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/dmi.h>
  11
  12 #include <acpi/acpi_drivers.h>
  13 #include <acpi/processor.h>
  14
  15 #include "internal.h"
  16
  17 #define PREFIX                  "ACPI: "
  18 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  19 ACPI_MODULE_NAME("processor_core");
  20
  21 static int set_no_mwait(const struct dmi_system_id *id)
  22 {
  23         printk(KERN_NOTICE PREFIX "%s detected - "
  24                 "disabling mwait for CPU C-states\n", id->ident);
  25         idle_nomwait = 1;
  26         return 0;
  27 }
  28
  29 static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
  30         {
  31         set_no_mwait, "IFL91 board", {
  32         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
  33         DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
  34         DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
  35         DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
  36         {
  37         set_no_mwait, "Extensa 5220", {
  38         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
  39         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
  40         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
  41         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
  42         {},
  43 };
  44
  45 #ifdef CONFIG_SMP
  46 static int map_lapic_id(struct acpi_subtable_header *entry,
  47                  u32 acpi_id, int *apic_id)
  48 {
  49         struct acpi_madt_local_apic *lapic =
  50                 (struct acpi_madt_local_apic *)entry;
  51
  52         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  53                 return 0;
  54
  55         if (lapic->processor_id != acpi_id)
  56                 return 0;
  57
  58         *apic_id = lapic->id;
  59         return 1;
  60 }
  61
  62 static int map_x2apic_id(struct acpi_subtable_header *entry,
  63                          int device_declaration, u32 acpi_id, int *apic_id)
  64 {
  65         struct acpi_madt_local_x2apic *apic =
  66                 (struct acpi_madt_local_x2apic *)entry;
  67
  68         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  69                 return 0;
  70
  71         if (device_declaration && (apic->uid == acpi_id)) {
  72                 *apic_id = apic->local_apic_id;
  73                 return 1;
  74         }
  75
  76         return 0;
  77 }
  78
  79 static int map_lsapic_id(struct acpi_subtable_header *entry,
  80                 int device_declaration, u32 acpi_id, int *apic_id)
  81 {
  82         struct acpi_madt_local_sapic *lsapic =
  83                 (struct acpi_madt_local_sapic *)entry;
  84
  85         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  86                 return 0;
  87
  88         if (device_declaration) {
  89                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  90                         return 0;
  91         } else if (lsapic->processor_id != acpi_id)
  92                 return 0;
  93
  94         *apic_id = (lsapic->id << 8) | lsapic->eid;
  95         return 1;
  96 }
  97
  98 static int map_madt_entry(int type, u32 acpi_id)
  99 {
 100         unsigned long madt_end, entry;
 101         static struct acpi_table_madt *madt;
 102         static int read_madt;
 103         int apic_id = -1;
 104
 105         if (!read_madt) {
 106                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 107                                         (struct acpi_table_header **)&madt)))
 108                         madt = NULL;
 109                 read_madt++;
 110         }
 111
 112         if (!madt)
 113                 return apic_id;
 114
 115         entry = (unsigned long)madt;
 116         madt_end = entry + madt->header.length;
 117
 118         /* Parse all entries looking for a match. */
 119
 120         entry += sizeof(struct acpi_table_madt);
 121         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 122                 struct acpi_subtable_header *header =
 123                         (struct acpi_subtable_header *)entry;
 124                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 125                         if (map_lapic_id(header, acpi_id, &apic_id))
 126                                 break;
 127                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 128                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
 129                                 break;
 130                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 131                         if (map_lsapic_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         }
 164
 165 exit:
 166         if (buffer.pointer)
 167                 kfree(buffer.pointer);
 168         return apic_id;
 169 }
 170
 171 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 172 {
 173         int i;
 174         int apic_id = -1;
 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         if (apic_id == -1)
 180                 return apic_id;
 181
 182         for_each_possible_cpu(i) {
 183                 if (cpu_physical_id(i) == apic_id)
 184                         return i;
 185         }
 186         return -1;
 187 }
 188 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 189 #endif
 190
 191 static bool processor_physically_present(acpi_handle handle)
 192 {
 193         int cpuid, type;
