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/prom.h>
23 #include <asm/machdep.h>
24 #include <linux/uaccess.h>
25 #include <asm/rtas.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 	char *data_buf;
142 	int cc_token;
143 	int rc = -1;
144 
145 	cc_token = rtas_token("ibm,configure-connector");
146 	if (cc_token == RTAS_UNKNOWN_SERVICE)
147 		return NULL;
148 
149 	data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
150 	if (!data_buf)
151 		return NULL;
152 
153 	ccwa = (struct cc_workarea *)&data_buf[0];
154 	ccwa->drc_index = drc_index;
155 	ccwa->zero = 0;
156 
157 	do {
158 		/* Since we release the rtas_data_buf lock between configure
159 		 * connector calls we want to re-populate the rtas_data_buffer
160 		 * with the contents of the previous call.
161 		 */
162 		spin_lock(&rtas_data_buf_lock);
163 
164 		memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
165 		rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
166 		memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
167 
168 		spin_unlock(&rtas_data_buf_lock);
169 
170 		if (rtas_busy_delay(rc))
171 			continue;
172 
173 		switch (rc) {
174 		case COMPLETE:
175 			break;
176 
177 		case NEXT_SIBLING:
178 			dn = dlpar_parse_cc_node(ccwa);
179 			if (!dn)
180 				goto cc_error;
181 
182 			dn->parent = last_dn->parent;
183 			last_dn->sibling = dn;
184 			last_dn = dn;
185 			break;
186 
187 		case NEXT_CHILD:
188 			dn = dlpar_parse_cc_node(ccwa);
189 			if (!dn)
190 				goto cc_error;
191 
192 			if (!first_dn) {
193 				dn->parent = parent;
194 				first_dn = dn;
195 			} else {
196 				dn->parent = last_dn;
197 				if (last_dn)
198 					last_dn->child = dn;
199 			}
200 
201 			last_dn = dn;
202 			break;
203 
204 		case NEXT_PROPERTY:
205 			property = dlpar_parse_cc_property(ccwa);
206 			if (!property)
207 				goto cc_error;
208 
209 			if (!last_dn->properties)
210 				last_dn->properties = property;
211 			else
212 				last_property->next = property;
213 
214 			last_property = property;
215 			break;
216 
217 		case PREV_PARENT:
218 			last_dn = last_dn->parent;
219 			break;
220 
221 		case MORE_MEMORY:
222 		case ERR_CFG_USE:
223 		default:
224 			printk(KERN_ERR "Unexpected Error (%d) "
225 			       "returned from configure-connector\n", rc);
226 			goto cc_error;
227 		}
228 	} while (rc);
229 
230 cc_error:
231 	kfree(data_buf);
232 
233 	if (rc) {
234 		if (first_dn)
235 			dlpar_free_cc_nodes(first_dn);
236 
237 		return NULL;
238 	}
239 
240 	return first_dn;
241 }
242 
243 int dlpar_attach_node(struct device_node *dn, struct device_node *parent)
244 {
245 	int rc;
246 
247 	dn->parent = parent;
248 
249 	rc = of_attach_node(dn);
250 	if (rc) {
251 		printk(KERN_ERR "Failed to add device node %pOF\n", dn);
252 		return rc;
253 	}
254 
255 	return 0;
256 }
257 
258 int dlpar_detach_node(struct device_node *dn)
259 {
260 	struct device_node *child;
261 	int rc;
262 
263 	child = of_get_next_child(dn, NULL);
264 	while (child) {
265 		dlpar_detach_node(child);
266 		child = of_get_next_child(dn, child);
267 	}
268 
269 	rc = of_detach_node(dn);
270 	if (rc)
271 		return rc;
272 
273 	of_node_put(dn);
274 
275 	return 0;
276 }
277 
278 #define DR_ENTITY_SENSE		9003
279 #define DR_ENTITY_PRESENT	1
280 #define DR_ENTITY_UNUSABLE	2
281 #define ALLOCATION_STATE	9003
282 #define ALLOC_UNUSABLE		0
283 #define ALLOC_USABLE		1
284 #define ISOLATION_STATE		9001
285 #define ISOLATE			0
286 #define UNISOLATE		1
287 
288 int dlpar_acquire_drc(u32 drc_index)
289 {
290 	int dr_status, rc;
291 
292 	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
293 		       DR_ENTITY_SENSE, drc_index);
294 	if (rc || dr_status != DR_ENTITY_UNUSABLE)
295 		return -1;
296 
297 	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
