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v3.1
 
  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/random.h>	/* for rand_initialize_irq() */
 27#include <linux/signal.h>
 28#include <linux/smp.h>
 29#include <linux/threads.h>
 30#include <linux/bitops.h>
 31#include <linux/irq.h>
 32#include <linux/ratelimit.h>
 33#include <linux/acpi.h>
 34#include <linux/sched.h>
 35
 36#include <asm/delay.h>
 37#include <asm/intrinsics.h>
 38#include <asm/io.h>
 39#include <asm/hw_irq.h>
 40#include <asm/machvec.h>
 41#include <asm/pgtable.h>
 42#include <asm/system.h>
 43#include <asm/tlbflush.h>
 44
 45#ifdef CONFIG_PERFMON
 46# include <asm/perfmon.h>
 47#endif
 48
 49#define IRQ_DEBUG	0
 50
 51#define IRQ_VECTOR_UNASSIGNED	(0)
 52
 53#define IRQ_UNUSED		(0)
 54#define IRQ_USED		(1)
 55#define IRQ_RSVD		(2)
 56
 57/* These can be overridden in platform_irq_init */
 58int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
 59int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;
 60
 61/* default base addr of IPI table */
 62void __iomem *ipi_base_addr = ((void __iomem *)
 63			       (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));
 64
 65static cpumask_t vector_allocation_domain(int cpu);
 66
 67/*
 68 * Legacy IRQ to IA-64 vector translation table.
 69 */
 70__u8 isa_irq_to_vector_map[16] = {
 71	/* 8259 IRQ translation, first 16 entries */
 72	0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
 73	0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
 74};
 75EXPORT_SYMBOL(isa_irq_to_vector_map);
 76
 77DEFINE_SPINLOCK(vector_lock);
 78
 79struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
 80	[0 ... NR_IRQS - 1] = {
 81		.vector = IRQ_VECTOR_UNASSIGNED,
 82		.domain = CPU_MASK_NONE
 83	}
 84};
 85
 86DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = {
 87	[0 ... IA64_NUM_VECTORS - 1] = -1
 88};
 89
 90static cpumask_t vector_table[IA64_NUM_VECTORS] = {
 91	[0 ... IA64_NUM_VECTORS - 1] = CPU_MASK_NONE
 92};
 93
 94static int irq_status[NR_IRQS] = {
 95	[0 ... NR_IRQS -1] = IRQ_UNUSED
 96};
 97
 98int check_irq_used(int irq)
 99{
100	if (irq_status[irq] == IRQ_USED)
101		return 1;
102
103	return -1;
104}
105
106static inline int find_unassigned_irq(void)
107{
108	int irq;
109
110	for (irq = IA64_FIRST_DEVICE_VECTOR; irq < NR_IRQS; irq++)
111		if (irq_status[irq] == IRQ_UNUSED)
112			return irq;
113	return -ENOSPC;
114}
115
116static inline int find_unassigned_vector(cpumask_t domain)
117{
118	cpumask_t mask;
119	int pos, vector;
120
121	cpus_and(mask, domain, cpu_online_map);
122	if (cpus_empty(mask))
123		return -EINVAL;
124
125	for (pos = 0; pos < IA64_NUM_DEVICE_VECTORS; pos++) {
126		vector = IA64_FIRST_DEVICE_VECTOR + pos;
127		cpus_and(mask, domain, vector_table[vector]);
128		if (!cpus_empty(mask))
129			continue;
130		return vector;
131	}
132	return -ENOSPC;
133}
134
135static int __bind_irq_vector(int irq, int vector, cpumask_t domain)
136{
137	cpumask_t mask;
138	int cpu;
139	struct irq_cfg *cfg = &irq_cfg[irq];
140
141	BUG_ON((unsigned)irq >= NR_IRQS);
142	BUG_ON((unsigned)vector >= IA64_NUM_VECTORS);
143
144	cpus_and(mask, domain, cpu_online_map);
145	if (cpus_empty(mask))
146		return -EINVAL;
147	if ((cfg->vector == vector) && cpus_equal(cfg->domain, domain))
148		return 0;
149	if (cfg->vector != IRQ_VECTOR_UNASSIGNED)
150		return -EBUSY;
151	for_each_cpu_mask(cpu, mask)
152		per_cpu(vector_irq, cpu)[vector] = irq;
153	cfg->vector = vector;
154	cfg->domain = domain;
155	irq_status[irq] = IRQ_USED;
156	cpus_or(vector_table[vector], vector_table[vector], domain);
157	return 0;
158}
159
160int bind_irq_vector(int irq, int vector, cpumask_t domain)
161{
162	unsigned long flags;
163	int ret;
164
165	spin_lock_irqsave(&vector_lock, flags);
166	ret = __bind_irq_vector(irq, vector, domain);
167	spin_unlock_irqrestore(&vector_lock, flags);
168	return ret;
169}
170
171static void __clear_irq_vector(int irq)
172{
173	int vector, cpu;
174	cpumask_t mask;
175	cpumask_t domain;
176	struct irq_cfg *cfg = &irq_cfg[irq];
177
178	BUG_ON((unsigned)irq >= NR_IRQS);
179	BUG_ON(cfg->vector == IRQ_VECTOR_UNASSIGNED);
180	vector = cfg->vector;
181	domain = cfg->domain;
182	cpus_and(mask, cfg->domain, cpu_online_map);
183	for_each_cpu_mask(cpu, mask)
184		per_cpu(vector_irq, cpu)[vector] = -1;
185	cfg->vector = IRQ_VECTOR_UNASSIGNED;
186	cfg->domain = CPU_MASK_NONE;
187	irq_status[irq] = IRQ_UNUSED;
188	cpus_andnot(vector_table[vector], vector_table[vector], domain);
189}
190
191static void clear_irq_vector(int irq)
192{
193	unsigned long flags;
194
195	spin_lock_irqsave(&vector_lock, flags);
196	__clear_irq_vector(irq);
197	spin_unlock_irqrestore(&vector_lock, flags);
198}
199
200int
201ia64_native_assign_irq_vector (int irq)
202{
203	unsigned long flags;
204	int vector, cpu;
205	cpumask_t domain = CPU_MASK_NONE;
206
207	vector = -ENOSPC;
208
209	spin_lock_irqsave(&vector_lock, flags);
210	for_each_online_cpu(cpu) {
211		domain = vector_allocation_domain(cpu);
212		vector = find_unassigned_vector(domain);
213		if (vector >= 0)
214			break;
215	}
216	if (vector < 0)
217		goto out;
218	if (irq == AUTO_ASSIGN)
219		irq = vector;
