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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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21 *
22 * TBD:
23 * 1. Support more than one IRQ resource entry per link device (index).
24 * 2. Implement start/stop mechanism and use ACPI Bus Driver facilities
25 * for IRQ management (e.g. start()->_SRS).
26 */
27
28#include <linux/syscore_ops.h>
29#include <linux/kernel.h>
30#include <linux/module.h>
31#include <linux/init.h>
32#include <linux/types.h>
33#include <linux/spinlock.h>
34#include <linux/pm.h>
35#include <linux/pci.h>
36#include <linux/mutex.h>
37#include <linux/slab.h>
38#include <linux/acpi.h>
39
40#include "internal.h"
41
42#define _COMPONENT ACPI_PCI_COMPONENT
43ACPI_MODULE_NAME("pci_link");
44#define ACPI_PCI_LINK_CLASS "pci_irq_routing"
45#define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link"
46#define ACPI_PCI_LINK_FILE_INFO "info"
47#define ACPI_PCI_LINK_FILE_STATUS "state"
48#define ACPI_PCI_LINK_MAX_POSSIBLE 16
49
50static int acpi_pci_link_add(struct acpi_device *device,
51 const struct acpi_device_id *not_used);
52static void acpi_pci_link_remove(struct acpi_device *device);
53
54static const struct acpi_device_id link_device_ids[] = {
55 {"PNP0C0F", 0},
56 {"", 0},
57};
58
59static struct acpi_scan_handler pci_link_handler = {
60 .ids = link_device_ids,
61 .attach = acpi_pci_link_add,
62 .detach = acpi_pci_link_remove,
63};
64
65/*
66 * If a link is initialized, we never change its active and initialized
67 * later even the link is disable. Instead, we just repick the active irq
68 */
69struct acpi_pci_link_irq {
70 u32 active; /* Current IRQ */
71 u8 triggering; /* All IRQs */
72 u8 polarity; /* All IRQs */
73 u8 resource_type;
74 u8 possible_count;
75 u32 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
76 u8 initialized:1;
77 u8 reserved:7;
78};
79
80struct acpi_pci_link {
81 struct list_head list;
82 struct acpi_device *device;
83 struct acpi_pci_link_irq irq;
84 int refcnt;
85};
86
87static LIST_HEAD(acpi_link_list);
88static DEFINE_MUTEX(acpi_link_lock);
89
90/* --------------------------------------------------------------------------
91 PCI Link Device Management
92 -------------------------------------------------------------------------- */
93
94/*
95 * set context (link) possible list from resource list
96 */
97static acpi_status acpi_pci_link_check_possible(struct acpi_resource *resource,
98 void *context)
99{
100 struct acpi_pci_link *link = context;
101 u32 i;
102
103 switch (resource->type) {
104 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
105 case ACPI_RESOURCE_TYPE_END_TAG:
106 return AE_OK;
107 case ACPI_RESOURCE_TYPE_IRQ:
108 {
109 struct acpi_resource_irq *p = &resource->data.irq;
110 if (!p || !p->interrupt_count) {
111 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
112 "Blank _PRS IRQ resource\n"));
113 return AE_OK;
114 }
115 for (i = 0;
116 (i < p->interrupt_count
117 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
118 if (!p->interrupts[i]) {
119 printk(KERN_WARNING PREFIX
120 "Invalid _PRS IRQ %d\n",
121 p->interrupts[i]);
122 continue;
123 }
124 link->irq.possible[i] = p->interrupts[i];
125 link->irq.possible_count++;
126 }
127 link->irq.triggering = p->triggering;
128 link->irq.polarity = p->polarity;
129 link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ;
130 break;
131 }
