xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_pci.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform.
3  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
4  *
5  * All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or (at
10  * your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15  * NON INFRINGEMENT.  See the GNU General Public License for more
16  * details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  *
22  * Send feedback to <lxie@us.ibm.com>
23  *
24  */
25 #include <linux/pci.h>
26 #include <asm/pci-bridge.h>
27 #include <asm/rtas.h>
28 #include <asm/machdep.h>
29 #include "../pci.h"		/* for pci_add_new_bus */
30 
31 #include "rpaphp.h"
32 
33 struct pci_dev *rpaphp_find_pci_dev(struct device_node *dn)
34 {
35 	struct pci_dev *dev = NULL;
36 	char bus_id[BUS_ID_SIZE];
37 
38 	sprintf(bus_id, "%04x:%02x:%02x.%d", dn->phb->global_number,
39 		dn->busno, PCI_SLOT(dn->devfn), PCI_FUNC(dn->devfn));
40 	for_each_pci_dev(dev) {
41 		if (!strcmp(pci_name(dev), bus_id)) {
42 			break;
43 		}
44 	}
45 	return dev;
46 }
47 
48 EXPORT_SYMBOL_GPL(rpaphp_find_pci_dev);
49 
50 int rpaphp_claim_resource(struct pci_dev *dev, int resource)
51 {
52 	struct resource *res = &dev->resource[resource];
53 	struct resource *root = pci_find_parent_resource(dev, res);
54 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
55 	int err = -EINVAL;
56 
57 	if (root != NULL) {
58 		err = request_resource(root, res);
59 	}
60 
61 	if (err) {
62 		err("PCI: %s region %d of %s %s [%lx:%lx]\n",
63 		    root ? "Address space collision on" :
64 		    "No parent found for",
65 		    resource, dtype, pci_name(dev), res->start, res->end);
66 	}
67 	return err;
68 }
69 
70 EXPORT_SYMBOL_GPL(rpaphp_claim_resource);
71 
72 static struct pci_dev *rpaphp_find_bridge_pdev(struct slot *slot)
73 {
74 	return rpaphp_find_pci_dev(slot->dn);
75 }
76 
77 static int rpaphp_get_sensor_state(struct slot *slot, int *state)
78 {
79 	int rc;
80 	int setlevel;
81 
82 	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
83 
84 	if (rc < 0) {
85 		if (rc == -EFAULT || rc == -EEXIST) {
86 			dbg("%s: slot must be power up to get sensor-state\n",
87 			    __FUNCTION__);
88 
89 			/* some slots have to be powered up
90 			 * before get-sensor will succeed.
91 			 */
92 			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
93 						  &setlevel);
94 			if (rc < 0) {
95 				dbg("%s: power on slot[%s] failed rc=%d.\n",
96 				    __FUNCTION__, slot->name, rc);
97 			} else {
98 				rc = rtas_get_sensor(DR_ENTITY_SENSE,
99 						     slot->index, state);
100 			}
101 		} else if (rc == -ENODEV)
102 			info("%s: slot is unusable\n", __FUNCTION__);
103 		else
104 			err("%s failed to get sensor state\n", __FUNCTION__);
105 	}
106 	return rc;
107 }
108 
109 /**
110  * get_pci_adapter_status - get the status of a slot
111  *
112  * 0-- slot is empty
113  * 1-- adapter is configured
114  * 2-- adapter is not configured
115  * 3-- not valid
116  */
117 int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
118 {
119 	int state, rc;
120  	struct device_node *child_dn;
121  	struct pci_dev *child_dev = NULL;
122 
123 	*value = NOT_VALID;
124 	rc = rpaphp_get_sensor_state(slot, &state);
125 	if (rc)
126 		goto exit;
127 
128  	if ((state == EMPTY) || (slot->type == PHB)) {
129  		dbg("slot is empty\n");
130  		*value = EMPTY;
131  	}
132  	else if (state == PRESENT) {
133 		if (!is_init) {
134 			/* at run-time slot->state can be changed by */
135 			/* config/unconfig adapter */
136 			*value = slot->state;
137 		} else {
138  			child_dn = slot->dn->child;
139  			if (child_dn)
140  				child_dev = rpaphp_find_pci_dev(child_dn);
141 
142  			if (child_dev)
143  				*value = CONFIGURED;
144  			else if (!child_dn)
145 				dbg("%s: %s is not valid OFDT node\n",
146 				    __FUNCTION__, slot->dn->full_name);
147 			else {
148 				err("%s: can't find pdev of adapter in slot[%s]\n",
149 					__FUNCTION__, slot->dn->full_name);
150 				*value = NOT_CONFIGURED;
151 			}
152 		}
153 	}
154 exit:
155 	return rc;
156 }
157 
158 /* Must be called before pci_bus_add_devices */
159 static void
160 rpaphp_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
161 {
162 	struct pci_dev *dev;
163 
164 	list_for_each_entry(dev, &bus->devices, bus_list) {
165 		/*
166 		 * Skip already-present devices (which are on the
167 		 * global device list.)
