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1/*
2 * pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $)
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 *
24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 *
26 * TBD:
27 * 1. Support more than one IRQ resource entry per link device (index).
28 * 2. Implement start/stop mechanism and use ACPI Bus Driver facilities
29 * for IRQ management (e.g. start()->_SRS).
30 */
31
32#include <linux/syscore_ops.h>
33#include <linux/kernel.h>
34#include <linux/module.h>
35#include <linux/init.h>
36#include <linux/types.h>
37#include <linux/spinlock.h>
38#include <linux/pm.h>
39#include <linux/pci.h>
40#include <linux/mutex.h>
41#include <linux/slab.h>
42
43#include <acpi/acpi_bus.h>
44#include <acpi/acpi_drivers.h>
45
46#define PREFIX "ACPI: "
47
48#define _COMPONENT ACPI_PCI_COMPONENT
49ACPI_MODULE_NAME("pci_link");
50#define ACPI_PCI_LINK_CLASS "pci_irq_routing"
51#define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link"
52#define ACPI_PCI_LINK_FILE_INFO "info"
53#define ACPI_PCI_LINK_FILE_STATUS "state"
54#define ACPI_PCI_LINK_MAX_POSSIBLE 16
55
56static int acpi_pci_link_add(struct acpi_device *device);
57static int acpi_pci_link_remove(struct acpi_device *device, int type);
58
59static const struct acpi_device_id link_device_ids[] = {
60 {"PNP0C0F", 0},
61 {"", 0},
62};
63MODULE_DEVICE_TABLE(acpi, link_device_ids);
64
65static struct acpi_driver acpi_pci_link_driver = {
66 .name = "pci_link",
67 .class = ACPI_PCI_LINK_CLASS,
68 .ids = link_device_ids,
69 .ops = {
70 .add = acpi_pci_link_add,
71 .remove = acpi_pci_link_remove,
72 },
73};
74
75/*
76 * If a link is initialized, we never change its active and initialized
77 * later even the link is disable. Instead, we just repick the active irq
78 */
79struct acpi_pci_link_irq {
80 u8 active; /* Current IRQ */
81 u8 triggering; /* All IRQs */
82 u8 polarity; /* All IRQs */
83 u8 resource_type;
84 u8 possible_count;
85 u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
86 u8 initialized:1;
87 u8 reserved:7;
88};
89
90struct acpi_pci_link {
91 struct list_head list;
92 struct acpi_device *device;
93 struct acpi_pci_link_irq irq;
94 int refcnt;
95};
96
97static LIST_HEAD(acpi_link_list);
98static DEFINE_MUTEX(acpi_link_lock);
99
100/* --------------------------------------------------------------------------
101 PCI Link Device Management
102 -------------------------------------------------------------------------- */
103
104/*
105 * set context (link) possible list from resource list
106 */
107static acpi_status acpi_pci_link_check_possible(struct acpi_resource *resource,
108 void *context)
109{
110 struct acpi_pci_link *link = context;
111 u32 i;
112
113 switch (resource->type) {
114 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
115 case ACPI_RESOURCE_TYPE_END_TAG:
116 return AE_OK;
117 case ACPI_RESOURCE_TYPE_IRQ:
118 {
119 struct acpi_resource_irq *p = &resource->data.irq;
120 if (!p || !p->interrupt_count) {
121 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
122 "Blank _PRS IRQ resource\n"));
123 return AE_OK;
124 }
125 for (i = 0;
126 (i < p->interrupt_count
127 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
128 if (!p->interrupts[i]) {
129 printk(KERN_WARNING PREFIX
130 "Invalid _PRS IRQ %d\n",
131 p->interrupts[i]);
132 continue;
133 }
134 link->irq.possible[i] = p->interrupts[i];
135 link->irq.possible_count++;
136 }
137 link->irq.triggering = p->triggering;
138 link->irq.polarity = p->polarity;
139 link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
140 break;
141 }
142 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
143 {
144 struct acpi_resource_extended_irq *p =
145 &resource->data.extended_irq;
146 if (!p || !p->interrupt_count) {
147 printk(KERN_WARNING PREFIX
148 "Blank _PRS EXT IRQ resource\n");
149 return AE_OK;
150 }
151 for (i = 0;
152 (i < p->interrupt_count
153 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
154 if (!p->interrupts[i]) {
155 printk(KERN_WARNING PREFIX
156 "Invalid _PRS IRQ %d\n",
157 p->interrupts[i]);
158 continue;
159 }
160 link->irq.possible[i] = p->interrupts[i];
161 link->irq.possible_count++;
162 }
163 link->irq.triggering = p->triggering;
164 link->irq.polarity = p->polarity;
165 link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
166 break;
167 }
168 default:
169 printk(KERN_ERR PREFIX "_PRS resource type 0x%x isn't an IRQ\n",
170 resource->type);
171 return AE_OK;
172 }
173
174 return AE_CTRL_TERMINATE;
175}
176
177static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
178{
179 acpi_status status;
180
181 status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
182 acpi_pci_link_check_possible, link);
183 if (ACPI_FAILURE(status)) {
184 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
185 return -ENODEV;
186 }
187
188 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
189 "Found %d possible IRQs\n",
190 link->irq.possible_count));
191
192 return 0;
193}
194
195static acpi_status acpi_pci_link_check_current(struct acpi_resource *resource,
196 void *context)
197{
198 int *irq = context;
199
200 switch (resource->type) {
201 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
202 case ACPI_RESOURCE_TYPE_END_TAG:
203 return AE_OK;
204 case ACPI_RESOURCE_TYPE_IRQ:
205 {
206 struct acpi_resource_irq *p = &resource->data.irq;
207 if (!p || !p->interrupt_count) {
208 /*
209 * IRQ descriptors may have no IRQ# bits set,
210 * particularly those those w/ _STA disabled
211 */
212 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
213 "Blank _CRS IRQ resource\n"));
214 return AE_OK;
215 }
216 *irq = p->interrupts[0];
217 break;
218 }
219 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
220 {
221 struct acpi_resource_extended_irq *p =
222 &resource->data.extended_irq;
223 if (!p || !p->interrupt_count) {
224 /*
225 * extended IRQ descriptors must
226 * return at least 1 IRQ
227 */
228 printk(KERN_WARNING PREFIX
229 "Blank _CRS EXT IRQ resource\n");
230 return AE_OK;
231 }
232 *irq = p->interrupts[0];
233 break;
234 }
235 break;
236 default:
237 printk(KERN_ERR PREFIX "_CRS resource type 0x%x isn't an IRQ\n",
238 resource->type);
239 return AE_OK;
240 }
241
242 return AE_CTRL_TERMINATE;
243}
244
245/*
246 * Run _CRS and set link->irq.active
247 *
248 * return value:
249 * 0 - success
250 * !0 - failure
251 */
252static int acpi_pci_link_get_current(struct acpi_pci_link *link)
253{
254 int result = 0;
255 acpi_status status;
256 int irq = 0;
257
258 link->irq.active = 0;
259
260 /* in practice, status disabled is meaningless, ignore it */
261 if (acpi_strict) {
262 /* Query _STA, set link->device->status */
263 result = acpi_bus_get_status(link->device);
264 if (result) {
265 printk(KERN_ERR PREFIX "Unable to read status\n");
266 goto end;
267 }
268
269 if (!link->device->status.enabled) {
270 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
271 return 0;
272 }
273 }
274
275 /*
276 * Query and parse _CRS to get the current IRQ assignment.
