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/module.h>
22#include <linux/pci.h>
23#include <linux/string.h>
24#include <linux/vmalloc.h>
25
26#include <asm/pci-bridge.h>
27#include <linux/mutex.h>
28#include <asm/rtas.h>
29#include <asm/vio.h>
30
31#include "../pci.h"
32#include "rpaphp.h"
33#include "rpadlpar.h"
34
35static DEFINE_MUTEX(rpadlpar_mutex);
36
37#define DLPAR_MODULE_NAME "rpadlpar_io"
38
39#define NODE_TYPE_VIO  1
40#define NODE_TYPE_SLOT 2
41#define NODE_TYPE_PHB  3
42
43static struct device_node *find_vio_slot_node(char *drc_name)
44{
45	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
46	struct device_node *dn = NULL;
47	char *name;
48	int rc;
49
50	if (!parent)
51		return NULL;
52
53	while ((dn = of_get_next_child(parent, dn))) {
54		rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
55		if ((rc == 0) && (!strcmp(drc_name, name)))
56			break;
57	}
58
59	return dn;
60}
61
62/* Find dlpar-capable pci node that contains the specified name and type */
63static struct device_node *find_php_slot_pci_node(char *drc_name,
64						  char *drc_type)
65{
66	struct device_node *np = NULL;
67	char *name;
68	char *type;
69	int rc;
70
71	while ((np = of_find_node_by_name(np, "pci"))) {
72		rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
73		if (rc == 0)
74			if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
75				break;
76	}
77
78	return np;
79}
80
81static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
82{
83	struct device_node *dn;
84
85	dn = find_php_slot_pci_node(drc_name, "SLOT");
86	if (dn) {
87		*node_type = NODE_TYPE_SLOT;
88		return dn;
89	}
90
91	dn = find_php_slot_pci_node(drc_name, "PHB");
92	if (dn) {
93		*node_type = NODE_TYPE_PHB;
94		return dn;
95	}
96
97	dn = find_vio_slot_node(drc_name);
98	if (dn) {
99		*node_type = NODE_TYPE_VIO;
100		return dn;
101	}
102
103	return NULL;
104}
105
106/**
107 * find_php_slot - return hotplug slot structure for device node
108 * @dn: target &device_node
109 *
110 * This routine will return the hotplug slot structure
111 * for a given device node. Note that built-in PCI slots
112 * may be dlpar-able, but not hot-pluggable, so this routine
113 * will return NULL for built-in PCI slots.
114 */
115static struct slot *find_php_slot(struct device_node *dn)
116{
117	struct list_head *tmp, *n;
118	struct slot *slot;
119
120	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
121		slot = list_entry(tmp, struct slot, rpaphp_slot_list);
122		if (slot->dn == dn)
123			return slot;
124	}
125
126	return NULL;
127}
128
129static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
130					struct device_node *dev_dn)
131{
132	struct pci_dev *tmp = NULL;
133	struct device_node *child_dn;
134
135	list_for_each_entry(tmp, &parent->devices, bus_list) {
136		child_dn = pci_device_to_OF_node(tmp);
137		if (child_dn == dev_dn)
138			return tmp;
139	}
140	return NULL;
141}
142
143static void dlpar_pci_add_bus(struct device_node *dn)
144{
145	struct pci_dn *pdn = PCI_DN(dn);
146	struct pci_controller *phb = pdn->phb;
147	struct pci_dev *dev = NULL;
148
149	eeh_add_device_tree_early(dn);
150
151	/* Add EADS device to PHB bus, adding new entry to bus->devices */
152	dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
153	if (!dev) {
154		printk(KERN_ERR "%s: failed to create pci dev for %s\n",
155				__func__, dn->full_name);
156		return;
157	}
158
159	/* Scan below the new bridge */
160	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
161	    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
162		of_scan_pci_bridge(dev);
163
164	/* Map IO space for child bus, which may or may not succeed */
165	pcibios_map_io_space(dev->subordinate);
166
167	/* Finish adding it : resource allocation, adding devices, etc...
