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_madt_entry(int type, u32 acpi_id)
  74 {
  75         unsigned long madt_end, entry;
  76         static struct acpi_table_madt *madt;
  77         static int read_madt;
  78         int apic_id = -1;
  79
  80         if (!read_madt) {
  81                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
  82                                         (struct acpi_table_header **)&madt)))
  83                         madt = NULL;
  84                 read_madt++;
  85         }
  86
  87         if (!madt)
  88                 return apic_id;
  89
  90         entry = (unsigned long)madt;
  91         madt_end = entry + madt->header.length;
  92
  93         /* Parse all entries looking for a match. */
  94
  95         entry += sizeof(struct acpi_table_madt);
  96         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
  97                 struct acpi_subtable_header *header =
  98                         (struct acpi_subtable_header *)entry;
  99                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 100                         if (!map_lapic_id(header, acpi_id, &apic_id))
 101                                 break;
 102                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 103                         if (!map_x2apic_id(header, type, acpi_id, &apic_id))
 104                                 break;
 105                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 106                         if (!map_lsapic_id(header, type, acpi_id, &apic_id))
 107                                 break;
 108                 }
 109                 entry += header->length;
 110         }
 111         return apic_id;
 112 }
 113
 114 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 115 {
 116         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 117         union acpi_object *obj;
 118         struct acpi_subtable_header *header;
 119         int apic_id = -1;
 120
 121         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 122                 goto exit;
 123
 124         if (!buffer.length || !buffer.pointer)
 125                 goto exit;
 126
 127         obj = buffer.pointer;
 128         if (obj->type != ACPI_TYPE_BUFFER ||
 129             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 130                 goto exit;
 131         }
 132
 133         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 134         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 135                 map_lapic_id(header, acpi_id, &apic_id);
 136         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 137                 map_lsapic_id(header, type, acpi_id, &apic_id);
 138         }
 139
 140 exit:
 141         kfree(buffer.pointer);
 142         return apic_id;
 143 }
 144
 145 int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
 146 {
 147         int apic_id;
 148
 149         apic_id = map_mat_entry(handle, type, acpi_id);
 150         if (apic_id == -1)
 151                 apic_id = map_madt_entry(type, acpi_id);
 152
 153         return apic_id;
 154 }
 155
 156 int acpi_map_cpuid(int apic_id, u32 acpi_id)
 157 {
 158 #ifdef CONFIG_SMP
 159         int i;
 160 #endif
 161
 162         if (apic_id == -1) {
 163                 /*
 164                  * On UP processor, there is no _MAT or MADT table.
 165                  * So above apic_id is always set to -1.
 166                  *
 167                  * BIOS may define multiple CPU handles even for UP processor.
 168                  * For example,
 169                  *
 170                  * Scope (_PR)
 171                  * {
 172                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 173                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 174                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 175                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 176                  * }
 177                  *
 178                  * Ignores apic_id and always returns 0 for the processor
 179                  * handle with acpi id 0 if nr_cpu_ids is 1.
 180                  * This should be the case if SMP tables are not found.
 181                  * Return -1 for other CPU's handle.
 182                  */
 183                 if (nr_cpu_ids <= 1 && acpi_id == 0)
 184                         return acpi_id;
 185                 else
 186                         return apic_id;
 187         }
 188
 189 #ifdef CONFIG_SMP
 190         for_each_possible_cpu(i) {
 191                 if (cpu_physical_id(i) == apic_id)
 192                         return i;
 193         }
 194 #else
 195         /* In UP kernel, only processor 0 is valid */
 196         if (apic_id == 0)
 197                 return apic_id;
 198 #endif
 199         return -1;
 200 }
 201
 202 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 203 {
 204         int apic_id;
 205
 206         apic_id = acpi_get_apicid(handle, type, acpi_id);
 207
 208         return acpi_map_cpuid(apic_id, acpi_id);
 209 }
 210 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 211
 212 static bool __init processor_physically_present(acpi_handle handle)
 213 {
 214         int cpuid, type;
 215         u32 acpi_id;
 216         acpi_status status;
 217         acpi_object_type acpi_type;
 218         unsigned long long tmp;
 219         union acpi_object object = { 0 };
 220         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 221
 222         status = acpi_get_type(handle, &acpi_type);
 223         if (ACPI_FAILURE(status))
 224                 return false;
 225
 226         switch (acpi_type) {
 227         case ACPI_TYPE_PROCESSOR:
 228                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 229                 if (ACPI_FAILURE(status))