168 		 */
169 		if (list_empty(&dev->global_list)) {
170 			int i;
171 
172 			/* Need to setup IOMMU tables */
173 			ppc_md.iommu_dev_setup(dev);
174 
175 			if(fix_bus)
176 				pcibios_fixup_device_resources(dev, bus);
177 			pci_read_irq_line(dev);
178 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
179 				struct resource *r = &dev->resource[i];
180 
181 				if (r->parent || !r->start || !r->flags)
182 					continue;
183 				rpaphp_claim_resource(dev, i);
184 			}
185 		}
186 	}
187 }
188 
189 static int rpaphp_pci_config_bridge(struct pci_dev *dev);
190 
191 /*****************************************************************************
192  rpaphp_pci_config_slot() will  configure all devices under the
193  given slot->dn and return the the first pci_dev.
194  *****************************************************************************/
195 static struct pci_dev *
196 rpaphp_pci_config_slot(struct device_node *dn, struct pci_bus *bus)
197 {
198 	struct device_node *eads_first_child = dn->child;
199 	struct pci_dev *dev = NULL;
200 	int num;
201 
202 	dbg("Enter %s: dn=%s bus=%s\n", __FUNCTION__, dn->full_name, bus->name);
203 
204 	if (eads_first_child) {
205 		/* pci_scan_slot should find all children of EADs */
206 		num = pci_scan_slot(bus, PCI_DEVFN(PCI_SLOT(eads_first_child->devfn), 0));
207 		if (num) {
208 			rpaphp_fixup_new_pci_devices(bus, 1);
209 			pci_bus_add_devices(bus);
210 		}
211 		dev = rpaphp_find_pci_dev(eads_first_child);
212 		if (!dev) {
213 			err("No new device found\n");
214 			return NULL;
215 		}
216 		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
217 			rpaphp_pci_config_bridge(dev);
218 	}
219 	return dev;
220 }
221 
222 static int rpaphp_pci_config_bridge(struct pci_dev *dev)
223 {
224 	u8 sec_busno;
225 	struct pci_bus *child_bus;
226 	struct pci_dev *child_dev;
227 
228 	dbg("Enter %s:  BRIDGE dev=%s\n", __FUNCTION__, pci_name(dev));
229 
230 	/* get busno of downstream bus */
231 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
232 
233 	/* add to children of PCI bridge dev->bus */
234 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
235 	if (!child_bus) {
236 		err("%s: could not add second bus\n", __FUNCTION__);
237 		return -EIO;
238 	}
239 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
240 	/* do pci_scan_child_bus */
241 	pci_scan_child_bus(child_bus);
242 
243 	list_for_each_entry(child_dev, &child_bus->devices, bus_list) {
244 		eeh_add_device_late(child_dev);
245 	}
246 
247 	 /* fixup new pci devices without touching bus struct */
248 	rpaphp_fixup_new_pci_devices(child_bus, 0);
249 
250 	/* Make the discovered devices available */
251 	pci_bus_add_devices(child_bus);
252 	return 0;
253 }
254 
255 static void enable_eeh(struct device_node *dn)
256 {
257 	struct device_node *sib;
258 
259 	for (sib = dn->child; sib; sib = sib->sibling)
260 		enable_eeh(sib);
261 	eeh_add_device_early(dn);
262 	return;
263 
264 }
265 
266 static void print_slot_pci_funcs(struct slot *slot)
267 {
268 	struct pci_dev *dev;
269 
270 	if (slot->dev_type == PCI_DEV) {
271 		dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, slot->name);
272 		list_for_each_entry (dev, slot->dev.pci_devs, bus_list)
273 			dbg("\t%s\n", pci_name(dev));
274 	}
275 	return;
276 }
277 
278 static int rpaphp_config_pci_adapter(struct slot *slot)
279 {
280 	struct pci_bus *pci_bus;
281 	struct pci_dev *dev;
282 	int rc = -ENODEV;
283 
284 	dbg("Entry %s: slot[%s]\n", __FUNCTION__, slot->name);
285 
286 	if (slot->bridge) {
287 
