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 _COMPONENT              ACPI_PROCESSOR_COMPONENT
  19 ACPI_MODULE_NAME("processor_core");
  20
  21 static int map_lapic_id(struct acpi_subtable_header *entry,
  22                  u32 acpi_id, int *apic_id)
  23 {
  24         struct acpi_madt_local_apic *lapic =
  25                 (struct acpi_madt_local_apic *)entry;
  26
  27         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  28                 return -ENODEV;
  29
  30         if (lapic->processor_id != acpi_id)
  31                 return -EINVAL;
  32
  33         *apic_id = lapic->id;
  34         return 0;
  35 }
  36
  37 static int map_x2apic_id(struct acpi_subtable_header *entry,
  38                          int device_declaration, u32 acpi_id, int *apic_id)
  39 {
  40         struct acpi_madt_local_x2apic *apic =
  41                 (struct acpi_madt_local_x2apic *)entry;
  42
  43         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  44                 return -ENODEV;
  45
  46         if (device_declaration && (apic->uid == acpi_id)) {
  47                 *apic_id = apic->local_apic_id;
  48                 return 0;
  49         }
  50
  51         return -EINVAL;
  52 }
  53
  54 static int map_lsapic_id(struct acpi_subtable_header *entry,
  55                 int device_declaration, u32 acpi_id, int *apic_id)
  56 {
  57         struct acpi_madt_local_sapic *lsapic =
  58                 (struct acpi_madt_local_sapic *)entry;
  59
  60         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  61                 return -ENODEV;
  62
  63         if (device_declaration) {
  64                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  65                         return -EINVAL;
  66         } else if (lsapic->processor_id != acpi_id)
  67                 return -EINVAL;
  68
  69         *apic_id = (lsapic->id << 8) | lsapic->eid;
  70         return 0;
  71 }
  72
  73 static int map_gic_id(struct acpi_subtable_header *entry,
  74                 int device_declaration, u32 acpi_id, int *apic_id)
  75 {
  76         struct acpi_madt_generic_interrupt *gic =
  77                 (struct acpi_madt_generic_interrupt *)entry;
  78
  79         if (!(gic->flags & ACPI_MADT_ENABLED))
  80                 return -ENODEV;
  81
  82         /*
  83          * In the GIC interrupt model, logical processors are
  84          * required to have a Processor Device object in the DSDT,
  85          * so we should check device_declaration here
  86          */
  87         if (device_declaration && (gic->uid == acpi_id)) {
  88                 *apic_id = gic->gic_id;
  89                 return 0;
  90         }
  91
  92         return -EINVAL;
  93 }
  94
  95 static int map_madt_entry(int type, u32 acpi_id)
  96 {
  97         unsigned long madt_end, entry;
  98         static struct acpi_table_madt *madt;
  99         static int read_madt;
 100         int apic_id = -1;
 101
 102         if (!read_madt) {
 103                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 104                                         (struct acpi_table_header **)&madt)))
 105                         madt = NULL;
 106                 read_madt++;
 107         }
 108
 109         if (!madt)
 110                 return apic_id;
 111
 112         entry = (unsigned long)madt;
 113         madt_end = entry + madt->header.length;
 114
 115         /* Parse all entries looking for a match. */
 116
 117         entry += sizeof(struct acpi_table_madt);
 118         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 119                 struct acpi_subtable_header *header =
 120                         (struct acpi_subtable_header *)entry;
 121                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 122                         if (!map_lapic_id(header, acpi_id, &apic_id))
 123                                 break;
 124                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 125                         if (!map_x2apic_id(header, type, acpi_id, &apic_id))
 126                                 break;
 127                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 128                         if (!map_lsapic_id(header, type, acpi_id, &apic_id))
 129                                 break;
 130                 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 131                         if (!map_gic_id(header, type, acpi_id, &apic_id))
 132                                 break;
 133                 }
 134                 entry += header->length;
 135         }
 136         return apic_id;
 137 }
 138
 139 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 140 {
 141         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 142         union acpi_object *obj;
 143         struct acpi_subtable_header *header;
 144         int apic_id = -1;
 145
 146         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 147                 goto exit;
 148
 149         if (!buffer.length || !buffer.pointer)
 150                 goto exit;
 151
 152         obj = buffer.pointer;
 153         if (obj->type != ACPI_TYPE_BUFFER ||
 154             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 155                 goto exit;
 156         }
 157
