xref: /openbmc/linux/drivers/pci/hotplug/cpci_hotplug_pci.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * CompactPCI Hot Plug Driver PCI functions
3  *
4  * Copyright (C) 2002 by SOMA Networks, Inc.
5  *
6  * All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or (at
11  * your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Send feedback to <scottm@somanetworks.com>
24  */
25 
26 #include <linux/config.h>
27 #include <linux/module.h>
28 #include <linux/kernel.h>
29 #include <linux/pci.h>
30 #include <linux/proc_fs.h>
31 #include "../pci.h"
32 #include "pci_hotplug.h"
33 #include "cpci_hotplug.h"
34 
35 #if !defined(MODULE)
36 #define MY_NAME	"cpci_hotplug"
37 #else
38 #define MY_NAME	THIS_MODULE->name
39 #endif
40 
41 extern int cpci_debug;
42 
43 #define dbg(format, arg...)					\
44 	do {							\
45 		if(cpci_debug)					\
46 			printk (KERN_DEBUG "%s: " format "\n",	\
47 				MY_NAME , ## arg); 		\
48 	} while(0)
49 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg)
50 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg)
51 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg)
52 
53 #define ROUND_UP(x, a)		(((x) + (a) - 1) & ~((a) - 1))
54 
55 
56 u8 cpci_get_attention_status(struct slot* slot)
57 {
58 	int hs_cap;
59 	u16 hs_csr;
60 
61 	hs_cap = pci_bus_find_capability(slot->bus,
62 					 slot->devfn,
63 					 PCI_CAP_ID_CHSWP);
64 	if(!hs_cap) {
65 		return 0;
66 	}
67 
68 	if(pci_bus_read_config_word(slot->bus,
69 				     slot->devfn,
70 				     hs_cap + 2,
71 				     &hs_csr)) {
72 		return 0;
73 	}
74 	return hs_csr & 0x0008 ? 1 : 0;
75 }
76 
77 int cpci_set_attention_status(struct slot* slot, int status)
78 {
79 	int hs_cap;
80 	u16 hs_csr;
81 
82 	hs_cap = pci_bus_find_capability(slot->bus,
83 					 slot->devfn,
84 					 PCI_CAP_ID_CHSWP);
85 	if(!hs_cap) {
86 		return 0;
87 	}
88 
89 	if(pci_bus_read_config_word(slot->bus,
90 				     slot->devfn,
91 				     hs_cap + 2,
92 				     &hs_csr)) {
93 		return 0;
94 	}
95 	if(status) {
96 		hs_csr |= HS_CSR_LOO;
97 	} else {
98 		hs_csr &= ~HS_CSR_LOO;
99 	}
100 	if(pci_bus_write_config_word(slot->bus,
101 				      slot->devfn,
102 				      hs_cap + 2,
103 				      hs_csr)) {
104 		return 0;
105 	}
106 	return 1;
107 }
108 
109 u16 cpci_get_hs_csr(struct slot* slot)
110 {
111 	int hs_cap;
112 	u16 hs_csr;
113 
114 	hs_cap = pci_bus_find_capability(slot->bus,
115 					 slot->devfn,
116 					 PCI_CAP_ID_CHSWP);
117 	if(!hs_cap) {
118 		return 0xFFFF;
119 	}
120 
121 	if(pci_bus_read_config_word(slot->bus,
122 				     slot->devfn,
123 				     hs_cap + 2,
124 				     &hs_csr)) {
125 		return 0xFFFF;
126 	}
127 	return hs_csr;
128 }
129 
130 #if 0
131 u16 cpci_set_hs_csr(struct slot* slot, u16 hs_csr)
132 {
133 	int hs_cap;
134 	u16 new_hs_csr;
135 
136 	hs_cap = pci_bus_find_capability(slot->bus,
137 					 slot->devfn,
138 					 PCI_CAP_ID_CHSWP);
139 	if(!hs_cap) {
140 		return 0xFFFF;
141 	}
142 
143 	/* Write out the new value */
144 	if(pci_bus_write_config_word(slot->bus,
145 				      slot->devfn,
146 				      hs_cap + 2,
147 				      hs_csr)) {
148 		return 0xFFFF;
149 	}
150 
151 	/* Read back what we just wrote out */
152 	if(pci_bus_read_config_word(slot->bus,
153 				     slot->devfn,
154 				     hs_cap + 2,
155 				     &new_hs_csr)) {
156 		return 0xFFFF;
157 	}
158 	return new_hs_csr;
