aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/pseries/mobility.c
blob: b571285f6c149e272928011d145e6c633776d4a5 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Support for Partition Mobility/Migration
 *
 * Copyright (C) 2010 Nathan Fontenot
 * Copyright (C) 2010 IBM Corporation
 */

#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/stat.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/stringify.h>

#include <asm/machdep.h>
#include <asm/rtas.h>
#include "pseries.h"
#include "../../kernel/cacheinfo.h"

static struct kobject *mobility_kobj;

struct update_props_workarea {
	__be32 phandle;
	__be32 state;
	__be64 reserved;
	__be32 nprops;
} __packed;

#define NODE_ACTION_MASK	0xff000000
#define NODE_COUNT_MASK		0x00ffffff

#define DELETE_DT_NODE	0x01000000
#define UPDATE_DT_NODE	0x02000000
#define ADD_DT_NODE	0x03000000

#define MIGRATION_SCOPE	(1)
#define PRRN_SCOPE -2

static int mobility_rtas_call(int token, char *buf, s32 scope)
{
	int rc;

	spin_lock(&rtas_data_buf_lock);

	memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
	rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
	memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);

	spin_unlock(&rtas_data_buf_lock);
	return rc;
}

static int delete_dt_node(__be32 phandle)
{
	struct device_node *dn;

	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (!dn)
		return -ENOENT;

	dlpar_detach_node(dn);
	of_node_put(dn);
	return 0;
}

static int update_dt_property(struct device_node *dn, struct property **prop,
			      const char *name, u32 vd, char *value)
{
	struct property *new_prop = *prop;
	int more = 0;

	/* A negative 'vd' value indicates that only part of the new property
	 * value is contained in the buffer and we need to call
	 * ibm,update-properties again to get the rest of the value.
	 *
	 * A negative value is also the two's compliment of the actual value.
	 */
	if (vd & 0x80000000) {
		vd = ~vd + 1;
		more = 1;
	}

	if (new_prop) {
		/* partial property fixup */
		char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
		if (!new_data)
			return -ENOMEM;

		memcpy(new_data, new_prop->value, new_prop->length);
		memcpy(new_data + new_prop->length, value, vd);

		kfree(new_prop->value);
		new_prop->value = new_data;
		new_prop->length += vd;
	} else {
		new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
		if (!new_prop)
			return -ENOMEM;

		new_prop->name = kstrdup(name, GFP_KERNEL);
		if (!new_prop->name) {
			kfree(new_prop);
			return -ENOMEM;
		}

		new_prop->length = vd;
		new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
		if (!new_prop->value) {
			kfree(new_prop->name);
			kfree(new_prop);
			return -ENOMEM;
		}

		memcpy(new_prop->value, value, vd);
		*prop = new_prop;
	}

	if (!more) {
		of_update_property(dn, new_prop);
		*prop = NULL;
	}

	return 0;
}

static int update_dt_node(__be32 phandle, s32 scope)
{
	struct update_props_workarea *upwa;
	struct device_node *dn;
	struct property *prop = NULL;
	int i, rc, rtas_rc;
	char *prop_data;
	char *rtas_buf;
	int update_properties_token;
	u32 nprops;
	u32 vd;

	update_properties_token = rtas_token("ibm,update-properties");
	if (update_properties_token == RTAS_UNKNOWN_SERVICE)
		return -EINVAL;

	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
	if (!rtas_buf)
		return -ENOMEM;

	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (!dn) {
		kfree(rtas_buf);
		return -ENOENT;
	}

	upwa = (struct update_props_workarea *)&rtas_buf[0];
	upwa->phandle = phandle;

	do {
		rtas_rc = mobility_rtas_call(update_properties_token, rtas_buf,
					scope);
		if (rtas_rc < 0)
			break;

		prop_data = rtas_buf + sizeof(*upwa);
		nprops = be32_to_cpu(upwa->nprops);

		/* On the first call to ibm,update-properties for a node the
		 * the first property value descriptor contains an empty
		 * property name, the property value length encoded as u32,
		 * and the property value is the node path being updated.
		 */
		if (*prop_data == 0) {
			prop_data++;
			vd = be32_to_cpu(*(__be32 *)prop_data);
			prop_data += vd + sizeof(vd);
			nprops--;
		}

		for (i = 0; i < nprops; i++) {
			char *prop_name;

			prop_name = prop_data;
			prop_data += strlen(prop_name) + 1;
			vd = be32_to_cpu(*(__be32 *)prop_data);
			prop_data += sizeof(vd);

			switch (vd) {
			case 0x00000000:
				/* name only property, nothing to do */
				break;

			case 0x80000000:
				of_remove_property(dn, of_find_property(dn,
							prop_name, NULL));
				prop = NULL;
				break;

			default:
				rc = update_dt_property(dn, &prop, prop_name,
							vd, prop_data);
				if (rc) {
					printk(KERN_ERR "Could not update %s"
					       " property\n", prop_name);
				}

				prop_data += vd;
			}

			cond_resched();
		}

		cond_resched();
	} while (rtas_rc == 1);

	of_node_put(dn);
	kfree(rtas_buf);
	return 0;
}

static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
{
	struct device_node *dn;
	struct device_node *parent_dn;
	int rc;

	parent_dn = of_find_node_by_phandle(be32_to_cpu(parent_phandle));
	if (!parent_dn)
		return -ENOENT;

	dn = dlpar_configure_connector(drc_index, parent_dn);
	if (!dn) {
		of_node_put(parent_dn);
		return -ENOENT;
	}

	rc = dlpar_attach_node(dn, parent_dn);
	if (rc)
		dlpar_free_cc_nodes(dn);

	of_node_put(parent_dn);
	return rc;
}

static void prrn_update_node(__be32 phandle)
{
	struct pseries_hp_errorlog hp_elog;
	struct device_node *dn;

