arch/powerpc/platforms/pseries/hotplug-memory.c

   1 /*
   2  * pseries Memory Hotplug infrastructure.
   3  *
   4  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
  13
  14 #include <linux/of.h>
  15 #include <linux/of_address.h>
  16 #include <linux/memblock.h>
  17 #include <linux/memory.h>
  18 #include <linux/memory_hotplug.h>
  19 #include <linux/slab.h>
  20
  21 #include <asm/firmware.h>
  22 #include <asm/machdep.h>
  23 #include <asm/prom.h>
  24 #include <asm/sparsemem.h>
  25 #include "pseries.h"
  26
  27 static bool rtas_hp_event;
  28
  29 unsigned long pseries_memory_block_size(void)
  30 {
  31         struct device_node *np;
  32         unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
  33         struct resource r;
  34
  35         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
  36         if (np) {
  37                 const __be64 *size;
  38
  39                 size = of_get_property(np, "ibm,lmb-size", NULL);
  40                 if (size)
  41                         memblock_size = be64_to_cpup(size);
  42                 of_node_put(np);
  43         } else  if (machine_is(pseries)) {
  44                 /* This fallback really only applies to pseries */
  45                 unsigned int memzero_size = 0;
  46
  47                 np = of_find_node_by_path("/memory@0");
  48                 if (np) {
  49                         if (!of_address_to_resource(np, 0, &r))
  50                                 memzero_size = resource_size(&r);
  51                         of_node_put(np);
  52                 }
  53
  54                 if (memzero_size) {
  55                         /* We now know the size of memory@0, use this to find
  56                          * the first memoryblock and get its size.
  57                          */
  58                         char buf[64];
  59
  60                         sprintf(buf, "/memory@%x", memzero_size);
  61                         np = of_find_node_by_path(buf);
  62                         if (np) {
  63                                 if (!of_address_to_resource(np, 0, &r))
  64                                         memblock_size = resource_size(&r);
  65                                 of_node_put(np);
  66                         }
  67                 }
  68         }
  69         return memblock_size;
  70 }
  71
  72 static void dlpar_free_drconf_property(struct property *prop)
  73 {
  74         kfree(prop->name);
  75         kfree(prop->value);
  76         kfree(prop);
  77 }
  78
  79 static struct property *dlpar_clone_drconf_property(struct device_node *dn)
  80 {
  81         struct property *prop, *new_prop;
  82         struct of_drconf_cell *lmbs;
  83         u32 num_lmbs, *p;
  84         int i;
  85
  86         prop = of_find_property(dn, "ibm,dynamic-memory", NULL);
  87         if (!prop)
  88                 return NULL;
  89
  90         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
  91         if (!new_prop)
  92                 return NULL;
  93
  94         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
  95         new_prop->value = kmalloc(prop->length, GFP_KERNEL);
  96         if (!new_prop->name || !new_prop->value) {
  97                 dlpar_free_drconf_property(new_prop);
  98                 return NULL;
  99         }
 100
 101         memcpy(new_prop->value, prop->value, prop->length);
 102         new_prop->length = prop->length;
 103
 104         /* Convert the property to cpu endian-ness */
 105         p = new_prop->value;
 106         *p = be32_to_cpu(*p);
 107
 108         num_lmbs = *p++;
 109         lmbs = (struct of_drconf_cell *)p;
 110
 111         for (i = 0; i < num_lmbs; i++) {
 112                 lmbs[i].base_addr = be64_to_cpu(lmbs[i].base_addr);
 113                 lmbs[i].drc_index = be32_to_cpu(lmbs[i].drc_index);
 114                 lmbs[i].flags = be32_to_cpu(lmbs[i].flags);
 115         }
 116
 117         return new_prop;
 118 }
 119
 120 static struct memory_block *lmb_to_memblock(struct of_drconf_cell *lmb)
 121 {
 122         unsigned long section_nr;
 123         struct mem_section *mem_sect;
 124         struct memory_block *mem_block;
 125
 126         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 127         mem_sect = __nr_to_section(section_nr);
 128
 129         mem_block = find_memory_block(mem_sect);
 130         return mem_block;
 131 }
 132
 133 #ifdef CONFIG_MEMORY_HOTREMOVE
 134 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 135 {
 136         unsigned long block_sz, start_pfn;
 137         int sections_per_block;
 138         int i, nid;
 139
 140         start_pfn = base >> PAGE_SHIFT;
 141
 142         lock_device_hotplug();
 143
 144         if (!pfn_valid(start_pfn))
 145                 goto out;