 158         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 159         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 160                 map_lapic_id(header, acpi_id, &apic_id);
 161         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 162                 map_lsapic_id(header, type, acpi_id, &apic_id);
 163         } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 164                 map_gic_id(header, type, acpi_id, &apic_id);
 165         }
 166
 167 exit:
 168         kfree(buffer.pointer);
 169         return apic_id;
 170 }
 171
 172 int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
 173 {
 174         int apic_id;
 175
 176         apic_id = map_mat_entry(handle, type, acpi_id);
 177         if (apic_id == -1)
 178                 apic_id = map_madt_entry(type, acpi_id);
 179
 180         return apic_id;
 181 }
 182
 183 int acpi_map_cpuid(int apic_id, u32 acpi_id)
 184 {
 185 #ifdef CONFIG_SMP
 186         int i;
 187 #endif
 188
 189         if (apic_id == -1) {
 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 returns 0 for the processor
 206                  * handle with acpi id 0 if nr_cpu_ids is 1.
 207                  * This should be the case if SMP tables are not found.
 208                  * Return -1 for other CPU's handle.
 209                  */
 210                 if (nr_cpu_ids <= 1 && acpi_id == 0)
 211                         return acpi_id;
 212                 else
 213                         return apic_id;
 214         }
 215
 216 #ifdef CONFIG_SMP
 217         for_each_possible_cpu(i) {
 218                 if (cpu_physical_id(i) == apic_id)
 219                         return i;
 220         }
 221 #else
 222         /* In UP kernel, only processor 0 is valid */
 223         if (apic_id == 0)
 224                 return apic_id;
 225 #endif
 226         return -1;
 227 }
 228
 229 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 230 {
 231         int apic_id;
 232
 233         apic_id = acpi_get_apicid(handle, type, acpi_id);
 234
 235         return acpi_map_cpuid(apic_id, acpi_id);
 236 }
 237 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 238
 239 static bool __init processor_physically_present(acpi_handle handle)
 240 {
 241         int cpuid, type;
 242         u32 acpi_id;
 243         acpi_status status;
 244         acpi_object_type acpi_type;
 245         unsigned long long tmp;
 246         union acpi_object object = { 0 };
 247         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 248
 249         status = acpi_get_type(handle, &acpi_type);
 250         if (ACPI_FAILURE(status))
 251                 return false;
 252
 253         switch (acpi_type) {
 254         case ACPI_TYPE_PROCESSOR:
 255                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 256                 if (ACPI_FAILURE(status))
 257                         return false;
 258                 acpi_id = object.processor.proc_id;
 259                 break;
 260         case ACPI_TYPE_DEVICE:
 261                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 262                 if (ACPI_FAILURE(status))
 263                         return false;
 264                 acpi_id = tmp;
 265                 break;
 266         default:
 267                 return false;
 268         }
 269
 270         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 271         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 272
 273         if (cpuid == -1)
 274                 return false;
 275
 276         return true;
 277 }
 278
 279 static void acpi_set_pdc_bits(u32 *buf)
 280 {
 281         buf[0] = ACPI_PDC_REVISION_ID;
 282         buf[1] = 1;
 283
 284         /* Enable coordination with firmware's _TSD info */
 285         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 286
 287         /* Twiddle arch-specific bits needed for _PDC */
 288         arch_acpi_set_pdc_bits(buf);
 289 }
 290
 291 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 292 {
 293         struct acpi_object_list *obj_list;
 294         union acpi_object *obj;
 295         u32 *buf;
 296
 297         /* allocate and initialize pdc. It will be used later. */
 298         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 299         if (!obj_list) {
 300                 printk(KERN_ERR "Memory allocation error\n");
 301                 return NULL;
 302         }
 303
 304         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 305         if (!obj) {
 306                 printk(KERN_ERR "Memory allocation error\n");
 307                 kfree(obj_list);
 308                 return NULL;
 309         }
 310
 311         buf = kmalloc(12, GFP_KERNEL);
 312         if (!buf) {
 313                 printk(KERN_ERR "Memory allocation error\n");
 314                 kfree(obj);
 315                 kfree(obj_list);
 316                 return NULL;
 317         }
 318
 319         acpi_set_pdc_bits(buf);
 320
 321         obj->type = ACPI_TYPE_BUFFER;
 322         obj->buffer.length = 12;
 323         obj->buffer.pointer = (u8 *) buf;
 324         obj_list->count = 1;
 325         obj_list->pointer = obj;
 326
 327         return obj_list;
 328 }
 329
 330 /*
 331  * _PDC is required for a BIOS-OS handshake for most of the newer
 332  * ACPI processor features.
