git.sur5r.net Git - u-boot/blob - arch/arm/mach-imx/hab.c

   1 /*
   2  * Copyright (C) 2010-2015 Freescale Semiconductor, Inc.
   3  *
   4  * SPDX-License-Identifier:    GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <config.h>
   9 #include <fuse.h>
  10 #include <asm/io.h>
  11 #include <asm/system.h>
  12 #include <asm/arch/clock.h>
  13 #include <asm/arch/sys_proto.h>
  14 #include <asm/mach-imx/hab.h>
  15
  16 #define ALIGN_SIZE              0x1000
  17 #define MX6DQ_PU_IROM_MMU_EN_VAR        0x009024a8
  18 #define MX6DLS_PU_IROM_MMU_EN_VAR       0x00901dd0
  19 #define MX6SL_PU_IROM_MMU_EN_VAR        0x00900a18
  20 #define IS_HAB_ENABLED_BIT \
  21         (is_soc_type(MXC_SOC_MX7ULP) ? 0x80000000 :     \
  22          (is_soc_type(MXC_SOC_MX7) ? 0x2000000 : 0x2))
  23
  24 static int ivt_header_error(const char *err_str, struct ivt_header *ivt_hdr)
  25 {
  26         printf("%s magic=0x%x length=0x%02x version=0x%x\n", err_str,
  27                ivt_hdr->magic, ivt_hdr->length, ivt_hdr->version);
  28
  29         return 1;
  30 }
  31
  32 static int verify_ivt_header(struct ivt_header *ivt_hdr)
  33 {
  34         int result = 0;
  35
  36         if (ivt_hdr->magic != IVT_HEADER_MAGIC)
  37                 result = ivt_header_error("bad magic", ivt_hdr);
  38
  39         if (be16_to_cpu(ivt_hdr->length) != IVT_TOTAL_LENGTH)
  40                 result = ivt_header_error("bad length", ivt_hdr);
  41
  42         if (ivt_hdr->version != IVT_HEADER_V1 &&
  43             ivt_hdr->version != IVT_HEADER_V2)
  44                 result = ivt_header_error("bad version", ivt_hdr);
  45
  46         return result;
  47 }
  48
  49 #if !defined(CONFIG_SPL_BUILD)
  50
  51 #define MAX_RECORD_BYTES     (8*1024) /* 4 kbytes */
  52
  53 struct record {
  54         uint8_t  tag;                                           /* Tag */
  55         uint8_t  len[2];                                        /* Length */
  56         uint8_t  par;                                           /* Version */
  57         uint8_t  contents[MAX_RECORD_BYTES];/* Record Data */
  58         bool     any_rec_flag;
  59 };
  60
  61 static char *rsn_str[] = {
  62                           "RSN = HAB_RSN_ANY (0x00)\n",
  63                           "RSN = HAB_ENG_FAIL (0x30)\n",
  64                           "RSN = HAB_INV_ADDRESS (0x22)\n",
  65                           "RSN = HAB_INV_ASSERTION (0x0C)\n",
  66                           "RSN = HAB_INV_CALL (0x28)\n",
  67                           "RSN = HAB_INV_CERTIFICATE (0x21)\n",
  68                           "RSN = HAB_INV_COMMAND (0x06)\n",
  69                           "RSN = HAB_INV_CSF (0x11)\n",
  70                           "RSN = HAB_INV_DCD (0x27)\n",
  71                           "RSN = HAB_INV_INDEX (0x0F)\n",
  72                           "RSN = HAB_INV_IVT (0x05)\n",
  73                           "RSN = HAB_INV_KEY (0x1D)\n",
  74                           "RSN = HAB_INV_RETURN (0x1E)\n",
  75                           "RSN = HAB_INV_SIGNATURE (0x18)\n",
  76                           "RSN = HAB_INV_SIZE (0x17)\n",
  77                           "RSN = HAB_MEM_FAIL (0x2E)\n",
  78                           "RSN = HAB_OVR_COUNT (0x2B)\n",
  79                           "RSN = HAB_OVR_STORAGE (0x2D)\n",
  80                           "RSN = HAB_UNS_ALGORITHM (0x12)\n",
  81                           "RSN = HAB_UNS_COMMAND (0x03)\n",
  82                           "RSN = HAB_UNS_ENGINE (0x0A)\n",
  83                           "RSN = HAB_UNS_ITEM (0x24)\n",
  84                           "RSN = HAB_UNS_KEY (0x1B)\n",
  85                           "RSN = HAB_UNS_PROTOCOL (0x14)\n",
  86                           "RSN = HAB_UNS_STATE (0x09)\n",
  87                           "RSN = INVALID\n",
  88                           NULL
  89 };
  90
  91 static char *sts_str[] = {
  92                           "STS = HAB_SUCCESS (0xF0)\n",
  93                           "STS = HAB_FAILURE (0x33)\n",
  94                           "STS = HAB_WARNING (0x69)\n",
  95                           "STS = INVALID\n",
  96                           NULL
  97 };
  98
  99 static char *eng_str[] = {
 100                           "ENG = HAB_ENG_ANY (0x00)\n",
 101                           "ENG = HAB_ENG_SCC (0x03)\n",
 102                           "ENG = HAB_ENG_RTIC (0x05)\n",
 103                           "ENG = HAB_ENG_SAHARA (0x06)\n",
 104                           "ENG = HAB_ENG_CSU (0x0A)\n",
 105                           "ENG = HAB_ENG_SRTC (0x0C)\n",
 106                           "ENG = HAB_ENG_DCP (0x1B)\n",
 107                           "ENG = HAB_ENG_CAAM (0x1D)\n",
 108                           "ENG = HAB_ENG_SNVS (0x1E)\n",
 109                           "ENG = HAB_ENG_OCOTP (0x21)\n",
 110                           "ENG = HAB_ENG_DTCP (0x22)\n",
 111                           "ENG = HAB_ENG_ROM (0x36)\n",
 112                           "ENG = HAB_ENG_HDCP (0x24)\n",
 113                           "ENG = HAB_ENG_RTL (0x77)\n",
 114                           "ENG = HAB_ENG_SW (0xFF)\n",
 115                           "ENG = INVALID\n",
 116                           NULL
 117 };
 118
 119 static char *ctx_str[] = {
 120                           "CTX = HAB_CTX_ANY(0x00)\n",
 121                           "CTX = HAB_CTX_FAB (0xFF)\n",
 122                           "CTX = HAB_CTX_ENTRY (0xE1)\n",
 123                           "CTX = HAB_CTX_TARGET (0x33)\n",
 124                           "CTX = HAB_CTX_AUTHENTICATE (0x0A)\n",
 125                           "CTX = HAB_CTX_DCD (0xDD)\n",
 126                           "CTX = HAB_CTX_CSF (0xCF)\n",
 127                           "CTX = HAB_CTX_COMMAND (0xC0)\n",
 128                           "CTX = HAB_CTX_AUT_DAT (0xDB)\n",
 129                           "CTX = HAB_CTX_ASSERT (0xA0)\n",
 130                           "CTX = HAB_CTX_EXIT (0xEE)\n",
 131                           "CTX = INVALID\n",
 132                           NULL
 133 };
 134
 135 static uint8_t hab_statuses[5] = {
 136         HAB_STS_ANY,
 137         HAB_FAILURE,
 138         HAB_WARNING,
 139         HAB_SUCCESS,
 140         -1
 141 };
 142
 143 static uint8_t hab_reasons[26] = {
 144         HAB_RSN_ANY,
 145         HAB_ENG_FAIL,
 146         HAB_INV_ADDRESS,
 147         HAB_INV_ASSERTION,
 148         HAB_INV_CALL,
 149         HAB_INV_CERTIFICATE,
 150         HAB_INV_COMMAND,
 151         HAB_INV_CSF,
 152         HAB_INV_DCD,
 153         HAB_INV_INDEX,
 154         HAB_INV_IVT,
 155         HAB_INV_KEY,
 156         HAB_INV_RETURN,
 157         HAB_INV_SIGNATURE,
 158         HAB_INV_SIZE,
 159         HAB_MEM_FAIL,
 160         HAB_OVR_COUNT,
 161         HAB_OVR_STORAGE,
 162         HAB_UNS_ALGORITHM,
 163         HAB_UNS_COMMAND,
 164         HAB_UNS_ENGINE,
 165         HAB_UNS_ITEM,
 166         HAB_UNS_KEY,
