xref: /linux/drivers/pci/hotplug/rpadlpar_core.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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 <linux/string.h>
20 
21 #include <asm/pci-bridge.h>
22 #include <asm/semaphore.h>
23 #include <asm/rtas.h>
24 #include <asm/vio.h>
25 
26 #include "../pci.h"
27 #include "rpaphp.h"
28 #include "rpadlpar.h"
29 
30 static DECLARE_MUTEX(rpadlpar_sem);
31 
32 #define DLPAR_MODULE_NAME "rpadlpar_io"
33 
34 #define NODE_TYPE_VIO  1
35 #define NODE_TYPE_SLOT 2
36 #define NODE_TYPE_PHB  3
37 
38 static struct device_node *find_vio_slot_node(char *drc_name)
39 {
40 	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
41 	struct device_node *dn = NULL;
42 	char *name;
43 	int rc;
44 
45 	if (!parent)
46 		return NULL;
47 
48 	while ((dn = of_get_next_child(parent, dn))) {
49 		rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
50 		if ((rc == 0) && (!strcmp(drc_name, name)))
51 			break;
52 	}
53 
54 	return dn;
55 }
56 
57 /* Find dlpar-capable pci node that contains the specified name and type */
58 static struct device_node *find_php_slot_pci_node(char *drc_name,
59 						  char *drc_type)
60 {
61 	struct device_node *np = NULL;
62 	char *name;
63 	char *type;
64 	int rc;
65 
66 	while ((np = of_find_node_by_type(np, "pci"))) {
67 		rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
68 		if (rc == 0)
69 			if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
70 				break;
71 	}
72 
73 	return np;
74 }
75 
76 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
77 {
78 	struct device_node *dn;
79 
80 	dn = find_php_slot_pci_node(drc_name, "SLOT");
81 	if (dn) {
82 		*node_type = NODE_TYPE_SLOT;
83 		return dn;
84 	}
85 
86 	dn = find_php_slot_pci_node(drc_name, "PHB");
87 	if (dn) {
88 		*node_type = NODE_TYPE_PHB;
89 		return dn;
90 	}
91 
92 	dn = find_vio_slot_node(drc_name);
93 	if (dn) {
94 		*node_type = NODE_TYPE_VIO;
95 		return dn;
96 	}
97 
98 	return NULL;
99 }
100 
101 static struct slot *find_slot(struct device_node *dn)
102 {
103 	struct list_head *tmp, *n;
104 	struct slot *slot;
105 
106         list_for_each_safe(tmp, n, &rpaphp_slot_head) {
107                 slot = list_entry(tmp, struct slot, rpaphp_slot_list);
108                 if (slot->dn == dn)
109                         return slot;
110         }
111 
112         return NULL;
113 }
114 
115 static void rpadlpar_claim_one_bus(struct pci_bus *b)
116 {
117 	struct list_head *ld;
118 	struct pci_bus *child_bus;
119 
120 	for (ld = b->devices.next; ld != &b->devices; ld = ld->next) {
121 		struct pci_dev *dev = pci_dev_b(ld);
122 		int i;
123 
124 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
125 			struct resource *r = &dev->resource[i];
126 
127 			if (r->parent || !r->start || !r->flags)
128 				continue;
129 			rpaphp_claim_resource(dev, i);
130 		}
131 	}
132 
133 	list_for_each_entry(child_bus, &b->children, node)
134 		rpadlpar_claim_one_bus(child_bus);
135 }
136 
137 static int pci_add_secondary_bus(struct device_node *dn,
138 		struct pci_dev *bridge_dev)
139 {
140 	struct pci_dn *pdn = dn->data;
141 	struct pci_controller *hose = pdn->phb;
142 	struct pci_bus *child;
143 	u8 sec_busno;
144 
145 	/* Get busno of downstream bus */
146 	pci_read_config_byte(bridge_dev, PCI_SECONDARY_BUS, &sec_busno);
147 
148 	/* Allocate and add to children of bridge_dev->bus */
149 	child = pci_add_new_bus(bridge_dev->bus, bridge_dev, sec_busno);
150 	if (!child) {
151 		printk(KERN_ERR "%s: could not add secondary bus\n", __FUNCTION__);
152 		return -ENOMEM;
153 	}
154 
155 	sprintf(child->name, "PCI Bus #%02x", child->number);
156 
157 	/* Fixup subordinate bridge bases and resources */
158 	pcibios_fixup_bus(child);
159 
160 	/* Claim new bus resources */
161 	rpadlpar_claim_one_bus(bridge_dev->bus);
162 
163 	if (hose->last_busno < child->number)
164 		hose->last_busno = child->number;
165 
166 	pdn->bussubno = child->number;
167 
168 	/* ioremap() for child bus, which may or may not succeed */
169 	remap_bus_range(child);
170 
171 	return 0;
172 }
173 
174 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
