summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/pseries/dlpar.c
blob: c22bb1b4beb878c50bbe2f3c8d4dba7fd5d142f1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
/*
 * Support for dynamic reconfiguration for PCI, Memory, and CPU
 * Hotplug and Dynamic Logical Partitioning on RPA platforms.
 *
 * Copyright (C) 2009 Nathan Fontenot
 * Copyright (C) 2009 IBM Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/notifier.h>
#include <linux/spinlock.h>
#include <linux/cpu.h>
#include <linux/slab.h>
#include <linux/of.h>
#include "offline_states.h"
#include "pseries.h"

#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/uaccess.h>
#include <asm/rtas.h>

struct cc_workarea {
	__be32	drc_index;
	__be32	zero;
	__be32	name_offset;
	__be32	prop_length;
	__be32	prop_offset;
};

void dlpar_free_cc_property(struct property *prop)
{
	kfree(prop->name);
	kfree(prop->value);
	kfree(prop);
}

static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
{
	struct property *prop;
	char *name;
	char *value;

	prop = kzalloc(sizeof(*prop), GFP_KERNEL);
	if (!prop)
		return NULL;

	name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
	prop->name = kstrdup(name, GFP_KERNEL);

	prop->length = be32_to_cpu(ccwa->prop_length);
	value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
	prop->value = kmemdup(value, prop->length, GFP_KERNEL);
	if (!prop->value) {
		dlpar_free_cc_property(prop);
		return NULL;
	}

	return prop;
}

static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
					       const char *path)
{
	struct device_node *dn;
	char *name;

	/* If parent node path is "/" advance path to NULL terminator to
	 * prevent double leading slashs in full_name.
	 */
	if (!path[1])
		path++;

	dn = kzalloc(sizeof(*dn), GFP_KERNEL);
	if (!dn)
		return NULL;

	name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
	dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name);
	if (!dn->full_name) {
		kfree(dn);
		return NULL;
	}

	of_node_set_flag(dn, OF_DYNAMIC);
	of_node_init(dn);

	return dn;
}

static void dlpar_free_one_cc_node(struct device_node *dn)
{
	struct property *prop;

	while (dn->properties) {
		prop = dn->properties;
		dn->properties = prop->next;
		dlpar_free_cc_property(prop);
	}

	kfree(dn->full_name);
	kfree(dn);
}

void dlpar_free_cc_nodes(struct device_node *dn)
{
	if (dn->child)
		dlpar_free_cc_nodes(dn->child);

	if (dn->sibling)
		dlpar_free_cc_nodes(dn->sibling);

	dlpar_free_one_cc_node(dn);
}

#define COMPLETE	0
#define NEXT_SIBLING    1
#define NEXT_CHILD      2
#define NEXT_PROPERTY   3
#define PREV_PARENT     4
#define MORE_MEMORY     5
#define CALL_AGAIN	-2
#define ERR_CFG_USE     -9003

struct device_node *dlpar_configure_connector(__be32 drc_index,
					      struct device_node *parent)
{
	struct device_node *dn;
	struct device_node *first_dn = NULL;
	struct device_node *last_dn = NULL;
	struct property *property;
	struct property *last_property = NULL;
	struct cc_workarea *ccwa;
	char *data_buf;
	const char *parent_path = parent->full_name;
	int cc_token;
	int rc = -1;

	cc_token = rtas_token("ibm,configure-connector");
	if (cc_token == RTAS_UNKNOWN_SERVICE)
		return NULL;

	data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
	if (!data_buf)
		return NULL;

	ccwa = (struct cc_workarea *)&data_buf[0];
	ccwa->drc_index = drc_index;
	ccwa->zero = 0;

	do {
		/* Since we release the rtas_data_buf lock between configure
		 * connector calls we want to re-populate the rtas_data_buffer
		 * with the contents of the previous call.
		 */
		spin_lock(&rtas_data_buf_lock);

		memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
		rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
		memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);

		spin_unlock(&rtas_data_buf_lock);

		switch (rc) {
		case COMPLETE:
			break;

		case NEXT_SIBLING:
			dn = dlpar_parse_cc_node(ccwa, parent_path);
			if (!dn)
				goto cc_error;

