drivers/firmware/efi/libstub/x86-stub.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 /* -----------------------------------------------------------------------
   4  *
   5  *   Copyright 2011 Intel Corporation; author Matt Fleming
   6  *
   7  * ----------------------------------------------------------------------- */
   8
   9 #include <linux/efi.h>
  10 #include <linux/pci.h>
  11
  12 #include <asm/efi.h>
  13 #include <asm/e820/types.h>
  14 #include <asm/setup.h>
  15 #include <asm/desc.h>
  16 #include <asm/boot.h>
  17
  18 #include "efistub.h"
  19
  20 static efi_system_table_t *sys_table;
  21 extern const bool efi_is64;
  22
  23 __pure efi_system_table_t *efi_system_table(void)
  24 {
  25         return sys_table;
  26 }
  27
  28 __attribute_const__ bool efi_is_64bit(void)
  29 {
  30         if (IS_ENABLED(CONFIG_EFI_MIXED))
  31                 return efi_is64;
  32         return IS_ENABLED(CONFIG_X86_64);
  33 }
  34
  35 static efi_status_t
  36 preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
  37 {
  38         struct pci_setup_rom *rom = NULL;
  39         efi_status_t status;
  40         unsigned long size;
  41         uint64_t romsize;
  42         void *romimage;
  43
  44         /*
  45          * Some firmware images contain EFI function pointers at the place where
  46          * the romimage and romsize fields are supposed to be. Typically the EFI
  47          * code is mapped at high addresses, translating to an unrealistically
  48          * large romsize. The UEFI spec limits the size of option ROMs to 16
  49          * MiB so we reject any ROMs over 16 MiB in size to catch this.
  50          */
  51         romimage = efi_table_attr(pci, romimage);
  52         romsize = efi_table_attr(pci, romsize);
  53         if (!romimage || !romsize || romsize > SZ_16M)
  54                 return EFI_INVALID_PARAMETER;
  55
  56         size = romsize + sizeof(*rom);
  57
  58         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
  59                              (void **)&rom);
  60         if (status != EFI_SUCCESS) {
  61                 efi_printk("Failed to allocate memory for 'rom'\n");
  62                 return status;
  63         }
  64
  65         memset(rom, 0, sizeof(*rom));
  66
  67         rom->data.type  = SETUP_PCI;
  68         rom->data.len   = size - sizeof(struct setup_data);
  69         rom->data.next  = 0;
  70         rom->pcilen     = pci->romsize;
  71         *__rom = rom;
  72
  73         status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
  74                                 PCI_VENDOR_ID, 1, &rom->vendor);
  75
  76         if (status != EFI_SUCCESS) {
  77                 efi_printk("Failed to read rom->vendor\n");
  78                 goto free_struct;
  79         }
  80
  81         status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
  82                                 PCI_DEVICE_ID, 1, &rom->devid);
  83
  84         if (status != EFI_SUCCESS) {
  85                 efi_printk("Failed to read rom->devid\n");
  86                 goto free_struct;
  87         }
  88
  89         status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,
  90                                 &rom->device, &rom->function);
  91
  92         if (status != EFI_SUCCESS)
  93                 goto free_struct;
  94
  95         memcpy(rom->romdata, romimage, romsize);
  96         return status;
  97
  98 free_struct:
  99         efi_bs_call(free_pool, rom);
 100         return status;
 101 }
 102
 103 /*
 104  * There's no way to return an informative status from this function,
 105  * because any analysis (and printing of error messages) needs to be
 106  * done directly at the EFI function call-site.
 107  *
 108  * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
 109  * just didn't find any PCI devices, but there's no way to tell outside
 110  * the context of the call.
