hw/acpi/nvdimm.c

   1 /*
   2  * NVDIMM ACPI Implementation
   3  *
   4  * Copyright(C) 2015 Intel Corporation.
   5  *
   6  * Author:
   7  *  Xiao Guangrong <guangrong.xiao@linux.intel.com>
   8  *
   9  * NFIT is defined in ACPI 6.0: 5.2.25 NVDIMM Firmware Interface Table (NFIT)
  10  * and the DSM specification can be found at:
  11  *       http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf
  12  *
  13  * Currently, it only supports PMEM Virtualization.
  14  *
  15  * This library is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU Lesser General Public
  17  * License as published by the Free Software Foundation; either
  18  * version 2 of the License, or (at your option) any later version.
  19  *
  20  * This library is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  23  * Lesser General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU Lesser General Public
  26  * License along with this library; if not, see <http://www.gnu.org/licenses/>
  27  */
  28
  29 #include "qemu/osdep.h"
  30 #include "hw/acpi/acpi.h"
  31 #include "hw/acpi/aml-build.h"
  32 #include "hw/acpi/bios-linker-loader.h"
  33 #include "hw/nvram/fw_cfg.h"
  34 #include "hw/mem/nvdimm.h"
  35
  36 static int nvdimm_plugged_device_list(Object *obj, void *opaque)
  37 {
  38     GSList **list = opaque;
  39
  40     if (object_dynamic_cast(obj, TYPE_NVDIMM)) {
  41         DeviceState *dev = DEVICE(obj);
  42
  43         if (dev->realized) { /* only realized NVDIMMs matter */
  44             *list = g_slist_append(*list, DEVICE(obj));
  45         }
  46     }
  47
  48     object_child_foreach(obj, nvdimm_plugged_device_list, opaque);
  49     return 0;
  50 }
  51
  52 /*
  53  * inquire plugged NVDIMM devices and link them into the list which is
  54  * returned to the caller.
  55  *
  56  * Note: it is the caller's responsibility to free the list to avoid
  57  * memory leak.
  58  */
  59 static GSList *nvdimm_get_plugged_device_list(void)
  60 {
  61     GSList *list = NULL;
  62
  63     object_child_foreach(qdev_get_machine(), nvdimm_plugged_device_list,
  64                          &list);
  65     return list;
  66 }
  67
  68 #define NVDIMM_UUID_LE(a, b, c, d0, d1, d2, d3, d4, d5, d6, d7)             \
  69    { (a) & 0xff, ((a) >> 8) & 0xff, ((a) >> 16) & 0xff, ((a) >> 24) & 0xff, \
  70      (b) & 0xff, ((b) >> 8) & 0xff, (c) & 0xff, ((c) >> 8) & 0xff,          \
  71      (d0), (d1), (d2), (d3), (d4), (d5), (d6), (d7) }
  72
  73 /*
  74  * define Byte Addressable Persistent Memory (PM) Region according to
  75  * ACPI 6.0: 5.2.25.1 System Physical Address Range Structure.
  76  */
  77 static const uint8_t nvdimm_nfit_spa_uuid[] =
  78       NVDIMM_UUID_LE(0x66f0d379, 0xb4f3, 0x4074, 0xac, 0x43, 0x0d, 0x33,
  79                      0x18, 0xb7, 0x8c, 0xdb);
  80
  81 /*
  82  * NVDIMM Firmware Interface Table
  83  * @signature: "NFIT"
  84  *
  85  * It provides information that allows OSPM to enumerate NVDIMM present in
  86  * the platform and associate system physical address ranges created by the
  87  * NVDIMMs.
  88  *
  89  * It is defined in ACPI 6.0: 5.2.25 NVDIMM Firmware Interface Table (NFIT)
  90  */
  91 struct NvdimmNfitHeader {
  92     ACPI_TABLE_HEADER_DEF
  93     uint32_t reserved;
  94 } QEMU_PACKED;
  95 typedef struct NvdimmNfitHeader NvdimmNfitHeader;
  96
  97 /*
  98  * define NFIT structures according to ACPI 6.0: 5.2.25 NVDIMM Firmware
  99  * Interface Table (NFIT).
 100  */
 101
 102 /*
 103  * System Physical Address Range Structure
 104  *
 105  * It describes the system physical address ranges occupied by NVDIMMs and
 106  * the types of the regions.
