1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * pci_link.c - ACPI PCI Interrupt Link Device Driver ($Revision: 34 $) |
4 | * |
5 | * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> |
6 | * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> |
7 | * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de> |
8 | * |
9 | * TBD: |
10 | * 1. Support more than one IRQ resource entry per link device (index). |
11 | * 2. Implement start/stop mechanism and use ACPI Bus Driver facilities |
12 | * for IRQ management (e.g. start()->_SRS). |
13 | */ |
14 | |
15 | #define pr_fmt(fmt) "ACPI: PCI: " fmt |
16 | |
17 | #include <linux/syscore_ops.h> |
18 | #include <linux/kernel.h> |
19 | #include <linux/module.h> |
20 | #include <linux/init.h> |
21 | #include <linux/types.h> |
22 | #include <linux/spinlock.h> |
23 | #include <linux/pm.h> |
24 | #include <linux/pci.h> |
25 | #include <linux/mutex.h> |
26 | #include <linux/slab.h> |
27 | #include <linux/acpi.h> |
28 | #include <linux/irq.h> |
29 | |
30 | #include "internal.h" |
31 | |
32 | #define ACPI_PCI_LINK_CLASS "pci_irq_routing" |
33 | #define ACPI_PCI_LINK_DEVICE_NAME "PCI Interrupt Link" |
34 | #define ACPI_PCI_LINK_MAX_POSSIBLE 16 |
35 | |
36 | static int acpi_pci_link_add(struct acpi_device *device, |
37 | const struct acpi_device_id *not_used); |
38 | static void acpi_pci_link_remove(struct acpi_device *device); |
39 | |
40 | static const struct acpi_device_id link_device_ids[] = { |
41 | {"PNP0C0F" , 0}, |
42 | {"" , 0}, |
43 | }; |
44 | |
45 | static struct acpi_scan_handler pci_link_handler = { |
46 | .ids = link_device_ids, |
47 | .attach = acpi_pci_link_add, |
48 | .detach = acpi_pci_link_remove, |
49 | }; |
50 | |
51 | /* |
52 | * If a link is initialized, we never change its active and initialized |
53 | * later even the link is disable. Instead, we just repick the active irq |
54 | */ |
55 | struct acpi_pci_link_irq { |
56 | u32 active; /* Current IRQ */ |
57 | u8 triggering; /* All IRQs */ |
58 | u8 polarity; /* All IRQs */ |
59 | u8 resource_type; |
60 | u8 possible_count; |
61 | u32 possible[ACPI_PCI_LINK_MAX_POSSIBLE]; |
62 | u8 initialized:1; |
63 | u8 reserved:7; |
64 | }; |
65 | |
66 | struct acpi_pci_link { |
67 | struct list_head list; |
68 | struct acpi_device *device; |
69 | struct acpi_pci_link_irq irq; |
70 | int refcnt; |
71 | }; |
72 | |
73 | static LIST_HEAD(acpi_link_list); |
74 | static DEFINE_MUTEX(acpi_link_lock); |
75 | static int sci_irq = -1, sci_penalty; |
76 | |
77 | /* -------------------------------------------------------------------------- |
78 | PCI Link Device Management |
79 | -------------------------------------------------------------------------- */ |
80 | |
81 | /* |
82 | * set context (link) possible list from resource list |
83 | */ |
84 | static acpi_status acpi_pci_link_check_possible(struct acpi_resource *resource, |
85 | void *context) |
86 | { |
87 | struct acpi_pci_link *link = context; |
88 | acpi_handle handle = link->device->handle; |
89 | u32 i; |
90 | |
91 | switch (resource->type) { |
92 | case ACPI_RESOURCE_TYPE_START_DEPENDENT: |
93 | case ACPI_RESOURCE_TYPE_END_TAG: |
94 | return AE_OK; |
95 | case ACPI_RESOURCE_TYPE_IRQ: |
96 | { |
97 | struct acpi_resource_irq *p = &resource->data.irq; |
98 | if (!p->interrupt_count) { |
99 | acpi_handle_debug(handle, |
100 | "Blank _PRS IRQ resource\n" ); |
101 | return AE_OK; |
102 | } |
103 | for (i = 0; |
104 | (i < p->interrupt_count |
105 | && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) { |
106 | if (!p->interrupts[i]) { |
107 | acpi_handle_debug(handle, |
108 | "Invalid _PRS IRQ %d\n" , |
109 | p->interrupts[i]); |
110 | continue; |
111 | } |
