arch/arm/cpu/armv8/sec_firmware.c

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