drivers/acpi/processor_core.c

   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(struct acpi_table_madt *madt,
 112                                    int type, u32 acpi_id)
 113 {
 114         unsigned long madt_end, entry;
 115         phys_cpuid_t phys_id = PHYS_CPUID_INVALID;      /* CPU hardware ID */
 116
 117         if (!madt)
 118                 return phys_id;
 119
 120         entry = (unsigned long)madt;
 121         madt_end = entry + madt->header.length;
 122
 123         /* Parse all entries looking for a match. */
 124
 125         entry += sizeof(struct acpi_table_madt);
 126         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 127                 struct acpi_subtable_header *header =
 128                         (struct acpi_subtable_header *)entry;
 129                 if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
 130                         if (!map_lapic_id(header, acpi_id, &phys_id))
 131                                 break;
 132                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
 133                         if (!map_x2apic_id(header, type, acpi_id, &phys_id))
 134                                 break;
 135                 } else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
 136                         if (!map_lsapic_id(header, type, acpi_id, &phys_id))
 137                                 break;
 138                 } else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
 139                         if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
 140                                 break;
 141                 }
 142                 entry += header->length;
 143         }
 144         return phys_id;
 145 }
 146
 147 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
 148 {
 149         struct acpi_table_madt *madt = NULL;
 150         acpi_size tbl_size;
 151         phys_cpuid_t rv;
 152
 153         acpi_get_table_with_size(ACPI_SIG_MADT, 0,
 154                                  (struct acpi_table_header **)&madt,
 155                                  &tbl_size);
 156         if (!madt)
 157                 return PHYS_CPUID_INVALID;
 158
 159         rv = map_madt_entry(madt, 1, acpi_id);
 160
 161         early_acpi_os_unmap_memory(madt, tbl_size);
 162
 163         return rv;
 164 }
 165
 166 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
 167 {
 168         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 169         union acpi_object *obj;
 170         struct acpi_subtable_header *header;
 171         phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
 172
 173         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 174                 goto exit;
 175
 176         if (!buffer.length || !buffer.pointer)
 177                 goto exit;
 178
 179         obj = buffer.pointer;
 180         if (obj->type != ACPI_TYPE_BUFFER ||
 181             obj->buffer.length < sizeof(struct acpi_subtable_header)) {
 182                 goto exit;
 183         }
 184
 185         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 186         if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
 187                 map_lapic_id(header, acpi_id, &phys_id);
 188         else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
 189                 map_lsapic_id(header, type, acpi_id, &phys_id);
 190         else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
 191                 map_x2apic_id(header, type, acpi_id, &phys_id);
 192         else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
 193                 map_gicc_mpidr(header, type, acpi_id, &phys_id);
 194
 195 exit:
 196         kfree(buffer.pointer);
 197         return phys_id;
 198 }
 199
 200 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
 201 {
 202         phys_cpuid_t phys_id;
 203
 204         phys_id = map_mat_entry(handle, type, acpi_id);
 205         if (invalid_phys_cpuid(phys_id))
 206                 phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
 207
 208         return phys_id;
 209 }
 210
 211 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
 212 {
 213 #ifdef CONFIG_SMP
 214         int i;
 215 #endif
 216
 217         if (invalid_phys_cpuid(phys_id)) {
 218                 /*
 219                  * On UP processor, there is no _MAT or MADT table.
 220                  * So above phys_id is always set to PHYS_CPUID_INVALID.
 221                  *
 222                  * BIOS may define multiple CPU handles even for UP processor.
 223                  * For example,
 224                  *
 225                  * Scope (_PR)
 226                  * {
 227                  *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
 228                  *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
 229                  *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
 230                  *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
 231                  * }
 232                  *
 233                  * Ignores phys_id and always returns 0 for the processor
 234                  * handle with acpi id 0 if nr_cpu_ids is 1.
 235                  * This should be the case if SMP tables are not found.
 236                  * Return -EINVAL for other CPU's handle.
 237                  */
 238                 if (nr_cpu_ids <= 1 && acpi_id == 0)
 239                         return acpi_id;
 240                 else
 241                         return -EINVAL;
 242         }
 243
 244 #ifdef CONFIG_SMP
 245         for_each_possible_cpu(i) {
 246                 if (cpu_physical_id(i) == phys_id)
 247                         return i;
 248         }
 249 #else
 250         /* In UP kernel, only processor 0 is valid */
 251         if (phys_id == 0)
 252                 return phys_id;
 253 #endif
 254         return -ENODEV;
 255 }
 256
 257 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
 258 {
 259         phys_cpuid_t phys_id;
 260
 261         phys_id = acpi_get_phys_id(handle, type, acpi_id);
 262
 263         return acpi_map_cpuid(phys_id, acpi_id);
 264 }
 265 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
 266
 267 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
 268 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
 269                          u64 *phys_addr, int *ioapic_id)
 270 {
 271         struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
 272
 273         if (ioapic->global_irq_base != gsi_base)
 274                 return 0;
 275
 276         *phys_addr = ioapic->address;
 277         *ioapic_id = ioapic->id;
 278         return 1;
 279 }
 280
 281 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
 282 {
 283         struct acpi_subtable_header *hdr;
 284         unsigned long madt_end, entry;
 285         struct acpi_table_madt *madt;
 286         int apic_id = -1;
 287
 288         madt = get_madt_table();
 289         if (!madt)
 290                 return apic_id;
 291
 292         entry = (unsigned long)madt;
 293         madt_end = entry + madt->header.length;
 294
 295         /* Parse all entries looking for a match. */
 296         entry += sizeof(struct acpi_table_madt);
 297         while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
 298                 hdr = (struct acpi_subtable_header *)entry;
 299                 if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
 300                     get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
 301                         break;
 302                 else
 303                         entry += hdr->length;
 304         }
 305
 306         return apic_id;
 307 }
 308
 309 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
 310                                   u64 *phys_addr)
 311 {
 312         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 313         struct acpi_subtable_header *header;
 314         union acpi_object *obj;
 315         int apic_id = -1;
 316
 317         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 318                 goto exit;
 319
 320         if (!buffer.length || !buffer.pointer)
 321                 goto exit;
 322
 323         obj = buffer.pointer;
 324         if (obj->type != ACPI_TYPE_BUFFER ||
 325             obj->buffer.length < sizeof(struct acpi_subtable_header))
 326                 goto exit;
 327
 328         header = (struct acpi_subtable_header *)obj->buffer.pointer;
 329         if (header->type == ACPI_MADT_TYPE_IO_APIC)
 330                 get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
 331
 332 exit:
 333         kfree(buffer.pointer);
 334         return apic_id;
 335 }
 336
 337 /**
 338  * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
 339  * @handle:     ACPI object for IOAPIC device
 340  * @gsi_base:   GSI base to match with
 341  * @phys_addr:  Pointer to store physical address of matching IOAPIC record
 342  *
 343  * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
 344  * for an ACPI IOAPIC record matching @gsi_base.
 345  * Return IOAPIC id and store physical address in @phys_addr if found a match,
 346  * otherwise return <0.
 347  */
 348 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
 349 {
 350         int apic_id;
 351
 352         apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
 353         if (apic_id == -1)
 354                 apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
 355
 356         return apic_id;
 357 }
 358 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */