1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Support for dynamic reconfiguration for PCI, Memory, and CPU
4  * Hotplug and Dynamic Logical Partitioning on RPA platforms.
5  *
6  * Copyright (C) 2009 Nathan Fontenot
7  * Copyright (C) 2009 IBM Corporation
8  */
9 
10 #define pr_fmt(fmt)	"dlpar: " fmt
11 
12 #include <linux/kernel.h>
13 #include <linux/notifier.h>
14 #include <linux/spinlock.h>
15 #include <linux/cpu.h>
16 #include <linux/slab.h>
17 #include <linux/of.h>
18 
19 #include "of_helpers.h"
20 #include "pseries.h"
21 
22 #include <asm/machdep.h>
23 #include <linux/uaccess.h>
24 #include <asm/rtas.h>
25 #include <asm/rtas-work-area.h>
26 
27 static struct workqueue_struct *pseries_hp_wq;
28 
29 struct pseries_hp_work {
30 	struct work_struct work;
31 	struct pseries_hp_errorlog *errlog;
32 };
33 
34 struct cc_workarea {
35 	__be32	drc_index;
36 	__be32	zero;
37 	__be32	name_offset;
38 	__be32	prop_length;
39 	__be32	prop_offset;
40 };
41 
42 void dlpar_free_cc_property(struct property *prop)
43 {
44 	kfree(prop->name);
45 	kfree(prop->value);
46 	kfree(prop);
47 }
48 
49 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
50 {
51 	struct property *prop;
52 	char *name;
53 	char *value;
54 
55 	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
56 	if (!prop)
57 		return NULL;
58 
59 	name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
60 	prop->name = kstrdup(name, GFP_KERNEL);
61 	if (!prop->name) {
62 		dlpar_free_cc_property(prop);
63 		return NULL;
64 	}
65 
66 	prop->length = be32_to_cpu(ccwa->prop_length);
67 	value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
68 	prop->value = kmemdup(value, prop->length, GFP_KERNEL);
69 	if (!prop->value) {
70 		dlpar_free_cc_property(prop);
71 		return NULL;
72 	}
73 
74 	return prop;
75 }
76 
77 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa)
78 {
79 	struct device_node *dn;
80 	const char *name;
81 
82 	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
83 	if (!dn)
84 		return NULL;
85 
86 	name = (const char *)ccwa + be32_to_cpu(ccwa->name_offset);
87 	dn->full_name = kstrdup(name, GFP_KERNEL);
88 	if (!dn->full_name) {
89 		kfree(dn);
90 		return NULL;
91 	}
92 
93 	of_node_set_flag(dn, OF_DYNAMIC);
94 	of_node_init(dn);
95 
96 	return dn;
97 }
98 
99 static void dlpar_free_one_cc_node(struct device_node *dn)
100 {
101 	struct property *prop;
102 
103 	while (dn->properties) {
104 		prop = dn->properties;
105 		dn->properties = prop->next;
106 		dlpar_free_cc_property(prop);
107 	}
108 
109 	kfree(dn->full_name);
110 	kfree(dn);
111 }
112 
113 void dlpar_free_cc_nodes(struct device_node *dn)
114 {
115 	if (dn->child)
116 		dlpar_free_cc_nodes(dn->child);
117 
118 	if (dn->sibling)
119 		dlpar_free_cc_nodes(dn->sibling);
120 
121 	dlpar_free_one_cc_node(dn);
122 }
123 
124 #define COMPLETE	0
125 #define NEXT_SIBLING    1
126 #define NEXT_CHILD      2
127 #define NEXT_PROPERTY   3
128 #define PREV_PARENT     4
129 #define MORE_MEMORY     5
130 #define ERR_CFG_USE     -9003
131 
132 struct device_node *dlpar_configure_connector(__be32 drc_index,
133 					      struct device_node *parent)
134 {
135 	struct device_node *dn;
136 	struct device_node *first_dn = NULL;
137 	struct device_node *last_dn = NULL;
138 	struct property *property;
139 	struct property *last_property = NULL;
140 	struct cc_workarea *ccwa;
141 	struct rtas_work_area *work_area;
142 	char *data_buf;
143 	int cc_token;
144 	int rc = -1;
145 
146 	cc_token = rtas_function_token(RTAS_FN_IBM_CONFIGURE_CONNECTOR);
