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/machdep.h>
  22 #include <asm/rtas.h>
  23 #include "pseries.h"
  24
  25 static struct kobject *mobility_kobj;
  26
  27 struct update_props_workarea {
  28         __be32 phandle;
  29         __be32 state;
  30         __be64 reserved;
  31         __be32 nprops;
  32 } __packed;
  33
  34 #define NODE_ACTION_MASK        0xff000000
  35 #define NODE_COUNT_MASK         0x00ffffff
  36
  37 #define DELETE_DT_NODE  0x01000000
  38 #define UPDATE_DT_NODE  0x02000000
  39 #define ADD_DT_NODE     0x03000000
  40
  41 #define MIGRATION_SCOPE (1)
  42 #define PRRN_SCOPE -2
  43
  44 static int mobility_rtas_call(int token, char *buf, s32 scope)
  45 {
  46         int rc;
  47
  48         spin_lock(&rtas_data_buf_lock);
  49
  50         memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
  51         rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
  52         memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
  53
  54         spin_unlock(&rtas_data_buf_lock);
  55         return rc;
  56 }
  57
  58 static int delete_dt_node(__be32 phandle)
  59 {
  60         struct device_node *dn;
  61
  62         dn = of_find_node_by_phandle(be32_to_cpu(phandle));
  63         if (!dn)
  64                 return -ENOENT;
  65
  66         dlpar_detach_node(dn);
  67         of_node_put(dn);
  68         return 0;
  69 }
  70
  71 static int update_dt_property(struct device_node *dn, struct property **prop,
  72                               const char *name, u32 vd, char *value)
  73 {
  74         struct property *new_prop = *prop;
  75         int more = 0;
  76
  77         /* A negative 'vd' value indicates that only part of the new property
  78          * value is contained in the buffer and we need to call
  79          * ibm,update-properties again to get the rest of the value.
  80          *
  81          * A negative value is also the two's compliment of the actual value.
  82          */
  83         if (vd & 0x80000000) {
  84                 vd = ~vd + 1;
  85                 more = 1;
  86         }
  87
  88         if (new_prop) {
  89                 /* partial property fixup */
  90                 char *new_data = kzalloc(new_prop->length + vd, GFP_KERNEL);
  91                 if (!new_data)
  92                         return -ENOMEM;
  93
  94                 memcpy(new_data, new_prop->value, new_prop->length);
  95                 memcpy(new_data + new_prop->length, value, vd);
  96
  97                 kfree(new_prop->value);
  98                 new_prop->value = new_data;
  99                 new_prop->length += vd;
 100         } else {
 101                 new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
 102                 if (!new_prop)
 103                         return -ENOMEM;
 104
 105                 new_prop->name = kstrdup(name, GFP_KERNEL);
 106                 if (!new_prop->name) {
 107                         kfree(new_prop);
 108                         return -ENOMEM;
 109                 }
 110
 111                 new_prop->length = vd;
 112                 new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
 113                 if (!new_prop->value) {
 114                         kfree(new_prop->name);
 115                         kfree(new_prop);
 116                         return -ENOMEM;
 117                 }
 118
 119                 memcpy(new_prop->value, value, vd);
 120                 *prop = new_prop;
 121         }
 122
 123         if (!more) {
 124                 of_update_property(dn, new_prop);
 125                 *prop = NULL;
 126         }
 127
 128         return 0;
 129 }
 130
 131 static int update_dt_node(__be32 phandle, s32 scope)
 132 {
 133         struct update_props_workarea *upwa;
 134         struct device_node *dn;
 135         struct property *prop = NULL;
 136         int i, rc, rtas_rc;
 137         char *prop_data;
 138         char *rtas_buf;
 139         int update_properties_token;
 140         u32 nprops;
 141         u32 vd;
 142
 143         update_properties_token = rtas_token("ibm,update-properties");
 144         if (update_properties_token == RTAS_UNKNOWN_SERVICE)
 145                 return -EINVAL;
 146
 147         rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 148         if (!rtas_buf)
 149                 return -ENOMEM;
 150
 151         dn = of_find_node_by_phandle(be32_to_cpu(phandle));
 152         if (!dn) {
 153                 kfree(rtas_buf);
 154                 return -ENOENT;
 155         }
 156
 157         upwa = (struct update_props_workarea *)&rtas_buf[0];
 158         upwa->phandle = phandle;
 159
 160         do {
 161                 rtas_rc = mobility_rtas_call(update_properties_token, rtas_buf,
 162                                         scope);
 163                 if (rtas_rc < 0)
 164                         break;
 165
 166                 prop_data = rtas_buf + sizeof(*upwa);
 167                 nprops = be32_to_cpu(upwa->nprops);
 168
 169                 /* On the first call to ibm,update-properties for a node the
 170                  * the first property value descriptor contains an empty
 171                  * property name, the property value length encoded as u32,
 172                  * and the property value is the node path being updated.
