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