 111  */
 112 static void setup_efi_pci(struct boot_params *params)
 113 {
 114         efi_status_t status;
 115         void **pci_handle = NULL;
 116         efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
 117         unsigned long size = 0;
 118         struct setup_data *data;
 119         efi_handle_t h;
 120         int i;
 121
 122         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 123                              &pci_proto, NULL, &size, pci_handle);
 124
 125         if (status == EFI_BUFFER_TOO_SMALL) {
 126                 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 127                                      (void **)&pci_handle);
 128
 129                 if (status != EFI_SUCCESS) {
 130                         efi_printk("Failed to allocate memory for 'pci_handle'\n");
 131                         return;
 132                 }
 133
 134                 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 135                                      &pci_proto, NULL, &size, pci_handle);
 136         }
 137
 138         if (status != EFI_SUCCESS)
 139                 goto free_handle;
 140
 141         data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
 142
 143         while (data && data->next)
 144                 data = (struct setup_data *)(unsigned long)data->next;
 145
 146         for_each_efi_handle(h, pci_handle, size, i) {
 147                 efi_pci_io_protocol_t *pci = NULL;
 148                 struct pci_setup_rom *rom;
 149
 150                 status = efi_bs_call(handle_protocol, h, &pci_proto,
 151                                      (void **)&pci);
 152                 if (status != EFI_SUCCESS || !pci)
 153                         continue;
 154
 155                 status = preserve_pci_rom_image(pci, &rom);
 156                 if (status != EFI_SUCCESS)
 157                         continue;
 158
 159                 if (data)
 160                         data->next = (unsigned long)rom;
 161                 else
 162                         params->hdr.setup_data = (unsigned long)rom;
 163
 164                 data = (struct setup_data *)rom;
 165         }
 166
 167 free_handle:
 168         efi_bs_call(free_pool, pci_handle);
 169 }
 170
 171 static void retrieve_apple_device_properties(struct boot_params *boot_params)
 172 {
 173         efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
 174         struct setup_data *data, *new;
 175         efi_status_t status;
 176         u32 size = 0;
 177         apple_properties_protocol_t *p;
 178
 179         status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);
 180         if (status != EFI_SUCCESS)
 181                 return;
 182
 183         if (efi_table_attr(p, version) != 0x10000) {
 184                 efi_printk("Unsupported properties proto version\n");
 185                 return;
 186         }
 187
 188         efi_call_proto(p, get_all, NULL, &size);
 189         if (!size)
 190                 return;
 191
 192         do {
 193                 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
 194                                      size + sizeof(struct setup_data),
 195                                      (void **)&new);
 196                 if (status != EFI_SUCCESS) {
 197                         efi_printk("Failed to allocate memory for 'properties'\n");
 198                         return;
 199                 }
 200
 201                 status = efi_call_proto(p, get_all, new->data, &size);
 202
 203                 if (status == EFI_BUFFER_TOO_SMALL)
 204                         efi_bs_call(free_pool, new);
 205         } while (status == EFI_BUFFER_TOO_SMALL);
 206
 207         new->type = SETUP_APPLE_PROPERTIES;
 208         new->len  = size;
 209         new->next = 0;
 210
 211         data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
 212         if (!data) {
 213                 boot_params->hdr.setup_data = (unsigned long)new;
 214         } else {
 215                 while (data->next)
 216                         data = (struct setup_data *)(unsigned long)data->next;
 217                 data->next = (unsigned long)new;
 218         }
 219 }
 220
 221 static const efi_char16_t apple[] = L"Apple";
 222
 223 static void setup_quirks(struct boot_params *boot_params)
 224 {
 225         efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
 226                 efi_table_attr(efi_system_table(), fw_vendor);
 227
 228         if (!memcmp(fw_vendor, apple, sizeof(apple))) {
 229                 if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
 230                         retrieve_apple_device_properties(boot_params);
 231         }
 232 }
 233
 234 /*
 235  * See if we have Universal Graphics Adapter (UGA) protocol
 236  */
 237 static efi_status_t
 238 setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
 239 {
 240         efi_status_t status;
 241         u32 width, height;
 242         void **uga_handle = NULL;
 243         efi_uga_draw_protocol_t *uga = NULL, *first_uga;
 244         efi_handle_t handle;
 245         int i;
 246
 247         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 248                              (void **)&uga_handle);
 249         if (status != EFI_SUCCESS)
 250                 return status;
 251
 252         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 253                              uga_proto, NULL, &size, uga_handle);
 254         if (status != EFI_SUCCESS)
 255                 goto free_handle;
 256
 257         height = 0;
 258         width = 0;
 259
 260         first_uga = NULL;
 261         for_each_efi_handle(handle, uga_handle, size, i) {
 262                 efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
 263                 u32 w, h, depth, refresh;
 264                 void *pciio;
 265
 266                 status = efi_bs_call(handle_protocol, handle, uga_proto,
 267                                      (void **)&uga);
 268                 if (status != EFI_SUCCESS)
 269                         continue;
 270
 271                 pciio = NULL;
 272                 efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio);
 273
 274                 status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh);
 275                 if (status == EFI_SUCCESS && (!first_uga || pciio)) {
 276                         width = w;
 277                         height = h;
 278
 279                         /*
 280                          * Once we've found a UGA supporting PCIIO,
 281                          * don't bother looking any further.
 282                          */
 283                         if (pciio)
 284                                 break;
 285
 286                         first_uga = uga;
 287                 }
 288         }
 289
 290         if (!width && !height)
 291                 goto free_handle;
 292
 293         /* EFI framebuffer */
 294         si->orig_video_isVGA    = VIDEO_TYPE_EFI;
 295
 296         si->lfb_depth           = 32;
 297         si->lfb_width           = width;
 298         si->lfb_height          = height;
 299
 300         si->red_size            = 8;
 301         si->red_pos             = 16;
 302         si->green_size          = 8;
 303         si->green_pos           = 8;
 304         si->blue_size           = 8;
 305         si->blue_pos            = 0;
 306         si->rsvd_size           = 8;
 307         si->rsvd_pos            = 24;
 308
 309 free_handle:
 310         efi_bs_call(free_pool, uga_handle);
 311
 312         return status;
 313 }
 314
 315 static void setup_graphics(struct boot_params *boot_params)
 316 {
 317         efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
 318         struct screen_info *si;
 319         efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
 320         efi_status_t status;
 321         unsigned long size;
 322         void **gop_handle = NULL;
 323         void **uga_handle = NULL;
 324
 325         si = &boot_params->screen_info;
 326         memset(si, 0, sizeof(*si));
 327
 328         size = 0;
 329         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 330                              &graphics_proto, NULL, &size, gop_handle);
 331         if (status == EFI_BUFFER_TOO_SMALL)
 332                 status = efi_setup_gop(si, &graphics_proto, size);
 333
 334         if (status != EFI_SUCCESS) {
 335                 size = 0;
 336                 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 337                                      &uga_proto, NULL, &size, uga_handle);
 338                 if (status == EFI_BUFFER_TOO_SMALL)
 339                         setup_uga(si, &uga_proto, size);
 340         }
 341 }
 342
 343
 344 static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
 345 {
 346         efi_bs_call(exit, handle, status, 0, NULL);
 347         unreachable();
 348 }
 349
 350 void startup_32(struct boot_params *boot_params);
 351
 352 void __noreturn efi_stub_entry(efi_handle_t handle,
 353                                efi_system_table_t *sys_table_arg,
 354                                struct boot_params *boot_params);
 355
 356 /*
 357  * Because the x86 boot code expects to be passed a boot_params we
 358  * need to create one ourselves (usually the bootloader would create
 359  * one for us).
 360  */
 361 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 362                                    efi_system_table_t *sys_table_arg)
 363 {
 364         struct boot_params *boot_params;
 365         struct setup_header *hdr;
 366         efi_loaded_image_t *image;
 367         efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
 368         int options_size = 0;
 369         efi_status_t status;
 370         char *cmdline_ptr;
 371         unsigned long ramdisk_addr;
 372         unsigned long ramdisk_size;
 373         bool above4g;
 374
 375         sys_table = sys_table_arg;
 376
 377         /* Check if we were booted by the EFI firmware */
 378         if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 379                 efi_exit(handle, EFI_INVALID_PARAMETER);
 380
 381         status = efi_bs_call(handle_protocol, handle, &proto, (void *)&image);
 382         if (status != EFI_SUCCESS) {
 383                 efi_printk("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
 384                 efi_exit(handle, status);
 385         }
 386
 387         hdr = &((struct boot_params *)efi_table_attr(image, image_base))->hdr;
 388         above4g = hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G;
 389
 390         status = efi_allocate_pages(0x4000, (unsigned long *)&boot_params,
 391                                     above4g ? ULONG_MAX : UINT_MAX);
 392         if (status != EFI_SUCCESS) {
 393                 efi_printk("Failed to allocate lowmem for boot params\n");
 394                 efi_exit(handle, status);
 395         }
 396
 397         memset(boot_params, 0x0, 0x4000);
 398
 399         hdr = &boot_params->hdr;
 400
 401         /* Copy the second sector to boot_params */
 402         memcpy(&hdr->jump, efi_table_attr(image, image_base) + 512, 512);
 403
 404         /*
 405          * Fill out some of the header fields ourselves because the
 406          * EFI firmware loader doesn't load the first sector.
 407          */
 408         hdr->root_flags = 1;
 409         hdr->vid_mode   = 0xffff;
 410         hdr->boot_flag  = 0xAA55;
 411
 412         hdr->type_of_loader = 0x21;
 413
 414         /* Convert unicode cmdline to ascii */
 415         cmdline_ptr = efi_convert_cmdline(image, &options_size,
 416                                           above4g ? ULONG_MAX : UINT_MAX);
 417         if (!cmdline_ptr)
 418                 goto fail;
 419
 420         hdr->cmd_line_ptr = (unsigned long)cmdline_ptr;
 421         /* Fill in upper bits of command line address, NOP on 32 bit  */
 422         boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32;
 423
 424         hdr->ramdisk_image = 0;
 425         hdr->ramdisk_size = 0;
 426
 427         status = efi_parse_options(cmdline_ptr);
 428         if (status != EFI_SUCCESS)
 429                 goto fail2;
 430
 431         if (!noinitrd()) {
 432                 status = efi_load_initrd(image, &ramdisk_addr, &ramdisk_size,
 433                                          hdr->initrd_addr_max,
 434                                          above4g ? ULONG_MAX
 435                                                  : hdr->initrd_addr_max);
 436                 if (status != EFI_SUCCESS)
 437                         goto fail2;
 438                 hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
 439                 hdr->ramdisk_size  = ramdisk_size & 0xffffffff;
 440                 boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32;
 441                 boot_params->ext_ramdisk_size  = (u64)ramdisk_size >> 32;
 442         }
 443
 444         efi_stub_entry(handle, sys_table, boot_params);
 445         /* not reached */
 446
 447 fail2:
 448         efi_free(options_size, (unsigned long)cmdline_ptr);
 449 fail:
 450         efi_free(0x4000, (unsigned long)boot_params);
 451
 452         efi_exit(handle, status);
 453 }
 454
 455 static void add_e820ext(struct boot_params *params,
 456                         struct setup_data *e820ext, u32 nr_entries)
 457 {
 458         struct setup_data *data;
 459
 460         e820ext->type = SETUP_E820_EXT;
 461         e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
 462         e820ext->next = 0;
 463
 464         data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
 465
 466         while (data && data->next)
 467                 data = (struct setup_data *)(unsigned long)data->next;
 468
 469         if (data)