 107  */
 108 struct NvdimmNfitSpa {
 109     uint16_t type;
 110     uint16_t length;
 111     uint16_t spa_index;
 112     uint16_t flags;
 113     uint32_t reserved;
 114     uint32_t proximity_domain;
 115     uint8_t type_guid[16];
 116     uint64_t spa_base;
 117     uint64_t spa_length;
 118     uint64_t mem_attr;
 119 } QEMU_PACKED;
 120 typedef struct NvdimmNfitSpa NvdimmNfitSpa;
 121
 122 /*
 123  * Memory Device to System Physical Address Range Mapping Structure
 124  *
 125  * It enables identifying each NVDIMM region and the corresponding SPA
 126  * describing the memory interleave
 127  */
 128 struct NvdimmNfitMemDev {
 129     uint16_t type;
 130     uint16_t length;
 131     uint32_t nfit_handle;
 132     uint16_t phys_id;
 133     uint16_t region_id;
 134     uint16_t spa_index;
 135     uint16_t dcr_index;
 136     uint64_t region_len;
 137     uint64_t region_offset;
 138     uint64_t region_dpa;
 139     uint16_t interleave_index;
 140     uint16_t interleave_ways;
 141     uint16_t flags;
 142     uint16_t reserved;
 143 } QEMU_PACKED;
 144 typedef struct NvdimmNfitMemDev NvdimmNfitMemDev;
 145
 146 /*
 147  * NVDIMM Control Region Structure
 148  *
 149  * It describes the NVDIMM and if applicable, Block Control Window.
 150  */
 151 struct NvdimmNfitControlRegion {
 152     uint16_t type;
 153     uint16_t length;
 154     uint16_t dcr_index;
 155     uint16_t vendor_id;
 156     uint16_t device_id;
 157     uint16_t revision_id;
 158     uint16_t sub_vendor_id;
 159     uint16_t sub_device_id;
 160     uint16_t sub_revision_id;
 161     uint8_t reserved[6];
 162     uint32_t serial_number;
 163     uint16_t fic;
 164     uint16_t num_bcw;
 165     uint64_t bcw_size;
 166     uint64_t cmd_offset;
 167     uint64_t cmd_size;
 168     uint64_t status_offset;
 169     uint64_t status_size;
 170     uint16_t flags;
 171     uint8_t reserved2[6];
 172 } QEMU_PACKED;
 173 typedef struct NvdimmNfitControlRegion NvdimmNfitControlRegion;
 174
 175 /*
 176  * Module serial number is a unique number for each device. We use the
 177  * slot id of NVDIMM device to generate this number so that each device
 178  * associates with a different number.
 179  *
 180  * 0x123456 is a magic number we arbitrarily chose.
 181  */
 182 static uint32_t nvdimm_slot_to_sn(int slot)
 183 {
 184     return 0x123456 + slot;
 185 }
 186
 187 /*
 188  * handle is used to uniquely associate nfit_memdev structure with NVDIMM
 189  * ACPI device - nfit_memdev.nfit_handle matches with the value returned
 190  * by ACPI device _ADR method.
 191  *
 192  * We generate the handle with the slot id of NVDIMM device and reserve
 193  * 0 for NVDIMM root device.
 194  */
 195 static uint32_t nvdimm_slot_to_handle(int slot)
 196 {
 197     return slot + 1;
 198 }
 199
 200 /*
 201  * index uniquely identifies the structure, 0 is reserved which indicates
 202  * that the structure is not valid or the associated structure is not
 203  * present.
 204  *
 205  * Each NVDIMM device needs two indexes, one for nfit_spa and another for
 206  * nfit_dc which are generated by the slot id of NVDIMM device.
