Merge branch 'x86-entry-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / arch / ia64 / kernel / irq_ia64.c
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
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
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
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
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
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
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
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
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
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  */
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
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
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
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
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
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
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
371 static cpumask_t vector_allocation_domain(int cpu)
372 {
373         return CPU_MASK_ALL;
374 }
375 #endif
376
377
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  */
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
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
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  */
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
583 static irqreturn_t dummy_handler (int irq, void *dev_id)
584 {
585         BUG();
586 }
587
588 static struct irqaction ipi_irqaction = {
589         .handler =      handle_IPI,
590         .name =         "IPI"
591 };
592
593 /*
594  * KVM uses this interrupt to force a cpu out of guest mode
595  */
596 static struct irqaction resched_irqaction = {
597         .handler =      dummy_handler,
598         .name =         "resched"
599 };
600
601 static struct irqaction tlb_irqaction = {
602         .handler =      dummy_handler,
603         .name =         "tlb_flush"
604 };
605
606 #endif
607
608 void
609 ia64_native_register_percpu_irq (ia64_vector vec, struct irqaction *action)
610 {
611         unsigned int irq;
612
613         irq = vec;
614         BUG_ON(bind_irq_vector(irq, vec, CPU_MASK_ALL));
615         irq_set_status_flags(irq, IRQ_PER_CPU);
616         irq_set_chip(irq, &irq_type_ia64_lsapic);
617         if (action)
618                 setup_irq(irq, action);
619         irq_set_handler(irq, handle_percpu_irq);
620 }
621
622 void __init
623 ia64_native_register_ipi(void)
624 {
625 #ifdef CONFIG_SMP
626         register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
627         register_percpu_irq(IA64_IPI_RESCHEDULE, &resched_irqaction);
628         register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &tlb_irqaction);
629 #endif
630 }
631
632 void __init
633 init_IRQ (void)
634 {
635         acpi_boot_init();
636         ia64_register_ipi();
637         register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
638 #ifdef CONFIG_SMP
639         if (vector_domain_type != VECTOR_DOMAIN_NONE)
640                 register_percpu_irq(IA64_IRQ_MOVE_VECTOR, &irq_move_irqaction);
641 #endif
642 #ifdef CONFIG_PERFMON
643         pfm_init_percpu();
644 #endif
645 }
646
647 void
648 ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
649 {
650         void __iomem *ipi_addr;
651         unsigned long ipi_data;
652         unsigned long phys_cpu_id;
653
654         phys_cpu_id = cpu_physical_id(cpu);
655
656         /*
657          * cpu number is in 8bit ID and 8bit EID
658          */
659
660         ipi_data = (delivery_mode << 8) | (vector & 0xff);
661         ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
662
663         writeq(ipi_data, ipi_addr);
664 }