ia64/linux-2.6.18-xen.hg

view drivers/acpi/pci_link.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 2afa279661de
children
line source
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 */
32 #include <linux/sysdev.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/types.h>
37 #include <linux/proc_fs.h>
38 #include <linux/spinlock.h>
39 #include <linux/pm.h>
40 #include <linux/pci.h>
41 #include <linux/mutex.h>
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
46 #define _COMPONENT ACPI_PCI_COMPONENT
47 ACPI_MODULE_NAME("pci_link")
48 #define ACPI_PCI_LINK_CLASS "pci_irq_routing"
49 #define ACPI_PCI_LINK_HID "PNP0C0F"
50 #define ACPI_PCI_LINK_DRIVER_NAME "ACPI PCI Interrupt Link Driver"
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 static int acpi_pci_link_add(struct acpi_device *device);
56 static int acpi_pci_link_remove(struct acpi_device *device, int type);
58 static struct acpi_driver acpi_pci_link_driver = {
59 .name = ACPI_PCI_LINK_DRIVER_NAME,
60 .class = ACPI_PCI_LINK_CLASS,
61 .ids = ACPI_PCI_LINK_HID,
62 .ops = {
63 .add = acpi_pci_link_add,
64 .remove = acpi_pci_link_remove,
65 },
66 };
68 /*
69 * If a link is initialized, we never change its active and initialized
70 * later even the link is disable. Instead, we just repick the active irq
71 */
72 struct acpi_pci_link_irq {
73 u8 active; /* Current IRQ */
74 u8 triggering; /* All IRQs */
75 u8 polarity; /* All IRQs */
76 u8 resource_type;
77 u8 possible_count;
78 u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
79 u8 initialized:1;
80 u8 reserved:7;
81 };
83 struct acpi_pci_link {
84 struct list_head node;
85 struct acpi_device *device;
86 struct acpi_pci_link_irq irq;
87 int refcnt;
88 };
90 static struct {
91 int count;
92 struct list_head entries;
93 } acpi_link;
94 DEFINE_MUTEX(acpi_link_lock);
96 /* --------------------------------------------------------------------------
97 PCI Link Device Management
98 -------------------------------------------------------------------------- */
100 /*
101 * set context (link) possible list from resource list
102 */
103 static acpi_status
104 acpi_pci_link_check_possible(struct acpi_resource *resource, void *context)
105 {
106 struct acpi_pci_link *link = (struct acpi_pci_link *)context;
107 u32 i = 0;
110 switch (resource->type) {
111 case ACPI_RESOURCE_TYPE_START_DEPENDENT:
112 return AE_OK;
113 case ACPI_RESOURCE_TYPE_IRQ:
114 {
115 struct acpi_resource_irq *p = &resource->data.irq;
116 if (!p || !p->interrupt_count) {
117 printk(KERN_WARNING PREFIX "Blank IRQ resource\n");
118 return AE_OK;
119 }
120 for (i = 0;
121 (i < p->interrupt_count
122 && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) {
123 if (!p->interrupts[i]) {
124 printk(KERN_WARNING PREFIX "Invalid 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 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 "Invalid IRQ %d\n",
150 p->interrupts[i]);
151 continue;
152 }
153 link->irq.possible[i] = p->interrupts[i];
154 link->irq.possible_count++;
155 }
156 link->irq.triggering = p->triggering;
157 link->irq.polarity = p->polarity;
158 link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
159 break;
160 }
161 default:
162 printk(KERN_ERR PREFIX "Resource is not an IRQ entry\n");
163 return AE_OK;
164 }
166 return AE_CTRL_TERMINATE;
167 }
169 static int acpi_pci_link_get_possible(struct acpi_pci_link *link)
170 {
171 acpi_status status;
174 if (!link)
175 return -EINVAL;
177 status = acpi_walk_resources(link->device->handle, METHOD_NAME__PRS,
178 acpi_pci_link_check_possible, link);
179 if (ACPI_FAILURE(status)) {
180 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRS"));
181 return -ENODEV;
182 }
184 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
185 "Found %d possible IRQs\n",
186 link->irq.possible_count));
188 return 0;
189 }
191 static acpi_status
192 acpi_pci_link_check_current(struct acpi_resource *resource, void *context)
193 {
194 int *irq = (int *)context;
197 switch (resource->type) {
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 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 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 "Resource %d isn't an IRQ\n", resource->type);
232 case ACPI_RESOURCE_TYPE_END_TAG:
233 return AE_OK;
234 }
235 return AE_CTRL_TERMINATE;
236 }
238 /*
239 * Run _CRS and set link->irq.active
240 *
241 * return value:
242 * 0 - success
243 * !0 - failure
244 */
245 static int acpi_pci_link_get_current(struct acpi_pci_link *link)
246 {
247 int result = 0;
248 acpi_status status = AE_OK;
249 int irq = 0;
251 if (!link)
252 return -EINVAL;
254 link->irq.active = 0;
256 /* in practice, status disabled is meaningless, ignore it */
257 if (acpi_strict) {
258 /* Query _STA, set link->device->status */
259 result = acpi_bus_get_status(link->device);
260 if (result) {
261 printk(KERN_ERR PREFIX "Unable to read status\n");
262 goto end;
263 }
265 if (!link->device->status.enabled) {
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link disabled\n"));
267 return 0;
268 }
269 }
271 /*
272 * Query and parse _CRS to get the current IRQ assignment.
