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 <elf.h>
  12 #include <efi_loader.h>
  13 #include <rtc.h>
  14
  15 /* For manual relocation support */
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 struct efi_runtime_mmio_list {
  19         struct list_head link;
  20         void **ptr;
  21         u64 paddr;
  22         u64 len;
  23 };
  24
  25 /* This list contains all runtime available mmio regions */
  26 LIST_HEAD(efi_runtime_mmio);
  27
  28 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void);
  29 static efi_status_t __efi_runtime EFIAPI efi_device_error(void);
  30 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void);
  31
  32 /*
  33  * TODO(sjg@chromium.org): These defines and structs should come from the elf
  34  * header for each arch (or a generic header) rather than being repeated here.
  35  */
  36 #if defined(__aarch64__)
  37 #define R_RELATIVE      R_AARCH64_RELATIVE
  38 #define R_MASK          0xffffffffULL
  39 #define IS_RELA         1
  40 #elif defined(__arm__)
  41 #define R_RELATIVE      R_ARM_RELATIVE
  42 #define R_MASK          0xffULL
  43 #elif defined(__x86_64__) || defined(__i386__)
  44 #define R_RELATIVE      R_386_RELATIVE
  45 #define R_MASK          0xffULL
  46 #elif defined(__riscv)
  47 #define R_RELATIVE      R_RISCV_RELATIVE
  48 #define R_MASK          0xffULL
  49 #define IS_RELA         1
  50
  51 struct dyn_sym {
  52         ulong foo1;
  53         ulong addr;
  54         u32 foo2;
  55         u32 foo3;
  56 };
  57 #if (__riscv_xlen == 32)
  58 #define R_ABSOLUTE      R_RISCV_32
  59 #define SYM_INDEX       8
  60 #elif (__riscv_xlen == 64)
  61 #define R_ABSOLUTE      R_RISCV_64
  62 #define SYM_INDEX       32
  63 #else
  64 #error unknown riscv target
  65 #endif
  66 #else
  67 #error Need to add relocation awareness
  68 #endif
  69
  70 struct elf_rel {
  71         ulong *offset;
  72         ulong info;
  73 };
  74
  75 struct elf_rela {
  76         ulong *offset;
  77         ulong info;
  78         long addend;
  79 };
  80
  81 /*
  82  * EFI Runtime code lives in 2 stages. In the first stage, U-Boot and an EFI
  83  * payload are running concurrently at the same time. In this mode, we can
  84  * handle a good number of runtime callbacks
  85  */
  86
  87 /**
  88  * efi_update_table_header_crc32() - Update crc32 in table header
  89  *
  90  * @table:      EFI table
  91  */
  92 void __efi_runtime efi_update_table_header_crc32(struct efi_table_hdr *table)
  93 {
  94         table->crc32 = 0;
  95         table->crc32 = crc32(0, (const unsigned char *)table,
  96                              table->headersize);
  97 }
  98
  99 static void EFIAPI efi_reset_system_boottime(
 100                         enum efi_reset_type reset_type,
 101                         efi_status_t reset_status,
 102                         unsigned long data_size, void *reset_data)
 103 {
 104         struct efi_event *evt;
 105
 106         EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
 107                   reset_data);
 108
 109         /* Notify reset */
 110         list_for_each_entry(evt, &efi_events, link) {
 111                 if (evt->group &&
 112                     !guidcmp(evt->group,
 113                              &efi_guid_event_group_reset_system)) {
 114                         efi_signal_event(evt, false);
 115                         break;
 116                 }
 117         }
 118         switch (reset_type) {
 119         case EFI_RESET_COLD:
 120         case EFI_RESET_WARM:
 121         case EFI_RESET_PLATFORM_SPECIFIC:
 122                 do_reset(NULL, 0, 0, NULL);
 123                 break;
 124         case EFI_RESET_SHUTDOWN:
 125                 /* We don't have anything to map this to */
 126                 break;
 127         }
 128
 129         while (1) { }
 130 }
 131
 132 /**
 133  * efi_get_time_boottime - get current time
 134  *
 135  * This function implements the GetTime runtime service.
 136  * See the Unified Extensible Firmware Interface (UEFI) specification
 137  * for details.