 207  */
 208 static uint16_t nvdimm_slot_to_spa_index(int slot)
 209 {
 210     return (slot + 1) << 1;
 211 }
 212
 213 /* See the comments of nvdimm_slot_to_spa_index(). */
 214 static uint32_t nvdimm_slot_to_dcr_index(int slot)
 215 {
 216     return nvdimm_slot_to_spa_index(slot) + 1;
 217 }
 218
 219 /* ACPI 6.0: 5.2.25.1 System Physical Address Range Structure */
 220 static void
 221 nvdimm_build_structure_spa(GArray *structures, DeviceState *dev)
 222 {
 223     NvdimmNfitSpa *nfit_spa;
 224     uint64_t addr = object_property_get_int(OBJECT(dev), PC_DIMM_ADDR_PROP,
 225                                             NULL);
 226     uint64_t size = object_property_get_int(OBJECT(dev), PC_DIMM_SIZE_PROP,
 227                                             NULL);
 228     uint32_t node = object_property_get_int(OBJECT(dev), PC_DIMM_NODE_PROP,
 229                                             NULL);
 230     int slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
 231                                             NULL);
 232
 233     nfit_spa = acpi_data_push(structures, sizeof(*nfit_spa));
 234
 235     nfit_spa->type = cpu_to_le16(0 /* System Physical Address Range
 236                                       Structure */);
 237     nfit_spa->length = cpu_to_le16(sizeof(*nfit_spa));
 238     nfit_spa->spa_index = cpu_to_le16(nvdimm_slot_to_spa_index(slot));
 239
 240     /*
 241      * Control region is strict as all the device info, such as SN, index,
 242      * is associated with slot id.
 243      */
 244     nfit_spa->flags = cpu_to_le16(1 /* Control region is strictly for
 245                                        management during hot add/online
 246                                        operation */ |
 247                                   2 /* Data in Proximity Domain field is
 248                                        valid*/);
 249
 250     /* NUMA node. */
 251     nfit_spa->proximity_domain = cpu_to_le32(node);
 252     /* the region reported as PMEM. */
 253     memcpy(nfit_spa->type_guid, nvdimm_nfit_spa_uuid,
 254            sizeof(nvdimm_nfit_spa_uuid));
 255
 256     nfit_spa->spa_base = cpu_to_le64(addr);
 257     nfit_spa->spa_length = cpu_to_le64(size);
 258
 259     /* It is the PMEM and can be cached as writeback. */
 260     nfit_spa->mem_attr = cpu_to_le64(0x8ULL /* EFI_MEMORY_WB */ |
 261                                      0x8000ULL /* EFI_MEMORY_NV */);
 262 }
 263
 264 /*
 265  * ACPI 6.0: 5.2.25.2 Memory Device to System Physical Address Range Mapping
 266  * Structure
 267  */
 268 static void
 269 nvdimm_build_structure_memdev(GArray *structures, DeviceState *dev)
 270 {
 271     NvdimmNfitMemDev *nfit_memdev;
 272     uint64_t addr = object_property_get_int(OBJECT(dev), PC_DIMM_ADDR_PROP,
 273                                             NULL);
 274     uint64_t size = object_property_get_int(OBJECT(dev), PC_DIMM_SIZE_PROP,
 275                                             NULL);
 276     int slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
 277                                             NULL);
 278     uint32_t handle = nvdimm_slot_to_handle(slot);
 279
 280     nfit_memdev = acpi_data_push(structures, sizeof(*nfit_memdev));
 281
 282     nfit_memdev->type = cpu_to_le16(1 /* Memory Device to System Address
 283                                          Range Map Structure*/);
 284     nfit_memdev->length = cpu_to_le16(sizeof(*nfit_memdev));
 285     nfit_memdev->nfit_handle = cpu_to_le32(handle);
 286
 287     /*
 288      * associate memory device with System Physical Address Range
 289      * Structure.
 290      */
 291     nfit_memdev->spa_index = cpu_to_le16(nvdimm_slot_to_spa_index(slot));
 292     /* associate memory device with Control Region Structure. */
 293     nfit_memdev->dcr_index = cpu_to_le16(nvdimm_slot_to_dcr_index(slot));
 294
 295     /* The memory region on the device. */
 296     nfit_memdev->region_len = cpu_to_le64(size);
 297     nfit_memdev->region_dpa = cpu_to_le64(addr);
 298
 299     /* Only one interleave for PMEM. */
 300     nfit_memdev->interleave_ways = cpu_to_le16(1);
 301 }
 302
 303 /*
 304  * ACPI 6.0: 5.2.25.5 NVDIMM Control Region Structure.