168	 * Note that we need to perform the finish pass on the -parent-
169	 * bus of the EADS bridge so the bridge device itself gets
170	 * properly added
171	 */
172	pcibios_finish_adding_to_bus(phb->bus);
173}
174
175static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
176{
177	struct pci_dev *dev;
178	struct pci_controller *phb;
179
180	if (pcibios_find_pci_bus(dn))
181		return -EINVAL;
182
183	/* Add pci bus */
184	dlpar_pci_add_bus(dn);
185
186	/* Confirm new bridge dev was created */
187	phb = PCI_DN(dn)->phb;
188	dev = dlpar_find_new_dev(phb->bus, dn);
189
190	if (!dev) {
191		printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
192			drc_name);
193		return -EIO;
194	}
195
196	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
197		printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
198			__func__, dev->hdr_type, drc_name);
199		return -EIO;
200	}
201
202	/* Add hotplug slot */
203	if (rpaphp_add_slot(dn)) {
204		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
205			__func__, drc_name);
206		return -EIO;
207	}
208	return 0;
209}
210
211static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
212{
213	struct slot *slot;
214	struct pci_dn *pdn;
215	int rc = 0;
216
217	if (!pcibios_find_pci_bus(dn))
218		return -EINVAL;
219
220	/* If pci slot is hotplugable, use hotplug to remove it */
221	slot = find_php_slot(dn);
222	if (slot && rpaphp_deregister_slot(slot)) {
223		printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
224		       __func__, drc_name);
225		return -EIO;
226	}
227
228	pdn = dn->data;
229	BUG_ON(!pdn || !pdn->phb);
230	rc = remove_phb_dynamic(pdn->phb);
231	if (rc < 0)
232		return rc;
233
234	pdn->phb = NULL;
235
236	return 0;
237}
238
239static int dlpar_add_phb(char *drc_name, struct device_node *dn)
240{
241	struct pci_controller *phb;
242
243	if (PCI_DN(dn) && PCI_DN(dn)->phb) {
244		/* PHB already exists */
245		return -EINVAL;
246	}
247
248	phb = init_phb_dynamic(dn);
249	if (!phb)
250		return -EIO;
251
252	if (rpaphp_add_slot(dn)) {
253		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
254			__func__, drc_name);
255		return -EIO;
256	}
257	return 0;
258}
259
260static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
261{
262	if (vio_find_node(dn))
263		return -EINVAL;
264
265	if (!vio_register_device_node(dn)) {
266		printk(KERN_ERR
267			"%s: failed to register vio node %s\n",
268			__func__, drc_name);
269		return -EIO;
270	}
271	return 0;
272}
273
274/**
275 * dlpar_add_slot - DLPAR add an I/O Slot
276 * @drc_name: drc-name of newly added slot
277 *
278 * Make the hotplug module and the kernel aware of a newly added I/O Slot.
279 * Return Codes:
280 * 0			Success
281 * -ENODEV		Not a valid drc_name
282 * -EINVAL		Slot already added
283 * -ERESTARTSYS		Signalled before obtaining lock
284 * -EIO			Internal PCI Error
285 */
286int dlpar_add_slot(char *drc_name)
287{
288	struct device_node *dn = NULL;
289	int node_type;
290	int rc = -EIO;
291
292	if (mutex_lock_interruptible(&rpadlpar_mutex))
293		return -ERESTARTSYS;
294
295	/* Find newly added node */
296	dn = find_dlpar_node(drc_name, &node_type);
297	if (!dn) {
298		rc = -ENODEV;
299		goto exit;
300	}
301
302	switch (node_type) {
303		case NODE_TYPE_VIO:
304			rc = dlpar_add_vio_slot(drc_name, dn);
305			break;
306		case NODE_TYPE_SLOT:
307			rc = dlpar_add_pci_slot(drc_name, dn);
308			break;
309		case NODE_TYPE_PHB:
310			rc = dlpar_add_phb(drc_name, dn);
311			break;
312	}
313
314	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
315exit:
316	mutex_unlock(&rpadlpar_mutex);
317	return rc;
318}
319
320/**
321 * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
322 * @drc_name: drc-name of newly added slot
323 * @dn: &device_node
324 *
325 * Remove the kernel and hotplug representations of an I/O Slot.
