	void (*mark_idle)(int) = ia64_mark_idle;
246
247#ifdef CONFIG_SMP
248	min_xtp();
249#endif
250	rmb();
251	if (mark_idle)
252		(*mark_idle)(1);
253
254	safe_halt();
255
256	if (mark_idle)
257		(*mark_idle)(0);
258#ifdef CONFIG_SMP
259	normal_xtp();
260#endif
261}
262
263void
264ia64_save_extra (struct task_struct *task)
265{
266#ifdef CONFIG_PERFMON
267	unsigned long info;
268#endif
269
270	if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
271		ia64_save_debug_regs(&task->thread.dbr[0]);
272
273#ifdef CONFIG_PERFMON
274	if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
275		pfm_save_regs(task);
276
277	info = __this_cpu_read(pfm_syst_info);
278	if (info & PFM_CPUINFO_SYST_WIDE)
279		pfm_syst_wide_update_task(task, info, 0);
280#endif
281}
282
283void
284ia64_load_extra (struct task_struct *task)
285{
286#ifdef CONFIG_PERFMON
287	unsigned long info;
288#endif
289
290	if ((task->thread.flags & IA64_THREAD_DBG_VALID) != 0)
291		ia64_load_debug_regs(&task->thread.dbr[0]);
292
293#ifdef CONFIG_PERFMON
294	if ((task->thread.flags & IA64_THREAD_PM_VALID) != 0)
295		pfm_load_regs(task);
296
297	info = __this_cpu_read(pfm_syst_info);
298	if (info & PFM_CPUINFO_SYST_WIDE) 
299		pfm_syst_wide_update_task(task, info, 1);
300#endif
301}
302
303/*
304 * Copy the state of an ia-64 thread.
305 *
306 * We get here through the following  call chain:
307 *
308 *	from user-level:	from kernel:
309 *
310 *	<clone syscall>	        <some kernel call frames>
311 *	sys_clone		   :
312 *	do_fork			do_fork
313 *	copy_thread		copy_thread
314 *
315 * This means that the stack layout is as follows:
316 *
317 *	+---------------------+ (highest addr)
318 *	|   struct pt_regs    |
319 *	+---------------------+
320 *	| struct switch_stack |
321 *	+---------------------+
322 *	|                     |
323 *	|    memory stack     |
324 *	|                     | <-- sp (lowest addr)
325 *	+---------------------+
326 *
327 * Observe that we copy the unat values that are in pt_regs and switch_stack.  Spilling an
328 * integer to address X causes bit N in ar.unat to be set to the NaT bit of the register,
329 * with N=(X & 0x1ff)/8.  Thus, copying the unat value preserves the NaT bits ONLY if the
330 * pt_regs structure in the parent is congruent to that of the child, modulo 512.  Since
331 * the stack is page aligned and the page size is at least 4KB, this is always the case,
332 * so there is nothing to worry about.
333 */
334int
335copy_thread(unsigned long clone_flags,
336	     unsigned long user_stack_base, unsigned long user_stack_size,
337	     struct task_struct *p)
338{
339	extern char ia64_ret_from_clone;
340	struct switch_stack *child_stack, *stack;
341	unsigned long rbs, child_rbs, rbs_size;
342	struct pt_regs *child_ptregs;
343	struct pt_regs *regs = current_pt_regs();
344	int retval = 0;
345
346	child_ptregs = (struct pt_regs *) ((unsigned long) p + IA64_STK_OFFSET) - 1;
347	child_stack = (struct switch_stack *) child_ptregs - 1;
348
349	rbs = (unsigned long) current + IA64_RBS_OFFSET;
350	child_rbs = (unsigned long) p + IA64_RBS_OFFSET;
351
352	/* copy parts of thread_struct: */
353	p->thread.ksp = (unsigned long) child_stack - 16;
354
355	/*
356	 * NOTE: The calling convention considers all floating point
357	 * registers in the high partition (fph) to be scratch.  Since
358	 * the only way to get to this point is through a system call,
359	 * we know that the values in fph are all dead.  Hence, there
360	 * is no need to inherit the fph state from the parent to the
361	 * child and all we have to do is to make sure that
362	 * IA64_THREAD_FPH_VALID is cleared in the child.
363	 *
364	 * XXX We could push this optimization a bit further by
365	 * clearing IA64_THREAD_FPH_VALID on ANY system call.
366	 * However, it's not clear this is worth doing.  Also, it
367	 * would be a slight deviation from the normal Linux system
368	 * call behavior where scratch registers are preserved across
369	 * system calls (unless used by the system call itself).