277 */
278
279 status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
280 acpi_pci_link_check_current, &irq);
281 if (ACPI_FAILURE(status)) {
282 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
283 result = -ENODEV;
284 goto end;
285 }
286
287 if (acpi_strict && !irq) {
288 printk(KERN_ERR PREFIX "_CRS returned 0\n");
289 result = -ENODEV;
290 }
291
292 link->irq.active = irq;
293
294 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
295
296 end:
297 return result;
298}
299
300static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
301{
302 int result;
303 acpi_status status;
304 struct {
305 struct acpi_resource res;
306 struct acpi_resource end;
307 } *resource;
308 struct acpi_buffer buffer = { 0, NULL };
309
310 if (!irq)
311 return -EINVAL;
312
313 resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
314 if (!resource)
315 return -ENOMEM;
316
317 buffer.length = sizeof(*resource) + 1;
318 buffer.pointer = resource;
319
320 switch (link->irq.resource_type) {
321 case ACPI_RESOURCE_TYPE_IRQ:
322 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
323 resource->res.length = sizeof(struct acpi_resource);
324 resource->res.data.irq.triggering = link->irq.triggering;
325 resource->res.data.irq.polarity =
326 link->irq.polarity;
327 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
328 resource->res.data.irq.sharable =
329 ACPI_EXCLUSIVE;
330 else
331 resource->res.data.irq.sharable = ACPI_SHARED;
332 resource->res.data.irq.interrupt_count = 1;
333 resource->res.data.irq.interrupts[0] = irq;
334 break;
335
336 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
337 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
338 resource->res.length = sizeof(struct acpi_resource);
339 resource->res.data.extended_irq.producer_consumer =
340 ACPI_CONSUMER;
341 resource->res.data.extended_irq.triggering =
342 link->irq.triggering;
343 resource->res.data.extended_irq.polarity =
344 link->irq.polarity;
345 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
346 resource->res.data.irq.sharable =
347 ACPI_EXCLUSIVE;
348 else
349 resource->res.data.irq.sharable = ACPI_SHARED;
350 resource->res.data.extended_irq.interrupt_count = 1;
351 resource->res.data.extended_irq.interrupts[0] = irq;
352 /* ignore resource_source, it's optional */
353 break;
354 default:
355 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
356 result = -EINVAL;
357 goto end;
358
359 }
360 resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
361
362 /* Attempt to set the resource */
363 status = acpi_set_current_resources(link->device->handle, &buffer);
364
365 /* check for total failure */
366 if (ACPI_FAILURE(status)) {
367 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
368 result = -ENODEV;
369 goto end;
370 }
371
372 /* Query _STA, set device->status */
373 result = acpi_bus_get_status(link->device);
374 if (result) {
375 printk(KERN_ERR PREFIX "Unable to read status\n");
376 goto end;
377 }
378 if (!link->device->status.enabled) {
379 printk(KERN_WARNING PREFIX
380 "%s [%s] disabled and referenced, BIOS bug\n",
381 acpi_device_name(link->device),
382 acpi_device_bid(link->device));
383 }
384
385 /* Query _CRS, set link->irq.active */
386 result = acpi_pci_link_get_current(link);
387 if (result) {
388 goto end;
389 }
390
391 /*
392 * Is current setting not what we set?
393 * set link->irq.active
394 */
395 if (link->irq.active != irq) {
396 /*
397 * policy: when _CRS doesn't return what we just _SRS
398 * assume _SRS worked and override _CRS value.
399 */
400 printk(KERN_WARNING PREFIX
401 "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
402 acpi_device_name(link->device),
403 acpi_device_bid(link->device), link->irq.active, irq);
404 link->irq.active = irq;
405 }
406
407 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
408
409 end:
410 kfree(resource);
411 return result;
412}
413
414/* --------------------------------------------------------------------------
415 PCI Link IRQ Management
416 -------------------------------------------------------------------------- */
417
418/*
419 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
420 * Link Devices to move the PIRQs around to minimize sharing.
421 *
422 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
423 * that the BIOS has already set to active. This is necessary because
424 * ACPI has no automatic means of knowing what ISA IRQs are used. Note that
425 * if the BIOS doesn't set a Link Device active, ACPI needs to program it
426 * even if acpi_irq_nobalance is set.
427 *
428 * A tables of penalties avoids directing PCI interrupts to well known
429 * ISA IRQs. Boot params are available to over-ride the default table:
430 *
431 * List interrupts that are free for PCI use.
432 * acpi_irq_pci=n[,m]
433 *
434 * List interrupts that should not be used for PCI:
435 * acpi_irq_isa=n[,m]
436 *
437 * Note that PCI IRQ routers have a list of possible IRQs,
438 * which may not include the IRQs this table says are available.
439 *
440 * Since this heuristic can't tell the difference between a link
441 * that no device will attach to, vs. a link which may be shared
442 * by multiple active devices -- it is not optimal.