273 */
275 status = acpi_walk_resources(link->device->handle, METHOD_NAME__CRS,
276 acpi_pci_link_check_current, &irq);
277 if (ACPI_FAILURE(status)) {
278 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _CRS"));
279 result = -ENODEV;
280 goto end;
281 }
283 if (acpi_strict && !irq) {
284 printk(KERN_ERR PREFIX "_CRS returned 0\n");
285 result = -ENODEV;
286 }
288 link->irq.active = irq;
290 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Link at IRQ %d \n", link->irq.active));
292 end:
293 return result;
294 }
296 static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
297 {
298 int result = 0;
299 acpi_status status = AE_OK;
300 struct {
301 struct acpi_resource res;
302 struct acpi_resource end;
303 } *resource;
304 struct acpi_buffer buffer = { 0, NULL };
307 if (!link || !irq)
308 return -EINVAL;
310 resource = kmalloc(sizeof(*resource) + 1, GFP_ATOMIC);
311 if (!resource)
312 return -ENOMEM;
314 memset(resource, 0, sizeof(*resource) + 1);
315 buffer.length = sizeof(*resource) + 1;
316 buffer.pointer = resource;
318 switch (link->irq.resource_type) {
319 case ACPI_RESOURCE_TYPE_IRQ:
320 resource->res.type = ACPI_RESOURCE_TYPE_IRQ;
321 resource->res.length = sizeof(struct acpi_resource);
322 resource->res.data.irq.triggering = link->irq.triggering;
323 resource->res.data.irq.polarity =
324 link->irq.polarity;
325 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
326 resource->res.data.irq.sharable =
327 ACPI_EXCLUSIVE;
328 else
329 resource->res.data.irq.sharable = ACPI_SHARED;
330 resource->res.data.irq.interrupt_count = 1;
331 resource->res.data.irq.interrupts[0] = irq;
332 break;
334 case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
335 resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ;
336 resource->res.length = sizeof(struct acpi_resource);
337 resource->res.data.extended_irq.producer_consumer =
338 ACPI_CONSUMER;
339 resource->res.data.extended_irq.triggering =
340 link->irq.triggering;
341 resource->res.data.extended_irq.polarity =
342 link->irq.polarity;
343 if (link->irq.triggering == ACPI_EDGE_SENSITIVE)
344 resource->res.data.irq.sharable =
345 ACPI_EXCLUSIVE;
346 else
347 resource->res.data.irq.sharable = ACPI_SHARED;
348 resource->res.data.extended_irq.interrupt_count = 1;
349 resource->res.data.extended_irq.interrupts[0] = irq;
350 /* ignore resource_source, it's optional */
351 break;
352 default:
353 printk(KERN_ERR PREFIX "Invalid Resource_type %d\n", link->irq.resource_type);
354 result = -EINVAL;
355 goto end;
357 }
358 resource->end.type = ACPI_RESOURCE_TYPE_END_TAG;
360 /* Attempt to set the resource */
361 status = acpi_set_current_resources(link->device->handle, &buffer);
363 /* check for total failure */
364 if (ACPI_FAILURE(status)) {
365 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SRS"));
366 result = -ENODEV;
367 goto end;
368 }
370 /* Query _STA, set device->status */
371 result = acpi_bus_get_status(link->device);
372 if (result) {
373 printk(KERN_ERR PREFIX "Unable to read status\n");
374 goto end;
375 }
376 if (!link->device->status.enabled) {
377 printk(KERN_WARNING PREFIX
378 "%s [%s] disabled and referenced, BIOS bug\n",
379 acpi_device_name(link->device),
380 acpi_device_bid(link->device));
381 }
383 /* Query _CRS, set link->irq.active */
384 result = acpi_pci_link_get_current(link);
385 if (result) {
386 goto end;
387 }
389 /*
390 * Is current setting not what we set?
