xref: /linux/arch/powerpc/platforms/pseries/mobility.c (revision 67577927e8d7a1f4b09b4992df640eadc6aacb36)
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/completion.h>
16 #include <linux/device.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 
20 #include <asm/rtas.h>
21 #include "pseries.h"
22 
23 static struct kobject *mobility_kobj;
24 
25 struct update_props_workarea {
26 	u32 phandle;
27 	u32 state;
28 	u64 reserved;
29 	u32 nprops;
30 };
31 
32 #define NODE_ACTION_MASK	0xff000000
33 #define NODE_COUNT_MASK		0x00ffffff
34 
35 #define DELETE_DT_NODE	0x01000000
36 #define UPDATE_DT_NODE	0x02000000
37 #define ADD_DT_NODE	0x03000000
38 
39 static int mobility_rtas_call(int token, char *buf)
40 {
41 	int rc;
42 
43 	spin_lock(&rtas_data_buf_lock);
44 
45 	memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
46 	rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, 1);
47 	memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
48 
49 	spin_unlock(&rtas_data_buf_lock);
50 	return rc;
51 }
52 
53 static int delete_dt_node(u32 phandle)
54 {
55 	struct device_node *dn;
56 
57 	dn = of_find_node_by_phandle(phandle);
58 	if (!dn)
59 		return -ENOENT;
60 
61 	dlpar_detach_node(dn);
62 	return 0;
63 }
64 
65 static int update_dt_property(struct device_node *dn, struct property **prop,
66 			      const char *name, u32 vd, char *value)
67 {
68 	struct property *new_prop = *prop;
69 	struct property *old_prop;
70 	int more = 0;
71 
72 	/* A negative 'vd' value indicates that only part of the new property
73 	 * value is contained in the buffer and we need to call
74 	 * ibm,update-properties again to get the rest of the value.
75 	 *
76 	 * A negative value is also the two's compliment of the actual value.
77 	 */
78 	if (vd & 0x80000000) {
79 		vd = ~vd + 1;
80 		more = 1;
81 	}
82 
83 	if (new_prop) {
84 		/* partial property fixup */
85 		char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
86 		if (!new_data)
87 			return -ENOMEM;
88 
89 		memcpy(new_data, new_prop->value, new_prop->length);
90 		memcpy(new_data + new_prop->length, value, vd);
91 
92 		kfree(new_prop->value);
93 		new_prop->value = new_data;
94 		new_prop->length += vd;
95 	} else {
96 		new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
97 		if (!new_prop)
98 			return -ENOMEM;
99 
100 		new_prop->name = kstrdup(name, GFP_KERNEL);
101 		if (!new_prop->name) {
102 			kfree(new_prop);
103 			return -ENOMEM;
104 		}
105 
106 		new_prop->length = vd;
107 		new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
108 		if (!new_prop->value) {
109 			kfree(new_prop->name);
110 			kfree(new_prop);
111 			return -ENOMEM;
112 		}
113 
114 		memcpy(new_prop->value, value, vd);
115 		*prop = new_prop;
116 	}
117 
118 	if (!more) {
119 		old_prop = of_find_property(dn, new_prop->name, NULL);
120 		if (old_prop)
121 			prom_update_property(dn, new_prop, old_prop);
122 		else
123 			prom_add_property(dn, new_prop);
124 
125 		new_prop = NULL;
126 	}
127 
128 	return 0;
129 }
130 
131 static int update_dt_node(u32 phandle)
132 {
133 	struct update_props_workarea *upwa;
134 	struct device_node *dn;
135 	struct property *prop = NULL;
136 	int i, rc;
137 	char *prop_data;
138 	char *rtas_buf;
139 	int update_properties_token;
140 
141 	update_properties_token = rtas_token("ibm,update-properties");
142 	if (update_properties_token == RTAS_UNKNOWN_SERVICE)
143 		return -EINVAL;
144 
145 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
146 	if (!rtas_buf)
147 		return -ENOMEM;
148 
149 	dn = of_find_node_by_phandle(phandle);
150 	if (!dn) {
151 		kfree(rtas_buf);
152 		return -ENOENT;
153 	}
154 
155 	upwa = (struct update_props_workarea *)&rtas_buf[0];
156 	upwa->phandle = phandle;
157 
158 	do {
159 		rc = mobility_rtas_call(update_properties_token, rtas_buf);
160 		if (rc < 0)
161 			break;
162 
163 		prop_data = rtas_buf + sizeof(*upwa);
164 
165 		for (i = 0; i < upwa->nprops; i++) {
166 			char *prop_name;
167 			u32 vd;
168 
169 			prop_name = prop_data + 1;
170 			prop_data += strlen(prop_name) + 1;
171 			vd = *prop_data++;
172 
173 			switch (vd) {
174 			case 0x00000000:
175 				/* name only property, nothing to do */
176 				break;
177 
178 			case 0x80000000:
179 				prop = of_find_property(dn, prop_name, NULL);
180 				prom_remove_property(dn, prop);
