arch/x86/boot/compressed/eboot.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 /* -----------------------------------------------------------------------
   4  *
   5  *   Copyright 2011 Intel Corporation; author Matt Fleming
   6  *
   7  * ----------------------------------------------------------------------- */
   8
   9 #pragma GCC visibility push(hidden)
  10
  11 #include <linux/efi.h>
  12 #include <linux/pci.h>
  13
  14 #include <asm/efi.h>
  15 #include <asm/e820/types.h>
  16 #include <asm/setup.h>
  17 #include <asm/desc.h>
  18 #include <asm/boot.h>
  19
  20 #include "../string.h"
  21 #include "eboot.h"
  22
  23 static efi_system_table_t *sys_table;
  24 extern const bool efi_is64;
  25
  26 __pure efi_system_table_t *efi_system_table(void)
  27 {
  28         return sys_table;
  29 }
  30
  31 __attribute_const__ bool efi_is_64bit(void)
  32 {
  33         if (IS_ENABLED(CONFIG_EFI_MIXED))
  34                 return efi_is64;
  35         return IS_ENABLED(CONFIG_X86_64);
  36 }
  37
  38 static efi_status_t
  39 preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
  40 {
  41         struct pci_setup_rom *rom = NULL;
  42         efi_status_t status;
  43         unsigned long size;
  44         uint64_t romsize;
  45         void *romimage;
  46
  47         /*
  48          * Some firmware images contain EFI function pointers at the place where
  49          * the romimage and romsize fields are supposed to be. Typically the EFI
  50          * code is mapped at high addresses, translating to an unrealistically
  51          * large romsize. The UEFI spec limits the size of option ROMs to 16
  52          * MiB so we reject any ROMs over 16 MiB in size to catch this.
  53          */
  54         romimage = efi_table_attr(pci, romimage);
  55         romsize = efi_table_attr(pci, romsize);
  56         if (!romimage || !romsize || romsize > SZ_16M)
  57                 return EFI_INVALID_PARAMETER;
  58
  59         size = romsize + sizeof(*rom);
  60
  61         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
  62                              (void **)&rom);
  63         if (status != EFI_SUCCESS) {
  64                 efi_printk("Failed to allocate memory for 'rom'\n");
  65                 return status;
  66         }
  67
  68         memset(rom, 0, sizeof(*rom));
  69
  70         rom->data.type  = SETUP_PCI;
  71         rom->data.len   = size - sizeof(struct setup_data);
  72         rom->data.next  = 0;
  73         rom->pcilen     = pci->romsize;
  74         *__rom = rom;
  75
  76         status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
  77                                 PCI_VENDOR_ID, 1, &rom->vendor);
  78
  79         if (status != EFI_SUCCESS) {
  80                 efi_printk("Failed to read rom->vendor\n");
  81                 goto free_struct;
  82         }
  83
  84         status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
  85                                 PCI_DEVICE_ID, 1, &rom->devid);
  86
  87         if (status != EFI_SUCCESS) {
  88                 efi_printk("Failed to read rom->devid\n");
  89                 goto free_struct;
  90         }
  91
  92         status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,
  93                                 &rom->device, &rom->function);
  94
  95         if (status != EFI_SUCCESS)
  96                 goto free_struct;
  97
  98         memcpy(rom->romdata, romimage, romsize);
  99         return status;
 100
 101 free_struct:
 102         efi_bs_call(free_pool, rom);
 103         return status;
 104 }
 105
 106 /*
 107  * There's no way to return an informative status from this function,
 108  * because any analysis (and printing of error messages) needs to be
 109  * done directly at the EFI function call-site.
 110  *
 111  * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
 112  * just didn't find any PCI devices, but there's no way to tell outside
 113  * the context of the call.