132 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
133 {
134 struct acpi_resource_extended_irq *p =
135 &resource->data.extended_irq;
136 if (!p || !p->interrupt_count) {
137 printk(KERN_WARNING PREFIX
138 "Blank _PRS EXT IRQ resource\n");
139 return AE_OK;
140 }
141 for (i = 0;
142 (i < p->interrupt_count
143 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
144 if (!p->interrupts[i]) {
145 printk(KERN_WARNING PREFIX
146 "Invalid _PRS IRQ %d\n",
147 p->interrupts[i]);
148 continue;
149 }
150 link->irq.possible[i] = p->interrupts[i];
151 link->irq.possible_count++;
152 }
153 link->irq.triggering = p->triggering;
154 link->irq.polarity = p->polarity;
155 link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
156 break;
157 }
158 default:
159 printk(KERN_ERR PREFIX "_PRS resource type 0x%x isn't an IRQ\n",
160 resource->type);
161 return AE_OK;
162 }
163
164 return AE_CTRL_TERMINATE;
165}
166
167static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
168{
169 acpi_status status;
170
171 status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
172 acpi_pci_link_check_possible, link);
173 if (ACPI_FAILURE(status)) {
174 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
175 return -ENODEV;
176 }
177
178 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
179 "Found %d possible IRQs\n",
180 link->irq.possible_count));
181
182 return 0;
183}
184
185static acpi_status acpi_pci_link_check_current(struct acpi_resource *resource,
186 void *context)
187{
188 int *irq = context;
189
190 switch (resource->type) {
191 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
192 case ACPI_RESOURCE_TYPE_END_TAG:
193 return AE_OK;
194 case ACPI_RESOURCE_TYPE_IRQ:
195 {
196 struct acpi_resource_irq *p = &resource->data.irq;
197 if (!p || !p->interrupt_count) {
198 /*
199 * IRQ descriptors may have no IRQ# bits set,
200 * particularly those those w/ _STA disabled
201 */
202 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
203 "Blank _CRS IRQ resource\n"));
204 return AE_OK;
205 }
206 *irq = p->interrupts[0];
207 break;
208 }
209 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
210 {
211 struct acpi_resource_extended_irq *p =
212 &resource->data.extended_irq;
213 if (!p || !p->interrupt_count) {
214 /*
215 * extended IRQ descriptors must
216 * return at least 1 IRQ
217 */
218 printk(KERN_WARNING PREFIX
219 "Blank _CRS EXT IRQ resource\n");
220 return AE_OK;
221 }
222 *irq = p->interrupts[0];
223 break;
224 }
225 break;
226 default:
227 printk(KERN_ERR PREFIX "_CRS resource type 0x%x isn't an IRQ\n",
228 resource->type);
229 return AE_OK;
230 }
231
232 return AE_CTRL_TERMINATE;
233}
234
235/*
236 * Run _CRS and set link->irq.active
237 *
238 * return value:
239 * 0 - success
240 * !0 - failure
241 */
242static int acpi_pci_link_get_current(struct acpi_pci_link *link)
243{
244 int result = 0;
245 acpi_status status;
246 int irq = 0;
247
248 link->irq.active = 0;
249
250 /* in practice, status disabled is meaningless, ignore it */
251 if (acpi_strict) {
252 /* Query _STA, set link->device->status */
253 result = acpi_bus_get_status(link->device);
254 if (result) {
255 printk(KERN_ERR PREFIX "Unable to read status\n");
256 goto end;
257 }
258
259 if (!link->device->status.enabled) {
260 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
261 return 0;
262 }
263 }
264
265 /*
266 * Query and parse _CRS to get the current IRQ assignment.
