xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_pci.c (revision 940903c5)
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 static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
34 					struct device_node *dn)
35 {
36 	struct pci_bus *child = NULL;
37 	struct list_head *tmp;
38 	struct device_node *busdn;
39 
40 	busdn = pci_bus_to_OF_node(bus);
41 	if (busdn == dn)
42 		return bus;
43 
44 	list_for_each(tmp, &bus->children) {
45 		child = find_bus_among_children(pci_bus_b(tmp), dn);
46 		if (child)
47 			break;
48 	}
49 	return child;
50 }
51 
52 static struct pci_bus *rpaphp_find_pci_bus(struct device_node *dn)
53 {
54 	if (!dn->phb || !dn->phb->bus)
55 		return NULL;
56 
57 	return find_bus_among_children(dn->phb->bus, dn);
58 }
59 
60 int rpaphp_claim_resource(struct pci_dev *dev, int resource)
61 {
62 	struct resource *res = &dev->resource[resource];
63 	struct resource *root = pci_find_parent_resource(dev, res);
64 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
65 	int err = -EINVAL;
66 
67 	if (root != NULL) {
68 		err = request_resource(root, res);
69 	}
70 
71 	if (err) {
72 		err("PCI: %s region %d of %s %s [%lx:%lx]\n",
73 		    root ? "Address space collision on" :
74 		    "No parent found for",
75 		    resource, dtype, pci_name(dev), res->start, res->end);
76 	}
77 	return err;
78 }
79 
80 EXPORT_SYMBOL_GPL(rpaphp_claim_resource);
81 
82 static int rpaphp_get_sensor_state(struct slot *slot, int *state)
83 {
84 	int rc;
85 	int setlevel;
86 
87 	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
88 
89 	if (rc < 0) {
90 		if (rc == -EFAULT || rc == -EEXIST) {
91 			dbg("%s: slot must be power up to get sensor-state\n",
92 			    __FUNCTION__);
93 
94 			/* some slots have to be powered up
95 			 * before get-sensor will succeed.
96 			 */
97 			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
98 						  &setlevel);
99 			if (rc < 0) {
100 				dbg("%s: power on slot[%s] failed rc=%d.\n",
101 				    __FUNCTION__, slot->name, rc);
102 			} else {
103 				rc = rtas_get_sensor(DR_ENTITY_SENSE,
104 						     slot->index, state);
105 			}
106 		} else if (rc == -ENODEV)
107 			info("%s: slot is unusable\n", __FUNCTION__);
108 		else
109 			err("%s failed to get sensor state\n", __FUNCTION__);
110 	}
111 	return rc;
112 }
113 
114 /**
115  * get_pci_adapter_status - get the status of a slot
116  *
117  * 0-- slot is empty
118  * 1-- adapter is configured
119  * 2-- adapter is not configured
120  * 3-- not valid
121  */
122 int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
123 {
124 	struct pci_bus *bus;
125 	int state, rc;
126 
127 	*value = NOT_VALID;
128 	rc = rpaphp_get_sensor_state(slot, &state);
129 	if (rc)
130 		goto exit;
131 
132  	if ((state == EMPTY) || (slot->type == PHB)) {
133  		dbg("slot is empty\n");
134  		*value = EMPTY;
135  	}
136  	else if (state == PRESENT) {
137 		if (!is_init) {
138 			/* at run-time slot->state can be changed by */
139 			/* config/unconfig adapter */
140 			*value = slot->state;
141 		} else {
142 			bus = rpaphp_find_pci_bus(slot->dn);
143 			if (bus && !list_empty(&bus->devices))
144 				*value = CONFIGURED;
145 			else
146 				*value = NOT_CONFIGURED;
147 		}
148 	}
149 exit:
150 	return rc;
151 }
152 
153 /* Must be called before pci_bus_add_devices */
154 static void
155 rpaphp_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
156 {
157 	struct pci_dev *dev;
158 
159 	list_for_each_entry(dev, &bus->devices, bus_list) {
160 		/*
161 		 * Skip already-present devices (which are on the
162 		 * global device list.)
