xref: /linux/arch/powerpc/platforms/pseries/mobility.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * Support for Partition Mobility/Migration
3  *
4  * Copyright (C) 2010 Nathan Fontenot
5  * Copyright (C) 2010 IBM Corporation
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License version
9  * 2 as published by the Free Software Foundation.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/kobject.h>
14 #include <linux/smp.h>
15 #include <linux/stat.h>
16 #include <linux/completion.h>
17 #include <linux/device.h>
18 #include <linux/delay.h>
19 #include <linux/slab.h>
20 
21 #include <asm/rtas.h>
22 #include "pseries.h"
23 
24 static struct kobject *mobility_kobj;
25 
26 struct update_props_workarea {
27 	u32 phandle;
28 	u32 state;
29 	u64 reserved;
30 	u32 nprops;
31 };
32 
33 #define NODE_ACTION_MASK	0xff000000
34 #define NODE_COUNT_MASK		0x00ffffff
35 
36 #define DELETE_DT_NODE	0x01000000
37 #define UPDATE_DT_NODE	0x02000000
38 #define ADD_DT_NODE	0x03000000
39 
40 static int mobility_rtas_call(int token, char *buf)
41 {
42 	int rc;
43 
44 	spin_lock(&rtas_data_buf_lock);
45 
46 	memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
47 	rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, 1);
48 	memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
49 
50 	spin_unlock(&rtas_data_buf_lock);
51 	return rc;
52 }
53 
54 static int delete_dt_node(u32 phandle)
55 {
56 	struct device_node *dn;
57 
58 	dn = of_find_node_by_phandle(phandle);
59 	if (!dn)
60 		return -ENOENT;
61 
62 	dlpar_detach_node(dn);
63 	return 0;
64 }
65 
66 static int update_dt_property(struct device_node *dn, struct property **prop,
67 			      const char *name, u32 vd, char *value)
68 {
69 	struct property *new_prop = *prop;
70 	struct property *old_prop;
71 	int more = 0;
72 
73 	/* A negative 'vd' value indicates that only part of the new property
74 	 * value is contained in the buffer and we need to call
75 	 * ibm,update-properties again to get the rest of the value.
76 	 *
77 	 * A negative value is also the two's compliment of the actual value.
78 	 */
79 	if (vd & 0x80000000) {
80 		vd = ~vd + 1;
81 		more = 1;
82 	}
83 
84 	if (new_prop) {
85 		/* partial property fixup */
86 		char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
87 		if (!new_data)
88 			return -ENOMEM;
89 
90 		memcpy(new_data, new_prop->value, new_prop->length);
91 		memcpy(new_data + new_prop->length, value, vd);
92 
93 		kfree(new_prop->value);
94 		new_prop->value = new_data;
95 		new_prop->length += vd;
96 	} else {
97 		new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
98 		if (!new_prop)
99 			return -ENOMEM;
100 
101 		new_prop->name = kstrdup(name, GFP_KERNEL);
102 		if (!new_prop->name) {
103 			kfree(new_prop);
104 			return -ENOMEM;
105 		}
106 
107 		new_prop->length = vd;
108 		new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
109 		if (!new_prop->value) {
110 			kfree(new_prop->name);
111 			kfree(new_prop);
112 			return -ENOMEM;
113 		}
114 
115 		memcpy(new_prop->value, value, vd);
116 		*prop = new_prop;
117 	}
118 
119 	if (!more) {
120 		old_prop = of_find_property(dn, new_prop->name, NULL);
121 		if (old_prop)
122 			prom_update_property(dn, new_prop, old_prop);
123 		else
124 			prom_add_property(dn, new_prop);
125 
126 		new_prop = NULL;
127 	}
128 
129 	return 0;
130 }
131 
132 static int update_dt_node(u32 phandle)
133 {
134 	struct update_props_workarea *upwa;
135 	struct device_node *dn;
136 	struct property *prop = NULL;
137 	int i, rc;
138 	char *prop_data;
139 	char *rtas_buf;
140 	int update_properties_token;
141 
142 	update_properties_token = rtas_token("ibm,update-properties");
143 	if (update_properties_token == RTAS_UNKNOWN_SERVICE)
144 		return -EINVAL;
145 
146 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
147 	if (!rtas_buf)
148 		return -ENOMEM;
149 
150 	dn = of_find_node_by_phandle(phandle);
151 	if (!dn) {
152 		kfree(rtas_buf);
153 		return -ENOENT;
154 	}
155 
156 	upwa = (struct update_props_workarea *)&rtas_buf[0];
157 	upwa->phandle = phandle;
158 
159 	do {
160 		rc = mobility_rtas_call(update_properties_token, rtas_buf);
161 		if (rc < 0)
162 			break;
163 
164 		prop_data = rtas_buf + sizeof(*upwa);
165 
166 		for (i = 0; i < upwa->nprops; i++) {
167 			char *prop_name;
168 			u32 vd;
169 
170 			prop_name = prop_data + 1;
171 			prop_data += strlen(prop_name) + 1;
172 			vd = *prop_data++;
173 
174 			switch (vd) {
175 			case 0x00000000:
176 				/* name only property, nothing to do */