267 */
268
269 status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
270 acpi_pci_link_check_current, &irq);
271 if (ACPI_FAILURE(status)) {
272 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
273 result = -ENODEV;
274 goto end;
275 }
276
277 if (acpi_strict && !irq) {
278 printk(KERN_ERR PREFIX "_CRS returned 0\n");
279 result = -ENODEV;
280 }
281
282 link->irq.active = irq;
283
284 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
285
286 end:
287 return result;
288}
289
290static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
291{
292 int result;
293 acpi_status status;
294 struct {
295 struct acpi_resource res;
296 struct acpi_resource end;
297 } *resource;
298 struct acpi_buffer buffer = { 0, NULL };
299
300 if (!irq)
301 return -EINVAL;
302
303 resource = kzalloc(sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
304 if (!resource)
305 return -ENOMEM;
306
307 buffer.length = sizeof(*resource) + 1;
308 buffer.pointer = resource;
309
310 switch (link->irq.resource_type) {
311 case ACPI_RESOURCE_TYPE_IRQ:
312 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
313 resource->res.length = sizeof(struct acpi_resource);
314 resource->res.data.irq.triggering = link->irq.triggering;
315 resource->res.data.irq.polarity =
316 link->irq.polarity;
317 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
318 resource->res.data.irq.sharable =
319 ACPI_EXCLUSIVE;
320 else
321 resource->res.data.irq.sharable = ACPI_SHARED;
322 resource->res.data.irq.interrupt_count = 1;
323 resource->res.data.irq.interrupts[0] = irq;
324 break;
325
326 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
327 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
328 resource->res.length = sizeof(struct acpi_resource);
329 resource->res.data.extended_irq.producer_consumer =
330 ACPI_CONSUMER;
331 resource->res.data.extended_irq.triggering =
332 link->irq.triggering;
333 resource->res.data.extended_irq.polarity =
334 link->irq.polarity;
335 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
336 resource->res.data.irq.sharable =
337 ACPI_EXCLUSIVE;
338 else
339 resource->res.data.irq.sharable = ACPI_SHARED;
340 resource->res.data.extended_irq.interrupt_count = 1;
341 resource->res.data.extended_irq.interrupts[0] = irq;
342 /* ignore resource_source, it's optional */
343 break;
344 default:
345 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
346 result = -EINVAL;
347 goto end;
348
349 }
350 resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
351 resource->end.length = sizeof(struct acpi_resource);
352
353 /* Attempt to set the resource */
354 status = acpi_set_current_resources(link->device->handle, &buffer);
355
356 /* check for total failure */
357 if (ACPI_FAILURE(status)) {
358 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
359 result = -ENODEV;
360 goto end;
361 }
362
363 /* Query _STA, set device->status */
364 result = acpi_bus_get_status(link->device);
365 if (result) {
366 printk(KERN_ERR PREFIX "Unable to read status\n");
367 goto end;
368 }
369 if (!link->device->status.enabled) {
370 printk(KERN_WARNING PREFIX
371 "%s [%s] disabled and referenced, BIOS bug\n",
372 acpi_device_name(link->device),
373 acpi_device_bid(link->device));
374 }
375
376 /* Query _CRS, set link->irq.active */
377 result = acpi_pci_link_get_current(link);
378 if (result) {
379 goto end;
380 }
381
382 /*
383 * Is current setting not what we set?
384 * set link->irq.active
385 */
386 if (link->irq.active != irq) {
387 /*
388 * policy: when _CRS doesn't return what we just _SRS
389 * assume _SRS worked and override _CRS value.
390 */
391 printk(KERN_WARNING PREFIX
392 "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
393 acpi_device_name(link->device),
394 acpi_device_bid(link->device), link->irq.active, irq);
395 link->irq.active = irq;
396 }
397
398 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
399
400 end:
401 kfree(resource);
402 return result;
403}
404
405/* --------------------------------------------------------------------------
406 PCI Link IRQ Management
407 -------------------------------------------------------------------------- */
408
409/*
410 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
411 * Link Devices to move the PIRQs around to minimize sharing.
412 *
413 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
414 * that the BIOS has already set to active. This is necessary because
415 * ACPI has no automatic means of knowing what ISA IRQs are used. Note that
416 * if the BIOS doesn't set a Link Device active, ACPI needs to program it
417 * even if acpi_irq_nobalance is set.
418 *
419 * A tables of penalties avoids directing PCI interrupts to well known
420 * ISA IRQs. Boot params are available to over-ride the default table:
421 *
422 * List interrupts that are free for PCI use.
423 * acpi_irq_pci=n[,m]
424 *
425 * List interrupts that should not be used for PCI:
426 * acpi_irq_isa=n[,m]
427 *
428 * Note that PCI IRQ routers have a list of possible IRQs,
429 * which may not include the IRQs this table says are available.
430 *
431 * Since this heuristic can't tell the difference between a link
432 * that no device will attach to, vs. a link which may be shared
433 * by multiple active devices -- it is not optimal.
434 *
435 * If interrupt performance is that important, get an IO-APIC system
436 * with a pin dedicated to each device. Or for that matter, an MSI
437 * enabled system.
