1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Interface for Dynamic Logical Partitioning of I/O Slots on
4 * RPA-compliant PPC64 platform.
5 *
6 * John Rose <johnrose@austin.ibm.com>
7 * Linda Xie <lxie@us.ibm.com>
8 *
9 * October 2003
10 *
11 * Copyright (C) 2003 IBM.
12 */
13
14 #undef DEBUG
15
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/pci.h>
20 #include <linux/string.h>
21 #include <linux/vmalloc.h>
22
23 #include <asm/pci-bridge.h>
24 #include <linux/mutex.h>
25 #include <asm/rtas.h>
26 #include <asm/vio.h>
27 #include <linux/firmware.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
find_vio_slot_node(char * drc_name)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;
45 int rc;
46
47 if (!parent)
48 return NULL;
49
50 for_each_child_of_node(parent, dn) {
51 rc = rpaphp_check_drc_props(dn, drc_name, NULL);
52 if (rc == 0)
53 break;
54 }
55 of_node_put(parent);
56
57 return dn;
58 }
59
60 /* Find dlpar-capable pci node that contains the specified name and type */
find_php_slot_pci_node(char * drc_name,char * drc_type)61 static struct device_node *find_php_slot_pci_node(char *drc_name,
62 char *drc_type)
63 {
64 struct device_node *np;
65 int rc;
66
67 for_each_node_by_name(np, "pci") {
68 rc = rpaphp_check_drc_props(np, drc_name, drc_type);
69 if (rc == 0)
70 break;
71 }
72
73 return np;
74 }
75
76 /* Returns a device_node with its reference count incremented */
find_dlpar_node(char * drc_name,int * node_type)77 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
78 {
79 struct device_node *dn;
80
81 dn = find_php_slot_pci_node(drc_name, "SLOT");
82 if (dn) {
83 *node_type = NODE_TYPE_SLOT;
84 return dn;
85 }
86
87 dn = find_php_slot_pci_node(drc_name, "PHB");
88 if (dn) {
89 *node_type = NODE_TYPE_PHB;
90 return dn;
91 }
92
93 dn = find_vio_slot_node(drc_name);
94 if (dn) {
95 *node_type = NODE_TYPE_VIO;
96 return dn;
97 }
98
99 return NULL;
100 }
101
102 /**
103 * find_php_slot - return hotplug slot structure for device node
104 * @dn: target &device_node
105 *
106 * This routine will return the hotplug slot structure
107 * for a given device node. Note that built-in PCI slots
108 * may be dlpar-able, but not hot-pluggable, so this routine
109 * will return NULL for built-in PCI slots.
110 */
find_php_slot(struct device_node * dn)111 static struct slot *find_php_slot(struct device_node *dn)
112 {
113 struct slot *slot, *next;
114
115 list_for_each_entry_safe(slot, next, &rpaphp_slot_head,
116 rpaphp_slot_list) {
117 if (slot->dn == dn)
118 return slot;
119 }
120
121 return NULL;
122 }
123
dlpar_find_new_dev(struct pci_bus * parent,struct device_node * dev_dn)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
dlpar_pci_add_bus(struct device_node * dn)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 pseries_eeh_init_edev_recursive(pdn);
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 %pOF\n",
150 __func__, dn);
151 return;
152 }
153
154 /* Scan below the new bridge */
155 if (pci_is_bridge(dev))
156 of_scan_pci_bridge(dev);
157
158 /* Map IO space for child bus, which may or may not succeed */
159 pcibios_map_io_space(dev->subordinate);
160
161 /* Finish adding it : resource allocation, adding devices, etc...
162 * Note that we need to perform the finish pass on the -parent-
163 * bus of the EADS bridge so the bridge device itself gets
164 * properly added
165 */
166 pcibios_finish_adding_to_bus(phb->bus);
167 }
168
dlpar_add_pci_slot(char * drc_name,struct device_node * dn)169 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
170 {
171 struct pci_dev *dev;
172 struct pci_controller *phb;
173
174 if (pci_find_bus_by_node(dn))
175 return -EINVAL;
176
177 /* Add pci bus */
178 dlpar_pci_add_bus(dn);
179
180 /* Confirm new bridge dev was created */
181 phb = PCI_DN(dn)->phb;
182 dev = dlpar_find_new_dev(phb->bus, dn);
183
184 if (!dev) {
185 printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
186 drc_name);
187 return -EIO;
188 }
189
190 if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
191 printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
192 __func__, dev->hdr_type, drc_name);
193 return -EIO;
194 }
195
196 /* Add hotplug slot */
197 if (rpaphp_add_slot(dn)) {
198 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
199 __func__, drc_name);
200 return -EIO;
201 }
202 return 0;
203 }
204
dlpar_remove_phb(char * drc_name,struct device_node * dn)205 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
206 {
207 struct slot *slot;
208 struct pci_dn *pdn;
209 int rc = 0;
210
211 if (!pci_find_bus_by_node(dn))
212 return -EINVAL;
213
214 /* If pci slot is hotpluggable, use hotplug to remove it */
215 slot = find_php_slot(dn);
216 if (slot && rpaphp_deregister_slot(slot)) {
217 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
218 __func__, drc_name);
219 return -EIO;
220 }
221
222 pdn = dn->data;
223 BUG_ON(!pdn || !pdn->phb);
224 rc = remove_phb_dynamic(pdn->phb);
225 if (rc < 0)
226 return rc;
227
228 pdn->phb = NULL;
229
230 return 0;
231 }
232
dlpar_add_phb(char * drc_name,struct device_node * dn)233 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
234 {
235 struct pci_controller *phb;
236
237 if (PCI_DN(dn) && PCI_DN(dn)->phb) {
238 /* PHB already exists */
239 return -EINVAL;
240 }
241
242 phb = init_phb_dynamic(dn);
243 if (!phb)
244 return -EIO;
245
246 if (rpaphp_add_slot(dn)) {
247 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
248 __func__, drc_name);
249 return -EIO;
250 }
251 return 0;
252 }
253
dlpar_add_vio_slot(char * drc_name,struct device_node * dn)254 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
255 {
256 struct vio_dev *vio_dev;
257
258 vio_dev = vio_find_node(dn);
259 if (vio_dev) {
260 put_device(&vio_dev->dev);
261 return -EINVAL;
262 }
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 */
dlpar_add_slot(char * drc_name)285 int 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 of_node_put(dn);
313
314 printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
315 exit:
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 */
dlpar_remove_vio_slot(char * drc_name,struct device_node * dn)330 static 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
340 put_device(&vio_dev->dev);
341
342 return 0;
343 }
344
345 /**
346 * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
347 * @drc_name: drc-name of newly added slot
348 * @dn: &device_node
349 *
350 * Remove the kernel and hotplug representations of a PCI I/O Slot.