112 | link->irq.possible[i] = p->interrupts[i]; |
113 | link->irq.possible_count++; |
114 | } |
115 | link->irq.triggering = p->triggering; |
116 | link->irq.polarity = p->polarity; |
117 | link->irq.resource_type = ACPI_RESOURCE_TYPE_IRQ; |
118 | break; |
119 | } |
120 | case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: |
121 | { |
122 | struct acpi_resource_extended_irq *p = |
123 | &resource->data.extended_irq; |
124 | if (!p->interrupt_count) { |
125 | acpi_handle_debug(handle, |
126 | "Blank _PRS EXT IRQ resource\n" ); |
127 | return AE_OK; |
128 | } |
129 | for (i = 0; |
130 | (i < p->interrupt_count |
131 | && i < ACPI_PCI_LINK_MAX_POSSIBLE); i++) { |
132 | if (!p->interrupts[i]) { |
133 | acpi_handle_debug(handle, |
134 | "Invalid _PRS IRQ %d\n" , |
135 | p->interrupts[i]); |
136 | continue; |
137 | } |
138 | link->irq.possible[i] = p->interrupts[i]; |
139 | link->irq.possible_count++; |
140 | } |
141 | link->irq.triggering = p->triggering; |
142 | link->irq.polarity = p->polarity; |
143 | link->irq.resource_type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ; |
144 | break; |
145 | } |
146 | default: |
147 | acpi_handle_debug(handle, "_PRS resource type 0x%x is not IRQ\n" , |
148 | resource->type); |
149 | return AE_OK; |
150 | } |
151 | |
152 | return AE_CTRL_TERMINATE; |
153 | } |
154 | |
155 | static int acpi_pci_link_get_possible(struct acpi_pci_link *link) |
156 | { |
157 | acpi_handle handle = link->device->handle; |
158 | acpi_status status; |
159 | |
160 | status = acpi_walk_resources(device: handle, METHOD_NAME__PRS, |
161 | user_function: acpi_pci_link_check_possible, context: link); |
162 | if (ACPI_FAILURE(status)) { |
163 | acpi_handle_debug(handle, "_PRS not present or invalid" ); |
164 | return 0; |
165 | } |
166 | |
167 | acpi_handle_debug(handle, "Found %d possible IRQs\n" , |
168 | link->irq.possible_count); |
169 | |
170 | return 0; |
171 | } |
172 | |
173 | static acpi_status acpi_pci_link_check_current(struct acpi_resource *resource, |
174 | void *context) |
175 | { |
176 | int *irq = context; |
177 | |
178 | switch (resource->type) { |
179 | case ACPI_RESOURCE_TYPE_START_DEPENDENT: |
180 | case ACPI_RESOURCE_TYPE_END_TAG: |
181 | return AE_OK; |
182 | case ACPI_RESOURCE_TYPE_IRQ: |
183 | { |
184 | struct acpi_resource_irq *p = &resource->data.irq; |
185 | if (!p->interrupt_count) { |
186 | /* |
187 | * IRQ descriptors may have no IRQ# bits set, |
188 | * particularly those w/ _STA disabled |
189 | */ |
190 | pr_debug("Blank _CRS IRQ resource\n" ); |
191 | return AE_OK; |
192 | } |
193 | *irq = p->interrupts[0]; |
194 | break; |
195 | } |
196 | case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: |
197 | { |
198 | struct acpi_resource_extended_irq *p = |
199 | &resource->data.extended_irq; |
200 | if (!p->interrupt_count) { |
201 | /* |
202 | * extended IRQ descriptors must |
203 | * return at least 1 IRQ |
204 | */ |
205 | pr_debug("Blank _CRS EXT IRQ resource\n" ); |
206 | return AE_OK; |
207 | } |
208 | *irq = p->interrupts[0]; |
209 | break; |
210 | } |
211 | break; |
212 | default: |
213 | pr_debug("_CRS resource type 0x%x is not IRQ\n" , |
214 | resource->type); |
215 | return AE_OK; |
216 | } |
217 | |
218 | return AE_CTRL_TERMINATE; |
219 | } |
220 | |
221 | /* |
222 | * Run _CRS and set link->irq.active |
223 | * |
224 | * return value: |
225 | * 0 - success |
226 | * !0 - failure |
227 | */ |
228 | static int acpi_pci_link_get_current(struct acpi_pci_link *link) |
229 | { |
230 | acpi_handle handle = link->device->handle; |
231 | acpi_status status; |
232 | int result = 0; |
233 | int irq = 0; |
234 | |
235 | link->irq.active = 0; |
236 | |