 305  */
 306 static void nvdimm_build_structure_dcr(GArray *structures, DeviceState *dev)
 307 {
 308     NvdimmNfitControlRegion *nfit_dcr;
 309     int slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
 310                                        NULL);
 311     uint32_t sn = nvdimm_slot_to_sn(slot);
 312
 313     nfit_dcr = acpi_data_push(structures, sizeof(*nfit_dcr));
 314
 315     nfit_dcr->type = cpu_to_le16(4 /* NVDIMM Control Region Structure */);
 316     nfit_dcr->length = cpu_to_le16(sizeof(*nfit_dcr));
 317     nfit_dcr->dcr_index = cpu_to_le16(nvdimm_slot_to_dcr_index(slot));
 318
 319     /* vendor: Intel. */
 320     nfit_dcr->vendor_id = cpu_to_le16(0x8086);
 321     nfit_dcr->device_id = cpu_to_le16(1);
 322
 323     /* The _DSM method is following Intel's DSM specification. */
 324     nfit_dcr->revision_id = cpu_to_le16(1 /* Current Revision supported
 325                                              in ACPI 6.0 is 1. */);
 326     nfit_dcr->serial_number = cpu_to_le32(sn);
 327     nfit_dcr->fic = cpu_to_le16(0x201 /* Format Interface Code. See Chapter
 328                                          2: NVDIMM Device Specific Method
 329                                          (DSM) in DSM Spec Rev1.*/);
 330 }
 331
 332 static GArray *nvdimm_build_device_structure(GSList *device_list)
 333 {
 334     GArray *structures = g_array_new(false, true /* clear */, 1);
 335
 336     for (; device_list; device_list = device_list->next) {
 337         DeviceState *dev = device_list->data;
 338
 339         /* build System Physical Address Range Structure. */
 340         nvdimm_build_structure_spa(structures, dev);
 341
 342         /*
 343          * build Memory Device to System Physical Address Range Mapping
 344          * Structure.
 345          */
 346         nvdimm_build_structure_memdev(structures, dev);
 347
 348         /* build NVDIMM Control Region Structure. */
 349         nvdimm_build_structure_dcr(structures, dev);
 350     }
 351
 352     return structures;
 353 }
 354
 355 static void nvdimm_build_nfit(GSList *device_list, GArray *table_offsets,
 356                               GArray *table_data, GArray *linker)
 357 {
 358     GArray *structures = nvdimm_build_device_structure(device_list);
 359     unsigned int header;
 360
 361     acpi_add_table(table_offsets, table_data);
 362
 363     /* NFIT header. */
 364     header = table_data->len;
 365     acpi_data_push(table_data, sizeof(NvdimmNfitHeader));
 366     /* NVDIMM device structures. */
 367     g_array_append_vals(table_data, structures->data, structures->len);
 368
 369     build_header(linker, table_data,
 370                  (void *)(table_data->data + header), "NFIT",
 371                  sizeof(NvdimmNfitHeader) + structures->len, 1, NULL, NULL);
 372     g_array_free(structures, true);
 373 }
 374
 375 struct NvdimmDsmIn {
 376     uint32_t handle;
 377     uint32_t revision;
 378     uint32_t function;
 379     /* the remaining size in the page is used by arg3. */
 380     union {
 381         uint8_t arg3[0];
 382     };
 383 } QEMU_PACKED;
 384 typedef struct NvdimmDsmIn NvdimmDsmIn;
 385
 386 struct NvdimmDsmOut {
 387     /* the size of buffer filled by QEMU. */
 388     uint32_t len;
 389     uint8_t data[0];
 390 } QEMU_PACKED;
 391 typedef struct NvdimmDsmOut NvdimmDsmOut;
 392
 393 struct NvdimmDsmFunc0Out {
 394     /* the size of buffer filled by QEMU. */
 395      uint32_t len;
 396      uint32_t supported_func;
 397 } QEMU_PACKED;
 398 typedef struct NvdimmDsmFunc0Out NvdimmDsmFunc0Out;
 399
 400 struct NvdimmDsmFuncNoPayloadOut {
 401     /* the size of buffer filled by QEMU. */
 402      uint32_t len;
 403      uint32_t func_ret_status;
 404 } QEMU_PACKED;
 405 typedef struct NvdimmDsmFuncNoPayloadOut NvdimmDsmFuncNoPayloadOut;
 406
 407 static uint64_t
 408 nvdimm_dsm_read(void *opaque, hwaddr addr, unsigned size)
 409 {
 410     nvdimm_debug("BUG: we never read _DSM IO Port.\n");
 411     return 0;
 412 }
 413
 414 static void
 415 nvdimm_dsm_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
 416 {
 417     NvdimmDsmIn *in;
 418     hwaddr dsm_mem_addr = val;
 419
 420     nvdimm_debug("dsm memory address %#" HWADDR_PRIx ".\n", dsm_mem_addr);
 421
 422     /*
 423      * The DSM memory is mapped to guest address space so an evil guest
 424      * can change its content while we are doing DSM emulation. Avoid
 425      * this by copying DSM memory to QEMU local memory.