438 */
439
440#define ACPI_MAX_IRQS 256
441#define ACPI_MAX_ISA_IRQ 16
442
443#define PIRQ_PENALTY_PCI_AVAILABLE (0)
444#define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
445#define PIRQ_PENALTY_PCI_USING (16*16*16)
446#define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16)
447#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
448#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)
449
450static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
451 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
452 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
453 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
454 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */
455 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */
456 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */
457 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */
458 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */
459 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */
460 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */
461 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */
462 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */
463 PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */
464 PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
465 PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
466 PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
467 /* >IRQ15 */
468};
469
470int __init acpi_irq_penalty_init(void)
471{
472 struct acpi_pci_link *link;
473 int i;
474
475 /*
476 * Update penalties to facilitate IRQ balancing.
477 */
478 list_for_each_entry(link, &acpi_link_list, list) {
479
480 /*
481 * reflect the possible and active irqs in the penalty table --
482 * useful for breaking ties.
483 */
484 if (link->irq.possible_count) {
485 int penalty =
486 PIRQ_PENALTY_PCI_POSSIBLE /
487 link->irq.possible_count;
488
489 for (i = 0; i < link->irq.possible_count; i++) {
490 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
491 acpi_irq_penalty[link->irq.
492 possible[i]] +=
493 penalty;
494 }
495
496 } else if (link->irq.active) {
497 acpi_irq_penalty[link->irq.active] +=
498 PIRQ_PENALTY_PCI_POSSIBLE;
499 }
500 }
501
502 return 0;
503}
504
505static int acpi_irq_balance = -1; /* 0: static, 1: balance */
506
507static int acpi_pci_link_allocate(struct acpi_pci_link *link)
508{
509 int irq;
510 int i;
511
512 if (link->irq.initialized) {
513 if (link->refcnt == 0)
514 /* This means the link is disabled but initialized */
515 acpi_pci_link_set(link, link->irq.active);
516 return 0;
517 }
518
519 /*
520 * search for active IRQ in list of possible IRQs.
521 */
522 for (i = 0; i < link->irq.possible_count; ++i) {
523 if (link->irq.active == link->irq.possible[i])
524 break;
525 }
526 /*
527 * forget active IRQ that is not in possible list
528 */
529 if (i == link->irq.possible_count) {
530 if (acpi_strict)
531 printk(KERN_WARNING PREFIX "_CRS %d not found"
532 " in _PRS\n", link->irq.active);
533 link->irq.active = 0;
534 }
535
536 /*
537 * if active found, use it; else pick entry from end of possible list.
538 */
539 if (link->irq.active)
540 irq = link->irq.active;
541 else
542 irq = link->irq.possible[link->irq.possible_count - 1];
543
544 if (acpi_irq_balance || !link->irq.active) {
545 /*
546 * Select the best IRQ. This is done in reverse to promote
547 * the use of IRQs 9, 10, 11, and >15.
548 */
549 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
550 if (acpi_irq_penalty[irq] >
551 acpi_irq_penalty[link->irq.possible[i]])
552 irq = link->irq.possible[i];
553 }
554 }
555 if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) {
556 printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. "
557 "Try pci=noacpi or acpi=off\n",
558 acpi_device_name(link->device),
559 acpi_device_bid(link->device));
560 return -ENODEV;
561 }
562
563 /* Attempt to enable the link device at this IRQ. */
564 if (acpi_pci_link_set(link, irq)) {
565 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
566 "Try pci=noacpi or acpi=off\n",
567 acpi_device_name(link->device),
568 acpi_device_bid(link->device));
569 return -ENODEV;
570 } else {
571 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
572 printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
573 acpi_device_name(link->device),
574 acpi_device_bid(link->device), link->irq.active);