237 | /* in practice, status disabled is meaningless, ignore it */ |
238 | if (acpi_strict) { |
239 | /* Query _STA, set link->device->status */ |
240 | result = acpi_bus_get_status(device: link->device); |
241 | if (result) { |
242 | acpi_handle_err(handle, "Unable to read status\n" ); |
243 | goto end; |
244 | } |
245 | |
246 | if (!link->device->status.enabled) { |
247 | acpi_handle_debug(handle, "Link disabled\n" ); |
248 | return 0; |
249 | } |
250 | } |
251 | |
252 | /* |
253 | * Query and parse _CRS to get the current IRQ assignment. |
254 | */ |
255 | |
256 | status = acpi_walk_resources(device: handle, METHOD_NAME__CRS, |
257 | user_function: acpi_pci_link_check_current, context: &irq); |
258 | if (ACPI_FAILURE(status)) { |
259 | acpi_evaluation_failure_warn(handle, name: "_CRS" , status); |
260 | result = -ENODEV; |
261 | goto end; |
262 | } |
263 | |
264 | if (acpi_strict && !irq) { |
265 | acpi_handle_err(handle, "_CRS returned 0\n" ); |
266 | result = -ENODEV; |
267 | } |
268 | |
269 | link->irq.active = irq; |
270 | |
271 | acpi_handle_debug(handle, "Link at IRQ %d \n" , link->irq.active); |
272 | |
273 | end: |
274 | return result; |
275 | } |
276 | |
277 | static int acpi_pci_link_set(struct acpi_pci_link *link, int irq) |
278 | { |
279 | struct { |
280 | struct acpi_resource res; |
281 | struct acpi_resource end; |
282 | } *resource; |
283 | struct acpi_buffer buffer = { 0, NULL }; |
284 | acpi_handle handle = link->device->handle; |
285 | acpi_status status; |
286 | int result; |
287 | |
288 | if (!irq) |
289 | return -EINVAL; |
290 | |
291 | resource = kzalloc(size: sizeof(*resource) + 1, irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL); |
292 | if (!resource) |
293 | return -ENOMEM; |
294 | |
295 | buffer.length = sizeof(*resource) + 1; |
296 | buffer.pointer = resource; |
297 | |
298 | switch (link->irq.resource_type) { |
299 | case ACPI_RESOURCE_TYPE_IRQ: |
300 | resource->res.type = ACPI_RESOURCE_TYPE_IRQ; |
301 | resource->res.length = sizeof(struct acpi_resource); |
302 | resource->res.data.irq.triggering = link->irq.triggering; |
303 | resource->res.data.irq.polarity = |
304 | link->irq.polarity; |
305 | if (link->irq.triggering == ACPI_EDGE_SENSITIVE) |
306 | resource->res.data.irq.shareable = |
307 | ACPI_EXCLUSIVE; |
308 | else |
309 | resource->res.data.irq.shareable = ACPI_SHARED; |
310 | resource->res.data.irq.interrupt_count = 1; |
311 | resource->res.data.irq.interrupts[0] = irq; |
312 | break; |
313 | |
314 | case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: |
315 | resource->res.type = ACPI_RESOURCE_TYPE_EXTENDED_IRQ; |
316 | resource->res.length = sizeof(struct acpi_resource); |
317 | resource->res.data.extended_irq.producer_consumer = |
318 | ACPI_CONSUMER; |
319 | resource->res.data.extended_irq.triggering = |
320 | link->irq.triggering; |
321 | resource->res.data.extended_irq.polarity = |
322 | link->irq.polarity; |
323 | if (link->irq.triggering == ACPI_EDGE_SENSITIVE) |
324 | resource->res.data.extended_irq.shareable = |
325 | ACPI_EXCLUSIVE; |
326 | else |
327 | resource->res.data.extended_irq.shareable = ACPI_SHARED; |
328 | resource->res.data.extended_irq.interrupt_count = 1; |
329 | resource->res.data.extended_irq.interrupts[0] = irq; |
330 | /* ignore resource_source, it's optional */ |
331 | break; |
332 | default: |
333 | acpi_handle_err(handle, "Invalid resource type %d\n" , |
334 | link->irq.resource_type); |
335 | result = -EINVAL; |
336 | goto end; |
337 | |
338 | } |
339 | resource->end.type = ACPI_RESOURCE_TYPE_END_TAG; |
340 | resource->end.length = sizeof(struct acpi_resource); |
341 | |
342 | /* Attempt to set the resource */ |