370	 */
371#	define THREAD_FLAGS_TO_CLEAR	(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID \
372					 | IA64_THREAD_PM_VALID)
373#	define THREAD_FLAGS_TO_SET	0
374	p->thread.flags = ((current->thread.flags & ~THREAD_FLAGS_TO_CLEAR)
375			   | THREAD_FLAGS_TO_SET);
376
377	ia64_drop_fpu(p);	/* don't pick up stale state from a CPU's fph */
378
379	if (unlikely(p->flags & PF_KTHREAD)) {
380		if (unlikely(!user_stack_base)) {
381			/* fork_idle() called us */
382			return 0;
383		}
384		memset(child_stack, 0, sizeof(*child_ptregs) + sizeof(*child_stack));
385		child_stack->r4 = user_stack_base;	/* payload */
386		child_stack->r5 = user_stack_size;	/* argument */
387		/*
388		 * Preserve PSR bits, except for bits 32-34 and 37-45,
389		 * which we can't read.
390		 */
391		child_ptregs->cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN;
392		/* mark as valid, empty frame */
393		child_ptregs->cr_ifs = 1UL << 63;
394		child_stack->ar_fpsr = child_ptregs->ar_fpsr
395			= ia64_getreg(_IA64_REG_AR_FPSR);
396		child_stack->pr = (1 << PRED_KERNEL_STACK);
397		child_stack->ar_bspstore = child_rbs;
398		child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
399
400		/* stop some PSR bits from being inherited.
401		 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve()
402		 * therefore we must specify them explicitly here and not include them in
403		 * IA64_PSR_BITS_TO_CLEAR.
404		 */
405		child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET)
406				 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP));
407
408		return 0;
409	}
410	stack = ((struct switch_stack *) regs) - 1;
411	/* copy parent's switch_stack & pt_regs to child: */
412	memcpy(child_stack, stack, sizeof(*child_ptregs) + sizeof(*child_stack));
413
414	/* copy the parent's register backing store to the child: */
415	rbs_size = stack->ar_bspstore - rbs;
416	memcpy((void *) child_rbs, (void *) rbs, rbs_size);
417	if (clone_flags & CLONE_SETTLS)
418		child_ptregs->r13 = regs->r16;	/* see sys_clone2() in entry.S */
419	if (user_stack_base) {
420		child_ptregs->r12 = user_stack_base + user_stack_size - 16;
421		child_ptregs->ar_bspstore = user_stack_base;
422		child_ptregs->ar_rnat = 0;
423		child_ptregs->loadrs = 0;
424	}
425	child_stack->ar_bspstore = child_rbs + rbs_size;
426	child_stack->b0 = (unsigned long) &ia64_ret_from_clone;
427
428	/* stop some PSR bits from being inherited.
429	 * the psr.up/psr.pp bits must be cleared on fork but inherited on execve()
430	 * therefore we must specify them explicitly here and not include them in
431	 * IA64_PSR_BITS_TO_CLEAR.
432	 */
433	child_ptregs->cr_ipsr = ((child_ptregs->cr_ipsr | IA64_PSR_BITS_TO_SET)
434				 & ~(IA64_PSR_BITS_TO_CLEAR | IA64_PSR_PP | IA64_PSR_UP));
435
436#ifdef CONFIG_PERFMON
437	if (current->thread.pfm_context)
438		pfm_inherit(p, child_ptregs);
439#endif
440	return retval;
441}
442
443static void
444do_copy_task_regs (struct task_struct *task, struct unw_frame_info *info, void *arg)
445{
446	unsigned long mask, sp, nat_bits = 0, ar_rnat, urbs_end, cfm;
447	unsigned long uninitialized_var(ip);	/* GCC be quiet */
448	elf_greg_t *dst = arg;
449	struct pt_regs *pt;
450	char nat;
451	int i;
452
453	memset(dst, 0, sizeof(elf_gregset_t));	/* don't leak any kernel bits to user-level */
454
455	if (unw_unwind_to_user(info) < 0)
456		return;
457
458	unw_get_sp(info, &sp);
459	pt = (struct pt_regs *) (sp + 16);
460
461	urbs_end = ia64_get_user_rbs_end(task, pt, &cfm);
462
463	if (ia64_sync_user_rbs(task, info->sw, pt->ar_bspstore, urbs_end) < 0)
464		return;
465
466	ia64_peek(task, info->sw, urbs_end, (long) ia64_rse_rnat_addr((long *) urbs_end),
467		  &ar_rnat);
468
469	/*
470	 * coredump format:
471	 *	r0-r31
472	 *	NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