163 		 */
164 		if (list_empty(&dev->global_list)) {
165 			int i;
166 
167 			/* Need to setup IOMMU tables */
168 			ppc_md.iommu_dev_setup(dev);
169 
170 			if(fix_bus)
171 				pcibios_fixup_device_resources(dev, bus);
172 			pci_read_irq_line(dev);
173 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
174 				struct resource *r = &dev->resource[i];
175 
176 				if (r->parent || !r->start || !r->flags)
177 					continue;
178 				rpaphp_claim_resource(dev, i);
179 			}
180 		}
181 	}
182 }
183 
184 static int rpaphp_pci_config_bridge(struct pci_dev *dev)
185 {
186 	u8 sec_busno;
187 	struct pci_bus *child_bus;
188 	struct pci_dev *child_dev;
189 
190 	dbg("Enter %s:  BRIDGE dev=%s\n", __FUNCTION__, pci_name(dev));
191 
192 	/* get busno of downstream bus */
193 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
194 
195 	/* add to children of PCI bridge dev->bus */
196 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
197 	if (!child_bus) {
198 		err("%s: could not add second bus\n", __FUNCTION__);
199 		return -EIO;
200 	}
201 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
202 	/* do pci_scan_child_bus */
203 	pci_scan_child_bus(child_bus);
204 
205 	list_for_each_entry(child_dev, &child_bus->devices, bus_list) {
206 		eeh_add_device_late(child_dev);
207 	}
208 
209 	 /* fixup new pci devices without touching bus struct */
210 	rpaphp_fixup_new_pci_devices(child_bus, 0);
211 
212 	/* Make the discovered devices available */
213 	pci_bus_add_devices(child_bus);
214 	return 0;
215 }
216 
217 /*****************************************************************************
218  rpaphp_pci_config_slot() will  configure all devices under the
219  given slot->dn and return the the first pci_dev.
220  *****************************************************************************/
221 static struct pci_dev *
222 rpaphp_pci_config_slot(struct pci_bus *bus)
223 {
224 	struct device_node *dn = pci_bus_to_OF_node(bus);
225 	struct pci_dev *dev = NULL;
226 	int slotno;
227 	int num;
228 
229 	dbg("Enter %s: dn=%s bus=%s\n", __FUNCTION__, dn->full_name, bus->name);
230 	if (!dn || !dn->child)
231 		return NULL;
232 
233 	slotno = PCI_SLOT(dn->child->devfn);
234 
235 	/* pci_scan_slot should find all children */
236 	num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
237 	if (num) {
238 		rpaphp_fixup_new_pci_devices(bus, 1);
239 		pci_bus_add_devices(bus);
240 	}
241 	if (list_empty(&bus->devices)) {
242 		err("%s: No new device found\n", __FUNCTION__);
243 		return NULL;
244 	}
245 	list_for_each_entry(dev, &bus->devices, bus_list) {
246 		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
247 			rpaphp_pci_config_bridge(dev);
248 	}
249 
250 	return dev;
251 }
252 
253 static void enable_eeh(struct device_node *dn)
254 {
255 	struct device_node *sib;
256 
257 	for (sib = dn->child; sib; sib = sib->sibling)
258 		enable_eeh(sib);
259 	eeh_add_device_early(dn);
260 	return;
261 
262 }
263 
264 static void print_slot_pci_funcs(struct pci_bus *bus)
265 {
266 	struct device_node *dn;
267 	struct pci_dev *dev;
268 
269 	dn = pci_bus_to_OF_node(bus);
270 	if (!dn)
271 		return;
272 
273 	dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, dn->full_name);
274 	list_for_each_entry (dev, &bus->devices, bus_list)
275 		dbg("\t%s\n", pci_name(dev));
276 	return;
277 }
278 
279 int rpaphp_config_pci_adapter(struct pci_bus *bus)
280 {
281 	struct device_node *dn = pci_bus_to_OF_node(bus);
282 	struct pci_dev *dev;
283 	int rc = -ENODEV;
284 
285 	dbg("Entry %s: slot[%s]\n", __FUNCTION__, dn->full_name);
286 	if (!dn)
287 		goto exit;
288 
289 	enable_eeh(dn);
290 	dev = rpaphp_pci_config_slot(bus);
291 	if (!dev) {
292 		err("%s: can't find any devices.\n", __FUNCTION__);
293 		goto exit;
294 	}
295 	print_slot_pci_funcs(bus);
296 	rc = 0;
297 exit:
298 	dbg("Exit %s:  rc=%d\n", __FUNCTION__, rc);
299 	return rc;
300 }
301 EXPORT_SYMBOL_GPL(rpaphp_config_pci_adapter);
302 
303 static void rpaphp_eeh_remove_bus_device(struct pci_dev *dev)
304 {
305 	eeh_remove_device(dev);
306 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
307 		struct pci_bus *bus = dev->subordinate;
308 		struct list_head *ln;
309 		if (!bus)
310 			return;
311 		for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
312 			struct pci_dev *pdev = pci_dev_b(ln);
313 			if (pdev)
314 				rpaphp_eeh_remove_bus_device(pdev);
315 		}
316 
317 	}
318 	return;
319 }
320 
