1 /* 2 * Support for dynamic reconfiguration for PCI, Memory, and CPU 3 * Hotplug and Dynamic Logical Partitioning on RPA platforms. 4 * 5 * Copyright (C) 2009 Nathan Fontenot 6 * Copyright (C) 2009 IBM Corporation 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License version 10 * 2 as published by the Free Software Foundation. 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/notifier.h> 15 #include <linux/spinlock.h> 16 #include <linux/cpu.h> 17 #include <linux/slab.h> 18 #include <linux/of.h> 19 #include "offline_states.h" 20 21 #include <asm/prom.h> 22 #include <asm/machdep.h> 23 #include <asm/uaccess.h> 24 #include <asm/rtas.h> 25 26 struct cc_workarea { 27 u32 drc_index; 28 u32 zero; 29 u32 name_offset; 30 u32 prop_length; 31 u32 prop_offset; 32 }; 33 34 void dlpar_free_cc_property(struct property *prop) 35 { 36 kfree(prop->name); 37 kfree(prop->value); 38 kfree(prop); 39 } 40 41 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa) 42 { 43 struct property *prop; 44 char *name; 45 char *value; 46 47 prop = kzalloc(sizeof(*prop), GFP_KERNEL); 48 if (!prop) 49 return NULL; 50 51 name = (char *)ccwa + ccwa->name_offset; 52 prop->name = kstrdup(name, GFP_KERNEL); 53 54 prop->length = ccwa->prop_length; 55 value = (char *)ccwa + ccwa->prop_offset; 56 prop->value = kmemdup(value, prop->length, GFP_KERNEL); 57 if (!prop->value) { 58 dlpar_free_cc_property(prop); 59 return NULL; 60 } 61 62 return prop; 63 } 64 65 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa, 66 const char *path) 67 { 68 struct device_node *dn; 69 char *name; 70 71 /* If parent node path is "/" advance path to NULL terminator to 72 * prevent double leading slashs in full_name. 73 */ 74 if (!path[1]) 75 path++; 76 77 dn = kzalloc(sizeof(*dn), GFP_KERNEL); 78 if (!dn) 79 return NULL; 80 81 name = (char *)ccwa + ccwa->name_offset; 82 dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name); 83 if (!dn->full_name) { 84 kfree(dn); 85 return NULL; 86 } 87 88 of_node_set_flag(dn, OF_DYNAMIC); 89 90 return dn; 91 } 92 93 static void dlpar_free_one_cc_node(struct device_node *dn) 94 { 95 struct property *prop; 96 97 while (dn->properties) { 98 prop = dn->properties; 99 dn->properties = prop->next; 100 dlpar_free_cc_property(prop); 101 } 102 103 kfree(dn->full_name); 104 kfree(dn); 105 } 106 107 void dlpar_free_cc_nodes(struct device_node *dn) 108 { 109 if (dn->child) 110 dlpar_free_cc_nodes(dn->child); 111 112 if (dn->sibling) 113 dlpar_free_cc_nodes(dn->sibling); 114 115 dlpar_free_one_cc_node(dn); 116 } 117 118 #define COMPLETE 0 119 #define NEXT_SIBLING 1 120 #define NEXT_CHILD 2 121 #define NEXT_PROPERTY 3 122 #define PREV_PARENT 4 123 #define MORE_MEMORY 5 124 #define CALL_AGAIN -2 125 #define ERR_CFG_USE -9003 126 127 struct device_node *dlpar_configure_connector(u32 drc_index, 128 struct device_node *parent) 129 { 130 struct device_node *dn; 131 struct device_node *first_dn = NULL; 132 struct device_node *last_dn = NULL; 133 struct property *property; 134 struct property *last_property = NULL; 135 struct cc_workarea *ccwa; 136 char *data_buf; 137 const char *parent_path = parent->full_name; 138 int cc_token; 139 int rc = -1; 140 141 cc_token = rtas_token("ibm,configure-connector"); 142 if (cc_token == RTAS_UNKNOWN_SERVICE) 143 return NULL; 144 145 data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL); 146 if (!data_buf) 147 return NULL; 148 149 ccwa = (struct cc_workarea *)&data_buf[0]; 150 ccwa->drc_index = drc_index; 151 ccwa->zero = 0; 152 153 do { 154 /* Since we release the rtas_data_buf lock between configure 155 * connector calls we want to re-populate the rtas_data_buffer 156 * with the contents of the previous call. 157 */ 158 spin_lock(&rtas_data_buf_lock); 159 160 memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE); 161 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL); 162 memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE); 163 164 spin_unlock(&rtas_data_buf_lock); 165 166 switch (rc) { 167 