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1 /*
2  * I/O SAPIC support.
3  *
4  * Copyright (C) 1999 Intel Corp.
5  * Copyright (C) 1999 Asit Mallick <asit.k.mallick@intel.com>
6  * Copyright (C) 2000-2002 J.I. Lee <jung-ik.lee@intel.com>
7  * Copyright (C) 1999-2000, 2002-2003 Hewlett-Packard Co.
8  *      David Mosberger-Tang <davidm@hpl.hp.com>
9  * Copyright (C) 1999 VA Linux Systems
10  * Copyright (C) 1999,2000 Walt Drummond <drummond@valinux.com>
11  *
12  * 00/04/19     D. Mosberger    Rewritten to mirror more closely the x86 I/O APIC code.
13  *                              In particular, we now have separate handlers for edge
14  *                              and level triggered interrupts.
15  * 00/10/27     Asit Mallick, Goutham Rao <goutham.rao@intel.com> IRQ vector allocation
16  *                              PCI to vector mapping, shared PCI interrupts.
17  * 00/10/27     D. Mosberger    Document things a bit more to make them more understandable.
18  *                              Clean up much of the old IOSAPIC cruft.
19  * 01/07/27     J.I. Lee        PCI irq routing, Platform/Legacy interrupts and fixes for
20  *                              ACPI S5(SoftOff) support.
21  * 02/01/23     J.I. Lee        iosapic pgm fixes for PCI irq routing from _PRT
22  * 02/01/07     E. Focht        <efocht@ess.nec.de> Redirectable interrupt vectors in
23  *                              iosapic_set_affinity(), initializations for
24  *                              /proc/irq/#/smp_affinity
25  * 02/04/02     P. Diefenbaugh  Cleaned up ACPI PCI IRQ routing.
26  * 02/04/18     J.I. Lee        bug fix in iosapic_init_pci_irq
27  * 02/04/30     J.I. Lee        bug fix in find_iosapic to fix ACPI PCI IRQ to IOSAPIC mapping
28  *                              error
29  * 02/07/29     T. Kochi        Allocate interrupt vectors dynamically
30  * 02/08/04     T. Kochi        Cleaned up terminology (irq, global system interrupt, vector, etc.)
31  * 02/09/20     D. Mosberger    Simplified by taking advantage of ACPI's pci_irq code.
32  * 03/02/19     B. Helgaas      Make pcat_compat system-wide, not per-IOSAPIC.
33  *                              Remove iosapic_address & gsi_base from external interfaces.
34  *                              Rationalize __init/__devinit attributes.
35  * 04/12/04 Ashok Raj   <ashok.raj@intel.com> Intel Corporation 2004
36  *                              Updated to work with irq migration necessary for CPU Hotplug
37  */
38 /*
39  * Here is what the interrupt logic between a PCI device and the kernel looks like:
40  *
41  * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC, INTD).  The
42  *     device is uniquely identified by its bus--, and slot-number (the function
43  *     number does not matter here because all functions share the same interrupt
44  *     lines).
45  *
46  * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC controller.
47  *     Multiple interrupt lines may have to share the same IOSAPIC pin (if they're level
48  *     triggered and use the same polarity).  Each interrupt line has a unique Global
49  *     System Interrupt (GSI) number which can be calculated as the sum of the controller's
50  *     base GSI number and the IOSAPIC pin number to which the line connects.
51  *
52  * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the IOSAPIC pin
53  *     into the IA-64 interrupt vector.  This interrupt vector is then sent to the CPU.
54  *
55  * (4) The kernel recognizes an interrupt as an IRQ.  The IRQ interface is used as
56  *     architecture-independent interrupt handling mechanism in Linux.  As an
57  *     IRQ is a number, we have to have IA-64 interrupt vector number <-> IRQ number
58  *     mapping.  On smaller systems, we use one-to-one mapping between IA-64 vector and
59  *     IRQ.  A platform can implement platform_irq_to_vector(irq) and
60  *     platform_local_vector_to_irq(vector) APIs to differentiate the mapping.