 114  */
 115 static void setup_efi_pci(struct boot_params *params)
 116 {
 117         efi_status_t status;
 118         void **pci_handle = NULL;
 119         efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
 120         unsigned long size = 0;
 121         struct setup_data *data;
 122         efi_handle_t h;
 123         int i;
 124
 125         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 126                              &pci_proto, NULL, &size, pci_handle);
 127
 128         if (status == EFI_BUFFER_TOO_SMALL) {
 129                 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 130                                      (void **)&pci_handle);
 131
 132                 if (status != EFI_SUCCESS) {
 133                         efi_printk("Failed to allocate memory for 'pci_handle'\n");
 134                         return;
 135                 }
 136
 137                 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 138                                      &pci_proto, NULL, &size, pci_handle);
 139         }
 140
 141         if (status != EFI_SUCCESS)
 142                 goto free_handle;
 143
 144         data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
 145
 146         while (data && data->next)
 147                 data = (struct setup_data *)(unsigned long)data->next;
 148
 149         for_each_efi_handle(h, pci_handle, size, i) {
 150                 efi_pci_io_protocol_t *pci = NULL;
 151                 struct pci_setup_rom *rom;
 152
 153                 status = efi_bs_call(handle_protocol, h, &pci_proto,
 154                                      (void **)&pci);
 155                 if (status != EFI_SUCCESS || !pci)
 156                         continue;
 157
 158                 status = preserve_pci_rom_image(pci, &rom);
 159                 if (status != EFI_SUCCESS)
 160                         continue;
 161
 162                 if (data)
 163                         data->next = (unsigned long)rom;
 164                 else
 165                         params->hdr.setup_data = (unsigned long)rom;
 166
 167                 data = (struct setup_data *)rom;
 168         }
 169
 170 free_handle:
 171         efi_bs_call(free_pool, pci_handle);
 172 }
 173
 174 static void retrieve_apple_device_properties(struct boot_params *boot_params)
 175 {
 176         efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
 177         struct setup_data *data, *new;
 178         efi_status_t status;
 179         u32 size = 0;
 180         apple_properties_protocol_t *p;
 181
 182         status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);
 183         if (status != EFI_SUCCESS)
 184                 return;
 185
 186         if (efi_table_attr(p, version) != 0x10000) {
 187                 efi_printk("Unsupported properties proto version\n");
 188                 return;
 189         }
 190
 191         efi_call_proto(p, get_all, NULL, &size);
 192         if (!size)
 193                 return;
 194
 195         do {
 196                 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
 197                                      size + sizeof(struct setup_data),
 198                                      (void **)&new);
 199                 if (status != EFI_SUCCESS) {
 200                         efi_printk("Failed to allocate memory for 'properties'\n");
 201                         return;
 202                 }
 203
 204                 status = efi_call_proto(p, get_all, new->data, &size);
 205
 206                 if (status == EFI_BUFFER_TOO_SMALL)
 207                         efi_bs_call(free_pool, new);
 208         } while (status == EFI_BUFFER_TOO_SMALL);
 209
 210         new->type = SETUP_APPLE_PROPERTIES;
 211         new->len  = size;
 212         new->next = 0;
 213
 214         data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
 215         if (!data) {
 216                 boot_params->hdr.setup_data = (unsigned long)new;
 217         } else {
 218                 while (data->next)
 219                         data = (struct setup_data *)(unsigned long)data->next;
 220                 data->next = (unsigned long)new;
 221         }
 222 }
 223
 224 static const efi_char16_t apple[] = L"Apple";
 225
 226 static void setup_quirks(struct boot_params *boot_params)
 227 {
 228         efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
 229                 efi_table_attr(efi_system_table(), fw_vendor);
 230
 231         if (!memcmp(fw_vendor, apple, sizeof(apple))) {
 232                 if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
 233                         retrieve_apple_device_properties(boot_params);
 234         }
 235 }
 236
 237 /*
 238  * See if we have Universal Graphics Adapter (UGA) protocol
 239  */
 240 static efi_status_t
 241 setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)
 242 {
 243         efi_status_t status;
 244         u32 width, height;
 245         void **uga_handle = NULL;
 246         efi_uga_draw_protocol_t *uga = NULL, *first_uga;
 247         efi_handle_t handle;
 248         int i;
 249
 250         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 251                              (void **)&uga_handle);
 252         if (status != EFI_SUCCESS)
 253                 return status;
 254
 255         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 256                              uga_proto, NULL, &size, uga_handle);
 257         if (status != EFI_SUCCESS)
 258                 goto free_handle;
 259
 260         height = 0;
 261         width = 0;
 262
 263         first_uga = NULL;
 264         for_each_efi_handle(handle, uga_handle, size, i) {
 265                 efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;
 266                 u32 w, h, depth, refresh;
 267                 void *pciio;
 268
 269                 status = efi_bs_call(handle_protocol, handle, uga_proto,
 270                                      (void **)&uga);
 271                 if (status != EFI_SUCCESS)
 272                         continue;
 273
 274                 pciio = NULL;
 275                 efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio);
 276
 277                 status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh);
 278                 if (status == EFI_SUCCESS && (!first_uga || pciio)) {
 279                         width = w;
 280                         height = h;
 281
 282                         /*
 283                          * Once we've found a UGA supporting PCIIO,
 284                          * don't bother looking any further.