147 	if (cc_token == RTAS_UNKNOWN_SERVICE)
148 		return NULL;
149 
150 	work_area = rtas_work_area_alloc(SZ_4K);
151 	data_buf = rtas_work_area_raw_buf(work_area);
152 
153 	ccwa = (struct cc_workarea *)&data_buf[0];
154 	ccwa->drc_index = drc_index;
155 	ccwa->zero = 0;
156 
157 	do {
158 		do {
159 			rc = rtas_call(cc_token, 2, 1, NULL,
160 				       rtas_work_area_phys(work_area), NULL);
161 		} while (rtas_busy_delay(rc));
162 
163 		switch (rc) {
164 		case COMPLETE:
165 			break;
166 
167 		case NEXT_SIBLING:
168 			dn = dlpar_parse_cc_node(ccwa);
169 			if (!dn)
170 				goto cc_error;
171 
172 			dn->parent = last_dn->parent;
173 			last_dn->sibling = dn;
174 			last_dn = dn;
175 			break;
176 
177 		case NEXT_CHILD:
178 			dn = dlpar_parse_cc_node(ccwa);
179 			if (!dn)
180 				goto cc_error;
181 
182 			if (!first_dn) {
183 				dn->parent = parent;
184 				first_dn = dn;
185 			} else {
186 				dn->parent = last_dn;
187 				if (last_dn)
188 					last_dn->child = dn;
189 			}
190 
191 			last_dn = dn;
192 			break;
193 
194 		case NEXT_PROPERTY:
195 			property = dlpar_parse_cc_property(ccwa);
196 			if (!property)
197 				goto cc_error;
198 
199 			if (!last_dn->properties)
200 				last_dn->properties = property;
201 			else
202 				last_property->next = property;
203 
204 			last_property = property;
205 			break;
206 
207 		case PREV_PARENT:
208 			last_dn = last_dn->parent;
209 			break;
210 
211 		case MORE_MEMORY:
212 		case ERR_CFG_USE:
213 		default:
214 			printk(KERN_ERR "Unexpected Error (%d) "
215 			       "returned from configure-connector\n", rc);
216 			goto cc_error;
217 		}
218 	} while (rc);
219 
220 cc_error:
221 	rtas_work_area_free(work_area);
222 
223 	if (rc) {
224 		if (first_dn)
225 			dlpar_free_cc_nodes(first_dn);
226 
227 		return NULL;
228 	}
229 
230 	return first_dn;
231 }
232 
233 int dlpar_attach_node(struct device_node *dn, struct device_node *parent)
234 {
235 	int rc;
236 
237 	dn->parent = parent;
238 
239 	rc = of_attach_node(dn);
240 	if (rc) {
241 		printk(KERN_ERR "Failed to add device node %pOF\n", dn);
242 		return rc;
243 	}
244 
245 	return 0;
246 }
247 
248 int dlpar_detach_node(struct device_node *dn)
249 {
250 	struct device_node *child;
251 	int rc;
252 
253 	child = of_get_next_child(dn, NULL);
254 	while (child) {
255 		dlpar_detach_node(child);
256 		child = of_get_next_child(dn, child);
257 	}
258 
259 	rc = of_detach_node(dn);
260 	if (rc)
261 		return rc;
262 
263 	of_node_put(dn);
264 
265 	return 0;
266 }
267 
268 #define DR_ENTITY_SENSE		9003
269 #define DR_ENTITY_PRESENT	1
270 #define DR_ENTITY_UNUSABLE	2
271 #define ALLOCATION_STATE	9003
272 #define ALLOC_UNUSABLE		0
273 #define ALLOC_USABLE		1
274 #define ISOLATION_STATE		9001
275 #define ISOLATE			0
276 #define UNISOLATE		1
277 
278 int dlpar_acquire_drc(u32 drc_index)
279 {
280 	int dr_status, rc;
281 
282 	rc = rtas_get_sensor(DR_ENTITY_SENSE, drc_index, &dr_status);
283 	if (rc || dr_status != DR_ENTITY_UNUSABLE)
284 		return -1;
285 
286 	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
287 	if (rc)
288 		return rc;
289 
290 	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
291 	if (rc) {
292 		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
293 		return rc;
294 	}
295 
296 	return 0;
297 }
298 
299 int dlpar_release_drc(u32 drc_index)
300 {
301 	int dr_status, rc;
302 
303 	rc = rtas_get_sensor(DR_ENTITY_SENSE, drc_index, &dr_status);
304 	if (rc || dr_status != DR_ENTITY_PRESENT)
305 		return -1;
306 
