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(__aarch64__)
  36 #define R_RELATIVE      1027
  37 #define R_MASK          0xffffffffULL
  38 #define IS_RELA         1
  39 #elif defined(__arm__)
  40 #define R_RELATIVE      23
  41 #define R_MASK          0xffULL
  42 #elif defined(__x86_64__) || defined(__i386__)
  43 #include <asm/elf.h>
  44 #define R_RELATIVE      R_386_RELATIVE
  45 #define R_MASK          0xffULL
  46 #elif defined(__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 #if (__riscv_xlen == 32)
  59 #define R_ABSOLUTE      R_RISCV_32
  60 #define SYM_INDEX       8
  61 #elif (__riscv_xlen == 64)
  62 #define R_ABSOLUTE      R_RISCV_64
  63 #define SYM_INDEX       32
  64 #else
  65 #error unknown riscv target
  66 #endif
  67 #else
  68 #error Need to add relocation awareness
  69 #endif
  70
  71 struct elf_rel {
  72         ulong *offset;
  73         ulong info;
  74 };
  75
  76 struct elf_rela {
  77         ulong *offset;
  78         ulong info;
  79         long addend;
  80 };
  81
  82 /*
  83  * EFI Runtime code lives in 2 stages. In the first stage, U-Boot and an EFI
  84  * payload are running concurrently at the same time. In this mode, we can
  85  * handle a good number of runtime callbacks
  86  */
  87
  88 static void EFIAPI efi_reset_system_boottime(
  89                         enum efi_reset_type reset_type,
  90                         efi_status_t reset_status,
  91                         unsigned long data_size, void *reset_data)
  92 {
  93         struct efi_event *evt;
  94
  95         EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
  96                   reset_data);
  97
  98         /* Notify reset */
  99         list_for_each_entry(evt, &efi_events, link) {
 100                 if (evt->group &&
 101                     !guidcmp(evt->group,
 102                              &efi_guid_event_group_reset_system)) {
 103                         efi_signal_event(evt, false);
 104                         break;
 105                 }
 106         }
 107         switch (reset_type) {
 108         case EFI_RESET_COLD:
 109         case EFI_RESET_WARM:
 110         case EFI_RESET_PLATFORM_SPECIFIC:
 111                 do_reset(NULL, 0, 0, NULL);
 112                 break;
 113         case EFI_RESET_SHUTDOWN:
 114                 /* We don't have anything to map this to */
 115                 break;
 116         }
 117
 118         while (1) { }
 119 }
 120
 121 static efi_status_t EFIAPI efi_get_time_boottime(
 122                         struct efi_time *time,
 123                         struct efi_time_cap *capabilities)
 124 {
 125 #if defined(CONFIG_CMD_DATE) && defined(CONFIG_DM_RTC)
 126         struct rtc_time tm;
 127         int r;
 128         struct udevice *dev;
 129
 130         EFI_ENTRY("%p %p", time, capabilities);
 131
 132         r = uclass_get_device(UCLASS_RTC, 0, &dev);
 133         if (r)
 134                 return EFI_EXIT(EFI_DEVICE_ERROR);
 135
 136         r = dm_rtc_get(dev, &tm);
 137         if (r)
 138                 return EFI_EXIT(EFI_DEVICE_ERROR);
 139
 140         memset(time, 0, sizeof(*time));
 141         time->year = tm.tm_year;
 142         time->month = tm.tm_mon;
 143         time->day = tm.tm_mday;
 144         time->hour = tm.tm_hour;
 145         time->minute = tm.tm_min;
 146         time->daylight = tm.tm_isdst;
 147
 148         return EFI_EXIT(EFI_SUCCESS);
 149 #else
 150         return EFI_DEVICE_ERROR;
 151 #endif
 152 }
 153
 154 /* Boards may override the helpers below to implement RTS functionality */
 155
 156 void __weak __efi_runtime EFIAPI efi_reset_system(
 157                         enum efi_reset_type reset_type,
 158                         efi_status_t reset_status,
 159                         unsigned long data_size, void *reset_data)
 160 {
 161         /* Nothing we can do */
 162         while (1) { }
 163 }
 164
 165 efi_status_t __weak efi_reset_system_init(void)
 166 {
 167         return EFI_SUCCESS;
 168 }
 169
 170 efi_status_t __weak __efi_runtime EFIAPI efi_get_time(
 171                         struct efi_time *time,
 172                         struct efi_time_cap *capabilities)
 173 {
 174         /* Nothing we can do */
 175         return EFI_DEVICE_ERROR;
 176 }
 177
 178 efi_status_t __weak efi_get_time_init(void)
 179 {
 180         return EFI_SUCCESS;
 181 }
 182
 183 struct efi_runtime_detach_list_struct {
 184         void *ptr;