443 *
444 * If interrupt performance is that important, get an IO-APIC system
445 * with a pin dedicated to each device. Or for that matter, an MSI
446 * enabled system.
447 */
448
449#define ACPI_MAX_IRQS 256
450#define ACPI_MAX_ISA_IRQ 16
451
452#define PIRQ_PENALTY_PCI_AVAILABLE (0)
453#define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
454#define PIRQ_PENALTY_PCI_USING (16*16*16)
455#define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16)
456#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
457#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)
458
459static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
460 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
461 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
462 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
463 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */
464 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */
465 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */
466 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */
467 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */
468 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */
469 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */
470 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */
471 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */
472 PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */
473 PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
474 PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
475 PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
476 /* >IRQ15 */
477};
478
479int __init acpi_irq_penalty_init(void)
480{
481 struct acpi_pci_link *link;
482 int i;
483
484 /*
485 * Update penalties to facilitate IRQ balancing.
486 */
487 list_for_each_entry(link, &acpi_link_list, list) {
488
489 /*
490 * reflect the possible and active irqs in the penalty table --
491 * useful for breaking ties.
492 */
493 if (link->irq.possible_count) {
494 int penalty =
495 PIRQ_PENALTY_PCI_POSSIBLE /
496 link->irq.possible_count;
497
498 for (i = 0; i < link->irq.possible_count; i++) {
499 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
500 acpi_irq_penalty[link->irq.
501 possible[i]] +=
502 penalty;
503 }
504
505 } else if (link->irq.active) {
506 acpi_irq_penalty[link->irq.active] +=
507 PIRQ_PENALTY_PCI_POSSIBLE;
508 }
509 }
510 /* Add a penalty for the SCI */
511 acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;
512 return 0;
513}
514
515static int acpi_irq_balance = -1; /* 0: static, 1: balance */
516
517static int acpi_pci_link_allocate(struct acpi_pci_link *link)
518{
519 int irq;
520 int i;
521
522 if (link->irq.initialized) {
523 if (link->refcnt == 0)
524 /* This means the link is disabled but initialized */
525 acpi_pci_link_set(link, link->irq.active);
526 return 0;
527 }
528
529 /*
530 * search for active IRQ in list of possible IRQs.
531 */
532 for (i = 0; i < link->irq.possible_count; ++i) {
533 if (link->irq.active == link->irq.possible[i])
534 break;
535 }
536 /*
537 * forget active IRQ that is not in possible list
538 */
539 if (i == link->irq.possible_count) {
540 if (acpi_strict)
541 printk(KERN_WARNING PREFIX "_CRS %d not found"
542 " in _PRS\n", link->irq.active);
543 link->irq.active = 0;
544 }
545
546 /*
547 * if active found, use it; else pick entry from end of possible list.
548 */
549 if (link->irq.active)
550 irq = link->irq.active;
551 else
552 irq = link->irq.possible[link->irq.possible_count - 1];
553
554 if (acpi_irq_balance || !link->irq.active) {
555 /*
556 * Select the best IRQ. This is done in reverse to promote
557 * the use of IRQs 9, 10, 11, and >15.
558 */
559 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
560 if (acpi_irq_penalty[irq] >
561 acpi_irq_penalty[link->irq.possible[i]])
562 irq = link->irq.possible[i];
563 }
564 }
565
566 /* Attempt to enable the link device at this IRQ. */
567 if (acpi_pci_link_set(link, irq)) {
568 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
569 "Try pci=noacpi or acpi=off\n",
570 acpi_device_name(link->device),
571 acpi_device_bid(link->device));
572 return -ENODEV;
573 } else {
574 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
575 printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
576 acpi_device_name(link->device),
577 acpi_device_bid(link->device), link->irq.active);
578 }
579
580 link->irq.initialized = 1;
581 return 0;
582}
583
584/*
585 * acpi_pci_link_allocate_irq
586 * success: return IRQ >= 0
587 * failure: return -1
588 */
589int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering,
590 int *polarity, char **name)
591{
592 int result;
593 struct acpi_device *device;
594 struct acpi_pci_link *link;
595
596 result = acpi_bus_get_device(handle, &device);
597 if (result) {
598 printk(KERN_ERR PREFIX "Invalid link device\n");
599 return -1;
600 }
601
602 link = acpi_driver_data(device);
603 if (!link) {
604 printk(KERN_ERR PREFIX "Invalid link context\n");
605 return -1;
606 }
607
608 /* TBD: Support multiple index (IRQ) entries per Link Device */
609 if (index) {
610 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
611 return -1;
612 }
613
614 mutex_lock(&acpi_link_lock);
615 if (acpi_pci_link_allocate(link)) {
616 mutex_unlock(&acpi_link_lock);
617 return -1;
618 }
619
620 if (!link->irq.active) {
621 mutex_unlock(&acpi_link_lock);
622 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
623 return -1;
624 }
625 link->refcnt++;
626 mutex_unlock(&acpi_link_lock);
627
628 if (triggering)
629 *triggering = link->irq.triggering;
630 if (polarity)
631 *polarity = link->irq.polarity;
632 if (name)
633 *name = acpi_device_bid(link->device);
634 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
635 "Link %s is referenced\n",
636 acpi_device_bid(link->device)));
637 return (link->irq.active);
638}
639
640/*
641 * We don't change link's irq information here. After it is reenabled, we
642 * continue use the info
643 */
644int acpi_pci_link_free_irq(acpi_handle handle)
645{
646 struct acpi_device *device;
647 struct acpi_pci_link *link;
648 acpi_status result;
649
650 result = acpi_bus_get_device(handle, &device);
651 if (result) {
652 printk(KERN_ERR PREFIX "Invalid link device\n");
653 return -1;
654 }
655
656 link = acpi_driver_data(device);
657 if (!link) {
658 printk(KERN_ERR PREFIX "Invalid link context\n");
659 return -1;
660 }
661
662 mutex_lock(&acpi_link_lock);
663 if (!link->irq.initialized) {
664 mutex_unlock(&acpi_link_lock);
665 printk(KERN_ERR PREFIX "Link isn't initialized\n");
666 return -1;
667 }
668#ifdef FUTURE_USE
669 /*
670 * The Link reference count allows us to _DISable an unused link
671 * and suspend time, and set it again on resume.