473	 *	predicate registers (p0-p63)
474	 *	b0-b7
475	 *	ip cfm user-mask
476	 *	ar.rsc ar.bsp ar.bspstore ar.rnat
477	 *	ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
478	 */
479
480	/* r0 is zero */
481	for (i = 1, mask = (1UL << i); i < 32; ++i) {
482		unw_get_gr(info, i, &dst[i], &nat);
483		if (nat)
484			nat_bits |= mask;
485		mask <<= 1;
486	}
487	dst[32] = nat_bits;
488	unw_get_pr(info, &dst[33]);
489
490	for (i = 0; i < 8; ++i)
491		unw_get_br(info, i, &dst[34 + i]);
492
493	unw_get_rp(info, &ip);
494	dst[42] = ip + ia64_psr(pt)->ri;
495	dst[43] = cfm;
496	dst[44] = pt->cr_ipsr & IA64_PSR_UM;
497
498	unw_get_ar(info, UNW_AR_RSC, &dst[45]);
499	/*
500	 * For bsp and bspstore, unw_get_ar() would return the kernel
501	 * addresses, but we need the user-level addresses instead:
502	 */
503	dst[46] = urbs_end;	/* note: by convention PT_AR_BSP points to the end of the urbs! */
504	dst[47] = pt->ar_bspstore;
505	dst[48] = ar_rnat;
506	unw_get_ar(info, UNW_AR_CCV, &dst[49]);
507	unw_get_ar(info, UNW_AR_UNAT, &dst[50]);
508	unw_get_ar(info, UNW_AR_FPSR, &dst[51]);
509	dst[52] = pt->ar_pfs;	/* UNW_AR_PFS is == to pt->cr_ifs for interrupt frames */
510	unw_get_ar(info, UNW_AR_LC, &dst[53]);
511	unw_get_ar(info, UNW_AR_EC, &dst[54]);
512	unw_get_ar(info, UNW_AR_CSD, &dst[55]);
513	unw_get_ar(info, UNW_AR_SSD, &dst[56]);
514}
515
516void
517do_dump_task_fpu (struct task_struct *task, struct unw_frame_info *info, void *arg)
518{
519	elf_fpreg_t *dst = arg;
520	int i;
521
522	memset(dst, 0, sizeof(elf_fpregset_t));	/* don't leak any "random" bits */
523
524	if (unw_unwind_to_user(info) < 0)
525		return;
526
527	/* f0 is 0.0, f1 is 1.0 */
528
529	for (i = 2; i < 32; ++i)
530		unw_get_fr(info, i, dst + i);
531
532	ia64_flush_fph(task);
533	if ((task->thread.flags & IA64_THREAD_FPH_VALID) != 0)
534		memcpy(dst + 32, task->thread.fph, 96*16);
535}
536
537void
538do_copy_regs (struct unw_frame_info *info, void *arg)
539{
540	do_copy_task_regs(current, info, arg);
541}
542
543void
544do_dump_fpu (struct unw_frame_info *info, void *arg)
545{
546	do_dump_task_fpu(current, info, arg);
547}
548
549void
550ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst)
551{
552	unw_init_running(do_copy_regs, dst);
553}
554
555int
556dump_fpu (struct pt_regs *pt, elf_fpregset_t dst)
557{
558	unw_init_running(do_dump_fpu, dst);
559	return 1;	/* f0-f31 are always valid so we always return 1 */
560}
561
562/*
563 * Flush thread state.  This is called when a thread does an execve().
564 */
565void
566flush_thread (void)
567{
568	/* drop floating-point and debug-register state if it exists: */
569	current->thread.flags &= ~(IA64_THREAD_FPH_VALID | IA64_THREAD_DBG_VALID);
570	ia64_drop_fpu(current);
571}
572
573/*
574 * Clean up state associated with a thread.  This is called when
575 * the thread calls exit().
576 */
577void
578exit_thread (struct task_struct *tsk)
579{
580
581	ia64_drop_fpu(tsk);
582#ifdef CONFIG_PERFMON
583       /* if needed, stop monitoring and flush state to perfmon context */
584	if (tsk->thread.pfm_context)
585		pfm_exit_thread(tsk);
586
587	/* free debug register resources */
588	if (tsk->thread.flags & IA64_THREAD_DBG_VALID)
589		pfm_release_debug_registers(tsk);
590#endif
591}
592
593unsigned long
594get_wchan (struct task_struct *p)
595{
596	struct unw_frame_info info;
597	unsigned long ip;
598	int count = 0;
599
600	if (!p || p == current || p->state == TASK_RUNNING)
601		return 0;
602
603	/*
604	 * Note: p may not be a blocked task (it could be current or
605	 * another process running on some other CPU.  Rather than
606	 * trying to determine if p is really blocked, we just assume
607	 * it's blocked and rely on the unwind routines to fail
608	 * gracefully if the process wasn't really blocked after all.
