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 * 8 * I/O APIC hotplug support 9 * Yinghai Lu <yinghai@kernel.org> 10 * Jiang Liu <jiang.liu@intel.com> 11 */ 12 #include <linux/export.h> 13 #include <linux/acpi.h> 14 #include <acpi/processor.h> 15 16 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 17 ACPI_MODULE_NAME("processor_core"); 18 19 static struct acpi_table_madt *get_madt_table(void) 20 { 21 static struct acpi_table_madt *madt; 22 static int read_madt; 23 24 if (!read_madt) { 25 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, 26 (struct acpi_table_header **)&madt))) 27 madt = NULL; 28 read_madt++; 29 } 30 31 return madt; 32 } 33 34 static int map_lapic_id(struct acpi_subtable_header *entry, 35 u32 acpi_id, phys_cpuid_t *apic_id) 36 { 37 struct acpi_madt_local_apic *lapic = 38 container_of(entry, struct acpi_madt_local_apic, header); 39 40 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED)) 41 return -ENODEV; 42 43 if (lapic->processor_id != acpi_id) 44 return -EINVAL; 45 46 *apic_id = lapic->id; 47 return 0; 48 } 49 50 static int map_x2apic_id(struct acpi_subtable_header *entry, 51 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id) 52 { 53 struct acpi_madt_local_x2apic *apic = 54 container_of(entry, struct acpi_madt_local_x2apic, header); 55 56 if (!(apic->lapic_flags & ACPI_MADT_ENABLED)) 57 return -ENODEV; 58 59 if (device_declaration && (apic->uid == acpi_id)) { 60 *apic_id = apic->local_apic_id; 61 return 0; 62 } 63 64 return -EINVAL; 65 } 66 67 static int map_lsapic_id(struct acpi_subtable_header *entry, 68 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id) 69 { 70 struct acpi_madt_local_sapic *lsapic = 71 container_of(entry, struct acpi_madt_local_sapic, header); 72 73 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED)) 74 return -ENODEV; 75 76 if (device_declaration) { 77 if ((entry->length < 16) || (lsapic->uid != acpi_id)) 78 return -EINVAL; 79 } else if (lsapic->processor_id != acpi_id) 80 return -EINVAL; 81 82 *apic_id = (lsapic->id << 8) | lsapic->eid; 83 return 0; 84 } 85 86 /* 87 * Retrieve the ARM CPU physical identifier (MPIDR) 88 */ 89 static int map_gicc_mpidr(struct acpi_subtable_header *entry, 90 int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr) 91 { 92 struct acpi_madt_generic_interrupt *gicc = 93 container_of(entry, struct acpi_madt_generic_interrupt, header); 94 95 if (!(gicc->flags & ACPI_MADT_ENABLED)) 96 return -ENODEV; 97 98 /* device_declaration means Device object in DSDT, in the 99 * GIC interrupt model, logical processors are required to 100 * have a Processor Device object in the DSDT, so we should 101 * check device_declaration here 102 */ 103 if (device_declaration && (gicc->uid == acpi_id)) { 104 *mpidr = gicc->arm_mpidr; 105 return 0; 106 } 107 108 return -EINVAL; 109 } 110 111 static phys_cpuid_t map_madt_entry(int type, u32 acpi_id) 112 { 113 unsigned long madt_end, entry; 114 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */ 115 struct acpi_table_madt *madt; 116 117 madt = get_madt_table(); 118 if (!madt) 119 return phys_id; 120 121 entry = (unsigned long)madt; 122 madt_end = entry + madt->header.length; 123 124 /* Parse all entries looking for a match. */ 125 126 entry += sizeof(struct acpi_table_madt); 127 while (entry + sizeof(struct acpi_subtable_header) < madt_end) { 128 struct acpi_subtable_header *header = 129 (struct acpi_subtable_header *)entry; 130 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) { 131 if (!map_lapic_id(header, acpi_id, &phys_id)) 132 break; 133 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) { 134 if (!map_x2apic_id(header, type, acpi_id, &phys_id)) 135 break; 136 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) { 137 if (!map_lsapic_id(header, type, acpi_id, &phys_id)) 138 break; 139 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) { 140 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id)) 141 break; 142 } 143 entry += header->length; 144 } 145 return phys_id; 146 } 147 148 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id) 149 { 150 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 151 union acpi_object *obj; 152 struct acpi_subtable_header *header; 153 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; 154 155 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer))) 156 goto exit; 157 158 if (!buffer.length || !buffer.pointer) 159 goto exit; 160 161 obj = buffer.pointer; 162 if (obj->type != ACPI_TYPE_BUFFER || 163 obj->buffer.length < sizeof(struct acpi_subtable_header)) { 164 goto exit; 165 } 166 167 header = (struct acpi_subtable_header *)obj->buffer.pointer; 168 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) 169 map_lapic_id(header, acpi_id, &phys_id); 170 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) 