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 <linux/mutex.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 DEFINE_MUTEX(rpadlpar_mutex);
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_name(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 /**
102  * find_php_slot - return hotplug slot structure for device node
103  * @dn: target &device_node
104  *
105  * This routine will return the hotplug slot structure
106  * for a given device node. Note that built-in PCI slots
107  * may be dlpar-able, but not hot-pluggable, so this routine
108  * will return NULL for built-in PCI slots.
109  */
110 static struct slot *find_php_slot(struct device_node *dn)
111 {
112 	struct list_head *tmp, *n;
113 	struct slot *slot;
114 
115 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
116 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
117 		if (slot->dn == dn)
118 			return slot;
119 	}
120 
121 	return NULL;
122 }
123 
124 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
125 					struct device_node *dev_dn)
126 {
127 	struct pci_dev *tmp = NULL;
128 	struct device_node *child_dn;
129 
130 	list_for_each_entry(tmp, &parent->devices, bus_list) {
131 		child_dn = pci_device_to_OF_node(tmp);
132 		if (child_dn == dev_dn)
133 			return tmp;
134 	}
135 	return NULL;
136 }
137 
138 static void dlpar_pci_add_bus(struct device_node *dn)
139 {
140 	struct pci_dn *pdn = PCI_DN(dn);
141 	struct pci_controller *phb = pdn->phb;
142 	struct pci_dev *dev = NULL;
143 
144 	eeh_add_device_tree_early(dn);
145 
146 	/* Add EADS device to PHB bus, adding new entry to bus->devices */
147 	dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
148 	if (!dev) {
149 		printk(KERN_ERR "%s: failed to create pci dev for %s\n",
150 				__func__, dn->full_name);
151 		return;
152 	}
153 
154 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
155 	    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
156 		of_scan_pci_bridge(dn, dev);
157 
158 	pcibios_fixup_new_pci_devices(dev->subordinate);
159 
160 	/* Claim new bus resources */
161 	pcibios_claim_one_bus(dev->bus);
162 
163 	/* Map IO space for child bus, which may or may not succeed */
164 	pcibios_map_io_space(dev->subordinate);
165 
166 	/* Add new devices to global lists.  Register in proc, sysfs. */
167 	pci_bus_add_devices(phb->bus);
168 }
169 
170 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
171 {
172 	struct pci_dev *dev;
173 	struct pci_controller *phb;
174 
175 	if (pcibios_find_pci_bus(dn))
176 		return -EINVAL;
177 
178 	/* Add pci bus */
179 	dlpar_pci_add_bus(dn);
180 
181 	/* Confirm new bridge dev was created */
182 	phb = PCI_DN(dn)->phb;
183 	dev = dlpar_find_new_dev(phb->bus, dn);
184 
185 	if (!dev) {
186 		printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
187 			drc_name);
188 		return -EIO;
189 	}
190 
191 	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
192 		printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
193 			__func__, dev->hdr_type, drc_name);
194 		return -EIO;
195 	}
196 
197 	/* Add hotplug slot */
198 	if (rpaphp_add_slot(dn)) {
199 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
200 			__func__, drc_name);
201 		return -EIO;
202 	}
203 	return 0;
204 }
205 
206 static int dlpar_remove_root_bus(struct pci_controller *phb)
207 {
208 	struct pci_bus *phb_bus;
209 	int rc;
210 
211 	phb_bus = phb->bus;
212 	if (!(list_empty(&phb_bus->children) &&
213 	      list_empty(&phb_bus->devices))) {
214 		return -EBUSY;
215 	}
216 
217 	rc = pcibios_remove_root_bus(phb);
218 	if (rc)
219 		return -EIO;
220 
221 	device_unregister(phb_bus->bridge);
222 	pci_remove_bus(phb_bus);
223 
224 	return 0;
225 }
226 
227 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
228 {
229 	struct slot *slot;
230 	struct pci_dn *pdn;
231 	int rc = 0;
232 
233 	if (!pcibios_find_pci_bus(dn))
234 		return -EINVAL;
235 
236 	/* If pci slot is hotplugable, use hotplug to remove it */
237 	slot = find_php_slot(dn);
238 	if (slot) {
239 		if (rpaphp_deregister_slot(slot)) {
240 			printk(KERN_ERR
241 				"%s: unable to remove hotplug slot %s\n",
242 				__func__, drc_name);
243 			return -EIO;
244 		}
245 	}
246 
247 	pdn = dn->data;
248 	BUG_ON(!pdn || !pdn->phb);
249 	rc = dlpar_remove_root_bus(pdn->phb);
250 	if (rc < 0)
251 		return rc;
252 
253 	pdn->phb = NULL;
254 
255 	return 0;
256 }
257 
258 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
259 {
260 	struct pci_controller *phb;
261 
262 	if (PCI_DN(dn) && PCI_DN(dn)->phb) {
263 		/* PHB already exists */
264 		return -EINVAL;
265 	}
266 
267 	phb = init_phb_dynamic(dn);
268 	if (!phb)
269 		return -EIO;
270 
271 	if (rpaphp_add_slot(dn)) {
272 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
273 			__func__, drc_name);
274 		return -EIO;
275 	}
276 	return 0;
277 }
278 
279 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
280 {
281 	if (vio_find_node(dn))
282 		return -EINVAL;
283 
284 	if (!vio_register_device_node(dn)) {
285 		printk(KERN_ERR
286 			"%s: failed to register vio node %s\n",
287 			__func__, drc_name);
288 		return -EIO;
289 	}
290 	return 0;
291 }
292 
293 /**
294  * dlpar_add_slot - DLPAR add an I/O Slot
295  * @drc_name: drc-name of newly added slot
296  *
297  * Make the hotplug module and the kernel aware of a newly added I/O Slot.