391 * set link->irq.active
392 */
393 if (link->irq.active != irq) {
394 /*
395 * policy: when _CRS doesn't return what we just _SRS
396 * assume _SRS worked and override _CRS value.
397 */
398 printk(KERN_WARNING PREFIX
399 "%s [%s] BIOS reported IRQ %d, using IRQ %d\n",
400 acpi_device_name(link->device),
401 acpi_device_bid(link->device), link->irq.active, irq);
402 link->irq.active = irq;
403 }
405 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Set IRQ %d\n", link->irq.active));
407 end:
408 kfree(resource);
409 return result;
410 }
412 /* --------------------------------------------------------------------------
413 PCI Link IRQ Management
414 -------------------------------------------------------------------------- */
416 /*
417 * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt
418 * Link Devices to move the PIRQs around to minimize sharing.
419 *
420 * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs
421 * that the BIOS has already set to active. This is necessary because
422 * ACPI has no automatic means of knowing what ISA IRQs are used. Note that
423 * if the BIOS doesn't set a Link Device active, ACPI needs to program it
424 * even if acpi_irq_nobalance is set.
425 *
426 * A tables of penalties avoids directing PCI interrupts to well known
427 * ISA IRQs. Boot params are available to over-ride the default table:
428 *
429 * List interrupts that are free for PCI use.
430 * acpi_irq_pci=n[,m]
431 *
432 * List interrupts that should not be used for PCI:
433 * acpi_irq_isa=n[,m]
434 *
435 * Note that PCI IRQ routers have a list of possible IRQs,
436 * which may not include the IRQs this table says are available.
437 *
438 * Since this heuristic can't tell the difference between a link
439 * that no device will attach to, vs. a link which may be shared
440 * by multiple active devices -- it is not optimal.
441 *
442 * If interrupt performance is that important, get an IO-APIC system
443 * with a pin dedicated to each device. Or for that matter, an MSI
444 * enabled system.
445 */
447 #define ACPI_MAX_IRQS 256
448 #define ACPI_MAX_ISA_IRQ 16
450 #define PIRQ_PENALTY_PCI_AVAILABLE (0)
451 #define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
452 #define PIRQ_PENALTY_PCI_USING (16*16*16)
453 #define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16)
454 #define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
455 #define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)
457 static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
458 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
459 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
460 PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
461 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */
462 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */
463 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */
464 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */
465 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */
466 PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */
467 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ9 PCI, often acpi */
468 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ10 PCI */
469 PIRQ_PENALTY_PCI_AVAILABLE, /* IRQ11 PCI */
470 PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */
471 PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
472 PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
473 PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
474 /* >IRQ15 */
475 };
477 int __init acpi_irq_penalty_init(void)
478 {
479 struct list_head *node = NULL;
480 struct acpi_pci_link *link = NULL;
481 int i = 0;
484 /*
485 * Update penalties to facilitate IRQ balancing.
486 */
487 list_for_each(node, &acpi_link.entries) {
489 link = list_entry(node, struct acpi_pci_link, node);
490 if (!link) {
491 printk(KERN_ERR PREFIX "Invalid link context\n");
492 continue;
493 }
495 /*
496 * reflect the possible and active irqs in the penalty table --
497 * useful for breaking ties.
498 */
499 if (link->irq.possible_count) {
500 int penalty =
501 PIRQ_PENALTY_PCI_POSSIBLE /
502 link->irq.possible_count;
504 for (i = 0; i < link->irq.possible_count; i++) {
505 if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
506 acpi_irq_penalty[link->irq.
