arch/arm/cpu/armv8/sec_firmware.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2016 NXP Semiconductor, Inc.
   4  */
   5
   6 #include <common.h>
   7 #include <cpu_func.h>
   8 #include <errno.h>
   9 #include <fdt_support.h>
  10 #include <image.h>
  11 #include <log.h>
  12 #include <asm/cache.h>
  13 #include <linux/kernel.h>
  14 #include <asm/io.h>
  15 #include <asm/system.h>
  16 #include <asm/types.h>
  17 #include <asm/macro.h>
  18 #include <asm/armv8/sec_firmware.h>
  19
  20 DECLARE_GLOBAL_DATA_PTR;
  21 extern void c_runtime_cpu_setup(void);
  22
  23 #define SEC_FIRMWARE_LOADED     0x1
  24 #define SEC_FIRMWARE_RUNNING    0x2
  25 #define SEC_FIRMWARE_ADDR_MASK  (~0x3)
  26 /*
  27  * Secure firmware load addr
  28  * Flags used: 0x1 secure firmware has been loaded to secure memory
  29  *             0x2 secure firmware is running
  30  */
  31 phys_addr_t sec_firmware_addr;
  32
  33 #ifndef SEC_FIRMWARE_FIT_IMAGE
  34 #define SEC_FIRMWARE_FIT_IMAGE          "firmware"
  35 #endif
  36 #ifndef SEC_FIRMWARE_FIT_CNF_NAME
  37 #define SEC_FIRMWARE_FIT_CNF_NAME       "config-1"
  38 #endif
  39 #ifndef SEC_FIRMWARE_TARGET_EL
  40 #define SEC_FIRMWARE_TARGET_EL          2
  41 #endif
  42
  43 static int sec_firmware_get_data(const void *sec_firmware_img,
  44                                 const void **data, size_t *size)
  45 {
  46         int conf_node_off, fw_node_off;
  47         char *conf_node_name = NULL;
  48         char *desc;
  49         int ret;
  50
  51         conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
  52
  53         conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
  54         if (conf_node_off < 0) {
  55                 printf("SEC Firmware: %s: no such config\n", conf_node_name);
  56                 return -ENOENT;
  57         }
  58
  59         fw_node_off = fit_conf_get_prop_node(sec_firmware_img, conf_node_off,
  60                         SEC_FIRMWARE_FIT_IMAGE);
  61         if (fw_node_off < 0) {
  62                 printf("SEC Firmware: No '%s' in config\n",
  63                        SEC_FIRMWARE_FIT_IMAGE);
  64                 return -ENOLINK;
  65         }
  66
  67         /* Verify secure firmware image */
  68         if (!(fit_image_verify(sec_firmware_img, fw_node_off))) {
  69                 printf("SEC Firmware: Bad firmware image (bad CRC)\n");
  70                 return -EINVAL;
  71         }
  72
  73         if (fit_image_get_data(sec_firmware_img, fw_node_off, data, size)) {
  74                 printf("SEC Firmware: Can't get %s subimage data/size",
  75                        SEC_FIRMWARE_FIT_IMAGE);
  76                 return -ENOENT;
  77         }
  78
  79         ret = fit_get_desc(sec_firmware_img, fw_node_off, &desc);
  80         if (ret)
  81                 printf("SEC Firmware: Can't get description\n");
  82         else
  83                 printf("%s\n", desc);
  84
  85         return ret;
  86 }
  87
  88 /*
  89  * SEC Firmware FIT image parser checks if the image is in FIT
  90  * format, verifies integrity of the image and calculates raw
  91  * image address and size values.
  92  *
  93  * Returns 0 on success and a negative errno on error task fail.
  94  */
  95 static int sec_firmware_parse_image(const void *sec_firmware_img,
  96                                         const void **raw_image_addr,
  97                                         size_t *raw_image_size)
  98 {
  99         int ret;
 100
 101         ret = sec_firmware_get_data(sec_firmware_img, raw_image_addr,
 102                                         raw_image_size);
 103         if (ret)
 104                 return ret;
 105
 106         debug("SEC Firmware: raw_image_addr = 0x%p, raw_image_size = 0x%lx\n",
 107               *raw_image_addr, *raw_image_size);
 108
 109         return 0;
 110 }
 111
 112 /*
 113  * SEC Firmware FIT image parser to check if any loadable is
 114  * present. If present, verify integrity of the loadable and
 115  * copy loadable to address provided in (loadable_h, loadable_l).
 116  *
 117  * Returns 0 on success and a negative errno on error task fail.