			dn->parent = last_dn->parent;
			last_dn->sibling = dn;
			last_dn = dn;
			break;

		case NEXT_CHILD:
			if (first_dn)
				parent_path = last_dn->full_name;

			dn = dlpar_parse_cc_node(ccwa, parent_path);
			if (!dn)
				goto cc_error;

			if (!first_dn) {
				dn->parent = parent;
				first_dn = dn;
			} else {
				dn->parent = last_dn;
				if (last_dn)
					last_dn->child = dn;
			}

			last_dn = dn;
			break;

		case NEXT_PROPERTY:
			property = dlpar_parse_cc_property(ccwa);
			if (!property)
				goto cc_error;

			if (!last_dn->properties)
				last_dn->properties = property;
			else
				last_property->next = property;

			last_property = property;
			break;

		case PREV_PARENT:
			last_dn = last_dn->parent;
			parent_path = last_dn->parent->full_name;
			break;

		case CALL_AGAIN:
			break;

		case MORE_MEMORY:
		case ERR_CFG_USE:
		default:
			printk(KERN_ERR "Unexpected Error (%d) "
			       "returned from configure-connector\n", rc);
			goto cc_error;
		}
	} while (rc);

cc_error:
	kfree(data_buf);

	if (rc) {
		if (first_dn)
			dlpar_free_cc_nodes(first_dn);

		return NULL;
	}

	return first_dn;
}

static struct device_node *derive_parent(const char *path)
{
	struct device_node *parent;
	char *last_slash;

	last_slash = strrchr(path, '/');
	if (last_slash == path) {
		parent = of_find_node_by_path("/");
	} else {
		char *parent_path;
		int parent_path_len = last_slash - path + 1;
		parent_path = kmalloc(parent_path_len, GFP_KERNEL);
		if (!parent_path)
			return NULL;

		strlcpy(parent_path, path, parent_path_len);
		parent = of_find_node_by_path(parent_path);
		kfree(parent_path);
	}

	return parent;
}

int dlpar_attach_node(struct device_node *dn)
{
	int rc;

	dn->parent = derive_parent(dn->full_name);
	if (!dn->parent)
		return -ENOMEM;

	rc = of_attach_node(dn);
	if (rc) {
		printk(KERN_ERR "Failed to add device node %s\n",
		       dn->full_name);
		return rc;
	}

	of_node_put(dn->parent);
	return 0;
}

int dlpar_detach_node(struct device_node *dn)
{
	struct device_node *child;
	int rc;

	child = of_get_next_child(dn, NULL);
	while (child) {
		dlpar_detach_node(child);
		child = of_get_next_child(dn, child);
	}

	rc = of_detach_node(dn);
	if (rc)
		return rc;

	of_node_put(dn); /* Must decrement the refcount */
	return 0;
}

#define DR_ENTITY_SENSE		9003
#define DR_ENTITY_PRESENT	1
#define DR_ENTITY_UNUSABLE	2
#define ALLOCATION_STATE	9003
#define ALLOC_UNUSABLE		0
#define ALLOC_USABLE		1
#define ISOLATION_STATE		9001
#define ISOLATE			0
#define UNISOLATE		1

int dlpar_acquire_drc(u32 drc_index)
{
	int dr_status, rc;

	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
		       DR_ENTITY_SENSE, drc_index);
	if (rc || dr_status != DR_ENTITY_UNUSABLE)
		return -1;

	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
	if (rc)
		return rc;

	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
	if (rc) {
		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
		return rc;
	}

	return 0;
}

int dlpar_release_drc(u32 drc_index)
{
	int dr_status, rc;

	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
		       DR_ENTITY_SENSE, drc_index);
	if (rc || dr_status != DR_ENTITY_PRESENT)
		return -1;

	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
	if (rc)
		return rc;