case COMPLETE: 168 break; 169 170 case NEXT_SIBLING: 171 dn = dlpar_parse_cc_node(ccwa, parent_path); 172 if (!dn) 173 goto cc_error; 174 175 dn->parent = last_dn->parent; 176 last_dn->sibling = dn; 177 last_dn = dn; 178 break; 179 180 case NEXT_CHILD: 181 if (first_dn) 182 parent_path = last_dn->full_name; 183 184 dn = dlpar_parse_cc_node(ccwa, parent_path); 185 if (!dn) 186 goto cc_error; 187 188 if (!first_dn) { 189 dn->parent = parent; 190 first_dn = dn; 191 } else { 192 dn->parent = last_dn; 193 if (last_dn) 194 last_dn->child = dn; 195 } 196 197 last_dn = dn; 198 break; 199 200 case NEXT_PROPERTY: 201 property = dlpar_parse_cc_property(ccwa); 202 if (!property) 203 goto cc_error; 204 205 if (!last_dn->properties) 206 last_dn->properties = property; 207 else 208 last_property->next = property; 209 210 last_property = property; 211 break; 212 213 case PREV_PARENT: 214 last_dn = last_dn->parent; 215 parent_path = last_dn->parent->full_name; 216 break; 217 218 case CALL_AGAIN: 219 break; 220 221 case MORE_MEMORY: 222 case ERR_CFG_USE: 223 default: 224 printk(KERN_ERR "Unexpected Error (%d) " 225 "returned from configure-connector\n", rc); 226 goto cc_error; 227 } 228 } while (rc); 229 230 cc_error: 231 kfree(data_buf); 232 233 if (rc) { 234 if (first_dn) 235 dlpar_free_cc_nodes(first_dn); 236 237 return NULL; 238 } 239 240 return first_dn; 241 } 242 243 static struct device_node *derive_parent(const char *path) 244 { 245 struct device_node *parent; 246 char *last_slash; 247 248 last_slash = strrchr(path, '/'); 249 if (last_slash == path) { 250 parent = of_find_node_by_path("/"); 251 } else { 252 char *parent_path; 253 int parent_path_len = last_slash - path + 1; 254 parent_path = kmalloc(parent_path_len, GFP_KERNEL); 255 if (!parent_path) 256 return NULL; 257 258 strlcpy(parent_path, path, parent_path_len); 259 parent = of_find_node_by_path(parent_path); 260 kfree(parent_path); 261 } 262 263 return parent; 264 } 265 266 int dlpar_attach_node(struct device_node *dn) 267 { 268 int rc; 269 270 dn->parent = derive_parent(dn->full_name); 271 if (!dn->parent) 272 return -ENOMEM; 273 274 rc = of_attach_node(dn); 275 if (rc) { 276 printk(KERN_ERR "Failed to add device node %s\n", 277 dn->full_name); 278 return rc; 279 } 280 281 of_node_put(dn->parent); 282 return 0; 283 } 284 285 int dlpar_detach_node(struct device_node *dn) 286 { 287 struct device_node *child; 288 int rc; 289 290 child = of_get_next_child(dn, NULL); 291 while (child) { 292 dlpar_detach_node(child); 293 child = of_get_next_child(dn, child); 294 } 295 296 rc = of_detach_node(dn); 297 if (rc) 298 return rc; 299 300 of_node_put(dn); /* Must decrement the refcount */ 301 return 0; 302 } 303 304 #define DR_ENTITY_SENSE 9003 305 #define DR_ENTITY_PRESENT 1 306 #define DR_ENTITY_UNUSABLE 2 307 #define ALLOCATION_STATE 9003 308 #define ALLOC_UNUSABLE 0 309 #define ALLOC_USABLE 1 310 #define ISOLATION_STATE 9001 311 #define ISOLATE 0 312 #define UNISOLATE 1 313 314 int dlpar_acquire_drc(u32 drc_index) 315 { 316 int dr_status, rc; 317 318 rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status, 319 DR_ENTITY_SENSE, drc_index); 320 if (rc || dr_status != DR_ENTITY_UNUSABLE) 321 return -1; 322 323 rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE); 324 if (rc) 325 return rc; 326 327 rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE); 328 if (rc) { 329 rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE); 330 return rc; 331 } 332 333 return 0; 334 } 335 336 int dlpar_release_drc(u32 drc_index) 337 { 338 int dr_status, rc; 339 340 rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status, 341 DR_ENTITY_SENSE, drc_index); 342 if (rc || dr_status != DR_ENTITY_PRESENT) 343 return -1; 344 345 rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE); 346 if (rc) 347 return rc; 348 349 rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE); 350 if (rc) { 351 rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE); 352 return rc; 353 } 354 355 return 