 285                          */
 286                         if (pciio)
 287                                 break;
 288
 289                         first_uga = uga;
 290                 }
 291         }
 292
 293         if (!width && !height)
 294                 goto free_handle;
 295
 296         /* EFI framebuffer */
 297         si->orig_video_isVGA    = VIDEO_TYPE_EFI;
 298
 299         si->lfb_depth           = 32;
 300         si->lfb_width           = width;
 301         si->lfb_height          = height;
 302
 303         si->red_size            = 8;
 304         si->red_pos             = 16;
 305         si->green_size          = 8;
 306         si->green_pos           = 8;
 307         si->blue_size           = 8;
 308         si->blue_pos            = 0;
 309         si->rsvd_size           = 8;
 310         si->rsvd_pos            = 24;
 311
 312 free_handle:
 313         efi_bs_call(free_pool, uga_handle);
 314
 315         return status;
 316 }
 317
 318 void setup_graphics(struct boot_params *boot_params)
 319 {
 320         efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
 321         struct screen_info *si;
 322         efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
 323         efi_status_t status;
 324         unsigned long size;
 325         void **gop_handle = NULL;
 326         void **uga_handle = NULL;
 327
 328         si = &boot_params->screen_info;
 329         memset(si, 0, sizeof(*si));
 330
 331         size = 0;
 332         status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 333                              &graphics_proto, NULL, &size, gop_handle);
 334         if (status == EFI_BUFFER_TOO_SMALL)
 335                 status = efi_setup_gop(si, &graphics_proto, size);
 336
 337         if (status != EFI_SUCCESS) {
 338                 size = 0;
 339                 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,
 340                                      &uga_proto, NULL, &size, uga_handle);
 341                 if (status == EFI_BUFFER_TOO_SMALL)
 342                         setup_uga(si, &uga_proto, size);
 343         }
 344 }
 345
 346 void startup_32(struct boot_params *boot_params);
 347
 348 void __noreturn efi_stub_entry(efi_handle_t handle,
 349                                efi_system_table_t *sys_table_arg,
 350                                struct boot_params *boot_params);
 351
 352 /*
 353  * Because the x86 boot code expects to be passed a boot_params we
 354  * need to create one ourselves (usually the bootloader would create
 355  * one for us).
 356  */
 357 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
 358                                    efi_system_table_t *sys_table_arg)
 359 {
 360         struct boot_params *boot_params;
 361         struct apm_bios_info *bi;
 362         struct setup_header *hdr;
 363         efi_loaded_image_t *image;
 364         efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
 365         int options_size = 0;
 366         efi_status_t status;
 367         char *cmdline_ptr;
 368         unsigned long ramdisk_addr;
 369         unsigned long ramdisk_size;
 370
 371         sys_table = sys_table_arg;
 372
 373         /* Check if we were booted by the EFI firmware */
 374         if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 375                 return EFI_INVALID_PARAMETER;
 376
 377         status = efi_bs_call(handle_protocol, handle, &proto, (void *)&image);
 378         if (status != EFI_SUCCESS) {
 379                 efi_printk("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
 380                 return status;
 381         }
 382
 383         status = efi_low_alloc(0x4000, 1, (unsigned long *)&boot_params);
 384         if (status != EFI_SUCCESS) {
 385                 efi_printk("Failed to allocate lowmem for boot params\n");
 386                 return status;
 387         }
 388
 389         memset(boot_params, 0x0, 0x4000);
 390
 391         hdr = &boot_params->hdr;
 392         bi = &boot_params->apm_bios_info;
 393
 394         /* Copy the second sector to boot_params */
 395         memcpy(&hdr->jump, image->image_base + 512, 512);
 396
 397         /*
 398          * Fill out some of the header fields ourselves because the
 399          * EFI firmware loader doesn't load the first sector.