 146
 147         block_sz = pseries_memory_block_size();
 148         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 149         nid = memory_add_physaddr_to_nid(base);
 150
 151         for (i = 0; i < sections_per_block; i++) {
 152                 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
 153                 base += MIN_MEMORY_BLOCK_SIZE;
 154         }
 155
 156 out:
 157         /* Update memory regions for memory remove */
 158         memblock_remove(base, memblock_size);
 159         unlock_device_hotplug();
 160         return 0;
 161 }
 162
 163 static int pseries_remove_mem_node(struct device_node *np)
 164 {
 165         const char *type;
 166         const __be32 *regs;
 167         unsigned long base;
 168         unsigned int lmb_size;
 169         int ret = -EINVAL;
 170
 171         /*
 172          * Check to see if we are actually removing memory
 173          */
 174         type = of_get_property(np, "device_type", NULL);
 175         if (type == NULL || strcmp(type, "memory") != 0)
 176                 return 0;
 177
 178         /*
 179          * Find the base address and size of the memblock
 180          */
 181         regs = of_get_property(np, "reg", NULL);
 182         if (!regs)
 183                 return ret;
 184
 185         base = be64_to_cpu(*(unsigned long *)regs);
 186         lmb_size = be32_to_cpu(regs[3]);
 187
 188         pseries_remove_memblock(base, lmb_size);
 189         return 0;
 190 }
 191 #else
 192 static inline int pseries_remove_memblock(unsigned long base,
 193                                           unsigned int memblock_size)
 194 {
 195         return -EOPNOTSUPP;
 196 }
 197 static inline int pseries_remove_mem_node(struct device_node *np)
 198 {
 199         return 0;
 200 }
 201 #endif /* CONFIG_MEMORY_HOTREMOVE */
 202
 203 static int dlpar_add_lmb(struct of_drconf_cell *lmb)
 204 {
 205         struct memory_block *mem_block;
 206         unsigned long block_sz;
 207         int nid, rc;
 208
 209         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 210                 return -EINVAL;
 211
 212         block_sz = memory_block_size_bytes();
 213
 214         rc = dlpar_acquire_drc(lmb->drc_index);
 215         if (rc)
 216                 return rc;
 217
 218         /* Find the node id for this address */
 219         nid = memory_add_physaddr_to_nid(lmb->base_addr);
 220
 221         /* Add the memory */
 222         rc = add_memory(nid, lmb->base_addr, block_sz);
 223         if (rc) {
 224                 dlpar_release_drc(lmb->drc_index);
 225                 return rc;
 226         }
 227
 228         /* Register this block of memory */
 229         rc = memblock_add(lmb->base_addr, block_sz);
 230         if (rc) {
 231                 remove_memory(nid, lmb->base_addr, block_sz);
 232                 dlpar_release_drc(lmb->drc_index);
 233                 return rc;
 234         }
 235
 236         mem_block = lmb_to_memblock(lmb);
 237         if (!mem_block) {
 238                 remove_memory(nid, lmb->base_addr, block_sz);
 239                 dlpar_release_drc(lmb->drc_index);
 240                 return -EINVAL;
 241         }
 242
 243         rc = device_online(&mem_block->dev);
 244         put_device(&mem_block->dev);
 245         if (rc) {
 246                 remove_memory(nid, lmb->base_addr, block_sz);
 247                 dlpar_release_drc(lmb->drc_index);
 248                 return rc;
 249         }
 250
 251         lmb->flags |= DRCONF_MEM_ASSIGNED;
 252         return 0;
 253 }
 254
 255 static int dlpar_memory_add_by_count(u32 lmbs_to_add, struct property *prop)
 256 {
 257         struct of_drconf_cell *lmbs;
 258         u32 num_lmbs, *p;
 259         int lmbs_available = 0;
 260         int lmbs_added = 0;
 261         int i, rc;
 262
 263         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 264
 265         if (lmbs_to_add == 0)
 266                 return -EINVAL;
 267
 268         p = prop->value;
 269         num_lmbs = *p++;
 270         lmbs = (struct of_drconf_cell *)p;
 271
 272         /* Validate that there are enough LMBs to satisfy the request */
 273         for (i = 0; i < num_lmbs; i++) {
 274                 if (!(lmbs[i].flags & DRCONF_MEM_ASSIGNED))
 275                         lmbs_available++;
 276         }
 277
 278         if (lmbs_available < lmbs_to_add)
 279                 return -EINVAL;
 280
 281         for (i = 0; i < num_lmbs && lmbs_to_add != lmbs_added; i++) {
 282                 rc = dlpar_add_lmb(&lmbs[i]);
 283                 if (rc)
 284                         continue;
 285
 286                 lmbs_added++;
 287
 288                 /* Mark this lmb so we can remove it later if all of the
 289                  * requested LMBs cannot be added.