159 }
160 #endif
161 
162 int cpci_check_and_clear_ins(struct slot* slot)
163 {
164 	int hs_cap;
165 	u16 hs_csr;
166 	int ins = 0;
167 
168 	hs_cap = pci_bus_find_capability(slot->bus,
169 					 slot->devfn,
170 					 PCI_CAP_ID_CHSWP);
171 	if(!hs_cap) {
172 		return 0;
173 	}
174 	if(pci_bus_read_config_word(slot->bus,
175 				     slot->devfn,
176 				     hs_cap + 2,
177 				     &hs_csr)) {
178 		return 0;
179 	}
180 	if(hs_csr & HS_CSR_INS) {
181 		/* Clear INS (by setting it) */
182 		if(pci_bus_write_config_word(slot->bus,
183 					      slot->devfn,
184 					      hs_cap + 2,
185 					      hs_csr)) {
186 			ins = 0;
187 		}
188 		ins = 1;
189 	}
190 	return ins;
191 }
192 
193 int cpci_check_ext(struct slot* slot)
194 {
195 	int hs_cap;
196 	u16 hs_csr;
197 	int ext = 0;
198 
199 	hs_cap = pci_bus_find_capability(slot->bus,
200 					 slot->devfn,
201 					 PCI_CAP_ID_CHSWP);
202 	if(!hs_cap) {
203 		return 0;
204 	}
205 	if(pci_bus_read_config_word(slot->bus,
206 				     slot->devfn,
207 				     hs_cap + 2,
208 				     &hs_csr)) {
209 		return 0;
210 	}
211 	if(hs_csr & HS_CSR_EXT) {
212 		ext = 1;
213 	}
214 	return ext;
215 }
216 
217 int cpci_clear_ext(struct slot* slot)
218 {
219 	int hs_cap;
220 	u16 hs_csr;
221 
222 	hs_cap = pci_bus_find_capability(slot->bus,
223 					 slot->devfn,
224 					 PCI_CAP_ID_CHSWP);
225 	if(!hs_cap) {
226 		return -ENODEV;
227 	}
228 	if(pci_bus_read_config_word(slot->bus,
229 				     slot->devfn,
230 				     hs_cap + 2,
231 				     &hs_csr)) {
232 		return -ENODEV;
233 	}
234 	if(hs_csr & HS_CSR_EXT) {
235 		/* Clear EXT (by setting it) */
236 		if(pci_bus_write_config_word(slot->bus,
237 					      slot->devfn,
238 					      hs_cap + 2,
239 					      hs_csr)) {
240 			return -ENODEV;
241 		}
242 	}
243 	return 0;
244 }
245 
246 int cpci_led_on(struct slot* slot)
247 {
248 	int hs_cap;
249 	u16 hs_csr;
250 
251 	hs_cap = pci_bus_find_capability(slot->bus,
252 					 slot->devfn,
253 					 PCI_CAP_ID_CHSWP);
254 	if(!hs_cap) {
255 		return -ENODEV;
256 	}
257 	if(pci_bus_read_config_word(slot->bus,
258 				     slot->devfn,
259 				     hs_cap + 2,
260 				     &hs_csr)) {
261 		return -ENODEV;
262 	}
263 	if((hs_csr & HS_CSR_LOO) != HS_CSR_LOO) {
264 		/* Set LOO */
265 		hs_csr |= HS_CSR_LOO;
266 		if(pci_bus_write_config_word(slot->bus,
267 					      slot->devfn,
268 					      hs_cap + 2,
269 					      hs_csr)) {
270 			err("Could not set LOO for slot %s",
271 			    slot->hotplug_slot->name);
272 			return -ENODEV;
273 		}
274 	}
275 	return 0;
276 }
277 
278 int cpci_led_off(struct slot* slot)
279 {
280 	int hs_cap;
281 	u16 hs_csr;
282 
283 	hs_cap = pci_bus_find_capability(slot->bus,
284 					 slot->devfn,
285 					 PCI_CAP_ID_CHSWP);
286 	if(!hs_cap) {
287 		return -ENODEV;
288 	}
289 	if(pci_bus_read_config_word(slot->bus,
290 				     slot->devfn,
291 				     hs_cap + 2,
292 				     &hs_csr)) {
293 		return -ENODEV;
294 	}
295 	if(hs_csr & HS_CSR_LOO) {
296 		/* Clear LOO */
297 		hs_csr &= ~HS_CSR_LOO;
298 		if(pci_bus_write_config_word(slot->bus,
299 					      slot->devfn,
300 					      hs_cap + 2,
301 					      hs_csr)) {
302 			err("Could not clear LOO for slot %s",
303 			    slot->hotplug_slot->name);
304 			return -ENODEV;
305 		}
306 	}
307 	return 0;
308 }
309 
310 
311 /*
312  * Device configuration functions