 400          */
 401         hdr->root_flags = 1;
 402         hdr->vid_mode   = 0xffff;
 403         hdr->boot_flag  = 0xAA55;
 404
 405         hdr->type_of_loader = 0x21;
 406
 407         /* Convert unicode cmdline to ascii */
 408         cmdline_ptr = efi_convert_cmdline(image, &options_size);
 409         if (!cmdline_ptr)
 410                 goto fail;
 411
 412         hdr->cmd_line_ptr = (unsigned long)cmdline_ptr;
 413         /* Fill in upper bits of command line address, NOP on 32 bit  */
 414         boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32;
 415
 416         hdr->ramdisk_image = 0;
 417         hdr->ramdisk_size = 0;
 418
 419         /* Clear APM BIOS info */
 420         memset(bi, 0, sizeof(*bi));
 421
 422         status = efi_parse_options(cmdline_ptr);
 423         if (status != EFI_SUCCESS)
 424                 goto fail2;
 425
 426         status = handle_cmdline_files(image,
 427                                       (char *)(unsigned long)hdr->cmd_line_ptr,
 428                                       "initrd=", hdr->initrd_addr_max,
 429                                       &ramdisk_addr, &ramdisk_size);
 430
 431         if (status != EFI_SUCCESS &&
 432             hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) {
 433                 efi_printk("Trying to load files to higher address\n");
 434                 status = handle_cmdline_files(image,
 435                                       (char *)(unsigned long)hdr->cmd_line_ptr,
 436                                       "initrd=", -1UL,
 437                                       &ramdisk_addr, &ramdisk_size);
 438         }
 439
 440         if (status != EFI_SUCCESS)
 441                 goto fail2;
 442         hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
 443         hdr->ramdisk_size  = ramdisk_size & 0xffffffff;
 444         boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32;
 445         boot_params->ext_ramdisk_size  = (u64)ramdisk_size >> 32;
 446
 447         hdr->code32_start = (u32)(unsigned long)startup_32;
 448
 449         efi_stub_entry(handle, sys_table, boot_params);
 450         /* not reached */
 451
 452 fail2:
 453         efi_free(options_size, hdr->cmd_line_ptr);
 454 fail:
 455         efi_free(0x4000, (unsigned long)boot_params);
 456
 457         return status;
 458 }
 459
 460 static void add_e820ext(struct boot_params *params,
 461                         struct setup_data *e820ext, u32 nr_entries)
 462 {
 463         struct setup_data *data;
 464
 465         e820ext->type = SETUP_E820_EXT;
 466         e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
 467         e820ext->next = 0;
 468
 469         data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
 470
 471         while (data && data->next)
 472                 data = (struct setup_data *)(unsigned long)data->next;
 473
 474         if (data)
 475                 data->next = (unsigned long)e820ext;
 476         else
 477                 params->hdr.setup_data = (unsigned long)e820ext;
 478 }
 479
 480 static efi_status_t
 481 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
 482 {
 483         struct boot_e820_entry *entry = params->e820_table;
 484         struct efi_info *efi = &params->efi_info;
 485         struct boot_e820_entry *prev = NULL;
 486         u32 nr_entries;
 487         u32 nr_desc;
 488         int i;
 489
 490         nr_entries = 0;
 491         nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
 492
 493         for (i = 0; i < nr_desc; i++) {
 494                 efi_memory_desc_t *d;
 495                 unsigned int e820_type = 0;
 496                 unsigned long m = efi->efi_memmap;
 497
 498 #ifdef CONFIG_X86_64
 499                 m |= (u64)efi->efi_memmap_hi << 32;
 500 #endif
 501
 502                 d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i);
 503                 switch (d->type) {
 504                 case EFI_RESERVED_TYPE:
 505                 case EFI_RUNTIME_SERVICES_CODE:
 506                 case EFI_RUNTIME_SERVICES_DATA:
 507                 case EFI_MEMORY_MAPPED_IO:
 508                 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
 509                 case EFI_PAL_CODE:
 510                         e820_type = E820_TYPE_RESERVED;
 511                         break;
 512
 513                 case EFI_UNUSABLE_MEMORY:
 514                         e820_type = E820_TYPE_UNUSABLE;
 515                         break;
 516
 517                 case EFI_ACPI_RECLAIM_MEMORY:
 518                         e820_type = E820_TYPE_ACPI;
 519                         break;
 520
 521                 case EFI_LOADER_CODE:
 522                 case EFI_LOADER_DATA:
 523                 case EFI_BOOT_SERVICES_CODE:
 524                 case EFI_BOOT_SERVICES_DATA:
 525                 case EFI_CONVENTIONAL_MEMORY:
 526                         if (efi_soft_reserve_enabled() &&
 527                             (d->attribute & EFI_MEMORY_SP))
 528                                 e820_type = E820_TYPE_SOFT_RESERVED;
 529                         else
 530                                 e820_type = E820_TYPE_RAM;
 531                         break;
 532
 533                 case EFI_ACPI_MEMORY_NVS:
 534                         e820_type = E820_TYPE_NVS;
 535                         break;
 536
 537                 case EFI_PERSISTENT_MEMORY:
 538                         e820_type = E820_TYPE_PMEM;
 539                         break;
 540
 541                 default:
 542                         continue;
 543                 }
 544
 545                 /* Merge adjacent mappings */
 546                 if (prev && prev->type == e820_type &&
 547                     (prev->addr + prev->size) == d->phys_addr) {
 548                         prev->size += d->num_pages << 12;
 549                         continue;
 550                 }
 551
 552                 if (nr_entries == ARRAY_SIZE(params->e820_table)) {
 553                         u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
 554                                    sizeof(struct setup_data);
 555
 556                         if (!e820ext || e820ext_size < need)
 557                                 return EFI_BUFFER_TOO_SMALL;
 558
 559                         /* boot_params map full, switch to e820 extended */
 560                         entry = (struct boot_e820_entry *)e820ext->data;
 561                 }
 562
 563                 entry->addr = d->phys_addr;
 564                 entry->size = d->num_pages << PAGE_SHIFT;
 565                 entry->type = e820_type;
 566                 prev = entry++;
 567                 nr_entries++;
 568         }
 569
 570         if (nr_entries > ARRAY_SIZE(params->e820_table)) {
 571                 u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
 572
 573                 add_e820ext(params, e820ext, nr_e820ext);
 574                 nr_entries -= nr_e820ext;
 575         }
 576
 577         params->e820_entries = (u8)nr_entries;
 578
 579         return EFI_SUCCESS;
 580 }
 581
 582 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
 583                                   u32 *e820ext_size)
 584 {
 585         efi_status_t status;
 586         unsigned long size;
 587
 588         size = sizeof(struct setup_data) +
 589                 sizeof(struct e820_entry) * nr_desc;
 590
 591         if (*e820ext) {
 592                 efi_bs_call(free_pool, *e820ext);
 593                 *e820ext = NULL;
 594                 *e820ext_size = 0;
 595         }
 596
 597         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
 598                              (void **)e820ext);
 599         if (status == EFI_SUCCESS)
 600                 *e820ext_size = size;
 601
 602         return status;
 603 }
 604
 605 static efi_status_t allocate_e820(struct boot_params *params,
 606                                   struct setup_data **e820ext,
 607                                   u32 *e820ext_size)
 608 {
 609         unsigned long map_size, desc_size, buff_size;
 610         struct efi_boot_memmap boot_map;
 611         efi_memory_desc_t *map;
 612         efi_status_t status;
 613         __u32 nr_desc;
 614
 615         boot_map.map            = &map;
 616         boot_map.map_size       = &map_size;
 617         boot_map.desc_size      = &desc_size;
 618         boot_map.desc_ver       = NULL;
 619         boot_map.key_ptr        = NULL;
 620         boot_map.buff_size      = &buff_size;
 621
 622         status = efi_get_memory_map(&boot_map);
 623         if (status != EFI_SUCCESS)
 624                 return status;
 625
 626         nr_desc = buff_size / desc_size;
 627
 628         if (nr_desc > ARRAY_SIZE(params->e820_table)) {
 629                 u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table);
 630
 631                 status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
 632                 if (status != EFI_SUCCESS)
 633                         return status;
 634         }
 635
 636         return EFI_SUCCESS;
 637 }
 638
 639 struct exit_boot_struct {
 640         struct boot_params      *boot_params;
 641         struct efi_info         *efi;
 642 };
 643
 644 static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
 645                                    void *priv)
 646 {
 647         const char *signature;
 648         struct exit_boot_struct *p = priv;
 649
 650         signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
 651                                    : EFI32_LOADER_SIGNATURE;