61  *     Please see also include/asm-ia64/hw_irq.h for those APIs.
62  *
63  * To sum up, there are three levels of mappings involved:
64  *
65  *      PCI pin -> global system interrupt (GSI) -> IA-64 vector <-> IRQ
66  *
67  * Note: The term "IRQ" is loosely used everywhere in Linux kernel to describe interrupts.
68  * Now we use "IRQ" only for Linux IRQ's.  ISA IRQ (isa_irq) is the only exception in this
69  * source code.
70  */
71 #include <linux/config.h>
72
73 #include <linux/acpi.h>
74 #include <linux/init.h>
75 #include <linux/irq.h>
76 #include <linux/kernel.h>
77 #include <linux/list.h>
78 #include <linux/pci.h>
79 #include <linux/smp.h>
80 #include <linux/smp_lock.h>
81 #include <linux/string.h>
82
83 #include <asm/delay.h>
84 #include <asm/hw_irq.h>
85 #include <asm/io.h>
86 #include <asm/iosapic.h>
87 #include <asm/machvec.h>
88 #include <asm/processor.h>
89 #include <asm/ptrace.h>
90 #include <asm/system.h>
91
92
93 #undef DEBUG_INTERRUPT_ROUTING
94
95 #ifdef DEBUG_INTERRUPT_ROUTING
96 #define DBG(fmt...)     printk(fmt)
97 #else
98 #define DBG(fmt...)
99 #endif
100
101 static DEFINE_SPINLOCK(iosapic_lock);
102
103 /* These tables map IA-64 vectors to the IOSAPIC pin that generates this vector. */
104
105 static struct iosapic_intr_info {
106         char __iomem    *addr;          /* base address of IOSAPIC */
107         u32             low32;          /* current value of low word of Redirection table entry */
108         unsigned int    gsi_base;       /* first GSI assigned to this IOSAPIC */
109         char            rte_index;      /* IOSAPIC RTE index (-1 => not an IOSAPIC interrupt) */
110         unsigned char   dmode   : 3;    /* delivery mode (see iosapic.h) */
111         unsigned char   polarity: 1;    /* interrupt polarity (see iosapic.h) */
112         unsigned char   trigger : 1;    /* trigger mode (see iosapic.h) */
113         int             refcnt;         /* reference counter */
114 } iosapic_intr_info[IA64_NUM_VECTORS];
115
116 static struct iosapic {
117         char __iomem    *addr;          /* base address of IOSAPIC */
118         unsigned int    gsi_base;       /* first GSI assigned to this IOSAPIC */
119         unsigned short  num_rte;        /* number of RTE in this IOSAPIC */
120 #ifdef CONFIG_NUMA
121         unsigned short  node;           /* numa node association via pxm */
122 #endif
123 } iosapic_lists[NR_IOSAPICS];
124
125 static int num_iosapic;
126
127 static unsigned char pcat_compat __initdata;    /* 8259 compatibility flag */
128
129
130 /*
131  * Find an IOSAPIC associated with a GSI
132  */
133 static inline int
134 find_iosapic (unsigned int gsi)
135 {
136         int i;
137
138         for (i = 0; i < num_iosapic; i++) {
139                 if ((unsigned) (gsi - iosapic_lists[i].gsi_base) < iosapic_lists[i].num_rte)
140                         return i;
141         }
142
143         return -1;
144 }
145
146 static inline int
147 _gsi_to_vector (unsigned int gsi)
148 {
149         struct iosapic_intr_info *info;
150
151         for (info = iosapic_intr_info; info < iosapic_intr_info + IA64_NUM_VECTORS; ++info)
152                 if (info->gsi_base + info->rte_index == gsi)
153                         return info - iosapic_intr_info;
154         return -1;
155 }
156
157 /*
158  * Translate GSI number to the corresponding IA-64 interrupt vector.  If no
159  * entry exists, return -1.