 426      */
 427     in = g_malloc(TARGET_PAGE_SIZE);
 428     cpu_physical_memory_read(dsm_mem_addr, in, TARGET_PAGE_SIZE);
 429
 430     le32_to_cpus(&in->revision);
 431     le32_to_cpus(&in->function);
 432     le32_to_cpus(&in->handle);
 433
 434     nvdimm_debug("Revision %#x Handler %#x Function %#x.\n", in->revision,
 435                  in->handle, in->function);
 436
 437     /*
 438      * function 0 is called to inquire which functions are supported by
 439      * OSPM
 440      */
 441     if (in->function == 0) {
 442         NvdimmDsmFunc0Out func0 = {
 443             .len = cpu_to_le32(sizeof(func0)),
 444              /* No function supported other than function 0 */
 445             .supported_func = cpu_to_le32(0),
 446         };
 447         cpu_physical_memory_write(dsm_mem_addr, &func0, sizeof func0);
 448     } else {
 449         /* No function except function 0 is supported yet. */
 450         NvdimmDsmFuncNoPayloadOut out = {
 451             .len = cpu_to_le32(sizeof(out)),
 452             .func_ret_status = cpu_to_le32(1)  /* Not Supported */,
 453         };
 454         cpu_physical_memory_write(dsm_mem_addr, &out, sizeof(out));
 455     }
 456
 457     g_free(in);
 458 }
 459
 460 static const MemoryRegionOps nvdimm_dsm_ops = {
 461     .read = nvdimm_dsm_read,
 462     .write = nvdimm_dsm_write,
 463     .endianness = DEVICE_LITTLE_ENDIAN,
 464     .valid = {
 465         .min_access_size = 4,
 466         .max_access_size = 4,
 467     },
 468 };
 469
 470 void nvdimm_init_acpi_state(AcpiNVDIMMState *state, MemoryRegion *io,
 471                             FWCfgState *fw_cfg, Object *owner)
 472 {
 473     memory_region_init_io(&state->io_mr, owner, &nvdimm_dsm_ops, state,
 474                           "nvdimm-acpi-io", NVDIMM_ACPI_IO_LEN);
 475     memory_region_add_subregion(io, NVDIMM_ACPI_IO_BASE, &state->io_mr);
 476
 477     state->dsm_mem = g_array_new(false, true /* clear */, 1);
 478     acpi_data_push(state->dsm_mem, TARGET_PAGE_SIZE);
 479     fw_cfg_add_file(fw_cfg, NVDIMM_DSM_MEM_FILE, state->dsm_mem->data,
 480                     state->dsm_mem->len);
 481 }
 482
 483 #define NVDIMM_COMMON_DSM      "NCAL"
 484 #define NVDIMM_ACPI_MEM_ADDR   "MEMA"
 485
 486 static void nvdimm_build_common_dsm(Aml *dev)
 487 {
 488     Aml *method, *ifctx, *function, *dsm_mem, *unpatched, *result_size;
 489     uint8_t byte_list[1];
 490
 491     method = aml_method(NVDIMM_COMMON_DSM, 4, AML_SERIALIZED);
 492     function = aml_arg(2);
 493     dsm_mem = aml_name(NVDIMM_ACPI_MEM_ADDR);
 494
 495     /*
 496      * do not support any method if DSM memory address has not been
 497      * patched.
 498      */
 499     unpatched = aml_if(aml_equal(dsm_mem, aml_int(0x0)));
 500
 501     /*
 502      * function 0 is called to inquire what functions are supported by
 503      * OSPM
 504      */
 505     ifctx = aml_if(aml_equal(function, aml_int(0)));
 506     byte_list[0] = 0 /* No function Supported */;
 507     aml_append(ifctx, aml_return(aml_buffer(1, byte_list)));
 508     aml_append(unpatched, ifctx);
 509
 510     /* No function is supported yet. */
 511     byte_list[0] = 1 /* Not Supported */;
 512     aml_append(unpatched, aml_return(aml_buffer(1, byte_list)));
 513     aml_append(method, unpatched);
 514
 515     /*
 516      * The HDLE indicates the DSM function is issued from which device,
 517      * it is not used at this time as no function is supported yet.