321 int rpaphp_unconfig_pci_adapter(struct slot *slot)
322 {
323 	struct pci_dev *dev, *tmp;
324 	int retval = 0;
325 
326 	list_for_each_entry_safe(dev, tmp, slot->pci_devs, bus_list) {
327 		rpaphp_eeh_remove_bus_device(dev);
328 		pci_remove_bus_device(dev);
329 	}
330 
331 	slot->state = NOT_CONFIGURED;
332 	info("%s: devices in slot[%s] unconfigured.\n", __FUNCTION__,
333 	     slot->name);
334 	return retval;
335 }
336 
337 static int setup_pci_hotplug_slot_info(struct slot *slot)
338 {
339 	dbg("%s Initilize the PCI slot's hotplug->info structure ...\n",
340 	    __FUNCTION__);
341 	rpaphp_get_power_status(slot, &slot->hotplug_slot->info->power_status);
342 	rpaphp_get_pci_adapter_status(slot, 1,
343 				      &slot->hotplug_slot->info->
344 				      adapter_status);
345 	if (slot->hotplug_slot->info->adapter_status == NOT_VALID) {
346 		err("%s: NOT_VALID: skip dn->full_name=%s\n",
347 		    __FUNCTION__, slot->dn->full_name);
348 		return -EINVAL;
349 	}
350 	return 0;
351 }
352 
353 static void set_slot_name(struct slot *slot)
354 {
355 	struct pci_bus *bus = slot->bus;
356 	struct pci_dev *bridge;
357 
358 	bridge = bus->self;
359 	if (bridge)
360 		strcpy(slot->name, pci_name(bridge));
361 	else
362 		sprintf(slot->name, "%04x:%02x:00.0", pci_domain_nr(bus),
363 			bus->number);
364 }
365 
366 static int setup_pci_slot(struct slot *slot)
367 {
368 	struct device_node *dn = slot->dn;
369 	struct pci_bus *bus;
370 
371 	BUG_ON(!dn);
372 	bus = rpaphp_find_pci_bus(dn);
373 	if (!bus) {
374 		err("%s: no pci_bus for dn %s\n", __FUNCTION__, dn->full_name);
375 		goto exit_rc;
376 	}
377 
378 	slot->bus = bus;
379 	slot->pci_devs = &bus->devices;
380 	set_slot_name(slot);
381 
382 	/* find slot's pci_dev if it's not empty */
383 	if (slot->hotplug_slot->info->adapter_status == EMPTY) {
384 		slot->state = EMPTY;	/* slot is empty */
385 	} else {
386 		/* slot is occupied */
387 		if (!dn->child) {
388 			/* non-empty slot has to have child */
389 			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
390 				__FUNCTION__, slot->name);
391 			goto exit_rc;
392 		}
393 
394 		if (slot->hotplug_slot->info->adapter_status == NOT_CONFIGURED) {
395 			dbg("%s CONFIGURING pci adapter in slot[%s]\n",
396 				__FUNCTION__, slot->name);
397 			if (rpaphp_config_pci_adapter(slot->bus)) {
398 				err("%s: CONFIG pci adapter failed\n", __FUNCTION__);
399 				goto exit_rc;
400 			}
401 
402 		} else if (slot->hotplug_slot->info->adapter_status != CONFIGURED) {
403 			err("%s: slot[%s]'s adapter_status is NOT_VALID.\n",
404 				__FUNCTION__, slot->name);
405 			goto exit_rc;
406 		}
407 		print_slot_pci_funcs(slot->bus);
408 		if (!list_empty(slot->pci_devs)) {
409 			slot->state = CONFIGURED;
410 		} else {
411 			/* DLPAR add as opposed to
412 		 	 * boot time */
413 			slot->state = NOT_CONFIGURED;
414 		}
415 	}
416 	return 0;
417 exit_rc:
418 	dealloc_slot_struct(slot);
419 	return -EINVAL;
420 }
421 
422 int register_pci_slot(struct slot *slot)
423 {
424 	int rc = -EINVAL;
425 
426 	if ((slot->type == EMBEDDED) || (slot->type == PHB))
427 		slot->removable = 0;
428 	else
429 		slot->removable = 1;
430 	if (setup_pci_hotplug_slot_info(slot))
431 		goto exit_rc;
432 	if (setup_pci_slot(slot))
433 		goto exit_rc;
434 	rc = register_slot(slot);
435 exit_rc:
436 	return rc;
437 }
438 
439 int rpaphp_enable_pci_slot(struct slot *slot)
440 {
441 	int retval = 0, state;
442 
443 	retval = rpaphp_get_sensor_state(slot, &state);
444 	if (retval)
445 		goto exit;
446 	dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
447 	/* if slot is not empty, enable the adapter */
448 	if (state == PRESENT) {
449 		dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
450 		retval = rpaphp_config_pci_adapter(slot->bus);
451 		if (!retval) {
452 			slot->state = CONFIGURED;
453 			dbg("%s: PCI devices in slot[%s] has been configured\n",
454 				__FUNCTION__, slot->name);
455 		} else {
456 			slot->state = NOT_CONFIGURED;
457 			dbg("%s: no pci_dev struct for adapter in slot[%s]\n",
458 			    __FUNCTION__, slot->name);
459 		}
460 	} else if (state == EMPTY) {
461 		dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
462 		slot->state = EMPTY;
463 	} else {
464 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
465 		    slot->name);
466 		slot->state = NOT_VALID;
467 		retval = -EINVAL;
468 	}
469 exit:
470 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
471 	return retval;
472 }
473