drivers/acpi/processor_core.c

   1 /*
   2  * Copyright (C) 2005 Intel Corporation
   3  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
   4  *
   5  *      Alex Chiang <achiang@hp.com>
   6  *      - Unified x86/ia64 implementations
   7  *      Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
   8  *      - Added _PDC for platforms with Intel CPUs
   9  */
  10 #include <linux/export.h>
  11 #include <linux/dmi.h>
  12 #include <linux/slab.h>
  13
  14 #include <acpi/acpi_drivers.h>
  15 #include <acpi/processor.h>
  16
  17 #include "internal.h"
  18
  19 #define PREFIX                  "ACPI: "
  20 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  21 ACPI_MODULE_NAME("processor_core");
  22
  23 #ifdef CONFIG_PROCESSOR_EXTERNAL_CONTROL
  24 /*
  25  * External processor control logic may register with its own set of
  26  * ops to get ACPI related notification. One example is like VMM.
  27  */
  28 const struct processor_extcntl_ops *processor_extcntl_ops;
  29 EXPORT_SYMBOL(processor_extcntl_ops);
  30 #endif
  31
  32 static int __init set_no_mwait(const struct dmi_system_id *id)
  33 {
  34         printk(KERN_NOTICE PREFIX "%s detected - "
  35                 "disabling mwait for CPU C-states\n", id->ident);
  36         boot_option_idle_override = IDLE_NOMWAIT;
  37         return 0;
  38 }
  39
  40 static struct dmi_system_id __initdata processor_idle_dmi_table[] = {
  41         {
  42         set_no_mwait, "Extensa 5220", {
  43         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
  44         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
  45         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
  46         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
  47         {},
  48 };
  49
  50 static int map_lapic_id(struct acpi_subtable_header *entry,
  51                  u32 acpi_id, int *apic_id)
  52 {
  53         struct acpi_madt_local_apic *lapic =
  54                 (struct acpi_madt_local_apic *)entry;
  55
  56         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  57                 return 0;
  58
  59         if (lapic->processor_id != acpi_id)
  60                 return 0;
  61
  62         *apic_id = lapic->id;
  63         return 1;
  64 }
  65
  66 static int map_x2apic_id(struct acpi_subtable_header *entry,
  67                          int device_declaration, u32 acpi_id, int *apic_id)
  68 {
  69         struct acpi_madt_local_x2apic *apic =
  70                 (struct acpi_madt_local_x2apic *)entry;
  71
  72         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  73                 return 0;
  74
  75         if (device_declaration && (apic->uid == acpi_id)) {
  76                 *apic_id = apic->local_apic_id;
  77                 return 1;
  78         }
  79
  80         return 0;
  81 }
  82
  83 static int map_lsapic_id(struct acpi_subtable_header *entry,
  84                 int device_declaration, u32 acpi_id, int *apic_id)
  85 {
  86         struct acpi_madt_local_sapic *lsapic =
  87                 (struct acpi_madt_local_sapic *)entry;
  88
  89         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  90                 return 0;
  91
  92         if (device_declaration) {
  93                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  94                         return 0;
  95         } else if (lsapic->processor_id != acpi_id)
  96                 return 0;
  97
  98         *apic_id = (lsapic->id << 8) | lsapic->eid;
  99         return 1;
 100 }
 101
 102 static int map_madt_entry(int type, u32 acpi_id)
 103 {
 104         unsigned long madt_end, entry;
 105         static struct acpi_table_madt *madt;
 106         static int read_madt;
 107         int apic_id = -1;
 108
 109         if (!read_madt) {
 110                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 111                                         (struct acpi_table_header **)&madt)))
 112                         madt = NULL;
 113                 read_madt++;
 114         }
 115
 116         if (!madt)
 117                 return apic_id;
 118
 119         entry = (unsigned long)madt;
 120         madt_end = entry + madt->header.length;
 121
 122         /* Parse all entries looking for a match. */
 123
 124         entry += sizeof(struct acpi_table_madt);
 125         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 126                 struct acpi_subtable_header *header =
 127                         (struct acpi_subtable_header *)entry;
 128                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 129                         if (map_lapic_id(header, acpi_id, &apic_id))
 130                                 break;
 131                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 132                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
 133                                 break;
