xref: /openbmc/linux/drivers/pci/hotplug/rpaphp_pci.c (revision cd5b50be)
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 <linux/string.h>
27 
28 #include <asm/pci-bridge.h>
29 #include <asm/rtas.h>
30 #include <asm/machdep.h>
31 
32 #include "../pci.h"		/* for pci_add_new_bus */
33 #include "rpaphp.h"
34 
35 static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
36 					struct device_node *dn)
37 {
38 	struct pci_bus *child = NULL;
39 	struct list_head *tmp;
40 	struct device_node *busdn;
41 
42 	busdn = pci_bus_to_OF_node(bus);
43 	if (busdn == dn)
44 		return bus;
45 
46 	list_for_each(tmp, &bus->children) {
47 		child = find_bus_among_children(pci_bus_b(tmp), dn);
48 		if (child)
49 			break;
50 	}
51 	return child;
52 }
53 
54 struct pci_bus *rpaphp_find_pci_bus(struct device_node *dn)
55 {
56 	struct pci_dn *pdn = dn->data;
57 
58 	if (!pdn  || !pdn->phb || !pdn->phb->bus)
59 		return NULL;
60 
61 	return find_bus_among_children(pdn->phb->bus, dn);
62 }
63 EXPORT_SYMBOL_GPL(rpaphp_find_pci_bus);
64 
65 static int rpaphp_get_sensor_state(struct slot *slot, int *state)
66 {
67 	int rc;
68 	int setlevel;
69 
70 	rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
71 
72 	if (rc < 0) {
73 		if (rc == -EFAULT || rc == -EEXIST) {
74 			dbg("%s: slot must be power up to get sensor-state\n",
75 			    __FUNCTION__);
76 
77 			/* some slots have to be powered up
78 			 * before get-sensor will succeed.
79 			 */
80 			rc = rtas_set_power_level(slot->power_domain, POWER_ON,
81 						  &setlevel);
82 			if (rc < 0) {
83 				dbg("%s: power on slot[%s] failed rc=%d.\n",
84 				    __FUNCTION__, slot->name, rc);
85 			} else {
86 				rc = rtas_get_sensor(DR_ENTITY_SENSE,
87 						     slot->index, state);
88 			}
89 		} else if (rc == -ENODEV)
90 			info("%s: slot is unusable\n", __FUNCTION__);
91 		else
92 			err("%s failed to get sensor state\n", __FUNCTION__);
93 	}
94 	return rc;
95 }
96 
97 /**
98  * get_pci_adapter_status - get the status of a slot
99  *
100  * 0-- slot is empty
101  * 1-- adapter is configured
102  * 2-- adapter is not configured
103  * 3-- not valid
104  */
105 int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
106 {
107 	struct pci_bus *bus;
108 	int state, rc;
109 
110 	*value = NOT_VALID;
111 	rc = rpaphp_get_sensor_state(slot, &state);
112 	if (rc)
113 		goto exit;
114 
115  	if (state == EMPTY)
116  		*value = EMPTY;
117  	else if (state == PRESENT) {
118 		if (!is_init) {
119 			/* at run-time slot->state can be changed by */
120 			/* config/unconfig adapter */
121 			*value = slot->state;
122 		} else {
123 			bus = rpaphp_find_pci_bus(slot->dn);
124 			if (bus && !list_empty(&bus->devices))
125 				*value = CONFIGURED;
126 			else
127 				*value = NOT_CONFIGURED;
128 		}
129 	}
130 exit:
131 	return rc;
132 }
133 
134 /* Must be called before pci_bus_add_devices */
135 void rpaphp_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
136 {
137 	struct pci_dev *dev;
138 
139 	list_for_each_entry(dev, &bus->devices, bus_list) {
140 		/*
141 		 * Skip already-present devices (which are on the
142 		 * global device list.)