 290                  */
 291                 lmbs[i].reserved = 1;
 292         }
 293
 294         if (lmbs_added != lmbs_to_add) {
 295                 /* TODO: remove added lmbs */
 296                 rc = -EINVAL;
 297         } else {
 298                 for (i = 0; i < num_lmbs; i++) {
 299                         if (!lmbs[i].reserved)
 300                                 continue;
 301
 302                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 303                                 lmbs[i].base_addr, lmbs[i].drc_index);
 304                         lmbs[i].reserved = 0;
 305                 }
 306         }
 307
 308         return rc;
 309 }
 310
 311 static int dlpar_memory_add_by_index(u32 drc_index, struct property *prop)
 312 {
 313         struct of_drconf_cell *lmbs;
 314         u32 num_lmbs, *p;
 315         int i, lmb_found;
 316         int rc;
 317
 318         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 319
 320         p = prop->value;
 321         num_lmbs = *p++;
 322         lmbs = (struct of_drconf_cell *)p;
 323
 324         lmb_found = 0;
 325         for (i = 0; i < num_lmbs; i++) {
 326                 if (lmbs[i].drc_index == drc_index) {
 327                         lmb_found = 1;
 328                         rc = dlpar_add_lmb(&lmbs[i]);
 329                         break;
 330                 }
 331         }
 332
 333         if (!lmb_found)
 334                 rc = -EINVAL;
 335
 336         if (rc)
 337                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 338         else
 339                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 340                         lmbs[i].base_addr, drc_index);
 341
 342         return rc;
 343 }
 344
 345 static void dlpar_update_drconf_property(struct device_node *dn,
 346                                          struct property *prop)
 347 {
 348         struct of_drconf_cell *lmbs;
 349         u32 num_lmbs, *p;
 350         int i;
 351
 352         /* Convert the property back to BE */
 353         p = prop->value;
 354         num_lmbs = *p;
 355         *p = cpu_to_be32(*p);
 356         p++;
 357
 358         lmbs = (struct of_drconf_cell *)p;
 359         for (i = 0; i < num_lmbs; i++) {
 360                 lmbs[i].base_addr = cpu_to_be64(lmbs[i].base_addr);
 361                 lmbs[i].drc_index = cpu_to_be32(lmbs[i].drc_index);
 362                 lmbs[i].flags = cpu_to_be32(lmbs[i].flags);
 363         }
 364
 365         rtas_hp_event = true;
 366         of_update_property(dn, prop);
 367         rtas_hp_event = false;
 368 }
 369
 370 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 371 {
 372         struct device_node *dn;
 373         struct property *prop;
 374         u32 count, drc_index;
 375         int rc;
 376
 377         count = hp_elog->_drc_u.drc_count;
 378         drc_index = hp_elog->_drc_u.drc_index;
 379
 380         lock_device_hotplug();
 381
 382         dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 383         if (!dn)
 384                 return -EINVAL;
 385
 386         prop = dlpar_clone_drconf_property(dn);
 387         if (!prop) {
 388                 of_node_put(dn);
 389                 return -EINVAL;
 390         }
 391
 392         switch (hp_elog->action) {
 393         case PSERIES_HP_ELOG_ACTION_ADD:
 394                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT)
 395                         rc = dlpar_memory_add_by_count(count, prop);
 396                 else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX)
 397                         rc = dlpar_memory_add_by_index(drc_index, prop);
 398                 else
 399                         rc = -EINVAL;
 400                 break;
 401         default:
 402                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 403                 rc = -EINVAL;
 404                 break;
 405         }
 406
 407         if (rc)
 408                 dlpar_free_drconf_property(prop);
 409         else
 410                 dlpar_update_drconf_property(dn, prop);
 411
 412         of_node_put(dn);
 413         unlock_device_hotplug();
 414         return rc;
 415 }
 416
 417 static int pseries_add_mem_node(struct device_node *np)