575 }
576
577 link->irq.initialized = 1;
578 return 0;
579}
580
581/*
582 * acpi_pci_link_allocate_irq
583 * success: return IRQ >= 0
584 * failure: return -1
585 */
586int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering,
587 int *polarity, char **name)
588{
589 int result;
590 struct acpi_device *device;
591 struct acpi_pci_link *link;
592
593 result = acpi_bus_get_device(handle, &device);
594 if (result) {
595 printk(KERN_ERR PREFIX "Invalid link device\n");
596 return -1;
597 }
598
599 link = acpi_driver_data(device);
600 if (!link) {
601 printk(KERN_ERR PREFIX "Invalid link context\n");
602 return -1;
603 }
604
605 /* TBD: Support multiple index (IRQ) entries per Link Device */
606 if (index) {
607 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
608 return -1;
609 }
610
611 mutex_lock(&acpi_link_lock);
612 if (acpi_pci_link_allocate(link)) {
613 mutex_unlock(&acpi_link_lock);
614 return -1;
615 }
616
617 if (!link->irq.active) {
618 mutex_unlock(&acpi_link_lock);
619 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
620 return -1;
621 }
622 link->refcnt++;
623 mutex_unlock(&acpi_link_lock);
624
625 if (triggering)
626 *triggering = link->irq.triggering;
627 if (polarity)
628 *polarity = link->irq.polarity;
629 if (name)
630 *name = acpi_device_bid(link->device);
631 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
632 "Link %s is referenced\n",
633 acpi_device_bid(link->device)));
634 return (link->irq.active);
635}
636
637/*
638 * We don't change link's irq information here. After it is reenabled, we
639 * continue use the info
640 */
641int acpi_pci_link_free_irq(acpi_handle handle)
642{
643 struct acpi_device *device;
644 struct acpi_pci_link *link;
645 acpi_status result;
646
647 result = acpi_bus_get_device(handle, &device);
648 if (result) {
649 printk(KERN_ERR PREFIX "Invalid link device\n");
650 return -1;
651 }
652
653 link = acpi_driver_data(device);
654 if (!link) {
655 printk(KERN_ERR PREFIX "Invalid link context\n");
656 return -1;
657 }
658
659 mutex_lock(&acpi_link_lock);
660 if (!link->irq.initialized) {
661 mutex_unlock(&acpi_link_lock);
662 printk(KERN_ERR PREFIX "Link isn't initialized\n");
663 return -1;
664 }
665#ifdef FUTURE_USE
666 /*
667 * The Link reference count allows us to _DISable an unused link
668 * and suspend time, and set it again on resume.
669 * However, 2.6.12 still has irq_router.resume
670 * which blindly restores the link state.
671 * So we disable the reference count method
672 * to prevent duplicate acpi_pci_link_set()
673 * which would harm some systems
674 */
675 link->refcnt--;
676#endif
677 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
678 "Link %s is dereferenced\n",
679 acpi_device_bid(link->device)));
680
681 if (link->refcnt == 0)
682 acpi_evaluate_object(link->device->handle, "_DIS", NULL, NULL);
683
684 mutex_unlock(&acpi_link_lock);
685 return (link->irq.active);
686}
687
688/* --------------------------------------------------------------------------
689 Driver Interface
690 -------------------------------------------------------------------------- */
691
692static int acpi_pci_link_add(struct acpi_device *device,
693 const struct acpi_device_id *not_used)
694{
695 int result;
696 struct acpi_pci_link *link;
697 int i;
698 int found = 0;
699
700 link = kzalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
701 if (!link)
702 return -ENOMEM;
703
704 link->device = device;
705 strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
706 strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
707 device->driver_data = link;
708
709 mutex_lock(&acpi_link_lock);
710 result = acpi_pci_link_get_possible(link);
711 if (result)
712 goto end;
713
714 /* query and set link->irq.active */
715 acpi_pci_link_get_current(link);
716
717 printk(KERN_INFO PREFIX "%s [%s] (IRQs", acpi_device_name(device),
718 acpi_device_bid(device));
719 for (i = 0; i < link->irq.possible_count; i++) {
720 if (link->irq.active == link->irq.possible[i]) {
721 printk(KERN_CONT " *%d", link->irq.possible[i]);
722 found = 1;
723 } else
724 printk(KERN_CONT " %d", link->irq.possible[i]);
725 }
726
727 printk(KERN_CONT ")");
728
729 if (!found)
730 printk(KERN_CONT " *%d", link->irq.active);
731
732 if (!link->device->status.enabled)
733 printk(KERN_CONT ", disabled.");
734
735 printk(KERN_CONT "\n");
736