 167         HAB_UNS_PROTOCOL,
 168         HAB_UNS_STATE,
 169         -1
 170 };
 171
 172 static uint8_t hab_contexts[12] = {
 173         HAB_CTX_ANY,
 174         HAB_CTX_FAB,
 175         HAB_CTX_ENTRY,
 176         HAB_CTX_TARGET,
 177         HAB_CTX_AUTHENTICATE,
 178         HAB_CTX_DCD,
 179         HAB_CTX_CSF,
 180         HAB_CTX_COMMAND,
 181         HAB_CTX_AUT_DAT,
 182         HAB_CTX_ASSERT,
 183         HAB_CTX_EXIT,
 184         -1
 185 };
 186
 187 static uint8_t hab_engines[16] = {
 188         HAB_ENG_ANY,
 189         HAB_ENG_SCC,
 190         HAB_ENG_RTIC,
 191         HAB_ENG_SAHARA,
 192         HAB_ENG_CSU,
 193         HAB_ENG_SRTC,
 194         HAB_ENG_DCP,
 195         HAB_ENG_CAAM,
 196         HAB_ENG_SNVS,
 197         HAB_ENG_OCOTP,
 198         HAB_ENG_DTCP,
 199         HAB_ENG_ROM,
 200         HAB_ENG_HDCP,
 201         HAB_ENG_RTL,
 202         HAB_ENG_SW,
 203         -1
 204 };
 205
 206 static inline uint8_t get_idx(uint8_t *list, uint8_t tgt)
 207 {
 208         uint8_t idx = 0;
 209         uint8_t element = list[idx];
 210         while (element != -1) {
 211                 if (element == tgt)
 212                         return idx;
 213                 element = list[++idx];
 214         }
 215         return -1;
 216 }
 217
 218 static void process_event_record(uint8_t *event_data, size_t bytes)
 219 {
 220         struct record *rec = (struct record *)event_data;
 221
 222         printf("\n\n%s", sts_str[get_idx(hab_statuses, rec->contents[0])]);
 223         printf("%s", rsn_str[get_idx(hab_reasons, rec->contents[1])]);
 224         printf("%s", ctx_str[get_idx(hab_contexts, rec->contents[2])]);
 225         printf("%s", eng_str[get_idx(hab_engines, rec->contents[3])]);
 226 }
 227
 228 static void display_event(uint8_t *event_data, size_t bytes)
 229 {
 230         uint32_t i;
 231
 232         if (!(event_data && bytes > 0))
 233                 return;
 234
 235         for (i = 0; i < bytes; i++) {
 236                 if (i == 0)
 237                         printf("\t0x%02x", event_data[i]);
 238                 else if ((i % 8) == 0)
 239                         printf("\n\t0x%02x", event_data[i]);
 240                 else
 241                         printf(" 0x%02x", event_data[i]);
 242         }
 243
 244         process_event_record(event_data, bytes);
 245 }
 246
 247 static int get_hab_status(void)
 248 {
 249         uint32_t index = 0; /* Loop index */
 250         uint8_t event_data[128]; /* Event data buffer */
 251         size_t bytes = sizeof(event_data); /* Event size in bytes */
 252         enum hab_config config = 0;
 253         enum hab_state state = 0;
 254         hab_rvt_report_event_t *hab_rvt_report_event;
 255         hab_rvt_report_status_t *hab_rvt_report_status;
 256
 257         hab_rvt_report_event = (hab_rvt_report_event_t *)HAB_RVT_REPORT_EVENT;
 258         hab_rvt_report_status =
 259                         (hab_rvt_report_status_t *)HAB_RVT_REPORT_STATUS;
 260
 261         if (imx_hab_is_enabled())
 262                 puts("\nSecure boot enabled\n");
 263         else
 264                 puts("\nSecure boot disabled\n");
 265
 266         /* Check HAB status */
 267         if (hab_rvt_report_status(&config, &state) != HAB_SUCCESS) {
 268                 printf("\nHAB Configuration: 0x%02x, HAB State: 0x%02x\n",
 269                        config, state);
 270
 271                 /* Display HAB Error events */
