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 
18 #undef DEBUG
19 
20 #include <linux/init.h>
21 #include <linux/pci.h>
22 #include <linux/string.h>
23 
24 #include <asm/pci-bridge.h>
25 #include <linux/mutex.h>
26 #include <asm/rtas.h>
27 #include <asm/vio.h>
28 
29 #include "../pci.h"
30 #include "rpaphp.h"
31 #include "rpadlpar.h"
32 
33 static DEFINE_MUTEX(rpadlpar_mutex);
34 
35 #define DLPAR_MODULE_NAME "rpadlpar_io"
36 
37 #define NODE_TYPE_VIO  1
38 #define NODE_TYPE_SLOT 2
39 #define NODE_TYPE_PHB  3
40 
41 static struct device_node *find_vio_slot_node(char *drc_name)
42 {
43 	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
44 	struct device_node *dn = NULL;
45 	char *name;
46 	int rc;
47 
48 	if (!parent)
49 		return NULL;
50 
51 	while ((dn = of_get_next_child(parent, dn))) {
52 		rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
53 		if ((rc == 0) && (!strcmp(drc_name, name)))
54 			break;
55 	}
56 
57 	return dn;
58 }
59 
60 /* Find dlpar-capable pci node that contains the specified name and type */
61 static struct device_node *find_php_slot_pci_node(char *drc_name,
62 						  char *drc_type)
63 {
64 	struct device_node *np = NULL;
65 	char *name;
66 	char *type;
67 	int rc;
68 
69 	while ((np = of_find_node_by_name(np, "pci"))) {
70 		rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
71 		if (rc == 0)
72 			if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
73 				break;
74 	}
75 
76 	return np;
77 }
78 
79 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
80 {
81 	struct device_node *dn;
82 
83 	dn = find_php_slot_pci_node(drc_name, "SLOT");
84 	if (dn) {
85 		*node_type = NODE_TYPE_SLOT;
86 		return dn;
87 	}
88 
89 	dn = find_php_slot_pci_node(drc_name, "PHB");
90 	if (dn) {
91 		*node_type = NODE_TYPE_PHB;
92 		return dn;
93 	}
94 
95 	dn = find_vio_slot_node(drc_name);
96 	if (dn) {
97 		*node_type = NODE_TYPE_VIO;
98 		return dn;
99 	}
100 
101 	return NULL;
102 }
103 
104 /**
105  * find_php_slot - return hotplug slot structure for device node
106  * @dn: target &device_node
107  *
108  * This routine will return the hotplug slot structure
109  * for a given device node. Note that built-in PCI slots
110  * may be dlpar-able, but not hot-pluggable, so this routine
111  * will return NULL for built-in PCI slots.
112  */
113 static struct slot *find_php_slot(struct device_node *dn)
114 {
115 	struct list_head *tmp, *n;
116 	struct slot *slot;
117 
118 	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
119 		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
120 		if (slot->dn == dn)
121 			return slot;
122 	}
123 
124 	return NULL;
125 }
126 
127 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
128 					struct device_node *dev_dn)
129 {
130 	struct pci_dev *tmp = NULL;
131 	struct device_node *child_dn;
132 
133 	list_for_each_entry(tmp, &parent->devices, bus_list) {
134 		child_dn = pci_device_to_OF_node(tmp);
135 		if (child_dn == dev_dn)
136 			return tmp;
137 	}
138 	return NULL;
139 }
140 
141 static void dlpar_pci_add_bus(struct device_node *dn)
142 {
143 	struct pci_dn *pdn = PCI_DN(dn);
144 	struct pci_controller *phb = pdn->phb;
145 	struct pci_dev *dev = NULL;
146 
147 	eeh_add_device_tree_early(dn);
148 
149 	/* Add EADS device to PHB bus, adding new entry to bus->devices */
150 	dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
151 	if (!dev) {
152 		printk(KERN_ERR "%s: failed to create pci dev for %s\n",
153 				__func__, dn->full_name);
154 		return;
155 	}
156 
157 	/* Scan below the new bridge */
158 	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
159 	    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
160 		of_scan_pci_bridge(dn, dev);
161 
162 	/* Map IO space for child bus, which may or may not succeed */
163 	pcibios_map_io_space(dev->subordinate);
164 
165 	/* Finish adding it : resource allocation, adding devices, etc...