 194         u32 acpi_id;
 195         acpi_status status;
 196         acpi_object_type acpi_type;
 197         unsigned long long tmp;
 198         union acpi_object object = { 0 };
 199         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 200
 201         status = acpi_get_type(handle, &acpi_type);
 202         if (ACPI_FAILURE(status))
 203                 return false;
 204
 205         switch (acpi_type) {
 206         case ACPI_TYPE_PROCESSOR:
 207                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 208                 if (ACPI_FAILURE(status))
 209                         return false;
 210                 acpi_id = object.processor.proc_id;
 211                 break;
 212         case ACPI_TYPE_DEVICE:
 213                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 214                 if (ACPI_FAILURE(status))
 215                         return false;
 216                 acpi_id = tmp;
 217                 break;
 218         default:
 219                 return false;
 220         }
 221
 222         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 223         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 224
 225         if (cpuid == -1)
 226                 return false;
 227
 228         return true;
 229 }
 230
 231 static void acpi_set_pdc_bits(u32 *buf)
 232 {
 233         buf[0] = ACPI_PDC_REVISION_ID;
 234         buf[1] = 1;
 235
 236         /* Enable coordination with firmware's _TSD info */
 237         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 238
 239         /* Twiddle arch-specific bits needed for _PDC */
 240         arch_acpi_set_pdc_bits(buf);
 241 }
 242
 243 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 244 {
 245         struct acpi_object_list *obj_list;
 246         union acpi_object *obj;
 247         u32 *buf;
 248
 249         /* allocate and initialize pdc. It will be used later. */
 250         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 251         if (!obj_list) {
 252                 printk(KERN_ERR "Memory allocation error\n");
 253                 return NULL;
 254         }
 255
 256         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 257         if (!obj) {
 258                 printk(KERN_ERR "Memory allocation error\n");
 259                 kfree(obj_list);
 260                 return NULL;
 261         }
 262
 263         buf = kmalloc(12, GFP_KERNEL);
 264         if (!buf) {
 265                 printk(KERN_ERR "Memory allocation error\n");
 266                 kfree(obj);
 267                 kfree(obj_list);
 268                 return NULL;
 269         }
 270
 271         acpi_set_pdc_bits(buf);
 272
 273         obj->type = ACPI_TYPE_BUFFER;
 274         obj->buffer.length = 12;
 275         obj->buffer.pointer = (u8 *) buf;
 276         obj_list->count = 1;
 277         obj_list->pointer = obj;
 278
 279         return obj_list;
 280 }
 281
 282 /*
 283  * _PDC is required for a BIOS-OS handshake for most of the newer
 284  * ACPI processor features.
 285  */
 286 static int
 287 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 288 {
 289         acpi_status status = AE_OK;
 290
 291         if (idle_nomwait) {
 292                 /*
 293                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 294                  * mode will be disabled in the parameter of _PDC object.
 295                  * Of course C1_FFH access mode will also be disabled.
 296                  */
 297                 union acpi_object *obj;
 298                 u32 *buffer = NULL;
 299
 300                 obj = pdc_in->pointer;
 301                 buffer = (u32 *)(obj->buffer.pointer);
 302                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 303
 304         }
 305         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 306
 307         if (ACPI_FAILURE(status))
 308                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 309                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 310
 311         return status;
 312 }
 313
 314 void acpi_processor_set_pdc(acpi_handle handle)
 315 {
 316         struct acpi_object_list *obj_list;
 317
 318         if (arch_has_acpi_pdc() == false)
 319                 return;
 320
 321         obj_list = acpi_processor_alloc_pdc();
 322         if (!obj_list)
 323                 return;
 324
 325         acpi_processor_eval_pdc(handle, obj_list);
 326
 327         kfree(obj_list->pointer->buffer.pointer);
 328         kfree(obj_list->pointer);
 329         kfree(obj_list);
 330 }
 331 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
 332
 333 static acpi_status
 334 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 335 {
 336         if (processor_physically_present(handle) == false)
 337                 return AE_OK;
 338
 339         acpi_processor_set_pdc(handle);
 340         return AE_OK;
 341 }
 342
 343 void __init acpi_early_processor_set_pdc(void)
 344 {
 345         /*
 346          * Check whether the system is DMI table. If yes, OSPM
 347          * should not use mwait for CPU-states.
 348          */
 349         dmi_check_system(processor_idle_dmi_table);
 350
 351         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 352                             ACPI_UINT32_MAX,
 353                             early_init_pdc, NULL, NULL, NULL);
 354 }