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