175 					struct device_node *dev_dn)
176 {
177 	struct pci_dev *tmp = NULL;
178 	struct device_node *child_dn;
179 
180 	list_for_each_entry(tmp, &parent->devices, bus_list) {
181 		child_dn = pci_device_to_OF_node(tmp);
182 		if (child_dn == dev_dn)
183 			return tmp;
184 	}
185 	return NULL;
186 }
187 
188 static struct pci_dev *dlpar_pci_add_bus(struct device_node *dn)
189 {
190 	struct pci_dn *pdn = dn->data;
191 	struct pci_controller *hose = pdn->phb;
192 	struct pci_dev *dev = NULL;
193 
194 	/* Scan phb bus for EADS device, adding new one to bus->devices */
195 	if (!pci_scan_single_device(hose->bus, pdn->devfn)) {
196 		printk(KERN_ERR "%s: found no device on bus\n", __FUNCTION__);
197 		return NULL;
198 	}
199 
200 	/* Add new devices to global lists.  Register in proc, sysfs. */
201 	pci_bus_add_devices(hose->bus);
202 
203 	/* Confirm new bridge dev was created */
204 	dev = dlpar_find_new_dev(hose->bus, dn);
205 	if (dev) {
206 		if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
207 			printk(KERN_ERR "%s: unexpected header type %d\n",
208 				__FUNCTION__, dev->hdr_type);
209 			return NULL;
210 		}
211 
212 		if (pci_add_secondary_bus(dn, dev))
213 			return NULL;
214 	}
215 
216 	return dev;
217 }
218 
219 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
220 {
221 	struct pci_dev *dev;
222 	int rc;
223 
224 	if (rpaphp_find_pci_bus(dn))
225 		return -EINVAL;
226 
227 	/* Add pci bus */
228 	dev = dlpar_pci_add_bus(dn);
229 	if (!dev) {
230 		printk(KERN_ERR "%s: unable to add bus %s\n", __FUNCTION__,
231 			drc_name);
232 		return -EIO;
233 	}
234 
235 	if (dn->child) {
236 		rc = rpaphp_config_pci_adapter(dev->subordinate);
237 		if (rc < 0) {
238 			printk(KERN_ERR "%s: unable to enable slot %s\n",
239 				__FUNCTION__, drc_name);
240 			return -EIO;
241 		}
242 	}
243 
244 	/* Add hotplug slot */
245 	if (rpaphp_add_slot(dn)) {
246 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
247 			__FUNCTION__, drc_name);
248 		return -EIO;
249 	}
250 	return 0;
251 }
252 
253 static int dlpar_remove_root_bus(struct pci_controller *phb)
254 {
255 	struct pci_bus *phb_bus;
256 	int rc;
257 
258 	phb_bus = phb->bus;
259 	if (!(list_empty(&phb_bus->children) &&
260 	      list_empty(&phb_bus->devices))) {
261 		return -EBUSY;
262 	}
263 
264 	rc = pcibios_remove_root_bus(phb);
265 	if (rc)
266 		return -EIO;
267 
268 	device_unregister(phb_bus->bridge);
269 	pci_remove_bus(phb_bus);
270 
271 	return 0;
272 }
273 
274 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
275 {
276 	struct slot *slot;
277 	struct pci_dn *pdn;
278 	int rc = 0;
279 
280 	if (!rpaphp_find_pci_bus(dn))
281 		return -EINVAL;
282 
283 	slot = find_slot(dn);
284 	if (slot) {
285 		/* Remove hotplug slot */
286 		if (rpaphp_remove_slot(slot)) {
287 			printk(KERN_ERR
288 				"%s: unable to remove hotplug slot %s\n",
289 				__FUNCTION__, drc_name);
290 			return -EIO;
291 		}
292 	}
293 
294 	pdn = dn->data;
295 	BUG_ON(!pdn || !pdn->phb);
296 	rc = dlpar_remove_root_bus(pdn->phb);
297 	if (rc < 0)
298 		return rc;
299 
300 	pdn->phb = NULL;
301 
302 	return 0;
303 }
304 
305 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
306 {
307 	struct pci_controller *phb;
308 
309 	if (PCI_DN(dn)->phb) {
310 		/* PHB already exists */
311 		return -EINVAL;
312 	}
313 
314 	phb = init_phb_dynamic(dn);
315 	if (!phb)
316 		return -EIO;
317 
318 	if (rpaphp_add_slot(dn)) {
319 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
320 			__FUNCTION__, drc_name);
321 		return -EIO;
322 	}
323 	return 0;
324 }
325 
326 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
327 {
328 	if (vio_find_node(dn))
329 		return -EINVAL;
330 
331 	if (!vio_register_device_node(dn)) {
332 		printk(KERN_ERR
333 			"%s: failed to register vio node %s\n",
334 			__FUNCTION__, drc_name);
335 		return -EIO;
336 	}
337 	return 0;
338 }
339 
340 /**
341  * dlpar_add_slot - DLPAR add an I/O Slot
342  * @drc_name: drc-name of newly added slot
343  *
344  * Make the hotplug module and the kernel aware
345  * of a newly added I/O Slot.
