xref: /linux/drivers/pci/hotplug/rpaphp_pci.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
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 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 EXPORT_SYMBOL_GPL(rpaphp_find_pci_bus);
60 
61 int rpaphp_claim_resource(struct pci_dev *dev, int resource)
62 {
63 	struct resource *res = &dev->resource[resource];
64 	struct resource *root = pci_find_parent_resource(dev, res);
65 	char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
66 	int err = -EINVAL;
67 
68 	if (root != NULL) {
69 		err = request_resource(root, res);
70 	}
71 
72 	if (err) {
73 		err("PCI: %s region %d of %s %s [%lx:%lx]\n",
74 		    root ? "Address space collision on" :
75 		    "No parent found for",
76 		    resource, dtype, pci_name(dev), res->start, res->end);
77 	}
78 	return err;
79 }
80 
81 EXPORT_SYMBOL_GPL(rpaphp_claim_resource);
82 
83 static int rpaphp_get_sensor_state(struct slot *slot, int *state)
84 {
85 	int rc;
86 	int setlevel;
87 
88 	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
89 
90 	if (rc < 0) {
91 		if (rc == -EFAULT || rc == -EEXIST) {
92 			dbg("%s: slot must be power up to get sensor-state\n",
93 			    __FUNCTION__);
94 
95 			/* some slots have to be powered up
96 			 * before get-sensor will succeed.
97 			 */
98 			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
99 						  &setlevel);
100 			if (rc < 0) {
101 				dbg("%s: power on slot[%s] failed rc=%d.\n",
102 				    __FUNCTION__, slot->name, rc);
103 			} else {
104 				rc = rtas_get_sensor(DR_ENTITY_SENSE,
105 						     slot->index, state);
106 			}
107 		} else if (rc == -ENODEV)
108 			info("%s: slot is unusable\n", __FUNCTION__);
109 		else
110 			err("%s failed to get sensor state\n", __FUNCTION__);
111 	}
112 	return rc;
113 }
114 
115 /**
116  * get_pci_adapter_status - get the status of a slot
117  *
118  * 0-- slot is empty
119  * 1-- adapter is configured
120  * 2-- adapter is not configured
121  * 3-- not valid
122  */
123 int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
124 {
125 	struct pci_bus *bus;
126 	int state, rc;
127 
128 	*value = NOT_VALID;
129 	rc = rpaphp_get_sensor_state(slot, &state);
130 	if (rc)
131 		goto exit;
132 
133  	if (state == EMPTY)
134  		*value = EMPTY;
135  	else if (state == PRESENT) {
136 		if (!is_init) {
137 			/* at run-time slot->state can be changed by */
138 			/* config/unconfig adapter */
139 			*value = slot->state;
140 		} else {
141 			bus = rpaphp_find_pci_bus(slot->dn);
142 			if (bus && !list_empty(&bus->devices))
143 				*value = CONFIGURED;
144 			else
145 				*value = NOT_CONFIGURED;
146 		}
147 	}
148 exit:
149 	return rc;
150 }
151 
152 /* Must be called before pci_bus_add_devices */
153 static void
154 rpaphp_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
155 {
156 	struct pci_dev *dev;
157 
158 	list_for_each_entry(dev, &bus->devices, bus_list) {
159 		/*
160 		 * Skip already-present devices (which are on the
161 		 * global device list.)
162 		 */
163 		if (list_empty(&dev->global_list)) {
164 			int i;
165 
166 			/* Need to setup IOMMU tables */
167 			ppc_md.iommu_dev_setup(dev);
168 
169 			if(fix_bus)
170 				pcibios_fixup_device_resources(dev, bus);
171 			pci_read_irq_line(dev);
172 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
173 				struct resource *r = &dev->resource[i];
174 
175 				if (r->parent || !r->start || !r->flags)
176 					continue;
177 				rpaphp_claim_resource(dev, i);
178 			}
179 		}
180 	}
181 }
182 
183 static int rpaphp_pci_config_bridge(struct pci_dev *dev)
184 {
185 	u8 sec_busno;
186 	struct pci_bus *child_bus;
187 	struct pci_dev *child_dev;
188 
189 	dbg("Enter %s:  BRIDGE dev=%s\n", __FUNCTION__, pci_name(dev));
190 
191 	/* get busno of downstream bus */
192 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
193 
194 	/* add to children of PCI bridge dev->bus */
195 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
196 	if (!child_bus) {
197 		err("%s: could not add second bus\n", __FUNCTION__);
198 		return -EIO;
199 	}
200 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
201 	/* do pci_scan_child_bus */
202 	pci_scan_child_bus(child_bus);
203 
204 	list_for_each_entry(child_dev, &child_bus->devices, bus_list) {
205 		eeh_add_device_late(child_dev);
206 	}
207 
208 	 /* fixup new pci devices without touching bus struct */
209 	rpaphp_fixup_new_pci_devices(child_bus, 0);
210 
211 	/* Make the discovered devices available */
212 	pci_bus_add_devices(child_bus);
213 	return 0;
214 }
215 
216 /*****************************************************************************
217  rpaphp_pci_config_slot() will  configure all devices under the
218  given slot->dn and return the the first pci_dev.
