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, "Extensa 5220", {
  33         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"),
  34         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
  35         DMI_MATCH(DMI_PRODUCT_VERSION, "0100"),
  36         DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL},
  37         {},
  38 };
  39
  40 #ifdef CONFIG_SMP
  41 static int map_lapic_id(struct acpi_subtable_header *entry,
  42                  u32 acpi_id, int *apic_id)
  43 {
  44         struct acpi_madt_local_apic *lapic =
  45                 (struct acpi_madt_local_apic *)entry;
  46
  47         if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
  48                 return 0;
  49
  50         if (lapic->processor_id != acpi_id)
  51                 return 0;
  52
  53         *apic_id = lapic->id;
  54         return 1;
  55 }
  56
  57 static int map_x2apic_id(struct acpi_subtable_header *entry,
  58                          int device_declaration, u32 acpi_id, int *apic_id)
  59 {
  60         struct acpi_madt_local_x2apic *apic =
  61                 (struct acpi_madt_local_x2apic *)entry;
  62
  63         if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
  64                 return 0;
  65
  66         if (device_declaration && (apic->uid == acpi_id)) {
  67                 *apic_id = apic->local_apic_id;
  68                 return 1;
  69         }
  70
  71         return 0;
  72 }
  73
  74 static int map_lsapic_id(struct acpi_subtable_header *entry,
  75                 int device_declaration, u32 acpi_id, int *apic_id)
  76 {
  77         struct acpi_madt_local_sapic *lsapic =
  78                 (struct acpi_madt_local_sapic *)entry;
  79
  80         if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
  81                 return 0;
  82
  83         if (device_declaration) {
  84                 if ((entry->length < 16) || (lsapic->uid != acpi_id))
  85                         return 0;
  86         } else if (lsapic->processor_id != acpi_id)
  87                 return 0;
  88
  89         *apic_id = (lsapic->id << 8) | lsapic->eid;
  90         return 1;
  91 }
  92
  93 static int map_madt_entry(int type, u32 acpi_id)
  94 {
  95         unsigned long madt_end, entry;
  96         static struct acpi_table_madt *madt;
  97         static int read_madt;
  98         int apic_id = -1;
  99
 100         if (!read_madt) {
 101                 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
 102                                         (struct acpi_table_header **)&madt)))
 103                         madt = NULL;
 104                 read_madt++;
 105         }
 106
 107         if (!madt)
 108                 return apic_id;
 109
 110         entry = (unsigned long)madt;
 111         madt_end = entry + madt->header.length;
 112
 113         /* Parse all entries looking for a match. */
 114
 115         entry += sizeof(struct acpi_table_madt);
 116         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 117                 struct acpi_subtable_header *header =
 118                         (struct acpi_subtable_header *)entry;
 119                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 120                         if (map_lapic_id(header, acpi_id, &apic_id))
 121                                 break;
 122                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 123                         if (map_x2apic_id(header, type, acpi_id, &apic_id))
 124                                 break;
 125                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 126                         if (map_lsapic_id(header, type, acpi_id, &apic_id))
 127                                 break;
 128                 }
 129                 entry += header->length;
 130         }
 131         return apic_id;
 132 }
 133
 134 static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 135 {
 136         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 137         union acpi_object *obj;
 138         struct acpi_subtable_header *header;
 139         int apic_id = -1;
 140
 141         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 142                 goto exit;
 143
 144         if (!buffer.length || !buffer.pointer)
 145                 goto exit;
 146
 147         obj = buffer.pointer;
 148         if (obj->type != ACPI_TYPE_BUFFER ||
 149             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 150                 goto exit;
 151         }
 152
 153         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 154         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 155                 map_lapic_id(header, acpi_id, &apic_id);
 156         } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 157                 map_lsapic_id(header, type, acpi_id, &apic_id);
 158         }
 159
 160 exit:
 161         if (buffer.pointer)
 162                 kfree(buffer.pointer);
 163         return apic_id;
 164 }
 165
 166 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 167 {
 168         int i;
 169         int apic_id = -1;
 170
 171         apic_id = map_mat_entry(handle, type, acpi_id);
 172         if (apic_id == -1)
 173                 apic_id = map_madt_entry(type, acpi_id);
 174         if (apic_id == -1)
 175                 return apic_id;
 176
 177         for_each_possible_cpu(i) {
 178                 if (cpu_physical_id(i) == apic_id)
 179                         return i;
 180         }
 181         return -1;
 182 }
 183 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 184 #endif
 185
