kernel/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(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 */