343 | status = acpi_set_current_resources(device: link->device->handle, in_buffer: &buffer); |
344 | |
345 | /* check for total failure */ |
346 | if (ACPI_FAILURE(status)) { |
347 | acpi_evaluation_failure_warn(handle, name: "_SRS" , status); |
348 | result = -ENODEV; |
349 | goto end; |
350 | } |
351 | |
352 | /* Query _STA, set device->status */ |
353 | result = acpi_bus_get_status(device: link->device); |
354 | if (result) { |
355 | acpi_handle_err(handle, "Unable to read status\n" ); |
356 | goto end; |
357 | } |
358 | if (!link->device->status.enabled) |
359 | acpi_handle_warn(handle, "Disabled and referenced, BIOS bug\n" ); |
360 | |
361 | /* Query _CRS, set link->irq.active */ |
362 | result = acpi_pci_link_get_current(link); |
363 | if (result) { |
364 | goto end; |
365 | } |
366 | |
367 | /* |
368 | * Is current setting not what we set? |
369 | * set link->irq.active |
370 | */ |
371 | if (link->irq.active != irq) { |
372 | /* |
373 | * policy: when _CRS doesn't return what we just _SRS |
374 | * assume _SRS worked and override _CRS value. |
375 | */ |
376 | acpi_handle_warn(handle, "BIOS reported IRQ %d, using IRQ %d\n" , |
377 | link->irq.active, irq); |
378 | link->irq.active = irq; |
379 | } |
380 | |
381 | acpi_handle_debug(handle, "Set IRQ %d\n" , link->irq.active); |
382 | |
383 | end: |
384 | kfree(objp: resource); |
385 | return result; |
386 | } |
387 | |
388 | /* -------------------------------------------------------------------------- |
389 | PCI Link IRQ Management |
390 | -------------------------------------------------------------------------- */ |
391 | |
392 | /* |
393 | * "acpi_irq_balance" (default in APIC mode) enables ACPI to use PIC Interrupt |
394 | * Link Devices to move the PIRQs around to minimize sharing. |
395 | * |
396 | * "acpi_irq_nobalance" (default in PIC mode) tells ACPI not to move any PIC IRQs |
397 | * that the BIOS has already set to active. This is necessary because |
398 | * ACPI has no automatic means of knowing what ISA IRQs are used. Note that |
399 | * if the BIOS doesn't set a Link Device active, ACPI needs to program it |
400 | * even if acpi_irq_nobalance is set. |
401 | * |
402 | * A tables of penalties avoids directing PCI interrupts to well known |
403 | * ISA IRQs. Boot params are available to over-ride the default table: |
404 | * |
405 | * List interrupts that are free for PCI use. |
406 | * acpi_irq_pci=n[,m] |
407 | * |
408 | * List interrupts that should not be used for PCI: |
409 | * acpi_irq_isa=n[,m] |
410 | * |
411 | * Note that PCI IRQ routers have a list of possible IRQs, |
412 | * which may not include the IRQs this table says are available. |
413 | * |
414 | * Since this heuristic can't tell the difference between a link |
415 | * that no device will attach to, vs. a link which may be shared |
416 | * by multiple active devices -- it is not optimal. |
417 | * |
418 | * If interrupt performance is that important, get an IO-APIC system |
419 | * with a pin dedicated to each device. Or for that matter, an MSI |
420 | * enabled system. |
421 | */ |
422 | |
423 | #define ACPI_MAX_ISA_IRQS 16 |
424 | |
425 | #define PIRQ_PENALTY_PCI_POSSIBLE (16*16) |
426 | #define PIRQ_PENALTY_PCI_USING (16*16*16) |
427 | #define PIRQ_PENALTY_ISA_TYPICAL (16*16*16*16) |
428 | #define PIRQ_PENALTY_ISA_USED (16*16*16*16*16) |
429 | #define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16) |
430 | |
431 | static int acpi_isa_irq_penalty[ACPI_MAX_ISA_IRQS] = { |
432 | PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */ |
433 | PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */ |
434 | PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */ |
435 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ3 serial */ |
