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 #include <linux/slab.h>
  12
  13 #include <acpi/acpi_drivers.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 set_no_mwait(const struct dmi_system_id *id)
  23 {
  24         printk(KERN_NOTICE PREFIX "%s detected - "
  25                 "disabling mwait for CPU C-states\n", id->ident);
  26         idle_nomwait = 1;
  27         return 0;
  28 }
  29
  30 static struct dmi_system_id __cpuinitdata processor_idle_dmi_table[] = {
  31         {
  32         set_no_mwait, "IFL91 board", {
  33         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
  34         DMI_MATCH(DMI_SYS_VENDOR, "ZEPTO"),
  35         DMI_MATCH(DMI_PRODUCT_VERSION, "3215W"),
  36         DMI_MATCH(DMI_BOARD_NAME, "IFL91") }, NULL},
  37         {
  38         set_no_mwait, "Extensa 5220", {
  39         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
  40         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
  41         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
  42         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
  43         {},
  44 };
  45
  46 #ifdef CONFIG_SMP
  47 static int map_lapic_id(struct acpi_subtable_header *entry,
  48                  u32 acpi_id, int *apic_id)
  49 {
  50         struct acpi_madt_local_apic *lapic =
  51                 (struct acpi_madt_local_apic *)entry;
  52
  53         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  54                 return 0;
  55
  56         if (lapic->processor_id != acpi_id)
  57                 return 0;
  58
  59         *apic_id = lapic->id;
  60         return 1;
  61 }
  62
  63 static int map_x2apic_id(struct acpi_subtable_header *entry,
  64                          int device_declaration, u32 acpi_id, int *apic_id)
  65 {
  66         struct acpi_madt_local_x2apic *apic =
  67                 (struct acpi_madt_local_x2apic *)entry;
  68
  69         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  70                 return 0;
  71
  72         if (device_declaration && (apic->uid == acpi_id)) {
  73                 *apic_id = apic->local_apic_id;
  74                 return 1;
  75         }
  76
  77         return 0;
  78 }
  79
  80 static int map_lsapic_id(struct acpi_subtable_header *entry,
  81                 int device_declaration, u32 acpi_id, int *apic_id)
  82 {
  83         struct acpi_madt_local_sapic *lsapic =
  84                 (struct acpi_madt_local_sapic *)entry;
  85
  86         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  87                 return 0;
  88
  89         if (device_declaration) {
  90                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  91                         return 0;
  92         } else if (lsapic->processor_id != acpi_id)
  93                 return 0;
  94
  95         *apic_id = (lsapic->id << 8) | lsapic->eid;
  96         return 1;
  97 }
  98
  99 static int map_madt_entry(int type, u32 acpi_id)
 100 {
 101         unsigned long madt_end, entry;
 102         static struct acpi_table_madt *madt;
 103         static int read_madt;
 104         int apic_id = -1;
 105
 106         if (!read_madt) {
 107                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 108                                         (struct acpi_table_header **)&madt)))
 109                         madt = NULL;
 110                 read_madt++;
 111         }
 112
 113         if (!madt)
 114                 return apic_id;
 115
 116         entry = (unsigned long)madt;
 117         madt_end = entry + madt->header.length;
 118
 119         /* Parse all entries looking for a match. */
 120
 121         entry += sizeof(struct acpi_table_madt);
 122         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 123                 struct acpi_subtable_header *header =
 124                         (struct acpi_subtable_header *)entry;
 125                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 126                         if (map_lapic_id(header, acpi_id, &apic_id))
 127                                 break;
 128                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 129                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
 130                                 break;
 131                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 132                         if (map_lsapic_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         }
 165
 166 exit:
 167         if (buffer.pointer)
 168                 kfree(buffer.pointer);
 169         return apic_id;
 170 }
 171
 172 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 173 {
 174         int i;
 175         int apic_id = -1;
 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         if (apic_id == -1)
 181                 return apic_id;
 182
 183         for_each_possible_cpu(i) {
 184                 if (cpu_physical_id(i) == apic_id)
 185                         return i;
 186         }
 187         return -1;
 188 }
 189 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 190 #endif
 191
 192 static bool processor_physically_present(acpi_handle handle)
 193 {
 194         int cpuid, type;
 195         u32 acpi_id;
 196         acpi_status status;
 197         acpi_object_type acpi_type;