 173                  */
 174                 if (*prop_data == 0) {
 175                         prop_data++;
 176                         vd = be32_to_cpu(*(__be32 *)prop_data);
 177                         prop_data += vd + sizeof(vd);
 178                         nprops--;
 179                 }
 180
 181                 for (i = 0; i < nprops; i++) {
 182                         char *prop_name;
 183
 184                         prop_name = prop_data;
 185                         prop_data += strlen(prop_name) + 1;
 186                         vd = be32_to_cpu(*(__be32 *)prop_data);
 187                         prop_data += sizeof(vd);
 188
 189                         switch (vd) {
 190                         case 0x00000000:
 191                                 /* name only property, nothing to do */
 192                                 break;
 193
 194                         case 0x80000000:
 195                                 of_remove_property(dn, of_find_property(dn,
 196                                                         prop_name, NULL));
 197                                 prop = NULL;
 198                                 break;
 199
 200                         default:
 201                                 rc = update_dt_property(dn, &prop, prop_name,
 202                                                         vd, prop_data);
 203                                 if (rc) {
 204                                         printk(KERN_ERR "Could not update %s"
 205                                                " property\n", prop_name);
 206                                 }
 207
 208                                 prop_data += vd;
 209                         }
 210                 }
 211         } while (rtas_rc == 1);
 212
 213         of_node_put(dn);
 214         kfree(rtas_buf);
 215         return 0;
 216 }
 217
 218 static int add_dt_node(__be32 parent_phandle, __be32 drc_index)
 219 {
 220         struct device_node *dn;
 221         struct device_node *parent_dn;
 222         int rc;
 223
 224         parent_dn = of_find_node_by_phandle(be32_to_cpu(parent_phandle));
 225         if (!parent_dn)
 226                 return -ENOENT;
 227
 228         dn = dlpar_configure_connector(drc_index, parent_dn);
 229         if (!dn) {
 230                 of_node_put(parent_dn);
 231                 return -ENOENT;
 232         }
 233
 234         rc = dlpar_attach_node(dn, parent_dn);
 235         if (rc)
 236                 dlpar_free_cc_nodes(dn);
 237
 238         of_node_put(parent_dn);
 239         return rc;
 240 }
 241
 242 static void prrn_update_node(__be32 phandle)
 243 {
 244         struct pseries_hp_errorlog *hp_elog;
 245         struct device_node *dn;
 246
 247         /*
 248          * If a node is found from a the given phandle, the phandle does not
 249          * represent the drc index of an LMB and we can ignore.
