xref: /linux/drivers/pci/hotplug/rpadlpar_core.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
1 /*
2  * Interface for Dynamic Logical Partitioning of I/O Slots on
3  * RPA-compliant PPC64 platform.
4  *
5  * John Rose <johnrose@austin.ibm.com>
6  * Linda Xie <lxie@us.ibm.com>
7  *
8  * October 2003
9  *
10  * Copyright (C) 2003 IBM.
11  *
12  *      This program is free software; you can redistribute it and/or
13  *      modify it under the terms of the GNU General Public License
14  *      as published by the Free Software Foundation; either version
15  *      2 of the License, or (at your option) any later version.
16  */
17 #include <linux/init.h>
18 #include <linux/pci.h>
19 #include <asm/pci-bridge.h>
20 #include <asm/semaphore.h>
21 #include <asm/rtas.h>
22 #include <asm/vio.h>
23 #include "../pci.h"
24 #include "rpaphp.h"
25 #include "rpadlpar.h"
26 
27 static DECLARE_MUTEX(rpadlpar_sem);
28 
29 #define DLPAR_MODULE_NAME "rpadlpar_io"
30 
31 #define NODE_TYPE_VIO  1
32 #define NODE_TYPE_SLOT 2
33 #define NODE_TYPE_PHB  3
34 
35 static struct device_node *find_vio_slot_node(char *drc_name)
36 {
37 	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
38 	struct device_node *dn = NULL;
39 	char *name;
40 	int rc;
41 
42 	if (!parent)
43 		return NULL;
44 
45 	while ((dn = of_get_next_child(parent, dn))) {
46 		rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
47 		if ((rc == 0) && (!strcmp(drc_name, name)))
48 			break;
49 	}
50 
51 	return dn;
52 }
53 
54 /* Find dlpar-capable pci node that contains the specified name and type */
55 static struct device_node *find_php_slot_pci_node(char *drc_name,
56 						  char *drc_type)
57 {
58 	struct device_node *np = NULL;
59 	char *name;
60 	char *type;
61 	int rc;
62 
63 	while ((np = of_find_node_by_type(np, "pci"))) {
64 		rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
65 		if (rc == 0)
66 			if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
67 				break;
68 	}
69 
70 	return np;
71 }
72 
73 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
74 {
75 	struct device_node *dn;
76 
77 	dn = find_php_slot_pci_node(drc_name, "SLOT");
78 	if (dn) {
79 		*node_type = NODE_TYPE_SLOT;
80 		return dn;
81 	}
82 
83 	dn = find_php_slot_pci_node(drc_name, "PHB");
84 	if (dn) {
85 		*node_type = NODE_TYPE_PHB;
86 		return dn;
87 	}
88 
89 	dn = find_vio_slot_node(drc_name);
90 	if (dn) {
91 		*node_type = NODE_TYPE_VIO;
92 		return dn;
93 	}
94 
95 	return NULL;
96 }
97 
98 static struct slot *find_slot(struct device_node *dn)
99 {
100 	struct list_head *tmp, *n;
101 	struct slot *slot;
102 
103         list_for_each_safe(tmp, n, &rpaphp_slot_head) {
104                 slot = list_entry(tmp, struct slot, rpaphp_slot_list);
105                 if (slot->dn == dn)
106                         return slot;
107         }
108 
109         return NULL;
110 }
111 
112 static void rpadlpar_claim_one_bus(struct pci_bus *b)
113 {
114 	struct list_head *ld;
115 	struct pci_bus *child_bus;
116 
117 	for (ld = b->devices.next; ld != &b->devices; ld = ld->next) {
118 		struct pci_dev *dev = pci_dev_b(ld);
119 		int i;
120 
121 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
122 			struct resource *r = &dev->resource[i];
123 
124 			if (r->parent || !r->start || !r->flags)