	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
	if (rc) {
		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
		return rc;
	}

	return 0;
}

#ifdef CONFIG_ARCH_CPU_PROBE_RELEASE

static int dlpar_online_cpu(struct device_node *dn)
{
	int rc = 0;
	unsigned int cpu;
	int len, nthreads, i;
	const __be32 *intserv;
	u32 thread;

	intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
	if (!intserv)
		return -EINVAL;

	nthreads = len / sizeof(u32);

	cpu_maps_update_begin();
	for (i = 0; i < nthreads; i++) {
		thread = be32_to_cpu(intserv[i]);
		for_each_present_cpu(cpu) {
			if (get_hard_smp_processor_id(cpu) != thread)
				continue;
			BUG_ON(get_cpu_current_state(cpu)
					!= CPU_STATE_OFFLINE);
			cpu_maps_update_done();
			rc = device_online(get_cpu_device(cpu));
			if (rc)
				goto out;
			cpu_maps_update_begin();

			break;
		}
		if (cpu == num_possible_cpus())
			printk(KERN_WARNING "Could not find cpu to online "
			       "with physical id 0x%x\n", thread);
	}
	cpu_maps_update_done();

out:
	return rc;

}

static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
{
	struct device_node *dn, *parent;
	u32 drc_index;
	int rc;

	rc = kstrtou32(buf, 0, &drc_index);
	if (rc)
		return -EINVAL;

	parent = of_find_node_by_path("/cpus");
	if (!parent)
		return -ENODEV;

	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
	if (!dn)
		return -EINVAL;

	of_node_put(parent);

	rc = dlpar_acquire_drc(drc_index);
	if (rc) {
		dlpar_free_cc_nodes(dn);
		return -EINVAL;
	}

	rc = dlpar_attach_node(dn);
	if (rc) {
		dlpar_release_drc(drc_index);
		dlpar_free_cc_nodes(dn);
		return rc;
	}

	rc = dlpar_online_cpu(dn);
	if (rc)
		return rc;

	return count;
}

static int dlpar_offline_cpu(struct device_node *dn)
{
	int rc = 0;
	unsigned int cpu;
	int len, nthreads, i;
	const __be32 *intserv;
	u32 thread;

	intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
	if (!intserv)
		return -EINVAL;

	nthreads = len / sizeof(u32);

	cpu_maps_update_begin();
	for (i = 0; i < nthreads; i++) {
		thread = be32_to_cpu(intserv[i]);
		for_each_present_cpu(cpu) {
			if (get_hard_smp_processor_id(cpu) != thread)
				continue;

			if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
				break;

			if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
				set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
				cpu_maps_update_done();
				rc = device_offline(get_cpu_device(cpu));
				if (rc)
					goto out;
				cpu_maps_update_begin();
				break;

			}

			/*
			 * The cpu is in CPU_STATE_INACTIVE.
			 * Upgrade it's state to CPU_STATE_OFFLINE.
			 */
			set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
			BUG_ON(plpar_hcall_norets(H_PROD, thread)
								!= H_SUCCESS);
			__cpu_die(cpu);
			break;
		}
		if (cpu == num_possible_cpus())
			printk(KERN_WARNING "Could not find cpu to offline "
			       "with physical id 0x%x\n", thread);
	}
	cpu_maps_update_done();

out:
	return rc;

}

static ssize_t dlpar_cpu_release(const char *buf, size_t count)
{
	struct device_node *dn;
	u32 drc_index;
	int rc;

	dn = of_find_node_by_path(buf);
	if (!dn)
		return -EINVAL;

	rc = of_property_read_u32(dn, "ibm,my-drc-index", &drc_index);
	if (rc) {
		of_node_put(dn);
		return -EINVAL;
	}

	rc = dlpar_offline_cpu(dn);
	if (rc) {
		of_node_put(dn);
		return -EINVAL;
	}

	rc = dlpar_release_drc(drc_index);
	if (rc) {
		of_node_put(dn);
		return rc;
	}

	rc = dlpar_detach_node(dn);
	if (rc) {
		dlpar_acquire_drc(drc_index);
		return rc;
	}

	of_node_put(dn);

	return count;
}

static int __init pseries_dlpar_init(void)
{
	ppc_md.cpu_probe = dlpar_cpu_probe;
	ppc_md.cpu_release = dlpar_cpu_release;

	return 0;
}
machine_device_initcall(pseries, pseries_dlpar_init);

#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */