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