436 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ4 serial */ |
437 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ5 sometimes SoundBlaster */ |
438 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ6 */ |
439 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ7 parallel, spurious */ |
440 | PIRQ_PENALTY_ISA_TYPICAL, /* IRQ8 rtc, sometimes */ |
441 | 0, /* IRQ9 PCI, often acpi */ |
442 | 0, /* IRQ10 PCI */ |
443 | 0, /* IRQ11 PCI */ |
444 | PIRQ_PENALTY_ISA_USED, /* IRQ12 mouse */ |
445 | PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */ |
446 | PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */ |
447 | PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */ |
448 | /* >IRQ15 */ |
449 | }; |
450 | |
451 | static int acpi_irq_pci_sharing_penalty(int irq) |
452 | { |
453 | struct acpi_pci_link *link; |
454 | int penalty = 0; |
455 | int i; |
456 | |
457 | list_for_each_entry(link, &acpi_link_list, list) { |
458 | /* |
459 | * If a link is active, penalize its IRQ heavily |
460 | * so we try to choose a different IRQ. |
461 | */ |
462 | if (link->irq.active && link->irq.active == irq) |
463 | penalty += PIRQ_PENALTY_PCI_USING; |
464 | |
465 | /* |
466 | * penalize the IRQs PCI might use, but not as severely. |
467 | */ |
468 | for (i = 0; i < link->irq.possible_count; i++) |
469 | if (link->irq.possible[i] == irq) |
470 | penalty += PIRQ_PENALTY_PCI_POSSIBLE / |
471 | link->irq.possible_count; |
472 | } |
473 | |
474 | return penalty; |
475 | } |
476 | |
477 | static int acpi_irq_get_penalty(int irq) |
478 | { |
479 | int penalty = 0; |
480 | |
481 | if (irq == sci_irq) |
482 | penalty += sci_penalty; |
483 | |
484 | if (irq < ACPI_MAX_ISA_IRQS) |
485 | return penalty + acpi_isa_irq_penalty[irq]; |
486 | |
487 | return penalty + acpi_irq_pci_sharing_penalty(irq); |
488 | } |
489 | |
490 | int __init acpi_irq_penalty_init(void) |
491 | { |
492 | struct acpi_pci_link *link; |
493 | int i; |
494 | |
495 | /* |
496 | * Update penalties to facilitate IRQ balancing. |
497 | */ |
498 | list_for_each_entry(link, &acpi_link_list, list) { |
499 | |
500 | /* |
501 | * reflect the possible and active irqs in the penalty table -- |
502 | * useful for breaking ties. |
503 | */ |
504 | if (link->irq.possible_count) { |
505 | int penalty = |
506 | PIRQ_PENALTY_PCI_POSSIBLE / |
507 | link->irq.possible_count; |
508 | |
509 | for (i = 0; i < link->irq.possible_count; i++) { |
510 | if (link->irq.possible[i] < ACPI_MAX_ISA_IRQS) |
511 | acpi_isa_irq_penalty[link->irq. |
512 | possible[i]] += |
513 | penalty; |
514 | } |
515 | |
516 | } else if (link->irq.active && |
517 | (link->irq.active < ACPI_MAX_ISA_IRQS)) { |
518 | acpi_isa_irq_penalty[link->irq.active] += |
519 | PIRQ_PENALTY_PCI_POSSIBLE; |
520 | } |
521 | } |
522 | |
523 | return 0; |
524 | } |
525 | |
526 | static int acpi_irq_balance = -1; /* 0: static, 1: balance */ |
527 | |
528 | static int acpi_pci_link_allocate(struct acpi_pci_link *link) |
529 | { |
530 | acpi_handle handle = link->device->handle; |
531 | int irq; |
532 | int i; |
533 | |
534 | if (link->irq.initialized) { |
535 | if (link->refcnt == 0) |
536 | /* This means the link is disabled but initialized */ |
537 | acpi_pci_link_set(link, irq: link->irq.active); |
538 | return 0; |
539 | } |
540 | |
541 | /* |
542 | * search for active IRQ in list of possible IRQs. |
543 | */ |
544 | for (i = 0; i < link->irq.possible_count; ++i) { |
545 | if (link->irq.active == link->irq.possible[i]) |
546 | break; |
547 | } |
548 | /* |
549 | * forget active IRQ that is not in possible list |
550 | */ |
551 | if (i == link->irq.possible_count) { |
552 | if (acpi_strict) |