672 * However, 2.6.12 still has irq_router.resume
673 * which blindly restores the link state.
674 * So we disable the reference count method
675 * to prevent duplicate acpi_pci_link_set()
676 * which would harm some systems
677 */
678 link->refcnt--;
679#endif
680 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
681 "Link %s is dereferenced\n",
682 acpi_device_bid(link->device)));
683
684 if (link->refcnt == 0)
685 acpi_evaluate_object(link->device->handle, "_DIS", NULL, NULL);
686
687 mutex_unlock(&acpi_link_lock);
688 return (link->irq.active);
689}
690
691/* --------------------------------------------------------------------------
692 Driver Interface
693 -------------------------------------------------------------------------- */
694
695static int acpi_pci_link_add(struct acpi_device *device)
696{
697 int result;
698 struct acpi_pci_link *link;
699 int i;
700 int found = 0;
701
702 link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
703 if (!link)
704 return -ENOMEM;
705
706 link->device = device;
707 strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
708 strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
709 device->driver_data = link;
710
711 mutex_lock(&acpi_link_lock);
712 result = acpi_pci_link_get_possible(link);
713 if (result)
714 goto end;
715
716 /* query and set link->irq.active */
717 acpi_pci_link_get_current(link);
718
719 printk(KERN_INFO PREFIX "%s [%s] (IRQs", acpi_device_name(device),
720 acpi_device_bid(device));
721 for (i = 0; i < link->irq.possible_count; i++) {
722 if (link->irq.active == link->irq.possible[i]) {
723 printk(" *%d", link->irq.possible[i]);
724 found = 1;
725 } else
726 printk(" %d", link->irq.possible[i]);
727 }
728
729 printk(")");
730
731 if (!found)
732 printk(" *%d", link->irq.active);
733
734 if (!link->device->status.enabled)
735 printk(", disabled.");
736
737 printk("\n");
738
739 list_add_tail(&link->list, &acpi_link_list);
740
741 end:
742 /* disable all links -- to be activated on use */
743 acpi_evaluate_object(device->handle, "_DIS", NULL, NULL);
744 mutex_unlock(&acpi_link_lock);
745
746 if (result)
747 kfree(link);
748
749 return result;
750}
751
752static int acpi_pci_link_resume(struct acpi_pci_link *link)
753{
754 if (link->refcnt && link->irq.active && link->irq.initialized)
755 return (acpi_pci_link_set(link, link->irq.active));
756
757 return 0;
758}
759
760static void irqrouter_resume(void)
761{
762 struct acpi_pci_link *link;
763
764 list_for_each_entry(link, &acpi_link_list, list) {
765 acpi_pci_link_resume(link);
766 }
767}
768
769static int acpi_pci_link_remove(struct acpi_device *device, int type)
770{
771 struct acpi_pci_link *link;
772
773 link = acpi_driver_data(device);
774
775 mutex_lock(&acpi_link_lock);
776 list_del(&link->list);
777 mutex_unlock(&acpi_link_lock);
778
779 kfree(link);
780 return 0;
781}
782
783/*
784 * modify acpi_irq_penalty[] from cmdline
785 */
786static int __init acpi_irq_penalty_update(char *str, int used)
787{
788 int i;
789
790 for (i = 0; i < 16; i++) {
791 int retval;
792 int irq;
793
794 retval = get_option(&str, &irq);
795
796 if (!retval)
797 break; /* no number found */
798
799 if (irq < 0)
800 continue;
801
802 if (irq >= ARRAY_SIZE(acpi_irq_penalty))
803 continue;
804
805 if (used)
806 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
807 else
808 acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
809
810 if (retval != 2) /* no next number */
811 break;
812 }
813 return 1;
814}
815
816/*
817 * We'd like PNP to call this routine for the
818 * single ISA_USED value for each legacy device.
819 * But instead it calls us with each POSSIBLE setting.
820 * There is no ISA_POSSIBLE weight, so we simply use
821 * the (small) PCI_USING penalty.
822 */
823void acpi_penalize_isa_irq(int irq, int active)
824{
825 if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
826 if (active)
827 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
828 else
829 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
830 }
831}
832
833/*
834 * Over-ride default table to reserve additional IRQs for use by ISA
835 * e.g. acpi_irq_isa=5
836 * Useful for telling ACPI how not to interfere with your ISA sound card.
837 */
838static int __init acpi_irq_isa(char *str)
839{
840 return acpi_irq_penalty_update(str, 1);
841}
842
843__setup("acpi_irq_isa=", acpi_irq_isa);
844
845/*
846 * Over-ride default table to free additional IRQs for use by PCI
847 * e.g. acpi_irq_pci=7,15
848 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
849 */
850static int __init acpi_irq_pci(char *str)
851{
852 return acpi_irq_penalty_update(str, 0);
853}
854
855__setup("acpi_irq_pci=", acpi_irq_pci);
856
857static int __init acpi_irq_nobalance_set(char *str)
858{
859 acpi_irq_balance = 0;
860 return 1;
861}
862
863__setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
864
865static int __init acpi_irq_balance_set(char *str)
866{
867 acpi_irq_balance = 1;
868 return 1;
869}
870
871__setup("acpi_irq_balance", acpi_irq_balance_set);
872
873static struct syscore_ops irqrouter_syscore_ops = {
874 .resume = irqrouter_resume,
875};
876
877static int __init irqrouter_init_ops(void)
878{
879 if (!acpi_disabled && !acpi_noirq)
880 register_syscore_ops(&irqrouter_syscore_ops);
881
882 return 0;
883}
884
885device_initcall(irqrouter_init_ops);
886
887static int __init acpi_pci_link_init(void)
888{
889 if (acpi_noirq)
890 return 0;
891
892 if (acpi_irq_balance == -1) {
893 /* no command line switch: enable balancing in IOAPIC mode */
894 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC)
895 acpi_irq_balance = 1;
896 else
897 acpi_irq_balance = 0;
898 }
899
900 if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
901 return -ENODEV;
902
903 return 0;
904}
905
906subsys_initcall(acpi_pci_link_init);
1/*
2 * pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $)
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 *
24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 *
26 * TBD:
27 * 1. Support more than one IRQ resource entry per link device (index).