 652         memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
 653
 654         p->efi->efi_systab              = (unsigned long)efi_system_table();
 655         p->efi->efi_memdesc_size        = *map->desc_size;
 656         p->efi->efi_memdesc_version     = *map->desc_ver;
 657         p->efi->efi_memmap              = (unsigned long)*map->map;
 658         p->efi->efi_memmap_size         = *map->map_size;
 659
 660 #ifdef CONFIG_X86_64
 661         p->efi->efi_systab_hi           = (unsigned long)efi_system_table() >> 32;
 662         p->efi->efi_memmap_hi           = (unsigned long)*map->map >> 32;
 663 #endif
 664
 665         return EFI_SUCCESS;
 666 }
 667
 668 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
 669 {
 670         unsigned long map_sz, key, desc_size, buff_size;
 671         efi_memory_desc_t *mem_map;
 672         struct setup_data *e820ext = NULL;
 673         __u32 e820ext_size = 0;
 674         efi_status_t status;
 675         __u32 desc_version;
 676         struct efi_boot_memmap map;
 677         struct exit_boot_struct priv;
 678
 679         map.map                 = &mem_map;
 680         map.map_size            = &map_sz;
 681         map.desc_size           = &desc_size;
 682         map.desc_ver            = &desc_version;
 683         map.key_ptr             = &key;
 684         map.buff_size           = &buff_size;
 685         priv.boot_params        = boot_params;
 686         priv.efi                = &boot_params->efi_info;
 687
 688         status = allocate_e820(boot_params, &e820ext, &e820ext_size);
 689         if (status != EFI_SUCCESS)
 690                 return status;
 691
 692         /* Might as well exit boot services now */
 693         status = efi_exit_boot_services(handle, &map, &priv, exit_boot_func);
 694         if (status != EFI_SUCCESS)
 695                 return status;
 696
 697         /* Historic? */
 698         boot_params->alt_mem_k  = 32 * 1024;
 699
 700         status = setup_e820(boot_params, e820ext, e820ext_size);
 701         if (status != EFI_SUCCESS)
 702                 return status;
 703
 704         return EFI_SUCCESS;
 705 }
 706
 707 /*
 708  * On success we return a pointer to a boot_params structure, and NULL
 709  * on failure.
 710  */
 711 struct boot_params *efi_main(efi_handle_t handle,
 712                              efi_system_table_t *sys_table_arg,
 713                              struct boot_params *boot_params)
 714 {
 715         struct desc_ptr *gdt = NULL;
 716         struct setup_header *hdr = &boot_params->hdr;
 717         efi_status_t status;
 718         struct desc_struct *desc;
 719         unsigned long cmdline_paddr;
 720
 721         sys_table = sys_table_arg;
 722
 723         /* Check if we were booted by the EFI firmware */
 724         if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
 725                 goto fail;
 726
 727         /*
 728          * make_boot_params() may have been called before efi_main(), in which
 729          * case this is the second time we parse the cmdline. This is ok,
 730          * parsing the cmdline multiple times does not have side-effects.
 731          */
 732         cmdline_paddr = ((u64)hdr->cmd_line_ptr |
 733                          ((u64)boot_params->ext_cmd_line_ptr << 32));
 734         efi_parse_options((char *)cmdline_paddr);
 735
 736         /*
 737          * If the boot loader gave us a value for secure_boot then we use that,
 738          * otherwise we ask the BIOS.
 739          */
 740         if (boot_params->secure_boot == efi_secureboot_mode_unset)
 741                 boot_params->secure_boot = efi_get_secureboot();
 742
 743         /* Ask the firmware to clear memory on unclean shutdown */
 744         efi_enable_reset_attack_mitigation();
 745
 746         efi_random_get_seed();
 747
 748         efi_retrieve_tpm2_eventlog();
 749
 750         setup_graphics(boot_params);
 751
 752         setup_efi_pci(boot_params);
 753
 754         setup_quirks(boot_params);
 755
 756         status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(*gdt),
 757                              (void **)&gdt);
 758         if (status != EFI_SUCCESS) {
 759                 efi_printk("Failed to allocate memory for 'gdt' structure\n");
 760                 goto fail;
 761         }
 762
 763         gdt->size = 0x800;
 764         status = efi_low_alloc(gdt->size, 8, (unsigned long *)&gdt->address);
 765         if (status != EFI_SUCCESS) {
 766                 efi_printk("Failed to allocate memory for 'gdt'\n");
 767                 goto fail;
 768         }
 769
 770         /*
 771          * If the kernel isn't already loaded at the preferred load
 772          * address, relocate it.