 272                 while (hab_rvt_report_event(HAB_FAILURE, index, event_data,
 273                                         &bytes) == HAB_SUCCESS) {
 274                         puts("\n");
 275                         printf("--------- HAB Event %d -----------------\n",
 276                                index + 1);
 277                         puts("event data:\n");
 278                         display_event(event_data, bytes);
 279                         puts("\n");
 280                         bytes = sizeof(event_data);
 281                         index++;
 282                 }
 283         }
 284         /* Display message if no HAB events are found */
 285         else {
 286                 printf("\nHAB Configuration: 0x%02x, HAB State: 0x%02x\n",
 287                        config, state);
 288                 puts("No HAB Events Found!\n\n");
 289         }
 290         return 0;
 291 }
 292
 293 static int do_hab_status(cmd_tbl_t *cmdtp, int flag, int argc,
 294                          char * const argv[])
 295 {
 296         if ((argc != 1)) {
 297                 cmd_usage(cmdtp);
 298                 return 1;
 299         }
 300
 301         get_hab_status();
 302
 303         return 0;
 304 }
 305
 306 static int do_authenticate_image(cmd_tbl_t *cmdtp, int flag, int argc,
 307                                  char * const argv[])
 308 {
 309         ulong   addr, length, ivt_offset;
 310         int     rcode = 0;
 311
 312         if (argc < 4)
 313                 return CMD_RET_USAGE;
 314
 315         addr = simple_strtoul(argv[1], NULL, 16);
 316         length = simple_strtoul(argv[2], NULL, 16);
 317         ivt_offset = simple_strtoul(argv[3], NULL, 16);
 318
 319         rcode = imx_hab_authenticate_image(addr, length, ivt_offset);
 320         if (rcode == 0)
 321                 rcode = CMD_RET_SUCCESS;
 322         else
 323                 rcode = CMD_RET_FAILURE;
 324
 325         return rcode;
 326 }
 327
 328 static int do_hab_failsafe(cmd_tbl_t *cmdtp, int flag, int argc,
 329                            char * const argv[])
 330 {
 331         hab_rvt_failsafe_t *hab_rvt_failsafe;
 332
 333         if (argc != 1) {
 334                 cmd_usage(cmdtp);
 335                 return 1;
 336         }
 337
 338         hab_rvt_failsafe = (hab_rvt_failsafe_t *)HAB_RVT_FAILSAFE;
 339         hab_rvt_failsafe();
 340
 341         return 0;
 342 }
 343
 344 static int do_authenticate_image_or_failover(cmd_tbl_t *cmdtp, int flag,
 345                                              int argc, char * const argv[])
 346 {
 347         int ret = CMD_RET_FAILURE;
 348
 349         if (argc != 4) {
 350                 ret = CMD_RET_USAGE;
 351                 goto error;
 352         }
 353
 354         if (!imx_hab_is_enabled()) {
 355                 printf("error: secure boot disabled\n");
 356                 goto error;
 357         }
 358
 359         if (do_authenticate_image(NULL, flag, argc, argv) != CMD_RET_SUCCESS) {
 360                 fprintf(stderr, "authentication fail -> %s %s %s %s\n",
 361                         argv[0], argv[1], argv[2], argv[3]);
 362                 do_hab_failsafe(0, 0, 1, NULL);
 363         };
 364         ret = CMD_RET_SUCCESS;
 365 error:
 366         return ret;
 367 }
 368
 369 U_BOOT_CMD(
 370                 hab_status, CONFIG_SYS_MAXARGS, 1, do_hab_status,
 371                 "display HAB status",
 372                 ""
 373           );
 374
 375 U_BOOT_CMD(