160  */
161 inline int
162 gsi_to_vector (unsigned int gsi)
163 {
164         return _gsi_to_vector(gsi);
165 }
166
167 int
168 gsi_to_irq (unsigned int gsi)
169 {
170         /*
171          * XXX fix me: this assumes an identity mapping vetween IA-64 vector and Linux irq
172          * numbers...
173          */
174         return _gsi_to_vector(gsi);
175 }
176
177 static void
178 set_rte (unsigned int vector, unsigned int dest, int mask)
179 {
180         unsigned long pol, trigger, dmode;
181         u32 low32, high32;
182         char __iomem *addr;
183         int rte_index;
184         char redir;
185
186         DBG(KERN_DEBUG"IOSAPIC: routing vector %d to 0x%x\n", vector, dest);
187
188         rte_index = iosapic_intr_info[vector].rte_index;
189         if (rte_index < 0)
190                 return;         /* not an IOSAPIC interrupt */
191
192         addr    = iosapic_intr_info[vector].addr;
193         pol     = iosapic_intr_info[vector].polarity;
194         trigger = iosapic_intr_info[vector].trigger;
195         dmode   = iosapic_intr_info[vector].dmode;
196         vector &= (~IA64_IRQ_REDIRECTED);
197
198         redir = (dmode == IOSAPIC_LOWEST_PRIORITY) ? 1 : 0;
199
200 #ifdef CONFIG_SMP
201         {
202                 unsigned int irq;
203
204                 for (irq = 0; irq < NR_IRQS; ++irq)
205                         if (irq_to_vector(irq) == vector) {
206                                 set_irq_affinity_info(irq, (int)(dest & 0xffff), redir);
207                                 break;
208                         }
209         }
210 #endif
211
212         low32 = ((pol << IOSAPIC_POLARITY_SHIFT) |
213                  (trigger << IOSAPIC_TRIGGER_SHIFT) |
214                  (dmode << IOSAPIC_DELIVERY_SHIFT) |
215                  ((mask ? 1 : 0) << IOSAPIC_MASK_SHIFT) |
216                  vector);
217
218         /* dest contains both id and eid */
219         high32 = (dest << IOSAPIC_DEST_SHIFT);
220
221         iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
222         iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
223         iosapic_intr_info[vector].low32 = low32;
224 }
225
226 static void
227 nop (unsigned int vector)
228 {
229         /* do nothing... */
230 }
231
232 static void
233 mask_irq (unsigned int irq)
234 {
235         unsigned long flags;
236         char __iomem *addr;
237         u32 low32;
238         int rte_index;
239         ia64_vector vec = irq_to_vector(irq);
240
241         addr = iosapic_intr_info[vec].addr;
242         rte_index = iosapic_intr_info[vec].rte_index;
243
244         if (rte_index < 0)
245                 return;                 /* not an IOSAPIC interrupt! */
246
247         spin_lock_irqsave(&iosapic_lock, flags);
248         {
249                 /* set only the mask bit */
250                 low32 = iosapic_intr_info[vec].low32 |= IOSAPIC_MASK;
251                 iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
252         }
253         spin_unlock_irqrestore(&iosapic_lock, flags);
254 }
255
256 static void
257 unmask_irq (unsigned int irq)
258 {
259         unsigned long flags;
260         char __iomem *addr;
261         u32 low32;
262         int rte_index;
263         ia64_vector vec = irq_to_vector(irq);
264
265         addr = iosapic_intr_info[vec].addr;
266         rte_index = iosapic_intr_info[vec].rte_index;
267         if (rte_index < 0)
268                 return;                 /* not an IOSAPIC interrupt! */
269
270         spin_lock_irqsave(&iosapic_lock, flags);
271         {
272                 low32 = iosapic_intr_info[vec].low32 &= ~IOSAPIC_MASK;
273                 iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