220	BUG_ON(__bind_irq_vector(irq, vector, domain));
221 out:
222	spin_unlock_irqrestore(&vector_lock, flags);
223	return vector;
224}
225
226void
227ia64_native_free_irq_vector (int vector)
228{
229	if (vector < IA64_FIRST_DEVICE_VECTOR ||
230	    vector > IA64_LAST_DEVICE_VECTOR)
231		return;
232	clear_irq_vector(vector);
233}
234
235int
236reserve_irq_vector (int vector)
237{
238	if (vector < IA64_FIRST_DEVICE_VECTOR ||
239	    vector > IA64_LAST_DEVICE_VECTOR)
240		return -EINVAL;
241	return !!bind_irq_vector(vector, vector, CPU_MASK_ALL);
242}
243
244/*
245 * Initialize vector_irq on a new cpu. This function must be called
246 * with vector_lock held.
247 */
248void __setup_vector_irq(int cpu)
249{
250	int irq, vector;
251
252	/* Clear vector_irq */
253	for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
254		per_cpu(vector_irq, cpu)[vector] = -1;
255	/* Mark the inuse vectors */
256	for (irq = 0; irq < NR_IRQS; ++irq) {
257		if (!cpu_isset(cpu, irq_cfg[irq].domain))
258			continue;
259		vector = irq_to_vector(irq);
260		per_cpu(vector_irq, cpu)[vector] = irq;
261	}
262}
263
264#if defined(CONFIG_SMP) && (defined(CONFIG_IA64_GENERIC) || defined(CONFIG_IA64_DIG))
265
266static enum vector_domain_type {
267	VECTOR_DOMAIN_NONE,
268	VECTOR_DOMAIN_PERCPU
269} vector_domain_type = VECTOR_DOMAIN_NONE;
270
271static cpumask_t vector_allocation_domain(int cpu)
272{
273	if (vector_domain_type == VECTOR_DOMAIN_PERCPU)
274		return cpumask_of_cpu(cpu);
275	return CPU_MASK_ALL;
276}
277
278static int __irq_prepare_move(int irq, int cpu)
279{
280	struct irq_cfg *cfg = &irq_cfg[irq];
281	int vector;
282	cpumask_t domain;
283
284	if (cfg->move_in_progress || cfg->move_cleanup_count)
285		return -EBUSY;
286	if (cfg->vector == IRQ_VECTOR_UNASSIGNED || !cpu_online(cpu))
287		return -EINVAL;
288	if (cpu_isset(cpu, cfg->domain))
289		return 0;
290	domain = vector_allocation_domain(cpu);
291	vector = find_unassigned_vector(domain);
292	if (vector < 0)
293		return -ENOSPC;
294	cfg->move_in_progress = 1;
295	cfg->old_domain = cfg->domain;
296	cfg->vector = IRQ_VECTOR_UNASSIGNED;
297	cfg->domain = CPU_MASK_NONE;
298	BUG_ON(__bind_irq_vector(irq, vector, domain));
299	return 0;
300}
301
302int irq_prepare_move(int irq, int cpu)
303{
304	unsigned long flags;
305	int ret;
306
307	spin_lock_irqsave(&vector_lock, flags);
308	ret = __irq_prepare_move(irq, cpu);
309	spin_unlock_irqrestore(&vector_lock, flags);
310	return ret;
311}
312
313void irq_complete_move(unsigned irq)
314{
315	struct irq_cfg *cfg = &irq_cfg[irq];
316	cpumask_t cleanup_mask;
317	int i;
318
319	if (likely(!cfg->move_in_progress))
320		return;
321
322	if (unlikely(cpu_isset(smp_processor_id(), cfg->old_domain)))
323		return;
324
325	cpus_and(cleanup_mask, cfg->old_domain, cpu_online_map);
326	cfg->move_cleanup_count = cpus_weight(cleanup_mask);
327	for_each_cpu_mask(i, cleanup_mask)
328		platform_send_ipi(i, IA64_IRQ_MOVE_VECTOR, IA64_IPI_DM_INT, 0);
329	cfg->move_in_progress = 0;
330}
331
332static irqreturn_t smp_irq_move_cleanup_interrupt(int irq, void *dev_id)
333{
334	int me = smp_processor_id();
335	ia64_vector vector;
336	unsigned long flags;
337
338	for (vector = IA64_FIRST_DEVICE_VECTOR;
339	     vector < IA64_LAST_DEVICE_VECTOR; vector++) {
340		int irq;
341		struct irq_desc *desc;
342		struct irq_cfg *cfg;
343		irq = __get_cpu_var(vector_irq)[vector];
344		if (irq < 0)
345			continue;
346
347		desc = irq_to_desc(irq);
348		cfg = irq_cfg + irq;
349		raw_spin_lock(&desc->lock);
350		if (!cfg->move_cleanup_count)
351			goto unlock;
352
353		if (!cpu_isset(me, cfg->old_domain))
354			goto unlock;
355
356		spin_lock_irqsave(&vector_lock, flags);
357		__get_cpu_var(vector_irq)[vector] = -1;
358		cpu_clear(me, vector_table[vector]);
359		spin_unlock_irqrestore(&vector_lock, flags);
360		cfg->move_cleanup_count--;
361	unlock:
362		raw_spin_unlock(&desc->lock);
363	}
364	return IRQ_HANDLED;
365}
366
367static struct irqaction irq_move_irqaction = {
368	.handler =	smp_irq_move_cleanup_interrupt,
369	.flags =	IRQF_DISABLED,
370	.name =		"irq_move"
371};
372
373static int __init parse_vector_domain(char *arg)
374{
375	if (!arg)
376		return -EINVAL;
377	if (!strcmp(arg, "percpu")) {
378		vector_domain_type = VECTOR_DOMAIN_PERCPU;
379		no_int_routing = 1;
380	}
381	return 0;
382}
383early_param("vector", parse_vector_domain);
384#else
385static cpumask_t vector_allocation_domain(int cpu)
386{
387	return CPU_MASK_ALL;
388}
389#endif
390
391
392void destroy_and_reserve_irq(unsigned int irq)
393{
394	unsigned long flags;
395
396	dynamic_irq_cleanup(irq);
397
398	spin_lock_irqsave(&vector_lock, flags);
399	__clear_irq_vector(irq);
400	irq_status[irq] = IRQ_RSVD;
401	spin_unlock_irqrestore(&vector_lock, flags);
402}
403
404/*
405 * Dynamic irq allocate and deallocation for MSI
406 */
407int create_irq(void)
408{
409	unsigned long flags;
410	int irq, vector, cpu;
411	cpumask_t domain = CPU_MASK_NONE;
412
413	irq = vector = -ENOSPC;
414	spin_lock_irqsave(&vector_lock, flags);
415	for_each_online_cpu(cpu) {
416		domain = vector_allocation_domain(cpu);
417		vector = find_unassigned_vector(domain);
418		if (vector >= 0)
419			break;
420	}
421	if (vector < 0)
422		goto out;
423	irq = find_unassigned_irq();
424	if (irq < 0)
425		goto out;
426	BUG_ON(__bind_irq_vector(irq, vector, domain));
427 out:
428	spin_unlock_irqrestore(&vector_lock, flags);
429	if (irq >= 0)
430		dynamic_irq_init(irq);
431	return irq;
432}
433
434void destroy_irq(unsigned int irq)
435{
436	dynamic_irq_cleanup(irq);
437	clear_irq_vector(irq);
438}
439
440#ifdef CONFIG_SMP
441#	define IS_RESCHEDULE(vec)	(vec == IA64_IPI_RESCHEDULE)
442#	define IS_LOCAL_TLB_FLUSH(vec)	(vec == IA64_IPI_LOCAL_TLB_FLUSH)
443#else
444#	define IS_RESCHEDULE(vec)	(0)
445#	define IS_LOCAL_TLB_FLUSH(vec)	(0)
446#endif
447/*
448 * That's where the IVT branches when we get an external
449 * interrupt. This branches to the correct hardware IRQ handler via
450 * function ptr.
451 */
452void
453ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
454{
455	struct pt_regs *old_regs = set_irq_regs(regs);
456	unsigned long saved_tpr;
457
458#if IRQ_DEBUG
459	{
460		unsigned long bsp, sp;
461
462		/*
463		 * Note: if the interrupt happened while executing in
464		 * the context switch routine (ia64_switch_to), we may
465		 * get a spurious stack overflow here.  This is
466		 * because the register and the memory stack are not
467		 * switched atomically.
468		 */
469		bsp = ia64_getreg(_IA64_REG_AR_BSP);
470		sp = ia64_getreg(_IA64_REG_SP);
471
472		if ((sp - bsp) < 1024) {
473			static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
474
475			if (__ratelimit(&ratelimit)) {
476				printk("ia64_handle_irq: DANGER: less than "
477				       "1KB of free stack space!!\n"
478				       "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
479			}
480		}
481	}
482#endif /* IRQ_DEBUG */
483
484	/*
485	 * Always set TPR to limit maximum interrupt nesting depth to
486	 * 16 (without this, it would be ~240, which could easily lead
487	 * to kernel stack overflows).
488	 */
489	irq_enter();
490	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
491	ia64_srlz_d();
492	while (vector != IA64_SPURIOUS_INT_VECTOR) {
493		int irq = local_vector_to_irq(vector);
494		struct irq_desc *desc = irq_to_desc(irq);
495
496		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
497			smp_local_flush_tlb();
498			kstat_incr_irqs_this_cpu(irq, desc);
499		} else if (unlikely(IS_RESCHEDULE(vector))) {
500			scheduler_ipi();
501			kstat_incr_irqs_this_cpu(irq, desc);
502		} else {
503			ia64_setreg(_IA64_REG_CR_TPR, vector);
504			ia64_srlz_d();
505
506			if (unlikely(irq < 0)) {
507				printk(KERN_ERR "%s: Unexpected interrupt "
508				       "vector %d on CPU %d is not mapped "
509				       "to any IRQ!\n", __func__, vector,
510				       smp_processor_id());
511			} else
512				generic_handle_irq(irq);
513
514			/*
515			 * Disable interrupts and send EOI:
516			 */
517			local_irq_disable();
518			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
519		}
520		ia64_eoi();
521		vector = ia64_get_ivr();
522	}
523	/*
524	 * This must be done *after* the ia64_eoi().  For example, the keyboard softirq
525	 * handler needs to be able to wait for further keyboard interrupts, which can't
526	 * come through until ia64_eoi() has been done.
527	 */
528	irq_exit();
529	set_irq_regs(old_regs);
530}
531
532#ifdef CONFIG_HOTPLUG_CPU
533/*
534 * This function emulates a interrupt processing when a cpu is about to be
535 * brought down.
536 */
537void ia64_process_pending_intr(void)
538{
539	ia64_vector vector;
540	unsigned long saved_tpr;
541	extern unsigned int vectors_in_migration[NR_IRQS];
542
543	vector = ia64_get_ivr();
544
545	irq_enter();
546	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
547	ia64_srlz_d();
548
549	 /*
550	  * Perform normal interrupt style processing
551	  */
552	while (vector != IA64_SPURIOUS_INT_VECTOR) {
553		int irq = local_vector_to_irq(vector);
554		struct irq_desc *desc = irq_to_desc(irq);
555
556		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
557			smp_local_flush_tlb();
558			kstat_incr_irqs_this_cpu(irq, desc);
559		} else if (unlikely(IS_RESCHEDULE(vector))) {
560			kstat_incr_irqs_this_cpu(irq, desc);
561		} else {
562			struct pt_regs *old_regs = set_irq_regs(NULL);
563
564			ia64_setreg(_IA64_REG_CR_TPR, vector);
565			ia64_srlz_d();
566
567			/*
568			 * Now try calling normal ia64_handle_irq as it would have got called
569			 * from a real intr handler. Try passing null for pt_regs, hopefully
570			 * it will work. I hope it works!.
571			 * Probably could shared code.
572			 */
573			if (unlikely(irq < 0)) {
574				printk(KERN_ERR "%s: Unexpected interrupt "
575				       "vector %d on CPU %d not being mapped "
576				       "to any IRQ!!\n", __func__, vector,
577				       smp_processor_id());
578			} else {
579				vectors_in_migration[irq]=0;
580				generic_handle_irq(irq);
581			}
582			set_irq_regs(old_regs);
583
584			/*
585			 * Disable interrupts and send EOI
586			 */
587			local_irq_disable();
588			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
589		}
590		ia64_eoi();
591		vector = ia64_get_ivr();
592	}
593	irq_exit();
594}
595#endif
596
597
598#ifdef CONFIG_SMP
599
600static irqreturn_t dummy_handler (int irq, void *dev_id)
601{
602	BUG();
 