	/*
	 * If a node is found from a the given phandle, the phandle does not
	 * represent the drc index of an LMB and we can ignore.
	 */
	dn = of_find_node_by_phandle(be32_to_cpu(phandle));
	if (dn) {
		of_node_put(dn);
		return;
	}

	hp_elog.resource = PSERIES_HP_ELOG_RESOURCE_MEM;
	hp_elog.action = PSERIES_HP_ELOG_ACTION_READD;
	hp_elog.id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
	hp_elog._drc_u.drc_index = phandle;

	handle_dlpar_errorlog(&hp_elog);
}

int pseries_devicetree_update(s32 scope)
{
	char *rtas_buf;
	__be32 *data;
	int update_nodes_token;
	int rc;

	update_nodes_token = rtas_token("ibm,update-nodes");
	if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
		return -EINVAL;

	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
	if (!rtas_buf)
		return -ENOMEM;

	do {
		rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
		if (rc && rc != 1)
			break;

		data = (__be32 *)rtas_buf + 4;
		while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
			int i;
			u32 action = be32_to_cpu(*data) & NODE_ACTION_MASK;
			u32 node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;

			data++;

			for (i = 0; i < node_count; i++) {
				__be32 phandle = *data++;
				__be32 drc_index;

				switch (action) {
				case DELETE_DT_NODE:
					delete_dt_node(phandle);
					break;
				case UPDATE_DT_NODE:
					update_dt_node(phandle, scope);

					if (scope == PRRN_SCOPE)
						prrn_update_node(phandle);

					break;
				case ADD_DT_NODE:
					drc_index = *data++;
					add_dt_node(phandle, drc_index);
					break;
				}

				cond_resched();
			}
		}

		cond_resched();
	} while (rc == 1);

	kfree(rtas_buf);
	return rc;
}

void post_mobility_fixup(void)
{
	int rc;
	int activate_fw_token;

	activate_fw_token = rtas_token("ibm,activate-firmware");
	if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
		printk(KERN_ERR "Could not make post-mobility "
		       "activate-fw call.\n");
		return;
	}

	do {
		rc = rtas_call(activate_fw_token, 0, 1, NULL);
	} while (rtas_busy_delay(rc));

	if (rc)
		printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);

	/*
	 * We don't want CPUs to go online/offline while the device
	 * tree is being updated.
	 */
	cpus_read_lock();

	/*
	 * It's common for the destination firmware to replace cache
	 * nodes.  Release all of the cacheinfo hierarchy's references
	 * before updating the device tree.
	 */
	cacheinfo_teardown();

	rc = pseries_devicetree_update(MIGRATION_SCOPE);
	if (rc)
		printk(KERN_ERR "Post-mobility device tree update "
			"failed: %d\n", rc);

	cacheinfo_rebuild();

	cpus_read_unlock();

	/* Possibly switch to a new RFI flush type */
	pseries_setup_rfi_flush();

	return;
}

static ssize_t migration_store(struct class *class,
			       struct class_attribute *attr, const char *buf,
			       size_t count)
{
	u64 streamid;
	int rc;

	rc = kstrtou64(buf, 0, &streamid);
	if (rc)
		return rc;

	stop_topology_update();

	do {
		rc = rtas_ibm_suspend_me(streamid);
		if (rc == -EAGAIN)
			ssleep(1);
	} while (rc == -EAGAIN);

	if (rc)
		return rc;

	post_mobility_fixup();

	start_topology_update();

	return count;
}

/*
 * Used by drmgr to determine the kernel behavior of the migration interface.
 *
 * Version 1: Performs all PAPR requirements for migration including
 *	firmware activation and device tree update.
 */
#define MIGRATION_API_VERSION	1

static CLASS_ATTR_WO(migration);
static CLASS_ATTR_STRING(api_version, 0444, __stringify(MIGRATION_API_VERSION));

static int __init mobility_sysfs_init(void)
{
	int rc;

	mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
	if (!mobility_kobj)
		return -ENOMEM;

	rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
	if (rc)
		pr_err("mobility: unable to create migration sysfs file (%d)\n", rc);

	rc = sysfs_create_file(mobility_kobj, &class_attr_api_version.attr.attr);
	if (rc)
		pr_err("mobility: unable to create api_version sysfs file (%d)\n", rc);

	return 0;
}
machine_device_initcall(pseries, mobility_sysfs_init);