507 possible[i]] +=
508 penalty;
509 }
511 } else if (link->irq.active) {
512 acpi_irq_penalty[link->irq.active] +=
513 PIRQ_PENALTY_PCI_POSSIBLE;
514 }
515 }
516 /* Add a penalty for the SCI */
517 acpi_irq_penalty[acpi_fadt.sci_int] += PIRQ_PENALTY_PCI_USING;
519 return 0;
520 }
522 static int acpi_irq_balance; /* 0: static, 1: balance */
524 static int acpi_pci_link_allocate(struct acpi_pci_link *link)
525 {
526 int irq;
527 int i;
530 if (link->irq.initialized) {
531 if (link->refcnt == 0)
532 /* This means the link is disabled but initialized */
533 acpi_pci_link_set(link, link->irq.active);
534 return 0;
535 }
537 /*
538 * search for active IRQ in list of possible IRQs.
539 */
540 for (i = 0; i < link->irq.possible_count; ++i) {
541 if (link->irq.active == link->irq.possible[i])
542 break;
543 }
544 /*
545 * forget active IRQ that is not in possible list
546 */
547 if (i == link->irq.possible_count) {
548 if (acpi_strict)
549 printk(KERN_WARNING PREFIX "_CRS %d not found"
550 " in _PRS\n", link->irq.active);
551 link->irq.active = 0;
552 }
554 /*
555 * if active found, use it; else pick entry from end of possible list.
556 */
557 if (link->irq.active) {
558 irq = link->irq.active;
559 } else {
560 irq = link->irq.possible[link->irq.possible_count - 1];
561 }
563 if (acpi_irq_balance || !link->irq.active) {
564 /*
565 * Select the best IRQ. This is done in reverse to promote
566 * the use of IRQs 9, 10, 11, and >15.
567 */
568 for (i = (link->irq.possible_count - 1); i >= 0; i--) {
569 if (acpi_irq_penalty[irq] >
570 acpi_irq_penalty[link->irq.possible[i]])
571 irq = link->irq.possible[i];
572 }
573 }
575 /* Attempt to enable the link device at this IRQ. */
576 if (acpi_pci_link_set(link, irq)) {
577 printk(KERN_ERR PREFIX "Unable to set IRQ for %s [%s]. "
578 "Try pci=noacpi or acpi=off\n",
579 acpi_device_name(link->device),
580 acpi_device_bid(link->device));
581 return -ENODEV;
582 } else {
583 acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
584 printk(PREFIX "%s [%s] enabled at IRQ %d\n",
585 acpi_device_name(link->device),
586 acpi_device_bid(link->device), link->irq.active);
587 }
589 link->irq.initialized = 1;
591 return 0;
592 }
594 /*
595 * acpi_pci_link_allocate_irq
596 * success: return IRQ >= 0
597 * failure: return -1
598 */
600 int
601 acpi_pci_link_allocate_irq(acpi_handle handle,
602 int index,
603 int *triggering, int *polarity, char **name)
604 {
605 int result = 0;
606 struct acpi_device *device = NULL;
607 struct acpi_pci_link *link = NULL;
610 result = acpi_bus_get_device(handle, &device);
611 if (result) {
612 printk(KERN_ERR PREFIX "Invalid link device\n");
613 return -1;
614 }
616 link = (struct acpi_pci_link *)acpi_driver_data(device);
617 if (!link) {
618 printk(KERN_ERR PREFIX "Invalid link context\n");
619 return -1;
620 }
622 /* TBD: Support multiple index (IRQ) entries per Link Device */
623 if (index) {
624 printk(KERN_ERR PREFIX "Invalid index %d\n", index);
625 return -1;
626 }
628 mutex_lock(&acpi_link_lock);
629 if (acpi_pci_link_allocate(link)) {
630 mutex_unlock(&acpi_link_lock);
631 return -1;
632 }
634 if (!link->irq.active) {
635 mutex_unlock(&acpi_link_lock);
636 printk(KERN_ERR PREFIX "Link active IRQ is 0!\n");
637 return -1;
638 }
639 link->refcnt++;
640 mutex_unlock(&acpi_link_lock);
642 if (triggering)
643 *triggering = link->irq.triggering;
644 if (polarity)
645 *polarity = link->irq.polarity;
646 if (name)
647 *name = acpi_device_bid(link->device);
648 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
649 "Link %s is referenced\n",
650 acpi_device_bid(link->device)));
651 return (link->irq.active);
652 }