274         }
275         spin_unlock_irqrestore(&iosapic_lock, flags);
276 }
277
278
279 static void
280 iosapic_set_affinity (unsigned int irq, cpumask_t mask)
281 {
282 #ifdef CONFIG_SMP
283         unsigned long flags;
284         u32 high32, low32;
285         int dest, rte_index;
286         char __iomem *addr;
287         int redir = (irq & IA64_IRQ_REDIRECTED) ? 1 : 0;
288         ia64_vector vec;
289
290         irq &= (~IA64_IRQ_REDIRECTED);
291         vec = irq_to_vector(irq);
292
293         if (cpus_empty(mask))
294                 return;
295
296         dest = cpu_physical_id(first_cpu(mask));
297
298         rte_index = iosapic_intr_info[vec].rte_index;
299         addr = iosapic_intr_info[vec].addr;
300
301         if (rte_index < 0)
302                 return;                 /* not an IOSAPIC interrupt */
303
304         set_irq_affinity_info(irq, dest, redir);
305
306         /* dest contains both id and eid */
307         high32 = dest << IOSAPIC_DEST_SHIFT;
308
309         spin_lock_irqsave(&iosapic_lock, flags);
310         {
311                 low32 = iosapic_intr_info[vec].low32 & ~(7 << IOSAPIC_DELIVERY_SHIFT);
312
313                 if (redir)
314                         /* change delivery mode to lowest priority */
315                         low32 |= (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
316                 else
317                         /* change delivery mode to fixed */
318                         low32 |= (IOSAPIC_FIXED << IOSAPIC_DELIVERY_SHIFT);
319
320                 iosapic_intr_info[vec].low32 = low32;
321                 iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
322                 iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
323         }
324         spin_unlock_irqrestore(&iosapic_lock, flags);
325 #endif
326 }
327
328 /*
329  * Handlers for level-triggered interrupts.
330  */
331
332 static unsigned int
333 iosapic_startup_level_irq (unsigned int irq)
334 {
335         unmask_irq(irq);
336         return 0;
337 }
338
339 static void
340 iosapic_end_level_irq (unsigned int irq)
341 {
342         ia64_vector vec = irq_to_vector(irq);
343
344         move_irq(irq);
345         iosapic_eoi(iosapic_intr_info[vec].addr, vec);
346 }
347
348 #define iosapic_shutdown_level_irq      mask_irq
349 #define iosapic_enable_level_irq        unmask_irq
350 #define iosapic_disable_level_irq       mask_irq
351 #define iosapic_ack_level_irq           nop
352
353 struct hw_interrupt_type irq_type_iosapic_level = {
354         .typename =     "IO-SAPIC-level",
355         .startup =      iosapic_startup_level_irq,
356         .shutdown =     iosapic_shutdown_level_irq,
357         .enable =       iosapic_enable_level_irq,
358         .disable =      iosapic_disable_level_irq,
359         .ack =          iosapic_ack_level_irq,
360         .end =          iosapic_end_level_irq,
361         .set_affinity = iosapic_set_affinity
362 };
363
364 /*
365  * Handlers for edge-triggered interrupts.
366  */
367
368 static unsigned int
369 iosapic_startup_edge_irq (unsigned int irq)
370 {
371         unmask_irq(irq);
372         /*
373          * IOSAPIC simply drops interrupts pended while the
374          * corresponding pin was masked, so we can't know if an
375          * interrupt is pending already.  Let's hope not...
376          */
377         return 0;
378 }
379
380 static void
381 iosapic_ack_edge_irq (unsigned int irq)
382 {
383         irq_desc_t *idesc = irq_descp(irq);
384
385         move_irq(irq);
386         /*
387          * Once we have recorded IRQ_PENDING already, we can mask the
388          * interrupt for real. This prevents IRQ storms from unhandled
389          * devices.