 470                 data->next = (unsigned long)e820ext;
 471         else
 472                 params->hdr.setup_data = (unsigned long)e820ext;
 473 }
 474
 475 static efi_status_t
 476 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
 477 {
 478         struct boot_e820_entry *entry = params->e820_table;
 479         struct efi_info *efi = &params->efi_info;
 480         struct boot_e820_entry *prev = NULL;
 481         u32 nr_entries;
 482         u32 nr_desc;
 483         int i;
 484
 485         nr_entries = 0;
 486         nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
 487
 488         for (i = 0; i < nr_desc; i++) {
 489                 efi_memory_desc_t *d;
 490                 unsigned int e820_type = 0;
 491                 unsigned long m = efi->efi_memmap;
 492
 493 #ifdef CONFIG_X86_64
 494                 m |= (u64)efi->efi_memmap_hi << 32;
 495 #endif
 496
 497                 d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
 498                 switch (d->type) {
 499                 case EFI_RESERVED_TYPE:
 500                 case EFI_RUNTIME_SERVICES_CODE:
 501                 case EFI_RUNTIME_SERVICES_DATA:
 502                 case EFI_MEMORY_MAPPED_IO:
 503                 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
 504                 case EFI_PAL_CODE:
 505                         e820_type = E820_TYPE_RESERVED;
 506                         break;
 507
 508                 case EFI_UNUSABLE_MEMORY:
 509                         e820_type = E820_TYPE_UNUSABLE;
 510                         break;
 511
 512                 case EFI_ACPI_RECLAIM_MEMORY:
 513                         e820_type = E820_TYPE_ACPI;
 514                         break;
 515
 516                 case EFI_LOADER_CODE:
 517                 case EFI_LOADER_DATA:
 518                 case EFI_BOOT_SERVICES_CODE:
 519                 case EFI_BOOT_SERVICES_DATA:
 520                 case EFI_CONVENTIONAL_MEMORY:
 521                         if (efi_soft_reserve_enabled() &&
 522                             (d->attribute & EFI_MEMORY_SP))
 523                                 e820_type = E820_TYPE_SOFT_RESERVED;
 524                         else
 525                                 e820_type = E820_TYPE_RAM;
 526                         break;
 527
 528                 case EFI_ACPI_MEMORY_NVS:
 529                         e820_type = E820_TYPE_NVS;
 530                         break;
 531
 532                 case EFI_PERSISTENT_MEMORY:
 533                         e820_type = E820_TYPE_PMEM;
 534                         break;
 535
 536                 default:
 537                         continue;
 538                 }
 539
 540                 /* Merge adjacent mappings */
 541                 if (prev && prev->type == e820_type &&
 542                     (prev->addr + prev->size) == d->phys_addr) {
 543                         prev->size += d->num_pages << 12;
 544                         continue;
 545                 }
 546
 547                 if (nr_entries == ARRAY_SIZE(params->e820_table)) {
 548                         u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
 549                                    sizeof(struct setup_data);
 550
 551                         if (!e820ext || e820ext_size < need)
 552                                 return EFI_BUFFER_TOO_SMALL;
 553
 554                         /* boot_params map full, switch to e820 extended */
 555                         entry = (struct boot_e820_entry *)e820ext->data;
 556                 }
 557
 558                 entry->addr = d->phys_addr;
 559                 entry->size = d->num_pages << PAGE_SHIFT;
 560                 entry->type = e820_type;
 561                 prev = entry++;
 562                 nr_entries++;
 563         }
 564
 565         if (nr_entries > ARRAY_SIZE(params->e820_table)) {
 566                 u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
 567
 568                 add_e820ext(params, e820ext, nr_e820ext);
 569                 nr_entries -= nr_e820ext;
 570         }
 571
 572         params->e820_entries = (u8)nr_entries;
 573
 574         return EFI_SUCCESS;
 575 }
 576
 577 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
 578                                   u32 *e820ext_size)
 579 {
 580         efi_status_t status;
 581         unsigned long size;
 582
 583         size = sizeof(struct setup_data) +
 584                 sizeof(struct e820_entry) * nr_desc;