 134                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 135                         if (map_lsapic_id(header, type, acpi_id, &apic_id))
 136                                 break;
 137                 }
 138                 entry += header->length;
 139         }
 140         return apic_id;
 141 }
 142
 143 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 144 {
 145         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 146         union acpi_object *obj;
 147         struct acpi_subtable_header *header;
 148         int apic_id = -1;
 149
 150         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 151                 goto exit;
 152
 153         if (!buffer.length || !buffer.pointer)
 154                 goto exit;
 155
 156         obj = buffer.pointer;
 157         if (obj->type != ACPI_TYPE_BUFFER ||
 158             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 159                 goto exit;
 160         }
 161
 162         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 163         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 164                 map_lapic_id(header, acpi_id, &apic_id);
 165         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 166                 map_lsapic_id(header, type, acpi_id, &apic_id);
 167         }
 168
 169 exit:
 170         if (buffer.pointer)
 171                 kfree(buffer.pointer);
 172         return apic_id;
 173 }
 174
 175 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 176 {
 177         int i = 0, apic_id = -1;
 178
 179         if (type < 0) {
 180                 if (!processor_cntl_external())
 181                         return -1;
 182                 type = ~type;
 183                 i = 1;
 184         }
 185
 186         apic_id = map_mat_entry(handle, type, acpi_id);
 187         if (apic_id == -1)
 188                 apic_id = map_madt_entry(type, acpi_id);
 189         if (apic_id == -1 || i) {
 190                 /*
 191                  * On UP processor, there is no _MAT or MADT table.
 192                  * So above apic_id is always set to -1.
 193                  *
 194                  * BIOS may define multiple CPU handles even for UP processor.
 195                  * For example,
 196                  *
 197                  * Scope (_PR)
 198                  * {
 199                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 200                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 201                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 202                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 203                  * }
 204                  *
 205                  * Ignores apic_id and always return 0 for CPU0's handle.
 206                  * Return -1 for other CPU's handle.
 207                  */
 208                 if (acpi_id == 0 && !i)
 209                         return acpi_id;
 210                 else
 211                         return apic_id;
 212         }
 213
 214 #ifdef CONFIG_SMP
 215 #ifndef CONFIG_PROCESSOR_EXTERNAL_CONTROL
 216         for_each_possible_cpu(i) {
 217                 if (cpu_physical_id(i) == apic_id)
 218                         return i;
 219         }
 220 #else
 221         /*
 222          * Use of cpu_physical_id() is bogus here. Rather than defining a
 223          * stub enforcing a 1:1 mapping, we keep it undefined to catch bad
 224          * uses. Return as if there was a 1:1 mapping.
 225          */
 226         if (apic_id < nr_cpu_ids && cpu_possible(apic_id))
 227                 return apic_id;
 228 #endif
 229 #else
 230         /* In UP kernel, only processor 0 is valid */
 231         if (apic_id == 0)
 232                 return apic_id;
 233 #endif
 234         return -1;
 235 }
 236 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 237
 238 static bool __init processor_physically_present(acpi_handle handle)
 239 {
 240         int cpuid, type;
 241         u32 acpi_id;
 242         acpi_status status;
 243         acpi_object_type acpi_type;
 244         unsigned long long tmp;
 245         union acpi_object object = { 0 };
 246         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 247
 248         status = acpi_get_type(handle, &acpi_type);
 249         if (ACPI_FAILURE(status))
 250                 return false;
 251
 252         switch (acpi_type) {
 253         case ACPI_TYPE_PROCESSOR:
 254                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 255                 if (ACPI_FAILURE(status))
 256                         return false;
 257                 acpi_id = object.processor.proc_id;
 258                 break;
 259         case ACPI_TYPE_DEVICE:
 260                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 261                 if (ACPI_FAILURE(status))
 262                         return false;
 263                 acpi_id = tmp;
 264                 break;
 265         default:
 266                 return false;
 267         }