 376                 hab_auth_img, 4, 0, do_authenticate_image,
 377                 "authenticate image via HAB",
 378                 "addr length ivt_offset\n"
 379                 "addr - image hex address\n"
 380                 "length - image hex length\n"
 381                 "ivt_offset - hex offset of IVT in the image"
 382           );
 383
 384 U_BOOT_CMD(
 385                 hab_failsafe, CONFIG_SYS_MAXARGS, 1, do_hab_failsafe,
 386                 "run BootROM failsafe routine",
 387                 ""
 388           );
 389
 390 U_BOOT_CMD(
 391                 hab_auth_img_or_fail, 4, 0,
 392                 do_authenticate_image_or_failover,
 393                 "authenticate image via HAB on failure drop to USB BootROM mode",
 394                 "addr length ivt_offset\n"
 395                 "addr - image hex address\n"
 396                 "length - image hex length\n"
 397                 "ivt_offset - hex offset of IVT in the image"
 398           );
 399
 400 #endif /* !defined(CONFIG_SPL_BUILD) */
 401
 402 /* Get CSF Header length */
 403 static int get_hab_hdr_len(struct hab_hdr *hdr)
 404 {
 405         return (size_t)((hdr->len[0] << 8) + (hdr->len[1]));
 406 }
 407
 408 /* Check whether addr lies between start and
 409  * end and is within the length of the image
 410  */
 411 static int chk_bounds(u8 *addr, size_t bytes, u8 *start, u8 *end)
 412 {
 413         size_t csf_size = (size_t)((end + 1) - addr);
 414
 415         return (addr && (addr >= start) && (addr <= end) &&
 416                 (csf_size >= bytes));
 417 }
 418
 419 /* Get Length of each command in CSF */
 420 static int get_csf_cmd_hdr_len(u8 *csf_hdr)
 421 {
 422         if (*csf_hdr == HAB_CMD_HDR)
 423                 return sizeof(struct hab_hdr);
 424
 425         return get_hab_hdr_len((struct hab_hdr *)csf_hdr);
 426 }
 427
 428 /* Check if CSF is valid */
 429 static bool csf_is_valid(struct ivt *ivt, ulong start_addr, size_t bytes)
 430 {
 431         u8 *start = (u8 *)start_addr;
 432         u8 *csf_hdr;
 433         u8 *end;
 434
 435         size_t csf_hdr_len;
 436         size_t cmd_hdr_len;
 437         size_t offset = 0;
 438
 439         if (bytes != 0)
 440                 end = start + bytes - 1;
 441         else
 442                 end = start;
 443
 444         /* Verify if CSF pointer content is zero */
 445         if (!ivt->csf) {
 446                 puts("Error: CSF pointer is NULL\n");
 447                 return false;
 448         }
 449
 450         csf_hdr = (u8 *)ivt->csf;
 451
 452         /* Verify if CSF Header exist */
 453         if (*csf_hdr != HAB_CMD_HDR) {
 454                 puts("Error: CSF header command not found\n");
 455                 return false;
 456         }
 457
 458         csf_hdr_len = get_hab_hdr_len((struct hab_hdr *)csf_hdr);
 459
 460         /* Check if the CSF lies within the image bounds */
 461         if (!chk_bounds(csf_hdr, csf_hdr_len, start, end)) {
 462                 puts("Error: CSF lies outside the image bounds\n");
 463                 return false;
 464         }
 465
 466         do {
 467                 struct hab_hdr *cmd;
 468
 469                 cmd = (struct hab_hdr *)&csf_hdr[offset];
 470
 471                 switch (cmd->tag) {
 472                 case (HAB_CMD_WRT_DAT):
 473                         puts("Error: Deprecated write command found\n");
 474                         return false;
 475                 case (HAB_CMD_CHK_DAT):