553 | acpi_handle_warn(handle, "_CRS %d not found in _PRS\n" , |
554 | link->irq.active); |
555 | link->irq.active = 0; |
556 | } |
557 | |
558 | /* |
559 | * if active found, use it; else pick entry from end of possible list. |
560 | */ |
561 | if (link->irq.active) |
562 | irq = link->irq.active; |
563 | else |
564 | irq = link->irq.possible[link->irq.possible_count - 1]; |
565 | |
566 | if (acpi_irq_balance || !link->irq.active) { |
567 | /* |
568 | * Select the best IRQ. This is done in reverse to promote |
569 | * the use of IRQs 9, 10, 11, and >15. |
570 | */ |
571 | for (i = (link->irq.possible_count - 1); i >= 0; i--) { |
572 | if (acpi_irq_get_penalty(irq) > |
573 | acpi_irq_get_penalty(irq: link->irq.possible[i])) |
574 | irq = link->irq.possible[i]; |
575 | } |
576 | } |
577 | if (acpi_irq_get_penalty(irq) >= PIRQ_PENALTY_ISA_ALWAYS) { |
578 | acpi_handle_err(handle, |
579 | "No IRQ available. Try pci=noacpi or acpi=off\n" ); |
580 | return -ENODEV; |
581 | } |
582 | |
583 | /* Attempt to enable the link device at this IRQ. */ |
584 | if (acpi_pci_link_set(link, irq)) { |
585 | acpi_handle_err(handle, |
586 | "Unable to set IRQ. Try pci=noacpi or acpi=off\n" ); |
587 | return -ENODEV; |
588 | } else { |
589 | if (link->irq.active < ACPI_MAX_ISA_IRQS) |
590 | acpi_isa_irq_penalty[link->irq.active] += |
591 | PIRQ_PENALTY_PCI_USING; |
592 | |
593 | acpi_handle_info(handle, "Enabled at IRQ %d\n" , |
594 | link->irq.active); |
595 | } |
596 | |
597 | link->irq.initialized = 1; |
598 | return 0; |
599 | } |
600 | |
601 | /* |
602 | * acpi_pci_link_allocate_irq |
603 | * success: return IRQ >= 0 |
604 | * failure: return -1 |
605 | */ |
606 | int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering, |
607 | int *polarity, char **name) |
608 | { |
609 | struct acpi_device *device = acpi_fetch_acpi_dev(handle); |
610 | struct acpi_pci_link *link; |
611 | |
612 | if (!device) { |
613 | acpi_handle_err(handle, "Invalid link device\n" ); |
614 | return -1; |
615 | } |
616 | |
617 | link = acpi_driver_data(d: device); |
618 | if (!link) { |
619 | acpi_handle_err(handle, "Invalid link context\n" ); |
620 | return -1; |
621 | } |
622 | |
623 | /* TBD: Support multiple index (IRQ) entries per Link Device */ |
624 | if (index) { |
625 | acpi_handle_err(handle, "Invalid index %d\n" , index); |
626 | return -1; |
627 | } |
628 | |
629 | mutex_lock(&acpi_link_lock); |
630 | if (acpi_pci_link_allocate(link)) { |
631 | mutex_unlock(lock: &acpi_link_lock); |
632 | return -1; |
633 | } |
634 | |
635 | if (!link->irq.active) { |
636 | mutex_unlock(lock: &acpi_link_lock); |
637 | acpi_handle_err(handle, "Link active IRQ is 0!\n" ); |
638 | return -1; |
639 | } |
640 | link->refcnt++; |
641 | mutex_unlock(lock: &acpi_link_lock); |
642 | |
643 | if (triggering) |
644 | *triggering = link->irq.triggering; |
645 | if (polarity) |
646 | *polarity = link->irq.polarity; |
647 | if (name) |
648 | *name = acpi_device_bid(link->device); |
649 | acpi_handle_debug(handle, "Link is referenced\n" ); |
650 | return link->irq.active; |
651 | } |
652 | |
653 | /* |
654 | * We don't change link's irq information here. After it is reenabled, we |
655 | * continue use the info |
656 | */ |
657 | int acpi_pci_link_free_irq(acpi_handle handle) |
658 | { |
659 | struct acpi_device *device = acpi_fetch_acpi_dev(handle); |
660 | struct acpi_pci_link *link; |
661 | |
662 | if (!device) { |
663 | acpi_handle_err(handle, "Invalid link device\n" ); |
664 | return -1; |
665 | } |
666 | |
667 | link = acpi_driver_data(d: device); |
668 | if (!link) { |
669 | acpi_handle_err(handle, "Invalid link context\n" ); |
670 | return -1; |
671 | } |
672 | |