181 				prop = NULL;
182 				break;
183 
184 			default:
185 				rc = update_dt_property(dn, &prop, prop_name,
186 							vd, prop_data);
187 				if (rc) {
188 					printk(KERN_ERR "Could not update %s"
189 					       " property\n", prop_name);
190 				}
191 
192 				prop_data += vd;
193 			}
194 		}
195 	} while (rc == 1);
196 
197 	of_node_put(dn);
198 	kfree(rtas_buf);
199 	return 0;
200 }
201 
202 static int add_dt_node(u32 parent_phandle, u32 drc_index)
203 {
204 	struct device_node *dn;
205 	struct device_node *parent_dn;
206 	int rc;
207 
208 	dn = dlpar_configure_connector(drc_index);
209 	if (!dn)
210 		return -ENOENT;
211 
212 	parent_dn = of_find_node_by_phandle(parent_phandle);
213 	if (!parent_dn) {
214 		dlpar_free_cc_nodes(dn);
215 		return -ENOENT;
216 	}
217 
218 	dn->parent = parent_dn;
219 	rc = dlpar_attach_node(dn);
220 	if (rc)
221 		dlpar_free_cc_nodes(dn);
222 
223 	of_node_put(parent_dn);
224 	return rc;
225 }
226 
227 static int pseries_devicetree_update(void)
228 {
229 	char *rtas_buf;
230 	u32 *data;
231 	int update_nodes_token;
232 	int rc;
233 
234 	update_nodes_token = rtas_token("ibm,update-nodes");
235 	if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
236 		return -EINVAL;
237 
238 	rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
239 	if (!rtas_buf)
240 		return -ENOMEM;
241 
242 	do {
243 		rc = mobility_rtas_call(update_nodes_token, rtas_buf);
244 		if (rc && rc != 1)
245 			break;
246 
247 		data = (u32 *)rtas_buf + 4;
248 		while (*data & NODE_ACTION_MASK) {
249 			int i;
250 			u32 action = *data & NODE_ACTION_MASK;
251 			int node_count = *data & NODE_COUNT_MASK;
252 
253 			data++;
254 
255 			for (i = 0; i < node_count; i++) {
256 				u32 phandle = *data++;
257 				u32 drc_index;
258 
259 				switch (action) {
260 				case DELETE_DT_NODE:
261 					delete_dt_node(phandle);
262 					break;
263 				case UPDATE_DT_NODE:
264 					update_dt_node(phandle);
265 					break;
266 				case ADD_DT_NODE:
267 					drc_index = *data++;
268 					add_dt_node(phandle, drc_index);
269 					break;
270 				}
271 			}
272 		}
273 	} while (rc == 1);
274 
275 	kfree(rtas_buf);
276 	return rc;
277 }
278 
279 void post_mobility_fixup(void)
280 {
281 	int rc;
282 	int activate_fw_token;
283 
284 	rc = pseries_devicetree_update();
285 	if (rc) {
286 		printk(KERN_ERR "Initial post-mobility device tree update "
287 		       "failed: %d\n", rc);
288 		return;
289 	}
290 
291 	activate_fw_token = rtas_token("ibm,activate-firmware");
292 	if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
293 		printk(KERN_ERR "Could not make post-mobility "
294 		       "activate-fw call.\n");
295 		return;
296 	}
297 
298 	rc = rtas_call(activate_fw_token, 0, 1, NULL);
299 	if (!rc) {
300 		rc = pseries_devicetree_update();
301 		if (rc)
302 			printk(KERN_ERR "Secondary post-mobility device tree "
303 			       "update failed: %d\n", rc);
304 	} else {
305 		printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);
306 		return;
307 	}
308 
309 	return;
310 }
311 
312 static ssize_t migrate_store(struct class *class, struct class_attribute *attr,
313 			     const char *buf, size_t count)
314 {
315 	struct rtas_args args;
316 	u64 streamid;
317 	int rc;
318 
319 	rc = strict_strtoull(buf, 0, &streamid);
320 	if (rc)
321 		return rc;
322 
323 	memset(&args, 0, sizeof(args));
324 	args.token = rtas_token("ibm,suspend-me");
325 	args.nargs = 2;
326 	args.nret = 1;
327 
328 	args.args[0] = streamid >> 32 ;
329 	args.args[1] = streamid & 0xffffffff;
330 	args.rets = &args.args[args.nargs];
331 
332 	do {
333 		args.rets[0] = 0;
334 		rc = rtas_ibm_suspend_me(&args);
335 		if (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE)
336 			ssleep(1);
337 	} while (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE);
338 
339 	if (rc)
340 		return rc;
341 	else if (args.rets[0])
342 		return args.rets[0];
343 
344 	post_mobility_fixup();
345 	return count;
346 }
347 
348 static CLASS_ATTR(migration, S_IWUSR, NULL, migrate_store);
349 
350 static int __init mobility_sysfs_init(void)
351 {
352 	int rc;
353 
354 	mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
355 	if (!mobility_kobj)
356 		return -ENOMEM;
357 
358 	rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
359 
360 	return rc;
361 }
362 device_initcall(mobility_sysfs_init);
363