 185         void *patchto;
 186 };
 187
 188 static const struct efi_runtime_detach_list_struct efi_runtime_detach_list[] = {
 189         {
 190                 /* do_reset is gone */
 191                 .ptr = &efi_runtime_services.reset_system,
 192                 .patchto = efi_reset_system,
 193         }, {
 194                 /* invalidate_*cache_all are gone */
 195                 .ptr = &efi_runtime_services.set_virtual_address_map,
 196                 .patchto = &efi_invalid_parameter,
 197         }, {
 198                 /* RTC accessors are gone */
 199                 .ptr = &efi_runtime_services.get_time,
 200                 .patchto = &efi_get_time,
 201         }, {
 202                 /* Clean up system table */
 203                 .ptr = &systab.con_in,
 204                 .patchto = NULL,
 205         }, {
 206                 /* Clean up system table */
 207                 .ptr = &systab.con_out,
 208                 .patchto = NULL,
 209         }, {
 210                 /* Clean up system table */
 211                 .ptr = &systab.std_err,
 212                 .patchto = NULL,
 213         }, {
 214                 /* Clean up system table */
 215                 .ptr = &systab.boottime,
 216                 .patchto = NULL,
 217         }, {
 218                 .ptr = &efi_runtime_services.get_variable,
 219                 .patchto = &efi_device_error,
 220         }, {
 221                 .ptr = &efi_runtime_services.get_next_variable_name,
 222                 .patchto = &efi_device_error,
 223         }, {
 224                 .ptr = &efi_runtime_services.set_variable,
 225                 .patchto = &efi_device_error,
 226         }
 227 };
 228
 229 static bool efi_runtime_tobedetached(void *p)
 230 {
 231         int i;
 232
 233         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++)
 234                 if (efi_runtime_detach_list[i].ptr == p)
 235                         return true;
 236
 237         return false;
 238 }
 239
 240 static void efi_runtime_detach(ulong offset)
 241 {
 242         int i;
 243         ulong patchoff = offset - (ulong)gd->relocaddr;
 244
 245         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++) {
 246                 ulong patchto = (ulong)efi_runtime_detach_list[i].patchto;
 247                 ulong *p = efi_runtime_detach_list[i].ptr;
 248                 ulong newaddr = patchto ? (patchto + patchoff) : 0;
 249
 250                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 251                 *p = newaddr;
 252         }
 253 }
 254
 255 /* Relocate EFI runtime to uboot_reloc_base = offset */
 256 void efi_runtime_relocate(ulong offset, struct efi_mem_desc *map)
 257 {
 258 #ifdef IS_RELA
 259         struct elf_rela *rel = (void*)&__efi_runtime_rel_start;
 260 #else
 261         struct elf_rel *rel = (void*)&__efi_runtime_rel_start;
 262         static ulong lastoff = CONFIG_SYS_TEXT_BASE;
 263 #endif
 264
 265         debug("%s: Relocating to offset=%lx\n", __func__, offset);
 266         for (; (ulong)rel < (ulong)&__efi_runtime_rel_stop; rel++) {
 267                 ulong base = CONFIG_SYS_TEXT_BASE;
 268                 ulong *p;
 269                 ulong newaddr;
 270
 271                 p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
 272
 273                 debug("%s: rel->info=%#lx *p=%#lx rel->offset=%p\n", __func__, rel->info, *p, rel->offset);
 274
 275                 switch (rel->info & R_MASK) {
 276                 case R_RELATIVE:
 277 #ifdef IS_RELA
 278                 newaddr = rel->addend + offset - CONFIG_SYS_TEXT_BASE;
 279 #else
 280                 newaddr = *p - lastoff + offset;
 281 #endif
 282                         break;
 283 #ifdef R_ABSOLUTE
 284                 case R_ABSOLUTE: {
 285                         ulong symidx = rel->info >> SYM_INDEX;
 286                         extern struct dyn_sym __dyn_sym_start[];
 287                         newaddr = __dyn_sym_start[symidx].addr + offset;
 288                         break;
 289                 }
 290 #endif
 291                 default:
 292                         continue;
 293                 }
 294
 295                 /* Check if the relocation is inside bounds */
 296                 if (map && ((newaddr < map->virtual_start) ||
 297                     newaddr > (map->virtual_start +
 298                               (map->num_pages << EFI_PAGE_SHIFT)))) {