 268
 269         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 270         if (processor_cntl_external())
 271                 type = ~type;
 272         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 273
 274         if (cpuid == -1)
 275                 return false;
 276
 277         return true;
 278 }
 279
 280 static void __cpuinit acpi_set_pdc_bits(u32 *buf)
 281 {
 282         buf[0] = ACPI_PDC_REVISION_ID;
 283         buf[1] = 1;
 284
 285         /* Enable coordination with firmware's _TSD info */
 286         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 287
 288         /* Twiddle arch-specific bits needed for _PDC */
 289         arch_acpi_set_pdc_bits(buf);
 290 }
 291
 292 static struct acpi_object_list *__cpuinit acpi_processor_alloc_pdc(void)
 293 {
 294         struct acpi_object_list *obj_list;
 295         union acpi_object *obj;
 296         u32 *buf;
 297
 298         /* allocate and initialize pdc. It will be used later. */
 299         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 300         if (!obj_list) {
 301                 printk(KERN_ERR "Memory allocation error\n");
 302                 return NULL;
 303         }
 304
 305         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 306         if (!obj) {
 307                 printk(KERN_ERR "Memory allocation error\n");
 308                 kfree(obj_list);
 309                 return NULL;
 310         }
 311
 312         buf = kmalloc(12, GFP_KERNEL);
 313         if (!buf) {
 314                 printk(KERN_ERR "Memory allocation error\n");
 315                 kfree(obj);
 316                 kfree(obj_list);
 317                 return NULL;
 318         }
 319
 320         acpi_set_pdc_bits(buf);
 321
 322         obj->type = ACPI_TYPE_BUFFER;
 323         obj->buffer.length = 12;
 324         obj->buffer.pointer = (u8 *) buf;
 325         obj_list->count = 1;
 326         obj_list->pointer = obj;
 327
 328         return obj_list;
 329 }
 330
 331 /*
 332  * _PDC is required for a BIOS-OS handshake for most of the newer
 333  * ACPI processor features.
 334  */
 335 static int __cpuinit
 336 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 337 {
 338         acpi_status status = AE_OK;
 339
 340 #ifndef CONFIG_XEN
 341         if (boot_option_idle_override == IDLE_NOMWAIT) {
 342                 /*
 343                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 344                  * mode will be disabled in the parameter of _PDC object.
 345                  * Of course C1_FFH access mode will also be disabled.
 346                  */
 347 #else
 348         {
 349                 struct xen_platform_op op;
 350 #endif
 351                 union acpi_object *obj;
 352                 u32 *buffer = NULL;
 353
 354                 obj = pdc_in->pointer;
 355                 buffer = (u32 *)(obj->buffer.pointer);
 356 #ifndef CONFIG_XEN
 357                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 358 #else
 359                 op.cmd = XENPF_set_processor_pminfo;
 360                 op.u.set_pminfo.id = -1;
 361                 op.u.set_pminfo.type = XEN_PM_PDC;
 362                 set_xen_guest_handle(op.u.set_pminfo.u.pdc, buffer);
 363                 VOID(HYPERVISOR_platform_op(&op));
 364 #endif
 365         }
 366         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 367
 368         if (ACPI_FAILURE(status))
 369                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 370                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 371
 372         return status;
 373 }
 374
 375 void __cpuinit acpi_processor_set_pdc(acpi_handle handle)
 376 {
 377         struct acpi_object_list *obj_list;
 378
 379         if (arch_has_acpi_pdc() == false)
 380                 return;
 381
 382         obj_list = acpi_processor_alloc_pdc();
 383         if (!obj_list)
 384                 return;
 385
 386         acpi_processor_eval_pdc(handle, obj_list);
 387
 388         kfree(obj_list->pointer->buffer.pointer);
 389         kfree(obj_list->pointer);
 390         kfree(obj_list);
 391 }
 392
 393 static acpi_status __init
 394 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 395 {
 396         if (processor_physically_present(handle) == false)
 397                 return AE_OK;
 398
 399         acpi_processor_set_pdc(handle);
 400         return AE_OK;
 401 }
 402
 403 void __init acpi_early_processor_set_pdc(void)
 404 {
 405         /*
 406          * Check whether the system is DMI table. If yes, OSPM
 407          * should not use mwait for CPU-states.
 408          */
 409         dmi_check_system(processor_idle_dmi_table);
 410
 411         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 412                             ACPI_UINT32_MAX,
 413                             early_init_pdc, NULL, NULL, NULL);
 414         acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);
 415 }