 250          */
 251         dn = of_find_node_by_phandle(be32_to_cpu(phandle));
 252         if (dn) {
 253                 of_node_put(dn);
 254                 return;
 255         }
 256
 257         hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
 258         if(!hp_elog)
 259                 return;
 260
 261         hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
 262         hp_elog->action = PSERIES_HP_ELOG_ACTION_READD;
 263         hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
 264         hp_elog->_drc_u.drc_index = phandle;
 265
 266         queue_hotplug_event(hp_elog, NULL, NULL);
 267
 268         kfree(hp_elog);
 269 }
 270
 271 int pseries_devicetree_update(s32 scope)
 272 {
 273         char *rtas_buf;
 274         __be32 *data;
 275         int update_nodes_token;
 276         int rc;
 277
 278         update_nodes_token = rtas_token("ibm,update-nodes");
 279         if (update_nodes_token == RTAS_UNKNOWN_SERVICE)
 280                 return -EINVAL;
 281
 282         rtas_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 283         if (!rtas_buf)
 284                 return -ENOMEM;
 285
 286         do {
 287                 rc = mobility_rtas_call(update_nodes_token, rtas_buf, scope);
 288                 if (rc && rc != 1)
 289                         break;
 290
 291                 data = (__be32 *)rtas_buf + 4;
 292                 while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
 293                         int i;
 294                         u32 action = be32_to_cpu(*data) & NODE_ACTION_MASK;
 295                         u32 node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;
 296
 297                         data++;
 298
 299                         for (i = 0; i < node_count; i++) {
 300                                 __be32 phandle = *data++;
 301                                 __be32 drc_index;
 302
 303                                 switch (action) {
 304                                 case DELETE_DT_NODE:
 305                                         delete_dt_node(phandle);
 306                                         break;
 307                                 case UPDATE_DT_NODE:
 308                                         update_dt_node(phandle, scope);
 309
 310                                         if (scope == PRRN_SCOPE)
 311                                                 prrn_update_node(phandle);
 312
 313                                         break;
 314                                 case ADD_DT_NODE:
 315                                         drc_index = *data++;
 316                                         add_dt_node(phandle, drc_index);
 317                                         break;
 318                                 }
 319                         }
 320                 }
 321         } while (rc == 1);
 322
 323         kfree(rtas_buf);
 324         return rc;
 325 }
 326
 327 void post_mobility_fixup(void)
 328 {
 329         int rc;
 330         int activate_fw_token;
 331
 332         activate_fw_token = rtas_token("ibm,activate-firmware");
 333         if (activate_fw_token == RTAS_UNKNOWN_SERVICE) {
 334                 printk(KERN_ERR "Could not make post-mobility "
 335                        "activate-fw call.\n");
 336                 return;
 337         }
 338
 339         do {
 340                 rc = rtas_call(activate_fw_token, 0, 1, NULL);
 341         } while (rtas_busy_delay(rc));
 342
 343         if (rc)
 344                 printk(KERN_ERR "Post-mobility activate-fw failed: %d\n", rc);
 345
 346         rc = pseries_devicetree_update(MIGRATION_SCOPE);
 347         if (rc)
 348                 printk(KERN_ERR "Post-mobility device tree update "
 349                         "failed: %d\n", rc);
 350
 351         return;
 352 }
 353
 354 static ssize_t migration_store(struct class *class,
 355                                struct class_attribute *attr, const char *buf,
 356                                size_t count)
 357 {
 358         u64 streamid;
 359         int rc;
 360
 361         rc = kstrtou64(buf, 0, &streamid);
 362         if (rc)
 363                 return rc;
 364
 365         do {
 366                 rc = rtas_ibm_suspend_me(streamid);
 367                 if (rc == -EAGAIN)
 368                         ssleep(1);
 369         } while (rc == -EAGAIN);
 370
 371         if (rc)
 372                 return rc;
 373
 374         post_mobility_fixup();
 375         return count;
 376 }
 377
 378 /*
 379  * Used by drmgr to determine the kernel behavior of the migration interface.
 380  *
 381  * Version 1: Performs all PAPR requirements for migration including
 382  *      firmware activation and device tree update.
 383  */
 384 #define MIGRATION_API_VERSION   1
 385
 386 static CLASS_ATTR_WO(migration);
 387 static CLASS_ATTR_STRING(api_version, S_IRUGO, __stringify(MIGRATION_API_VERSION));
 388
 389 static int __init mobility_sysfs_init(void)
 390 {
 391         int rc;
 392
 393         mobility_kobj = kobject_create_and_add("mobility", kernel_kobj);
 394         if (!mobility_kobj)
 395                 return -ENOMEM;
 396
 397         rc = sysfs_create_file(mobility_kobj, &class_attr_migration.attr);
 398         if (rc)
 399                 pr_err("mobility: unable to create migration sysfs file (%d)\n", rc);
 400
 401         rc = sysfs_create_file(mobility_kobj, &class_attr_api_version.attr.attr);
 402         if (rc)
 403                 pr_err("mobility: unable to create api_version sysfs file (%d)\n", rc);
 404
 405         return 0;
 406 }
 407 machine_device_initcall(pseries, mobility_sysfs_init);