xref: /openbmc/linux/arch/ia64/kernel/irq_ia64.c (revision 9cfc5c90)
1 /*
2  * linux/arch/ia64/kernel/irq_ia64.c
3  *
4  * Copyright (C) 1998-2001 Hewlett-Packard Co
5  *	Stephane Eranian <eranian@hpl.hp.com>
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  *
8  *  6/10/99: Updated to bring in sync with x86 version to facilitate
9  *	     support for SMP and different interrupt controllers.
10  *
11  * 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
12  *                      PCI to vector allocation routine.
13  * 04/14/2004 Ashok Raj <ashok.raj@intel.com>
14  *						Added CPU Hotplug handling for IPF.
15  */
16 
17 #include <linux/module.h>
18 
19 #include <linux/jiffies.h>
20 #include <linux/errno.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/ioport.h>
24 #include <linux/kernel_stat.h>
25 #include <linux/ptrace.h>
26 #include <linux/signal.h>
27 #include <linux/smp.h>
28 #include <linux/threads.h>
29 #include <linux/bitops.h>
30 #include <linux/irq.h>
31 #include <linux/ratelimit.h>
32 #include <linux/acpi.h>
33 #include <linux/sched.h>
34 
35 #include <asm/delay.h>
36 #include <asm/intrinsics.h>
37 #include <asm/io.h>
38 #include <asm/hw_irq.h>
39 #include <asm/machvec.h>
40 #include <asm/pgtable.h>
41 #include <asm/tlbflush.h>
42 
43 #ifdef CONFIG_PERFMON
44 # include <asm/perfmon.h>
45 #endif
46 
47 #define IRQ_DEBUG	0
48 
49 #define IRQ_VECTOR_UNASSIGNED	(0)
50 
51 #define IRQ_UNUSED		(0)
52 #define IRQ_USED		(1)
53 #define IRQ_RSVD		(2)
54 
55 /* These can be overridden in platform_irq_init */
56 int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
57 int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;
58 
59 /* default base addr of IPI table */
60 void __iomem *ipi_base_addr = ((void __iomem *)
61 			       (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));
62 
63 static cpumask_t vector_allocation_domain(int cpu);
64 
65 /*
66  * Legacy IRQ to IA-64 vector translation table.
67  */
68 __u8 isa_irq_to_vector_map[16] = {
69 	/* 8259 IRQ translation, first 16 entries */
70 	0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
71 	0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
72 };
73 EXPORT_SYMBOL(isa_irq_to_vector_map);
74 
75 DEFINE_SPINLOCK(vector_lock);
76 
77 struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
78 	[0 ... NR_IRQS - 1] = {
79 		.vector = IRQ_VECTOR_UNASSIGNED,
80 		.domain = CPU_MASK_NONE
81 	}
82 };
83 
84 DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = {
85 	[0 ... IA64_NUM_VECTORS - 1] = -1
86 };
87 
88 static cpumask_t vector_table[IA64_NUM_VECTORS] = {
89 	[0 ... IA64_NUM_VECTORS - 1] = CPU_MASK_NONE
90 };
91 
92 static int irq_status[NR_IRQS] = {
93 	[0 ... NR_IRQS -1] = IRQ_UNUSED
94 };
95 
96 static inline int find_unassigned_irq(void)
97 {
98 	int irq;
99 
100 	for (irq = IA64_FIRST_DEVICE_VECTOR; irq < NR_IRQS; irq++)
101 		if (irq_status[irq] == IRQ_UNUSED)
102 			return irq;
103 	return -ENOSPC;
104 }
105 
106 static inline int find_unassigned_vector(cpumask_t domain)
107 {
108 	cpumask_t mask;
109 	int pos, vector;
110 
111 	cpumask_and(&mask, &domain, cpu_online_mask);
112 	if (cpumask_empty(&mask))
113 		return -EINVAL;
114 
115 	for (pos = 0; pos < IA64_NUM_DEVICE_VECTORS; pos++) {
