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