313  */
314 
315 static int cpci_configure_dev(struct pci_bus *bus, struct pci_dev *dev)
316 {
317 	u8 irq_pin;
318 	int r;
319 
320 	dbg("%s - enter", __FUNCTION__);
321 
322 	/* NOTE: device already setup from prior scan */
323 
324 	/* FIXME: How would we know if we need to enable the expansion ROM? */
325 	pci_write_config_word(dev, PCI_ROM_ADDRESS, 0x00L);
326 
327 	/* Assign resources */
328 	dbg("assigning resources for %02x:%02x.%x",
329 	    dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
330 	for (r = 0; r < 6; r++) {
331 		struct resource *res = dev->resource + r;
332 		if(res->flags)
333 			pci_assign_resource(dev, r);
334 	}
335 	dbg("finished assigning resources for %02x:%02x.%x",
336 	    dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
337 
338 	/* Does this function have an interrupt at all? */
339 	dbg("checking for function interrupt");
340 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq_pin);
341 	if(irq_pin) {
342 		dbg("function uses interrupt pin %d", irq_pin);
343 	}
344 
345 	/*
346 	 * Need to explicitly set irq field to 0 so that it'll get assigned
347 	 * by the pcibios platform dependent code called by pci_enable_device.
348 	 */
349 	dev->irq = 0;
350 
351 	dbg("enabling device");
352 	pci_enable_device(dev);	/* XXX check return */
353 	dbg("now dev->irq = %d", dev->irq);
354 	if(irq_pin && dev->irq) {
355 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
356 	}
357 
358 	/* Can't use pci_insert_device at the moment, do it manually for now */
359 	pci_proc_attach_device(dev);
360 	dbg("notifying drivers");
361 	//pci_announce_device_to_drivers(dev);
362 	dbg("%s - exit", __FUNCTION__);
363 	return 0;
364 }
365 
366 static int cpci_configure_bridge(struct pci_bus* bus, struct pci_dev* dev)
367 {
368 	int rc;
369 	struct pci_bus* child;
370 	struct resource* r;
371 	u8 max, n;
372 	u16 command;
373 
374 	dbg("%s - enter", __FUNCTION__);
375 
376 	/* Do basic bridge initialization */
377 	rc = pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0x40);
378 	if(rc) {
379 		printk(KERN_ERR "%s - write of PCI_LATENCY_TIMER failed\n", __FUNCTION__);
380 	}
381 	rc = pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER, 0x40);
382 	if(rc) {
383 		printk(KERN_ERR "%s - write of PCI_SEC_LATENCY_TIMER failed\n", __FUNCTION__);
384 	}
385 	rc = pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, L1_CACHE_BYTES / 4);
386 	if(rc) {
387 		printk(KERN_ERR "%s - write of PCI_CACHE_LINE_SIZE failed\n", __FUNCTION__);
388 	}
389 
390 	/*
391 	 * Set parent bridge's subordinate field so that configuration space
392 	 * access will work in pci_scan_bridge and friends.
393 	 */
394 	max = pci_max_busnr();
395 	bus->subordinate = max + 1;
396 	pci_write_config_byte(bus->self, PCI_SUBORDINATE_BUS, max + 1);
397 
398 	/* Scan behind bridge */
399 	n = pci_scan_bridge(bus, dev, max, 2);
400 	child = pci_find_bus(0, max + 1);
401 	if (!child)
402 		return -ENODEV;
403 	pci_proc_attach_bus(child);
404 
405 	/*
406 	 * Update parent bridge's subordinate field if there were more bridges
407 	 * behind the bridge that was scanned.
408 	 */
409 	if(n > max) {
410 		bus->subordinate = n;
411 		pci_write_config_byte(bus->self, PCI_SUBORDINATE_BUS, n);
412 	}
413 
414 	/*
415 	 * Update the bridge resources of the bridge to accommodate devices
416 	 * behind it.