116 		vector = IA64_FIRST_DEVICE_VECTOR + pos;
117 		cpumask_and(&mask, &domain, &vector_table[vector]);
118 		if (!cpumask_empty(&mask))
119 			continue;
120 		return vector;
121 	}
122 	return -ENOSPC;
123 }
124 
125 static int __bind_irq_vector(int irq, int vector, cpumask_t domain)
126 {
127 	cpumask_t mask;
128 	int cpu;
129 	struct irq_cfg *cfg = &irq_cfg[irq];
130 
131 	BUG_ON((unsigned)irq >= NR_IRQS);
132 	BUG_ON((unsigned)vector >= IA64_NUM_VECTORS);
133 
134 	cpumask_and(&mask, &domain, cpu_online_mask);
135 	if (cpumask_empty(&mask))
136 		return -EINVAL;
137 	if ((cfg->vector == vector) && cpumask_equal(&cfg->domain, &domain))
138 		return 0;
139 	if (cfg->vector != IRQ_VECTOR_UNASSIGNED)
140 		return -EBUSY;
141 	for_each_cpu(cpu, &mask)
142 		per_cpu(vector_irq, cpu)[vector] = irq;
143 	cfg->vector = vector;
144 	cfg->domain = domain;
145 	irq_status[irq] = IRQ_USED;
146 	cpumask_or(&vector_table[vector], &vector_table[vector], &domain);
147 	return 0;
148 }
149 
150 int bind_irq_vector(int irq, int vector, cpumask_t domain)
151 {
152 	unsigned long flags;
153 	int ret;
154 
155 	spin_lock_irqsave(&vector_lock, flags);
156 	ret = __bind_irq_vector(irq, vector, domain);
157 	spin_unlock_irqrestore(&vector_lock, flags);
158 	return ret;
159 }
160 
161 static void __clear_irq_vector(int irq)
162 {
163 	int vector, cpu;
164 	cpumask_t domain;
165 	struct irq_cfg *cfg = &irq_cfg[irq];
166 
167 	BUG_ON((unsigned)irq >= NR_IRQS);
168 	BUG_ON(cfg->vector == IRQ_VECTOR_UNASSIGNED);
169 	vector = cfg->vector;
170 	domain = cfg->domain;
171 	for_each_cpu_and(cpu, &cfg->domain, cpu_online_mask)
172 		per_cpu(vector_irq, cpu)[vector] = -1;
173 	cfg->vector = IRQ_VECTOR_UNASSIGNED;
174 	cfg->domain = CPU_MASK_NONE;
175 	irq_status[irq] = IRQ_UNUSED;
176 	cpumask_andnot(&vector_table[vector], &vector_table[vector], &domain);
177 }
178 
179 static void clear_irq_vector(int irq)
180 {
181 	unsigned long flags;
182 
183 	spin_lock_irqsave(&vector_lock, flags);
184 	__clear_irq_vector(irq);
185 	spin_unlock_irqrestore(&vector_lock, flags);
186 }
187 
188 int
189 ia64_native_assign_irq_vector (int irq)
190 {
191 	unsigned long flags;
192 	int vector, cpu;
193 	cpumask_t domain = CPU_MASK_NONE;
194 
195 	vector = -ENOSPC;
196 
197 	spin_lock_irqsave(&vector_lock, flags);
198 	for_each_online_cpu(cpu) {
199 		domain = vector_allocation_domain(cpu);
200 		vector = find_unassigned_vector(domain);
201 		if (vector >= 0)
202 			break;
203 	}
204 	if (vector < 0)
205 		goto out;
206 	if (irq == AUTO_ASSIGN)
207 		irq = vector;
208 	BUG_ON(__bind_irq_vector(irq, vector, domain));
209  out:
210 	spin_unlock_irqrestore(&vector_lock, flags);
211 	return vector;
212 }
213 
214 void
215 ia64_native_free_irq_vector (int vector)
216 {
217 	if (vector < IA64_FIRST_DEVICE_VECTOR ||
218 	    vector > IA64_LAST_DEVICE_VECTOR)
219 		return;
220 	clear_irq_vector(vector);
221 }
222 
223 int
224 reserve_irq_vector (int vector)
225 {
226 	if (vector < IA64_FIRST_DEVICE_VECTOR ||
227 	    vector > IA64_LAST_DEVICE_VECTOR)
228 		return -EINVAL;
229 	return !!bind_irq_vector(vector, vector, CPU_MASK_ALL);
230 }
231 
232 /*
233  * Initialize vector_irq on a new cpu. This function must be called
234  * with vector_lock held.
