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