417 	 */
418 	pci_bus_size_bridges(child);
419 	pci_bus_assign_resources(child);
420 
421 	/* Enable resource mapping via command register */
422 	command = PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE | PCI_COMMAND_PARITY | PCI_COMMAND_SERR;
423 	r = child->resource[0];
424 	if(r && r->start) {
425 		command |= PCI_COMMAND_IO;
426 	}
427 	r = child->resource[1];
428 	if(r && r->start) {
429 		command |= PCI_COMMAND_MEMORY;
430 	}
431 	r = child->resource[2];
432 	if(r && r->start) {
433 		command |= PCI_COMMAND_MEMORY;
434 	}
435 	rc = pci_write_config_word(dev, PCI_COMMAND, command);
436 	if(rc) {
437 		err("Error setting command register");
438 		return rc;
439 	}
440 
441 	/* Set bridge control register */
442 	command = PCI_BRIDGE_CTL_PARITY | PCI_BRIDGE_CTL_SERR | PCI_BRIDGE_CTL_NO_ISA;
443 	rc = pci_write_config_word(dev, PCI_BRIDGE_CONTROL, command);
444 	if(rc) {
445 		err("Error setting bridge control register");
446 		return rc;
447 	}
448 	dbg("%s - exit", __FUNCTION__);
449 	return 0;
450 }
451 
452 static int configure_visit_pci_dev(struct pci_dev_wrapped *wrapped_dev,
453 				   struct pci_bus_wrapped *wrapped_bus)
454 {
455 	int rc;
456 	struct pci_dev *dev = wrapped_dev->dev;
457 	struct pci_bus *bus = wrapped_bus->bus;
458 	struct slot* slot;
459 
460 	dbg("%s - enter", __FUNCTION__);
461 
462 	/*
463 	 * We need to fix up the hotplug representation with the Linux
464 	 * representation.
465 	 */
466 	if(wrapped_dev->data) {
467 		slot = (struct slot*) wrapped_dev->data;
468 		slot->dev = dev;
469 	}
470 
471 	/* If it's a bridge, scan behind it for devices */
472 	if(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
473 		rc = cpci_configure_bridge(bus, dev);
474 		if(rc)
475 			return rc;
476 	}
477 
478 	/* Actually configure device */
479 	if(dev) {
480 		rc = cpci_configure_dev(bus, dev);
481 		if(rc)
482 			return rc;
483 	}
484 	dbg("%s - exit", __FUNCTION__);
485 	return 0;
486 }
487 
488 static int unconfigure_visit_pci_dev_phase2(struct pci_dev_wrapped *wrapped_dev,
489 					    struct pci_bus_wrapped *wrapped_bus)
490 {
491 	struct pci_dev *dev = wrapped_dev->dev;
492 	struct slot* slot;
493 
494 	dbg("%s - enter", __FUNCTION__);
495 	if(!dev)
496 		return -ENODEV;
497 
498 	/* Remove the Linux representation */
499 	if(pci_remove_device_safe(dev)) {
500 		err("Could not remove device\n");
501 		return -1;
502 	}
503 
504 	/*
505 	 * Now remove the hotplug representation.
506 	 */
507 	if(wrapped_dev->data) {
508 		slot = (struct slot*) wrapped_dev->data;
509 		slot->dev = NULL;
510 	} else {
511 		dbg("No hotplug representation for %02x:%02x.%x",
512 		    dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
513 	}
514 	dbg("%s - exit", __FUNCTION__);
515 	return 0;
516 }
517 
518 static int unconfigure_visit_pci_bus_phase2(struct pci_bus_wrapped *wrapped_bus,
519 					    struct pci_dev_wrapped *wrapped_dev)
520 {
521 	struct pci_bus *bus = wrapped_bus->bus;
522 	struct pci_bus *parent = bus->self->bus;
523 
524 	dbg("%s - enter", __FUNCTION__);
525 
526 	/* The cleanup code for proc entries regarding buses should be in the kernel... */
527 	if(bus->procdir)
528 		dbg("detach_pci_bus %s", bus->procdir->name);
529 	pci_proc_detach_bus(bus);
530 
531 	/* The cleanup code should live in the kernel... */
532 	bus->self->subordinate = NULL;
533 
534 	/* unlink from parent bus */
535 	list_del(&bus->node);
536 
537 	/* Now, remove */
538 	if(bus)
539 		kfree(bus);
540 
541 	/* Update parent's subordinate field */
542 	if(parent) {
543 		u8 n = pci_bus_max_busnr(parent);
544 		if(n < parent->subordinate) {
545 			parent->subordinate = n;
546 			pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, n);
547 		}
548 	}
549 	dbg("%s - exit", __FUNCTION__);
550 	return 0;
551 }
552 
553 static struct pci_visit configure_functions = {
554 	.visit_pci_dev = configure_visit_pci_dev,
555 };
556 
557 static struct pci_visit unconfigure_functions_phase2 = {
558 	.post_visit_pci_bus = unconfigure_visit_pci_bus_phase2,
559 	.post_visit_pci_dev = unconfigure_visit_pci_dev_phase2
560 };
561 
562 
563 int cpci_configure_slot(struct slot* slot)
564 {
565 	int rc = 0;
566 
567 	dbg("%s - enter", __FUNCTION__);
568 
569 	if(slot->dev == NULL) {
570 		dbg("pci_dev null, finding %02x:%02x:%x",
571 		    slot->bus->number, PCI_SLOT(slot->devfn), PCI_FUNC(slot->devfn));
572 		slot->dev = pci_find_slot(slot->bus->number, slot->devfn);
573 	}
574 
575 	/* Still NULL? Well then scan for it! */
576 	if(slot->dev == NULL) {
577 		int n;
578 		dbg("pci_dev still null");
579 
580 		/*
581 		 * This will generate pci_dev structures for all functions, but
582 		 * we will only call this case when lookup fails.
