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_madt_entry(int type, u32 acpi_id)
  75 {
  76         unsigned long madt_end, entry;
  77         static struct acpi_table_madt *madt;
  78         static int read_madt;
  79         int apic_id = -1;
  80
  81         if (!read_madt) {
  82                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
  83                                         (struct acpi_table_header **)&madt)))
  84                         madt = NULL;
  85                 read_madt++;
  86         }
  87
  88         if (!madt)
  89                 return apic_id;
  90
  91         entry = (unsigned long)madt;
  92         madt_end = entry + madt->header.length;
  93
  94         /* Parse all entries looking for a match. */
  95
  96         entry += sizeof(struct acpi_table_madt);
  97         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
  98                 struct acpi_subtable_header *header =
  99                         (struct acpi_subtable_header *)entry;
 100                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 101                         if (!map_lapic_id(header, acpi_id, &apic_id))
 102                                 break;
 103                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 104                         if (!map_x2apic_id(header, type, acpi_id, &apic_id))
 105                                 break;
 106                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 107                         if (!map_lsapic_id(header, type, acpi_id, &apic_id))
 108                                 break;
 109                 }
 110                 entry += header->length;
 111         }
 112         return apic_id;
 113 }
 114
 115 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 116 {
 117         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 118         union acpi_object *obj;
 119         struct acpi_subtable_header *header;
 120         int apic_id = -1;
 121
 122         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 123                 goto exit;
 124
 125         if (!buffer.length || !buffer.pointer)
 126                 goto exit;
 127
 128         obj = buffer.pointer;
 129         if (obj->type != ACPI_TYPE_BUFFER ||
 130             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 131                 goto exit;
 132         }
 133
 134         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 135         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 136                 map_lapic_id(header, acpi_id, &apic_id);
 137         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 138                 map_lsapic_id(header, type, acpi_id, &apic_id);
 139         }
 140
 141 exit:
 142         kfree(buffer.pointer);
 143         return apic_id;
 144 }
 145
 146 int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
 147 {
 148         int apic_id;
 149
 150         apic_id = map_mat_entry(handle, type, acpi_id);
 151         if (apic_id == -1)
 152                 apic_id = map_madt_entry(type, acpi_id);
 153
 154         return apic_id;
 155 }
 156
 157 int acpi_map_cpuid(int apic_id, u32 acpi_id)
 158 {
 159 #ifdef CONFIG_SMP
 160         int i;
 161 #endif
 162
 163         if (apic_id == -1) {
 164                 /*
 165                  * On UP processor, there is no _MAT or MADT table.
 166                  * So above apic_id is always set to -1.
 167                  *
 168                  * BIOS may define multiple CPU handles even for UP processor.
 169                  * For example,
 170                  *
 171                  * Scope (_PR)
 172                  * {
 173                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 174                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 175                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 176                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 177                  * }
 178                  *
 179                  * Ignores apic_id and always returns 0 for the processor
 180                  * handle with acpi id 0 if nr_cpu_ids is 1.
 181                  * This should be the case if SMP tables are not found.
 182                  * Return -1 for other CPU's handle.
 183                  */
 184                 if (nr_cpu_ids <= 1 && acpi_id == 0)
 185                         return acpi_id;
 186                 else
 187                         return apic_id;
 188         }
 189
 190 #ifdef CONFIG_SMP
 191         for_each_possible_cpu(i) {
 192                 if (cpu_physical_id(i) == apic_id)
 193                         return i;
 194         }
 195 #else
 196         /* In UP kernel, only processor 0 is valid */
 197         if (apic_id == 0)
 198                 return apic_id;
 199 #endif
 200         return -1;
 201 }
 202
 203 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 204 {
 205         int apic_id;
 206
 207         apic_id = acpi_get_apicid(handle, type, acpi_id);
 208
 209         return acpi_map_cpuid(apic_id, acpi_id);
 210 }
 211 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 212
 213 static bool __init processor_physically_present(acpi_handle handle)
 214 {
 215         int cpuid, type;
 216         u32 acpi_id;
 217         acpi_status status;
 218         acpi_object_type acpi_type;
 219         unsigned long long tmp;
 220         union acpi_object object = { 0 };
 221         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 222
 223         status = acpi_get_type(handle, &acpi_type);
 224         if (ACPI_FAILURE(status))
 225                 return false;
 226
 227         switch (acpi_type) {
 228         case ACPI_TYPE_PROCESSOR:
 229                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 230                 if (ACPI_FAILURE(status))