 186 static bool processor_physically_present(acpi_handle handle)
 187 {
 188         int cpuid, type;
 189         u32 acpi_id;
 190         acpi_status status;
 191         acpi_object_type acpi_type;
 192         unsigned long long tmp;
 193         union acpi_object object = { 0 };
 194         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 195
 196         status = acpi_get_type(handle, &acpi_type);
 197         if (ACPI_FAILURE(status))
 198                 return false;
 199
 200         switch (acpi_type) {
 201         case ACPI_TYPE_PROCESSOR:
 202                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 203                 if (ACPI_FAILURE(status))
 204                         return false;
 205                 acpi_id = object.processor.proc_id;
 206                 break;
 207         case ACPI_TYPE_DEVICE:
 208                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
 209                 if (ACPI_FAILURE(status))
 210                         return false;
 211                 acpi_id = tmp;
 212                 break;
 213         default:
 214                 return false;
 215         }
 216
 217         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 218         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 219
 220         if ((cpuid == -1) && (num_possible_cpus() > 1))
 221                 return false;
 222
 223         return true;
 224 }
 225
 226 static void acpi_set_pdc_bits(u32 *buf)
 227 {
 228         buf[0] = ACPI_PDC_REVISION_ID;
 229         buf[1] = 1;
 230
 231         /* Enable coordination with firmware's _TSD info */
 232         buf[2] = ACPI_PDC_SMP_T_SWCOORD;
 233
 234         /* Twiddle arch-specific bits needed for _PDC */
 235         arch_acpi_set_pdc_bits(buf);
 236 }
 237
 238 static struct acpi_object_list *acpi_processor_alloc_pdc(void)
 239 {
 240         struct acpi_object_list *obj_list;
 241         union acpi_object *obj;
 242         u32 *buf;
 243
 244         /* allocate and initialize pdc. It will be used later. */
 245         obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL);
 246         if (!obj_list) {
 247                 printk(KERN_ERR "Memory allocation error\n");
 248                 return NULL;
 249         }
 250
 251         obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
 252         if (!obj) {
 253                 printk(KERN_ERR "Memory allocation error\n");
 254                 kfree(obj_list);
 255                 return NULL;
 256         }
 257
 258         buf = kmalloc(12, GFP_KERNEL);
 259         if (!buf) {
 260                 printk(KERN_ERR "Memory allocation error\n");
 261                 kfree(obj);
 262                 kfree(obj_list);
 263                 return NULL;
 264         }
 265
 266         acpi_set_pdc_bits(buf);
 267
 268         obj->type = ACPI_TYPE_BUFFER;
 269         obj->buffer.length = 12;
 270         obj->buffer.pointer = (u8 *) buf;
 271         obj_list->count = 1;
 272         obj_list->pointer = obj;
 273
 274         return obj_list;
 275 }
 276
 277 /*
 278  * _PDC is required for a BIOS-OS handshake for most of the newer
 279  * ACPI processor features.
 280  */
 281 static int
 282 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in)
 283 {
 284         acpi_status status = AE_OK;
 285
 286         if (idle_nomwait) {
 287                 /*
 288                  * If mwait is disabled for CPU C-states, the C2C3_FFH access
 289                  * mode will be disabled in the parameter of _PDC object.
 290                  * Of course C1_FFH access mode will also be disabled.
 291                  */
 292                 union acpi_object *obj;
 293                 u32 *buffer = NULL;
 294
 295                 obj = pdc_in->pointer;
 296                 buffer = (u32 *)(obj->buffer.pointer);
 297                 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH);
 298
 299         }
 300         status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL);
 301
 302         if (ACPI_FAILURE(status))
 303                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 304                     "Could not evaluate _PDC, using legacy perf. control.\n"));
 305
 306         return status;
 307 }
 308
 309 void acpi_processor_set_pdc(acpi_handle handle)
 310 {
 311         struct acpi_object_list *obj_list;
 312
 313         if (arch_has_acpi_pdc() == false)
 314                 return;
 315
 316         obj_list = acpi_processor_alloc_pdc();
 317         if (!obj_list)
 318                 return;
 319
 320         acpi_processor_eval_pdc(handle, obj_list);
 321
 322         kfree(obj_list->pointer->buffer.pointer);
 323         kfree(obj_list->pointer);
 324         kfree(obj_list);
 325 }
 326 EXPORT_SYMBOL_GPL(acpi_processor_set_pdc);
 327
 328 static acpi_status
 329 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
 330 {
 331         if (processor_physically_present(handle) == false)
 332                 return AE_OK;
 333
 334         acpi_processor_set_pdc(handle);
 335         return AE_OK;
 336 }
 337
 338 void __init acpi_early_processor_set_pdc(void)
 339 {
 340         /*
 341          * Check whether the system is DMI table. If yes, OSPM
 342          * should not use mwait for CPU-states.
 343          */
 344         dmi_check_system(processor_idle_dmi_table);
 345
 346         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 347                             ACPI_UINT32_MAX,
 348                             early_init_pdc, NULL, NULL, NULL);
 349         acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL);
 350 }