673 | mutex_lock(&acpi_link_lock); |
674 | if (!link->irq.initialized) { |
675 | mutex_unlock(lock: &acpi_link_lock); |
676 | acpi_handle_err(handle, "Link isn't initialized\n" ); |
677 | return -1; |
678 | } |
679 | #ifdef FUTURE_USE |
680 | /* |
681 | * The Link reference count allows us to _DISable an unused link |
682 | * and suspend time, and set it again on resume. |
683 | * However, 2.6.12 still has irq_router.resume |
684 | * which blindly restores the link state. |
685 | * So we disable the reference count method |
686 | * to prevent duplicate acpi_pci_link_set() |
687 | * which would harm some systems |
688 | */ |
689 | link->refcnt--; |
690 | #endif |
691 | acpi_handle_debug(handle, "Link is dereferenced\n" ); |
692 | |
693 | if (link->refcnt == 0) |
694 | acpi_evaluate_object(object: link->device->handle, pathname: "_DIS" , NULL, NULL); |
695 | |
696 | mutex_unlock(lock: &acpi_link_lock); |
697 | return link->irq.active; |
698 | } |
699 | |
700 | /* -------------------------------------------------------------------------- |
701 | Driver Interface |
702 | -------------------------------------------------------------------------- */ |
703 | |
704 | static int acpi_pci_link_add(struct acpi_device *device, |
705 | const struct acpi_device_id *not_used) |
706 | { |
707 | acpi_handle handle = device->handle; |
708 | struct acpi_pci_link *link; |
709 | int result; |
710 | int i; |
711 | |
712 | link = kzalloc(size: sizeof(struct acpi_pci_link), GFP_KERNEL); |
713 | if (!link) |
714 | return -ENOMEM; |
715 | |
716 | link->device = device; |
717 | strcpy(acpi_device_name(device), ACPI_PCI_LINK_DEVICE_NAME); |
718 | strcpy(acpi_device_class(device), ACPI_PCI_LINK_CLASS); |
719 | device->driver_data = link; |
720 | |
721 | mutex_lock(&acpi_link_lock); |
722 | result = acpi_pci_link_get_possible(link); |
723 | if (result) |
724 | goto end; |
725 | |
726 | /* query and set link->irq.active */ |
727 | acpi_pci_link_get_current(link); |
728 | |
729 | pr_info("Interrupt link %s configured for IRQ %d\n" , |
730 | acpi_device_bid(device), link->irq.active); |
731 | |
732 | for (i = 0; i < link->irq.possible_count; i++) { |
733 | if (link->irq.active != link->irq.possible[i]) |
734 | acpi_handle_debug(handle, "Possible IRQ %d\n" , |
735 | link->irq.possible[i]); |
736 | } |
737 | |
738 | if (!link->device->status.enabled) |
739 | pr_info("Interrupt link %s disabled\n" , acpi_device_bid(device)); |
740 | |
741 | list_add_tail(new: &link->list, head: &acpi_link_list); |
742 | |
743 | end: |
744 | /* disable all links -- to be activated on use */ |
745 | acpi_evaluate_object(object: handle, pathname: "_DIS" , NULL, NULL); |
746 | mutex_unlock(lock: &acpi_link_lock); |
747 | |
748 | if (result) |
749 | kfree(objp: link); |
750 | |
751 | return result < 0 ? result : 1; |
752 | } |
753 | |
754 | static int acpi_pci_link_resume(struct acpi_pci_link *link) |
755 | { |
756 | if (link->refcnt && link->irq.active && link->irq.initialized) |
757 | return (acpi_pci_link_set(link, irq: link->irq.active)); |
758 | |
759 | return 0; |
760 | } |
761 | |
762 | static void irqrouter_resume(void) |
763 | { |
764 | struct acpi_pci_link *link; |
765 | |
766 | list_for_each_entry(link, &acpi_link_list, list) { |
767 | acpi_pci_link_resume(link); |
768 | } |
769 | } |
770 | |
771 | static void acpi_pci_link_remove(struct acpi_device *device) |
772 | { |
773 | struct acpi_pci_link *link; |
774 | |
775 | link = acpi_driver_data(d: device); |
776 | |
777 | mutex_lock(&acpi_link_lock); |
778 | list_del(entry: &link->list); |
779 | mutex_unlock(lock: &acpi_link_lock); |
780 | |
781 | kfree(objp: link); |
782 | } |
783 | |
784 | /* |
785 | * modify acpi_isa_irq_penalty[] from cmdline |