219  *****************************************************************************/
220 static struct pci_dev *
221 rpaphp_pci_config_slot(struct pci_bus *bus)
222 {
223 	struct device_node *dn = pci_bus_to_OF_node(bus);
224 	struct pci_dev *dev = NULL;
225 	int slotno;
226 	int num;
227 
228 	dbg("Enter %s: dn=%s bus=%s\n", __FUNCTION__, dn->full_name, bus->name);
229 	if (!dn || !dn->child)
230 		return NULL;
231 
232 	slotno = PCI_SLOT(dn->child->devfn);
233 
234 	/* pci_scan_slot should find all children */
235 	num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
236 	if (num) {
237 		rpaphp_fixup_new_pci_devices(bus, 1);
238 		pci_bus_add_devices(bus);
239 	}
240 	if (list_empty(&bus->devices)) {
241 		err("%s: No new device found\n", __FUNCTION__);
242 		return NULL;
243 	}
244 	list_for_each_entry(dev, &bus->devices, bus_list) {
245 		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
246 			rpaphp_pci_config_bridge(dev);
247 	}
248 
249 	return dev;
250 }
251 
252 static void enable_eeh(struct device_node *dn)
253 {
254 	struct device_node *sib;
255 
256 	for (sib = dn->child; sib; sib = sib->sibling)
257 		enable_eeh(sib);
258 	eeh_add_device_early(dn);
259 	return;
260 
261 }
262 
263 static void print_slot_pci_funcs(struct pci_bus *bus)
264 {
265 	struct device_node *dn;
266 	struct pci_dev *dev;
267 
268 	dn = pci_bus_to_OF_node(bus);
269 	if (!dn)
270 		return;
271 
272 	dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, dn->full_name);
273 	list_for_each_entry (dev, &bus->devices, bus_list)
274 		dbg("\t%s\n", pci_name(dev));
275 	return;
276 }
277 
278 int rpaphp_config_pci_adapter(struct pci_bus *bus)
279 {
280 	struct device_node *dn = pci_bus_to_OF_node(bus);
281 	struct pci_dev *dev;
282 	int rc = -ENODEV;
283 
284 	dbg("Entry %s: slot[%s]\n", __FUNCTION__, dn->full_name);
285 	if (!dn)
286 		goto exit;
287 
288 	enable_eeh(dn);
289 	dev = rpaphp_pci_config_slot(bus);
290 	if (!dev) {
291 		err("%s: can't find any devices.\n", __FUNCTION__);
292 		goto exit;
293 	}
294 	print_slot_pci_funcs(bus);
295 	rc = 0;
296 exit:
297 	dbg("Exit %s:  rc=%d\n", __FUNCTION__, rc);
298 	return rc;
299 }
300 EXPORT_SYMBOL_GPL(rpaphp_config_pci_adapter);
301 
302 static void rpaphp_eeh_remove_bus_device(struct pci_dev *dev)
303 {
304 	eeh_remove_device(dev);
305 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
306 		struct pci_bus *bus = dev->subordinate;
307 		struct list_head *ln;
308 		if (!bus)
309 			return;
310 		for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
311 			struct pci_dev *pdev = pci_dev_b(ln);
312 			if (pdev)
313 				rpaphp_eeh_remove_bus_device(pdev);
314 		}
315 
316 	}
317 	return;
318 }
319 
320 int rpaphp_unconfig_pci_adapter(struct slot *slot)
321 {
322 	struct pci_dev *dev, *tmp;
323 	int retval = 0;
324 
325 	list_for_each_entry_safe(dev, tmp, slot->pci_devs, bus_list) {
326 		rpaphp_eeh_remove_bus_device(dev);
327 		pci_remove_bus_device(dev);
328 	}
329 
330 	slot->state = NOT_CONFIGURED;
331 	info("%s: devices in slot[%s] unconfigured.\n", __FUNCTION__,
332 	     slot->name);
333 	return retval;
334 }
335 
336 static int setup_pci_hotplug_slot_info(struct slot *slot)
337 {
338 	dbg("%s Initilize the PCI slot's hotplug->info structure ...\n",
339 	    __FUNCTION__);
340 	rpaphp_get_power_status(slot, &slot->hotplug_slot->info->power_status);
341 	rpaphp_get_pci_adapter_status(slot, 1,
342 				      &slot->hotplug_slot->info->
343 				      adapter_status);
344 	if (slot->hotplug_slot->info->adapter_status == NOT_VALID) {