235  */
236 void __setup_vector_irq(int cpu)
237 {
238 	int irq, vector;
239 
240 	/* Clear vector_irq */
241 	for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
242 		per_cpu(vector_irq, cpu)[vector] = -1;
243 	/* Mark the inuse vectors */
244 	for (irq = 0; irq < NR_IRQS; ++irq) {
245 		if (!cpumask_test_cpu(cpu, &irq_cfg[irq].domain))
246 			continue;
247 		vector = irq_to_vector(irq);
248 		per_cpu(vector_irq, cpu)[vector] = irq;
249 	}
250 }
251 
252 #if defined(CONFIG_SMP) && (defined(CONFIG_IA64_GENERIC) || defined(CONFIG_IA64_DIG))
253 
254 static enum vector_domain_type {
255 	VECTOR_DOMAIN_NONE,
256 	VECTOR_DOMAIN_PERCPU
257 } vector_domain_type = VECTOR_DOMAIN_NONE;
258 
259 static cpumask_t vector_allocation_domain(int cpu)
260 {
261 	if (vector_domain_type == VECTOR_DOMAIN_PERCPU)
262 		return *cpumask_of(cpu);
263 	return CPU_MASK_ALL;
264 }
265 
266 static int __irq_prepare_move(int irq, int cpu)
267 {
268 	struct irq_cfg *cfg = &irq_cfg[irq];
269 	int vector;
270 	cpumask_t domain;
271 
272 	if (cfg->move_in_progress || cfg->move_cleanup_count)
273 		return -EBUSY;
274 	if (cfg->vector == IRQ_VECTOR_UNASSIGNED || !cpu_online(cpu))
275 		return -EINVAL;
276 	if (cpumask_test_cpu(cpu, &cfg->domain))
277 		return 0;
278 	domain = vector_allocation_domain(cpu);
279 	vector = find_unassigned_vector(domain);
280 	if (vector < 0)
281 		return -ENOSPC;
282 	cfg->move_in_progress = 1;
283 	cfg->old_domain = cfg->domain;
284 	cfg->vector = IRQ_VECTOR_UNASSIGNED;
285 	cfg->domain = CPU_MASK_NONE;
286 	BUG_ON(__bind_irq_vector(irq, vector, domain));
287 	return 0;
288 }
289 
290 int irq_prepare_move(int irq, int cpu)
291 {
292 	unsigned long flags;
293 	int ret;
294 
295 	spin_lock_irqsave(&vector_lock, flags);
296 	ret = __irq_prepare_move(irq, cpu);
297 	spin_unlock_irqrestore(&vector_lock, flags);
298 	return ret;
299 }
300 
301 void irq_complete_move(unsigned irq)
302 {
303 	struct irq_cfg *cfg = &irq_cfg[irq];
304 	cpumask_t cleanup_mask;
305 	int i;
306 
307 	if (likely(!cfg->move_in_progress))
308 		return;
309 
310 	if (unlikely(cpumask_test_cpu(smp_processor_id(), &cfg->old_domain)))
311 		return;
312 
313 	cpumask_and(&cleanup_mask, &cfg->old_domain, cpu_online_mask);
314 	cfg->move_cleanup_count = cpumask_weight(&cleanup_mask);
315 	for_each_cpu(i, &cleanup_mask)
316 		platform_send_ipi(i, IA64_IRQ_MOVE_VECTOR, IA64_IPI_DM_INT, 0);
317 	cfg->move_in_progress = 0;
318 }
319 
320 static irqreturn_t smp_irq_move_cleanup_interrupt(int irq, void *dev_id)
321 {
322 	int me = smp_processor_id();
323 	ia64_vector vector;
324 	unsigned long flags;
325 
326 	for (vector = IA64_FIRST_DEVICE_VECTOR;
327 	     vector < IA64_LAST_DEVICE_VECTOR; vector++) {
328 		int irq;
329 		struct irq_desc *desc;