307 	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
308 	if (rc)
309 		return rc;
310 
311 	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
312 	if (rc) {
313 		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
314 		return rc;
315 	}
316 
317 	return 0;
318 }
319 
320 int dlpar_unisolate_drc(u32 drc_index)
321 {
322 	int dr_status, rc;
323 
324 	rc = rtas_get_sensor(DR_ENTITY_SENSE, drc_index, &dr_status);
325 	if (rc || dr_status != DR_ENTITY_PRESENT)
326 		return -1;
327 
328 	rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
329 
330 	return 0;
331 }
332 
333 int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
334 {
335 	int rc;
336 
337 	/* pseries error logs are in BE format, convert to cpu type */
338 	switch (hp_elog->id_type) {
339 	case PSERIES_HP_ELOG_ID_DRC_COUNT:
340 		hp_elog->_drc_u.drc_count =
341 				be32_to_cpu(hp_elog->_drc_u.drc_count);
342 		break;
343 	case PSERIES_HP_ELOG_ID_DRC_INDEX:
344 		hp_elog->_drc_u.drc_index =
345 				be32_to_cpu(hp_elog->_drc_u.drc_index);
346 		break;
347 	case PSERIES_HP_ELOG_ID_DRC_IC:
348 		hp_elog->_drc_u.ic.count =
349 				be32_to_cpu(hp_elog->_drc_u.ic.count);
350 		hp_elog->_drc_u.ic.index =
351 				be32_to_cpu(hp_elog->_drc_u.ic.index);
352 	}
353 
354 	switch (hp_elog->resource) {
355 	case PSERIES_HP_ELOG_RESOURCE_MEM:
356 		rc = dlpar_memory(hp_elog);
357 		break;
358 	case PSERIES_HP_ELOG_RESOURCE_CPU:
359 		rc = dlpar_cpu(hp_elog);
360 		break;
361 	case PSERIES_HP_ELOG_RESOURCE_PMEM:
362 		rc = dlpar_hp_pmem(hp_elog);
363 		break;
364 
365 	default:
366 		pr_warn_ratelimited("Invalid resource (%d) specified\n",
367 				    hp_elog->resource);
368 		rc = -EINVAL;
369 	}
370 
371 	return rc;
372 }
373 
374 static void pseries_hp_work_fn(struct work_struct *work)
375 {
376 	struct pseries_hp_work *hp_work =
377 			container_of(work, struct pseries_hp_work, work);
378 
379 	handle_dlpar_errorlog(hp_work->errlog);
380 
381 	kfree(hp_work->errlog);
382 	kfree(work);
383 }
384 
385 void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog)
386 {
387 	struct pseries_hp_work *work;
388 	struct pseries_hp_errorlog *hp_errlog_copy;
389 
390 	hp_errlog_copy = kmemdup(hp_errlog, sizeof(*hp_errlog), GFP_ATOMIC);
391 	if (!hp_errlog_copy)
392 		return;
393 
394 	work = kmalloc(sizeof(struct pseries_hp_work), GFP_ATOMIC);
395 	if (work) {
396 		INIT_WORK((struct work_struct *)work, pseries_hp_work_fn);
397 		work->errlog = hp_errlog_copy;
398 		queue_work(pseries_hp_wq, (struct work_struct *)work);
399 	} else {
400 		kfree(hp_errlog_copy);
401 	}
402 }
403 
404 static int dlpar_parse_resource(char **cmd, struct pseries_hp_errorlog *hp_elog)
405 {
406 	char *arg;
407 
408 	arg = strsep(cmd, " ");
409 	if (!arg)
410 		return -EINVAL;
411 
412 	if (sysfs_streq(arg, "memory")) {
413 		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
414 	} else if (sysfs_streq(arg, "cpu")) {
415 		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_CPU;
416 	} else {
417 		pr_err("Invalid resource specified.\n");
418 		return -EINVAL;
419 	}
420 
421 	return 0;
422 }
423 
424 static int dlpar_parse_action(char **cmd, struct pseries_hp_errorlog *hp_elog)
425 {
426 	char *arg;
427 
428 	arg = strsep(cmd, " ");
429 	if (!arg)
430 		return -EINVAL;
431 
432 	if (sysfs_streq(arg, "add")) {
433 		hp_elog->action = PSERIES_HP_ELOG_ACTION_ADD;
434 	} else if (sysfs_streq(arg, "remove")) {
435 		hp_elog->action = PSERIES_HP_ELOG_ACTION_REMOVE;
436 	} else {
437 		pr_err("Invalid action specified.\n");
438 		return -EINVAL;