143 		 */
144 		if (list_empty(&dev->global_list)) {
145 			int i;
146 
147 			/* Need to setup IOMMU tables */
148 			ppc_md.iommu_dev_setup(dev);
149 
150 			if(fix_bus)
151 				pcibios_fixup_device_resources(dev, bus);
152 			pci_read_irq_line(dev);
153 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
154 				struct resource *r = &dev->resource[i];
155 
156 				if (r->parent || !r->start || !r->flags)
157 					continue;
158 				pci_claim_resource(dev, i);
159 			}
160 		}
161 	}
162 }
163 
164 static void rpaphp_eeh_add_bus_device(struct pci_bus *bus)
165 {
166 	struct pci_dev *dev;
167 
168 	list_for_each_entry(dev, &bus->devices, bus_list) {
169 		eeh_add_device_late(dev);
170 		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
171 			struct pci_bus *subbus = dev->subordinate;
172 			if (subbus)
173 				rpaphp_eeh_add_bus_device (subbus);
174 		}
175 	}
176 }
177 
178 static int rpaphp_pci_config_bridge(struct pci_dev *dev)
179 {
180 	u8 sec_busno;
181 	struct pci_bus *child_bus;
182 	struct pci_dev *child_dev;
183 
184 	dbg("Enter %s:  BRIDGE dev=%s\n", __FUNCTION__, pci_name(dev));
185 
186 	/* get busno of downstream bus */
187 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
188 
189 	/* add to children of PCI bridge dev->bus */
190 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
191 	if (!child_bus) {
192 		err("%s: could not add second bus\n", __FUNCTION__);
193 		return -EIO;
194 	}
195 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
196 	/* do pci_scan_child_bus */
197 	pci_scan_child_bus(child_bus);
198 
199 	list_for_each_entry(child_dev, &child_bus->devices, bus_list) {
200 		eeh_add_device_late(child_dev);
201 	}
202 
203 	 /* fixup new pci devices without touching bus struct */
204 	rpaphp_fixup_new_pci_devices(child_bus, 0);
205 
206 	/* Make the discovered devices available */
207 	pci_bus_add_devices(child_bus);
208 	return 0;
209 }
210 
211 void rpaphp_init_new_devs(struct pci_bus *bus)
212 {
213 	rpaphp_fixup_new_pci_devices(bus, 0);
214 	rpaphp_eeh_add_bus_device(bus);
215 }
216 EXPORT_SYMBOL_GPL(rpaphp_init_new_devs);
217 
218 /*****************************************************************************
219  rpaphp_pci_config_slot() will  configure all devices under the
220  given slot->dn and return the the first pci_dev.
221  *****************************************************************************/
222 static struct pci_dev *
223 rpaphp_pci_config_slot(struct pci_bus *bus)
224 {
225 	struct device_node *dn = pci_bus_to_OF_node(bus);
226 	struct pci_dev *dev = NULL;
227 	int slotno;
228 	int num;
229 
230 	dbg("Enter %s: dn=%s bus=%s\n", __FUNCTION__, dn->full_name, bus->name);
231 	if (!dn || !dn->child)
232 		return NULL;
233 
234 	if (_machine == PLATFORM_PSERIES_LPAR) {
235 		of_scan_bus(dn, bus);
236 		if (list_empty(&bus->devices)) {
237 			err("%s: No new device found\n", __FUNCTION__);
238 			return NULL;
239 		}
240 
241 		rpaphp_init_new_devs(bus);
242 		pci_bus_add_devices(bus);
243 		dev = list_entry(&bus->devices, struct pci_dev, bus_list);
244 	} else {
245 		slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
246 
247 		/* pci_scan_slot should find all children */
248 		num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
249 		if (num) {
250 			rpaphp_fixup_new_pci_devices(bus, 1);
251 			pci_bus_add_devices(bus);
252 		}
253 		if (list_empty(&bus->devices)) {
254 			err("%s: No new device found\n", __FUNCTION__);