 585
 586         if (*e820ext) {
 587                 efi_bs_call(free_pool, *e820ext);
 588                 *e820ext = NULL;
 589                 *e820ext_size = 0;
 590         }
 591
 592         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 593                              (void **)e820ext);
 594         if (status == EFI_SUCCESS)
 595                 *e820ext_size = size;
 596
 597         return status;
 598 }
 599
 600 static efi_status_t allocate_e820(struct boot_params *params,
 601                                   struct setup_data **e820ext,
 602                                   u32 *e820ext_size)
 603 {
 604         unsigned long map_size, desc_size, buff_size;
 605         struct efi_boot_memmap boot_map;
 606         efi_memory_desc_t *map;
 607         efi_status_t status;
 608         __u32 nr_desc;
 609
 610         boot_map.map            = &map;
 611         boot_map.map_size       = &map_size;
 612         boot_map.desc_size      = &desc_size;
 613         boot_map.desc_ver       = NULL;
 614         boot_map.key_ptr        = NULL;
 615         boot_map.buff_size      = &buff_size;
 616
 617         status = efi_get_memory_map(&boot_map);
 618         if (status != EFI_SUCCESS)
 619                 return status;
 620
 621         nr_desc = buff_size / desc_size;
 622
 623         if (nr_desc > ARRAY_SIZE(params->e820_table)) {
 624                 u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
 625
 626                 status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
 627                 if (status != EFI_SUCCESS)
 628                         return status;
 629         }
 630
 631         return EFI_SUCCESS;
 632 }
 633
 634 struct exit_boot_struct {
 635         struct boot_params      *boot_params;
 636         struct efi_info         *efi;
 637 };
 638
 639 static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
 640                                    void *priv)
 641 {
 642         const char *signature;
 643         struct exit_boot_struct *p = priv;
 644
 645         signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
 646                                    : EFI32_LOADER_SIGNATURE;
 647         memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
 648
 649         p->efi->efi_systab              = (unsigned long)efi_system_table();
 650         p->efi->efi_memdesc_size        = *map->desc_size;
 651         p->efi->efi_memdesc_version     = *map->desc_ver;
 652         p->efi->efi_memmap              = (unsigned long)*map->map;
 653         p->efi->efi_memmap_size         = *map->map_size;
 654
 655 #ifdef CONFIG_X86_64
 656         p->efi->efi_systab_hi           = (unsigned long)efi_system_table() >> 32;
 657         p->efi->efi_memmap_hi           = (unsigned long)*map->map >> 32;
 658 #endif
 659
 660         return EFI_SUCCESS;
 661 }
 662
 663 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
 664 {
 665         unsigned long map_sz, key, desc_size, buff_size;
 666         efi_memory_desc_t *mem_map;
 667         struct setup_data *e820ext = NULL;
 668         __u32 e820ext_size = 0;
 669         efi_status_t status;
 670         __u32 desc_version;
 671         struct efi_boot_memmap map;
 672         struct exit_boot_struct priv;
 673
 674         map.map                 = &mem_map;
 675         map.map_size            = &map_sz;
 676         map.desc_size           = &desc_size;
 677         map.desc_ver            = &desc_version;
 678         map.key_ptr             = &key;
 679         map.buff_size           = &buff_size;
 680         priv.boot_params        = boot_params;
 681         priv.efi                = &boot_params->efi_info;
 682
 683         status = allocate_e820(boot_params, &e820ext, &e820ext_size);
 684         if (status != EFI_SUCCESS)
 685                 return status;
 686
 687         /* Might as well exit boot services now */
 688         status = efi_exit_boot_services(handle, &map, &priv, exit_boot_func);
 689         if (status != EFI_SUCCESS)
 690                 return status;
 691
 692         /* Historic? */
 693         boot_params->alt_mem_k  = 32 * 1024;
 694
 695         status = setup_e820(boot_params, e820ext, e820ext_size);
 696         if (status != EFI_SUCCESS)
 697                 return status;
 698
 699         return EFI_SUCCESS;
 700 }
 701
 702 /*
 703  * On success we return a pointer to a boot_params structure, and NULL
 704  * on failure.