654 /*
655 * We don't change link's irq information here. After it is reenabled, we
656 * continue use the info
657 */
658 int acpi_pci_link_free_irq(acpi_handle handle)
659 {
660 struct acpi_device *device = NULL;
661 struct acpi_pci_link *link = NULL;
662 acpi_status result;
665 result = acpi_bus_get_device(handle, &device);
666 if (result) {
667 printk(KERN_ERR PREFIX "Invalid link device\n");
668 return -1;
669 }
671 link = (struct acpi_pci_link *)acpi_driver_data(device);
672 if (!link) {
673 printk(KERN_ERR PREFIX "Invalid link context\n");
674 return -1;
675 }
677 mutex_lock(&acpi_link_lock);
678 if (!link->irq.initialized) {
679 mutex_unlock(&acpi_link_lock);
680 printk(KERN_ERR PREFIX "Link isn't initialized\n");
681 return -1;
682 }
683 #ifdef FUTURE_USE
684 /*
685 * The Link reference count allows us to _DISable an unused link
686 * and suspend time, and set it again on resume.
687 * However, 2.6.12 still has irq_router.resume
688 * which blindly restores the link state.
689 * So we disable the reference count method
690 * to prevent duplicate acpi_pci_link_set()
691 * which would harm some systems
692 */
693 link->refcnt--;
694 #endif
695 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
696 "Link %s is dereferenced\n",
697 acpi_device_bid(link->device)));
699 if (link->refcnt == 0) {
700 acpi_ut_evaluate_object(link->device->handle, "_DIS", 0, NULL);
701 }
702 mutex_unlock(&acpi_link_lock);
703 return (link->irq.active);
704 }
706 /* --------------------------------------------------------------------------
707 Driver Interface
708 -------------------------------------------------------------------------- */
710 static int acpi_pci_link_add(struct acpi_device *device)
711 {
712 int result = 0;
713 struct acpi_pci_link *link = NULL;
714 int i = 0;
715 int found = 0;
718 if (!device)
719 return -EINVAL;
721 link = kmalloc(sizeof(struct acpi_pci_link), GFP_KERNEL);
722 if (!link)
723 return -ENOMEM;
724 memset(link, 0, sizeof(struct acpi_pci_link));
726 link->device = device;
727 strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME);
728 strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS);
729 acpi_driver_data(device) = link;
731 mutex_lock(&acpi_link_lock);
732 result = acpi_pci_link_get_possible(link);
733 if (result)
734 goto end;
736 /* query and set link->irq.active */
737 acpi_pci_link_get_current(link);
739 printk(PREFIX "%s [%s] (IRQs", acpi_device_name(device),
740 acpi_device_bid(device));
741 for (i = 0; i < link->irq.possible_count; i++) {
742 if (link->irq.active == link->irq.possible[i]) {
743 printk(" *%d", link->irq.possible[i]);
744 found = 1;
745 } else
746 printk(" %d", link->irq.possible[i]);
747 }
749 printk(")");
751 if (!found)
752 printk(" *%d", link->irq.active);
754 if (!link->device->status.enabled)
755 printk(", disabled.");
757 printk("\n");
759 /* TBD: Acquire/release lock */
760 list_add_tail(&link->node, &acpi_link.entries);
761 acpi_link.count++;
763 end:
764 /* disable all links -- to be activated on use */
765 acpi_ut_evaluate_object(device->handle, "_DIS", 0, NULL);
766 mutex_unlock(&acpi_link_lock);
768 if (result)
769 kfree(link);
771 return result;
772 }
774 static int acpi_pci_link_resume(struct acpi_pci_link *link)
775 {
777 if (link->refcnt && link->irq.active && link->irq.initialized)
778 return (acpi_pci_link_set(link, link->irq.active));
779 else
780 return 0;
781 }
783 static int irqrouter_resume(struct sys_device *dev)
784 {
785 struct list_head *node = NULL;
786 struct acpi_pci_link *link = NULL;
789 /* Make sure SCI is enabled again (Apple firmware bug?) */
790 acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1, ACPI_MTX_DO_NOT_LOCK);
