lib/efi_loader/efi_runtime.c

   1 /*
   2  *  EFI application runtime services
   3  *
   4  *  Copyright (c) 2016 Alexander Graf
   5  *
   6  *  SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <command.h>
  11 #include <dm.h>
  12 #include <efi_loader.h>
  13 #include <rtc.h>
  14 #include <asm/global_data.h>
  15
  16 /* For manual relocation support */
  17 DECLARE_GLOBAL_DATA_PTR;
  18
  19 struct efi_runtime_mmio_list {
  20         struct list_head link;
  21         void **ptr;
  22         u64 paddr;
  23         u64 len;
  24 };
  25
  26 /* This list contains all runtime available mmio regions */
  27 LIST_HEAD(efi_runtime_mmio);
  28
  29 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void);
  30 static efi_status_t __efi_runtime EFIAPI efi_device_error(void);
  31 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void);
  32
  33 #ifdef CONFIG_SYS_CACHELINE_SIZE
  34 #define EFI_CACHELINE_SIZE CONFIG_SYS_CACHELINE_SIZE
  35 #else
  36 /* Just use the greatest cache flush alignment requirement I'm aware of */
  37 #define EFI_CACHELINE_SIZE 128
  38 #endif
  39
  40 #if defined(CONFIG_ARM64)
  41 #define R_RELATIVE      1027
  42 #define R_MASK          0xffffffffULL
  43 #define IS_RELA         1
  44 #elif defined(CONFIG_ARM)
  45 #define R_RELATIVE      23
  46 #define R_MASK          0xffULL
  47 #elif defined(CONFIG_X86)
  48 #include <asm/elf.h>
  49 #define R_RELATIVE      R_386_RELATIVE
  50 #define R_MASK          0xffULL
  51 #else
  52 #error Need to add relocation awareness
  53 #endif
  54
  55 struct elf_rel {
  56         ulong *offset;
  57         ulong info;
  58 };
  59
  60 struct elf_rela {
  61         ulong *offset;
  62         ulong info;
  63         long addend;
  64 };
  65
  66 /*
  67  * EFI Runtime code lives in 2 stages. In the first stage, U-Boot and an EFI
  68  * payload are running concurrently at the same time. In this mode, we can
  69  * handle a good number of runtime callbacks
  70  */
  71
  72 static void EFIAPI efi_reset_system_boottime(
  73                         enum efi_reset_type reset_type,
  74                         efi_status_t reset_status,
  75                         unsigned long data_size, void *reset_data)
  76 {
  77         struct efi_event *evt;
  78
  79         EFI_ENTRY("%d %lx %lx %p", reset_type, reset_status, data_size,
  80                   reset_data);
  81
  82         /* Notify reset */
  83         list_for_each_entry(evt, &efi_events, link) {
  84                 if (evt->group &&
  85                     !guidcmp(evt->group,
  86                              &efi_guid_event_group_reset_system)) {
  87                         efi_signal_event(evt, false);
  88                         break;
  89                 }
  90         }
  91         switch (reset_type) {
  92         case EFI_RESET_COLD:
  93         case EFI_RESET_WARM:
  94                 do_reset(NULL, 0, 0, NULL);
  95                 break;
  96         case EFI_RESET_SHUTDOWN:
  97                 /* We don't have anything to map this to */
  98                 break;
  99         }
 100
 101         while (1) { }
 102 }
 103
 104 static efi_status_t EFIAPI efi_get_time_boottime(
 105                         struct efi_time *time,
 106                         struct efi_time_cap *capabilities)
 107 {
 108 #if defined(CONFIG_CMD_DATE) && defined(CONFIG_DM_RTC)
 109         struct rtc_time tm;
 110         int r;
 111         struct udevice *dev;
 112
 113         EFI_ENTRY("%p %p", time, capabilities);
 114
 115         r = uclass_get_device(UCLASS_RTC, 0, &dev);
 116         if (r)
 117                 return EFI_EXIT(EFI_DEVICE_ERROR);
 118
 119         r = dm_rtc_get(dev, &tm);
 120         if (r)
 121                 return EFI_EXIT(EFI_DEVICE_ERROR);
 122
 123         memset(time, 0, sizeof(*time));
 124         time->year = tm.tm_year;
 125         time->month = tm.tm_mon;
 126         time->day = tm.tm_mday;
 127         time->hour = tm.tm_hour;
 128         time->minute = tm.tm_min;
 129         time->daylight = tm.tm_isdst;
 130
 131         return EFI_EXIT(EFI_SUCCESS);
 132 #else
 133         return EFI_DEVICE_ERROR;
 134 #endif
 135 }
 136
 137 /* Boards may override the helpers below to implement RTS functionality */
 138
 139 void __weak __efi_runtime EFIAPI efi_reset_system(
 140                         enum efi_reset_type reset_type,
 141                         efi_status_t reset_status,
 142                         unsigned long data_size, void *reset_data)