298 	if (rc)
299 		return rc;
300 
301 	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
302 	if (rc) {
303 		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
304 		return rc;
305 	}
306 
307 	return 0;
308 }
309 
310 int dlpar_release_drc(u32 drc_index)
311 {
312 	int dr_status, rc;
313 
314 	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
315 		       DR_ENTITY_SENSE, drc_index);
316 	if (rc || dr_status != DR_ENTITY_PRESENT)
317 		return -1;
318 
319 	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
320 	if (rc)
321 		return rc;
322 
323 	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
324 	if (rc) {
325 		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
326 		return rc;
327 	}
328 
329 	return 0;
330 }
331 
332 int dlpar_unisolate_drc(u32 drc_index)
333 {
334 	int dr_status, rc;
335 
336 	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
337 				DR_ENTITY_SENSE, drc_index);
338 	if (rc || dr_status != DR_ENTITY_PRESENT)
339 		return -1;
340 
341 	rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
342 
343 	return 0;
344 }
345 
346 int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
347 {
348 	int rc;
349 
350 	/* pseries error logs are in BE format, convert to cpu type */
351 	switch (hp_elog->id_type) {
352 	case PSERIES_HP_ELOG_ID_DRC_COUNT:
353 		hp_elog->_drc_u.drc_count =
354 				be32_to_cpu(hp_elog->_drc_u.drc_count);
355 		break;
356 	case PSERIES_HP_ELOG_ID_DRC_INDEX:
357 		hp_elog->_drc_u.drc_index =
358 				be32_to_cpu(hp_elog->_drc_u.drc_index);
359 		break;
360 	case PSERIES_HP_ELOG_ID_DRC_IC:
361 		hp_elog->_drc_u.ic.count =
362 				be32_to_cpu(hp_elog->_drc_u.ic.count);
363 		hp_elog->_drc_u.ic.index =
364 				be32_to_cpu(hp_elog->_drc_u.ic.index);
365 	}
366 
367 	switch (hp_elog->resource) {
368 	case PSERIES_HP_ELOG_RESOURCE_MEM:
369 		rc = dlpar_memory(hp_elog);
370 		break;
371 	case PSERIES_HP_ELOG_RESOURCE_CPU:
372 		rc = dlpar_cpu(hp_elog);
373 		break;
374 	case PSERIES_HP_ELOG_RESOURCE_PMEM:
375 		rc = dlpar_hp_pmem(hp_elog);
376 		break;
377 
378 	default:
379 		pr_warn_ratelimited("Invalid resource (%d) specified\n",
380 				    hp_elog->resource);
381 		rc = -EINVAL;
382 	}
383 
384 	return rc;
385 }
386 
387 static void pseries_hp_work_fn(struct work_struct *work)
388 {
389 	struct pseries_hp_work *hp_work =
390 			container_of(work, struct pseries_hp_work, work);
391 
392 	handle_dlpar_errorlog(hp_work->errlog);
393 
394 	kfree(hp_work->errlog);
395 	kfree((void *)work);
396 }
397 
398 void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog)
399 {
400 	struct pseries_hp_work *work;
401 	struct pseries_hp_errorlog *hp_errlog_copy;
402 
403 	hp_errlog_copy = kmemdup(hp_errlog, sizeof(*hp_errlog), GFP_ATOMIC);
404 	if (!hp_errlog_copy)
405 		return;
406 
407 	work = kmalloc(sizeof(struct pseries_hp_work), GFP_ATOMIC);
408 	if (work) {
409 		INIT_WORK((struct work_struct *)work, pseries_hp_work_fn);
410 		work->errlog = hp_errlog_copy;
411 		queue_work(pseries_hp_wq, (struct work_struct *)work);
412 	} else {
413 		kfree(hp_errlog_copy);
414 	}
415 }
416 
417 static int dlpar_parse_resource(char **cmd, struct pseries_hp_errorlog *hp_elog)
418 {
419 	char *arg;
420 
421 	arg = strsep(cmd, " ");
422 	if (!arg)
423 		return -EINVAL;
424 
425 	if (sysfs_streq(arg, "memory")) {
426 		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
427 	} else if (sysfs_streq(arg, "cpu")) {
428 		hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_CPU;
429 	} else {
430 		pr_err("Invalid resource specified.\n");
431 		return -EINVAL;
432 	}
433 
434 	return 0;
435 }
436 
437 static int dlpar_parse_action(char **cmd, struct pseries_hp_errorlog *hp_elog)
438 {
439 	char *arg;
440 
441 	arg = strsep(cmd, " ");
442 	if (!arg)
443 		return -EINVAL;
444 