125 				continue;
126 			rpaphp_claim_resource(dev, i);
127 		}
128 	}
129 
130 	list_for_each_entry(child_bus, &b->children, node)
131 		rpadlpar_claim_one_bus(child_bus);
132 }
133 
134 static int pci_add_secondary_bus(struct device_node *dn,
135 		struct pci_dev *bridge_dev)
136 {
137 	struct pci_dn *pdn = dn->data;
138 	struct pci_controller *hose = pdn->phb;
139 	struct pci_bus *child;
140 	u8 sec_busno;
141 
142 	/* Get busno of downstream bus */
143 	pci_read_config_byte(bridge_dev, PCI_SECONDARY_BUS, &sec_busno);
144 
145 	/* Allocate and add to children of bridge_dev->bus */
146 	child = pci_add_new_bus(bridge_dev->bus, bridge_dev, sec_busno);
147 	if (!child) {
148 		printk(KERN_ERR "%s: could not add secondary bus\n", __FUNCTION__);
149 		return -ENOMEM;
150 	}
151 
152 	sprintf(child->name, "PCI Bus #%02x", child->number);
153 
154 	/* Fixup subordinate bridge bases and resources */
155 	pcibios_fixup_bus(child);
156 
157 	/* Claim new bus resources */
158 	rpadlpar_claim_one_bus(bridge_dev->bus);
159 
160 	if (hose->last_busno < child->number)
161 		hose->last_busno = child->number;
162 
163 	pdn->bussubno = child->number;
164 
165 	/* ioremap() for child bus, which may or may not succeed */
166 	remap_bus_range(child);
167 
168 	return 0;
169 }
170 
171 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
172 					struct device_node *dev_dn)
173 {
174 	struct pci_dev *tmp = NULL;
175 	struct device_node *child_dn;
176 
177 	list_for_each_entry(tmp, &parent->devices, bus_list) {
178 		child_dn = pci_device_to_OF_node(tmp);
179 		if (child_dn == dev_dn)
180 			return tmp;
181 	}
182 	return NULL;
183 }
184 
185 static struct pci_dev *dlpar_pci_add_bus(struct device_node *dn)
186 {
187 	struct pci_dn *pdn = dn->data;
188 	struct pci_controller *hose = pdn->phb;
189 	struct pci_dev *dev = NULL;
190 
191 	/* Scan phb bus for EADS device, adding new one to bus->devices */
192 	if (!pci_scan_single_device(hose->bus, pdn->devfn)) {
193 		printk(KERN_ERR "%s: found no device on bus\n", __FUNCTION__);
194 		return NULL;
195 	}
196 
197 	/* Add new devices to global lists.  Register in proc, sysfs. */
198 	pci_bus_add_devices(hose->bus);
199 
200 	/* Confirm new bridge dev was created */
201 	dev = dlpar_find_new_dev(hose->bus, dn);
202 	if (dev) {
203 		if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
204 			printk(KERN_ERR "%s: unexpected header type %d\n",
205 				__FUNCTION__, dev->hdr_type);
206 			return NULL;
207 		}
208 
209 		if (pci_add_secondary_bus(dn, dev))
210 			return NULL;
211 	}
212 
213 	return dev;
214 }
215 
216 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
217 {
218 	struct pci_dev *dev;
219 	int rc;
220 
221 	if (rpaphp_find_pci_bus(dn))
222 		return -EINVAL;
223 
224 	/* Add pci bus */
225 	dev = dlpar_pci_add_bus(dn);
226 	if (!dev) {
227 		printk(KERN_ERR "%s: unable to add bus %s\n", __FUNCTION__,
228 			drc_name);
229 		return -EIO;
230 	}
231 
232 	if (dn->child) {
233 		rc = rpaphp_config_pci_adapter(dev->subordinate);
234 		if (rc < 0) {
235 			printk(KERN_ERR "%s: unable to enable slot %s\n",
236 				__FUNCTION__, drc_name);
237 			return -EIO;
238 		}
239 	}
240 
241 	/* Add hotplug slot */
242 	if (rpaphp_add_slot(dn)) {
243 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