 138  *
 139  * @time:               pointer to structure to receive current time
 140  * @capabilities:       pointer to structure to receive RTC properties
 141  * Return Value:        status code
 142  */
 143 static efi_status_t EFIAPI efi_get_time_boottime(
 144                         struct efi_time *time,
 145                         struct efi_time_cap *capabilities)
 146 {
 147 #ifdef CONFIG_DM_RTC
 148         efi_status_t ret = EFI_SUCCESS;
 149         int r;
 150         struct rtc_time tm;
 151         struct udevice *dev;
 152
 153         EFI_ENTRY("%p %p", time, capabilities);
 154
 155         if (!time) {
 156                 ret = EFI_INVALID_PARAMETER;
 157                 goto out;
 158         }
 159
 160         r = uclass_get_device(UCLASS_RTC, 0, &dev);
 161         if (!r)
 162                 r = dm_rtc_get(dev, &tm);
 163         if (r) {
 164                 ret = EFI_DEVICE_ERROR;
 165                 goto out;
 166         }
 167
 168         memset(time, 0, sizeof(*time));
 169         time->year = tm.tm_year;
 170         time->month = tm.tm_mon;
 171         time->day = tm.tm_mday;
 172         time->hour = tm.tm_hour;
 173         time->minute = tm.tm_min;
 174         time->second = tm.tm_sec;
 175         time->daylight = EFI_TIME_ADJUST_DAYLIGHT;
 176         if (tm.tm_isdst > 0)
 177                 time->daylight |= EFI_TIME_IN_DAYLIGHT;
 178         time->timezone = EFI_UNSPECIFIED_TIMEZONE;
 179
 180         if (capabilities) {
 181                 /* Set reasonable dummy values */
 182                 capabilities->resolution = 1;           /* 1 Hz */
 183                 capabilities->accuracy = 100000000;     /* 100 ppm */
 184                 capabilities->sets_to_zero = false;
 185         }
 186 out:
 187         return EFI_EXIT(ret);
 188 #else
 189         EFI_ENTRY("%p %p", time, capabilities);
 190         return EFI_EXIT(EFI_DEVICE_ERROR);
 191 #endif
 192 }
 193
 194 /* Boards may override the helpers below to implement RTS functionality */
 195
 196 void __weak __efi_runtime EFIAPI efi_reset_system(
 197                         enum efi_reset_type reset_type,
 198                         efi_status_t reset_status,
 199                         unsigned long data_size, void *reset_data)
 200 {
 201         /* Nothing we can do */
 202         while (1) { }
 203 }
 204
 205 efi_status_t __weak efi_reset_system_init(void)
 206 {
 207         return EFI_SUCCESS;
 208 }
 209
 210 efi_status_t __weak __efi_runtime EFIAPI efi_get_time(
 211                         struct efi_time *time,
 212                         struct efi_time_cap *capabilities)
 213 {
 214         /* Nothing we can do */
 215         return EFI_DEVICE_ERROR;
 216 }
 217
 218 struct efi_runtime_detach_list_struct {
 219         void *ptr;
 220         void *patchto;
 221 };
 222
 223 static const struct efi_runtime_detach_list_struct efi_runtime_detach_list[] = {
 224         {
 225                 /* do_reset is gone */
 226                 .ptr = &efi_runtime_services.reset_system,
 227                 .patchto = efi_reset_system,
 228         }, {
 229                 /* invalidate_*cache_all are gone */
 230                 .ptr = &efi_runtime_services.set_virtual_address_map,
 231                 .patchto = &efi_invalid_parameter,
 232         }, {
 233                 /* RTC accessors are gone */
 234                 .ptr = &efi_runtime_services.get_time,
 235                 .patchto = &efi_get_time,
 236         }, {
 237                 /* Clean up system table */
 238                 .ptr = &systab.con_in,
 239                 .patchto = NULL,
 240         }, {
 241                 /* Clean up system table */
 242                 .ptr = &systab.con_out,
 243                 .patchto = NULL,
 244         }, {
 245                 /* Clean up system table */
 246                 .ptr = &systab.std_err,
 247                 .patchto = NULL,
 248         }, {
 249                 /* Clean up system table */
 250                 .ptr = &systab.boottime,
 251                 .patchto = NULL,
 252         }, {
 253                 .ptr = &efi_runtime_services.get_variable,
 254                 .patchto = &efi_device_error,
 255         }, {
 256                 .ptr = &efi_runtime_services.get_next_variable_name,
 257                 .patchto = &efi_device_error,
 258         }, {
 259                 .ptr = &efi_runtime_services.set_variable,
 260                 .patchto = &efi_device_error,
 261         }
 262 };
 263
 264 static bool efi_runtime_tobedetached(void *p)
 265 {
 266         int i;
 267
 268         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++)
 269                 if (efi_runtime_detach_list[i].ptr == p)
 270                         return true;
 271
 272         return false;
 273 }
 274
 275 static void efi_runtime_detach(ulong offset)
 276 {
 277         int i;
 278         ulong patchoff = offset - (ulong)gd->relocaddr;
 279
 280         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++) {
