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 #include <linux/acpi.h>
  14 #include <acpi/processor.h>
  15
  16 #include "internal.h"
  17
  18 #define PREFIX                  "ACPI: "
  19 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  20 ACPI_MODULE_NAME("processor_core");
  21
  22 static int map_lapic_id(struct acpi_subtable_header *entry,
  23                  u32 acpi_id, int *apic_id)
  24 {
  25         struct acpi_madt_local_apic *lapic =
  26                 (struct acpi_madt_local_apic *)entry;
  27
  28         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  29                 return -ENODEV;
  30
  31         if (lapic->processor_id != acpi_id)
  32                 return -EINVAL;
  33
  34         *apic_id = lapic->id;
  35         return 0;
  36 }
  37
  38 static int map_x2apic_id(struct acpi_subtable_header *entry,
  39                          int device_declaration, u32 acpi_id, int *apic_id)
  40 {
  41         struct acpi_madt_local_x2apic *apic =
  42                 (struct acpi_madt_local_x2apic *)entry;
  43
  44         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  45                 return -ENODEV;
  46
  47         if (device_declaration && (apic->uid == acpi_id)) {
  48                 *apic_id = apic->local_apic_id;
  49                 return 0;
  50         }
  51
  52         return -EINVAL;
  53 }
  54
  55 static int map_lsapic_id(struct acpi_subtable_header *entry,
  56                 int device_declaration, u32 acpi_id, int *apic_id)
  57 {
  58         struct acpi_madt_local_sapic *lsapic =
  59                 (struct acpi_madt_local_sapic *)entry;
  60
  61         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  62                 return -ENODEV;
  63
  64         if (device_declaration) {
  65                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  66                         return -EINVAL;
  67         } else if (lsapic->processor_id != acpi_id)
  68                 return -EINVAL;
  69
  70         *apic_id = (lsapic->id << 8) | lsapic->eid;
  71         return 0;
  72 }
  73
  74 static int map_gic_id(struct acpi_subtable_header *entry,
  75                 int device_declaration, u32 acpi_id, int *apic_id)
  76 {
  77         struct acpi_madt_generic_interrupt *gic =
  78                 (struct acpi_madt_generic_interrupt *)entry;
  79
  80         if (!(gic->flags & ACPI_MADT_ENABLED))
  81                 return -ENODEV;
  82
  83         /*
  84          * In the GIC interrupt model, logical processors are
  85          * required to have a Processor Device object in the DSDT,
  86          * so we should check device_declaration here
  87          */
  88         if (device_declaration && (gic->uid == acpi_id)) {
  89                 *apic_id = gic->gic_id;
  90                 return 0;
  91         }
  92
  93         return -EINVAL;
  94 }
  95
  96 static int map_madt_entry(int type, u32 acpi_id)
  97 {
  98         unsigned long madt_end, entry;
  99         static struct acpi_table_madt *madt;
 100         static int read_madt;
 101         int apic_id = -1;
 102
 103         if (!read_madt) {
 104                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 105                                         (struct acpi_table_header **)&madt)))
 106                         madt = NULL;
 107                 read_madt++;
 108         }
 109
 110         if (!madt)
 111                 return apic_id;
 112
 113         entry = (unsigned long)madt;
 114         madt_end = entry + madt->header.length;
 115
 116         /* Parse all entries looking for a match. */
 117
 118         entry += sizeof(struct acpi_table_madt);
 119         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 120                 struct acpi_subtable_header *header =
 121                         (struct acpi_subtable_header *)entry;
 122                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 123                         if (!map_lapic_id(header, acpi_id, &apic_id))
 124                                 break;
 125                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 126                         if (!map_x2apic_id(header, type, acpi_id, &apic_id))
 127                                 break;
 128                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 129                         if (!map_lsapic_id(header, type, acpi_id, &apic_id))
 130                                 break;
 131                 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 132                         if (!map_gic_id(header, type, acpi_id, &apic_id))
 133                                 break;
 134                 }
 135                 entry += header->length;
 136         }
 137         return apic_id;
 138 }
 139
 140 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 141 {
 142         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 143         union acpi_object *obj;
 144         struct acpi_subtable_header *header;
 145         int apic_id = -1;
 146
 147         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 148                 goto exit;
 149
 150         if (!buffer.length || !buffer.pointer)
 151                 goto exit;
 152
 153         obj = buffer.pointer;
 154         if (obj->type != ACPI_TYPE_BUFFER ||
 155             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 156                 goto exit;
 157         }
 158
 159         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 160         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 161                 map_lapic_id(header, acpi_id, &apic_id);
 162         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 163                 map_lsapic_id(header, type, acpi_id, &apic_id);
 164         } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 165                 map_gic_id(header, type, acpi_id, &apic_id);
 166         }
 167
 168 exit:
 169         kfree(buffer.pointer);
 170         return apic_id;
 171 }
 172
 173 int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
 174 {
 175         int apic_id;
 176
 177         apic_id = map_mat_entry(handle, type, acpi_id);
 178         if (apic_id == -1)
 179                 apic_id = map_madt_entry(type, acpi_id);
 180
 181         return apic_id;
 182 }
 183
 184 int acpi_map_cpuid(int apic_id, u32 acpi_id)
 185 {
 186 #ifdef CONFIG_SMP
 187         int i;
 188 #endif
 189
 190         if (apic_id == -1) {
 191                 /*
 192                  * On UP processor, there is no _MAT or MADT table.
