arch/powerpc/platforms/pseries/mobility.c

   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 #define MIGRATION_SCOPE (1)
  41
  42 static int mobility_rtas_call(int token, char *buf, s32 scope)
  43 {
  44         int rc;
  45
  46         spin_lock(&rtas_data_buf_lock);
  47
  48         memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
  49         rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
  50         memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
  51
  52         spin_unlock(&rtas_data_buf_lock);
  53         return rc;
  54 }
  55
  56 static int delete_dt_node(u32 phandle)
  57 {
  58         struct device_node *dn;
  59
  60         dn = of_find_node_by_phandle(phandle);
  61         if (!dn)
  62                 return -ENOENT;
  63
  64         dlpar_detach_node(dn);
  65         return 0;
  66 }
  67
  68 static int update_dt_property(struct device_node *dn, struct property **prop,
  69                               const char *name, u32 vd, char *value)
  70 {
  71         struct property *new_prop = *prop;
  72         int more = 0;
  73
  74         /* A negative 'vd' value indicates that only part of the new property
  75          * value is contained in the buffer and we need to call
  76          * ibm,update-properties again to get the rest of the value.
  77          *
  78          * A negative value is also the two's compliment of the actual value.
  79          */
  80         if (vd & 0x80000000) {
  81                 vd = ~vd + 1;
  82                 more = 1;
  83         }
  84
  85         if (new_prop) {
  86                 /* partial property fixup */
  87                 char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
  88                 if (!new_data)
  89                         return -ENOMEM;
  90
  91                 memcpy(new_data, new_prop->value, new_prop->length);
  92                 memcpy(new_data + new_prop->length, value, vd);
  93
  94                 kfree(new_prop->value);
  95                 new_prop->value = new_data;
  96                 new_prop->length += vd;
  97         } else {
  98                 new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
  99                 if (!new_prop)
 100                         return -ENOMEM;
 101
 102                 new_prop->name = kstrdup(name, GFP_KERNEL);
 103                 if (!new_prop->name) {
 104                         kfree(new_prop);
 105                         return -ENOMEM;
 106                 }
 107
 108                 new_prop->length = vd;
 109                 new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
 110                 if (!new_prop->value) {
 111                         kfree(new_prop->name);
 112                         kfree(new_prop);
 113                         return -ENOMEM;
 114                 }
 115
 116                 memcpy(new_prop->value, value, vd);
 117                 *prop = new_prop;
 118         }
 119
 120         if (!more) {
 121                 of_update_property(dn, new_prop);
 122                 new_prop = NULL;
 123         }
 124
 125         return 0;
 126 }
 127
 128 static int update_dt_node(u32 phandle, s32 scope)
 129 {
 130         struct update_props_workarea *upwa;
 131         struct device_node *dn;
 132         struct property *prop = NULL;
 133         int i, rc;
 134         char *prop_data;
 135         char *rtas_buf;
 136         int update_properties_token;
 137         u32 vd;
 138
 139         update_properties_token = rtas_token("ibm,update-properties");
 140         if (update_properties_token == RTAS_UNKNOWN_SERVICE)
 141                 return -EINVAL;
 142
 143         rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 144         if (!rtas_buf)
 145                 return -ENOMEM;
 146
 147         dn = of_find_node_by_phandle(phandle);
 148         if (!dn) {
 149                 kfree(rtas_buf);
 150                 return -ENOENT;
 151         }
 152
 153         upwa = (struct update_props_workarea *)&rtas_buf[0];
 154         upwa->phandle = phandle;
 155
 156         do {
 157                 rc = mobility_rtas_call(update_properties_token, rtas_buf,
 158                                         scope);
 159                 if (rc < 0)
 160                         break;
 161
 162                 prop_data = rtas_buf + sizeof(*upwa);
 163
 164                 /* The first element of the buffer is the path of the node
 165                  * being updated in the form of a 8 byte string length
 166                  * followed by the string. Skip past this to get to the
 167                  * properties being updated.
 168                  */
 169                 vd = *prop_data++;
 170                 prop_data += vd;
 171
 172                 /* The path we skipped over is counted as one of the elements
 173                  * returned so start counting at one.
 174                  */
 175                 for (i = 1; i < upwa->nprops; i++) {
 176                         char *prop_name;
 177
 178                         prop_name = prop_data;
 179                         prop_data += strlen(prop_name) + 1;
 180                         vd = *(u32 *)prop_data;
 181                         prop_data += sizeof(vd);
 182
 183                         switch (vd) {
 184                         case 0x00000000:
 185                                 /* name only property, nothing to do */
 186                                 break;
 187
 188                         case 0x80000000:
 189                                 prop = of_find_property(dn, prop_name, NULL);
 190                                 of_remove_property(dn, prop);
 191                                 prop = NULL;
 192                                 break;
 193
 194                         default:
 195                                 rc = update_dt_property(dn, &prop, prop_name,
 196                                                         vd, prop_data);
 197                                 if (rc) {
 198                                         printk(KERN_ERR "Could not update %s"
 199                                                " property\n", prop_name);
 200                                 }
 201
 202                                 prop_data += vd;
 203                         }
 204                 }
 205         } while (rc == 1);
 206
 207         of_node_put(dn);
 208         kfree(rtas_buf);
 209         return 0;
 210 }
 211
 212 static int add_dt_node(u32 parent_phandle, u32 drc_index)
 213 {
 214         struct device_node *dn;
 215         struct device_node *parent_dn;
 216         int rc;
 217
 218         dn = dlpar_configure_connector(drc_index);
 219         if (!dn)
 220                 return -ENOENT;
 221
 222         parent_dn = of_find_node_by_phandle(parent_phandle);
 223         if (!parent_dn) {
 224                 dlpar_free_cc_nodes(dn);
 225                 return -ENOENT;
 226         }
 227
 228         dn->parent = parent_dn;
 229         rc = dlpar_attach_node(dn);
 230         if (rc)
 231                 dlpar_free_cc_nodes(dn);
 232
 233         of_node_put(parent_dn);
 234         return rc;
 235 }
 236
 237 int pseries_devicetree_update(s32 scope)
 238 {
 239         char *rtas_buf;
 240         u32 *data;
 241         int update_nodes_token;
 242         int rc;
 243
 244         update_nodes_token = rtas_token("ibm,update-nodes");
 245         if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
 246                 return -EINVAL;
 247
 248         rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 249         if (!rtas_buf)
 250                 return -ENOMEM;
 251
 252         do {
 253                 rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
 254                 if (rc && rc != 1)
 255                         break;
 256
 257                 data = (u32 *)rtas_buf + 4;
 258                 while (*data & NODE_ACTION_MASK) {
 259                         int i;
 260                         u32 action = *data & NODE_ACTION_MASK;
 261                         int node_count = *data & NODE_COUNT_MASK;
 262
 263                         data++;
 264
 265                         for (i = 0; i < node_count; i++) {
 266                                 u32 phandle = *data++;
 267                                 u32 drc_index;
 268
 269                                 switch (action) {
 270                                 case DELETE_DT_NODE:
 271                                         delete_dt_node(phandle);
 272                                         break;
 273                                 case UPDATE_DT_NODE:
 274                                         update_dt_node(phandle, scope);
 275                                         break;
 276                                 case ADD_DT_NODE:
 277                                         drc_index = *data++;
 278                                         add_dt_node(phandle, drc_index);
 279                                         break;
 280                                 }
 281                         }
 282                 }
 283         } while (rc == 1);
 284
 285         kfree(rtas_buf);
 286         return rc;
 287 }
 288
 289 void post_mobility_fixup(void)
 290 {
 291         int rc;
 292         int activate_fw_token;
 293
 294         rc = pseries_devicetree_update(MIGRATION_SCOPE);
 295         if (rc) {
 296                 printk(KERN_ERR "Initial post-mobility device tree update "
 297                        "failed: %d\n", rc);
 298                 return;
 299         }
 300
 301         activate_fw_token = rtas_token("ibm,activate-firmware");
 302         if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
 303                 printk(KERN_ERR "Could not make post-mobility "
 304                        "activate-fw call.\n");
 305                 return;
 306         }
 307
 308         rc = rtas_call(activate_fw_token, 0, 1, NULL);
 309         if (!rc) {
 310                 rc = pseries_devicetree_update(MIGRATION_SCOPE);
 311                 if (rc)
 312                         printk(KERN_ERR "Secondary post-mobility device tree "
 313                                "update failed: %d\n", rc);
 314         } else {
 315                 printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);
 316                 return;
 317         }
 318
 319         return;
 320 }
 321
 322 static ssize_t migrate_store(struct class *class, struct class_attribute *attr,
 323                              const char *buf, size_t count)
 324 {
 325         struct rtas_args args;
 326         u64 streamid;
 327         int rc;
 328
 329         rc = strict_strtoull(buf, 0, &streamid);
 330         if (rc)
 331                 return rc;
 332
 333         memset(&args, 0, sizeof(args));
 334         args.token = rtas_token("ibm,suspend-me");
 335         args.nargs = 2;
 336         args.nret = 1;
 337
 338         args.args[0] = streamid >> 32 ;
 339         args.args[1] = streamid & 0xffffffff;
 340         args.rets = &args.args[args.nargs];
 341
 342         do {
 343                 args.rets[0] = 0;
 344                 rc = rtas_ibm_suspend_me(&args);
 345                 if (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE)
 346                         ssleep(1);
 347         } while (!rc && args.rets[0] == RTAS_NOT_SUSPENDABLE);
 348
 349         if (rc)
 350                 return rc;
 351         else if (args.rets[0])
 352                 return args.rets[0];
 353
 354         post_mobility_fixup();
 355         return count;
 356 }
 357
 358 static CLASS_ATTR(migration, S_IWUSR, NULL, migrate_store);
 359
 360 static int __init mobility_sysfs_init(void)
 361 {
 362         int rc;
 363
 364         mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
 365         if (!mobility_kobj)
 366                 return -ENOMEM;
 367
 368         rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
 369
 370         return rc;
 371 }
 372 device_initcall(mobility_sysfs_init);