28 * 2. Implement start/stop mechanism and use ACPI Bus Driver facilities
29 * for IRQ management (e.g. start()->_SRS).
30 */
31
32#include <linux/syscore_ops.h>
33#include <linux/kernel.h>
34#include <linux/module.h>
35#include <linux/init.h>
36#include <linux/types.h>
37#include <linux/spinlock.h>
38#include <linux/pm.h>
39#include <linux/pci.h>
40#include <linux/mutex.h>
41#include <linux/slab.h>
42#include <linux/acpi.h>
43
44#include "internal.h"
45
46#define _COMPONENT ACPI_PCI_COMPONENT
47ACPI_MODULE_NAME("pci_link");
48#define ACPI_PCI_LINK_CLASS "pci_irq_routing"
49#define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link"
50#define ACPI_PCI_LINK_FILE_INFO "info"
51#define ACPI_PCI_LINK_FILE_STATUS "state"
52#define ACPI_PCI_LINK_MAX_POSSIBLE 16
53
54static int acpi_pci_link_add(struct acpi_device *device,
55 const struct acpi_device_id *not_used);
56static void acpi_pci_link_remove(struct acpi_device *device);
57
58static const struct acpi_device_id link_device_ids[] = {
59 {"PNP0C0F", 0},
60 {"", 0},
61};
62
63static struct acpi_scan_handler pci_link_handler = {
64 .ids = link_device_ids,
65 .attach = acpi_pci_link_add,
66 .detach = acpi_pci_link_remove,
67};
68
69/*
70 * If a link is initialized, we never change its active and initialized
71 * later even the link is disable. Instead, we just repick the active irq
72 */
73struct acpi_pci_link_irq {
74 u8 active; /* Current IRQ */
75 u8 triggering; /* All IRQs */
76 u8 polarity; /* All IRQs */
77 u8 resource_type;
78 u8 possible_count;
79 u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
80 u8 initialized:1;
81 u8 reserved:7;
82};
83
84struct acpi_pci_link {
85 struct list_head list;
86 struct acpi_device *device;
87 struct acpi_pci_link_irq irq;
88 int refcnt;
89};
90
91static LIST_HEAD(acpi_link_list);
92static DEFINE_MUTEX(acpi_link_lock);
93
94/* --------------------------------------------------------------------------
95 PCI Link Device Management
96 -------------------------------------------------------------------------- */
97
98/*
99 * set context (link) possible list from resource list
100 */
101static acpi_status acpi_pci_link_check_possible(struct acpi_resource *resource,
102 void *context)
103{
104 struct acpi_pci_link *link = context;
105 u32 i;
106
107 switch (resource->type) {
108 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
109 case ACPI_RESOURCE_TYPE_END_TAG:
110 return AE_OK;
111 case ACPI_RESOURCE_TYPE_IRQ:
112 {
113 struct acpi_resource_irq *p = &resource->data.irq;
114 if (!p || !p->interrupt_count) {
115 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
116 "Blank _PRS IRQ resource\n"));
117 return AE_OK;
118 }
119 for (i = 0;
120 (i < p->interrupt_count
121 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
122 if (!p->interrupts[i]) {
123 printk(KERN_WARNING PREFIX
124 "Invalid _PRS IRQ %d\n",
125 p->interrupts[i]);
126 continue;
127 }
128 link->irq.possible[i] = p->interrupts[i];
129 link->irq.possible_count++;
130 }
131 link->irq.triggering = p->triggering;
132 link->irq.polarity = p->polarity;
133 link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
134 break;
135 }
136 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
137 {
138 struct acpi_resource_extended_irq *p =
139 &resource->data.extended_irq;
140 if (!p || !p->interrupt_count) {
141 printk(KERN_WARNING PREFIX
142 "Blank _PRS EXT IRQ resource\n");
143 return AE_OK;
144 }
145 for (i = 0;
146 (i < p->interrupt_count
147 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
148 if (!p->interrupts[i]) {
149 printk(KERN_WARNING PREFIX
150 "Invalid _PRS IRQ %d\n",
151 p->interrupts[i]);
152 continue;
153 }
154 link->irq.possible[i] = p->interrupts[i];
155 link->irq.possible_count++;
156 }
157 link->irq.triggering = p->triggering;
158 link->irq.polarity = p->polarity;
159 link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
160 break;
161 }
162 default:
163 printk(KERN_ERR PREFIX "_PRS resource type 0x%x isn't an IRQ\n",
164 resource->type);
165 return AE_OK;
166 }
167
168 return AE_CTRL_TERMINATE;
169}
170
171static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
172{
173 acpi_status status;
174
175 status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
176 acpi_pci_link_check_possible, link);
177 if (ACPI_FAILURE(status)) {
178 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
179 return -ENODEV;
180 }
181
182 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
183 "Found %d possible IRQs\n",
184 link->irq.possible_count));
185
186 return 0;
187}
188
189static acpi_status acpi_pci_link_check_current(struct acpi_resource *resource,
190 void *context)
191{
192 int *irq = context;
193
194 switch (resource->type) {
195 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
196 case ACPI_RESOURCE_TYPE_END_TAG:
197 return AE_OK;
198 case ACPI_RESOURCE_TYPE_IRQ:
199 {
200 struct acpi_resource_irq *p = &resource->data.irq;
201 if (!p || !p->interrupt_count) {
202 /*
203 * IRQ descriptors may have no IRQ# bits set,
204 * particularly those those w/ _STA disabled
205 */
206 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
207 "Blank _CRS IRQ resource\n"));
208 return AE_OK;
209 }
210 *irq = p->interrupts[0];
211 break;
212 }
213 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
214 {
215 struct acpi_resource_extended_irq *p =
216 &resource->data.extended_irq;
217 if (!p || !p->interrupt_count) {
218 /*
219 * extended IRQ descriptors must
220 * return at least 1 IRQ
221 */
222 printk(KERN_WARNING PREFIX
223 "Blank _CRS EXT IRQ resource\n");
224 return AE_OK;
225 }
226 *irq = p->interrupts[0];
227 break;
228 }
229 break;
230 default:
231 printk(KERN_ERR PREFIX "_CRS resource type 0x%x isn't an IRQ\n",
232 resource->type);
233 return AE_OK;
234 }
235
236 return AE_CTRL_TERMINATE;
237}
238
239/*
240 * Run _CRS and set link->irq.active
241 *
242 * return value:
243 * 0 - success
244 * !0 - failure
245 */
246static int acpi_pci_link_get_current(struct acpi_pci_link *link)
247{
248 int result = 0;
249 acpi_status status;
250 int irq = 0;
251
252 link->irq.active = 0;
253
254 /* in practice, status disabled is meaningless, ignore it */
255 if (acpi_strict) {
256 /* Query _STA, set link->device->status */
257 result = acpi_bus_get_status(link->device);
258 if (result) {
259 printk(KERN_ERR PREFIX "Unable to read status\n");
260 goto end;
261 }
262
263 if (!link->device->status.enabled) {
264 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
265 return 0;
266 }
267 }
268
269 /*
270 * Query and parse _CRS to get the current IRQ assignment.