 299                         if (!efi_runtime_tobedetached(p))
 300                                 printf("U-Boot EFI: Relocation at %p is out of "
 301                                        "range (%lx)\n", p, newaddr);
 302                         continue;
 303                 }
 304
 305                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 306                 *p = newaddr;
 307                 flush_dcache_range((ulong)p & ~(EFI_CACHELINE_SIZE - 1),
 308                         ALIGN((ulong)&p[1], EFI_CACHELINE_SIZE));
 309         }
 310
 311 #ifndef IS_RELA
 312         lastoff = offset;
 313 #endif
 314
 315         invalidate_icache_all();
 316 }
 317
 318 static efi_status_t EFIAPI efi_set_virtual_address_map(
 319                         unsigned long memory_map_size,
 320                         unsigned long descriptor_size,
 321                         uint32_t descriptor_version,
 322                         struct efi_mem_desc *virtmap)
 323 {
 324         ulong runtime_start = (ulong)&__efi_runtime_start &
 325                               ~(ulong)EFI_PAGE_MASK;
 326         int n = memory_map_size / descriptor_size;
 327         int i;
 328
 329         EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
 330                   descriptor_version, virtmap);
 331
 332         /* Rebind mmio pointers */
 333         for (i = 0; i < n; i++) {
 334                 struct efi_mem_desc *map = (void*)virtmap +
 335                                            (descriptor_size * i);
 336                 struct list_head *lhandle;
 337                 efi_physical_addr_t map_start = map->physical_start;
 338                 efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
 339                 efi_physical_addr_t map_end = map_start + map_len;
 340
 341                 /* Adjust all mmio pointers in this region */
 342                 list_for_each(lhandle, &efi_runtime_mmio) {
 343                         struct efi_runtime_mmio_list *lmmio;
 344
 345                         lmmio = list_entry(lhandle,
 346                                            struct efi_runtime_mmio_list,
 347                                            link);
 348                         if ((map_start <= lmmio->paddr) &&
 349                             (map_end >= lmmio->paddr)) {
 350                                 u64 off = map->virtual_start - map_start;
 351                                 uintptr_t new_addr = lmmio->paddr + off;
 352                                 *lmmio->ptr = (void *)new_addr;
 353                         }
 354                 }
 355         }
 356
 357         /* Move the actual runtime code over */
 358         for (i = 0; i < n; i++) {
 359                 struct efi_mem_desc *map;
 360
 361                 map = (void*)virtmap + (descriptor_size * i);
 362                 if (map->type == EFI_RUNTIME_SERVICES_CODE) {
 363                         ulong new_offset = map->virtual_start -
 364                                            (runtime_start - gd->relocaddr);
 365
 366                         efi_runtime_relocate(new_offset, map);
 367                         /* Once we're virtual, we can no longer handle
 368                            complex callbacks */
 369                         efi_runtime_detach(new_offset);
 370                         return EFI_EXIT(EFI_SUCCESS);
 371                 }
 372         }
 373
 374         return EFI_EXIT(EFI_INVALID_PARAMETER);
 375 }
 376
 377 efi_status_t efi_add_runtime_mmio(void *mmio_ptr, u64 len)
 378 {
 379         struct efi_runtime_mmio_list *newmmio;
 380         u64 pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
 381         uint64_t addr = *(uintptr_t *)mmio_ptr;
 382         uint64_t retaddr;
 383
 384         retaddr = efi_add_memory_map(addr, pages, EFI_MMAP_IO, false);
 385         if (retaddr != addr)
 386                 return EFI_OUT_OF_RESOURCES;
 387
 388         newmmio = calloc(1, sizeof(*newmmio));
 389         if (!newmmio)
 390                 return EFI_OUT_OF_RESOURCES;
 391         newmmio->ptr = mmio_ptr;
 392         newmmio->paddr = *(uintptr_t *)mmio_ptr;
 393         newmmio->len = len;
 394         list_add_tail(&newmmio->link, &efi_runtime_mmio);
 395
 396         return EFI_SUCCESS;
 397 }
 398
 399 /*
 400  * In the second stage, U-Boot has disappeared. To isolate our runtime code
 401  * that at this point still exists from the rest, we put it into a special
 402  * section.