330 		struct irq_cfg *cfg;
331 		irq = __this_cpu_read(vector_irq[vector]);
332 		if (irq < 0)
333 			continue;
334 
335 		desc = irq_to_desc(irq);
336 		cfg = irq_cfg + irq;
337 		raw_spin_lock(&desc->lock);
338 		if (!cfg->move_cleanup_count)
339 			goto unlock;
340 
341 		if (!cpumask_test_cpu(me, &cfg->old_domain))
342 			goto unlock;
343 
344 		spin_lock_irqsave(&vector_lock, flags);
345 		__this_cpu_write(vector_irq[vector], -1);
346 		cpumask_clear_cpu(me, &vector_table[vector]);
347 		spin_unlock_irqrestore(&vector_lock, flags);
348 		cfg->move_cleanup_count--;
349 	unlock:
350 		raw_spin_unlock(&desc->lock);
351 	}
352 	return IRQ_HANDLED;
353 }
354 
355 static struct irqaction irq_move_irqaction = {
356 	.handler =	smp_irq_move_cleanup_interrupt,
357 	.name =		"irq_move"
358 };
359 
360 static int __init parse_vector_domain(char *arg)
361 {
362 	if (!arg)
363 		return -EINVAL;
364 	if (!strcmp(arg, "percpu")) {
365 		vector_domain_type = VECTOR_DOMAIN_PERCPU;
366 		no_int_routing = 1;
367 	}
368 	return 0;
369 }
370 early_param("vector", parse_vector_domain);
371 #else
372 static cpumask_t vector_allocation_domain(int cpu)
373 {
374 	return CPU_MASK_ALL;
375 }
376 #endif
377 
378 
379 void destroy_and_reserve_irq(unsigned int irq)
380 {
381 	unsigned long flags;
382 
383 	irq_init_desc(irq);
384 	spin_lock_irqsave(&vector_lock, flags);
385 	__clear_irq_vector(irq);
386 	irq_status[irq] = IRQ_RSVD;
387 	spin_unlock_irqrestore(&vector_lock, flags);
388 }
389 
390 /*
391  * Dynamic irq allocate and deallocation for MSI
392  */
393 int create_irq(void)
394 {
395 	unsigned long flags;
396 	int irq, vector, cpu;
397 	cpumask_t domain = CPU_MASK_NONE;
398 
399 	irq = vector = -ENOSPC;
400 	spin_lock_irqsave(&vector_lock, flags);
401 	for_each_online_cpu(cpu) {
402 		domain = vector_allocation_domain(cpu);
403 		vector = find_unassigned_vector(domain);
404 		if (vector >= 0)
405 			break;
406 	}
407 	if (vector < 0)
408 		goto out;
409 	irq = find_unassigned_irq();
410 	if (irq < 0)
411 		goto out;
412 	BUG_ON(__bind_irq_vector(irq, vector, domain));
413  out:
414 	spin_unlock_irqrestore(&vector_lock, flags);
415 	if (irq >= 0)
416 		irq_init_desc(irq);
417 	return irq;
418 }
419 
420 void destroy_irq(unsigned int irq)
421 {
422 	irq_init_desc(irq);
423 	clear_irq_vector(irq);
424 }
425 
426 #ifdef CONFIG_SMP
427 #	define IS_RESCHEDULE(vec)	(vec == IA64_IPI_RESCHEDULE)
428 #	define IS_LOCAL_TLB_FLUSH(vec)	(vec == IA64_IPI_LOCAL_TLB_FLUSH)
429 #else
430 #	define IS_RESCHEDULE(vec)	(0)
431 #	define IS_LOCAL_TLB_FLUSH(vec)	(0)
432 #endif
433 /*
434  * That's where the IVT branches when we get an external
435  * interrupt. This branches to the correct hardware IRQ handler via
436  * function ptr.