 118  */
 119 static int sec_firmware_check_copy_loadable(const void *sec_firmware_img,
 120                                             u32 *loadable_l, u32 *loadable_h)
 121 {
 122         phys_addr_t sec_firmware_loadable_addr = 0;
 123         int conf_node_off, ld_node_off, images;
 124         char *conf_node_name = NULL;
 125         const void *data;
 126         size_t size;
 127         ulong load;
 128         const char *name, *str, *type;
 129         int len;
 130
 131         conf_node_name = SEC_FIRMWARE_FIT_CNF_NAME;
 132
 133         conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
 134         if (conf_node_off < 0) {
 135                 printf("SEC Firmware: %s: no such config\n", conf_node_name);
 136                 return -ENOENT;
 137         }
 138
 139         /* find the node holding the images information */
 140         images = fdt_path_offset(sec_firmware_img, FIT_IMAGES_PATH);
 141         if (images < 0) {
 142                 printf("%s: Cannot find /images node: %d\n", __func__, images);
 143                 return -1;
 144         }
 145
 146         type = FIT_LOADABLE_PROP;
 147
 148         name = fdt_getprop(sec_firmware_img, conf_node_off, type, &len);
 149         if (!name) {
 150                 /* Loadables not present */
 151                 return 0;
 152         }
 153
 154         printf("SEC Firmware: '%s' present in config\n", type);
 155
 156         for (str = name; str && ((str - name) < len);
 157              str = strchr(str, '\0') + 1) {
 158                 printf("%s: '%s'\n", type, str);
 159                 ld_node_off = fdt_subnode_offset(sec_firmware_img, images, str);
 160                 if (ld_node_off < 0) {
 161                         printf("cannot find image node '%s': %d\n", str,
 162                                ld_node_off);
 163                         return -EINVAL;
 164                 }
 165
 166                 /* Verify secure firmware image */
 167                 if (!(fit_image_verify(sec_firmware_img, ld_node_off))) {
 168                         printf("SEC Loadable: Bad loadable image (bad CRC)\n");
 169                         return -EINVAL;
 170                 }
 171
 172                 if (fit_image_get_data(sec_firmware_img, ld_node_off,
 173                                        &data, &size)) {
 174                         printf("SEC Loadable: Can't get subimage data/size");
 175                         return -ENOENT;
 176                 }
 177
 178                 /* Get load address, treated as load offset to secure memory */
 179                 if (fit_image_get_load(sec_firmware_img, ld_node_off, &load)) {
 180                         printf("SEC Loadable: Can't get subimage load");
 181                         return -ENOENT;
 182                 }
 183
 184                 /* Compute load address for loadable in secure memory */
 185                 sec_firmware_loadable_addr = (sec_firmware_addr -
 186                                                 gd->arch.tlb_size) + load;
 187
 188                 /* Copy loadable to secure memory and flush dcache */
 189                 debug("%s copied to address 0x%p\n",
 190                       FIT_LOADABLE_PROP, (void *)sec_firmware_loadable_addr);
 191                 memcpy((void *)sec_firmware_loadable_addr, data, size);
 192                 flush_dcache_range(sec_firmware_loadable_addr,
 193                                    sec_firmware_loadable_addr + size);
 194
 195                 /* Populate loadable address only for Trusted OS */
 196                 if (!strcmp(str, "trustedOS@1")) {
 197                         /*
 198                          * Populate address ptrs for loadable image with
 199                          * loadbale addr
 200                          */
 201                         out_le32(loadable_l, (sec_firmware_loadable_addr &
 202                                               WORD_MASK));
 203                         out_le32(loadable_h, (sec_firmware_loadable_addr >>
 204                                               WORD_SHIFT));
 205                 }
 206         }
 207
 208         return 0;
 209 }
 210
 211 static int sec_firmware_copy_image(const char *title,
 212                          u64 image_addr, u32 image_size, u64 sec_firmware)
 213 {
 214         debug("%s copied to address 0x%p\n", title, (void *)sec_firmware);
 215         memcpy((void *)sec_firmware, (void *)image_addr, image_size);
 216         flush_dcache_range(sec_firmware, sec_firmware + image_size);
 217
 218         return 0;
 219 }
 220
 221 /*
 222  * This function will parse the SEC Firmware image, and then load it
 223  * to secure memory. Also load any loadable if present along with SEC
 224  * Firmware image.
 225  */
 226 static int sec_firmware_load_image(const void *sec_firmware_img,
 227                                    u32 *loadable_l, u32 *loadable_h)
 228 {
 229         const void *raw_image_addr;
 230         size_t raw_image_size = 0;
 231         int ret;
 232
 233         /*
 234          * The Excetpion Level must be EL3 to load and initialize
 235          * the SEC Firmware.
 236          */
 237         if (current_el() != 3) {
 238                 ret = -EACCES;
 239                 goto out;
 240         }
 241
 242 #ifdef CONFIG_SYS_MEM_RESERVE_SECURE
 243         /*
 244          * The SEC Firmware must be stored in secure memory.