 198         unsigned long long tmp;
 199         union acpi_object object = { 0 };
 200         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 201
 202         status = acpi_get_type(handle, &acpi_type);
 203         if (ACPI_FAILURE(status))
 204                 return false;
 205
 206         switch (acpi_type) {
 207         case ACPI_TYPE_PROCESSOR:
 208                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 209                 if (ACPI_FAILURE(status))
 210                         return false;
 211                 acpi_id = object.processor.proc_id;
 212                 break;
 213         case ACPI_TYPE_DEVICE:
 214                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 215                 if (ACPI_FAILURE(status))
 216                         return false;
 217                 acpi_id = tmp;
 218                 break;
 219         default:
 220                 return false;
 221         }
 222
 223         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 224         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 225
 226         if ((cpuid == -1) && (num_possible_cpus() > 1))
 227                 return false;
 228
 229         return true;
 230 }
 231
 232 static void acpi_set_pdc_bits(u32 *buf)
 233 {
 234         buf[0] = ACPI_PDC_REVISION_ID;
 235         buf[1] = 1;
 236
 237         /* Enable coordination with firmware's _TSD info */
 238         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 239
 240         /* Twiddle arch-specific bits needed for _PDC */
 241         arch_acpi_set_pdc_bits(buf);
 242 }
 243
 244 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 245 {
 246         struct acpi_object_list *obj_list;
 247         union acpi_object *obj;
 248         u32 *buf;
 249
 250         /* allocate and initialize pdc. It will be used later. */
 251         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 252         if (!obj_list) {
 253                 printk(KERN_ERR "Memory allocation error\n");
 254                 return NULL;
 255         }
 256
 257         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 258         if (!obj) {
 259                 printk(KERN_ERR "Memory allocation error\n");
 260                 kfree(obj_list);
 261                 return NULL;
 262         }
 263
 264         buf = kmalloc(12, GFP_KERNEL);
 265         if (!buf) {
 266                 printk(KERN_ERR "Memory allocation error\n");
 267                 kfree(obj);
 268                 kfree(obj_list);
 269                 return NULL;
 270         }
 271
 272         acpi_set_pdc_bits(buf);
 273
 274         obj->type = ACPI_TYPE_BUFFER;
 275         obj->buffer.length = 12;
 276         obj->buffer.pointer = (u8 *) buf;
 277         obj_list->count = 1;
 278         obj_list->pointer = obj;
 279
 280         return obj_list;
 281 }
 282
 283 /*
 284  * _PDC is required for a BIOS-OS handshake for most of the newer
 285  * ACPI processor features.
 286  */
 287 static int
 288 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 289 {
 290         acpi_status status = AE_OK;
 291
 292         if (idle_nomwait) {
 293                 /*
 294                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 295                  * mode will be disabled in the parameter of _PDC object.
 296                  * Of course C1_FFH access mode will also be disabled.
 297                  */
 298                 union acpi_object *obj;
 299                 u32 *buffer = NULL;
 300
 301                 obj = pdc_in->pointer;
 302                 buffer = (u32 *)(obj->buffer.pointer);
 303                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 304
 305         }
 306         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 307
 308         if (ACPI_FAILURE(status))
 309                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 310                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 311
 312         return status;
 313 }
 314
 315 void acpi_processor_set_pdc(acpi_handle handle)
 316 {
 317         struct acpi_object_list *obj_list;
 318
 319         if (arch_has_acpi_pdc() == false)
 320                 return;
 321
 322         obj_list = acpi_processor_alloc_pdc();
 323         if (!obj_list)
 324                 return;
 325
 326         acpi_processor_eval_pdc(handle, obj_list);
 327
 328         kfree(obj_list->pointer->buffer.pointer);
 329         kfree(obj_list->pointer);
 330         kfree(obj_list);
 331 }
 332 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
 333
 334 static acpi_status
 335 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 336 {
 337         if (processor_physically_present(handle) == false)
 338                 return AE_OK;
 339
 340         acpi_processor_set_pdc(handle);
 341         return AE_OK;
 342 }
 343
 344 void __init acpi_early_processor_set_pdc(void)
 345 {
 346         /*
 347          * Check whether the system is DMI table. If yes, OSPM
 348          * should not use mwait for CPU-states.
 349          */
 350         dmi_check_system(processor_idle_dmi_table);
 351
 352         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 353                             ACPI_UINT32_MAX,
 354                             early_init_pdc, NULL, NULL, NULL);
 355 }