lib/efi_loader/efi_runtime.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI application runtime services
   4  *
   5  *  Copyright (c) 2016 Alexander Graf
   6  */
   7
   8 #include <common.h>
   9 #include <command.h>
  10 #include <dm.h>
  11 #include <efi_loader.h>
  12 #include <rtc.h>
  13
  14 /* For manual relocation support */
  15 DECLARE_GLOBAL_DATA_PTR;
  16
  17 struct efi_runtime_mmio_list {
  18         struct list_head link;
  19         void **ptr;
  20         u64 paddr;
  21         u64 len;
  22 };
  23
  24 /* This list contains all runtime available mmio regions */
  25 LIST_HEAD(efi_runtime_mmio);
  26
  27 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void);
  28 static efi_status_t __efi_runtime EFIAPI efi_device_error(void);
  29 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void);
  30
  31 /*
  32  * TODO(sjg@chromium.org): These defines and structs should come from the elf
  33  * header for each arch (or a generic header) rather than being repeated here.
  34  */
  35 #if defined(CONFIG_ARM64)
  36 #define R_RELATIVE      1027
  37 #define R_MASK          0xffffffffULL
  38 #define IS_RELA         1
  39 #elif defined(CONFIG_ARM)
  40 #define R_RELATIVE      23
  41 #define R_MASK          0xffULL
  42 #elif defined(CONFIG_X86)
  43 #include <asm/elf.h>
  44 #define R_RELATIVE      R_386_RELATIVE
  45 #define R_MASK          0xffULL
  46 #elif defined(CONFIG_RISCV)
  47 #include <elf.h>
  48 #define R_RELATIVE      R_RISCV_RELATIVE
  49 #define R_MASK          0xffULL
  50 #define IS_RELA         1
  51
  52 struct dyn_sym {
  53         ulong foo1;
  54         ulong addr;
  55         u32 foo2;
  56         u32 foo3;
  57 };
  58 #ifdef CONFIG_CPU_RISCV_32
  59 #define R_ABSOLUTE      R_RISCV_32
  60 #define SYM_INDEX       8
  61 #else
  62 #define R_ABSOLUTE      R_RISCV_64
  63 #define SYM_INDEX       32
  64 #endif
  65 #else
  66 #error Need to add relocation awareness
  67 #endif
  68
  69 struct elf_rel {
  70         ulong *offset;
  71         ulong info;
  72 };
  73
  74 struct elf_rela {
  75         ulong *offset;
  76         ulong info;
  77         long addend;
  78 };
  79
  80 /*
  81  * EFI Runtime code lives in 2 stages. In the first stage, U-Boot and an EFI
  82  * payload are running concurrently at the same time. In this mode, we can
  83  * handle a good number of runtime callbacks
  84  */
  85
  86 static void EFIAPI efi_reset_system_boottime(
  87                         enum efi_reset_type reset_type,
  88                         efi_status_t reset_status,
  89                         unsigned long data_size, void *reset_data)
  90 {
  91         struct efi_event *evt;
  92
  93         EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
  94                   reset_data);
  95
  96         /* Notify reset */
  97         list_for_each_entry(evt, &efi_events, link) {
  98                 if (evt->group &&
  99                     !guidcmp(evt->group,
 100                              &efi_guid_event_group_reset_system)) {
 101                         efi_signal_event(evt, false);
 102                         break;
 103                 }
 104         }
 105         switch (reset_type) {
 106         case EFI_RESET_COLD:
 107         case EFI_RESET_WARM:
 108         case EFI_RESET_PLATFORM_SPECIFIC:
 109                 do_reset(NULL, 0, 0, NULL);
 110                 break;
 111         case EFI_RESET_SHUTDOWN:
 112                 /* We don't have anything to map this to */
 113                 break;
 114         }
 115
 116         while (1) { }
 117 }
 118
 119 static efi_status_t EFIAPI efi_get_time_boottime(
 120                         struct efi_time *time,
 121                         struct efi_time_cap *capabilities)
 122 {
 123 #if defined(CONFIG_CMD_DATE) && defined(CONFIG_DM_RTC)
 124         struct rtc_time tm;
 125         int r;
 126         struct udevice *dev;
 127
 128         EFI_ENTRY("%p %p", time, capabilities);
 129
 130         r = uclass_get_device(UCLASS_RTC, 0, &dev);
 131         if (r)
 132                 return EFI_EXIT(EFI_DEVICE_ERROR);
 133
 134         r = dm_rtc_get(dev, &tm);
 135         if (r)
 136                 return EFI_EXIT(EFI_DEVICE_ERROR);
 137
 138         memset(time, 0, sizeof(*time));
 139         time->year = tm.tm_year;
 140         time->month = tm.tm_mon;
 141         time->day = tm.tm_mday;
 142         time->hour = tm.tm_hour;
 143         time->minute = tm.tm_min;
 144         time->daylight = tm.tm_isdst;
 145
 146         return EFI_EXIT(EFI_SUCCESS);
 147 #else
 148         return EFI_DEVICE_ERROR;
 149 #endif
 150 }
 151
 152 /* Boards may override the helpers below to implement RTS functionality */
 153
 154 void __weak __efi_runtime EFIAPI efi_reset_system(
 155                         enum efi_reset_type reset_type,
 156                         efi_status_t reset_status,
 157                         unsigned long data_size, void *reset_data)
 158 {
 159         /* Nothing we can do */
 160         while (1) { }
 161 }
 162
 163 efi_status_t __weak efi_reset_system_init(void)
 164 {
 165         return EFI_SUCCESS;
 166 }
 167
 168 efi_status_t __weak __efi_runtime EFIAPI efi_get_time(
 169                         struct efi_time *time,
 170                         struct efi_time_cap *capabilities)
 171 {
 172         /* Nothing we can do */
 173         return EFI_DEVICE_ERROR;
 174 }
 175
 176 efi_status_t __weak efi_get_time_init(void)
 177 {
 178         return EFI_SUCCESS;
 179 }
 180
 181 struct efi_runtime_detach_list_struct {
 182         void *ptr;
 183         void *patchto;
 184 };
 185
 186 static const struct efi_runtime_detach_list_struct efi_runtime_detach_list[] = {
 187         {
 188                 /* do_reset is gone */
 189                 .ptr = &efi_runtime_services.reset_system,
 190                 .patchto = efi_reset_system,
 191         }, {
 192                 /* invalidate_*cache_all are gone */
 193                 .ptr = &efi_runtime_services.set_virtual_address_map,
 194                 .patchto = &efi_invalid_parameter,
 195         }, {
 196                 /* RTC accessors are gone */
 197                 .ptr = &efi_runtime_services.get_time,
 198                 .patchto = &efi_get_time,
 199         }, {
 200                 /* Clean up system table */
 201                 .ptr = &systab.con_in,
 202                 .patchto = NULL,
 203         }, {
 204                 /* Clean up system table */
 205                 .ptr = &systab.con_out,
 206                 .patchto = NULL,
 207         }, {
 208                 /* Clean up system table */
 209                 .ptr = &systab.std_err,
 210                 .patchto = NULL,
 211         }, {
 212                 /* Clean up system table */
 213                 .ptr = &systab.boottime,
 214                 .patchto = NULL,
 215         }, {
 216                 .ptr = &efi_runtime_services.get_variable,
 217                 .patchto = &efi_device_error,
 218         }, {
 219                 .ptr = &efi_runtime_services.get_next_variable_name,
 220                 .patchto = &efi_device_error,
 221         }, {
 222                 .ptr = &efi_runtime_services.set_variable,
 223                 .patchto = &efi_device_error,
 224         }
 225 };
 226
 227 static bool efi_runtime_tobedetached(void *p)
 228 {
 229         int i;
 230
 231         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++)
 232                 if (efi_runtime_detach_list[i].ptr == p)
 233                         return true;
 234
 235         return false;
 236 }
 237
 238 static void efi_runtime_detach(ulong offset)
 239 {
 240         int i;
 241         ulong patchoff = offset - (ulong)gd->relocaddr;
 242
 243         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++) {
 244                 ulong patchto = (ulong)efi_runtime_detach_list[i].patchto;
 245                 ulong *p = efi_runtime_detach_list[i].ptr;
 246                 ulong newaddr = patchto ? (patchto + patchoff) : 0;
 247
 248                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 249                 *p = newaddr;
 250         }
 251 }
 252
 253 /* Relocate EFI runtime to uboot_reloc_base = offset */
 254 void efi_runtime_relocate(ulong offset, struct efi_mem_desc *map)
 255 {
 256 #ifdef IS_RELA
 257         struct elf_rela *rel = (void*)&__efi_runtime_rel_start;
 258 #else
 259         struct elf_rel *rel = (void*)&__efi_runtime_rel_start;
 260         static ulong lastoff = CONFIG_SYS_TEXT_BASE;
 261 #endif
 262
 263         debug("%s: Relocating to offset=%lx\n", __func__, offset);
 264         for (; (ulong)rel < (ulong)&__efi_runtime_rel_stop; rel++) {
 265                 ulong base = CONFIG_SYS_TEXT_BASE;