177 				break;
178 
179 			case 0x80000000:
180 				prop = of_find_property(dn, prop_name, NULL);
181 				prom_remove_property(dn, prop);
182 				prop = NULL;
183 				break;
184 
185 			default:
186 				rc = update_dt_property(dn, &prop, prop_name,
187 							vd, prop_data);
188 				if (rc) {
189 					printk(KERN_ERR "Could not update %s"
190 					       " property\n", prop_name);
191 				}
192 
193 				prop_data += vd;
194 			}
195 		}
196 	} while (rc == 1);
197 
198 	of_node_put(dn);
199 	kfree(rtas_buf);
200 	return 0;
201 }
202 
203 static int add_dt_node(u32 parent_phandle, u32 drc_index)
204 {
205 	struct device_node *dn;
206 	struct device_node *parent_dn;
207 	int rc;
208 
209 	dn = dlpar_configure_connector(drc_index);
210 	if (!dn)
211 		return -ENOENT;
212 
213 	parent_dn = of_find_node_by_phandle(parent_phandle);
214 	if (!parent_dn) {
215 		dlpar_free_cc_nodes(dn);
216 		return -ENOENT;
217 	}
218 
219 	dn->parent = parent_dn;
220 	rc = dlpar_attach_node(dn);
221 	if (rc)
222 		dlpar_free_cc_nodes(dn);
223 
224 	of_node_put(parent_dn);
225 	return rc;
226 }
227 
228 static int pseries_devicetree_update(void)
229 {
230 	char *rtas_buf;
231 	u32 *data;
232 	int update_nodes_token;
233 	int rc;
234 
235 	update_nodes_token = rtas_token("ibm,update-nodes");
236 	if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
237 		return -EINVAL;
238 
239 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
240 	if (!rtas_buf)
241 		return -ENOMEM;
242 
243 	do {
244 		rc = mobility_rtas_call(update_nodes_token, rtas_buf);
245 		if (rc && rc != 1)
246 			break;
247 
248 		data = (u32 *)rtas_buf + 4;
249 		while (*data & NODE_ACTION_MASK) {
250 			int i;
251 			u32 action = *data & NODE_ACTION_MASK;
252 			int node_count = *data & NODE_COUNT_MASK;
253 
254 			data++;
255 
256 			for (i = 0; i < node_count; i++) {
257 				u32 phandle = *data++;
258 				u32 drc_index;
259 
260 				switch (action) {
261 				case DELETE_DT_NODE:
262 					delete_dt_node(phandle);
263 					break;
264 				case UPDATE_DT_NODE:
265 					update_dt_node(phandle);
266 					break;
267 				case ADD_DT_NODE:
268 					drc_index = *data++;
269 					add_dt_node(phandle, drc_index);
270 					break;
271 				}
272 			}
273 		}
274 	} while (rc == 1);
275 
276 	kfree(rtas_buf);
277 	return rc;
278 }
279 
280 void post_mobility_fixup(void)
281 {
282 	int rc;
283 	int activate_fw_token;
284 
285 	rc = pseries_devicetree_update();
286 	if (rc) {
287 		printk(KERN_ERR "Initial post-mobility device tree update "
288 		       "failed: %d\n", rc);
289 		return;
290 	}
291 
292 	activate_fw_token = rtas_token("ibm,activate-firmware");
293 	if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
294 		printk(KERN_ERR "Could not make post-mobility "
295 		       "activate-fw call.\n");
296 		return;
297 	}
298 
299 	rc = rtas_call(activate_fw_token, 0, 1, NULL);
300 	if (!rc) {
301 		rc = pseries_devicetree_update();
302 		if (rc)
303 			printk(KERN_ERR "Secondary post-mobility device tree "
304 			       "update failed: %d\n", rc);
305 	} else {
306 		printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);
307 		return;
308 	}
309 
310 	return;
311 }
312 
313 static ssize_t migrate_store(struct class *class, struct class_attribute *attr,
314 			     const char *buf, size_t count)
315 {
316 	struct rtas_args args;
317 	u64 streamid;
318 	int rc;
319 
320 	rc = strict_strtoull(buf, 0, &streamid);
321 	if (rc)
322 		return rc;
323 
324 	memset(&args, 0, sizeof(args));
325 	args.token = rtas_token("ibm,suspend-me");
326 	args.nargs = 2;
327 	args.nret = 1;
328 
329 	args.args[0] = streamid >> 32 ;
330 	args.args[1] = streamid & 0xffffffff;
331 	args.rets = &args.args[args.nargs];
332 
333 	do {
334 		args.rets[0] = 0;
335 		rc = rtas_ibm_suspend_me(&args);
336 		if (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE)
337 			ssleep(1);
338 	} while (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE);
339 
340 	if (rc)
341 		return rc;
342 	else if (args.rets[0])
343 		return args.rets[0];
344 
345 	post_mobility_fixup();
346 	return count;
347 }
348 
349 static CLASS_ATTR(migration, S_IWUSR, NULL, migrate_store);
350 
351 static int __init mobility_sysfs_init(void)
352 {
353 	int rc;
354 
355 	mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
356 	if (!mobility_kobj)
357 		return -ENOMEM;
358 
359 	rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
360 
361 	return rc;
362 }
363 device_initcall(mobility_sysfs_init);
364