271 */
272
273 status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
274 acpi_pci_link_check_current, &irq);
275 if (ACPI_FAILURE(status)) {
276 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
277 result = -ENODEV;
278 goto end;
279 }
280
281 if (acpi_strict && !irq) {
282 printk(KERN_ERR PREFIX "_CRS returned 0\n");
283 result = -ENODEV;
284 }
285
286 link->irq.active = irq;
287
288 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
289
290 end:
291 return result;
292}
293
294static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
295{
296 int result;
297 acpi_status status;
298 struct {
299 struct acpi_resource res;
300 struct acpi_resource end;
301 } *resource;
302 struct acpi_buffer buffer = { 0, NULL };
303
304 if (!irq)
305 return -EINVAL;
306
307 resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
308 if (!resource)
309 return -ENOMEM;
310
311 buffer.length = sizeof(*resource) + 1;
312 buffer.pointer = resource;
313
314 switch (link->irq.resource_type) {
315 case ACPI_RESOURCE_TYPE_IRQ:
316 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
317 resource->res.length = sizeof(struct acpi_resource);
318 resource->res.data.irq.triggering = link->irq.triggering;
319 resource->res.data.irq.polarity =
320 link->irq.polarity;
321 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
322 resource->res.data.irq.sharable =
323 ACPI_EXCLUSIVE;
324 else
325 resource->res.data.irq.sharable = ACPI_SHARED;
326 resource->res.data.irq.interrupt_count = 1;
327 resource->res.data.irq.interrupts[0] = irq;
328 break;
329
330 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
331 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
332 resource->res.length = sizeof(struct acpi_resource);
333 resource->res.data.extended_irq.producer_consumer =
334 ACPI_CONSUMER;
335 resource->res.data.extended_irq.triggering =
336 link->irq.triggering;
337 resource->res.data.extended_irq.polarity =
338 link->irq.polarity;
339 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
340 resource->res.data.irq.sharable =
341 ACPI_EXCLUSIVE;
342 else
343 resource->res.data.irq.sharable = ACPI_SHARED;
344 resource->res.data.extended_irq.interrupt_count = 1;
345 resource->res.data.extended_irq.interrupts[0] = irq;
346 /* ignore resource_source, it's optional */
347 break;
348 default:
349 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
350 result = -EINVAL;
351 goto end;
352
353 }
354 resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
355 resource->end.length = sizeof(struct acpi_resource);
356
357 /* Attempt to set the resource */
358 status = acpi_set_current_resources(link->device->handle, &buffer);
359
360 /* check for total failure */
361 if (ACPI_FAILURE(status)) {
362 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
363 result = -ENODEV;
364 goto end;
365 }
366
367 /* Query _STA, set device->status */
368 result = acpi_bus_get_status(link->device);
369 if (result) {
370 printk(KERN_ERR PREFIX "Unable to read status\n");
371 goto end;
372 }
373 if (!link->device->status.enabled) {
374 printk(KERN_WARNING PREFIX
375 "%s [%s] disabled and referenced, BIOS bug\n",
376 acpi_device_name(link->device),
377 acpi_device_bid(link->device));
378 }
379
380 /* Query _CRS, set link->irq.active */
381 result = acpi_pci_link_get_current(link);
382 if (result) {
383 goto end;
384 }
385
386 /*
387 * Is current setting not what we set?
388 * set link->irq.active
389 */
390 if (link->irq.active != irq) {
391 /*
392 * policy: when _CRS doesn't return what we just _SRS
393 * assume _SRS worked and override _CRS value.
394 */
395 printk(KERN_WARNING PREFIX
396 "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
397 acpi_device_name(link->device),
398 acpi_device_bid(link->device), link->irq.active, irq);
399 link->irq.active = irq;
400 }
401
402 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
403
404 end:
405 kfree(resource);
406 return result;
407}
408
409/* --------------------------------------------------------------------------
410 PCI Link IRQ Management
411 -------------------------------------------------------------------------- */
412
413/*
414 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
415 * Link Devices to move the PIRQs around to minimize sharing.
416 *
417 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
418 * that the BIOS has already set to active. This is necessary because
419 * ACPI has no automatic means of knowing what ISA IRQs are used. Note that
420 * if the BIOS doesn't set a Link Device active, ACPI needs to program it
421 * even if acpi_irq_nobalance is set.
422 *
423 * A tables of penalties avoids directing PCI interrupts to well known
424 * ISA IRQs. Boot params are available to over-ride the default table:
425 *
426 * List interrupts that are free for PCI use.
427 * acpi_irq_pci=n[,m]
428 *
429 * List interrupts that should not be used for PCI:
430 * acpi_irq_isa=n[,m]
431 *
432 * Note that PCI IRQ routers have a list of possible IRQs,
433 * which may not include the IRQs this table says are available.
434 *
435 * Since this heuristic can't tell the difference between a link
436 * that no device will attach to, vs. a link which may be shared
437 * by multiple active devices -- it is not optimal.