390          */
391         if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) == (IRQ_PENDING|IRQ_DISABLED))
392                 mask_irq(irq);
393 }
394
395 #define iosapic_enable_edge_irq         unmask_irq
396 #define iosapic_disable_edge_irq        nop
397 #define iosapic_end_edge_irq            nop
398
399 struct hw_interrupt_type irq_type_iosapic_edge = {
400         .typename =     "IO-SAPIC-edge",
401         .startup =      iosapic_startup_edge_irq,
402         .shutdown =     iosapic_disable_edge_irq,
403         .enable =       iosapic_enable_edge_irq,
404         .disable =      iosapic_disable_edge_irq,
405         .ack =          iosapic_ack_edge_irq,
406         .end =          iosapic_end_edge_irq,
407         .set_affinity = iosapic_set_affinity
408 };
409
410 unsigned int
411 iosapic_version (char __iomem *addr)
412 {
413         /*
414          * IOSAPIC Version Register return 32 bit structure like:
415          * {
416          *      unsigned int version   : 8;
417          *      unsigned int reserved1 : 8;
418          *      unsigned int max_redir : 8;
419          *      unsigned int reserved2 : 8;
420          * }
421          */
422         return iosapic_read(addr, IOSAPIC_VERSION);
423 }
424
425 /*
426  * if the given vector is already owned by other,
427  *  assign a new vector for the other and make the vector available
428  */
429 static void __init
430 iosapic_reassign_vector (int vector)
431 {
432         int new_vector;
433
434         if (iosapic_intr_info[vector].rte_index >= 0 || iosapic_intr_info[vector].addr
435             || iosapic_intr_info[vector].gsi_base || iosapic_intr_info[vector].dmode
436             || iosapic_intr_info[vector].polarity || iosapic_intr_info[vector].trigger)
437         {
438                 new_vector = assign_irq_vector(AUTO_ASSIGN);
439                 printk(KERN_INFO "Reassigning vector %d to %d\n", vector, new_vector);
440                 memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector],
441                        sizeof(struct iosapic_intr_info));
442                 memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
443                 iosapic_intr_info[vector].rte_index = -1;
444         }
445 }
446
447 static void
448 register_intr (unsigned int gsi, int vector, unsigned char delivery,
449                unsigned long polarity, unsigned long trigger)
450 {
451         irq_desc_t *idesc;
452         struct hw_interrupt_type *irq_type;
453         int rte_index;
454         int index;
455         unsigned long gsi_base;
456         void __iomem *iosapic_address;
457
458         index = find_iosapic(gsi);
459         if (index < 0) {
460                 printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n", __FUNCTION__, gsi);
461                 return;
462         }
463
464         iosapic_address = iosapic_lists[index].addr;
465         gsi_base = iosapic_lists[index].gsi_base;
466
467         rte_index = gsi - gsi_base;
468         iosapic_intr_info[vector].rte_index = rte_index;
469         iosapic_intr_info[vector].polarity = polarity;
470         iosapic_intr_info[vector].dmode    = delivery;
471         iosapic_intr_info[vector].addr     = iosapic_address;
472         iosapic_intr_info[vector].gsi_base = gsi_base;
473         iosapic_intr_info[vector].trigger  = trigger;
474         iosapic_intr_info[vector].refcnt++;
475
476         if (trigger == IOSAPIC_EDGE)
477                 irq_type = &irq_type_iosapic_edge;
478         else
479                 irq_type = &irq_type_iosapic_level;
480
481         idesc = irq_descp(vector);
482         if (idesc->handler != irq_type) {
483                 if (idesc->handler != &no_irq_type)
484                         printk(KERN_WARNING "%s: changing vector %d from %s to %s\n",
485                                __FUNCTION__, vector, idesc->handler->typename, irq_type->typename);
486                 idesc->handler = irq_type;
487         }
488 }
489
490 static unsigned int
491 get_target_cpu (unsigned int gsi, int vector)
492 {
493 #ifdef CONFIG_SMP
494         static int cpu = -1;
495
496         /*
497          * If the platform supports redirection via XTP, let it
498          * distribute interrupts.