 281                 ulong patchto = (ulong)efi_runtime_detach_list[i].patchto;
 282                 ulong *p = efi_runtime_detach_list[i].ptr;
 283                 ulong newaddr = patchto ? (patchto + patchoff) : 0;
 284
 285                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 286                 *p = newaddr;
 287         }
 288
 289         /* Update crc32 */
 290         efi_update_table_header_crc32(&efi_runtime_services.hdr);
 291 }
 292
 293 /* Relocate EFI runtime to uboot_reloc_base = offset */
 294 void efi_runtime_relocate(ulong offset, struct efi_mem_desc *map)
 295 {
 296 #ifdef IS_RELA
 297         struct elf_rela *rel = (void*)&__efi_runtime_rel_start;
 298 #else
 299         struct elf_rel *rel = (void*)&__efi_runtime_rel_start;
 300         static ulong lastoff = CONFIG_SYS_TEXT_BASE;
 301 #endif
 302
 303         debug("%s: Relocating to offset=%lx\n", __func__, offset);
 304         for (; (ulong)rel < (ulong)&__efi_runtime_rel_stop; rel++) {
 305                 ulong base = CONFIG_SYS_TEXT_BASE;
 306                 ulong *p;
 307                 ulong newaddr;
 308
 309                 p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
 310
 311                 debug("%s: rel->info=%#lx *p=%#lx rel->offset=%p\n", __func__, rel->info, *p, rel->offset);
 312
 313                 switch (rel->info & R_MASK) {
 314                 case R_RELATIVE:
 315 #ifdef IS_RELA
 316                 newaddr = rel->addend + offset - CONFIG_SYS_TEXT_BASE;
 317 #else
 318                 newaddr = *p - lastoff + offset;
 319 #endif
 320                         break;
 321 #ifdef R_ABSOLUTE
 322                 case R_ABSOLUTE: {
 323                         ulong symidx = rel->info >> SYM_INDEX;
 324                         extern struct dyn_sym __dyn_sym_start[];
 325                         newaddr = __dyn_sym_start[symidx].addr + offset;
 326                         break;
 327                 }
 328 #endif
 329                 default:
 330                         continue;
 331                 }
 332
 333                 /* Check if the relocation is inside bounds */
 334                 if (map && ((newaddr < map->virtual_start) ||
 335                     newaddr > (map->virtual_start +
 336                               (map->num_pages << EFI_PAGE_SHIFT)))) {
 337                         if (!efi_runtime_tobedetached(p))
 338                                 printf("U-Boot EFI: Relocation at %p is out of "
 339                                        "range (%lx)\n", p, newaddr);
 340                         continue;
 341                 }
 342
 343                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 344                 *p = newaddr;
 345                 flush_dcache_range((ulong)p & ~(EFI_CACHELINE_SIZE - 1),
 346                         ALIGN((ulong)&p[1], EFI_CACHELINE_SIZE));
 347         }
 348
 349 #ifndef IS_RELA
 350         lastoff = offset;
 351 #endif
 352
 353         invalidate_icache_all();
 354 }
 355
 356 static efi_status_t EFIAPI efi_set_virtual_address_map(
 357                         unsigned long memory_map_size,
 358                         unsigned long descriptor_size,
 359                         uint32_t descriptor_version,
 360                         struct efi_mem_desc *virtmap)
 361 {
 362         ulong runtime_start = (ulong)&__efi_runtime_start &
 363                               ~(ulong)EFI_PAGE_MASK;
 364         int n = memory_map_size / descriptor_size;
 365         int i;
 366
 367         EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
 368                   descriptor_version, virtmap);
 369
 370         /* Rebind mmio pointers */
 371         for (i = 0; i < n; i++) {
 372                 struct efi_mem_desc *map = (void*)virtmap +
 373                                            (descriptor_size * i);
 374                 struct list_head *lhandle;
 375                 efi_physical_addr_t map_start = map->physical_start;
 376                 efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
 377                 efi_physical_addr_t map_end = map_start + map_len;
 378                 u64 off = map->virtual_start - map_start;
 379
 380                 /* Adjust all mmio pointers in this region */
 381                 list_for_each(lhandle, &efi_runtime_mmio) {
 382                         struct efi_runtime_mmio_list *lmmio;
 383
 384                         lmmio = list_entry(lhandle,
 385                                            struct efi_runtime_mmio_list,
 386                                            link);
 387                         if ((map_start <= lmmio->paddr) &&
 388                             (map_end >= lmmio->paddr)) {
 389                                 uintptr_t new_addr = lmmio->paddr + off;
 390                                 *lmmio->ptr = (void *)new_addr;
 391                         }
 392                 }
 393                 if ((map_start <= (uintptr_t)systab.tables) &&
 394                     (map_end >= (uintptr_t)systab.tables)) {
 395                         char *ptr = (char *)systab.tables;