603}
604
605static struct irqaction ipi_irqaction = {
606	.handler =	handle_IPI,
607	.flags =	IRQF_DISABLED,
608	.name =		"IPI"
609};
610
611/*
612 * KVM uses this interrupt to force a cpu out of guest mode
613 */
614static struct irqaction resched_irqaction = {
615	.handler =	dummy_handler,
616	.flags =	IRQF_DISABLED,
617	.name =		"resched"
618};
619
620static struct irqaction tlb_irqaction = {
621	.handler =	dummy_handler,
622	.flags =	IRQF_DISABLED,
623	.name =		"tlb_flush"
624};
625
626#endif
627
628void
629ia64_native_register_percpu_irq (ia64_vector vec, struct irqaction *action)
 
630{
631	unsigned int irq;
632
633	irq = vec;
634	BUG_ON(bind_irq_vector(irq, vec, CPU_MASK_ALL));
635	irq_set_status_flags(irq, IRQ_PER_CPU);
636	irq_set_chip(irq, &irq_type_ia64_lsapic);
637	if (action)
638		setup_irq(irq, action);
 
639	irq_set_handler(irq, handle_percpu_irq);
640}
641
642void __init
643ia64_native_register_ipi(void)
644{
645#ifdef CONFIG_SMP
646	register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
647	register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
648	register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &tlb_irqaction);
 
649#endif
650}
651
652void __init
653init_IRQ (void)
654{
655#ifdef CONFIG_ACPI
656	acpi_boot_init();
657#endif
658	ia64_register_ipi();
659	register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
660#ifdef CONFIG_SMP
661#if defined(CONFIG_IA64_GENERIC) || defined(CONFIG_IA64_DIG)
662	if (vector_domain_type != VECTOR_DOMAIN_NONE)
663		register_percpu_irq(IA64_IRQ_MOVE_VECTOR, &irq_move_irqaction);
664#endif
 
