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