 476                         puts("Error: Deprecated check command found\n");
 477                         return false;
 478                 case (HAB_CMD_SET):
 479                         if (cmd->par == HAB_PAR_MID) {
 480                                 puts("Error: Deprecated Set MID command found\n");
 481                                 return false;
 482                         }
 483                 default:
 484                         break;
 485                 }
 486
 487                 cmd_hdr_len = get_csf_cmd_hdr_len(&csf_hdr[offset]);
 488                 if (!cmd_hdr_len) {
 489                         puts("Error: Invalid command length\n");
 490                         return false;
 491                 }
 492                 offset += cmd_hdr_len;
 493
 494         } while (offset < csf_hdr_len);
 495
 496         return true;
 497 }
 498
 499 bool imx_hab_is_enabled(void)
 500 {
 501         struct imx_sec_config_fuse_t *fuse =
 502                 (struct imx_sec_config_fuse_t *)&imx_sec_config_fuse;
 503         uint32_t reg;
 504         int ret;
 505
 506         ret = fuse_read(fuse->bank, fuse->word, &reg);
 507         if (ret) {
 508                 puts("\nSecure boot fuse read error\n");
 509                 return ret;
 510         }
 511
 512         return (reg & IS_HAB_ENABLED_BIT) == IS_HAB_ENABLED_BIT;
 513 }
 514
 515 int imx_hab_authenticate_image(uint32_t ddr_start, uint32_t image_size,
 516                                uint32_t ivt_offset)
 517 {
 518         uint32_t load_addr = 0;
 519         size_t bytes;
 520         uint32_t ivt_addr = 0;
 521         int result = 1;
 522         ulong start;
 523         hab_rvt_authenticate_image_t *hab_rvt_authenticate_image;
 524         hab_rvt_entry_t *hab_rvt_entry;
 525         hab_rvt_exit_t *hab_rvt_exit;
 526         hab_rvt_check_target_t *hab_rvt_check_target;
 527         struct ivt *ivt;
 528         struct ivt_header *ivt_hdr;
 529         enum hab_status status;
 530
 531         hab_rvt_authenticate_image =
 532                 (hab_rvt_authenticate_image_t *)HAB_RVT_AUTHENTICATE_IMAGE;
 533         hab_rvt_entry = (hab_rvt_entry_t *)HAB_RVT_ENTRY;
 534         hab_rvt_exit = (hab_rvt_exit_t *)HAB_RVT_EXIT;
 535         hab_rvt_check_target = (hab_rvt_check_target_t *)HAB_RVT_CHECK_TARGET;
 536
 537         if (!imx_hab_is_enabled()) {
 538                 puts("hab fuse not enabled\n");
 539                 return 0;
 540         }
 541
 542         printf("\nAuthenticate image from DDR location 0x%x...\n",
 543                ddr_start);
 544
 545         hab_caam_clock_enable(1);
 546
 547         /* Calculate IVT address header */
 548         ivt_addr = ddr_start + ivt_offset;
 549         ivt = (struct ivt *)ivt_addr;
 550         ivt_hdr = &ivt->hdr;
 551
 552         /* Verify IVT header bugging out on error */
 553         if (verify_ivt_header(ivt_hdr))
 554                 goto hab_authentication_exit;
 555
 556         /* Verify IVT body */
 557         if (ivt->self != ivt_addr) {
 558                 printf("ivt->self 0x%08x pointer is 0x%08x\n",
 559                        ivt->self, ivt_addr);
 560                 goto hab_authentication_exit;
 561         }
 562
 563         /* Verify if IVT DCD pointer is NULL */
 564         if (ivt->dcd) {
 565                 puts("Error: DCD pointer must be NULL\n");
 566                 goto hab_authentication_exit;
 567         }
 568