665#endif
666#ifdef CONFIG_PERFMON
667	pfm_init_percpu();
668#endif
669	platform_irq_init();
670}
671
672void
673ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
674{
675	void __iomem *ipi_addr;
676	unsigned long ipi_data;
677	unsigned long phys_cpu_id;
678
679	phys_cpu_id = cpu_physical_id(cpu);
680
681	/*
682	 * cpu number is in 8bit ID and 8bit EID
683	 */
684
685	ipi_data = (delivery_mode << 8) | (vector & 0xff);
686	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
687
688	writeq(ipi_data, ipi_addr);
689}
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * linux/arch/ia64/kernel/irq_ia64.c
  4 *
  5 * Copyright (C) 1998-2001 Hewlett-Packard Co
  6 *	Stephane Eranian <eranian@hpl.hp.com>
  7 *	David Mosberger-Tang <davidm@hpl.hp.com>
  8 *
  9 *  6/10/99: Updated to bring in sync with x86 version to facilitate
 10 *	     support for SMP and different interrupt controllers.
 11 *
 12 * 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
 13 *                      PCI to vector allocation routine.
 14 * 04/14/2004 Ashok Raj <ashok.raj@intel.com>
 15 *						Added CPU Hotplug handling for IPF.
 16 */
 17
 18#include <linux/module.h>
 19#include <linux/pgtable.h>
 20
 21#include <linux/jiffies.h>
 22#include <linux/errno.h>
 23#include <linux/init.h>
 24#include <linux/interrupt.h>
 25#include <linux/ioport.h>
 26#include <linux/kernel_stat.h>
 27#include <linux/ptrace.h>
 
 28#include <linux/signal.h>
 29#include <linux/smp.h>
 30#include <linux/threads.h>
 31#include <linux/bitops.h>
 32#include <linux/irq.h>
 33#include <linux/ratelimit.h>
 34#include <linux/acpi.h>
 35#include <linux/sched.h>
 36
 37#include <asm/delay.h>
 38#include <asm/intrinsics.h>
 39#include <asm/io.h>
 40#include <asm/hw_irq.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
 
 55int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
 56int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;
 57
 58/* default base addr of IPI table */
 59void __iomem *ipi_base_addr = ((void __iomem *)
 60			       (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));
 61
 62static cpumask_t vector_allocation_domain(int cpu);
 63
 64/*
 65 * Legacy IRQ to IA-64 vector translation table.
 66 */
 67__u8 isa_irq_to_vector_map[16] = {
 68	/* 8259 IRQ translation, first 16 entries */
 69	0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
 70	0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
 71};
 72EXPORT_SYMBOL(isa_irq_to_vector_map);
 73
 74DEFINE_SPINLOCK(vector_lock);
 75
 76struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
 77	[0 ... NR_IRQS - 1] = {
 78		.vector = IRQ_VECTOR_UNASSIGNED,
 79		.domain = CPU_MASK_NONE
 80	}
 81};
 82
 83DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = {
 84	[0 ... IA64_NUM_VECTORS - 1] = -1
 85};
 86
 87static cpumask_t vector_table[IA64_NUM_VECTORS] = {
 88	[0 ... IA64_NUM_VECTORS - 1] = CPU_MASK_NONE
 89};
 90
 91static int irq_status[NR_IRQS] = {
 92	[0 ... NR_IRQS -1] = IRQ_UNUSED
 93};
 94
 
 
 
 
 
 
 
 
 95static inline int find_unassigned_irq(void)
 96{
 97	int irq;
 98
 99	for (irq = IA64_FIRST_DEVICE_VECTOR; irq < NR_IRQS; irq++)
100		if (irq_status[irq] == IRQ_UNUSED)
101			return irq;
102	return -ENOSPC;
103}
104
105static inline int find_unassigned_vector(cpumask_t domain)
106{
107	cpumask_t mask;
108	int pos, vector;
109
110	cpumask_and(&mask, &domain, cpu_online_mask);
111	if (cpumask_empty(&mask))
112		return -EINVAL;
113
114	for (pos = 0; pos < IA64_NUM_DEVICE_VECTORS; pos++) {
115		vector = IA64_FIRST_DEVICE_VECTOR + pos;
116		cpumask_and(&mask, &domain, &vector_table[vector]);
117		if (!cpumask_empty(&mask))
118			continue;
119		return vector;
120	}
121	return -ENOSPC;
122}
123
124static int __bind_irq_vector(int irq, int vector, cpumask_t domain)
125{
126	cpumask_t mask;
127	int cpu;
128	struct irq_cfg *cfg = &irq_cfg[irq];
129
130	BUG_ON((unsigned)irq >= NR_IRQS);
131	BUG_ON((unsigned)vector >= IA64_NUM_VECTORS);
132
133	cpumask_and(&mask, &domain, cpu_online_mask);
134	if (cpumask_empty(&mask))
135		return -EINVAL;
136	if ((cfg->vector == vector) && cpumask_equal(&cfg->domain, &domain))
137		return 0;
138	if (cfg->vector != IRQ_VECTOR_UNASSIGNED)
139		return -EBUSY;
140	for_each_cpu(cpu, &mask)
141		per_cpu(vector_irq, cpu)[vector] = irq;
142	cfg->vector = vector;
143	cfg->domain = domain;
144	irq_status[irq] = IRQ_USED;
145	cpumask_or(&vector_table[vector], &vector_table[vector], &domain);
146	return 0;
147}
148
149int bind_irq_vector(int irq, int vector, cpumask_t domain)
150{
151	unsigned long flags;
152	int ret;
153
154	spin_lock_irqsave(&vector_lock, flags);
155	ret = __bind_irq_vector(irq, vector, domain);
156	spin_unlock_irqrestore(&vector_lock, flags);
157	return ret;
158}
159
160static void __clear_irq_vector(int irq)
161{
162	int vector, cpu;
 
