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
20 #include <linux/jiffies.h>
21 #include <linux/errno.h>
22 #include <linux/init.h>
23 #include <linux/interrupt.h>
24 #include <linux/ioport.h>
25 #include <linux/kernel_stat.h>
26 #include <linux/ptrace.h>
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/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 int ia64_first_device_vector = IA64_DEF_FIRST_DEVICE_VECTOR;
56 int ia64_last_device_vector = IA64_DEF_LAST_DEVICE_VECTOR;
57
58 /* default base addr of IPI table */
59 void __iomem *ipi_base_addr = ((void __iomem *)
60 (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));
61
62 static 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 };
72 EXPORT_SYMBOL(isa_irq_to_vector_map);
73
74 DEFINE_SPINLOCK(vector_lock);
75
76 struct 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
83 DEFINE_PER_CPU(int[IA64_NUM_VECTORS], vector_irq) = {
84 [0 ... IA64_NUM_VECTORS - 1] = -1
85 };
86
87 static cpumask_t vector_table[IA64_NUM_VECTORS] = {
88 [0 ... IA64_NUM_VECTORS - 1] = CPU_MASK_NONE
89 };
90
91 static int irq_status[NR_IRQS] = {
92 [0 ... NR_IRQS -1] = IRQ_UNUSED
93 };
94
find_unassigned_irq(void)95 static 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
find_unassigned_vector(cpumask_t domain)105 static 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
__bind_irq_vector(int irq,int vector,cpumask_t domain)124 static 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
bind_irq_vector(int irq,int vector,cpumask_t domain)149 int 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
__clear_irq_vector(int irq)160 static 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
clear_irq_vector(int irq)178 static 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
187 int
ia64_native_assign_irq_vector(int irq)188 ia64_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
213 void
ia64_native_free_irq_vector(int vector)214 ia64_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
222 int
reserve_irq_vector(int vector)223 reserve_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 */
__setup_vector_irq(int cpu)235 void __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
253 static enum vector_domain_type {
254 VECTOR_DOMAIN_NONE,
255 VECTOR_DOMAIN_PERCPU
256 } vector_domain_type = VECTOR_DOMAIN_NONE;
257
vector_allocation_domain(int cpu)258 static 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
__irq_prepare_move(int irq,int cpu)265 static 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
irq_prepare_move(int irq,int cpu)289 int 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
irq_complete_move(unsigned irq)300 void 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
smp_irq_move_cleanup_interrupt(int irq,void * dev_id)319 static 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
354 static struct irqaction irq_move_irqaction = {
355 .handler = smp_irq_move_cleanup_interrupt,
356 .name = "irq_move"
357 };
358
parse_vector_domain(char * arg)359 static int __init parse_vector_domain(char *arg)
360 {
361 if (!arg)
362 return -EINVAL;
363 if (!strcmp(arg, "percpu")) {
364 vector_domain_type = VECTOR_DOMAIN_PERCPU;
365 no_int_routing = 1;
366 }
367 return 0;
368 }
369 early_param("vector", parse_vector_domain);
370 #else
vector_allocation_domain(int cpu)371 static cpumask_t vector_allocation_domain(int cpu)
372 {
373 return CPU_MASK_ALL;
374 }
375 #endif
376
377
destroy_and_reserve_irq(unsigned int irq)378 void destroy_and_reserve_irq(unsigned int irq)
379 {
380 unsigned long flags;
381
382 irq_init_desc(irq);
383 spin_lock_irqsave(&vector_lock, flags);
384 __clear_irq_vector(irq);
385 irq_status[irq] = IRQ_RSVD;
386 spin_unlock_irqrestore(&vector_lock, flags);
387 }
388
389 /*
390 * Dynamic irq allocate and deallocation for MSI
391 */
create_irq(void)392 int create_irq(void)
393 {
394 unsigned long flags;
395 int irq, vector, cpu;
396 cpumask_t domain = CPU_MASK_NONE;
397
398 irq = vector = -ENOSPC;
399 spin_lock_irqsave(&vector_lock, flags);
400 for_each_online_cpu(cpu) {
401 domain = vector_allocation_domain(cpu);
402 vector = find_unassigned_vector(domain);
403 if (vector >= 0)
404 break;
405 }
406 if (vector < 0)
407 goto out;
408 irq = find_unassigned_irq();
409 if (irq < 0)
410 goto out;
411 BUG_ON(__bind_irq_vector(irq, vector, domain));
412 out:
413 spin_unlock_irqrestore(&vector_lock, flags);
414 if (irq >= 0)
415 irq_init_desc(irq);
416 return irq;
417 }
418
destroy_irq(unsigned int irq)419 void destroy_irq(unsigned int irq)
420 {
421 irq_init_desc(irq);
422 clear_irq_vector(irq);
423 }
424
425 #ifdef CONFIG_SMP
426 # define IS_RESCHEDULE(vec) (vec == IA64_IPI_RESCHEDULE)
427 # define IS_LOCAL_TLB_FLUSH(vec) (vec == IA64_IPI_LOCAL_TLB_FLUSH)
428 #else
429 # define IS_RESCHEDULE(vec) (0)
430 # define IS_LOCAL_TLB_FLUSH(vec) (0)
431 #endif
432 /*
433 * That's where the IVT branches when we get an external
434 * interrupt. This branches to the correct hardware IRQ handler via
435 * function ptr.
436 */
437 void
ia64_handle_irq(ia64_vector vector,struct pt_regs * regs)438 ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
439 {
440 struct pt_regs *old_regs = set_irq_regs(regs);
441 unsigned long saved_tpr;
442
443 #if IRQ_DEBUG
444 {
445 unsigned long bsp, sp;
446
447 /*
448 * Note: if the interrupt happened while executing in
449 * the context switch routine (ia64_switch_to), we may
450 * get a spurious stack overflow here. This is
451 * because the register and the memory stack are not
452 * switched atomically.
453 */
454 bsp = ia64_getreg(_IA64_REG_AR_BSP);
455 sp = ia64_getreg(_IA64_REG_SP);
456
457 if ((sp - bsp) < 1024) {
458 static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
459
460 if (__ratelimit(&ratelimit)) {
461 printk("ia64_handle_irq: DANGER: less than "
462 "1KB of free stack space!!\n"
463 "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
464 }
465 }
466 }
467 #endif /* IRQ_DEBUG */
468
469 /*
470 * Always set TPR to limit maximum interrupt nesting depth to
471 * 16 (without this, it would be ~240, which could easily lead
472 * to kernel stack overflows).
473 */
474 irq_enter();
475 saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
476 ia64_srlz_d();
477 while (vector != IA64_SPURIOUS_INT_VECTOR) {
478 int irq = local_vector_to_irq(vector);
479
480 if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
481 smp_local_flush_tlb();
482 kstat_incr_irq_this_cpu(irq);
483 } else if (unlikely(IS_RESCHEDULE(vector))) {
484 scheduler_ipi();
485 kstat_incr_irq_this_cpu(irq);
486 } else {
487 ia64_setreg(_IA64_REG_CR_TPR, vector);
488 ia64_srlz_d();
489
490 if (unlikely(irq < 0)) {
491 printk(KERN_ERR "%s: Unexpected interrupt "
492 "vector %d on CPU %d is not mapped "
493 "to any IRQ!\n", __func__, vector,
494 smp_processor_id());
495 } else
496 generic_handle_irq(irq);
497
498 /*
499 * Disable interrupts and send EOI:
500 */
501 local_irq_disable();
502 ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
503 }
504 ia64_eoi();
505 vector = ia64_get_ivr();
506 }
507 /*
508 * This must be done *after* the ia64_eoi(). For example, the keyboard softirq
509 * handler needs to be able to wait for further keyboard interrupts, which can't
510 * come through until ia64_eoi() has been done.
511 */
512 irq_exit();
513 set_irq_regs(old_regs);
514 }
515
516 #ifdef CONFIG_HOTPLUG_CPU
517 /*
518 * This function emulates a interrupt processing when a cpu is about to be
519 * brought down.
520 */
ia64_process_pending_intr(void)521 void ia64_process_pending_intr(void)
522 {
523 ia64_vector vector;
524 unsigned long saved_tpr;
525 extern unsigned int vectors_in_migration[NR_IRQS];
526
527 vector = ia64_get_ivr();
528
529 irq_enter();
530 saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
531 ia64_srlz_d();
532
533 /*
534 * Perform normal interrupt style processing
535 */
536 while (vector != IA64_SPURIOUS_INT_VECTOR) {
537 int irq = local_vector_to_irq(vector);
538
539 if (unlikely(IS_LOCAL_TLB_FLUSH(vector))) {
540 smp_local_flush_tlb();
541 kstat_incr_irq_this_cpu(irq);
542 } else if (unlikely(IS_RESCHEDULE(vector))) {
543 kstat_incr_irq_this_cpu(irq);
544 } else {
545 struct pt_regs *old_regs = set_irq_regs(NULL);
546
547 ia64_setreg(_IA64_REG_CR_TPR, vector);
548 ia64_srlz_d();
549
550 /*
551 * Now try calling normal ia64_handle_irq as it would have got called
552 * from a real intr handler. Try passing null for pt_regs, hopefully
553 * it will work. I hope it works!.
554 * Probably could shared code.
555 */
556 if (unlikely(irq < 0)) {
557 printk(KERN_ERR "%s: Unexpected interrupt "
558 "vector %d on CPU %d not being mapped "
559 "to any IRQ!!\n", __func__, vector,
560 smp_processor_id());
561 } else {
562 vectors_in_migration[irq]=0;
563 generic_handle_irq(irq);
564 }
565 set_irq_regs(old_regs);
566
567 /*
568 * Disable interrupts and send EOI
569 */
570 local_irq_disable();
571 ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
572 }
573 ia64_eoi();
574 vector = ia64_get_ivr();
575 }
576 irq_exit();
577 }
578 #endif
579
580
581 #ifdef CONFIG_SMP
582
dummy_handler(int irq,void * dev_id)583 static irqreturn_t dummy_handler (int irq, void *dev_id)
584 {
585 BUG();
586 return IRQ_NONE;
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
ia64_native_register_percpu_irq(ia64_vector vec,struct irqaction * action)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
ia64_native_register_ipi(void)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
init_IRQ(void)634 init_IRQ (void)
635 {
636 acpi_boot_init();
637 ia64_register_ipi();
638 register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
639 #ifdef CONFIG_SMP
640 if (vector_domain_type != VECTOR_DOMAIN_NONE)
641 register_percpu_irq(IA64_IRQ_MOVE_VECTOR, &irq_move_irqaction);
642 #endif
643 #ifdef CONFIG_PERFMON
644 pfm_init_percpu();
645 #endif
646 }
647
648 void
ia64_send_ipi(int cpu,int vector,int delivery_mode,int redirect)649 ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
650 {
651 void __iomem *ipi_addr;
652 unsigned long ipi_data;
653 unsigned long phys_cpu_id;
654
655 phys_cpu_id = cpu_physical_id(cpu);
656
657 /*
658 * cpu number is in 8bit ID and 8bit EID
659 */
660
661 ipi_data = (delivery_mode << 8) | (vector & 0xff);
662 ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
663
664 writeq(ipi_data, ipi_addr);
665 }
666