255 			return NULL;
256 		}
257 		list_for_each_entry(dev, &bus->devices, bus_list) {
258 			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
259 				rpaphp_pci_config_bridge(dev);
260 
261 			rpaphp_eeh_add_bus_device(bus);
262 		}
263 	}
264 
265 	return dev;
266 }
267 
268 static void print_slot_pci_funcs(struct pci_bus *bus)
269 {
270 	struct device_node *dn;
271 	struct pci_dev *dev;
272 
273 	dn = pci_bus_to_OF_node(bus);
274 	if (!dn)
275 		return;
276 
277 	dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, dn->full_name);
278 	list_for_each_entry (dev, &bus->devices, bus_list)
279 		dbg("\t%s\n", pci_name(dev));
280 	return;
281 }
282 
283 int rpaphp_config_pci_adapter(struct pci_bus *bus)
284 {
285 	struct device_node *dn = pci_bus_to_OF_node(bus);
286 	struct pci_dev *dev;
287 	int rc = -ENODEV;
288 
289 	dbg("Entry %s: slot[%s]\n", __FUNCTION__, dn->full_name);
290 	if (!dn)
291 		goto exit;
292 
293 	eeh_add_device_tree_early(dn);
294 	dev = rpaphp_pci_config_slot(bus);
295 	if (!dev) {
296 		err("%s: can't find any devices.\n", __FUNCTION__);
297 		goto exit;
298 	}
299 	print_slot_pci_funcs(bus);
300 	rc = 0;
301 exit:
302 	dbg("Exit %s:  rc=%d\n", __FUNCTION__, rc);
303 	return rc;
304 }
305 EXPORT_SYMBOL_GPL(rpaphp_config_pci_adapter);
306 
307 static void rpaphp_eeh_remove_bus_device(struct pci_dev *dev)
308 {
309 	eeh_remove_device(dev);
310 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
311 		struct pci_bus *bus = dev->subordinate;
312 		struct list_head *ln;
313 		if (!bus)
314 			return;
315 		for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
316 			struct pci_dev *pdev = pci_dev_b(ln);
317 			if (pdev)
318 				rpaphp_eeh_remove_bus_device(pdev);
319 		}
320 
321 	}
322 	return;
323 }
324 
325 int rpaphp_unconfig_pci_adapter(struct pci_bus *bus)
326 {
327 	struct pci_dev *dev, *tmp;
328 
329 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
330 		rpaphp_eeh_remove_bus_device(dev);
331 		pci_remove_bus_device(dev);
332 	}
333 	return 0;
334 }
335 EXPORT_SYMBOL_GPL(rpaphp_unconfig_pci_adapter);
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 (setup_pci_hotplug_slot_info(slot))
427 		goto exit_rc;
428 	if (setup_pci_slot(slot))
429 		goto exit_rc;
430 	rc = register_slot(slot);
431 exit_rc:
432 	return rc;
433 }
434 
435 int rpaphp_enable_pci_slot(struct slot *slot)
436 {
437 	int retval = 0, state;
438 
439 	retval = rpaphp_get_sensor_state(slot, &state);
440 	if (retval)
441 		goto exit;
442 	dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
443 	/* if slot is not empty, enable the adapter */
444 	if (state == PRESENT) {
445 		dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
446 		retval = rpaphp_config_pci_adapter(slot->bus);
447 		if (!retval) {
448 			slot->state = CONFIGURED;
449 			info("%s: devices in slot[%s] configured\n",
450 					__FUNCTION__, slot->name);
451 		} else {
452 			slot->state = NOT_CONFIGURED;
453 			dbg("%s: no pci_dev struct for adapter in slot[%s]\n",
454 			    __FUNCTION__, slot->name);
455 		}
456 	} else if (state == EMPTY) {
457 		dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
458 		slot->state = EMPTY;
459 	} else {
460 		err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
461 		    slot->name);
462 		slot->state = NOT_VALID;
463 		retval = -EINVAL;
464 	}
465 exit:
466 	dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
467 	return retval;
468 }
469