 143 {
 144         /* Nothing we can do */
 145         while (1) { }
 146 }
 147
 148 efi_status_t __weak efi_reset_system_init(void)
 149 {
 150         return EFI_SUCCESS;
 151 }
 152
 153 efi_status_t __weak __efi_runtime EFIAPI efi_get_time(
 154                         struct efi_time *time,
 155                         struct efi_time_cap *capabilities)
 156 {
 157         /* Nothing we can do */
 158         return EFI_DEVICE_ERROR;
 159 }
 160
 161 efi_status_t __weak efi_get_time_init(void)
 162 {
 163         return EFI_SUCCESS;
 164 }
 165
 166 struct efi_runtime_detach_list_struct {
 167         void *ptr;
 168         void *patchto;
 169 };
 170
 171 static const struct efi_runtime_detach_list_struct efi_runtime_detach_list[] = {
 172         {
 173                 /* do_reset is gone */
 174                 .ptr = &efi_runtime_services.reset_system,
 175                 .patchto = efi_reset_system,
 176         }, {
 177                 /* invalidate_*cache_all are gone */
 178                 .ptr = &efi_runtime_services.set_virtual_address_map,
 179                 .patchto = &efi_invalid_parameter,
 180         }, {
 181                 /* RTC accessors are gone */
 182                 .ptr = &efi_runtime_services.get_time,
 183                 .patchto = &efi_get_time,
 184         }, {
 185                 /* Clean up system table */
 186                 .ptr = &systab.con_in,
 187                 .patchto = NULL,
 188         }, {
 189                 /* Clean up system table */
 190                 .ptr = &systab.con_out,
 191                 .patchto = NULL,
 192         }, {
 193                 /* Clean up system table */
 194                 .ptr = &systab.std_err,
 195                 .patchto = NULL,
 196         }, {
 197                 /* Clean up system table */
 198                 .ptr = &systab.boottime,
 199                 .patchto = NULL,
 200         }, {
 201                 .ptr = &efi_runtime_services.get_variable,
 202                 .patchto = &efi_device_error,
 203         }, {
 204                 .ptr = &efi_runtime_services.get_next_variable,
 205                 .patchto = &efi_device_error,
 206         }, {
 207                 .ptr = &efi_runtime_services.set_variable,
 208                 .patchto = &efi_device_error,
 209         }
 210 };
 211
 212 static bool efi_runtime_tobedetached(void *p)
 213 {
 214         int i;
 215
 216         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++)
 217                 if (efi_runtime_detach_list[i].ptr == p)
 218                         return true;
 219
 220         return false;
 221 }
 222
 223 static void efi_runtime_detach(ulong offset)
 224 {
 225         int i;
 226         ulong patchoff = offset - (ulong)gd->relocaddr;
 227
 228         for (i = 0; i < ARRAY_SIZE(efi_runtime_detach_list); i++) {
 229                 ulong patchto = (ulong)efi_runtime_detach_list[i].patchto;
 230                 ulong *p = efi_runtime_detach_list[i].ptr;
 231                 ulong newaddr = patchto ? (patchto + patchoff) : 0;
 232
 233                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 234                 *p = newaddr;
 235         }
 236 }
 237
 238 /* Relocate EFI runtime to uboot_reloc_base = offset */
 239 void efi_runtime_relocate(ulong offset, struct efi_mem_desc *map)
 240 {
 241 #ifdef IS_RELA
 242         struct elf_rela *rel = (void*)&__efi_runtime_rel_start;
 243 #else
 244         struct elf_rel *rel = (void*)&__efi_runtime_rel_start;
 245         static ulong lastoff = CONFIG_SYS_TEXT_BASE;
 246 #endif
 247
 248         debug("%s: Relocating to offset=%lx\n", __func__, offset);
 249         for (; (ulong)rel < (ulong)&__efi_runtime_rel_stop; rel++) {
 250                 ulong base = CONFIG_SYS_TEXT_BASE;
 251                 ulong *p;
 252                 ulong newaddr;
 253
 254                 p = (void*)((ulong)rel->offset - base) + gd->relocaddr;
 255
 256                 if ((rel->info & R_MASK) != R_RELATIVE) {
 257                         continue;
 258                 }
 259
 260 #ifdef IS_RELA
 261                 newaddr = rel->addend + offset - CONFIG_SYS_TEXT_BASE;
 262 #else
 263                 newaddr = *p - lastoff + offset;
 264 #endif
 265
 266                 /* Check if the relocation is inside bounds */
 267                 if (map && ((newaddr < map->virtual_start) ||
 268                     newaddr > (map->virtual_start +
 269                               (map->num_pages << EFI_PAGE_SHIFT)))) {