445 	if (sysfs_streq(arg, "add")) {
446 		hp_elog->action = PSERIES_HP_ELOG_ACTION_ADD;
447 	} else if (sysfs_streq(arg, "remove")) {
448 		hp_elog->action = PSERIES_HP_ELOG_ACTION_REMOVE;
449 	} else {
450 		pr_err("Invalid action specified.\n");
451 		return -EINVAL;
452 	}
453 
454 	return 0;
455 }
456 
457 static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog)
458 {
459 	char *arg;
460 	u32 count, index;
461 
462 	arg = strsep(cmd, " ");
463 	if (!arg)
464 		return -EINVAL;
465 
466 	if (sysfs_streq(arg, "indexed-count")) {
467 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_IC;
468 		arg = strsep(cmd, " ");
469 		if (!arg) {
470 			pr_err("No DRC count specified.\n");
471 			return -EINVAL;
472 		}
473 
474 		if (kstrtou32(arg, 0, &count)) {
475 			pr_err("Invalid DRC count specified.\n");
476 			return -EINVAL;
477 		}
478 
479 		arg = strsep(cmd, " ");
480 		if (!arg) {
481 			pr_err("No DRC Index specified.\n");
482 			return -EINVAL;
483 		}
484 
485 		if (kstrtou32(arg, 0, &index)) {
486 			pr_err("Invalid DRC Index specified.\n");
487 			return -EINVAL;
488 		}
489 
490 		hp_elog->_drc_u.ic.count = cpu_to_be32(count);
491 		hp_elog->_drc_u.ic.index = cpu_to_be32(index);
492 	} else if (sysfs_streq(arg, "index")) {
493 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
494 		arg = strsep(cmd, " ");
495 		if (!arg) {
496 			pr_err("No DRC Index specified.\n");
497 			return -EINVAL;
498 		}
499 
500 		if (kstrtou32(arg, 0, &index)) {
501 			pr_err("Invalid DRC Index specified.\n");
502 			return -EINVAL;
503 		}
504 
505 		hp_elog->_drc_u.drc_index = cpu_to_be32(index);
506 	} else if (sysfs_streq(arg, "count")) {
507 		hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_COUNT;
508 		arg = strsep(cmd, " ");
509 		if (!arg) {
510 			pr_err("No DRC count specified.\n");
511 			return -EINVAL;
512 		}
513 
514 		if (kstrtou32(arg, 0, &count)) {
515 			pr_err("Invalid DRC count specified.\n");
516 			return -EINVAL;
517 		}
518 
519 		hp_elog->_drc_u.drc_count = cpu_to_be32(count);
520 	} else {
521 		pr_err("Invalid id_type specified.\n");
522 		return -EINVAL;
523 	}
524 
525 	return 0;
526 }
527 
528 static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
529 			   const char *buf, size_t count)
530 {
531 	struct pseries_hp_errorlog hp_elog;
532 	char *argbuf;
533 	char *args;
534 	int rc;
535 
536 	args = argbuf = kstrdup(buf, GFP_KERNEL);
537 	if (!argbuf)
538 		return -ENOMEM;
539 
540 	/*
541 	 * Parse out the request from the user, this will be in the form:
542 	 * <resource> <action> <id_type> <id>
543 	 */
544 	rc = dlpar_parse_resource(&args, &hp_elog);
545 	if (rc)
546 		goto dlpar_store_out;
547 
548 	rc = dlpar_parse_action(&args, &hp_elog);
549 	if (rc)
550 		goto dlpar_store_out;
551 
552 	rc = dlpar_parse_id_type(&args, &hp_elog);
553 	if (rc)
554 		goto dlpar_store_out;
555 
556 	rc = handle_dlpar_errorlog(&hp_elog);
557 
558 dlpar_store_out:
559 	kfree(argbuf);
560 
561 	if (rc)
562 		pr_err("Could not handle DLPAR request \"%s\"\n", buf);
563 
564 	return rc ? rc : count;
565 }
566 
567 static ssize_t dlpar_show(struct class *class, struct class_attribute *attr,
568 			  char *buf)
569 {
570 	return sprintf(buf, "%s\n", "memory,cpu");
571 }
572 
573 static CLASS_ATTR_RW(dlpar);
574 
575 int __init dlpar_workqueue_init(void)
576 {
577 	if (pseries_hp_wq)
578 		return 0;
579 
580 	pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
581 			WQ_UNBOUND, 1);
582 
583 	return pseries_hp_wq ? 0 : -ENOMEM;
584 }
585 
586 static int __init dlpar_sysfs_init(void)
587 {
588 	int rc;
589 
590 	rc = dlpar_workqueue_init();
591 	if (rc)
592 		return rc;
593 
594 	return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
595 }
596 machine_device_initcall(pseries, dlpar_sysfs_init);
597 
598