499          */
500         if (smp_int_redirect & SMP_IRQ_REDIRECTION)
501                 return cpu_physical_id(smp_processor_id());
502
503         /*
504          * Some interrupts (ACPI SCI, for instance) are registered
505          * before the BSP is marked as online.
506          */
507         if (!cpu_online(smp_processor_id()))
508                 return cpu_physical_id(smp_processor_id());
509
510 #ifdef CONFIG_NUMA
511         {
512                 int num_cpus, cpu_index, iosapic_index, numa_cpu, i = 0;
513                 cpumask_t cpu_mask;
514
515                 iosapic_index = find_iosapic(gsi);
516                 if (iosapic_index < 0 ||
517                     iosapic_lists[iosapic_index].node == MAX_NUMNODES)
518                         goto skip_numa_setup;
519
520                 cpu_mask = node_to_cpumask(iosapic_lists[iosapic_index].node);
521
522                 for_each_cpu_mask(numa_cpu, cpu_mask) {
523                         if (!cpu_online(numa_cpu))
524                                 cpu_clear(numa_cpu, cpu_mask);
525                 }
526
527                 num_cpus = cpus_weight(cpu_mask);
528
529                 if (!num_cpus)
530                         goto skip_numa_setup;
531
532                 /* Use vector assigment to distribute across cpus in node */
533                 cpu_index = vector % num_cpus;
534
535                 for (numa_cpu = first_cpu(cpu_mask) ; i < cpu_index ; i++)
536                         numa_cpu = next_cpu(numa_cpu, cpu_mask);
537
538                 if (numa_cpu != NR_CPUS)
539                         return cpu_physical_id(numa_cpu);
540         }
541 skip_numa_setup:
542 #endif
543         /*
544          * Otherwise, round-robin interrupt vectors across all the
545          * processors.  (It'd be nice if we could be smarter in the
546          * case of NUMA.)
547          */
548         do {
549                 if (++cpu >= NR_CPUS)
550                         cpu = 0;
551         } while (!cpu_online(cpu));
552
553         return cpu_physical_id(cpu);
554 #else
555         return cpu_physical_id(smp_processor_id());
556 #endif
557 }
558
559 /*
560  * ACPI can describe IOSAPIC interrupts via static tables and namespace
561  * methods.  This provides an interface to register those interrupts and
562  * program the IOSAPIC RTE.
563  */
564 int
565 iosapic_register_intr (unsigned int gsi,
566                        unsigned long polarity, unsigned long trigger)
567 {
568         int vector;
569         unsigned int dest;
570         unsigned long flags;
571
572         /*
573          * If this GSI has already been registered (i.e., it's a
574          * shared interrupt, or we lost a race to register it),
575          * don't touch the RTE.
576          */
577         spin_lock_irqsave(&iosapic_lock, flags);
578         {
579                 vector = gsi_to_vector(gsi);
580                 if (vector > 0) {
581                         iosapic_intr_info[vector].refcnt++;
582                         spin_unlock_irqrestore(&iosapic_lock, flags);
583                         return vector;
584                 }
585
586                 vector = assign_irq_vector(AUTO_ASSIGN);
587                 dest = get_target_cpu(gsi, vector);
588                 register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
589                         polarity, trigger);
590
591                 set_rte(vector, dest, 1);
592         }
593         spin_unlock_irqrestore(&iosapic_lock, flags);
594
595         printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
596                gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
597                (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
598                cpu_logical_id(dest), dest, vector);
599
600         return vector;
601 }
602
603 #ifdef CONFIG_ACPI_DEALLOCATE_IRQ
604 void
605 iosapic_unregister_intr (unsigned int gsi)
606 {
607         unsigned long flags;
608         int irq, vector;
609         irq_desc_t *idesc;
610         int rte_index;
611         unsigned long trigger, polarity;
612
613         /*
614          * If the irq associated with the gsi is not found,
615          * iosapic_unregister_intr() is unbalanced. We need to check
616          * this again after getting locks.