 266                 ulong *p;
 267                 ulong newaddr;
 268
 269                 p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
 270
 271                 debug("%s: rel->info=%#lx *p=%#lx rel->offset=%p\n", __func__, rel->info, *p, rel->offset);
 272
 273                 switch (rel->info & R_MASK) {
 274                 case R_RELATIVE:
 275 #ifdef IS_RELA
 276                 newaddr = rel->addend + offset - CONFIG_SYS_TEXT_BASE;
 277 #else
 278                 newaddr = *p - lastoff + offset;
 279 #endif
 280                         break;
 281 #ifdef R_ABSOLUTE
 282                 case R_ABSOLUTE: {
 283                         ulong symidx = rel->info >> SYM_INDEX;
 284                         extern struct dyn_sym __dyn_sym_start[];
 285                         newaddr = __dyn_sym_start[symidx].addr + offset;
 286                         break;
 287                 }
 288 #endif
 289                 default:
 290                         continue;
 291                 }
 292
 293                 /* Check if the relocation is inside bounds */
 294                 if (map && ((newaddr < map->virtual_start) ||
 295                     newaddr > (map->virtual_start +
 296                               (map->num_pages << EFI_PAGE_SHIFT)))) {
 297                         if (!efi_runtime_tobedetached(p))
 298                                 printf("U-Boot EFI: Relocation at %p is out of "
 299                                        "range (%lx)\n", p, newaddr);
 300                         continue;
 301                 }
 302
 303                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 304                 *p = newaddr;
 305                 flush_dcache_range((ulong)p & ~(EFI_CACHELINE_SIZE - 1),
 306                         ALIGN((ulong)&p[1], EFI_CACHELINE_SIZE));
 307         }
 308
 309 #ifndef IS_RELA
 310         lastoff = offset;
 311 #endif
 312
 313         invalidate_icache_all();
 314 }
 315
 316 static efi_status_t EFIAPI efi_set_virtual_address_map(
 317                         unsigned long memory_map_size,
 318                         unsigned long descriptor_size,
 319                         uint32_t descriptor_version,
 320                         struct efi_mem_desc *virtmap)
 321 {
 322         ulong runtime_start = (ulong)&__efi_runtime_start &
 323                               ~(ulong)EFI_PAGE_MASK;
 324         int n = memory_map_size / descriptor_size;
 325         int i;
 326
 327         EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
 328                   descriptor_version, virtmap);
 329
 330         /* Rebind mmio pointers */
 331         for (i = 0; i < n; i++) {
 332                 struct efi_mem_desc *map = (void*)virtmap +
 333                                            (descriptor_size * i);
 334                 struct list_head *lhandle;
 335                 efi_physical_addr_t map_start = map->physical_start;
 336                 efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
 337                 efi_physical_addr_t map_end = map_start + map_len;
 338
 339                 /* Adjust all mmio pointers in this region */
 340                 list_for_each(lhandle, &efi_runtime_mmio) {
 341                         struct efi_runtime_mmio_list *lmmio;
 342
 343                         lmmio = list_entry(lhandle,
 344                                            struct efi_runtime_mmio_list,
 345                                            link);
 346                         if ((map_start <= lmmio->paddr) &&
 347                             (map_end >= lmmio->paddr)) {
 348                                 u64 off = map->virtual_start - map_start;
 349                                 uintptr_t new_addr = lmmio->paddr + off;
 350                                 *lmmio->ptr = (void *)new_addr;
 351                         }
 352                 }
 353         }
 354
 355         /* Move the actual runtime code over */
 356         for (i = 0; i < n; i++) {
 357                 struct efi_mem_desc *map;
 358
 359                 map = (void*)virtmap + (descriptor_size * i);
 360                 if (map->type == EFI_RUNTIME_SERVICES_CODE) {
 361                         ulong new_offset = map->virtual_start -
 362                                            (runtime_start - gd->relocaddr);
 363
 364                         efi_runtime_relocate(new_offset, map);