438 *
439 * If interrupt performance is that important, get an IO-APIC system
440 * with a pin dedicated to each device. Or for that matter, an MSI
441 * enabled system.
442 */
443
444#define ACPI_MAX_IRQS 256
445#define ACPI_MAX_ISA_IRQ 16
446
447#define PIRQ_PENALTY_PCI_AVAILABLE (0)
448#define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
449#define PIRQ_PENALTY_PCI_USING (16*16*16)
450#define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16)
451#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
452#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)
453
454static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
455 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
456 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
457 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
458 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */
459 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */
460 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */
461 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */
462 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */
463 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */
464 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */
465 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */
466 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */
467 PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */
468 PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
469 PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
470 PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
471 /* >IRQ15 */
472};
473
474int __init acpi_irq_penalty_init(void)
475{
476 struct acpi_pci_link *link;
477 int i;
478
479 /*
480 * Update penalties to facilitate IRQ balancing.
481 */
482 list_for_each_entry(link, &acpi_link_list, list) {
483
484 /*
485 * reflect the possible and active irqs in the penalty table --
486 * useful for breaking ties.
487 */
488 if (link->irq.possible_count) {
489 int penalty =
490 PIRQ_PENALTY_PCI_POSSIBLE /
491 link->irq.possible_count;
492
493 for (i = 0; i < link->irq.possible_count; i++) {
494 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
495 acpi_irq_penalty[link->irq.
496 possible[i]] +=
497 penalty;
498 }
499
500 } else if (link->irq.active) {
501 acpi_irq_penalty[link->irq.active] +=
502 PIRQ_PENALTY_PCI_POSSIBLE;
503 }
504 }
505 /* Add a penalty for the SCI */
506 acpi_irq_penalty[acpi_gbl_FADT.sci_interrupt] += PIRQ_PENALTY_PCI_USING;
507 return 0;
508}
509
510static int acpi_irq_balance = -1; /* 0: static, 1: balance */
511
512static int acpi_pci_link_allocate(struct acpi_pci_link *link)
513{
514 int irq;
515 int i;
516
517 if (link->irq.initialized) {
518 if (link->refcnt == 0)
519 /* This means the link is disabled but initialized */
520 acpi_pci_link_set(link, link->irq.active);
521 return 0;
522 }
523
524 /*
525 * search for active IRQ in list of possible IRQs.
526 */
527 for (i = 0; i < link->irq.possible_count; ++i) {
528 if (link->irq.active == link->irq.possible[i])
529 break;
530 }
531 /*
532 * forget active IRQ that is not in possible list
533 */
534 if (i == link->irq.possible_count) {
535 if (acpi_strict)
536 printk(KERN_WARNING PREFIX "_CRS %d not found"
537 " in _PRS\n", link->irq.active);
538 link->irq.active = 0;
539 }
540
541 /*
542 * if active found, use it; else pick entry from end of possible list.
543 */
544 if (link->irq.active)
545 irq = link->irq.active;
546 else
547 irq = link->irq.possible[link->irq.possible_count - 1];
548
549 if (acpi_irq_balance || !link->irq.active) {
550 /*
551 * Select the best IRQ. This is done in reverse to promote
552 * the use of IRQs 9, 10, 11, and >15.
553 */
554 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
555 if (acpi_irq_penalty[irq] >
556 acpi_irq_penalty[link->irq.possible[i]])
557 irq = link->irq.possible[i];
558 }
559 }
560
561 /* Attempt to enable the link device at this IRQ. */
562 if (acpi_pci_link_set(link, irq)) {
563 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
564 "Try pci=noacpi or acpi=off\n",
565 acpi_device_name(link->device),
566 acpi_device_bid(link->device));
567 return -ENODEV;
568 } else {
569 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
570 printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
571 acpi_device_name(link->device),
572 acpi_device_bid(link->device), link->irq.active);
573 }
574
575 link->irq.initialized = 1;
576 return 0;
577}
578
579/*
580 * acpi_pci_link_allocate_irq
581 * success: return IRQ >= 0
582 * failure: return -1
583 */
584int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering,
585 int *polarity, char **name)
586{
587 int result;
588 struct acpi_device *device;
589 struct acpi_pci_link *link;
590
591 result = acpi_bus_get_device(handle, &device);
592 if (result) {
593 printk(KERN_ERR PREFIX "Invalid link device\n");
594 return -1;
595 }
596
597 link = acpi_driver_data(device);
598 if (!link) {
599 printk(KERN_ERR PREFIX "Invalid link context\n");
600 return -1;
601 }
602
603 /* TBD: Support multiple index (IRQ) entries per Link Device */
604 if (index) {
605 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
606 return -1;
607 }
608
609 mutex_lock(&acpi_link_lock);
610 if (acpi_pci_link_allocate(link)) {
611 mutex_unlock(&acpi_link_lock);
612 return -1;
613 }
614
615 if (!link->irq.active) {
616 mutex_unlock(&acpi_link_lock);
617 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
618 return -1;
619 }
620 link->refcnt++;
621 mutex_unlock(&acpi_link_lock);
622
623 if (triggering)
624 *triggering = link->irq.triggering;
625 if (polarity)
626 *polarity = link->irq.polarity;
627 if (name)
628 *name = acpi_device_bid(link->device);
629 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
630 "Link %s is referenced\n",
631 acpi_device_bid(link->device)));
632 return (link->irq.active);
633}
634
635/*
636 * We don't change link's irq information here. After it is reenabled, we
637 * continue use the info
638 */
639int acpi_pci_link_free_irq(acpi_handle handle)
640{
641 struct acpi_device *device;
642 struct acpi_pci_link *link;
643 acpi_status result;
644
645 result = acpi_bus_get_device(handle, &device);
646 if (result) {
647 printk(KERN_ERR PREFIX "Invalid link device\n");
648 return -1;
649 }
650
651 link = acpi_driver_data(device);
652 if (!link) {
653 printk(KERN_ERR PREFIX "Invalid link context\n");
654 return -1;
655 }
656
657 mutex_lock(&acpi_link_lock);
658 if (!link->irq.initialized) {
659 mutex_unlock(&acpi_link_lock);
660 printk(KERN_ERR PREFIX "Link isn't initialized\n");
661 return -1;
662 }
663#ifdef FUTURE_USE
664 /*
665 * The Link reference count allows us to _DISable an unused link
666 * and suspend time, and set it again on resume.