298  * Return Codes:
299  * 0			Success
300  * -ENODEV		Not a valid drc_name
301  * -EINVAL		Slot already added
302  * -ERESTARTSYS		Signalled before obtaining lock
303  * -EIO			Internal PCI Error
304  */
305 int dlpar_add_slot(char *drc_name)
306 {
307 	struct device_node *dn = NULL;
308 	int node_type;
309 	int rc = -EIO;
310 
311 	if (mutex_lock_interruptible(&rpadlpar_mutex))
312 		return -ERESTARTSYS;
313 
314 	/* Find newly added node */
315 	dn = find_dlpar_node(drc_name, &node_type);
316 	if (!dn) {
317 		rc = -ENODEV;
318 		goto exit;
319 	}
320 
321 	switch (node_type) {
322 		case NODE_TYPE_VIO:
323 			rc = dlpar_add_vio_slot(drc_name, dn);
324 			break;
325 		case NODE_TYPE_SLOT:
326 			rc = dlpar_add_pci_slot(drc_name, dn);
327 			break;
328 		case NODE_TYPE_PHB:
329 			rc = dlpar_add_phb(drc_name, dn);
330 			break;
331 	}
332 
333 	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
334 exit:
335 	mutex_unlock(&rpadlpar_mutex);
336 	return rc;
337 }
338 
339 /**
340  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
341  * @drc_name: drc-name of newly added slot
342  * @dn: &device_node
343  *
344  * Remove the kernel and hotplug representations of an I/O Slot.
345  * Return Codes:
346  * 0			Success
347  * -EINVAL		Vio dev doesn't exist
348  */
349 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
350 {
351 	struct vio_dev *vio_dev;
352 
353 	vio_dev = vio_find_node(dn);
354 	if (!vio_dev)
355 		return -EINVAL;
356 
357 	vio_unregister_device(vio_dev);
358 	return 0;
359 }
360 
361 /**
362  * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
363  * @drc_name: drc-name of newly added slot
364  * @dn: &device_node
365  *
366  * Remove the kernel and hotplug representations of a PCI I/O Slot.
367  * Return Codes:
368  * 0			Success
369  * -ENODEV		Not a valid drc_name
370  * -EIO			Internal PCI Error
371  */
372 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
373 {
374 	struct pci_bus *bus;
375 	struct slot *slot;
376 
377 	bus = pcibios_find_pci_bus(dn);
378 	if (!bus)
379 		return -EINVAL;
380 
381 	/* If pci slot is hotplugable, use hotplug to remove it */
382 	slot = find_php_slot(dn);
383 	if (slot) {
384 		if (rpaphp_deregister_slot(slot)) {
385 			printk(KERN_ERR
386 				"%s: unable to remove hotplug slot %s\n",
387 				__func__, drc_name);
388 			return -EIO;
389 		}
390 	} else
391 		pcibios_remove_pci_devices(bus);
392 
393 	if (pcibios_unmap_io_space(bus)) {
394 		printk(KERN_ERR "%s: failed to unmap bus range\n",
395 			__func__);
396 		return -ERANGE;
397 	}
398 
399 	BUG_ON(!bus->self);
400 	pci_remove_bus_device(bus->self);
401 	return 0;
402 }
403 
404 /**
405  * dlpar_remove_slot - DLPAR remove an I/O Slot
406  * @drc_name: drc-name of newly added slot
407  *
408  * Remove the kernel and hotplug representations of an I/O Slot.
409  * Return Codes:
410  * 0			Success
411  * -ENODEV		Not a valid drc_name
412  * -EINVAL		Slot already removed
413  * -ERESTARTSYS		Signalled before obtaining lock
414  * -EIO			Internal Error
415  */
416 int dlpar_remove_slot(char *drc_name)
417 {
418 	struct device_node *dn;
419 	int node_type;
420 	int rc = 0;
421 
422 	if (mutex_lock_interruptible(&rpadlpar_mutex))
423 		return -ERESTARTSYS;
424 
425 	dn = find_dlpar_node(drc_name, &node_type);
426 	if (!dn) {
427 		rc = -ENODEV;
428 		goto exit;
429 	}
430 
431 	switch (node_type) {
432 		case NODE_TYPE_VIO:
433 			rc = dlpar_remove_vio_slot(drc_name, dn);
434 			break;
435 		case NODE_TYPE_PHB:
436 			rc = dlpar_remove_phb(drc_name, dn);
437 			break;
438 		case NODE_TYPE_SLOT:
439 			rc = dlpar_remove_pci_slot(drc_name, dn);
440 			break;
441 	}
442 	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
443 exit:
444 	mutex_unlock(&rpadlpar_mutex);
445 	return rc;
446 }
447 
448 static inline int is_dlpar_capable(void)
449 {
450 	int rc = rtas_token("ibm,configure-connector");
451 
452 	return (int) (rc != RTAS_UNKNOWN_SERVICE);
453 }
454 
455 int __init rpadlpar_io_init(void)
456 {
457 	int rc = 0;
458 
459 	if (!is_dlpar_capable()) {
460 		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
461 			__func__);
462 		return -EPERM;
463 	}
464 
465 	rc = dlpar_sysfs_init();
466 	return rc;
467 }
468 
469 void rpadlpar_io_exit(void)
470 {
471 	dlpar_sysfs_exit();
472 	return;
473 }
474 
475 module_init(rpadlpar_io_init);
476 module_exit(rpadlpar_io_exit);
477 MODULE_LICENSE("GPL");
478