163	cpumask_t domain;
164	struct irq_cfg *cfg = &irq_cfg[irq];
165
166	BUG_ON((unsigned)irq >= NR_IRQS);
167	BUG_ON(cfg->vector == IRQ_VECTOR_UNASSIGNED);
168	vector = cfg->vector;
169	domain = cfg->domain;
170	for_each_cpu_and(cpu, &cfg->domain, cpu_online_mask)
 
171		per_cpu(vector_irq, cpu)[vector] = -1;
172	cfg->vector = IRQ_VECTOR_UNASSIGNED;
173	cfg->domain = CPU_MASK_NONE;
174	irq_status[irq] = IRQ_UNUSED;
175	cpumask_andnot(&vector_table[vector], &vector_table[vector], &domain);
176}
177
178static void clear_irq_vector(int irq)
179{
180	unsigned long flags;
181
182	spin_lock_irqsave(&vector_lock, flags);
183	__clear_irq_vector(irq);
184	spin_unlock_irqrestore(&vector_lock, flags);
185}
186
187int
188ia64_native_assign_irq_vector (int irq)
189{
190	unsigned long flags;
191	int vector, cpu;
192	cpumask_t domain = CPU_MASK_NONE;
193
194	vector = -ENOSPC;
195
196	spin_lock_irqsave(&vector_lock, flags);
197	for_each_online_cpu(cpu) {
198		domain = vector_allocation_domain(cpu);
199		vector = find_unassigned_vector(domain);
200		if (vector >= 0)
201			break;
202	}
203	if (vector < 0)
204		goto out;
205	if (irq == AUTO_ASSIGN)
206		irq = vector;
207	BUG_ON(__bind_irq_vector(irq, vector, domain));
208 out:
209	spin_unlock_irqrestore(&vector_lock, flags);
210	return vector;
211}
212
213void
214ia64_native_free_irq_vector (int vector)
215{
216	if (vector < IA64_FIRST_DEVICE_VECTOR ||
217	    vector > IA64_LAST_DEVICE_VECTOR)
218		return;
219	clear_irq_vector(vector);
220}
221
222int
223reserve_irq_vector (int vector)
224{
225	if (vector < IA64_FIRST_DEVICE_VECTOR ||
226	    vector > IA64_LAST_DEVICE_VECTOR)
227		return -EINVAL;
228	return !!bind_irq_vector(vector, vector, CPU_MASK_ALL);
229}
230
231/*
232 * Initialize vector_irq on a new cpu. This function must be called
233 * with vector_lock held.
234 */
235void __setup_vector_irq(int cpu)
236{
237	int irq, vector;
238
239	/* Clear vector_irq */
240	for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
241		per_cpu(vector_irq, cpu)[vector] = -1;
242	/* Mark the inuse vectors */
243	for (irq = 0; irq < NR_IRQS; ++irq) {
244		if (!cpumask_test_cpu(cpu, &irq_cfg[irq].domain))
245			continue;
246		vector = irq_to_vector(irq);
247		per_cpu(vector_irq, cpu)[vector] = irq;
248	}
249}
250
251#ifdef CONFIG_SMP
252
253static enum vector_domain_type {
254	VECTOR_DOMAIN_NONE,
255	VECTOR_DOMAIN_PERCPU
256} vector_domain_type = VECTOR_DOMAIN_NONE;
257
258static cpumask_t vector_allocation_domain(int cpu)
259{
260	if (vector_domain_type == VECTOR_DOMAIN_PERCPU)
261		return *cpumask_of(cpu);
262	return CPU_MASK_ALL;
263}
264
265static int __irq_prepare_move(int irq, int cpu)
266{
267	struct irq_cfg *cfg = &irq_cfg[irq];
268	int vector;
269	cpumask_t domain;
270
271	if (cfg->move_in_progress || cfg->move_cleanup_count)
272		return -EBUSY;
273	if (cfg->vector == IRQ_VECTOR_UNASSIGNED || !cpu_online(cpu))
274		return -EINVAL;
275	if (cpumask_test_cpu(cpu, &cfg->domain))
276		return 0;
277	domain = vector_allocation_domain(cpu);
278	vector = find_unassigned_vector(domain);
279	if (vector < 0)
280		return -ENOSPC;
281	cfg->move_in_progress = 1;
282	cfg->old_domain = cfg->domain;
283	cfg->vector = IRQ_VECTOR_UNASSIGNED;
284	cfg->domain = CPU_MASK_NONE;
285	BUG_ON(__bind_irq_vector(irq, vector, domain));
286	return 0;
287}
288
289int irq_prepare_move(int irq, int cpu)
290{
291	unsigned long flags;
292	int ret;
293
294	spin_lock_irqsave(&vector_lock, flags);
295	ret = __irq_prepare_move(irq, cpu);
296	spin_unlock_irqrestore(&vector_lock, flags);
297	return ret;
298}
299
300void irq_complete_move(unsigned irq)
301{
302	struct irq_cfg *cfg = &irq_cfg[irq];
303	cpumask_t cleanup_mask;
304	int i;
305
306	if (likely(!cfg->move_in_progress))
307		return;
308
309	if (unlikely(cpumask_test_cpu(smp_processor_id(), &cfg->old_domain)))
310		return;
311
312	cpumask_and(&cleanup_mask, &cfg->old_domain, cpu_online_mask);
313	cfg->move_cleanup_count = cpumask_weight(&cleanup_mask);
314	for_each_cpu(i, &cleanup_mask)
315		ia64_send_ipi(i, IA64_IRQ_MOVE_VECTOR, IA64_IPI_DM_INT, 0);
316	cfg->move_in_progress = 0;
317}
318
319static irqreturn_t smp_irq_move_cleanup_interrupt(int irq, void *dev_id)
320{
321	int me = smp_processor_id();
322	ia64_vector vector;
323	unsigned long flags;
324
325	for (vector = IA64_FIRST_DEVICE_VECTOR;
326	     vector < IA64_LAST_DEVICE_VECTOR; vector++) {
327		int irq;
328		struct irq_desc *desc;
329		struct irq_cfg *cfg;
330		irq = __this_cpu_read(vector_irq[vector]);
331		if (irq < 0)
332			continue;
333
334		desc = irq_to_desc(irq);
335		cfg = irq_cfg + irq;
336		raw_spin_lock(&desc->lock);
337		if (!cfg->move_cleanup_count)
338			goto unlock;
339
340		if (!cpumask_test_cpu(me, &cfg->old_domain))
341			goto unlock;
342
343		spin_lock_irqsave(&vector_lock, flags);
344		__this_cpu_write(vector_irq[vector], -1);
345		cpumask_clear_cpu(me, &vector_table[vector]);
346		spin_unlock_irqrestore(&vector_lock, flags);
347		cfg->move_cleanup_count--;
348	unlock:
349		raw_spin_unlock(&desc->lock);
350	}
351	return IRQ_HANDLED;
352}
353
 