166 	 * Note that we need to perform the finish pass on the -parent-
167 	 * bus of the EADS bridge so the bridge device itself gets
168 	 * properly added
169 	 */
170 	pcibios_finish_adding_to_bus(phb->bus);
171 }
172 
173 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
174 {
175 	struct pci_dev *dev;
176 	struct pci_controller *phb;
177 
178 	if (pcibios_find_pci_bus(dn))
179 		return -EINVAL;
180 
181 	/* Add pci bus */
182 	dlpar_pci_add_bus(dn);
183 
184 	/* Confirm new bridge dev was created */
185 	phb = PCI_DN(dn)->phb;
186 	dev = dlpar_find_new_dev(phb->bus, dn);
187 
188 	if (!dev) {
189 		printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
190 			drc_name);
191 		return -EIO;
192 	}
193 
194 	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
195 		printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
196 			__func__, dev->hdr_type, drc_name);
197 		return -EIO;
198 	}
199 
200 	/* Add hotplug slot */
201 	if (rpaphp_add_slot(dn)) {
202 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
203 			__func__, drc_name);
204 		return -EIO;
205 	}
206 	return 0;
207 }
208 
209 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
210 {
211 	struct slot *slot;
212 	struct pci_dn *pdn;
213 	int rc = 0;
214 
215 	if (!pcibios_find_pci_bus(dn))
216 		return -EINVAL;
217 
218 	/* If pci slot is hotplugable, use hotplug to remove it */
219 	slot = find_php_slot(dn);
220 	if (slot && rpaphp_deregister_slot(slot)) {
221 		printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
222 		       __func__, drc_name);
223 		return -EIO;
224 	}
225 
226 	pdn = dn->data;
227 	BUG_ON(!pdn || !pdn->phb);
228 	rc = remove_phb_dynamic(pdn->phb);
229 	if (rc < 0)
230 		return rc;
231 
232 	pdn->phb = NULL;
233 
234 	return 0;
235 }
236 
237 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
238 {
239 	struct pci_controller *phb;
240 
241 	if (PCI_DN(dn) && PCI_DN(dn)->phb) {
242 		/* PHB already exists */
243 		return -EINVAL;
244 	}
245 
246 	phb = init_phb_dynamic(dn);
247 	if (!phb)
248 		return -EIO;
249 
250 	if (rpaphp_add_slot(dn)) {
251 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
252 			__func__, drc_name);
253 		return -EIO;
254 	}
255 	return 0;
256 }
257 
258 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
259 {
260 	if (vio_find_node(dn))
261 		return -EINVAL;
262 
263 	if (!vio_register_device_node(dn)) {
264 		printk(KERN_ERR
265 			"%s: failed to register vio node %s\n",
266 			__func__, drc_name);
267 		return -EIO;
268 	}
269 	return 0;
270 }
271 
272 /**
273  * dlpar_add_slot - DLPAR add an I/O Slot
274  * @drc_name: drc-name of newly added slot
275  *
276  * Make the hotplug module and the kernel aware of a newly added I/O Slot.
277  * Return Codes:
278  * 0			Success
279  * -ENODEV		Not a valid drc_name
280  * -EINVAL		Slot already added
281  * -ERESTARTSYS		Signalled before obtaining lock
282  * -EIO			Internal PCI Error
283  */
284 int dlpar_add_slot(char *drc_name)
285 {
286 	struct device_node *dn = NULL;
287 	int node_type;
288 	int rc = -EIO;
289 
290 	if (mutex_lock_interruptible(&rpadlpar_mutex))
291 		return -ERESTARTSYS;
292 
293 	/* Find newly added node */
294 	dn = find_dlpar_node(drc_name, &node_type);
295 	if (!dn) {
296 		rc = -ENODEV;
297 		goto exit;
298 	}
299 
300 	switch (node_type) {
301 		case NODE_TYPE_VIO:
302 			rc = dlpar_add_vio_slot(drc_name, dn);
303 			break;
304 		case NODE_TYPE_SLOT:
305 			rc = dlpar_add_pci_slot(drc_name, dn);
306 			break;
307 		case NODE_TYPE_PHB:
308 			rc = dlpar_add_phb(drc_name, dn);
309 			break;
310 	}
311 
312 	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
313 exit:
314 	mutex_unlock(&rpadlpar_mutex);
315 	return rc;
316 }
317 
318 /**
319  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
320  * @drc_name: drc-name of newly added slot
321  * @dn: &device_node
322  *
323  * Remove the kernel and hotplug representations of an I/O Slot.