437  */
438 void
439 ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
440 {
441 	struct pt_regs *old_regs = set_irq_regs(regs);
442 	unsigned long saved_tpr;
443 
444 #if IRQ_DEBUG
445 	{
446 		unsigned long bsp, sp;
447 
448 		/*
449 		 * Note: if the interrupt happened while executing in
450 		 * the context switch routine (ia64_switch_to), we may
451 		 * get a spurious stack overflow here.  This is
452 		 * because the register and the memory stack are not
453 		 * switched atomically.
454 		 */
455 		bsp = ia64_getreg(_IA64_REG_AR_BSP);
456 		sp = ia64_getreg(_IA64_REG_SP);
457 
458 		if ((sp - bsp) < 1024) {
459 			static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
460 
461 			if (__ratelimit(&ratelimit)) {
462 				printk("ia64_handle_irq: DANGER: less than "
463 				       "1KB of free stack space!!\n"
464 				       "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
465 			}
466 		}
467 	}
468 #endif /* IRQ_DEBUG */
469 
470 	/*
471 	 * Always set TPR to limit maximum interrupt nesting depth to
472 	 * 16 (without this, it would be ~240, which could easily lead
473 	 * to kernel stack overflows).
474 	 */
475 	irq_enter();
476 	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
477 	ia64_srlz_d();
478 	while (vector != IA64_SPURIOUS_INT_VECTOR) {
479 		int irq = local_vector_to_irq(vector);
480 
481 		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
482 			smp_local_flush_tlb();
483 			kstat_incr_irq_this_cpu(irq);
484 		} else if (unlikely(IS_RESCHEDULE(vector))) {
485 			scheduler_ipi();
486 			kstat_incr_irq_this_cpu(irq);
487 		} else {
488 			ia64_setreg(_IA64_REG_CR_TPR, vector);
489 			ia64_srlz_d();
490 
491 			if (unlikely(irq < 0)) {
492 				printk(KERN_ERR "%s: Unexpected interrupt "
493 				       "vector %d on CPU %d is not mapped "
494 				       "to any IRQ!\n", __func__, vector,
495 				       smp_processor_id());
496 			} else
497 				generic_handle_irq(irq);
498 
499 			/*
500 			 * Disable interrupts and send EOI:
501 			 */
502 			local_irq_disable();
503 			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
504 		}
505 		ia64_eoi();
506 		vector = ia64_get_ivr();
507 	}
508 	/*
509 	 * This must be done *after* the ia64_eoi().  For example, the keyboard softirq
510 	 * handler needs to be able to wait for further keyboard interrupts, which can't
511 	 * come through until ia64_eoi() has been done.
512 	 */
513 	irq_exit();
514 	set_irq_regs(old_regs);
515 }
516 
517 #ifdef CONFIG_HOTPLUG_CPU
518 /*
519  * This function emulates a interrupt processing when a cpu is about to be
520  * brought down.
521  */
522 void ia64_process_pending_intr(void)
523 {
524 	ia64_vector vector;
525 	unsigned long saved_tpr;
526 	extern unsigned int vectors_in_migration[NR_IRQS];
527 
528 	vector = ia64_get_ivr();
529 
530 	irq_enter();
531 	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
532 	ia64_srlz_d();
533 
534 	 /*
535 	  * Perform normal interrupt style processing
536 	  */
537 	while (vector != IA64_SPURIOUS_INT_VECTOR) {
538 		int irq = local_vector_to_irq(vector);
539 
540 		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
541 			smp_local_flush_tlb();
542 			kstat_incr_irq_this_cpu(irq);
543 		} else if (unlikely(IS_RESCHEDULE(vector))) {
544 			kstat_incr_irq_this_cpu(irq);
545 		} else {
546 			struct pt_regs *old_regs = set_irq_regs(NULL);
547 
548 			ia64_setreg(_IA64_REG_CR_TPR, vector);
549 			ia64_srlz_d();
550 
551 			/*
552 			 * Now try calling normal ia64_handle_irq as it would have got called
553 			 * from a real intr handler. Try passing null for pt_regs, hopefully
554 			 * it will work. I hope it works!.
