1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2005 Intel Corporation 4 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. 5 * 6 * Alex Chiang <achiang@hp.com> 7 * - Unified x86/ia64 implementations 8 * 9 * I/O APIC hotplug support 10 * Yinghai Lu <yinghai@kernel.org> 11 * Jiang Liu <jiang.liu@intel.com> 12 */ 13 #include <linux/export.h> 14 #include <linux/acpi.h> 15 #include <acpi/processor.h> 16 17 static struct acpi_table_madt *get_madt_table(void) 18 { 19 static struct acpi_table_madt *madt; 20 static int read_madt; 21 22 if (!read_madt) { 23 if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0, 24 (struct acpi_table_header **)&madt))) 25 madt = NULL; 26 read_madt++; 27 } 28 29 return madt; 30 } 31 32 static int map_lapic_id(struct acpi_subtable_header *entry, 33 u32 acpi_id, phys_cpuid_t *apic_id) 34 { 35 struct acpi_madt_local_apic *lapic = 36 container_of(entry, struct acpi_madt_local_apic, header); 37 38 if (!(lapic->lapic_flags & ACPI_MADT_ENABLED)) 39 return -ENODEV; 40 41 if (lapic->processor_id != acpi_id) 42 return -EINVAL; 43 44 *apic_id = lapic->id; 45 return 0; 46 } 47 48 static int map_x2apic_id(struct acpi_subtable_header *entry, 49 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id) 50 { 51 struct acpi_madt_local_x2apic *apic = 52 container_of(entry, struct acpi_madt_local_x2apic, header); 53 54 if (!(apic->lapic_flags & ACPI_MADT_ENABLED)) 55 return -ENODEV; 56 57 if (device_declaration && (apic->uid == acpi_id)) { 58 *apic_id = apic->local_apic_id; 59 return 0; 60 } 61 62 return -EINVAL; 63 } 64 65 static int map_lsapic_id(struct acpi_subtable_header *entry, 66 int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id) 67 { 68 struct acpi_madt_local_sapic *lsapic = 69 container_of(entry, struct acpi_madt_local_sapic, header); 70 71 if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED)) 72 return -ENODEV; 73 74 if (device_declaration) { 75 if ((entry->length < 16) || (lsapic->uid != acpi_id)) 76 return -EINVAL; 77 } else if (lsapic->processor_id != acpi_id) 78 return -EINVAL; 79 80 *apic_id = (lsapic->id << 8) | lsapic->eid; 81 return 0; 82 } 83 84 /* 85 * Retrieve the ARM CPU physical identifier (MPIDR) 86 */ 87 static int map_gicc_mpidr(struct acpi_subtable_header *entry, 88 int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr) 89 { 90 struct acpi_madt_generic_interrupt *gicc = 91 container_of(entry, struct acpi_madt_generic_interrupt, header); 92 93 if (!(gicc->flags & ACPI_MADT_ENABLED)) 94 return -ENODEV; 95 96 /* device_declaration means Device object in DSDT, in the 97 * GIC interrupt model, logical processors are required to 98 * have a Processor Device object in the DSDT, so we should 99 * check device_declaration here 100 */ 101 if (device_declaration && (gicc->uid == acpi_id)) { 102 *mpidr = gicc->arm_mpidr; 103 return 0; 104 } 105 106 return -EINVAL; 107 } 108 109 static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt, 110 int type, u32 acpi_id) 111 { 112 unsigned long madt_end, entry; 113 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; /* CPU hardware ID */ 114 115 if (!madt) 116 return phys_id; 117 118 entry = (unsigned long)madt; 119 madt_end = entry + madt->header.length; 120 121 /* Parse all entries looking for a match. */ 122 123 entry += sizeof(struct acpi_table_madt); 124 while (entry + sizeof(struct acpi_subtable_header) < madt_end) { 125 struct acpi_subtable_header *header = 126 (struct acpi_subtable_header *)entry; 127 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) { 128 if (!map_lapic_id(header, acpi_id, &phys_id)) 129 break; 130 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) { 131 if (!map_x2apic_id(header, type, acpi_id, &phys_id)) 132 break; 133 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) { 134 if (!map_lsapic_id(header, type, acpi_id, &phys_id)) 135 break; 136 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) { 137 if (!map_gicc_mpidr(header, type, acpi_id, &phys_id)) 138 break; 139 } 140 entry += header->length; 141 } 142 return phys_id; 143 } 144 145 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id) 146 { 147 struct acpi_table_madt *madt = NULL; 148 phys_cpuid_t rv; 149 150 acpi_get_table(ACPI_SIG_MADT, 0, 151 (struct acpi_table_header **)&madt); 152 if (!madt) 153 return PHYS_CPUID_INVALID; 154 155 rv = map_madt_entry(madt, 1, acpi_id); 156 157 acpi_put_table((struct acpi_table_header *)madt); 158 159 return rv; 160 } 161 162 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id) 163 { 164 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 165 union acpi_object *obj; 166 struct acpi_subtable_header *header; 167 phys_cpuid_t phys_id = PHYS_CPUID_INVALID; 168 169 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer))) 170 goto exit; 171 172 if (!buffer.length || !buffer.pointer) 173 goto exit; 174 175 obj = buffer.pointer; 176 if (obj->type != ACPI_TYPE_BUFFER || 177 obj->buffer.length < sizeof(struct acpi_subtable_header)) { 178 goto exit; 179 } 180 181 header = (struct acpi_subtable_header *)obj->buffer.pointer; 182 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) 183 map_lapic_id(header, acpi_id, &phys_id); 184 else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) 185 map_lsapic_id(header, type, acpi_id, &phys_id); 186 else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) 187 map_x2apic_id(header, type, acpi_id, &phys_id); 188 else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) 189 map_gicc_mpidr(header, type, acpi_id, &phys_id); 190 191 exit: 192 kfree(buffer.pointer); 193 return phys_id; 194 } 195 196 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id) 197 { 198 phys_cpuid_t phys_id; 199 200 phys_id = map_mat_entry(handle, type, acpi_id); 201 if (invalid_phys_cpuid(phys_id)) 202 phys_id = map_madt_entry(get_madt_table(), type, acpi_id); 203 204 return phys_id; 205 } 206 EXPORT_SYMBOL_GPL(acpi_get_phys_id); 207 208 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id) 209 { 210 #ifdef CONFIG_SMP 211 int i; 212 #endif 213 214 if (invalid_phys_cpuid(phys_id)) { 215 /* 216 * On UP processor, there is no _MAT or MADT table. 217 * So above phys_id is always set to PHYS_CPUID_INVALID. 218 * 219 * BIOS may define multiple CPU handles even for UP processor. 220 * For example, 221 * 222 * Scope (_PR) 223 * { 224 * Processor (CPU0, 0x00, 0x00000410, 0x06) {} 225 * Processor (CPU1, 0x01, 0x00000410, 0x06) {} 226 * Processor (CPU2, 0x02, 0x00000410, 0x06) {} 227 * Processor (CPU3, 0x03, 0x00000410, 0x06) {} 228 * } 229 * 230 * Ignores phys_id and always returns 0 for the processor 231 * handle with acpi id 0 if nr_cpu_ids is 1. 232 * This should be the case if SMP tables are not found. 233 * Return -EINVAL for other CPU's handle. 234 */ 235 if (nr_cpu_ids <= 1 && acpi_id == 0) 236 return acpi_id; 237 else 238 return -EINVAL; 239 } 240 241 #ifdef CONFIG_SMP 242 for_each_possible_cpu(i) { 243 if (cpu_physical_id(i) == phys_id) 244 return i; 245 } 246 #else 247 /* In UP kernel, only processor 0 is valid */ 248 if (phys_id == 0) 249 return phys_id; 250 #endif 251 return -ENODEV; 252 } 253 254 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id) 255 { 256 phys_cpuid_t phys_id; 257 258 phys_id = acpi_get_phys_id(handle, type, acpi_id); 259 260 return acpi_map_cpuid(phys_id, acpi_id); 261 } 262 EXPORT_SYMBOL_GPL(acpi_get_cpuid); 263 264 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC 265 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base, 266 u64 *phys_addr, int *ioapic_id) 267 { 268 struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry; 269 270 if (ioapic->global_irq_base != gsi_base) 271 return 0; 272 273 *phys_addr = ioapic->address; 274 *ioapic_id = ioapic->id; 275 return 1; 276 } 277 278 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr) 279 { 280 struct acpi_subtable_header *hdr; 281 unsigned long madt_end, entry; 282 struct acpi_table_madt *madt; 283 int apic_id = -1; 284 285 madt = get_madt_table(); 286 if (!madt) 287 return apic_id; 288 289 entry = (unsigned long)madt; 290 madt_end = entry + madt->header.length; 291 292 /* Parse all entries looking for a match. */ 293 entry += sizeof(struct acpi_table_madt); 294 while (entry + sizeof(struct acpi_subtable_header) < madt_end) { 295 hdr = (struct acpi_subtable_header *)entry; 296 if (hdr->type == ACPI_MADT_TYPE_IO_APIC && 297 get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id)) 298 break; 299 else 300 entry += hdr->length; 301 } 302 303 return apic_id; 304 } 305 306 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base, 307 u64 *phys_addr) 308 { 309 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 310 struct acpi_subtable_header *header; 311 union acpi_object *obj; 312 int apic_id = -1; 313 314 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer))) 315 goto exit; 316 317 if (!buffer.length || !buffer.pointer) 318 goto exit; 319 320 obj = buffer.pointer; 321 if (obj->type != ACPI_TYPE_BUFFER || 322 obj->buffer.length < sizeof(struct acpi_subtable_header)) 323 goto exit; 324 325 header = (struct acpi_subtable_header *)obj->buffer.pointer; 326 if (header->type == ACPI_MADT_TYPE_IO_APIC) 327 get_ioapic_id(header, gsi_base, phys_addr, &apic_id); 328 329 exit: 330 kfree(buffer.pointer); 331 return apic_id; 332 } 333 334 /** 335 * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base 336 * @handle: ACPI object for IOAPIC device 337 * @gsi_base: GSI base to match with 338 * @phys_addr: Pointer to store physical address of matching IOAPIC record 339 * 340 * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search 341 * for an ACPI IOAPIC record matching @gsi_base. 342 * Return IOAPIC id and store physical address in @phys_addr if found a match, 343 * otherwise return <0. 344 */ 345 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr) 346 { 347 int apic_id; 348 349 apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr); 350 if (apic_id == -1) 351 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr); 352 353 return apic_id; 354 } 355 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */ 356