324  * Return Codes:
325  * 0			Success
326  * -EINVAL		Vio dev doesn't exist
327  */
328 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
329 {
330 	struct vio_dev *vio_dev;
331 
332 	vio_dev = vio_find_node(dn);
333 	if (!vio_dev)
334 		return -EINVAL;
335 
336 	vio_unregister_device(vio_dev);
337 	return 0;
338 }
339 
340 /**
341  * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
342  * @drc_name: drc-name of newly added slot
343  * @dn: &device_node
344  *
345  * Remove the kernel and hotplug representations of a PCI I/O Slot.
346  * Return Codes:
347  * 0			Success
348  * -ENODEV		Not a valid drc_name
349  * -EIO			Internal PCI Error
350  */
351 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
352 {
353 	struct pci_bus *bus;
354 	struct slot *slot;
355 
356 	bus = pcibios_find_pci_bus(dn);
357 	if (!bus)
358 		return -EINVAL;
359 
360 	pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
361 		 bus->self ? pci_name(bus->self) : "<!PHB!>");
362 
363 	slot = find_php_slot(dn);
364 	if (slot) {
365 		pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
366 			 pci_domain_nr(bus), bus->number);
367 
368 		if (rpaphp_deregister_slot(slot)) {
369 			printk(KERN_ERR
370 				"%s: unable to remove hotplug slot %s\n",
371 				__func__, drc_name);
372 			return -EIO;
373 		}
374 	}
375 
376 	/* Remove all devices below slot */
377 	pcibios_remove_pci_devices(bus);
378 
379 	/* Unmap PCI IO space */
380 	if (pcibios_unmap_io_space(bus)) {
381 		printk(KERN_ERR "%s: failed to unmap bus range\n",
382 			__func__);
383 		return -ERANGE;
384 	}
385 
386 	/* Remove the EADS bridge device itself */
387 	BUG_ON(!bus->self);
388 	pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
389 	eeh_remove_bus_device(bus->self);
390 	pci_remove_bus_device(bus->self);
391 
392 	return 0;
393 }
394 
395 /**
396  * dlpar_remove_slot - DLPAR remove an I/O Slot
397  * @drc_name: drc-name of newly added slot
398  *
399  * Remove the kernel and hotplug representations of an I/O Slot.
400  * Return Codes:
401  * 0			Success
402  * -ENODEV		Not a valid drc_name
403  * -EINVAL		Slot already removed
404  * -ERESTARTSYS		Signalled before obtaining lock
405  * -EIO			Internal Error
406  */
407 int dlpar_remove_slot(char *drc_name)
408 {
409 	struct device_node *dn;
410 	int node_type;
411 	int rc = 0;
412 
413 	if (mutex_lock_interruptible(&rpadlpar_mutex))
414 		return -ERESTARTSYS;
415 
416 	dn = find_dlpar_node(drc_name, &node_type);
417 	if (!dn) {
418 		rc = -ENODEV;
419 		goto exit;
420 	}
421 
422 	switch (node_type) {
423 		case NODE_TYPE_VIO:
424 			rc = dlpar_remove_vio_slot(drc_name, dn);
425 			break;
426 		case NODE_TYPE_PHB:
427 			rc = dlpar_remove_phb(drc_name, dn);
428 			break;
429 		case NODE_TYPE_SLOT:
430 			rc = dlpar_remove_pci_slot(drc_name, dn);
431 			break;
432 	}
433 	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
434 exit:
435 	mutex_unlock(&rpadlpar_mutex);
436 	return rc;
437 }
438 
439 static inline int is_dlpar_capable(void)
440 {
441 	int rc = rtas_token("ibm,configure-connector");
442 
443 	return (int) (rc != RTAS_UNKNOWN_SERVICE);
444 }
445 
446 int __init rpadlpar_io_init(void)
447 {
448 	int rc = 0;
449 
450 	if (!is_dlpar_capable()) {
451 		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
452 			__func__);
453 		return -EPERM;
454 	}
455 
456 	rc = dlpar_sysfs_init();
457 	return rc;
458 }
459 
460 void rpadlpar_io_exit(void)
461 {
462 	dlpar_sysfs_exit();
463 	return;
464 }
465 
466 module_init(rpadlpar_io_init);
467 module_exit(rpadlpar_io_exit);
468 MODULE_LICENSE("GPL");
469