555 			 * Probably could shared code.
556 			 */
557 			if (unlikely(irq < 0)) {
558 				printk(KERN_ERR "%s: Unexpected interrupt "
559 				       "vector %d on CPU %d not being mapped "
560 				       "to any IRQ!!\n", __func__, vector,
561 				       smp_processor_id());
562 			} else {
563 				vectors_in_migration[irq]=0;
564 				generic_handle_irq(irq);
565 			}
566 			set_irq_regs(old_regs);
567 
568 			/*
569 			 * Disable interrupts and send EOI
570 			 */
571 			local_irq_disable();
572 			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
573 		}
574 		ia64_eoi();
575 		vector = ia64_get_ivr();
576 	}
577 	irq_exit();
578 }
579 #endif
580 
581 
582 #ifdef CONFIG_SMP
583 
584 static irqreturn_t dummy_handler (int irq, void *dev_id)
585 {
586 	BUG();
587 }
588 
589 static struct irqaction ipi_irqaction = {
590 	.handler =	handle_IPI,
591 	.name =		"IPI"
592 };
593 
594 /*
595  * KVM uses this interrupt to force a cpu out of guest mode
596  */
597 static struct irqaction resched_irqaction = {
598 	.handler =	dummy_handler,
599 	.name =		"resched"
600 };
601 
602 static struct irqaction tlb_irqaction = {
603 	.handler =	dummy_handler,
604 	.name =		"tlb_flush"
605 };
606 
607 #endif
608 
609 void
610 ia64_native_register_percpu_irq (ia64_vector vec, struct irqaction *action)
611 {
612 	unsigned int irq;
613 
614 	irq = vec;
615 	BUG_ON(bind_irq_vector(irq, vec, CPU_MASK_ALL));
616 	irq_set_status_flags(irq, IRQ_PER_CPU);
617 	irq_set_chip(irq, &irq_type_ia64_lsapic);
618 	if (action)
619 		setup_irq(irq, action);
620 	irq_set_handler(irq, handle_percpu_irq);
621 }
622 
623 void __init
624 ia64_native_register_ipi(void)
625 {
626 #ifdef CONFIG_SMP
627 	register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
628 	register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
629 	register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &tlb_irqaction);
630 #endif
631 }
632 
633 void __init
634 init_IRQ (void)
635 {
636 #ifdef CONFIG_ACPI
637 	acpi_boot_init();
638 #endif
639 	ia64_register_ipi();
640 	register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
641 #ifdef CONFIG_SMP
642 #if defined(CONFIG_IA64_GENERIC) || defined(CONFIG_IA64_DIG)
643 	if (vector_domain_type != VECTOR_DOMAIN_NONE)
644 		register_percpu_irq(IA64_IRQ_MOVE_VECTOR, &irq_move_irqaction);
645 #endif
646 #endif
647 #ifdef CONFIG_PERFMON
648 	pfm_init_percpu();
649 #endif
650 	platform_irq_init();
651 }
652 
653 void
654 ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
655 {
656 	void __iomem *ipi_addr;
657 	unsigned long ipi_data;
658 	unsigned long phys_cpu_id;
659 
660 	phys_cpu_id = cpu_physical_id(cpu);
661 
662 	/*
663 	 * cpu number is in 8bit ID and 8bit EID
664 	 */
665 
666 	ipi_data = (delivery_mode << 8) | (vector & 0xff);
667 	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
668 
669 	writeq(ipi_data, ipi_addr);
670 }
671