 518      * Currently we make it always be 0 for all the devices and will set
 519      * the appropriate value once real function is implemented.
 520      */
 521     aml_append(method, aml_store(aml_int(0x0), aml_name("HDLE")));
 522     aml_append(method, aml_store(aml_arg(1), aml_name("REVS")));
 523     aml_append(method, aml_store(aml_arg(2), aml_name("FUNC")));
 524
 525     /*
 526      * tell QEMU about the real address of DSM memory, then QEMU
 527      * gets the control and fills the result in DSM memory.
 528      */
 529     aml_append(method, aml_store(dsm_mem, aml_name("NTFI")));
 530
 531     result_size = aml_local(1);
 532     aml_append(method, aml_store(aml_name("RLEN"), result_size));
 533     aml_append(method, aml_store(aml_shiftleft(result_size, aml_int(3)),
 534                                  result_size));
 535     aml_append(method, aml_create_field(aml_name("ODAT"), aml_int(0),
 536                                         result_size, "OBUF"));
 537     aml_append(method, aml_concatenate(aml_buffer(0, NULL), aml_name("OBUF"),
 538                                        aml_arg(6)));
 539     aml_append(method, aml_return(aml_arg(6)));
 540     aml_append(dev, method);
 541 }
 542
 543 static void nvdimm_build_device_dsm(Aml *dev)
 544 {
 545     Aml *method;
 546
 547     method = aml_method("_DSM", 4, AML_NOTSERIALIZED);
 548     aml_append(method, aml_return(aml_call4(NVDIMM_COMMON_DSM, aml_arg(0),
 549                                   aml_arg(1), aml_arg(2), aml_arg(3))));
 550     aml_append(dev, method);
 551 }
 552
 553 static void nvdimm_build_nvdimm_devices(GSList *device_list, Aml *root_dev)
 554 {
 555     for (; device_list; device_list = device_list->next) {
 556         DeviceState *dev = device_list->data;
 557         int slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
 558                                            NULL);
 559         uint32_t handle = nvdimm_slot_to_handle(slot);
 560         Aml *nvdimm_dev;
 561
 562         nvdimm_dev = aml_device("NV%02X", slot);
 563
 564         /*
 565          * ACPI 6.0: 9.20 NVDIMM Devices:
 566          *
 567          * _ADR object that is used to supply OSPM with unique address
 568          * of the NVDIMM device. This is done by returning the NFIT Device
 569          * handle that is used to identify the associated entries in ACPI
 570          * table NFIT or _FIT.
 571          */
 572         aml_append(nvdimm_dev, aml_name_decl("_ADR", aml_int(handle)));
 573
 574         nvdimm_build_device_dsm(nvdimm_dev);
 575         aml_append(root_dev, nvdimm_dev);
 576     }
 577 }
 578
 579 static void nvdimm_build_ssdt(GSList *device_list, GArray *table_offsets,
 580                               GArray *table_data, GArray *linker)
 581 {
 582     Aml *ssdt, *sb_scope, *dev, *field;
 583     int mem_addr_offset, nvdimm_ssdt;
 584
 585     acpi_add_table(table_offsets, table_data);
 586
 587     ssdt = init_aml_allocator();
 588     acpi_data_push(ssdt->buf, sizeof(AcpiTableHeader));
 589
 590     sb_scope = aml_scope("\\_SB");
 591
 592     dev = aml_device("NVDR");
 593
 594     /*
 595      * ACPI 6.0: 9.20 NVDIMM Devices:
 596      *
 597      * The ACPI Name Space device uses _HID of ACPI0012 to identify the root
 598      * NVDIMM interface device. Platform firmware is required to contain one
 599      * such device in _SB scope if NVDIMMs support is exposed by platform to
 600      * OSPM.
 601      * For each NVDIMM present or intended to be supported by platform,
 602      * platform firmware also exposes an ACPI Namespace Device under the
 603      * root device.
 604      */
 605     aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0012")));
 606
 607     /* map DSM memory and IO into ACPI namespace. */
 608     aml_append(dev, aml_operation_region("NPIO", AML_SYSTEM_IO,
 609                aml_int(NVDIMM_ACPI_IO_BASE), NVDIMM_ACPI_IO_LEN));
 610     aml_append(dev, aml_operation_region("NRAM", AML_SYSTEM_MEMORY,
 611                aml_name(NVDIMM_ACPI_MEM_ADDR), TARGET_PAGE_SIZE));
 612
 613     /*
 614      * DSM notifier:
 615      * NTFI: write the address of DSM memory and notify QEMU to emulate
 616      *       the access.
