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