 
 
 
 
 
354static int __init parse_vector_domain(char *arg)
355{
356	if (!arg)
357		return -EINVAL;
358	if (!strcmp(arg, "percpu")) {
359		vector_domain_type = VECTOR_DOMAIN_PERCPU;
360		no_int_routing = 1;
361	}
362	return 0;
363}
364early_param("vector", parse_vector_domain);
365#else
366static cpumask_t vector_allocation_domain(int cpu)
367{
368	return CPU_MASK_ALL;
369}
370#endif
371
372
373void destroy_and_reserve_irq(unsigned int irq)
374{
375	unsigned long flags;
376
377	irq_init_desc(irq);
 
378	spin_lock_irqsave(&vector_lock, flags);
379	__clear_irq_vector(irq);
380	irq_status[irq] = IRQ_RSVD;
381	spin_unlock_irqrestore(&vector_lock, flags);
382}
383
384/*
385 * Dynamic irq allocate and deallocation for MSI
386 */
387int create_irq(void)
388{
389	unsigned long flags;
390	int irq, vector, cpu;
391	cpumask_t domain = CPU_MASK_NONE;
392
393	irq = vector = -ENOSPC;
394	spin_lock_irqsave(&vector_lock, flags);
395	for_each_online_cpu(cpu) {
396		domain = vector_allocation_domain(cpu);
397		vector = find_unassigned_vector(domain);
398		if (vector >= 0)
399			break;
400	}
401	if (vector < 0)
402		goto out;
403	irq = find_unassigned_irq();
404	if (irq < 0)
405		goto out;
406	BUG_ON(__bind_irq_vector(irq, vector, domain));
407 out:
408	spin_unlock_irqrestore(&vector_lock, flags);
409	if (irq >= 0)
410		irq_init_desc(irq);
411	return irq;
412}
413
414void destroy_irq(unsigned int irq)
415{
416	irq_init_desc(irq);
417	clear_irq_vector(irq);
418}
419
420#ifdef CONFIG_SMP
421#	define IS_RESCHEDULE(vec)	(vec == IA64_IPI_RESCHEDULE)
422#	define IS_LOCAL_TLB_FLUSH(vec)	(vec == IA64_IPI_LOCAL_TLB_FLUSH)
423#else
424#	define IS_RESCHEDULE(vec)	(0)
425#	define IS_LOCAL_TLB_FLUSH(vec)	(0)
426#endif
427/*
428 * That's where the IVT branches when we get an external
429 * interrupt. This branches to the correct hardware IRQ handler via
430 * function ptr.
431 */
432void
433ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
434{
435	struct pt_regs *old_regs = set_irq_regs(regs);
436	unsigned long saved_tpr;
437
438#if IRQ_DEBUG
439	{
440		unsigned long bsp, sp;
441
442		/*
443		 * Note: if the interrupt happened while executing in
444		 * the context switch routine (ia64_switch_to), we may
445		 * get a spurious stack overflow here.  This is
446		 * because the register and the memory stack are not
447		 * switched atomically.
448		 */
449		bsp = ia64_getreg(_IA64_REG_AR_BSP);
450		sp = ia64_getreg(_IA64_REG_SP);
451
452		if ((sp - bsp) < 1024) {
453			static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
454
455			if (__ratelimit(&ratelimit)) {
456				printk("ia64_handle_irq: DANGER: less than "
457				       "1KB of free stack space!!\n"
458				       "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
459			}
460		}
461	}
462#endif /* IRQ_DEBUG */
463
464	/*
465	 * Always set TPR to limit maximum interrupt nesting depth to
466	 * 16 (without this, it would be ~240, which could easily lead
467	 * to kernel stack overflows).
468	 */
469	irq_enter();
470	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
471	ia64_srlz_d();
472	while (vector != IA64_SPURIOUS_INT_VECTOR) {
473		int irq = local_vector_to_irq(vector);
 
