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 14 #include <acpi/acpi_drivers.h> 15 #include <acpi/processor.h> 16 17 #include "internal.h" 18 19 #define PREFIX "ACPI: " 20 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 21 ACPI_MODULE_NAME("processor_core"); 22 23 static int __init set_no_mwait(const struct dmi_system_id *id) 24 { 25 printk(KERN_NOTICE PREFIX "%s detected - " 26 "disabling mwait for CPU C-states\n", id->ident); 27 boot_option_idle_override = IDLE_NOMWAIT; 28 return 0; 29 } 30 31 static struct dmi_system_id processor_idle_dmi_table[] __initdata = { 32 { 33 set_no_mwait, "Extensa 5220", { 34 DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies LTD"), 35 DMI_MATCH(DMI_SYS_VENDOR, "Acer"), 36 DMI_MATCH(DMI_PRODUCT_VERSION, "0100"), 37 DMI_MATCH(DMI_BOARD_NAME, "Columbia") }, NULL}, 38 {}, 39 }; 40 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 kfree(buffer.pointer); 162 return apic_id; 163 } 164 165 int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id) 166 { 167 int apic_id; 168 169 apic_id = map_mat_entry(handle, type, acpi_id); 170 if (apic_id == -1) 171 apic_id = map_madt_entry(type, acpi_id); 172 173 return apic_id; 174 } 175 176 int acpi_map_cpuid(int apic_id, u32 acpi_id) 177 { 178 #ifdef CONFIG_SMP 179 int i; 180 #endif 181 182 if (apic_id == -1) { 183 /* 184 * On UP processor, there is no _MAT or MADT table. 185 * So above apic_id is always set to -1. 186 * 187 * BIOS may define multiple CPU handles even for UP processor. 188 * For example, 189 * 190 * Scope (_PR) 191 * { 192 * Processor (CPU0, 0x00, 0x00000410, 0x06) {} 193 * Processor (CPU1, 0x01, 0x00000410, 0x06) {} 194 * Processor (CPU2, 0x02, 0x00000410, 0x06) {} 195 * Processor (CPU3, 0x03, 0x00000410, 0x06) {} 196 * } 197 * 198 * Ignores apic_id and always returns 0 for the processor 199 * handle with acpi id 0 if nr_cpu_ids is 1. 200 * This should be the case if SMP tables are not found. 201 * Return -1 for other CPU's handle. 202 */ 203 if (nr_cpu_ids <= 1 && acpi_id == 0) 204 return acpi_id; 205 else 206 return apic_id; 207 } 208 209 #ifdef CONFIG_SMP 210 for_each_possible_cpu(i) { 211 if (cpu_physical_id(i) == apic_id) 212 return i; 213 } 214 #else 215 /* In UP kernel, only processor 0 is valid */ 216 if (apic_id == 0) 217 return apic_id; 218 #endif 219 return -1; 220 } 221 222 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id) 223 { 224 int apic_id; 225 226 apic_id = acpi_get_apicid(handle, type, acpi_id); 227 228 return acpi_map_cpuid(apic_id, acpi_id); 229 } 230 EXPORT_SYMBOL_GPL(acpi_get_cpuid); 231 232 static bool __init processor_physically_present(acpi_handle handle) 233 { 234 int cpuid, type; 235 u32 acpi_id; 236 acpi_status status; 237 acpi_object_type acpi_type; 238 unsigned long long tmp; 239 union acpi_object object = { 0 }; 240 struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; 241 242 status = acpi_get_type(handle, &acpi_type); 243 if (ACPI_FAILURE(status)) 244 return false; 245 246 switch (acpi_type) { 247 case ACPI_TYPE_PROCESSOR: 248 status = acpi_evaluate_object(handle, NULL, NULL, &buffer); 249 if (ACPI_FAILURE(status)) 250 return false; 251 acpi_id = object.processor.proc_id; 252 break; 253 case ACPI_TYPE_DEVICE: 254 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp); 255 if (ACPI_FAILURE(status)) 256 return false; 257 acpi_id = tmp; 258 