xref: /openbmc/qemu/hw/acpi/nvdimm.c (revision b917da4c)
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 }
707