346  * Return Codes -
347  * 0			Success
348  * -ENODEV		Not a valid drc_name
349  * -EINVAL		Slot already added
350  * -ERESTARTSYS		Signalled before obtaining lock
351  * -EIO			Internal PCI Error
352  */
353 int dlpar_add_slot(char *drc_name)
354 {
355 	struct device_node *dn = NULL;
356 	int node_type;
357 	int rc = -EIO;
358 
359 	if (down_interruptible(&rpadlpar_sem))
360 		return -ERESTARTSYS;
361 
362 	/* Find newly added node */
363 	dn = find_dlpar_node(drc_name, &node_type);
364 	if (!dn) {
365 		rc = -ENODEV;
366 		goto exit;
367 	}
368 
369 	switch (node_type) {
370 		case NODE_TYPE_VIO:
371 			rc = dlpar_add_vio_slot(drc_name, dn);
372 			break;
373 		case NODE_TYPE_SLOT:
374 			rc = dlpar_add_pci_slot(drc_name, dn);
375 			break;
376 		case NODE_TYPE_PHB:
377 			rc = dlpar_add_phb(drc_name, dn);
378 			break;
379 	}
380 
381 	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
382 exit:
383 	up(&rpadlpar_sem);
384 	return rc;
385 }
386 
387 /**
388  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
389  * @drc_name: drc-name of newly added slot
390  *
391  * Remove the kernel and hotplug representations
392  * of an I/O Slot.
393  * Return Codes:
394  * 0			Success
395  * -EINVAL		Vio dev doesn't exist
396  */
397 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
398 {
399 	struct vio_dev *vio_dev;
400 
401 	vio_dev = vio_find_node(dn);
402 	if (!vio_dev)
403 		return -EINVAL;
404 
405 	vio_unregister_device(vio_dev);
406 	return 0;
407 }
408 
409 /**
410  * dlpar_remove_slot - DLPAR remove a PCI I/O Slot
411  * @drc_name: drc-name of newly added slot
412  *
413  * Remove the kernel and hotplug representations
414  * of a PCI I/O Slot.
415  * Return Codes:
416  * 0			Success
417  * -ENODEV		Not a valid drc_name
418  * -EIO			Internal PCI Error
419  */
420 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
421 {
422 	struct pci_bus *bus;
423 	struct slot *slot;
424 
425 	bus = rpaphp_find_pci_bus(dn);
426 	if (!bus)
427 		return -EINVAL;
428 
429 	slot = find_slot(dn);
430 	if (slot) {
431 		/* Remove hotplug slot */
432 		if (rpaphp_remove_slot(slot)) {
433 			printk(KERN_ERR
434 				"%s: unable to remove hotplug slot %s\n",
435 				__FUNCTION__, drc_name);
436 			return -EIO;
437 		}
438 	}
439 
440 	if (unmap_bus_range(bus)) {
441 		printk(KERN_ERR "%s: failed to unmap bus range\n",
442 			__FUNCTION__);
443 		return -ERANGE;
444 	}
445 
446 	BUG_ON(!bus->self);
447 	pci_remove_bus_device(bus->self);
448 	return 0;
449 }
450 
451 /**
452  * dlpar_remove_slot - DLPAR remove an I/O Slot
453  * @drc_name: drc-name of newly added slot
454  *
455  * Remove the kernel and hotplug representations
456  * of an I/O Slot.
457  * Return Codes:
458  * 0			Success
459  * -ENODEV		Not a valid drc_name
460  * -EINVAL		Slot already removed
461  * -ERESTARTSYS		Signalled before obtaining lock
462  * -EIO			Internal Error
463  */
464 int dlpar_remove_slot(char *drc_name)
465 {
466 	struct device_node *dn;
467 	int node_type;
468 	int rc = 0;
469 
470 	if (down_interruptible(&rpadlpar_sem))
471 		return -ERESTARTSYS;
472 
473 	dn = find_dlpar_node(drc_name, &node_type);
474 	if (!dn) {
475 		rc = -ENODEV;
476 		goto exit;
477 	}
478 
479 	switch (node_type) {
480 		case NODE_TYPE_VIO:
481 			rc = dlpar_remove_vio_slot(drc_name, dn);
482 			break;
483 		case NODE_TYPE_PHB:
484 			rc = dlpar_remove_phb(drc_name, dn);
485 			break;
486 		case NODE_TYPE_SLOT:
487 			rc = dlpar_remove_pci_slot(drc_name, dn);
488 			break;
489 	}
490 	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
491 exit:
492 	up(&rpadlpar_sem);
493 	return rc;
494 }
495 
496 static inline int is_dlpar_capable(void)
497 {
498 	int rc = rtas_token("ibm,configure-connector");
499 
500 	return (int) (rc != RTAS_UNKNOWN_SERVICE);
501 }
502 
503 int __init rpadlpar_io_init(void)
504 {
505 	int rc = 0;
506 
507 	if (!is_dlpar_capable()) {
508 		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
509 			__FUNCTION__);
510 		return -EPERM;
511 	}
512 
513 	rc = dlpar_sysfs_init();
514 	return rc;
515 }
516 
517 void rpadlpar_io_exit(void)
518 {
519 	dlpar_sysfs_exit();
520 	return;
521 }
522 
523 module_init(rpadlpar_io_init);
524 module_exit(rpadlpar_io_exit);
525 MODULE_LICENSE("GPL");
526