326 * Return Codes:
327 * 0			Success
328 * -EINVAL		Vio dev doesn't exist
329 */
330static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
331{
332	struct vio_dev *vio_dev;
333
334	vio_dev = vio_find_node(dn);
335	if (!vio_dev)
336		return -EINVAL;
337
338	vio_unregister_device(vio_dev);
339	return 0;
340}
341
342/**
343 * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
344 * @drc_name: drc-name of newly added slot
345 * @dn: &device_node
346 *
347 * Remove the kernel and hotplug representations of a PCI I/O Slot.
348 * Return Codes:
349 * 0			Success
350 * -ENODEV		Not a valid drc_name
351 * -EIO			Internal PCI Error
352 */
353int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
354{
355	struct pci_bus *bus;
356	struct slot *slot;
357
358	bus = pcibios_find_pci_bus(dn);
359	if (!bus)
360		return -EINVAL;
361
362	pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
363		 bus->self ? pci_name(bus->self) : "<!PHB!>");
364
365	slot = find_php_slot(dn);
366	if (slot) {
367		pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
368			 pci_domain_nr(bus), bus->number);
369
370		if (rpaphp_deregister_slot(slot)) {
371			printk(KERN_ERR
372				"%s: unable to remove hotplug slot %s\n",
373				__func__, drc_name);
374			return -EIO;
375		}
376	}
377
378	/* Remove all devices below slot */
379	pcibios_remove_pci_devices(bus);
380
381	/* Unmap PCI IO space */
382	if (pcibios_unmap_io_space(bus)) {
383		printk(KERN_ERR "%s: failed to unmap bus range\n",
384			__func__);
385		return -ERANGE;
386	}
387
388	/* Remove the EADS bridge device itself */
389	BUG_ON(!bus->self);
390	pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
391	eeh_remove_bus_device(bus->self);
392	pci_stop_and_remove_bus_device(bus->self);
393
394	return 0;
395}
396
397/**
398 * dlpar_remove_slot - DLPAR remove an I/O Slot
399 * @drc_name: drc-name of newly added slot
400 *
401 * Remove the kernel and hotplug representations of an I/O Slot.
402 * Return Codes:
403 * 0			Success
404 * -ENODEV		Not a valid drc_name
405 * -EINVAL		Slot already removed
406 * -ERESTARTSYS		Signalled before obtaining lock
407 * -EIO			Internal Error
408 */
409int dlpar_remove_slot(char *drc_name)
410{
411	struct device_node *dn;
412	int node_type;
413	int rc = 0;
414
415	if (mutex_lock_interruptible(&rpadlpar_mutex))
416		return -ERESTARTSYS;
417
418	dn = find_dlpar_node(drc_name, &node_type);
419	if (!dn) {
420		rc = -ENODEV;
421		goto exit;
422	}
423
424	switch (node_type) {
425		case NODE_TYPE_VIO:
426			rc = dlpar_remove_vio_slot(drc_name, dn);
427			break;
428		case NODE_TYPE_PHB:
429			rc = dlpar_remove_phb(drc_name, dn);
430			break;
431		case NODE_TYPE_SLOT:
432			rc = dlpar_remove_pci_slot(drc_name, dn);
433			break;
434	}
435	vm_unmap_aliases();
436
437	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
438exit:
439	mutex_unlock(&rpadlpar_mutex);
440	return rc;
441}
442
443static inline int is_dlpar_capable(void)
444{
445	int rc = rtas_token("ibm,configure-connector");
446
447	return (int) (rc != RTAS_UNKNOWN_SERVICE);
448}
449
450int __init rpadlpar_io_init(void)
451{
452	int rc = 0;
453
454	if (!is_dlpar_capable()) {
455		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
456			__func__);
457		return -EPERM;
458	}
459
460	rc = dlpar_sysfs_init();
461	return rc;
462}
463
464void rpadlpar_io_exit(void)
465{
466	dlpar_sysfs_exit();
467	return;
468}
469
470module_init(rpadlpar_io_init);
471module_exit(rpadlpar_io_exit);
472MODULE_LICENSE("GPL");
473