609	 * --davidm 99/12/15
610	 */
611	unw_init_from_blocked_task(&info, p);
612	do {
613		if (p->state == TASK_RUNNING)
614			return 0;
615		if (unw_unwind(&info) < 0)
616			return 0;
617		unw_get_ip(&info, &ip);
618		if (!in_sched_functions(ip))
619			return ip;
620	} while (count++ < 16);
621	return 0;
622}
623
624void
625cpu_halt (void)
626{
627	pal_power_mgmt_info_u_t power_info[8];
628	unsigned long min_power;
629	int i, min_power_state;
630
631	if (ia64_pal_halt_info(power_info) != 0)
632		return;
633
634	min_power_state = 0;
635	min_power = power_info[0].pal_power_mgmt_info_s.power_consumption;
636	for (i = 1; i < 8; ++i)
637		if (power_info[i].pal_power_mgmt_info_s.im
638		    && power_info[i].pal_power_mgmt_info_s.power_consumption < min_power) {
639			min_power = power_info[i].pal_power_mgmt_info_s.power_consumption;
640			min_power_state = i;
641		}
642
643	while (1)
644		ia64_pal_halt(min_power_state);
645}
646
647void machine_shutdown(void)
648{
649#ifdef CONFIG_HOTPLUG_CPU
650	int cpu;
651
652	for_each_online_cpu(cpu) {
653		if (cpu != smp_processor_id())
654			cpu_down(cpu);
655	}
656#endif
657#ifdef CONFIG_KEXEC
658	kexec_disable_iosapic();
659#endif
660}
661
662void
663machine_restart (char *restart_cmd)
664{
665	(void) notify_die(DIE_MACHINE_RESTART, restart_cmd, NULL, 0, 0, 0);
666	efi_reboot(REBOOT_WARM, NULL);
667}
668
669void
670machine_halt (void)
671{
672	(void) notify_die(DIE_MACHINE_HALT, "", NULL, 0, 0, 0);
673	cpu_halt();
674}
675
676void
677machine_power_off (void)
678{
679	if (pm_power_off)
680		pm_power_off();
681	machine_halt();
682}
683
v4.6
 
  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
 56void (*ia64_mark_idle)(int);
 57
 58unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE;
 59EXPORT_SYMBOL(boot_option_idle_override);
 60void (*pm_power_off) (void);
 61EXPORT_SYMBOL(pm_power_off);
 62
 63void
 64ia64_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
 85void
 86show_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
 98void
 99show_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 */
156void
157console_print(const char *s)
158{
159	printk(KERN_EMERG "%s", s);
160}
161
162void
163do_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
204static 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. */
213static 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
231static inline void play_dead(void)
232{
233	BUG();
234}
235#endif /* CONFIG_HOTPLUG_CPU */
236
237void arch_cpu_idle_dead(void)
238{
239	play_dead();
240}
241
242void 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
262void
263ia64_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
282void
283ia64_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 */
333int
334copy_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
442static void
443do_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
515void
516do_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
536void
537do_copy_regs (struct unw_frame_info *info, void *arg)
538{
539	do_copy_task_regs(current, info, arg);
540}
541
542void
543do_dump_fpu (struct unw_frame_info *info, void *arg)
544{
545	do_dump_task_fpu(current, info, arg);
546}
547
548void
549ia64_elf_core_copy_regs (struct pt_regs *pt, elf_gregset_t dst)
550{
551	unw_init_running(do_copy_regs, dst);
552}
553
554int
555dump_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 */
564void
565flush_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 current thread.  This is called when
574 * the thread calls exit().
575 */
576void
577exit_thread (void)
578{
579
580	ia64_drop_fpu(current);
581#ifdef CONFIG_PERFMON
582       /* if needed, stop monitoring and flush state to perfmon context */
583	if (current->thread.pfm_context)
584		pfm_exit_thread(current);
585
586	/* free debug register resources */
587	if (current->thread.flags & IA64_THREAD_DBG_VALID)
588		pfm_release_debug_registers(current);
589#endif
590}
591
592unsigned long
593get_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
623void
624cpu_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
646void 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
661void
662machine_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
668void
669machine_halt (void)
670{
671	(void) notify_die(DIE_MACHINE_HALT, "", NULL, 0, 0, 0);
672	cpu_halt();
673}
674
675void
676machine_power_off (void)
677{
678	if (pm_power_off)
679		pm_power_off();
680	machine_halt();
681}
682