288 		pci_bus = slot->bridge->subordinate;
289 		if (!pci_bus) {
290 			err("%s: can't find bus structure\n", __FUNCTION__);
291 			goto exit;
292 		}
293 		enable_eeh(slot->dn);
294 		dev = rpaphp_pci_config_slot(slot->dn, pci_bus);
295 		if (!dev) {
296 			err("%s: can't find any devices.\n", __FUNCTION__);
297 			goto exit;
298 		}
299 		print_slot_pci_funcs(slot);
300 		rc = 0;
301 	} else {
302 		/* slot is not enabled */
303 		err("slot doesn't have pci_dev structure\n");
304 	}
305 exit:
306 	dbg("Exit %s:  rc=%d\n", __FUNCTION__, rc);
307 	return rc;
308 }
309 
310 static void rpaphp_eeh_remove_bus_device(struct pci_dev *dev)
311 {
312 	eeh_remove_device(dev);
313 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
314 		struct pci_bus *bus = dev->subordinate;
315 		struct list_head *ln;
316 		if (!bus)
317 			return;
318 		for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
319 			struct pci_dev *pdev = pci_dev_b(ln);
320 			if (pdev)
321 				rpaphp_eeh_remove_bus_device(pdev);
322 		}
323 
324 	}
325 	return;
326 }
327 
328 int rpaphp_unconfig_pci_adapter(struct slot *slot)
329 {
330 	struct pci_dev *dev;
331 	int retval = 0;
332 
333 	list_for_each_entry(dev, slot->dev.pci_devs, bus_list)
334 		rpaphp_eeh_remove_bus_device(dev);
335 
336 	pci_remove_behind_bridge(slot->bridge);
337 	slot->state = NOT_CONFIGURED;
338 	info("%s: devices in slot[%s] unconfigured.\n", __FUNCTION__,
339 	     slot->name);
340 	return retval;
341 }
342 
343 static int setup_pci_hotplug_slot_info(struct slot *slot)
344 {
345 	dbg("%s Initilize the PCI slot's hotplug->info structure ...\n",
346 	    __FUNCTION__);
347 	rpaphp_get_power_status(slot, &slot->hotplug_slot->info->power_status);
348 	rpaphp_get_pci_adapter_status(slot, 1,
349 				      &slot->hotplug_slot->info->
350 				      adapter_status);
351 	if (slot->hotplug_slot->info->adapter_status == NOT_VALID) {
352 		err("%s: NOT_VALID: skip dn->full_name=%s\n",
353 		    __FUNCTION__, slot->dn->full_name);
354 		return -EINVAL;
355 	}
356 	return 0;
357 }
358 
359 static int set_phb_slot_name(struct slot *slot)
360 {
361 	struct device_node *dn;
362 	struct pci_controller *phb;
363 	struct pci_bus *bus;
364 
365 	dn = slot->dn;
366 	if (!dn) {
367 		return -EINVAL;
368 	}
369 	phb = dn->phb;
370 	if (!phb) {
371 		return -EINVAL;
372 	}
373 	bus = phb->bus;
374 	if (!bus) {
375 		return -EINVAL;
376 	}
377 
378 	sprintf(slot->name, "%04x:%02x:%02x.%x", pci_domain_nr(bus),
379 			bus->number, 0, 0);
380 	return 0;
381 }
382 
383 static int setup_pci_slot(struct slot *slot)
384 {
385 	struct pci_bus *bus;
386 	int rc;
387 
388 	if (slot->type == PHB) {
389 		rc = set_phb_slot_name(slot);
390 		if (rc < 0) {
391 			err("%s: failed to set phb slot name\n", __FUNCTION__);
392 			goto exit_rc;
393 		}
394 	} else {
395 		slot->bridge = rpaphp_find_bridge_pdev(slot);
396 		if (!slot->bridge) {
397 			/* slot being added doesn't have pci_dev yet */
398 			err("%s: no pci_dev for bridge dn %s\n",
399 					__FUNCTION__, slot->name);
400 			goto exit_rc;
401 		}
402 
403 		bus = slot->bridge->subordinate;
404 		if (!bus)
405 			goto exit_rc;
406 		slot->dev.pci_devs = &bus->devices;
407 
408 		dbg("%s set slot->name to %s\n",  __FUNCTION__,
409 				pci_name(slot->bridge));
410 		strcpy(slot->name, pci_name(slot->bridge));
411 	}
412 
413 	/* find slot's pci_dev if it's not empty */
414 	if (slot->hotplug_slot->info->adapter_status == EMPTY) {
415 		slot->state = EMPTY;	/* slot is empty */
416 	} else {
417 		/* slot is occupied */