244 			__FUNCTION__, drc_name);
245 		return -EIO;
246 	}
247 	return 0;
248 }
249 
250 static int dlpar_remove_root_bus(struct pci_controller *phb)
251 {
252 	struct pci_bus *phb_bus;
253 	int rc;
254 
255 	phb_bus = phb->bus;
256 	if (!(list_empty(&phb_bus->children) &&
257 	      list_empty(&phb_bus->devices))) {
258 		return -EBUSY;
259 	}
260 
261 	rc = pcibios_remove_root_bus(phb);
262 	if (rc)
263 		return -EIO;
264 
265 	device_unregister(phb_bus->bridge);
266 	pci_remove_bus(phb_bus);
267 
268 	return 0;
269 }
270 
271 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
272 {
273 	struct slot *slot;
274 	struct pci_dn *pdn;
275 	int rc = 0;
276 
277 	if (!rpaphp_find_pci_bus(dn))
278 		return -EINVAL;
279 
280 	slot = find_slot(dn);
281 	if (slot) {
282 		/* Remove hotplug slot */
283 		if (rpaphp_remove_slot(slot)) {
284 			printk(KERN_ERR
285 				"%s: unable to remove hotplug slot %s\n",
286 				__FUNCTION__, drc_name);
287 			return -EIO;
288 		}
289 	}
290 
291 	pdn = dn->data;
292 	BUG_ON(!pdn || !pdn->phb);
293 	rc = dlpar_remove_root_bus(pdn->phb);
294 	if (rc < 0)
295 		return rc;
296 
297 	pdn->phb = NULL;
298 
299 	return 0;
300 }
301 
302 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
303 {
304 	struct pci_controller *phb;
305 
306 	if (PCI_DN(dn)->phb) {
307 		/* PHB already exists */
308 		return -EINVAL;
309 	}
310 
311 	phb = init_phb_dynamic(dn);
312 	if (!phb)
313 		return -EIO;
314 
315 	if (rpaphp_add_slot(dn)) {
316 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
317 			__FUNCTION__, drc_name);
318 		return -EIO;
319 	}
320 	return 0;
321 }
322 
323 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
324 {
325 	if (vio_find_node(dn))
326 		return -EINVAL;
327 
328 	if (!vio_register_device_node(dn)) {
329 		printk(KERN_ERR
330 			"%s: failed to register vio node %s\n",
331 			__FUNCTION__, drc_name);
332 		return -EIO;
333 	}
334 	return 0;
335 }
336 
337 /**
338  * dlpar_add_slot - DLPAR add an I/O Slot
339  * @drc_name: drc-name of newly added slot
340  *
341  * Make the hotplug module and the kernel aware
342  * of a newly added I/O Slot.
343  * Return Codes -
344  * 0			Success
345  * -ENODEV		Not a valid drc_name
346  * -EINVAL		Slot already added
347  * -ERESTARTSYS		Signalled before obtaining lock
348  * -EIO			Internal PCI Error
349  */
350 int dlpar_add_slot(char *drc_name)
351 {
352 	struct device_node *dn = NULL;
353 	int node_type;
354 	int rc = -EIO;
355 
356 	if (down_interruptible(&rpadlpar_sem))
357 		return -ERESTARTSYS;
358 
359 	/* Find newly added node */
360 	dn = find_dlpar_node(drc_name, &node_type);
361 	if (!dn) {
362 		rc = -ENODEV;
363 		goto exit;
364 	}
365 
366 	switch (node_type) {
367 		case NODE_TYPE_VIO:
368 			rc = dlpar_add_vio_slot(drc_name, dn);
369 			break;
370 		case NODE_TYPE_SLOT:
371 			rc = dlpar_add_pci_slot(drc_name, dn);
372 			break;
373 		case NODE_TYPE_PHB:
374 			rc = dlpar_add_phb(drc_name, dn);
375 			break;
376 	}
377 
378 	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
379 exit:
380 	up(&rpadlpar_sem);
381 	return rc;
382 }
383 
384 /**
385  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
386  * @drc_name: drc-name of newly added slot
387  *
388  * Remove the kernel and hotplug representations
389  * of an I/O Slot.