 193                  * So above apic_id is always set to -1.
 194                  *
 195                  * BIOS may define multiple CPU handles even for UP processor.
 196                  * For example,
 197                  *
 198                  * Scope (_PR)
 199                  * {
 200                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 201                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 202                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 203                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 204                  * }
 205                  *
 206                  * Ignores apic_id and always returns 0 for the processor
 207                  * handle with acpi id 0 if nr_cpu_ids is 1.
 208                  * This should be the case if SMP tables are not found.
 209                  * Return -1 for other CPU's handle.
 210                  */
 211                 if (nr_cpu_ids <= 1 && acpi_id == 0)
 212                         return acpi_id;
 213                 else
 214                         return apic_id;
 215         }
 216
 217 #ifdef CONFIG_SMP
 218         for_each_possible_cpu(i) {
 219                 if (cpu_physical_id(i) == apic_id)
 220                         return i;
 221         }
 222 #else
 223         /* In UP kernel, only processor 0 is valid */
 224         if (apic_id == 0)
 225                 return apic_id;
 226 #endif
 227         return -1;
 228 }
 229
 230 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 231 {
 232         int apic_id;
 233
 234         apic_id = acpi_get_apicid(handle, type, acpi_id);
 235
 236         return acpi_map_cpuid(apic_id, acpi_id);
 237 }
 238 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 239
 240 static bool __init processor_physically_present(acpi_handle handle)
 241 {
 242         int cpuid, type;
 243         u32 acpi_id;
 244         acpi_status status;
 245         acpi_object_type acpi_type;
 246         unsigned long long tmp;
 247         union acpi_object object = { 0 };
 248         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 249
 250         status = acpi_get_type(handle, &acpi_type);
 251         if (ACPI_FAILURE(status))
 252                 return false;
 253
 254         switch (acpi_type) {
 255         case ACPI_TYPE_PROCESSOR:
 256                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 257                 if (ACPI_FAILURE(status))
 258                         return false;
 259                 acpi_id = object.processor.proc_id;
 260                 break;
 261         case ACPI_TYPE_DEVICE:
 262                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 263                 if (ACPI_FAILURE(status))
 264                         return false;
 265                 acpi_id = tmp;
 266                 break;
 267         default:
 268                 return false;
 269         }
 270
 271         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 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 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 *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 acpi_status
 336 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 337 {
 338         acpi_status status = AE_OK;
 339
 340         if (boot_option_idle_override == IDLE_NOMWAIT) {
 341                 /*
 342                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 343                  * mode will be disabled in the parameter of _PDC object.
 344                  * Of course C1_FFH access mode will also be disabled.
 345                  */
 346                 union acpi_object *obj;
 347                 u32 *buffer = NULL;
 348
 349                 obj = pdc_in->pointer;
 350                 buffer = (u32 *)(obj->buffer.pointer);
 351                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 352
 353         }
 354         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 355
 356         if (ACPI_FAILURE(status))
 357                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 358                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 359
 360         return status;
 361 }
 362
 363 void acpi_processor_set_pdc(acpi_handle handle)
 364 {
 365         struct acpi_object_list *obj_list;
 366
 367         if (arch_has_acpi_pdc() == false)
 368                 return;
 369
 370         obj_list = acpi_processor_alloc_pdc();
 371         if (!obj_list)
 372                 return;
 373
 374         acpi_processor_eval_pdc(handle, obj_list);
 375
 376         kfree(obj_list->pointer->buffer.pointer);
 377         kfree(obj_list->pointer);
 378         kfree(obj_list);
 379 }
 380
 381 static acpi_status __init
 382 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 383 {
 384         if (processor_physically_present(handle) == false)
 385                 return AE_OK;
 386
 387         acpi_processor_set_pdc(handle);
 388         return AE_OK;
 389 }
 390
 391 #if defined(CONFIG_X86) || defined(CONFIG_IA64)
 392 static int __init set_no_mwait(const struct dmi_system_id *id)
 393 {
 394         pr_notice(PREFIX "%s detected - disabling mwait for CPU C-states\n",
 395                   id->ident);
 396         boot_option_idle_override = IDLE_NOMWAIT;
 397         return 0;
 398 }
 399
 400 static struct dmi_system_id processor_idle_dmi_table[] __initdata = {
 401         {
 402         set_no_mwait, "Extensa 5220", {
 403         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
 404         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 405         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
 406         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
 407         {},
 408 };
 409
 410 static void __init processor_dmi_check(void)
 411 {
 412         /*
 413          * Check whether the system is DMI table. If yes, OSPM
 414          * should not use mwait for CPU-states.
 415          */
 416         dmi_check_system(processor_idle_dmi_table);
 417 }
 418 #else
 419 static inline void processor_dmi_check(void) {}
 420 #endif
 421
 422 void __init acpi_early_processor_set_pdc(void)
 423 {
 424         processor_dmi_check();
 425
 426         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 427                             ACPI_UINT32_MAX,
 428                             early_init_pdc, NULL, NULL, NULL);
 429         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL);
 430 }