792 list_for_each(node, &acpi_link.entries) {
793 link = list_entry(node, struct acpi_pci_link, node);
794 if (!link) {
795 printk(KERN_ERR PREFIX "Invalid link context\n");
796 continue;
797 }
798 acpi_pci_link_resume(link);
799 }
800 return 0;
801 }
803 static int acpi_pci_link_remove(struct acpi_device *device, int type)
804 {
805 struct acpi_pci_link *link = NULL;
808 if (!device || !acpi_driver_data(device))
809 return -EINVAL;
811 link = (struct acpi_pci_link *)acpi_driver_data(device);
813 mutex_lock(&acpi_link_lock);
814 list_del(&link->node);
815 mutex_unlock(&acpi_link_lock);
817 kfree(link);
819 return 0;
820 }
822 /*
823 * modify acpi_irq_penalty[] from cmdline
824 */
825 static int __init acpi_irq_penalty_update(char *str, int used)
826 {
827 int i;
829 for (i = 0; i < 16; i++) {
830 int retval;
831 int irq;
833 retval = get_option(&str, &irq);
835 if (!retval)
836 break; /* no number found */
838 if (irq < 0)
839 continue;
841 if (irq >= ACPI_MAX_IRQS)
842 continue;
844 if (used)
845 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
846 else
847 acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
849 if (retval != 2) /* no next number */
850 break;
851 }
852 return 1;
853 }
855 /*
856 * We'd like PNP to call this routine for the
857 * single ISA_USED value for each legacy device.
858 * But instead it calls us with each POSSIBLE setting.
859 * There is no ISA_POSSIBLE weight, so we simply use
860 * the (small) PCI_USING penalty.
861 */
862 void acpi_penalize_isa_irq(int irq, int active)
863 {
864 if (active)
865 acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
866 else
867 acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
868 }
870 /*
871 * Over-ride default table to reserve additional IRQs for use by ISA
872 * e.g. acpi_irq_isa=5
873 * Useful for telling ACPI how not to interfere with your ISA sound card.
874 */
875 static int __init acpi_irq_isa(char *str)
876 {
877 return acpi_irq_penalty_update(str, 1);
878 }
880 __setup("acpi_irq_isa=", acpi_irq_isa);
882 /*
883 * Over-ride default table to free additional IRQs for use by PCI
884 * e.g. acpi_irq_pci=7,15
885 * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing.
886 */
887 static int __init acpi_irq_pci(char *str)
888 {
889 return acpi_irq_penalty_update(str, 0);
890 }
892 __setup("acpi_irq_pci=", acpi_irq_pci);
894 static int __init acpi_irq_nobalance_set(char *str)
895 {
896 acpi_irq_balance = 0;
897 return 1;
898 }
900 __setup("acpi_irq_nobalance", acpi_irq_nobalance_set);
902 int __init acpi_irq_balance_set(char *str)
903 {
904 acpi_irq_balance = 1;
905 return 1;
906 }
908 __setup("acpi_irq_balance", acpi_irq_balance_set);
910 /* FIXME: we will remove this interface after all drivers call pci_disable_device */
911 static struct sysdev_class irqrouter_sysdev_class = {
912 set_kset_name("irqrouter"),
913 .resume = irqrouter_resume,
914 };
916 static struct sys_device device_irqrouter = {
917 .id = 0,
918 .cls = &irqrouter_sysdev_class,
919 };
921 static int __init irqrouter_init_sysfs(void)
922 {
923 int error;
926 if (acpi_disabled || acpi_noirq)
927 return 0;
929 error = sysdev_class_register(&irqrouter_sysdev_class);
930 if (!error)
931 error = sysdev_register(&device_irqrouter);
933 return error;
934 }
936 device_initcall(irqrouter_init_sysfs);
938 static int __init acpi_pci_link_init(void)
939 {
941 if (acpi_noirq)
942 return 0;
944 acpi_link.count = 0;
945 INIT_LIST_HEAD(&acpi_link.entries);
947 if (acpi_bus_register_driver(&acpi_pci_link_driver) < 0)
948 return -ENODEV;
950 return 0;
951 }
953 subsys_initcall(acpi_pci_link_init);