 245          * Append SEC Firmware to secure mmu table.
 246          */
 247         if (!(gd->arch.secure_ram & MEM_RESERVE_SECURE_MAINTAINED)) {
 248                 ret = -ENXIO;
 249                 goto out;
 250         }
 251
 252         sec_firmware_addr = (gd->arch.secure_ram & MEM_RESERVE_SECURE_ADDR_MASK) +
 253                         gd->arch.tlb_size;
 254 #else
 255 #error "The CONFIG_SYS_MEM_RESERVE_SECURE must be defined when enabled SEC Firmware support"
 256 #endif
 257
 258         /* Align SEC Firmware base address to 4K */
 259         sec_firmware_addr = (sec_firmware_addr + 0xfff) & ~0xfff;
 260         debug("SEC Firmware: Load address: 0x%llx\n",
 261               sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
 262
 263         ret = sec_firmware_parse_image(sec_firmware_img, &raw_image_addr,
 264                         &raw_image_size);
 265         if (ret)
 266                 goto out;
 267
 268         /* TODO:
 269          * Check if the end addr of SEC Firmware has been extend the secure
 270          * memory.
 271          */
 272
 273         /* Copy the secure firmware to secure memory */
 274         ret = sec_firmware_copy_image("SEC Firmware", (u64)raw_image_addr,
 275                         raw_image_size, sec_firmware_addr &
 276                         SEC_FIRMWARE_ADDR_MASK);
 277         if (ret)
 278                 goto out;
 279
 280         /*
 281          * Check if any loadable are present along with firmware image, if
 282          * present load them.
 283          */
 284         ret = sec_firmware_check_copy_loadable(sec_firmware_img, loadable_l,
 285                                                loadable_h);
 286         if (ret)
 287                 goto out;
 288
 289         sec_firmware_addr |= SEC_FIRMWARE_LOADED;
 290         debug("SEC Firmware: Entry point: 0x%llx\n",
 291               sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
 292
 293         return 0;
 294
 295 out:
 296         printf("SEC Firmware: error (%d)\n", ret);
 297         sec_firmware_addr = 0;
 298
 299         return ret;
 300 }
 301
 302 static int sec_firmware_entry(u32 *eret_hold_l, u32 *eret_hold_h)
 303 {
 304         const void *entry = (void *)(sec_firmware_addr &
 305                                 SEC_FIRMWARE_ADDR_MASK);
 306
 307         return _sec_firmware_entry(entry, eret_hold_l, eret_hold_h);
 308 }
 309
 310 /* Check the secure firmware FIT image */
 311 __weak bool sec_firmware_is_valid(const void *sec_firmware_img)
 312 {
 313         if (fdt_check_header(sec_firmware_img)) {
 314                 printf("SEC Firmware: Bad firmware image (not a FIT image)\n");
 315                 return false;
 316         }
 317
 318         if (!fit_check_format(sec_firmware_img)) {
 319                 printf("SEC Firmware: Bad firmware image (bad FIT header)\n");
 320                 return false;
 321         }
 322
 323         return true;
 324 }
 325
 326 #ifdef CONFIG_SEC_FIRMWARE_ARMV8_PSCI
 327 /*
 328  * The PSCI_VERSION function is added from PSCI v0.2. When the PSCI
 329  * v0.1 received this function, the NOT_SUPPORTED (0xffff_ffff) error
 330  * number will be returned according to SMC Calling Conventions. But
 331  * when getting the NOT_SUPPORTED error number, we cannot ensure if
 332  * the PSCI version is v0.1 or other error occurred. So, PSCI v0.1
 333  * won't be supported by this framework.
 334  * And if the secure firmware isn't running, return NOT_SUPPORTED.
 335  *
 336  * The return value on success is PSCI version in format
 337  * major[31:16]:minor[15:0].