 403  *
 404  *        !!WARNING!!
 405  *
 406  * This means that we can not rely on any code outside of this file in any
 407  * function or variable below this line.
 408  *
 409  * Please keep everything fully self-contained and annotated with
 410  * __efi_runtime and __efi_runtime_data markers.
 411  */
 412
 413 /*
 414  * Relocate the EFI runtime stub to a different place. We need to call this
 415  * the first time we expose the runtime interface to a user and on set virtual
 416  * address map calls.
 417  */
 418
 419 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void)
 420 {
 421         return EFI_UNSUPPORTED;
 422 }
 423
 424 static efi_status_t __efi_runtime EFIAPI efi_device_error(void)
 425 {
 426         return EFI_DEVICE_ERROR;
 427 }
 428
 429 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void)
 430 {
 431         return EFI_INVALID_PARAMETER;
 432 }
 433
 434 efi_status_t __efi_runtime EFIAPI efi_update_capsule(
 435                         struct efi_capsule_header **capsule_header_array,
 436                         efi_uintn_t capsule_count,
 437                         u64 scatter_gather_list)
 438 {
 439         return EFI_UNSUPPORTED;
 440 }
 441
 442 efi_status_t __efi_runtime EFIAPI efi_query_capsule_caps(
 443                         struct efi_capsule_header **capsule_header_array,
 444                         efi_uintn_t capsule_count,
 445                         u64 maximum_capsule_size,
 446                         u32 reset_type)
 447 {
 448         return EFI_UNSUPPORTED;
 449 }
 450
 451 efi_status_t __efi_runtime EFIAPI efi_query_variable_info(
 452                         u32 attributes,
 453                         u64 *maximum_variable_storage_size,
 454                         u64 *remaining_variable_storage_size,
 455                         u64 *maximum_variable_size)
 456 {
 457         return EFI_UNSUPPORTED;
 458 }
 459
 460 struct efi_runtime_services __efi_runtime_data efi_runtime_services = {
 461         .hdr = {
 462                 .signature = EFI_RUNTIME_SERVICES_SIGNATURE,
 463                 .revision = EFI_RUNTIME_SERVICES_REVISION,
 464                 .headersize = sizeof(struct efi_table_hdr),
 465         },
 466         .get_time = &efi_get_time_boottime,
 467         .set_time = (void *)&efi_device_error,
 468         .get_wakeup_time = (void *)&efi_unimplemented,
 469         .set_wakeup_time = (void *)&efi_unimplemented,
 470         .set_virtual_address_map = &efi_set_virtual_address_map,
 471         .convert_pointer = (void *)&efi_invalid_parameter,
 472         .get_variable = efi_get_variable,
 473         .get_next_variable_name = efi_get_next_variable_name,
 474         .set_variable = efi_set_variable,
 475         .get_next_high_mono_count = (void *)&efi_device_error,
 476         .reset_system = &efi_reset_system_boottime,
 477         .update_capsule = efi_update_capsule,
 478         .query_capsule_caps = efi_query_capsule_caps,
 479         .query_variable_info = efi_query_variable_info,
 480 };