0; 356 } 357 358 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE 359 360 static int dlpar_online_cpu(struct device_node *dn) 361 { 362 int rc = 0; 363 unsigned int cpu; 364 int len, nthreads, i; 365 const u32 *intserv; 366 367 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len); 368 if (!intserv) 369 return -EINVAL; 370 371 nthreads = len / sizeof(u32); 372 373 cpu_maps_update_begin(); 374 for (i = 0; i < nthreads; i++) { 375 for_each_present_cpu(cpu) { 376 if (get_hard_smp_processor_id(cpu) != intserv[i]) 377 continue; 378 BUG_ON(get_cpu_current_state(cpu) 379 != CPU_STATE_OFFLINE); 380 cpu_maps_update_done(); 381 rc = cpu_up(cpu); 382 if (rc) 383 goto out; 384 cpu_maps_update_begin(); 385 386 break; 387 } 388 if (cpu == num_possible_cpus()) 389 printk(KERN_WARNING "Could not find cpu to online " 390 "with physical id 0x%x\n", intserv[i]); 391 } 392 cpu_maps_update_done(); 393 394 out: 395 return rc; 396 397 } 398 399 static ssize_t dlpar_cpu_probe(const char *buf, size_t count) 400 { 401 struct device_node *dn, *parent; 402 unsigned long drc_index; 403 int rc; 404 405 rc = strict_strtoul(buf, 0, &drc_index); 406 if (rc) 407 return -EINVAL; 408 409 parent = of_find_node_by_path("/cpus"); 410 if (!parent) 411 return -ENODEV; 412 413 dn = dlpar_configure_connector(drc_index, parent); 414 if (!dn) 415 return -EINVAL; 416 417 of_node_put(parent); 418 419 rc = dlpar_acquire_drc(drc_index); 420 if (rc) { 421 dlpar_free_cc_nodes(dn); 422 return -EINVAL; 423 } 424 425 rc = dlpar_attach_node(dn); 426 if (rc) { 427 dlpar_release_drc(drc_index); 428 dlpar_free_cc_nodes(dn); 429 return rc; 430 } 431 432 rc = dlpar_online_cpu(dn); 433 if (rc) 434 return rc; 435 436 return count; 437 } 438 439 static int dlpar_offline_cpu(struct device_node *dn) 440 { 441 int rc = 0; 442 unsigned int cpu; 443 int len, nthreads, i; 444 const u32 *intserv; 445 446 intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len); 447 if (!intserv) 448 return -EINVAL; 449 450 nthreads = len / sizeof(u32); 451 452 cpu_maps_update_begin(); 453 for (i = 0; i < nthreads; i++) { 454 for_each_present_cpu(cpu) { 455 if (get_hard_smp_processor_id(cpu) != intserv[i]) 456 continue; 457 458 if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE) 459 break; 460 461 if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) { 462 set_preferred_offline_state(cpu, CPU_STATE_OFFLINE); 463 cpu_maps_update_done(); 464 rc = cpu_down(cpu); 465 if (rc) 466 goto out; 467 cpu_maps_update_begin(); 468 break; 469 470 } 471 472 /* 473 * The cpu is in CPU_STATE_INACTIVE. 474 * Upgrade it's state to CPU_STATE_OFFLINE. 475 */ 476 set_preferred_offline_state(cpu, CPU_STATE_OFFLINE); 477 BUG_ON(plpar_hcall_norets(H_PROD, intserv[i]) 478 != H_SUCCESS); 479 __cpu_die(cpu); 480 break; 481 } 482 if (cpu == num_possible_cpus()) 483 printk(KERN_WARNING "Could not find cpu to offline " 484 "with physical id 0x%x\n", intserv[i]); 485 } 486 cpu_maps_update_done(); 487 488 out: 489 return rc; 490 491 } 492 493 static ssize_t dlpar_cpu_release(const char *buf, size_t count) 494 { 495 struct device_node *dn; 496 const u32 *drc_index; 497 int rc; 498 499 dn = of_find_node_by_path(buf); 500 if (!dn) 501 return -EINVAL; 502 503 drc_index = of_get_property(dn, "ibm,my-drc-index", NULL); 504 if (!drc_index) { 505 of_node_put(dn); 506 return -EINVAL; 507 } 508 509 rc = dlpar_offline_cpu(dn); 510 if (rc) { 511 of_node_put(dn); 512 return -EINVAL; 513 } 514 515 rc = dlpar_release_drc(*drc_index); 516 if (rc) { 517 of_node_put(dn); 518 return rc; 519 } 520 521 rc = dlpar_detach_node(dn); 522 if (rc) { 523 dlpar_acquire_drc(*drc_index); 524 return rc; 525 } 526 527 of_node_put(dn); 528 529 return count; 530 } 531 532 static int __init pseries_dlpar_init(void) 533 { 534 ppc_md.cpu_probe = dlpar_cpu_probe; 535 ppc_md.cpu_release = dlpar_cpu_release; 536 537 return 0; 538 } 539 machine_device_initcall(pseries, pseries_dlpar_init); 540 541 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ 542