 396
 397                         ptr += off;
 398                         systab.tables = (struct efi_configuration_table *)ptr;
 399                 }
 400         }
 401
 402         /* Move the actual runtime code over */
 403         for (i = 0; i < n; i++) {
 404                 struct efi_mem_desc *map;
 405
 406                 map = (void*)virtmap + (descriptor_size * i);
 407                 if (map->type == EFI_RUNTIME_SERVICES_CODE) {
 408                         ulong new_offset = map->virtual_start -
 409                                            (runtime_start - gd->relocaddr);
 410
 411                         efi_runtime_relocate(new_offset, map);
 412                         /* Once we're virtual, we can no longer handle
 413                            complex callbacks */
 414                         efi_runtime_detach(new_offset);
 415                         return EFI_EXIT(EFI_SUCCESS);
 416                 }
 417         }
 418
 419         return EFI_EXIT(EFI_INVALID_PARAMETER);
 420 }
 421
 422 efi_status_t efi_add_runtime_mmio(void *mmio_ptr, u64 len)
 423 {
 424         struct efi_runtime_mmio_list *newmmio;
 425         u64 pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
 426         uint64_t addr = *(uintptr_t *)mmio_ptr;
 427         uint64_t retaddr;
 428
 429         retaddr = efi_add_memory_map(addr, pages, EFI_MMAP_IO, false);
 430         if (retaddr != addr)
 431                 return EFI_OUT_OF_RESOURCES;
 432
 433         newmmio = calloc(1, sizeof(*newmmio));
 434         if (!newmmio)
 435                 return EFI_OUT_OF_RESOURCES;
 436         newmmio->ptr = mmio_ptr;
 437         newmmio->paddr = *(uintptr_t *)mmio_ptr;
 438         newmmio->len = len;
 439         list_add_tail(&newmmio->link, &efi_runtime_mmio);
 440
 441         return EFI_SUCCESS;
 442 }
 443
 444 /*
 445  * In the second stage, U-Boot has disappeared. To isolate our runtime code
 446  * that at this point still exists from the rest, we put it into a special
 447  * section.
 448  *
 449  *        !!WARNING!!
 450  *
 451  * This means that we can not rely on any code outside of this file in any
 452  * function or variable below this line.
 453  *
 454  * Please keep everything fully self-contained and annotated with
 455  * __efi_runtime and __efi_runtime_data markers.
 456  */
 457
 458 /*
 459  * Relocate the EFI runtime stub to a different place. We need to call this
 460  * the first time we expose the runtime interface to a user and on set virtual
 461  * address map calls.
 462  */
 463
 464 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void)
 465 {
 466         return EFI_UNSUPPORTED;
 467 }
 468
 469 static efi_status_t __efi_runtime EFIAPI efi_device_error(void)
 470 {
 471         return EFI_DEVICE_ERROR;
 472 }
 473
 474 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void)
 475 {
 476         return EFI_INVALID_PARAMETER;
 477 }
 478
 479 efi_status_t __efi_runtime EFIAPI efi_update_capsule(
 480                         struct efi_capsule_header **capsule_header_array,
 481                         efi_uintn_t capsule_count,
 482                         u64 scatter_gather_list)
 483 {
 484         return EFI_UNSUPPORTED;
 485 }
 486
 487 efi_status_t __efi_runtime EFIAPI efi_query_capsule_caps(
 488                         struct efi_capsule_header **capsule_header_array,
 489                         efi_uintn_t capsule_count,
 490                         u64 maximum_capsule_size,
 491                         u32 reset_type)
 492 {
 493         return EFI_UNSUPPORTED;
 494 }
 495
 496 efi_status_t __efi_runtime EFIAPI efi_query_variable_info(
 497                         u32 attributes,
 498                         u64 *maximum_variable_storage_size,
 499                         u64 *remaining_variable_storage_size,
 500                         u64 *maximum_variable_size)
 501 {
 502         return EFI_UNSUPPORTED;
 503 }
 504
 505 struct efi_runtime_services __efi_runtime_data efi_runtime_services = {
 506         .hdr = {
 507                 .signature = EFI_RUNTIME_SERVICES_SIGNATURE,
 508                 .revision = EFI_SPECIFICATION_VERSION,
 509                 .headersize = sizeof(struct efi_runtime_services),
 510         },
 511         .get_time = &efi_get_time_boottime,
 512         .set_time = (void *)&efi_device_error,
 513         .get_wakeup_time = (void *)&efi_unimplemented,
 514         .set_wakeup_time = (void *)&efi_unimplemented,
 515         .set_virtual_address_map = &efi_set_virtual_address_map,
 516         .convert_pointer = (void *)&efi_invalid_parameter,
 517         .get_variable = efi_get_variable,
 518         .get_next_variable_name = efi_get_next_variable_name,
 519         .set_variable = efi_set_variable,
 520         .get_next_high_mono_count = (void *)&efi_device_error,
 521         .reset_system = &efi_reset_system_boottime,
 522         .update_capsule = efi_update_capsule,
 523         .query_capsule_caps = efi_query_capsule_caps,
 524         .query_variable_info = efi_query_variable_info,
 525 };