418 		if (!(slot->dn->child)) {
419 			/* non-empty slot has to have child */
420 			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
421 				__FUNCTION__, slot->name);
422 			goto exit_rc;
423 		}
424 
425 		if (slot->hotplug_slot->info->adapter_status == NOT_CONFIGURED) {
426 			dbg("%s CONFIGURING pci adapter in slot[%s]\n",
427 				__FUNCTION__, slot->name);
428 			if (rpaphp_config_pci_adapter(slot)) {
429 				err("%s: CONFIG pci adapter failed\n", __FUNCTION__);
430 				goto exit_rc;
431 			}
432 
433 		} else if (slot->hotplug_slot->info->adapter_status != CONFIGURED) {
434 			err("%s: slot[%s]'s adapter_status is NOT_VALID.\n",
435 				__FUNCTION__, slot->name);
436 			goto exit_rc;
437 		}
438 		print_slot_pci_funcs(slot);
439 		if (!list_empty(slot->dev.pci_devs)) {
440 			slot->state = CONFIGURED;
441 		} else {
442 			/* DLPAR add as opposed to
443 		 	 * boot time */
444 			slot->state = NOT_CONFIGURED;
445 		}
446 	}
447 	return 0;
448 exit_rc:
449 	dealloc_slot_struct(slot);
450 	return -EINVAL;
451 }
452 
453 int register_pci_slot(struct slot *slot)
454 {
455 	int rc = -EINVAL;
456 
457 	slot->dev_type = PCI_DEV;
458 	if ((slot->type == EMBEDDED) || (slot->type == PHB))
459 		slot->removable = 0;
460 	else
461 		slot->removable = 1;
462 	if (setup_pci_hotplug_slot_info(slot))
463 		goto exit_rc;
464 	if (setup_pci_slot(slot))
465 		goto exit_rc;
466 	rc = register_slot(slot);
467 exit_rc:
468 	return rc;
469 }
470 
471 int rpaphp_enable_pci_slot(struct slot *slot)
472 {
473 	int retval = 0, state;
474 
475 	retval = rpaphp_get_sensor_state(slot, &state);
476 	if (retval)
477 		goto exit;
478 	dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
479 	/* if slot is not empty, enable the adapter */
480 	if (state == PRESENT) {
481 		dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
482 		retval = rpaphp_config_pci_adapter(slot);
483 		if (!retval) {
484 			slot->state = CONFIGURED;
485 			dbg("%s: PCI devices in slot[%s] has been configured\n",
486 				__FUNCTION__, slot->name);
487 		} else {
488 			slot->state = NOT_CONFIGURED;
489 			dbg("%s: no pci_dev struct for adapter in slot[%s]\n",
490 			    __FUNCTION__, slot->name);
491 		}
492 	} else if (state == EMPTY) {
493 		dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
494 		slot->state = EMPTY;
495 	} else {
496 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
497 		    slot->name);
498 		slot->state = NOT_VALID;
499 		retval = -EINVAL;
500 	}
501 exit:
502 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
503 	return retval;
504 }
505 
506 struct hotplug_slot *rpaphp_find_hotplug_slot(struct pci_dev *dev)
507 {
508 	struct list_head	*tmp, *n;
509 	struct slot		*slot;
510 
511 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
512 		struct pci_bus *bus;
513 		struct list_head *ln;
514 
515 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
516 		if (slot->bridge == NULL) {
517 			if (slot->dev_type == PCI_DEV) {
518 				printk(KERN_WARNING "PCI slot missing bridge %s %s \n",
519 				                    slot->name, slot->location);
520 			}
521 			continue;
522 		}
523 
524 		bus = slot->bridge->subordinate;
525 		if (!bus) {
526 			continue;  /* should never happen? */
527 		}
528 		for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
529                                 struct pci_dev *pdev = pci_dev_b(ln);
530 				if (pdev == dev)
531 					return slot->hotplug_slot;
532 		}
533 	}
534 
535 	return NULL;
536 }
537 
538 EXPORT_SYMBOL_GPL(rpaphp_find_hotplug_slot);
539