 569         start = ddr_start;
 570         bytes = image_size;
 571
 572         /* Verify CSF */
 573         if (!csf_is_valid(ivt, start, bytes))
 574                 goto hab_authentication_exit;
 575
 576         if (hab_rvt_entry() != HAB_SUCCESS) {
 577                 puts("hab entry function fail\n");
 578                 goto hab_exit_failure_print_status;
 579         }
 580
 581         status = hab_rvt_check_target(HAB_TGT_MEMORY, (void *)ddr_start, bytes);
 582         if (status != HAB_SUCCESS) {
 583                 printf("HAB check target 0x%08x-0x%08x fail\n",
 584                        ddr_start, ddr_start + bytes);
 585                 goto hab_exit_failure_print_status;
 586         }
 587 #ifdef DEBUG
 588         printf("\nivt_offset = 0x%x, ivt addr = 0x%x\n", ivt_offset, ivt_addr);
 589         printf("ivt entry = 0x%08x, dcd = 0x%08x, csf = 0x%08x\n", ivt->entry,
 590                ivt->dcd, ivt->csf);
 591         puts("Dumping IVT\n");
 592         print_buffer(ivt_addr, (void *)(ivt_addr), 4, 0x8, 0);
 593
 594         puts("Dumping CSF Header\n");
 595         print_buffer(ivt->csf, (void *)(ivt->csf), 4, 0x10, 0);
 596
 597 #if  !defined(CONFIG_SPL_BUILD)
 598         get_hab_status();
 599 #endif
 600
 601         puts("\nCalling authenticate_image in ROM\n");
 602         printf("\tivt_offset = 0x%x\n", ivt_offset);
 603         printf("\tstart = 0x%08lx\n", start);
 604         printf("\tbytes = 0x%x\n", bytes);
 605 #endif
 606         /*
 607          * If the MMU is enabled, we have to notify the ROM
 608          * code, or it won't flush the caches when needed.
 609          * This is done, by setting the "pu_irom_mmu_enabled"
 610          * word to 1. You can find its address by looking in
 611          * the ROM map. This is critical for
 612          * authenticate_image(). If MMU is enabled, without
 613          * setting this bit, authentication will fail and may
 614          * crash.
 615          */
 616         /* Check MMU enabled */
 617         if (is_soc_type(MXC_SOC_MX6) && get_cr() & CR_M) {
 618                 if (is_mx6dq()) {
 619                         /*
 620                          * This won't work on Rev 1.0.0 of
 621                          * i.MX6Q/D, since their ROM doesn't
 622                          * do cache flushes. don't think any
 623                          * exist, so we ignore them.
 624                          */
 625                         if (!is_mx6dqp())
 626                                 writel(1, MX6DQ_PU_IROM_MMU_EN_VAR);
 627                 } else if (is_mx6sdl()) {
 628                         writel(1, MX6DLS_PU_IROM_MMU_EN_VAR);
 629                 } else if (is_mx6sl()) {
 630                         writel(1, MX6SL_PU_IROM_MMU_EN_VAR);
 631                 }
 632         }
 633
 634         load_addr = (uint32_t)hab_rvt_authenticate_image(
 635                         HAB_CID_UBOOT,
 636                         ivt_offset, (void **)&start,
 637                         (size_t *)&bytes, NULL);
 638         if (hab_rvt_exit() != HAB_SUCCESS) {
 639                 puts("hab exit function fail\n");
 640                 load_addr = 0;
 641         }
 642
 643 hab_exit_failure_print_status:
 644 #if !defined(CONFIG_SPL_BUILD)
 645         get_hab_status();
 646 #endif
 647
 648 hab_authentication_exit:
 649
 650         if (load_addr != 0)
 651                 result = 0;
 652
 653         return result;
 654 }