 333  */
 334 static acpi_status
 335 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 336 {
 337         acpi_status status = AE_OK;
 338
 339         if (boot_option_idle_override == IDLE_NOMWAIT) {
 340                 /*
 341                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 342                  * mode will be disabled in the parameter of _PDC object.
 343                  * Of course C1_FFH access mode will also be disabled.
 344                  */
 345                 union acpi_object *obj;
 346                 u32 *buffer = NULL;
 347
 348                 obj = pdc_in->pointer;
 349                 buffer = (u32 *)(obj->buffer.pointer);
 350                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 351
 352         }
 353         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 354
 355         if (ACPI_FAILURE(status))
 356                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 357                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 358
 359         return status;
 360 }
 361
 362 void acpi_processor_set_pdc(acpi_handle handle)
 363 {
 364         struct acpi_object_list *obj_list;
 365
 366         if (arch_has_acpi_pdc() == false)
 367                 return;
 368
 369         obj_list = acpi_processor_alloc_pdc();
 370         if (!obj_list)
 371                 return;
 372
 373         acpi_processor_eval_pdc(handle, obj_list);
 374
 375         kfree(obj_list->pointer->buffer.pointer);
 376         kfree(obj_list->pointer);
 377         kfree(obj_list);
 378 }
 379
 380 static acpi_status __init
 381 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 382 {
 383         if (processor_physically_present(handle) == false)
 384                 return AE_OK;
 385
 386         acpi_processor_set_pdc(handle);
 387         return AE_OK;
 388 }
 389
 390 #if defined(CONFIG_X86) || defined(CONFIG_IA64)
 391 static int __init set_no_mwait(const struct dmi_system_id *id)
 392 {
 393         pr_notice(PREFIX "%s detected - disabling mwait for CPU C-states\n",
 394                   id->ident);
 395         boot_option_idle_override = IDLE_NOMWAIT;
 396         return 0;
 397 }
 398
 399 static struct dmi_system_id processor_idle_dmi_table[] __initdata = {
 400         {
 401         set_no_mwait, "Extensa 5220", {
 402         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
 403         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 404         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
 405         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
 406         {},
 407 };
 408
 409 static void __init processor_dmi_check(void)
 410 {
 411         /*
 412          * Check whether the system is DMI table. If yes, OSPM
 413          * should not use mwait for CPU-states.
 414          */
 415         dmi_check_system(processor_idle_dmi_table);
 416 }
 417 #else
 418 static inline void processor_dmi_check(void) {}
 419 #endif
 420
 421 void __init acpi_early_processor_set_pdc(void)
 422 {
 423         processor_dmi_check();
 424
 425         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 426                             ACPI_UINT32_MAX,
 427                             early_init_pdc, NULL, NULL, NULL);
 428         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL);
 429 }