 338  */
 339 unsigned int sec_firmware_support_psci_version(void)
 340 {
 341         if (current_el() == SEC_FIRMWARE_TARGET_EL)
 342                 return _sec_firmware_support_psci_version();
 343
 344         return PSCI_INVALID_VER;
 345 }
 346 #endif
 347
 348 /*
 349  * Check with sec_firmware if it supports random number generation
 350  * via HW RNG
 351  *
 352  * The return value will be true if it is supported
 353  */
 354 bool sec_firmware_support_hwrng(void)
 355 {
 356 #ifdef CONFIG_TFABOOT
 357         /* return true as TFA has one job ring reserved */
 358         return true;
 359 #endif
 360         if (sec_firmware_addr & SEC_FIRMWARE_RUNNING) {
 361                 return true;
 362         }
 363
 364         return false;
 365 }
 366
 367 /*
 368  * sec_firmware_get_random - Get a random number from SEC Firmware
 369  * @rand:               random number buffer to be filled
 370  * @bytes:              Number of bytes of random number to be supported
 371  * @eret:               -1 in case of error, 0 for success
 372  */
 373 int sec_firmware_get_random(uint8_t *rand, int bytes)
 374 {
 375         unsigned long long num;
 376         struct pt_regs regs;
 377         int param1;
 378
 379         if (!bytes || bytes > 8) {
 380                 printf("Max Random bytes genration supported is 8\n");
 381                 return -1;
 382         }
 383 #define SIP_RNG_64 0xC200FF11
 384         regs.regs[0] = SIP_RNG_64;
 385
 386         if (bytes <= 4)
 387                 param1 = 0;
 388         else
 389                 param1 = 1;
 390         regs.regs[1] = param1;
 391
 392         smc_call(&regs);
 393
 394         if (regs.regs[0])
 395                 return -1;
 396
 397         num = regs.regs[1];
 398         memcpy(rand, &num, bytes);
 399
 400         return 0;
 401 }
 402
 403 /*
 404  * sec_firmware_init - Initialize the SEC Firmware
 405  * @sec_firmware_img:   the SEC Firmware image address
 406  * @eret_hold_l:        the address to hold exception return address low
 407  * @eret_hold_h:        the address to hold exception return address high
 408  * @loadable_l:         the address to hold loadable address low
 409  * @loadable_h:         the address to hold loadable address high
 410  */
 411 int sec_firmware_init(const void *sec_firmware_img,
 412                         u32 *eret_hold_l,
 413                         u32 *eret_hold_h,
 414                         u32 *loadable_l,
 415                         u32 *loadable_h)
 416 {
 417         int ret;
 418
 419         if (!sec_firmware_is_valid(sec_firmware_img))
 420                 return -EINVAL;
 421
 422         ret = sec_firmware_load_image(sec_firmware_img, loadable_l,
 423                                       loadable_h);
 424         if (ret) {
 425                 printf("SEC Firmware: Failed to load image\n");
 426                 return ret;
 427         } else if (sec_firmware_addr & SEC_FIRMWARE_LOADED) {
 428                 ret = sec_firmware_entry(eret_hold_l, eret_hold_h);
 429                 if (ret) {
 430                         printf("SEC Firmware: Failed to initialize\n");
 431                         return ret;
 432                 }
 433         }
 434
 435         debug("SEC Firmware: Return from SEC Firmware: current_el = %d\n",
 436               current_el());
 437
 438         /*
 439          * The PE will be turned into target EL when returned from
 440          * SEC Firmware.
 441          */
 442         if (current_el() != SEC_FIRMWARE_TARGET_EL)
 443                 return -EACCES;
 444
 445         sec_firmware_addr |= SEC_FIRMWARE_RUNNING;
 446
 447         /* Set exception table and enable caches if it isn't EL3 */
 448         if (current_el() != 3) {
 449                 c_runtime_cpu_setup();
 450                 enable_caches();
 451         }
 452
 453         return 0;
 454 }
 455
 456 /*
 457  * fdt_fix_kaslr - Add kalsr-seed node in Device tree
 458  * @fdt:                Device tree
 459  * @eret:               0 in case of error, 1 for success
 460  */
 461 int fdt_fixup_kaslr(void *fdt)
 462 {
 463         int nodeoffset;
 464         int err, ret = 0;
 465         u8 rand[8];
 466
 467 #if defined(CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT)
 468         /* Check if random seed generation is  supported */
 469         if (sec_firmware_support_hwrng() == false) {
 470                 printf("WARNING: SEC firmware not running, no kaslr-seed\n");
 471                 return 0;
 472         }
 473
 474         ret = sec_firmware_get_random(rand, 8);
 475         if (ret < 0) {
 476                 printf("WARNING: No random number to set kaslr-seed\n");
 477                 return 0;
 478         }
 479
 480         err = fdt_check_header(fdt);
 481         if (err < 0) {
 482                 printf("fdt_chosen: %s\n", fdt_strerror(err));
 483                 return 0;
 484         }
 485
 486         /* find or create "/chosen" node. */
 487         nodeoffset = fdt_find_or_add_subnode(fdt, 0, "chosen");
 488         if (nodeoffset < 0)
 489                 return 0;
 490
 491         err = fdt_setprop(fdt, nodeoffset, "kaslr-seed", rand,
 492                                   sizeof(rand));
 493         if (err < 0) {
 494                 printf("WARNING: can't set kaslr-seed %s.\n",
 495                        fdt_strerror(err));
 496                 return 0;
 497         }
 498         ret = 1;
 499 #endif
 500
 501         return ret;
 502 }