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