617          */
618         irq = gsi_to_irq(gsi);
619         if (irq < 0) {
620                 printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
621                 WARN_ON(1);
622                 return;
623         }
624         vector = irq_to_vector(irq);
625
626         idesc = irq_descp(irq);
627         spin_lock_irqsave(&idesc->lock, flags);
628         spin_lock(&iosapic_lock);
629         {
630                 rte_index = iosapic_intr_info[vector].rte_index;
631                 if (rte_index < 0) {
632                         spin_unlock(&iosapic_lock);
633                         spin_unlock_irqrestore(&idesc->lock, flags);
634                         printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
635                         WARN_ON(1);
636                         return;
637                 }
638
639                 if (--iosapic_intr_info[vector].refcnt > 0) {
640                         spin_unlock(&iosapic_lock);
641                         spin_unlock_irqrestore(&idesc->lock, flags);
642                         return;
643                 }
644
645                 /*
646                  * If interrupt handlers still exist on the irq
647                  * associated with the gsi, don't unregister the
648                  * interrupt.
649                  */
650                 if (idesc->action) {
651                         iosapic_intr_info[vector].refcnt++;
652                         spin_unlock(&iosapic_lock);
653                         spin_unlock_irqrestore(&idesc->lock, flags);
654                         printk(KERN_WARNING "Cannot unregister GSI. IRQ %u is still in use.\n", irq);
655                         return;
656                 }
657
658                 /* Clear the interrupt controller descriptor. */
659                 idesc->handler = &no_irq_type;
660
661                 trigger  = iosapic_intr_info[vector].trigger;
662                 polarity = iosapic_intr_info[vector].polarity;
663
664                 /* Clear the interrupt information. */
665                 memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
666                 iosapic_intr_info[vector].rte_index = -1;       /* mark as unused */
667         }
668         spin_unlock(&iosapic_lock);
669         spin_unlock_irqrestore(&idesc->lock, flags);
670
671         /* Free the interrupt vector */
672         free_irq_vector(vector);
673
674         printk(KERN_INFO "GSI %u (%s, %s) -> vector %d unregisterd.\n",
675                gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
676                (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
677                vector);
678 }
679 #endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
680
681 /*
682  * ACPI calls this when it finds an entry for a platform interrupt.
683  * Note that the irq_base and IOSAPIC address must be set in iosapic_init().
684  */
685 int __init
686 iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
687                                 int iosapic_vector, u16 eid, u16 id,
688                                 unsigned long polarity, unsigned long trigger)
689 {
690         static const char * const name[] = {"unknown", "PMI", "INIT", "CPEI"};
691         unsigned char delivery;
692         int vector, mask = 0;
693         unsigned int dest = ((id << 8) | eid) & 0xffff;
694
695         switch (int_type) {
696               case ACPI_INTERRUPT_PMI:
697                 vector = iosapic_vector;
698                 /*
699                  * since PMI vector is alloc'd by FW(ACPI) not by kernel,
700                  * we need to make sure the vector is available
701                  */
702                 iosapic_reassign_vector(vector);
703                 delivery = IOSAPIC_PMI;
704                 break;
705               case ACPI_INTERRUPT_INIT:
706                 vector = assign_irq_vector(AUTO_ASSIGN);
707                 delivery = IOSAPIC_INIT;
708                 break;
709               case ACPI_INTERRUPT_CPEI:
710                 vector = IA64_CPE_VECTOR;
711                 delivery = IOSAPIC_LOWEST_PRIORITY;
712                 mask = 1;
713                 break;
714               default:
715                 printk(KERN_ERR "iosapic_register_platform_irq(): invalid int type 0x%x\n", int_type);
716                 return -1;
717         }
718
719         register_intr(gsi, vector, delivery, polarity, trigger);
720
721         printk(KERN_INFO "PLATFORM int %s (0x%x): GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
722                int_type < ARRAY_SIZE(name) ? name[int_type] : "unknown",
723                int_type, gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
724                (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
725                cpu_logical_id(dest), dest, vector);
726
727         set_rte(vector, dest, mask);
728         return vector;
729 }
730
731
732 /*
733  * ACPI calls this when it finds an entry for a legacy ISA IRQ override.
