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(pdn);
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 (pci_is_bridge(dev))
161		of_scan_pci_bridge(dev);
162
163	/* Map IO space for child bus, which may or may not succeed */
164	pcibios_map_io_space(dev->subordinate);
165
166	/* Finish adding it : resource allocation, adding devices, etc...
167	 * Note that we need to perform the finish pass on the -parent-
168	 * bus of the EADS bridge so the bridge device itself gets
169	 * properly added
170	 */
171	pcibios_finish_adding_to_bus(phb->bus);
172}
173
174static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
175{
176	struct pci_dev *dev;
177	struct pci_controller *phb;
178
179	if (pcibios_find_pci_bus(dn))
180		return -EINVAL;
181
182	/* Add pci bus */
183	dlpar_pci_add_bus(dn);
184
185	/* Confirm new bridge dev was created */
186	phb = PCI_DN(dn)->phb;
187	dev = dlpar_find_new_dev(phb->bus, dn);
188
189	if (!dev) {
190		printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
191			drc_name);
192		return -EIO;
193	}
194
195	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
196		printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
197			__func__, dev->hdr_type, drc_name);
198		return -EIO;
199	}
200
201	/* Add hotplug slot */
202	if (rpaphp_add_slot(dn)) {
203		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
204			__func__, drc_name);
205		return -EIO;
206	}
207	return 0;
208}
209
210static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
211{
212	struct slot *slot;
213	struct pci_dn *pdn;
214	int rc = 0;
215
216	if (!pcibios_find_pci_bus(dn))
217		return -EINVAL;
218
219	/* If pci slot is hotpluggable, use hotplug to remove it */
220	slot = find_php_slot(dn);
221	if (slot && rpaphp_deregister_slot(slot)) {
222		printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
223		       __func__, drc_name);
224		return -EIO;
225	}
226
227	pdn = dn->data;
228	BUG_ON(!pdn || !pdn->phb);
229	rc = remove_phb_dynamic(pdn->phb);
230	if (rc < 0)
231		return rc;
232
233	pdn->phb = NULL;
234
235	return 0;
236}
237
238static int dlpar_add_phb(char *drc_name, struct device_node *dn)
239{
240	struct pci_controller *phb;
241
242	if (PCI_DN(dn) && PCI_DN(dn)->phb) {
243		/* PHB already exists */
244		return -EINVAL;
245	}
246
247	phb = init_phb_dynamic(dn);
248	if (!phb)
249		return -EIO;
250
251	if (rpaphp_add_slot(dn)) {
252		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
253			__func__, drc_name);
254		return -EIO;
255	}
256	return 0;
257}
258
259static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
260{
261	if (vio_find_node(dn))
262		return -EINVAL;
263
264	if (!vio_register_device_node(dn)) {
265		printk(KERN_ERR
266			"%s: failed to register vio node %s\n",
267			__func__, drc_name);
268		return -EIO;
269	}
270	return 0;
271}
272
273/**
274 * dlpar_add_slot - DLPAR add an I/O Slot
275 * @drc_name: drc-name of newly added slot
276 *
277 * Make the hotplug module and the kernel aware of a newly added I/O Slot.
278 * Return Codes:
279 * 0			Success
280 * -ENODEV		Not a valid drc_name
281 * -EINVAL		Slot already added
282 * -ERESTARTSYS		Signalled before obtaining lock
283 * -EIO			Internal PCI Error
284 */
285int dlpar_add_slot(char *drc_name)
286{
287	struct device_node *dn = NULL;
288	int node_type;
289	int rc = -EIO;
290
291	if (mutex_lock_interruptible(&rpadlpar_mutex))
292		return -ERESTARTSYS;
293
294	/* Find newly added node */
295	dn = find_dlpar_node(drc_name, &node_type);
296	if (!dn) {
297		rc = -ENODEV;
298		goto exit;
299	}
300
301	switch (node_type) {
302		case NODE_TYPE_VIO:
303			rc = dlpar_add_vio_slot(drc_name, dn);
304			break;
305		case NODE_TYPE_SLOT:
306			rc = dlpar_add_pci_slot(drc_name, dn);
307			break;
308		case NODE_TYPE_PHB:
309			rc = dlpar_add_phb(drc_name, dn);
310			break;
311	}
312
313	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
314exit:
315	mutex_unlock(&rpadlpar_mutex);
316	return rc;
317}
318
319/**
320 * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
321 * @drc_name: drc-name of newly added slot
322 * @dn: &device_node
323 *
324 * Remove the kernel and hotplug representations of an I/O Slot.
325 * Return Codes:
326 * 0			Success
327 * -EINVAL		Vio dev doesn't exist
328 */
329static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
330{
331	struct vio_dev *vio_dev;
332
333	vio_dev = vio_find_node(dn);
334	if (!vio_dev)
335		return -EINVAL;
336
337	vio_unregister_device(vio_dev);
338	return 0;
339}
340
341/**
342 * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
343 * @drc_name: drc-name of newly added slot
344 * @dn: &device_node
345 *
346 * Remove the kernel and hotplug representations of a PCI I/O Slot.
347 * Return Codes:
348 * 0			Success
349 * -ENODEV		Not a valid drc_name
350 * -EIO			Internal PCI Error
351 */
352int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
353{
354	struct pci_bus *bus;
355	struct slot *slot;
356	int ret = 0;
357
358	pci_lock_rescan_remove();
359
360	bus = pcibios_find_pci_bus(dn);
361	if (!bus) {
362		ret = -EINVAL;
363		goto out;
364	}
365
366	pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
367		 bus->self ? pci_name(bus->self) : "<!PHB!>");
368
369	slot = find_php_slot(dn);
370	if (slot) {
371		pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
372			 pci_domain_nr(bus), bus->number);
373
374		if (rpaphp_deregister_slot(slot)) {
375			printk(KERN_ERR
376				"%s: unable to remove hotplug slot %s\n",
377				__func__, drc_name);
378			ret = -EIO;
379			goto out;
380		}
381	}
382
383	/* Remove all devices below slot */
384	pcibios_remove_pci_devices(bus);
385
386	/* Unmap PCI IO space */
387	if (pcibios_unmap_io_space(bus)) {
388		printk(KERN_ERR "%s: failed to unmap bus range\n",
389			__func__);
390		ret = -ERANGE;
391		goto out;
392	}
393
394	/* Remove the EADS bridge device itself */
395	BUG_ON(!bus->self);
396	pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
397	pci_stop_and_remove_bus_device(bus->self);
398
399 out:
400	pci_unlock_rescan_remove();
401	return ret;
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 */
416int 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	vm_unmap_aliases();
443
444	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
445exit:
446	mutex_unlock(&rpadlpar_mutex);
447	return rc;
448}
449
450static inline int is_dlpar_capable(void)
451{
452	int rc = rtas_token("ibm,configure-connector");
453
454	return (int) (rc != RTAS_UNKNOWN_SERVICE);
455}
456
457int __init rpadlpar_io_init(void)
458{
459	int rc = 0;
460
461	if (!is_dlpar_capable()) {
462		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
463			__func__);
464		return -EPERM;
465	}
466
467	rc = dlpar_sysfs_init();
468	return rc;
469}
470
471void rpadlpar_io_exit(void)
472{
473	dlpar_sysfs_exit();
474	return;
475}
476
477module_init(rpadlpar_io_init);
478module_exit(rpadlpar_io_exit);
479MODULE_LICENSE("GPL");
480