break; 259 default: 260 return false; 261 } 262 263 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0; 264 cpuid = acpi_get_cpuid(handle, type, acpi_id); 265 266 if (cpuid == -1) 267 return false; 268 269 return true; 270 } 271 272 static void acpi_set_pdc_bits(u32 *buf) 273 { 274 buf[0] = ACPI_PDC_REVISION_ID; 275 buf[1] = 1; 276 277 /* Enable coordination with firmware's _TSD info */ 278 buf[2] = ACPI_PDC_SMP_T_SWCOORD; 279 280 /* Twiddle arch-specific bits needed for _PDC */ 281 arch_acpi_set_pdc_bits(buf); 282 } 283 284 static struct acpi_object_list *acpi_processor_alloc_pdc(void) 285 { 286 struct acpi_object_list *obj_list; 287 union acpi_object *obj; 288 u32 *buf; 289 290 /* allocate and initialize pdc. It will be used later. */ 291 obj_list = kmalloc(sizeof(struct acpi_object_list), GFP_KERNEL); 292 if (!obj_list) { 293 printk(KERN_ERR "Memory allocation error\n"); 294 return NULL; 295 } 296 297 obj = kmalloc(sizeof(union acpi_object), GFP_KERNEL); 298 if (!obj) { 299 printk(KERN_ERR "Memory allocation error\n"); 300 kfree(obj_list); 301 return NULL; 302 } 303 304 buf = kmalloc(12, GFP_KERNEL); 305 if (!buf) { 306 printk(KERN_ERR "Memory allocation error\n"); 307 kfree(obj); 308 kfree(obj_list); 309 return NULL; 310 } 311 312 acpi_set_pdc_bits(buf); 313 314 obj->type = ACPI_TYPE_BUFFER; 315 obj->buffer.length = 12; 316 obj->buffer.pointer = (u8 *) buf; 317 obj_list->count = 1; 318 obj_list->pointer = obj; 319 320 return obj_list; 321 } 322 323 /* 324 * _PDC is required for a BIOS-OS handshake for most of the newer 325 * ACPI processor features. 326 */ 327 static int 328 acpi_processor_eval_pdc(acpi_handle handle, struct acpi_object_list *pdc_in) 329 { 330 acpi_status status = AE_OK; 331 332 if (boot_option_idle_override == IDLE_NOMWAIT) { 333 /* 334 * If mwait is disabled for CPU C-states, the C2C3_FFH access 335 * mode will be disabled in the parameter of _PDC object. 336 * Of course C1_FFH access mode will also be disabled. 337 */ 338 union acpi_object *obj; 339 u32 *buffer = NULL; 340 341 obj = pdc_in->pointer; 342 buffer = (u32 *)(obj->buffer.pointer); 343 buffer[2] &= ~(ACPI_PDC_C_C2C3_FFH | ACPI_PDC_C_C1_FFH); 344 345 } 346 status = acpi_evaluate_object(handle, "_PDC", pdc_in, NULL); 347 348 if (ACPI_FAILURE(status)) 349 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 350 "Could not evaluate _PDC, using legacy perf. control.\n")); 351 352 return status; 353 } 354 355 void acpi_processor_set_pdc(acpi_handle handle) 356 { 357 struct acpi_object_list *obj_list; 358 359 if (arch_has_acpi_pdc() == false) 360 return; 361 362 obj_list = acpi_processor_alloc_pdc(); 363 if (!obj_list) 364 return; 365 366 acpi_processor_eval_pdc(handle, obj_list); 367 368 kfree(obj_list->pointer->buffer.pointer); 369 kfree(obj_list->pointer); 370 kfree(obj_list); 371 } 372 373 static acpi_status __init 374 early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv) 375 { 376 if (processor_physically_present(handle) == false) 377 return AE_OK; 378 379 acpi_processor_set_pdc(handle); 380 return AE_OK; 381 } 382 383 void __init acpi_early_processor_set_pdc(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 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, 392 ACPI_UINT32_MAX, 393 early_init_pdc, NULL, NULL, NULL); 394 acpi_get_devices("ACPI0007", early_init_pdc, NULL, NULL); 395 } 396