734  * Note that the gsi_base and IOSAPIC address must be set in iosapic_init().
735  */
736 void __init
737 iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
738                           unsigned long polarity,
739                           unsigned long trigger)
740 {
741         int vector;
742         unsigned int dest = cpu_physical_id(smp_processor_id());
743
744         vector = isa_irq_to_vector(isa_irq);
745
746         register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY, polarity, trigger);
747
748         DBG("ISA: IRQ %u -> GSI %u (%s,%s) -> CPU %d (0x%04x) vector %d\n",
749             isa_irq, gsi, trigger == IOSAPIC_EDGE ? "edge" : "level",
750             polarity == IOSAPIC_POL_HIGH ? "high" : "low",
751             cpu_logical_id(dest), dest, vector);
752
753         set_rte(vector, dest, 1);
754 }
755
756 void __init
757 iosapic_system_init (int system_pcat_compat)
758 {
759         int vector;
760
761         for (vector = 0; vector < IA64_NUM_VECTORS; ++vector)
762                 iosapic_intr_info[vector].rte_index = -1;       /* mark as unused */
763
764         pcat_compat = system_pcat_compat;
765         if (pcat_compat) {
766                 /*
767                  * Disable the compatibility mode interrupts (8259 style), needs IN/OUT support
768                  * enabled.
769                  */
770                 printk(KERN_INFO "%s: Disabling PC-AT compatible 8259 interrupts\n", __FUNCTION__);
771                 outb(0xff, 0xA1);
772                 outb(0xff, 0x21);
773         }
774 }
775
776 void __init
777 iosapic_init (unsigned long phys_addr, unsigned int gsi_base)
778 {
779         int num_rte;
780         unsigned int isa_irq, ver;
781         char __iomem *addr;
782
783         addr = ioremap(phys_addr, 0);
784         ver = iosapic_version(addr);
785
786         /*
787          * The MAX_REDIR register holds the highest input pin
788          * number (starting from 0).
789          * We add 1 so that we can use it for number of pins (= RTEs)
790          */
791         num_rte = ((ver >> 16) & 0xff) + 1;
792
793         iosapic_lists[num_iosapic].addr = addr;
794         iosapic_lists[num_iosapic].gsi_base = gsi_base;
795         iosapic_lists[num_iosapic].num_rte = num_rte;
796 #ifdef CONFIG_NUMA
797         iosapic_lists[num_iosapic].node = MAX_NUMNODES;
798 #endif
799         num_iosapic++;
800
801         if ((gsi_base == 0) && pcat_compat) {
802                 /*
803                  * Map the legacy ISA devices into the IOSAPIC data.  Some of these may
804                  * get reprogrammed later on with data from the ACPI Interrupt Source
805                  * Override table.
806                  */
807                 for (isa_irq = 0; isa_irq < 16; ++isa_irq)
808                         iosapic_override_isa_irq(isa_irq, isa_irq, IOSAPIC_POL_HIGH, IOSAPIC_EDGE);
809         }
810 }
811
812 #ifdef CONFIG_NUMA
813 void __init
814 map_iosapic_to_node(unsigned int gsi_base, int node)
815 {
816         int index;
817
818         index = find_iosapic(gsi_base);
819         if (index < 0) {
820                 printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n",
821                        __FUNCTION__, gsi_base);
822                 return;
823         }
824         iosapic_lists[index].node = node;
825         return;
826 }
827 #endif