 773          */
 774         if (hdr->pref_address != hdr->code32_start) {
 775                 unsigned long bzimage_addr = hdr->code32_start;
 776                 status = efi_relocate_kernel(&bzimage_addr,
 777                                              hdr->init_size, hdr->init_size,
 778                                              hdr->pref_address,
 779                                              hdr->kernel_alignment,
 780                                              LOAD_PHYSICAL_ADDR);
 781                 if (status != EFI_SUCCESS) {
 782                         efi_printk("efi_relocate_kernel() failed!\n");
 783                         goto fail;
 784                 }
 785
 786                 hdr->pref_address = hdr->code32_start;
 787                 hdr->code32_start = bzimage_addr;
 788         }
 789
 790         status = exit_boot(boot_params, handle);
 791         if (status != EFI_SUCCESS) {
 792                 efi_printk("exit_boot() failed!\n");
 793                 goto fail;
 794         }
 795
 796         memset((char *)gdt->address, 0x0, gdt->size);
 797         desc = (struct desc_struct *)gdt->address;
 798
 799         /* The first GDT is a dummy. */
 800         desc++;
 801
 802         if (IS_ENABLED(CONFIG_X86_64)) {
 803                 /* __KERNEL32_CS */
 804                 desc->limit0    = 0xffff;
 805                 desc->base0     = 0x0000;
 806                 desc->base1     = 0x0000;
 807                 desc->type      = SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
 808                 desc->s         = DESC_TYPE_CODE_DATA;
 809                 desc->dpl       = 0;
 810                 desc->p         = 1;
 811                 desc->limit1    = 0xf;
 812                 desc->avl       = 0;
 813                 desc->l         = 0;
 814                 desc->d         = SEG_OP_SIZE_32BIT;
 815                 desc->g         = SEG_GRANULARITY_4KB;
 816                 desc->base2     = 0x00;
 817
 818                 desc++;
 819         } else {
 820                 /* Second entry is unused on 32-bit */
 821                 desc++;
 822         }
 823
 824         /* __KERNEL_CS */
 825         desc->limit0    = 0xffff;
 826         desc->base0     = 0x0000;
 827         desc->base1     = 0x0000;
 828         desc->type      = SEG_TYPE_CODE | SEG_TYPE_EXEC_READ;
 829         desc->s         = DESC_TYPE_CODE_DATA;
 830         desc->dpl       = 0;
 831         desc->p         = 1;
 832         desc->limit1    = 0xf;
 833         desc->avl       = 0;
 834
 835         if (IS_ENABLED(CONFIG_X86_64)) {
 836                 desc->l = 1;
 837                 desc->d = 0;
 838         } else {
 839                 desc->l = 0;
 840                 desc->d = SEG_OP_SIZE_32BIT;
 841         }
 842         desc->g         = SEG_GRANULARITY_4KB;
 843         desc->base2     = 0x00;
 844         desc++;
 845
 846         /* __KERNEL_DS */
 847         desc->limit0    = 0xffff;
 848         desc->base0     = 0x0000;
 849         desc->base1     = 0x0000;
 850         desc->type      = SEG_TYPE_DATA | SEG_TYPE_READ_WRITE;
 851         desc->s         = DESC_TYPE_CODE_DATA;
 852         desc->dpl       = 0;
 853         desc->p         = 1;
 854         desc->limit1    = 0xf;
 855         desc->avl       = 0;
 856         desc->l         = 0;
 857         desc->d         = SEG_OP_SIZE_32BIT;
 858         desc->g         = SEG_GRANULARITY_4KB;
 859         desc->base2     = 0x00;
 860         desc++;
 861
 862         if (IS_ENABLED(CONFIG_X86_64)) {
 863                 /* Task segment value */
 864                 desc->limit0    = 0x0000;
 865                 desc->base0     = 0x0000;
 866                 desc->base1     = 0x0000;
 867                 desc->type      = SEG_TYPE_TSS;
 868                 desc->s         = 0;
 869                 desc->dpl       = 0;
 870                 desc->p         = 1;
 871                 desc->limit1    = 0x0;
 872                 desc->avl       = 0;
 873                 desc->l         = 0;
 874                 desc->d         = 0;
 875                 desc->g         = SEG_GRANULARITY_4KB;
 876                 desc->base2     = 0x00;
 877                 desc++;
 878         }
 879
 880         asm volatile("cli");
 881         asm volatile ("lgdt %0" : : "m" (*gdt));
 882
 883         return boot_params;
 884 fail:
 885         efi_printk("efi_main() failed!\n");
 886
 887         for (;;)
 888                 asm("hlt");
 889 }