737 list_add_tail(&link->list, &acpi_link_list);
738
739 end:
740 /* disable all links -- to be activated on use */
741 acpi_evaluate_object(device->handle, "_DIS", NULL, NULL);
742 mutex_unlock(&acpi_link_lock);
743
744 if (result)
745 kfree(link);
746
747 return result < 0 ? result : 1;
748}
749
750static int acpi_pci_link_resume(struct acpi_pci_link *link)
751{
752 if (link->refcnt && link->irq.active && link->irq.initialized)
753 return (acpi_pci_link_set(link, link->irq.active));
754
755 return 0;
756}
757
758static void irqrouter_resume(void)
759{
760 struct acpi_pci_link *link;
761
762 list_for_each_entry(link, &acpi_link_list, list) {
763 acpi_pci_link_resume(link);
764 }
765}
766
767static void acpi_pci_link_remove(struct acpi_device *device)
768{
769 struct acpi_pci_link *link;
770
771 link = acpi_driver_data(device);
772
773 mutex_lock(&acpi_link_lock);
774 list_del(&link->list);
775 mutex_unlock(&acpi_link_lock);
776
777 kfree(link);
778}
779
780/*
781 * modify acpi_irq_penalty[] from cmdline
782 */
783static int __init acpi_irq_penalty_update(char *str, int used)
784{
785 int i;
786
787 for (i = 0; i < 16; i++) {
788 int retval;
789 int irq;
790
791 retval = get_option(&str, &irq);
792
793 if (!retval)
794 break; /* no number found */
795
796 if (irq < 0)
797 continue;
798
799 if (irq >= ARRAY_SIZE(acpi_irq_penalty))
800 continue;
801
802 if (used)
803 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
804 else
805 acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
806
807 if (retval != 2) /* no next number */
808 break;
809 }
810 return 1;
811}
812
813/*
814 * We'd like PNP to call this routine for the
815 * single ISA_USED value for each legacy device.
816 * But instead it calls us with each POSSIBLE setting.
817 * There is no ISA_POSSIBLE weight, so we simply use
818 * the (small) PCI_USING penalty.
819 */
820void acpi_penalize_isa_irq(int irq, int active)
821{
822 if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
823 if (active)
824 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
825 else
826 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
827 }
828}
829
830bool acpi_isa_irq_available(int irq)
831{
832 return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) ||
833 acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS);
834}
835
836/*
837 * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict with
838 * PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be use for
839 * PCI IRQs.
840 */
841void acpi_penalize_sci_irq(int irq, int trigger, int polarity)
842{
843 if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
844 if (trigger != ACPI_MADT_TRIGGER_LEVEL ||
845 polarity != ACPI_MADT_POLARITY_ACTIVE_LOW)
846 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_ALWAYS;
847 else
848 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
849 }
850}
851
852/*
853 * Over-ride default table to reserve additional IRQs for use by ISA
854 * e.g. acpi_irq_isa=5
855 * Useful for telling ACPI how not to interfere with your ISA sound card.
856 */
857static int __init acpi_irq_isa(char *str)
858{
859 return acpi_irq_penalty_update(str, 1);
860}
861
862__setup("acpi_irq_isa=", acpi_irq_isa);
863
864/*
865 * Over-ride default table to free additional IRQs for use by PCI
866 * e.g. acpi_irq_pci=7,15
867 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
868 */
869static int __init acpi_irq_pci(char *str)
870{
871 return acpi_irq_penalty_update(str, 0);
872}
873
874__setup("acpi_irq_pci=", acpi_irq_pci);
875
876static int __init acpi_irq_nobalance_set(char *str)
877{
878 acpi_irq_balance = 0;
879 return 1;
880}
881
882__setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
883
884static int __init acpi_irq_balance_set(char *str)
885{
886 acpi_irq_balance = 1;
887 return 1;
888}
889
890__setup("acpi_irq_balance", acpi_irq_balance_set);
891
892static struct syscore_ops irqrouter_syscore_ops = {
893 .resume = irqrouter_resume,
894};
895
896void __init acpi_pci_link_init(void)
897{
898 if (acpi_noirq)
899 return;
900
901 if (acpi_irq_balance == -1) {
902 /* no command line switch: enable balancing in IOAPIC mode */
903 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC)
904 acpi_irq_balance = 1;
905 else
906 acpi_irq_balance = 0;
907 }
908 register_syscore_ops(&irqrouter_syscore_ops);
909 acpi_scan_add_handler(&pci_link_handler);
910}