 270                         if (!efi_runtime_tobedetached(p))
 271                                 printf("U-Boot EFI: Relocation at %p is out of "
 272                                        "range (%lx)\n", p, newaddr);
 273                         continue;
 274                 }
 275
 276                 debug("%s: Setting %p to %lx\n", __func__, p, newaddr);
 277                 *p = newaddr;
 278                 flush_dcache_range((ulong)p & ~(EFI_CACHELINE_SIZE - 1),
 279                         ALIGN((ulong)&p[1], EFI_CACHELINE_SIZE));
 280         }
 281
 282 #ifndef IS_RELA
 283         lastoff = offset;
 284 #endif
 285
 286         invalidate_icache_all();
 287 }
 288
 289 static efi_status_t EFIAPI efi_set_virtual_address_map(
 290                         unsigned long memory_map_size,
 291                         unsigned long descriptor_size,
 292                         uint32_t descriptor_version,
 293                         struct efi_mem_desc *virtmap)
 294 {
 295         ulong runtime_start = (ulong)&__efi_runtime_start &
 296                               ~(ulong)EFI_PAGE_MASK;
 297         int n = memory_map_size / descriptor_size;
 298         int i;
 299
 300         EFI_ENTRY("%lx %lx %x %p", memory_map_size, descriptor_size,
 301                   descriptor_version, virtmap);
 302
 303         /* Rebind mmio pointers */
 304         for (i = 0; i < n; i++) {
 305                 struct efi_mem_desc *map = (void*)virtmap +
 306                                            (descriptor_size * i);
 307                 struct list_head *lhandle;
 308                 efi_physical_addr_t map_start = map->physical_start;
 309                 efi_physical_addr_t map_len = map->num_pages << EFI_PAGE_SHIFT;
 310                 efi_physical_addr_t map_end = map_start + map_len;
 311
 312                 /* Adjust all mmio pointers in this region */
 313                 list_for_each(lhandle, &efi_runtime_mmio) {
 314                         struct efi_runtime_mmio_list *lmmio;
 315
 316                         lmmio = list_entry(lhandle,
 317                                            struct efi_runtime_mmio_list,
 318                                            link);
 319                         if ((map_start <= lmmio->paddr) &&
 320                             (map_end >= lmmio->paddr)) {
 321                                 u64 off = map->virtual_start - map_start;
 322                                 uintptr_t new_addr = lmmio->paddr + off;
 323                                 *lmmio->ptr = (void *)new_addr;
 324                         }
 325                 }
 326         }
 327
 328         /* Move the actual runtime code over */
 329         for (i = 0; i < n; i++) {
 330                 struct efi_mem_desc *map;
 331
 332                 map = (void*)virtmap + (descriptor_size * i);
 333                 if (map->type == EFI_RUNTIME_SERVICES_CODE) {
 334                         ulong new_offset = map->virtual_start -
 335                                            (runtime_start - gd->relocaddr);
 336
 337                         efi_runtime_relocate(new_offset, map);
 338                         /* Once we're virtual, we can no longer handle
 339                            complex callbacks */
 340                         efi_runtime_detach(new_offset);
 341                         return EFI_EXIT(EFI_SUCCESS);
 342                 }
 343         }
 344
 345         return EFI_EXIT(EFI_INVALID_PARAMETER);
 346 }
 347
 348 efi_status_t efi_add_runtime_mmio(void *mmio_ptr, u64 len)
 349 {
 350         struct efi_runtime_mmio_list *newmmio;
 351         efi_status_t ret;
 352
 353         u64 pages = (len + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT;
 354         ret = efi_add_memory_map(*(uintptr_t *)mmio_ptr, pages, EFI_MMAP_IO,
 355                                  false);
 356         if (ret != EFI_SUCCESS)
 357                 return ret;
 358
 359         newmmio = calloc(1, sizeof(*newmmio));
 360         if (!newmmio)
 361                 return EFI_OUT_OF_RESOURCES;
 362         newmmio->ptr = mmio_ptr;
 363         newmmio->paddr = *(uintptr_t *)mmio_ptr;
 364         newmmio->len = len;
 365         list_add_tail(&newmmio->link, &efi_runtime_mmio);
 366
 367         return ret;
 368 }
 369
 370 /*
 371  * In the second stage, U-Boot has disappeared. To isolate our runtime code
 372  * that at this point still exists from the rest, we put it into a special
 373  * section.