439 	}
440 
441 	return 0;
442 }
443 
444 static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog)
445 {
446 	char *arg;
447 	u32 count, index;
448 
449 	arg = strsep(cmd, " ");
450 	if (!arg)
451 		return -EINVAL;
452 
453 	if (sysfs_streq(arg, "indexed-count")) {
454 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_IC;
455 		arg = strsep(cmd, " ");
456 		if (!arg) {
457 			pr_err("No DRC count specified.\n");
458 			return -EINVAL;
459 		}
460 
461 		if (kstrtou32(arg, 0, &count)) {
462 			pr_err("Invalid DRC count specified.\n");
463 			return -EINVAL;
464 		}
465 
466 		arg = strsep(cmd, " ");
467 		if (!arg) {
468 			pr_err("No DRC Index specified.\n");
469 			return -EINVAL;
470 		}
471 
472 		if (kstrtou32(arg, 0, &index)) {
473 			pr_err("Invalid DRC Index specified.\n");
474 			return -EINVAL;
475 		}
476 
477 		hp_elog->_drc_u.ic.count = cpu_to_be32(count);
478 		hp_elog->_drc_u.ic.index = cpu_to_be32(index);
479 	} else if (sysfs_streq(arg, "index")) {
480 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
481 		arg = strsep(cmd, " ");
482 		if (!arg) {
483 			pr_err("No DRC Index specified.\n");
484 			return -EINVAL;
485 		}
486 
487 		if (kstrtou32(arg, 0, &index)) {
488 			pr_err("Invalid DRC Index specified.\n");
489 			return -EINVAL;
490 		}
491 
492 		hp_elog->_drc_u.drc_index = cpu_to_be32(index);
493 	} else if (sysfs_streq(arg, "count")) {
494 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_COUNT;
495 		arg = strsep(cmd, " ");
496 		if (!arg) {
497 			pr_err("No DRC count specified.\n");
498 			return -EINVAL;
499 		}
500 
501 		if (kstrtou32(arg, 0, &count)) {
502 			pr_err("Invalid DRC count specified.\n");
503 			return -EINVAL;
504 		}
505 
506 		hp_elog->_drc_u.drc_count = cpu_to_be32(count);
507 	} else {
508 		pr_err("Invalid id_type specified.\n");
509 		return -EINVAL;
510 	}
511 
512 	return 0;
513 }
514 
515 static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
516 			   const char *buf, size_t count)
517 {
518 	struct pseries_hp_errorlog hp_elog;
519 	char *argbuf;
520 	char *args;
521 	int rc;
522 
523 	args = argbuf = kstrdup(buf, GFP_KERNEL);
524 	if (!argbuf)
525 		return -ENOMEM;
526 
527 	/*
528 	 * Parse out the request from the user, this will be in the form:
529 	 * <resource> <action> <id_type> <id>
530 	 */
531 	rc = dlpar_parse_resource(&args, &hp_elog);
532 	if (rc)
533 		goto dlpar_store_out;
534 
535 	rc = dlpar_parse_action(&args, &hp_elog);
536 	if (rc)
537 		goto dlpar_store_out;
538 
539 	rc = dlpar_parse_id_type(&args, &hp_elog);
540 	if (rc)
541 		goto dlpar_store_out;
542 
543 	rc = handle_dlpar_errorlog(&hp_elog);
544 
545 dlpar_store_out:
546 	kfree(argbuf);
547 
548 	if (rc)
549 		pr_err("Could not handle DLPAR request \"%s\"\n", buf);
550 
551 	return rc ? rc : count;
552 }
553 
554 static ssize_t dlpar_show(struct class *class, struct class_attribute *attr,
555 			  char *buf)
556 {
557 	return sprintf(buf, "%s\n", "memory,cpu");
558 }
559 
560 static CLASS_ATTR_RW(dlpar);
561 
562 int __init dlpar_workqueue_init(void)
563 {
564 	if (pseries_hp_wq)
565 		return 0;
566 
567 	pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
568 			WQ_UNBOUND, 1);
569 
570 	return pseries_hp_wq ? 0 : -ENOMEM;
571 }
572 
573 static int __init dlpar_sysfs_init(void)
574 {
575 	int rc;
576 
577 	rc = dlpar_workqueue_init();
578 	if (rc)
579 		return rc;
580 
581 	return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
582 }
583 machine_device_initcall(pseries, dlpar_sysfs_init);
584 
585