583 		 */
584 		n = pci_scan_slot(slot->bus, slot->devfn);
585 		dbg("%s: pci_scan_slot returned %d", __FUNCTION__, n);
586 		if(n > 0)
587 			pci_bus_add_devices(slot->bus);
588 		slot->dev = pci_find_slot(slot->bus->number, slot->devfn);
589 		if(slot->dev == NULL) {
590 			err("Could not find PCI device for slot %02x", slot->number);
591 			return 0;
592 		}
593 	}
594 	dbg("slot->dev = %p", slot->dev);
595 	if(slot->dev) {
596 		struct pci_dev *dev;
597 		struct pci_dev_wrapped wrapped_dev;
598 		struct pci_bus_wrapped wrapped_bus;
599 		int i;
600 
601 		memset(&wrapped_dev, 0, sizeof (struct pci_dev_wrapped));
602 		memset(&wrapped_bus, 0, sizeof (struct pci_bus_wrapped));
603 
604 		for (i = 0; i < 8; i++) {
605 			dev = pci_find_slot(slot->bus->number,
606 					    PCI_DEVFN(PCI_SLOT(slot->dev->devfn), i));
607 			if(!dev)
608 				continue;
609 			wrapped_dev.dev = dev;
610 			wrapped_bus.bus = slot->dev->bus;
611 			if(i)
612 				wrapped_dev.data = NULL;
613 			else
614 				wrapped_dev.data = (void*) slot;
615 			rc = pci_visit_dev(&configure_functions, &wrapped_dev, &wrapped_bus);
616 		}
617 	}
618 
619 	dbg("%s - exit, rc = %d", __FUNCTION__, rc);
620 	return rc;
621 }
622 
623 int cpci_unconfigure_slot(struct slot* slot)
624 {
625 	int rc = 0;
626 	int i;
627 	struct pci_dev_wrapped wrapped_dev;
628 	struct pci_bus_wrapped wrapped_bus;
629 	struct pci_dev *dev;
630 
631 	dbg("%s - enter", __FUNCTION__);
632 
633 	if(!slot->dev) {
634 		err("No device for slot %02x\n", slot->number);
635 		return -ENODEV;
636 	}
637 
638 	memset(&wrapped_dev, 0, sizeof (struct pci_dev_wrapped));
639 	memset(&wrapped_bus, 0, sizeof (struct pci_bus_wrapped));
640 
641 	for (i = 0; i < 8; i++) {
642 		dev = pci_find_slot(slot->bus->number,
643 				    PCI_DEVFN(PCI_SLOT(slot->devfn), i));
644 		if(dev) {
645 			wrapped_dev.dev = dev;
646 			wrapped_bus.bus = dev->bus;
647  			if(i)
648  				wrapped_dev.data = NULL;
649  			else
650  				wrapped_dev.data = (void*) slot;
651 			dbg("%s - unconfigure phase 2", __FUNCTION__);
652 			rc = pci_visit_dev(&unconfigure_functions_phase2,
653 					   &wrapped_dev,
654 					   &wrapped_bus);
655 			if(rc)
656 				break;
657 		}
658 	}
659 	dbg("%s - exit, rc = %d", __FUNCTION__, rc);
660 	return rc;
661 }
662