390  * Return Codes:
391  * 0			Success
392  * -EINVAL		Vio dev doesn't exist
393  */
394 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
395 {
396 	struct vio_dev *vio_dev;
397 
398 	vio_dev = vio_find_node(dn);
399 	if (!vio_dev)
400 		return -EINVAL;
401 
402 	vio_unregister_device(vio_dev);
403 	return 0;
404 }
405 
406 /**
407  * dlpar_remove_slot - DLPAR remove a PCI I/O Slot
408  * @drc_name: drc-name of newly added slot
409  *
410  * Remove the kernel and hotplug representations
411  * of a PCI I/O Slot.
412  * Return Codes:
413  * 0			Success
414  * -ENODEV		Not a valid drc_name
415  * -EIO			Internal PCI Error
416  */
417 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
418 {
419 	struct pci_bus *bus;
420 	struct slot *slot;
421 
422 	bus = rpaphp_find_pci_bus(dn);
423 	if (!bus)
424 		return -EINVAL;
425 
426 	slot = find_slot(dn);
427 	if (slot) {
428 		/* Remove hotplug slot */
429 		if (rpaphp_remove_slot(slot)) {
430 			printk(KERN_ERR
431 				"%s: unable to remove hotplug slot %s\n",
432 				__FUNCTION__, drc_name);
433 			return -EIO;
434 		}
435 	}
436 
437 	if (unmap_bus_range(bus)) {
438 		printk(KERN_ERR "%s: failed to unmap bus range\n",
439 			__FUNCTION__);
440 		return -ERANGE;
441 	}
442 
443 	BUG_ON(!bus->self);
444 	pci_remove_bus_device(bus->self);
445 	return 0;
446 }
447 
448 /**
449  * dlpar_remove_slot - DLPAR remove an I/O Slot
450  * @drc_name: drc-name of newly added slot
451  *
452  * Remove the kernel and hotplug representations
453  * of an I/O Slot.
454  * Return Codes:
455  * 0			Success
456  * -ENODEV		Not a valid drc_name
457  * -EINVAL		Slot already removed
458  * -ERESTARTSYS		Signalled before obtaining lock
459  * -EIO			Internal Error
460  */
461 int dlpar_remove_slot(char *drc_name)
462 {
463 	struct device_node *dn;
464 	int node_type;
465 	int rc = 0;
466 
467 	if (down_interruptible(&rpadlpar_sem))
468 		return -ERESTARTSYS;
469 
470 	dn = find_dlpar_node(drc_name, &node_type);
471 	if (!dn) {
472 		rc = -ENODEV;
473 		goto exit;
474 	}
475 
476 	switch (node_type) {
477 		case NODE_TYPE_VIO:
478 			rc = dlpar_remove_vio_slot(drc_name, dn);
479 			break;
480 		case NODE_TYPE_PHB:
481 			rc = dlpar_remove_phb(drc_name, dn);
482 			break;
483 		case NODE_TYPE_SLOT:
484 			rc = dlpar_remove_pci_slot(drc_name, dn);
485 			break;
486 	}
487 	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
488 exit:
489 	up(&rpadlpar_sem);
490 	return rc;
491 }
492 
493 static inline int is_dlpar_capable(void)
494 {
495 	int rc = rtas_token("ibm,configure-connector");
496 
497 	return (int) (rc != RTAS_UNKNOWN_SERVICE);
498 }
499 
500 int __init rpadlpar_io_init(void)
501 {
502 	int rc = 0;
503 
504 	if (!is_dlpar_capable()) {
505 		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
506 			__FUNCTION__);
507 		return -EPERM;
508 	}
509 
510 	rc = dlpar_sysfs_init();
511 	return rc;
512 }
513 
514 void rpadlpar_io_exit(void)
515 {
516 	dlpar_sysfs_exit();
517 	return;
518 }
519 
520 module_init(rpadlpar_io_init);
521 module_exit(rpadlpar_io_exit);
522 MODULE_LICENSE("GPL");
523