667 * However, 2.6.12 still has irq_router.resume
668 * which blindly restores the link state.
669 * So we disable the reference count method
670 * to prevent duplicate acpi_pci_link_set()
671 * which would harm some systems
672 */
673 link->refcnt--;
674#endif
675 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
676 "Link %s is dereferenced\n",
677 acpi_device_bid(link->device)));
678
679 if (link->refcnt == 0)
680 acpi_evaluate_object(link->device->handle, "_DIS", NULL, NULL);
681
682 mutex_unlock(&acpi_link_lock);
683 return (link->irq.active);
684}
685
686/* --------------------------------------------------------------------------
687 Driver Interface
688 -------------------------------------------------------------------------- */
689
690static int acpi_pci_link_add(struct acpi_device *device,
691 const struct acpi_device_id *not_used)
692{
693 int result;
694 struct acpi_pci_link *link;
695 int i;
696 int found = 0;
697
698 link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
699 if (!link)
700 return -ENOMEM;
701
702 link->device = device;
703 strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
704 strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
705 device->driver_data = link;
706
707 mutex_lock(&acpi_link_lock);
708 result = acpi_pci_link_get_possible(link);
709 if (result)
710 goto end;
711
712 /* query and set link->irq.active */
713 acpi_pci_link_get_current(link);
714
715 printk(KERN_INFO PREFIX "%s [%s] (IRQs", acpi_device_name(device),
716 acpi_device_bid(device));
717 for (i = 0; i < link->irq.possible_count; i++) {
718 if (link->irq.active == link->irq.possible[i]) {
719 printk(KERN_CONT " *%d", link->irq.possible[i]);
720 found = 1;
721 } else
722 printk(KERN_CONT " %d", link->irq.possible[i]);
723 }
724
725 printk(KERN_CONT ")");
726
727 if (!found)
728 printk(KERN_CONT " *%d", link->irq.active);
729
730 if (!link->device->status.enabled)
731 printk(KERN_CONT ", disabled.");
732
733 printk(KERN_CONT "\n");
734
735 list_add_tail(&link->list, &acpi_link_list);
736
737 end:
738 /* disable all links -- to be activated on use */
739 acpi_evaluate_object(device->handle, "_DIS", NULL, NULL);
740 mutex_unlock(&acpi_link_lock);
741
742 if (result)
743 kfree(link);
744
745 return result < 0 ? result : 1;
746}
747
748static int acpi_pci_link_resume(struct acpi_pci_link *link)
749{
750 if (link->refcnt && link->irq.active && link->irq.initialized)
751 return (acpi_pci_link_set(link, link->irq.active));
752
753 return 0;
754}
755
756static void irqrouter_resume(void)
757{
758 struct acpi_pci_link *link;
759
760 list_for_each_entry(link, &acpi_link_list, list) {
761 acpi_pci_link_resume(link);
762 }
763}
764
765static void acpi_pci_link_remove(struct acpi_device *device)
766{
767 struct acpi_pci_link *link;
768
769 link = acpi_driver_data(device);
770
771 mutex_lock(&acpi_link_lock);
772 list_del(&link->list);
773 mutex_unlock(&acpi_link_lock);
774
775 kfree(link);
776}
777
778/*
779 * modify acpi_irq_penalty[] from cmdline
780 */
781static int __init acpi_irq_penalty_update(char *str, int used)
782{
783 int i;
784
785 for (i = 0; i < 16; i++) {
786 int retval;
787 int irq;
788
789 retval = get_option(&str, &irq);
790
791 if (!retval)
792 break; /* no number found */
793
794 if (irq < 0)
795 continue;
796
797 if (irq >= ARRAY_SIZE(acpi_irq_penalty))
798 continue;
799
800 if (used)
801 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
802 else
803 acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
804
805 if (retval != 2) /* no next number */
806 break;
807 }
808 return 1;
809}
810
811/*
812 * We'd like PNP to call this routine for the
813 * single ISA_USED value for each legacy device.
814 * But instead it calls us with each POSSIBLE setting.
815 * There is no ISA_POSSIBLE weight, so we simply use
816 * the (small) PCI_USING penalty.
817 */
818void acpi_penalize_isa_irq(int irq, int active)
819{
820 if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
821 if (active)
822 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
823 else
824 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
825 }
826}
827
828/*
829 * Over-ride default table to reserve additional IRQs for use by ISA
830 * e.g. acpi_irq_isa=5
831 * Useful for telling ACPI how not to interfere with your ISA sound card.
832 */
833static int __init acpi_irq_isa(char *str)
834{
835 return acpi_irq_penalty_update(str, 1);
836}
837
838__setup("acpi_irq_isa=", acpi_irq_isa);
839
840/*
841 * Over-ride default table to free additional IRQs for use by PCI
842 * e.g. acpi_irq_pci=7,15
843 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
844 */
845static int __init acpi_irq_pci(char *str)
846{
847 return acpi_irq_penalty_update(str, 0);
848}
849
850__setup("acpi_irq_pci=", acpi_irq_pci);
851
852static int __init acpi_irq_nobalance_set(char *str)
853{
854 acpi_irq_balance = 0;
855 return 1;
856}
857
858__setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
859
860static int __init acpi_irq_balance_set(char *str)
861{
862 acpi_irq_balance = 1;
863 return 1;
864}
865
866__setup("acpi_irq_balance", acpi_irq_balance_set);
867
868static struct syscore_ops irqrouter_syscore_ops = {
869 .resume = irqrouter_resume,
870};
871
872void __init acpi_pci_link_init(void)
873{
874 if (acpi_noirq)
875 return;
876
877 if (acpi_irq_balance == -1) {
878 /* no command line switch: enable balancing in IOAPIC mode */
879 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC)
880 acpi_irq_balance = 1;
881 else
882 acpi_irq_balance = 0;
883 }
884 register_syscore_ops(&irqrouter_syscore_ops);
885 acpi_scan_add_handler(&pci_link_handler);
886}