 374  *
 375  *        !!WARNING!!
 376  *
 377  * This means that we can not rely on any code outside of this file in any
 378  * function or variable below this line.
 379  *
 380  * Please keep everything fully self-contained and annotated with
 381  * __efi_runtime and __efi_runtime_data markers.
 382  */
 383
 384 /*
 385  * Relocate the EFI runtime stub to a different place. We need to call this
 386  * the first time we expose the runtime interface to a user and on set virtual
 387  * address map calls.
 388  */
 389
 390 static efi_status_t __efi_runtime EFIAPI efi_unimplemented(void)
 391 {
 392         return EFI_UNSUPPORTED;
 393 }
 394
 395 static efi_status_t __efi_runtime EFIAPI efi_device_error(void)
 396 {
 397         return EFI_DEVICE_ERROR;
 398 }
 399
 400 static efi_status_t __efi_runtime EFIAPI efi_invalid_parameter(void)
 401 {
 402         return EFI_INVALID_PARAMETER;
 403 }
 404
 405 efi_status_t __efi_runtime EFIAPI efi_update_capsule(
 406                         struct efi_capsule_header **capsule_header_array,
 407                         efi_uintn_t capsule_count,
 408                         u64 scatter_gather_list)
 409 {
 410         return EFI_UNSUPPORTED;
 411 }
 412
 413 efi_status_t __efi_runtime EFIAPI efi_query_capsule_caps(
 414                         struct efi_capsule_header **capsule_header_array,
 415                         efi_uintn_t capsule_count,
 416                         u64 maximum_capsule_size,
 417                         u32 reset_type)
 418 {
 419         return EFI_UNSUPPORTED;
 420 }
 421
 422 efi_status_t __efi_runtime EFIAPI efi_query_variable_info(
 423                         u32 attributes,
 424                         u64 maximum_variable_storage_size,
 425                         u64 remaining_variable_storage_size,
 426                         u64 maximum_variable_size)
 427 {
 428         return EFI_UNSUPPORTED;
 429 }
 430
 431 struct efi_runtime_services __efi_runtime_data efi_runtime_services = {
 432         .hdr = {
 433                 .signature = EFI_RUNTIME_SERVICES_SIGNATURE,
 434                 .revision = EFI_RUNTIME_SERVICES_REVISION,
 435                 .headersize = sizeof(struct efi_table_hdr),
 436         },
 437         .get_time = &efi_get_time_boottime,
 438         .set_time = (void *)&efi_device_error,
 439         .get_wakeup_time = (void *)&efi_unimplemented,
 440         .set_wakeup_time = (void *)&efi_unimplemented,
 441         .set_virtual_address_map = &efi_set_virtual_address_map,
 442         .convert_pointer = (void *)&efi_invalid_parameter,
 443         .get_variable = efi_get_variable,
 444         .get_next_variable = efi_get_next_variable,
 445         .set_variable = efi_set_variable,
 446         .get_next_high_mono_count = (void *)&efi_device_error,
 447         .reset_system = &efi_reset_system_boottime,
 448         .update_capsule = efi_update_capsule,
 449         .query_capsule_caps = efi_query_capsule_caps,
 450         .query_variable_info = efi_query_variable_info,
 451 };