 617      *
 618      * It is the IO port so that accessing them will cause VM-exit, the
 619      * control will be transferred to QEMU.
 620      */
 621     field = aml_field("NPIO", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
 622     aml_append(field, aml_named_field("NTFI",
 623                sizeof(uint32_t) * BITS_PER_BYTE));
 624     aml_append(dev, field);
 625
 626     /*
 627      * DSM input:
 628      * HDLE: store device's handle, it's zero if the _DSM call happens
 629      *       on NVDIMM Root Device.
 630      * REVS: store the Arg1 of _DSM call.
 631      * FUNC: store the Arg2 of _DSM call.
 632      * ARG3: store the Arg3 of _DSM call.
 633      *
 634      * They are RAM mapping on host so that these accesses never cause
 635      * VM-EXIT.
 636      */
 637     field = aml_field("NRAM", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
 638     aml_append(field, aml_named_field("HDLE",
 639                sizeof(typeof_field(NvdimmDsmIn, handle)) * BITS_PER_BYTE));
 640     aml_append(field, aml_named_field("REVS",
 641                sizeof(typeof_field(NvdimmDsmIn, revision)) * BITS_PER_BYTE));
 642     aml_append(field, aml_named_field("FUNC",
 643                sizeof(typeof_field(NvdimmDsmIn, function)) * BITS_PER_BYTE));
 644     aml_append(field, aml_named_field("ARG3",
 645                (TARGET_PAGE_SIZE - offsetof(NvdimmDsmIn, arg3)) *
 646                 BITS_PER_BYTE));
 647     aml_append(dev, field);
 648
 649     /*
 650      * DSM output:
 651      * RLEN: the size of the buffer filled by QEMU.
 652      * ODAT: the buffer QEMU uses to store the result.
 653      *
 654      * Since the page is reused by both input and out, the input data
 655      * will be lost after storing new result into ODAT so we should fetch
 656      * all the input data before writing the result.
 657      */
 658     field = aml_field("NRAM", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
 659     aml_append(field, aml_named_field("RLEN",
 660                sizeof(typeof_field(NvdimmDsmOut, len)) * BITS_PER_BYTE));
 661     aml_append(field, aml_named_field("ODAT",
 662                (TARGET_PAGE_SIZE - offsetof(NvdimmDsmOut, data)) *
 663                      BITS_PER_BYTE));
 664     aml_append(dev, field);
 665
 666     nvdimm_build_common_dsm(dev);
 667     nvdimm_build_device_dsm(dev);
 668
 669     nvdimm_build_nvdimm_devices(device_list, dev);
 670
 671     aml_append(sb_scope, dev);
 672     aml_append(ssdt, sb_scope);
 673
 674     nvdimm_ssdt = table_data->len;
 675
 676     /* copy AML table into ACPI tables blob and patch header there */
 677     g_array_append_vals(table_data, ssdt->buf->data, ssdt->buf->len);
 678     mem_addr_offset = build_append_named_dword(table_data,
 679                                                NVDIMM_ACPI_MEM_ADDR);
 680
 681     bios_linker_loader_alloc(linker, NVDIMM_DSM_MEM_FILE, TARGET_PAGE_SIZE,
 682                              false /* high memory */);
 683     bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
 684                                    NVDIMM_DSM_MEM_FILE, table_data,
 685                                    table_data->data + mem_addr_offset,
 686                                    sizeof(uint32_t));
 687     build_header(linker, table_data,
 688         (void *)(table_data->data + nvdimm_ssdt),
 689         "SSDT", table_data->len - nvdimm_ssdt, 1, NULL, "NVDIMM");
 690     free_aml_allocator();
 691 }
 692
 693 void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
 694                        GArray *linker)
 695 {
 696     GSList *device_list;
 697
 698     /* no NVDIMM device is plugged. */
 699     device_list = nvdimm_get_plugged_device_list();
 700     if (!device_list) {
 701         return;
 702     }
 703     nvdimm_build_nfit(device_list, table_offsets, table_data, linker);
 704     nvdimm_build_ssdt(device_list, table_offsets, table_data, linker);
 705     g_slist_free(device_list);
 706 }