 231                         return false;
 232                 acpi_id = object.processor.proc_id;
 233                 break;
 234         case ACPI_TYPE_DEVICE:
 235                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 236                 if (ACPI_FAILURE(status))
 237                         return false;
 238                 acpi_id = tmp;
 239                 break;
 240         default:
 241                 return false;
 242         }
 243
 244         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 245         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 246
 247         if (cpuid == -1)
 248                 return false;
 249
 250         return true;
 251 }
 252
 253 static void acpi_set_pdc_bits(u32 *buf)
 254 {
 255         buf[0] = ACPI_PDC_REVISION_ID;
 256         buf[1] = 1;
 257
 258         /* Enable coordination with firmware's _TSD info */
 259         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 260
 261         /* Twiddle arch-specific bits needed for _PDC */
 262         arch_acpi_set_pdc_bits(buf);
 263 }
 264
 265 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 266 {
 267         struct acpi_object_list *obj_list;
 268         union acpi_object *obj;
 269         u32 *buf;
 270
 271         /* allocate and initialize pdc. It will be used later. */
 272         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 273         if (!obj_list) {
 274                 printk(KERN_ERR "Memory allocation error\n");
 275                 return NULL;
 276         }
 277
 278         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 279         if (!obj) {
 280                 printk(KERN_ERR "Memory allocation error\n");
 281                 kfree(obj_list);
 282                 return NULL;
 283         }
 284
 285         buf = kmalloc(12, GFP_KERNEL);
 286         if (!buf) {
 287                 printk(KERN_ERR "Memory allocation error\n");
 288                 kfree(obj);
 289                 kfree(obj_list);
 290                 return NULL;
 291         }
 292
 293         acpi_set_pdc_bits(buf);
 294
 295         obj->type = ACPI_TYPE_BUFFER;
 296         obj->buffer.length = 12;
 297         obj->buffer.pointer = (u8 *) buf;
 298         obj_list->count = 1;
 299         obj_list->pointer = obj;
 300
 301         return obj_list;
 302 }
 303
 304 /*
 305  * _PDC is required for a BIOS-OS handshake for most of the newer
 306  * ACPI processor features.
 307  */
 308 static acpi_status
 309 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 310 {
 311         acpi_status status = AE_OK;
 312
 313         if (boot_option_idle_override == IDLE_NOMWAIT) {
 314                 /*
 315                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 316                  * mode will be disabled in the parameter of _PDC object.
 317                  * Of course C1_FFH access mode will also be disabled.
 318                  */
 319                 union acpi_object *obj;
 320                 u32 *buffer = NULL;
 321
 322                 obj = pdc_in->pointer;
 323                 buffer = (u32 *)(obj->buffer.pointer);
 324                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 325
 326         }
 327         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 328
 329         if (ACPI_FAILURE(status))
 330                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 331                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 332
 333         return status;
 334 }
 335
 336 void acpi_processor_set_pdc(acpi_handle handle)
 337 {
 338         struct acpi_object_list *obj_list;
 339
 340         if (arch_has_acpi_pdc() == false)
 341                 return;
 342
 343         obj_list = acpi_processor_alloc_pdc();
 344         if (!obj_list)
 345                 return;
 346
 347         acpi_processor_eval_pdc(handle, obj_list);
 348
 349         kfree(obj_list->pointer->buffer.pointer);
 350         kfree(obj_list->pointer);
 351         kfree(obj_list);
 352 }
 353
 354 static acpi_status __init
 355 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 356 {
 357         if (processor_physically_present(handle) == false)
 358                 return AE_OK;
 359
 360         acpi_processor_set_pdc(handle);
 361         return AE_OK;
 362 }
 363
 364 #if defined(CONFIG_X86) || defined(CONFIG_IA64)
 365 static int __init set_no_mwait(const struct dmi_system_id *id)
 366 {
 367         pr_notice(PREFIX "%s detected - disabling mwait for CPU C-states\n",
 368                   id->ident);
 369         boot_option_idle_override = IDLE_NOMWAIT;
 370         return 0;
 371 }
 372
 373 static struct dmi_system_id processor_idle_dmi_table[] __initdata = {
 374         {
 375         set_no_mwait, "Extensa 5220", {
 376         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
 377         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 378         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
 379         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
 380         {},
 381 };
 382
 383 static void __init processor_dmi_check(void)
 384 {
 385         /*
 386          * Check whether the system is DMI table. If yes, OSPM
 387          * should not use mwait for CPU-states.
 388          */
 389         dmi_check_system(processor_idle_dmi_table);
 390 }
 391 #else
 392 static inline void processor_dmi_check(void) {}
 393 #endif
 394
 395 void __init acpi_early_processor_set_pdc(void)
 396 {
 397         processor_dmi_check();
 398
 399         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 400                             ACPI_UINT32_MAX,
 401                             early_init_pdc, NULL, NULL, NULL);
 402         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, early_init_pdc, NULL, NULL);
 403 }