 230                         return false;
 231                 acpi_id = object.processor.proc_id;
 232                 break;
 233         case ACPI_TYPE_DEVICE:
 234                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 235                 if (ACPI_FAILURE(status))
 236                         return false;
 237                 acpi_id = tmp;
 238                 break;
 239         default:
 240                 return false;
 241         }
 242
 243         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 244         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 245
 246         if (cpuid == -1)
 247                 return false;
 248
 249         return true;
 250 }
 251
 252 static void acpi_set_pdc_bits(u32 *buf)
 253 {
 254         buf[0] = ACPI_PDC_REVISION_ID;
 255         buf[1] = 1;
 256
 257         /* Enable coordination with firmware's _TSD info */
 258         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 259
 260         /* Twiddle arch-specific bits needed for _PDC */
 261         arch_acpi_set_pdc_bits(buf);
 262 }
 263
 264 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 265 {
 266         struct acpi_object_list *obj_list;
 267         union acpi_object *obj;
 268         u32 *buf;
 269
 270         /* allocate and initialize pdc. It will be used later. */
 271         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 272         if (!obj_list) {
 273                 printk(KERN_ERR "Memory allocation error\n");
 274                 return NULL;
 275         }
 276
 277         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 278         if (!obj) {
 279                 printk(KERN_ERR "Memory allocation error\n");
 280                 kfree(obj_list);
 281                 return NULL;
 282         }
 283
 284         buf = kmalloc(12, GFP_KERNEL);
 285         if (!buf) {
 286                 printk(KERN_ERR "Memory allocation error\n");
 287                 kfree(obj);
 288                 kfree(obj_list);
 289                 return NULL;
 290         }
 291
 292         acpi_set_pdc_bits(buf);
 293
 294         obj->type = ACPI_TYPE_BUFFER;
 295         obj->buffer.length = 12;
 296         obj->buffer.pointer = (u8 *) buf;
 297         obj_list->count = 1;
 298         obj_list->pointer = obj;
 299
 300         return obj_list;
 301 }
 302
 303 /*
 304  * _PDC is required for a BIOS-OS handshake for most of the newer
 305  * ACPI processor features.
 306  */
 307 static acpi_status
 308 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 309 {
 310         acpi_status status = AE_OK;
 311
 312         if (boot_option_idle_override == IDLE_NOMWAIT) {
 313                 /*
 314                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 315                  * mode will be disabled in the parameter of _PDC object.
 316                  * Of course C1_FFH access mode will also be disabled.
 317                  */
 318                 union acpi_object *obj;
 319                 u32 *buffer = NULL;
 320
 321                 obj = pdc_in->pointer;
 322                 buffer = (u32 *)(obj->buffer.pointer);
 323                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 324
 325         }
 326         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 327
 328         if (ACPI_FAILURE(status))
 329                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 330                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 331
 332         return status;
 333 }
 334
 335 void acpi_processor_set_pdc(acpi_handle handle)
 336 {
 337         struct acpi_object_list *obj_list;
 338
 339         if (arch_has_acpi_pdc() == false)
 340                 return;
 341
 342         obj_list = acpi_processor_alloc_pdc();
 343         if (!obj_list)
 344                 return;
 345
 346         acpi_processor_eval_pdc(handle, obj_list);
 347
 348         kfree(obj_list->pointer->buffer.pointer);
 349         kfree(obj_list->pointer);
 350         kfree(obj_list);
 351 }
 352
 353 static acpi_status __init
 354 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 355 {
 356         if (processor_physically_present(handle) == false)
 357                 return AE_OK;
 358
 359         acpi_processor_set_pdc(handle);
 360         return AE_OK;
 361 }
 362
 363 #if defined(CONFIG_X86) || defined(CONFIG_IA64)
 364 static int __init set_no_mwait(const struct dmi_system_id *id)
 365 {
 366         pr_notice(PREFIX "%s detected - disabling mwait for CPU C-states\n",
 367                   id->ident);
 368         boot_option_idle_override = IDLE_NOMWAIT;
 369         return 0;
 370 }
 371
 372 static struct dmi_system_id processor_idle_dmi_table[] __initdata = {
 373         {
 374         set_no_mwait, "Extensa 5220", {
 375         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
 376         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 377         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
 378         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
 379         {},
 380 };
 381
 382 static void __init processor_dmi_check(void)
 383 {
 384         /*
 385          * Check whether the system is DMI table. If yes, OSPM
 386          * should not use mwait for CPU-states.
 387          */
 388         dmi_check_system(processor_idle_dmi_table);
 389 }
 390 #else
 391 static inline void processor_dmi_check(void) {}
 392 #endif
 393
 394 void __init acpi_early_processor_set_pdc(void)
 395 {
 396         processor_dmi_check();
 397
 398         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 399                             ACPI_UINT32_MAX,
 400                             early_init_pdc, NULL, NULL, NULL);
 401         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL);
 402 }