 705  */
 706 struct boot_params *efi_main(efi_handle_t handle,
 707                              efi_system_table_t *sys_table_arg,
 708                              struct boot_params *boot_params)
 709 {
 710         unsigned long bzimage_addr = (unsigned long)startup_32;
 711         struct setup_header *hdr = &boot_params->hdr;
 712         efi_status_t status;
 713         unsigned long cmdline_paddr;
 714
 715         sys_table = sys_table_arg;
 716
 717         /* Check if we were booted by the EFI firmware */
 718         if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 719                 efi_exit(handle, EFI_INVALID_PARAMETER);
 720
 721         /*
 722          * If the kernel isn't already loaded at the preferred load
 723          * address, relocate it.
 724          */
 725         if (bzimage_addr != hdr->pref_address) {
 726                 status = efi_relocate_kernel(&bzimage_addr,
 727                                              hdr->init_size, hdr->init_size,
 728                                              hdr->pref_address,
 729                                              hdr->kernel_alignment,
 730                                              LOAD_PHYSICAL_ADDR);
 731                 if (status != EFI_SUCCESS) {
 732                         efi_printk("efi_relocate_kernel() failed!\n");
 733                         goto fail;
 734                 }
 735         }
 736         hdr->code32_start = (u32)bzimage_addr;
 737
 738         /*
 739          * efi_pe_entry() may have been called before efi_main(), in which
 740          * case this is the second time we parse the cmdline. This is ok,
 741          * parsing the cmdline multiple times does not have side-effects.
 742          */
 743         cmdline_paddr = ((u64)hdr->cmd_line_ptr |
 744                          ((u64)boot_params->ext_cmd_line_ptr << 32));
 745         efi_parse_options((char *)cmdline_paddr);
 746
 747         /*
 748          * At this point, an initrd may already have been loaded, either by
 749          * the bootloader and passed via bootparams, or loaded from a initrd=
 750          * command line option by efi_pe_entry() above. In either case, we
 751          * permit an initrd loaded from the LINUX_EFI_INITRD_MEDIA_GUID device
 752          * path to supersede it.
 753          */
 754         if (!noinitrd()) {
 755                 unsigned long addr, size;
 756                 unsigned long max_addr = hdr->initrd_addr_max;
 757
 758                 if (hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G)
 759                         max_addr = ULONG_MAX;
 760
 761                 status = efi_load_initrd_dev_path(&addr, &size, max_addr);
 762                 if (status == EFI_SUCCESS) {
 763                         hdr->ramdisk_image              = (u32)addr;
 764                         hdr->ramdisk_size               = (u32)size;
 765                         boot_params->ext_ramdisk_image  = (u64)addr >> 32;
 766                         boot_params->ext_ramdisk_size   = (u64)size >> 32;
 767                 } else if (status != EFI_NOT_FOUND) {
 768                         efi_printk("efi_load_initrd_dev_path() failed!\n");
 769                         goto fail;
 770                 }
 771         }
 772
 773         /*
 774          * If the boot loader gave us a value for secure_boot then we use that,
 775          * otherwise we ask the BIOS.
 776          */
 777         if (boot_params->secure_boot == efi_secureboot_mode_unset)
 778                 boot_params->secure_boot = efi_get_secureboot();
 779
 780         /* Ask the firmware to clear memory on unclean shutdown */
 781         efi_enable_reset_attack_mitigation();
 782
 783         efi_random_get_seed();
 784
 785         efi_retrieve_tpm2_eventlog();
 786
 787         setup_graphics(boot_params);
 788
 789         setup_efi_pci(boot_params);
 790
 791         setup_quirks(boot_params);
 792
 793         status = exit_boot(boot_params, handle);
 794         if (status != EFI_SUCCESS) {
 795                 efi_printk("exit_boot() failed!\n");
 796                 goto fail;
 797         }
 798
 799         return boot_params;
 800 fail:
 801         efi_printk("efi_main() failed!\n");
 802
 803         efi_exit(handle, status);
 804 }