171 map_lsapic_id(header, type, acpi_id, &phys_id); 172 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) 173 map_x2apic_id(header, type, acpi_id, &phys_id); 174 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) 175 map_gicc_mpidr(header, type, acpi_id, &phys_id); 176 177 exit: 178 kfree(buffer.pointer); 179 return phys_id; 180 } 181 182 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id) 183 { 184 phys_cpuid_t phys_id; 185 186 phys_id = map_mat_entry(handle, type, acpi_id); 187 if (phys_id == PHYS_CPUID_INVALID) 188 phys_id = map_madt_entry(type, acpi_id); 189 190 return phys_id; 191 } 192 193 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id) 194 { 195 #ifdef CONFIG_SMP 196 int i; 197 #endif 198 199 if (phys_id == PHYS_CPUID_INVALID) { 200 /* 201 * On UP processor, there is no _MAT or MADT table. 202 * So above phys_id is always set to PHYS_CPUID_INVALID. 203 * 204 * BIOS may define multiple CPU handles even for UP processor. 205 * For example, 206 * 207 * Scope (_PR) 208 * { 209 * Processor (CPU0, 0x00, 0x00000410, 0x06) {} 210 * Processor (CPU1, 0x01, 0x00000410, 0x06) {} 211 * Processor (CPU2, 0x02, 0x00000410, 0x06) {} 212 * Processor (CPU3, 0x03, 0x00000410, 0x06) {} 213 * } 214 * 215 * Ignores phys_id and always returns 0 for the processor 216 * handle with acpi id 0 if nr_cpu_ids is 1. 217 * This should be the case if SMP tables are not found. 218 * Return -1 for other CPU's handle. 219 */ 220 if (nr_cpu_ids <= 1 && acpi_id == 0) 221 return acpi_id; 222 else 223 return -1; 224 } 225 226 #ifdef CONFIG_SMP 227 for_each_possible_cpu(i) { 228 if (cpu_physical_id(i) == phys_id) 229 return i; 230 } 231 #else 232 /* In UP kernel, only processor 0 is valid */ 233 if (phys_id == 0) 234 return phys_id; 235 #endif 236 return -1; 237 } 238 239 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id) 240 { 241 phys_cpuid_t phys_id; 242 243 phys_id = acpi_get_phys_id(handle, type, acpi_id); 244 245 return acpi_map_cpuid(phys_id, acpi_id); 246 } 247 EXPORT_SYMBOL_GPL(acpi_get_cpuid); 248 249 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC 250 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base, 251 u64 *phys_addr, int *ioapic_id) 252 { 253 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry; 254 255 if (ioapic->global_irq_base != gsi_base) 256 return 0; 257 258 *phys_addr = ioapic->address; 259 *ioapic_id = ioapic->id; 260 return 1; 261 } 262 263 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr) 264 { 265 struct acpi_subtable_header *hdr; 266 unsigned long madt_end, entry; 267 struct acpi_table_madt *madt; 268 int apic_id = -1; 269 270 madt = get_madt_table(); 271 if (!madt) 272 return apic_id; 273 274 entry = (unsigned long)madt; 275 madt_end = entry + madt->header.length; 276 277 /* Parse all entries looking for a match. */ 278 entry += sizeof(struct acpi_table_madt); 279 while (entry + sizeof(struct acpi_subtable_header) < madt_end) { 280 hdr = (struct acpi_subtable_header *)entry; 281 if (hdr->type == ACPI_MADT_TYPE_IO_APIC && 282 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id)) 283 break; 284 else 285 entry += hdr->length; 286 } 287 288 return apic_id; 289 } 290 291 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base, 292 u64 *phys_addr) 293 { 294 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 295 struct acpi_subtable_header *header; 296 union acpi_object *obj; 297 int apic_id = -1; 298 299 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer))) 300 goto exit; 301 302 if (!buffer.length || !buffer.pointer) 303 goto exit; 304 305 obj = buffer.pointer; 306 if (obj->type != ACPI_TYPE_BUFFER || 307 obj->buffer.length < sizeof(struct acpi_subtable_header)) 308 goto exit; 309 310 header = (struct acpi_subtable_header *)obj->buffer.pointer; 311 if (header->type == ACPI_MADT_TYPE_IO_APIC) 312 get_ioapic_id(header, gsi_base, phys_addr, &apic_id); 313 314 exit: 315 kfree(buffer.pointer); 316 return apic_id; 317 } 318 319 /** 320 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base 321 * @handle: ACPI object for IOAPIC device 322 * @gsi_base: GSI base to match with 323 * @phys_addr: Pointer to store physical address of matching IOAPIC record 324 * 325 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search 326 * for an ACPI IOAPIC record matching @gsi_base. 327 * Return IOAPIC id and store physical address in @phys_addr if found a match, 328 * otherwise return <0. 329 */ 330 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr) 331 { 332 int apic_id; 333 334 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr); 335 if (apic_id == -1) 336 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr); 337 338 return apic_id; 339 } 340 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */ 341