351 * Return Codes:
352 * 0 Success
353 * -ENODEV Not a valid drc_name
354 * -EIO Internal PCI Error
355 */
dlpar_remove_pci_slot(char * drc_name,struct device_node * dn)356 static int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
357 {
358 struct pci_bus *bus;
359 struct slot *slot;
360 int ret = 0;
361
362 pci_lock_rescan_remove();
363
364 bus = pci_find_bus_by_node(dn);
365 if (!bus) {
366 ret = -EINVAL;
367 goto out;
368 }
369
370 pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
371 bus->self ? pci_name(bus->self) : "<!PHB!>");
372
373 slot = find_php_slot(dn);
374 if (slot) {
375 pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
376 pci_domain_nr(bus), bus->number);
377
378 if (rpaphp_deregister_slot(slot)) {
379 printk(KERN_ERR
380 "%s: unable to remove hotplug slot %s\n",
381 __func__, drc_name);
382 ret = -EIO;
383 goto out;
384 }
385 }
386
387 /* Remove all devices below slot */
388 pci_hp_remove_devices(bus);
389
390 /* Unmap PCI IO space */
391 if (pcibios_unmap_io_space(bus)) {
392 printk(KERN_ERR "%s: failed to unmap bus range\n",
393 __func__);
394 ret = -ERANGE;
395 goto out;
396 }
397
398 /* Remove the EADS bridge device itself */
399 BUG_ON(!bus->self);
400 pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
401 pci_stop_and_remove_bus_device(bus->self);
402
403 out:
404 pci_unlock_rescan_remove();
405 return ret;
406 }
407
408 /**
409 * dlpar_remove_slot - DLPAR remove an I/O Slot
410 * @drc_name: drc-name of newly added slot
411 *
412 * Remove the kernel and hotplug representations of an I/O Slot.
413 * Return Codes:
414 * 0 Success
415 * -ENODEV Not a valid drc_name
416 * -EINVAL Slot already removed
417 * -ERESTARTSYS Signalled before obtaining lock
418 * -EIO Internal Error
419 */
dlpar_remove_slot(char * drc_name)420 int dlpar_remove_slot(char *drc_name)
421 {
422 struct device_node *dn;
423 int node_type;
424 int rc = 0;
425
426 if (mutex_lock_interruptible(&rpadlpar_mutex))
427 return -ERESTARTSYS;
428
429 dn = find_dlpar_node(drc_name, &node_type);
430 if (!dn) {
431 rc = -ENODEV;
432 goto exit;
433 }
434
435 switch (node_type) {
436 case NODE_TYPE_VIO:
437 rc = dlpar_remove_vio_slot(drc_name, dn);
438 break;
439 case NODE_TYPE_PHB:
440 rc = dlpar_remove_phb(drc_name, dn);
441 break;
442 case NODE_TYPE_SLOT:
443 rc = dlpar_remove_pci_slot(drc_name, dn);
444 break;
445 }
446 of_node_put(dn);
447 vm_unmap_aliases();
448
449 printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
450 exit:
451 mutex_unlock(&rpadlpar_mutex);
452 return rc;
453 }
454
is_dlpar_capable(void)455 static inline int is_dlpar_capable(void)
456 {
457 int rc = rtas_token("ibm,configure-connector");
458
459 return (int) (rc != RTAS_UNKNOWN_SERVICE);
460 }
461
rpadlpar_io_init(void)462 static int __init rpadlpar_io_init(void)
463 {
464
465 if (!is_dlpar_capable()) {
466 printk(KERN_WARNING "%s: partition not DLPAR capable\n",
467 __func__);
468 return -EPERM;
469 }
470
471 return dlpar_sysfs_init();
472 }
473
rpadlpar_io_exit(void)474 static void __exit rpadlpar_io_exit(void)
475 {
476 dlpar_sysfs_exit();
477 }
478
479 module_init(rpadlpar_io_init);
480 module_exit(rpadlpar_io_exit);
481 MODULE_LICENSE("GPL");
482 MODULE_DESCRIPTION("RPA Dynamic Logical Partitioning driver for I/O slots");
483