345 		err("%s: NOT_VALID: skip dn->full_name=%s\n",
346 		    __FUNCTION__, slot->dn->full_name);
347 		return -EINVAL;
348 	}
349 	return 0;
350 }
351 
352 static void set_slot_name(struct slot *slot)
353 {
354 	struct pci_bus *bus = slot->bus;
355 	struct pci_dev *bridge;
356 
357 	bridge = bus->self;
358 	if (bridge)
359 		strcpy(slot->name, pci_name(bridge));
360 	else
361 		sprintf(slot->name, "%04x:%02x:00.0", pci_domain_nr(bus),
362 			bus->number);
363 }
364 
365 static int setup_pci_slot(struct slot *slot)
366 {
367 	struct device_node *dn = slot->dn;
368 	struct pci_bus *bus;
369 
370 	BUG_ON(!dn);
371 	bus = rpaphp_find_pci_bus(dn);
372 	if (!bus) {
373 		err("%s: no pci_bus for dn %s\n", __FUNCTION__, dn->full_name);
374 		goto exit_rc;
375 	}
376 
377 	slot->bus = bus;
378 	slot->pci_devs = &bus->devices;
379 	set_slot_name(slot);
380 
381 	/* find slot's pci_dev if it's not empty */
382 	if (slot->hotplug_slot->info->adapter_status == EMPTY) {
383 		slot->state = EMPTY;	/* slot is empty */
384 	} else {
385 		/* slot is occupied */
386 		if (!dn->child) {
387 			/* non-empty slot has to have child */
388 			err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
389 				__FUNCTION__, slot->name);
390 			goto exit_rc;
391 		}
392 
393 		if (slot->hotplug_slot->info->adapter_status == NOT_CONFIGURED) {
394 			dbg("%s CONFIGURING pci adapter in slot[%s]\n",
395 				__FUNCTION__, slot->name);
396 			if (rpaphp_config_pci_adapter(slot->bus)) {
397 				err("%s: CONFIG pci adapter failed\n", __FUNCTION__);
398 				goto exit_rc;
399 			}
400 
401 		} else if (slot->hotplug_slot->info->adapter_status != CONFIGURED) {
402 			err("%s: slot[%s]'s adapter_status is NOT_VALID.\n",
403 				__FUNCTION__, slot->name);
404 			goto exit_rc;
405 		}
406 		print_slot_pci_funcs(slot->bus);
407 		if (!list_empty(slot->pci_devs)) {
408 			slot->state = CONFIGURED;
409 		} else {
410 			/* DLPAR add as opposed to
411 		 	 * boot time */
412 			slot->state = NOT_CONFIGURED;
413 		}
414 	}
415 	return 0;
416 exit_rc:
417 	dealloc_slot_struct(slot);
418 	return -EINVAL;
419 }
420 
421 int register_pci_slot(struct slot *slot)
422 {
423 	int rc = -EINVAL;
424 
425 	if (setup_pci_hotplug_slot_info(slot))
426 		goto exit_rc;
427 	if (setup_pci_slot(slot))
428 		goto exit_rc;
429 	rc = register_slot(slot);
430 exit_rc:
431 	return rc;
432 }
433 
434 int rpaphp_enable_pci_slot(struct slot *slot)
435 {
436 	int retval = 0, state;
437 
438 	retval = rpaphp_get_sensor_state(slot, &state);
439 	if (retval)
440 		goto exit;
441 	dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
442 	/* if slot is not empty, enable the adapter */
443 	if (state == PRESENT) {
444 		dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
445 		retval = rpaphp_config_pci_adapter(slot->bus);
446 		if (!retval) {
447 			slot->state = CONFIGURED;
448 			dbg("%s: PCI devices in slot[%s] has been configured\n",
449 				__FUNCTION__, slot->name);
450 		} else {
451 			slot->state = NOT_CONFIGURED;
452 			dbg("%s: no pci_dev struct for adapter in slot[%s]\n",
453 			    __FUNCTION__, slot->name);
454 		}
455 	} else if (state == EMPTY) {
456 		dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
457 		slot->state = EMPTY;
458 	} else {
459 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
460 		    slot->name);
461 		slot->state = NOT_VALID;
462 		retval = -EINVAL;
463 	}
464 exit:
465 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
466 	return retval;
467 }
468