 418 {
 419         const char *type;
 420         const __be32 *regs;
 421         unsigned long base;
 422         unsigned int lmb_size;
 423         int ret = -EINVAL;
 424
 425         /*
 426          * Check to see if we are actually adding memory
 427          */
 428         type = of_get_property(np, "device_type", NULL);
 429         if (type == NULL || strcmp(type, "memory") != 0)
 430                 return 0;
 431
 432         /*
 433          * Find the base and size of the memblock
 434          */
 435         regs = of_get_property(np, "reg", NULL);
 436         if (!regs)
 437                 return ret;
 438
 439         base = be64_to_cpu(*(unsigned long *)regs);
 440         lmb_size = be32_to_cpu(regs[3]);
 441
 442         /*
 443          * Update memory region to represent the memory add
 444          */
 445         ret = memblock_add(base, lmb_size);
 446         return (ret < 0) ? -EINVAL : 0;
 447 }
 448
 449 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
 450 {
 451         struct of_drconf_cell *new_drmem, *old_drmem;
 452         unsigned long memblock_size;
 453         u32 entries;
 454         __be32 *p;
 455         int i, rc = -EINVAL;
 456
 457         if (rtas_hp_event)
 458                 return 0;
 459
 460         memblock_size = pseries_memory_block_size();
 461         if (!memblock_size)
 462                 return -EINVAL;
 463
 464         p = (__be32 *) pr->old_prop->value;
 465         if (!p)
 466                 return -EINVAL;
 467
 468         /* The first int of the property is the number of lmb's described
 469          * by the property. This is followed by an array of of_drconf_cell
 470          * entries. Get the number of entries and skip to the array of
 471          * of_drconf_cell's.
 472          */
 473         entries = be32_to_cpu(*p++);
 474         old_drmem = (struct of_drconf_cell *)p;
 475
 476         p = (__be32 *)pr->prop->value;
 477         p++;
 478         new_drmem = (struct of_drconf_cell *)p;
 479
 480         for (i = 0; i < entries; i++) {
 481                 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
 482                     (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
 483                         rc = pseries_remove_memblock(
 484                                 be64_to_cpu(old_drmem[i].base_addr),
 485                                                      memblock_size);
 486                         break;
 487                 } else if ((!(be32_to_cpu(old_drmem[i].flags) &
 488                             DRCONF_MEM_ASSIGNED)) &&
 489                             (be32_to_cpu(new_drmem[i].flags) &
 490                             DRCONF_MEM_ASSIGNED)) {
 491                         rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
 492                                           memblock_size);
 493                         rc = (rc < 0) ? -EINVAL : 0;
 494                         break;
 495                 }
 496         }
 497         return rc;
 498 }
 499
 500 static int pseries_memory_notifier(struct notifier_block *nb,
 501                                    unsigned long action, void *data)
 502 {
 503         struct of_reconfig_data *rd = data;
 504         int err = 0;
 505
 506         switch (action) {
 507         case OF_RECONFIG_ATTACH_NODE:
 508                 err = pseries_add_mem_node(rd->dn);
 509                 break;
 510         case OF_RECONFIG_DETACH_NODE:
 511                 err = pseries_remove_mem_node(rd->dn);
 512                 break;
 513         case OF_RECONFIG_UPDATE_PROPERTY:
 514                 if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
 515                         err = pseries_update_drconf_memory(rd);
 516                 break;
 517         }
 518         return notifier_from_errno(err);
 519 }
 520
 521 static struct notifier_block pseries_mem_nb = {
 522         .notifier_call = pseries_memory_notifier,
 523 };
 524
 525 static int __init pseries_memory_hotplug_init(void)
 526 {
 527         if (firmware_has_feature(FW_FEATURE_LPAR))
 528                 of_reconfig_notifier_register(&pseries_mem_nb);
 529
 530         return 0;
 531 }
 532 machine_device_initcall(pseries, pseries_memory_hotplug_init);