 365                         /* Once we're virtual, we can no longer handle
 366                            complex callbacks */
 367                         efi_runtime_detach(new_offset);
 368                         return EFI_EXIT(EFI_SUCCESS);
 369                 }
 370         }
 371
 372         return EFI_EXIT(EFI_INVALID_PARAMETER);
 373 }
 374
 375 efi_status_t efi_add_runtime_mmio(void *mmio_ptr, u64 len)
 376 {
 377         struct efi_runtime_mmio_list *newmmio;
 378         u64 pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
 379         uint64_t addr = *(uintptr_t *)mmio_ptr;
 380         uint64_t retaddr;
 381
 382         retaddr = efi_add_memory_map(addr, pages, EFI_MMAP_IO, false);
 383         if (retaddr != addr)
 384                 return EFI_OUT_OF_RESOURCES;
 385
 386         newmmio = calloc(1, sizeof(*newmmio));
 387         if (!newmmio)
 388                 return EFI_OUT_OF_RESOURCES;
 389         newmmio->ptr = mmio_ptr;
 390         newmmio->paddr = *(uintptr_t *)mmio_ptr;
 391         newmmio->len = len;
 392         list_add_tail(&newmmio->link, &efi_runtime_mmio);
 393
 394         return EFI_SUCCESS;
 395 }
 396
 397 /*
 398  * In the second stage, U-Boot has disappeared. To isolate our runtime code
 399  * that at this point still exists from the rest, we put it into a special
 400  * section.
 401  *
 402  *        !!WARNING!!
 403  *
 404  * This means that we can not rely on any code outside of this file in any
 405  * function or variable below this line.
 406  *
 407  * Please keep everything fully self-contained and annotated with
 408  * __efi_runtime and __efi_runtime_data markers.
 409  */
 410
 411 /*
 412  * Relocate the EFI runtime stub to a different place. We need to call this
 413  * the first time we expose the runtime interface to a user and on set virtual
 414  * address map calls.
 415  */
 416
 417 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void)
 418 {
 419         return EFI_UNSUPPORTED;
 420 }
 421
 422 static efi_status_t __efi_runtime EFIAPI efi_device_error(void)
 423 {
 424         return EFI_DEVICE_ERROR;
 425 }
 426
 427 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void)
 428 {
 429         return EFI_INVALID_PARAMETER;
 430 }
 431
 432 efi_status_t __efi_runtime EFIAPI efi_update_capsule(
 433                         struct efi_capsule_header **capsule_header_array,
 434                         efi_uintn_t capsule_count,
 435                         u64 scatter_gather_list)
 436 {
 437         return EFI_UNSUPPORTED;
 438 }
 439
 440 efi_status_t __efi_runtime EFIAPI efi_query_capsule_caps(
 441                         struct efi_capsule_header **capsule_header_array,
 442                         efi_uintn_t capsule_count,
 443                         u64 maximum_capsule_size,
 444                         u32 reset_type)
 445 {
 446         return EFI_UNSUPPORTED;
 447 }
 448
 449 efi_status_t __efi_runtime EFIAPI efi_query_variable_info(
 450                         u32 attributes,
 451                         u64 *maximum_variable_storage_size,
 452                         u64 *remaining_variable_storage_size,
 453                         u64 *maximum_variable_size)
 454 {
 455         return EFI_UNSUPPORTED;
 456 }
 457
 458 struct efi_runtime_services __efi_runtime_data efi_runtime_services = {
 459         .hdr = {
 460                 .signature = EFI_RUNTIME_SERVICES_SIGNATURE,
 461                 .revision = EFI_RUNTIME_SERVICES_REVISION,
 462                 .headersize = sizeof(struct efi_table_hdr),
 463         },
 464         .get_time = &efi_get_time_boottime,
 465         .set_time = (void *)&efi_device_error,
 466         .get_wakeup_time = (void *)&efi_unimplemented,
 467         .set_wakeup_time = (void *)&efi_unimplemented,
 468         .set_virtual_address_map = &efi_set_virtual_address_map,
 469         .convert_pointer = (void *)&efi_invalid_parameter,
 470         .get_variable = efi_get_variable,
 471         .get_next_variable_name = efi_get_next_variable_name,
 472         .set_variable = efi_set_variable,
 473         .get_next_high_mono_count = (void *)&efi_device_error,
 474         .reset_system = &efi_reset_system_boottime,
 475         .update_capsule = efi_update_capsule,
 476         .query_capsule_caps = efi_query_capsule_caps,
 477         .query_variable_info = efi_query_variable_info,
 478 };