474
475		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
476			smp_local_flush_tlb();
477			kstat_incr_irq_this_cpu(irq);
478		} else if (unlikely(IS_RESCHEDULE(vector))) {
479			scheduler_ipi();
480			kstat_incr_irq_this_cpu(irq);
481		} else {
482			ia64_setreg(_IA64_REG_CR_TPR, vector);
483			ia64_srlz_d();
484
485			if (unlikely(irq < 0)) {
486				printk(KERN_ERR "%s: Unexpected interrupt "
487				       "vector %d on CPU %d is not mapped "
488				       "to any IRQ!\n", __func__, vector,
489				       smp_processor_id());
490			} else
491				generic_handle_irq(irq);
492
493			/*
494			 * Disable interrupts and send EOI:
495			 */
496			local_irq_disable();
497			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
498		}
499		ia64_eoi();
500		vector = ia64_get_ivr();
501	}
502	/*
503	 * This must be done *after* the ia64_eoi().  For example, the keyboard softirq
504	 * handler needs to be able to wait for further keyboard interrupts, which can't
505	 * come through until ia64_eoi() has been done.
506	 */
507	irq_exit();
508	set_irq_regs(old_regs);
509}
510
511#ifdef CONFIG_HOTPLUG_CPU
512/*
513 * This function emulates a interrupt processing when a cpu is about to be
514 * brought down.
515 */
516void ia64_process_pending_intr(void)
517{
518	ia64_vector vector;
519	unsigned long saved_tpr;
520	extern unsigned int vectors_in_migration[NR_IRQS];
521
522	vector = ia64_get_ivr();
523
524	irq_enter();
525	saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
526	ia64_srlz_d();
527
528	 /*
529	  * Perform normal interrupt style processing
530	  */
531	while (vector != IA64_SPURIOUS_INT_VECTOR) {
532		int irq = local_vector_to_irq(vector);
 
533
534		if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
535			smp_local_flush_tlb();
536			kstat_incr_irq_this_cpu(irq);
537		} else if (unlikely(IS_RESCHEDULE(vector))) {
538			kstat_incr_irq_this_cpu(irq);
539		} else {
540			struct pt_regs *old_regs = set_irq_regs(NULL);
541
542			ia64_setreg(_IA64_REG_CR_TPR, vector);
543			ia64_srlz_d();
544
545			/*
546			 * Now try calling normal ia64_handle_irq as it would have got called
547			 * from a real intr handler. Try passing null for pt_regs, hopefully
548			 * it will work. I hope it works!.
549			 * Probably could shared code.
550			 */
551			if (unlikely(irq < 0)) {
552				printk(KERN_ERR "%s: Unexpected interrupt "
553				       "vector %d on CPU %d not being mapped "
554				       "to any IRQ!!\n", __func__, vector,
555				       smp_processor_id());
556			} else {
557				vectors_in_migration[irq]=0;
558				generic_handle_irq(irq);
559			}
560			set_irq_regs(old_regs);
561
562			/*
563			 * Disable interrupts and send EOI
564			 */
565			local_irq_disable();
566			ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
567		}
568		ia64_eoi();
569		vector = ia64_get_ivr();
570	}
571	irq_exit();
572}
573#endif
574
575
576#ifdef CONFIG_SMP
577
578static irqreturn_t dummy_handler (int irq, void *dev_id)
579{
580	BUG();
581	return IRQ_NONE;
582}
583
 
 
 
 
 
 
584/*
585 * KVM uses this interrupt to force a cpu out of guest mode
586 */
 
 
 
 
 
 
 
 
 
 
 
587
588#endif
589
590void
591register_percpu_irq(ia64_vector vec, irq_handler_t handler, unsigned long flags,
592		    const char *name)
593{
594	unsigned int irq;
595
596	irq = vec;
597	BUG_ON(bind_irq_vector(irq, vec, CPU_MASK_ALL));
598	irq_set_status_flags(irq, IRQ_PER_CPU);
599	irq_set_chip(irq, &irq_type_ia64_lsapic);
600	if (handler)
601		if (request_irq(irq, handler, flags, name, NULL))
602			pr_err("Failed to request irq %u (%s)\n", irq, name);
603	irq_set_handler(irq, handle_percpu_irq);
604}
605
606void __init
607ia64_native_register_ipi(void)
608{
609#ifdef CONFIG_SMP
610	register_percpu_irq(IA64_IPI_VECTOR, handle_IPI, 0, "IPI");
611	register_percpu_irq(IA64_IPI_RESCHEDULE, dummy_handler, 0, "resched");
612	register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, dummy_handler, 0,
613			    "tlb_flush");
614#endif
615}
616
617void __init
618init_IRQ (void)
619{
 
620	acpi_boot_init();
 
621	ia64_register_ipi();
622	register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL, 0, NULL);
623#ifdef CONFIG_SMP
624	if (vector_domain_type != VECTOR_DOMAIN_NONE) {
625		register_percpu_irq(IA64_IRQ_MOVE_VECTOR,
626				    smp_irq_move_cleanup_interrupt, 0,
627				    "irq_move");
628	}
629#endif
630#ifdef CONFIG_PERFMON
631	pfm_init_percpu();
632#endif
 
633}
634
635void
636ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
637{
638	void __iomem *ipi_addr;
639	unsigned long ipi_data;
640	unsigned long phys_cpu_id;
641
642	phys_cpu_id = cpu_physical_id(cpu);
643
644	/*
645	 * cpu number is in 8bit ID and 8bit EID
646	 */
647
648	ipi_data = (delivery_mode << 8) | (vector & 0xff);
649	ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
650
651	writeq(ipi_data, ipi_addr);
652}