786 | */ |
787 | static int __init acpi_irq_penalty_update(char *str, int used) |
788 | { |
789 | int i; |
790 | |
791 | for (i = 0; i < 16; i++) { |
792 | int retval; |
793 | int irq; |
794 | int new_penalty; |
795 | |
796 | retval = get_option(str: &str, pint: &irq); |
797 | |
798 | if (!retval) |
799 | break; /* no number found */ |
800 | |
801 | /* see if this is a ISA IRQ */ |
802 | if ((irq < 0) || (irq >= ACPI_MAX_ISA_IRQS)) |
803 | continue; |
804 | |
805 | if (used) |
806 | new_penalty = acpi_isa_irq_penalty[irq] + |
807 | PIRQ_PENALTY_ISA_USED; |
808 | else |
809 | new_penalty = 0; |
810 | |
811 | acpi_isa_irq_penalty[irq] = new_penalty; |
812 | if (retval != 2) /* no next number */ |
813 | break; |
814 | } |
815 | return 1; |
816 | } |
817 | |
818 | /* |
819 | * We'd like PNP to call this routine for the |
820 | * single ISA_USED value for each legacy device. |
821 | * But instead it calls us with each POSSIBLE setting. |
822 | * There is no ISA_POSSIBLE weight, so we simply use |
823 | * the (small) PCI_USING penalty. |
824 | */ |
825 | void acpi_penalize_isa_irq(int irq, int active) |
826 | { |
827 | if ((irq >= 0) && (irq < ARRAY_SIZE(acpi_isa_irq_penalty))) |
828 | acpi_isa_irq_penalty[irq] += |
829 | (active ? PIRQ_PENALTY_ISA_USED : PIRQ_PENALTY_PCI_USING); |
830 | } |
831 | |
832 | bool acpi_isa_irq_available(int irq) |
833 | { |
834 | return irq >= 0 && (irq >= ARRAY_SIZE(acpi_isa_irq_penalty) || |
835 | acpi_irq_get_penalty(irq) < PIRQ_PENALTY_ISA_ALWAYS); |
836 | } |
837 | |
838 | void acpi_penalize_sci_irq(int irq, int trigger, int polarity) |
839 | { |
840 | sci_irq = irq; |
841 | |
842 | if (trigger == ACPI_MADT_TRIGGER_LEVEL && |
843 | polarity == ACPI_MADT_POLARITY_ACTIVE_LOW) |
844 | sci_penalty = PIRQ_PENALTY_PCI_USING; |
845 | else |
846 | sci_penalty = PIRQ_PENALTY_ISA_ALWAYS; |
847 | } |
848 | |
849 | /* |
850 | * Over-ride default table to reserve additional IRQs for use by ISA |
851 | * e.g. acpi_irq_isa=5 |
852 | * Useful for telling ACPI how not to interfere with your ISA sound card. |
853 | */ |
854 | static int __init acpi_irq_isa(char *str) |
855 | { |
856 | return acpi_irq_penalty_update(str, used: 1); |
857 | } |
858 | |
859 | __setup("acpi_irq_isa=" , acpi_irq_isa); |
860 | |
861 | /* |
862 | * Over-ride default table to free additional IRQs for use by PCI |
863 | * e.g. acpi_irq_pci=7,15 |
864 | * Used for acpi_irq_balance to free up IRQs to reduce PCI IRQ sharing. |
865 | */ |
866 | static int __init acpi_irq_pci(char *str) |
867 | { |
868 | return acpi_irq_penalty_update(str, used: 0); |
869 | } |
870 | |
871 | __setup("acpi_irq_pci=" , acpi_irq_pci); |
872 | |
873 | static int __init acpi_irq_nobalance_set(char *str) |
874 | { |
875 | acpi_irq_balance = 0; |
876 | return 1; |
877 | } |
878 | |
879 | __setup("acpi_irq_nobalance" , acpi_irq_nobalance_set); |
880 | |
881 | static int __init acpi_irq_balance_set(char *str) |
882 | { |
883 | acpi_irq_balance = 1; |
884 | return 1; |
885 | } |
886 | |
887 | __setup("acpi_irq_balance" , acpi_irq_balance_set); |
888 | |
889 | static struct syscore_ops irqrouter_syscore_ops = { |
890 | .resume = irqrouter_resume, |
891 | }; |
892 | |
893 | void __init acpi_pci_link_init(void) |
894 | { |
895 | if (acpi_noirq) |
896 | return; |
897 | |
898 | if (acpi_irq_balance == -1) { |
899 | /* no command line switch: enable balancing in IOAPIC mode */ |
900 | if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC) |
901 | acpi_irq_balance = 1; |
902 | else |
903 | acpi_irq_balance = 0; |
904 | } |
905 | register_syscore_ops(ops: &irqrouter_syscore_ops); |
906 | acpi_scan_add_handler(handler: &pci_link_handler); |
907 | } |
908 | |