src/lib/fit.c

   1 /* Taken from depthcharge: src/boot/fit.c */
   2 /* SPDX-License-Identifier: GPL-2.0-or-later */
   3
   4 #include <assert.h>
   5 #include <console/console.h>
   6 #include <ctype.h>
   7 #include <endian.h>
   8 #include <bootmem.h>
   9 #include <string.h>
  10 #include <program_loading.h>
  11 #include <memrange.h>
  12 #include <fit.h>
  13 #include <boardid.h>
  14 #include <commonlib/stdlib.h>
  15 #include <types.h>
  16
  17 static struct list_node image_nodes;
  18 static struct list_node config_nodes;
  19 static struct list_node compat_strings;
  20
  21 struct compat_string_entry {
  22         const char *compat_string;
  23         struct list_node list_node;
  24 };
  25
  26 /* Convert string to lowercase and replace '_' and spaces with '-'. */
  27 static char *clean_compat_string(char *str)
  28 {
  29         for (size_t i = 0; i < strlen(str); i++) {
  30                 str[i] = tolower(str[i]);
  31                 if (str[i] == '_' || str[i] == ' ')
  32                         str[i] = '-';
  33         }
  34
  35         return str;
  36 }
  37
  38 static void fit_add_default_compat_strings(void)
  39 {
  40         char compat_string[80] = {};
  41
  42         if ((board_id() != UNDEFINED_STRAPPING_ID) &&
  43             (sku_id() != UNDEFINED_STRAPPING_ID)) {
  44                 snprintf(compat_string, sizeof(compat_string),
  45                          "%s,%s-rev%u-sku%u", CONFIG_MAINBOARD_VENDOR,
  46                          CONFIG_MAINBOARD_PART_NUMBER, board_id(), sku_id());
  47
  48                 fit_add_compat_string(compat_string);
  49         }
  50
  51         if (board_id() != UNDEFINED_STRAPPING_ID) {
  52                 snprintf(compat_string, sizeof(compat_string), "%s,%s-rev%u",
  53                          CONFIG_MAINBOARD_VENDOR, CONFIG_MAINBOARD_PART_NUMBER,
  54                          board_id());
  55
  56                 fit_add_compat_string(compat_string);
  57         }
  58
  59         if (sku_id() != UNDEFINED_STRAPPING_ID) {
  60                 snprintf(compat_string, sizeof(compat_string), "%s,%s-sku%u",
  61                          CONFIG_MAINBOARD_VENDOR, CONFIG_MAINBOARD_PART_NUMBER,
  62                          sku_id());
  63
  64                 fit_add_compat_string(compat_string);
  65         }
  66
  67         snprintf(compat_string, sizeof(compat_string), "%s,%s",
  68                  CONFIG_MAINBOARD_VENDOR, CONFIG_MAINBOARD_PART_NUMBER);
  69
  70         fit_add_compat_string(compat_string);
  71 }
  72
  73 static struct fit_image_node *find_image(const char *name)
  74 {
  75         struct fit_image_node *image;
  76         list_for_each(image, image_nodes, list_node) {
  77                 if (!strcmp(image->name, name))
  78                         return image;
  79         }
  80         printk(BIOS_ERR, "Cannot find image node %s!\n", name);
  81         return NULL;
  82 }
  83
  84 static struct fit_image_node *find_image_with_overlays(const char *name,
  85         int bytes, struct list_node *prev)
  86 {
  87         struct fit_image_node *base = find_image(name);
  88         if (!base)
  89                 return NULL;
  90
  91         int len = strnlen(name, bytes) + 1;
  92         bytes -= len;
  93         name += len;
  94         while (bytes > 0) {
  95                 struct fit_overlay_chain *next = xzalloc(sizeof(*next));
  96                 next->overlay = find_image(name);
  97                 if (!next->overlay)
  98                         return NULL;
  99                 list_insert_after(&next->list_node, prev);
 100                 prev = &next->list_node;
 101                 len = strnlen(name, bytes) + 1;
 102                 bytes -= len;
 103                 name += len;
 104         }
 105
 106         return base;
 107 }
 108
 109 static void image_node(struct device_tree_node *node)
 110 {
 111         struct fit_image_node *image = xzalloc(sizeof(*image));
 112
 113         image->compression = CBFS_COMPRESS_NONE;
 114         image->name = node->name;
 115
 116         struct device_tree_property *prop;
 117         list_for_each(prop, node->properties, list_node) {
 118                 if (!strcmp("data", prop->prop.name)) {
 119                         image->data = prop->prop.data;
 120                         image->size = prop->prop.size;
 121                 } else if (!strcmp("compression", prop->prop.name)) {
 122                         if (!strcmp("none", prop->prop.data))
 123                                 image->compression = CBFS_COMPRESS_NONE;
 124                         else if (!strcmp("lzma", prop->prop.data))
 125                                 image->compression = CBFS_COMPRESS_LZMA;
 126                         else if (!strcmp("lz4", prop->prop.data))
 127                                 image->compression = CBFS_COMPRESS_LZ4;
 128                         else
 129                                 image->compression = -1;
 130                 }
 131         }
 132
 133         list_insert_after(&image->list_node, &image_nodes);
 134 }
 135
 136 static void config_node(struct device_tree_node *node)
 137 {
 138         struct fit_config_node *config = xzalloc(sizeof(*config));
 139         config->name = node->name;
 140
 141         struct device_tree_property *prop;
 142         list_for_each(prop, node->properties, list_node) {
 143                 if (!strcmp("kernel", prop->prop.name))
 144                         config->kernel = find_image(prop->prop.data);
 145                 else if (!strcmp("fdt", prop->prop.name))
 146                         config->fdt = find_image_with_overlays(prop->prop.data,
 147                                 prop->prop.size, &config->overlays);
 148                 else if (!strcmp("ramdisk", prop->prop.name))
 149                         config->ramdisk = find_image(prop->prop.data);
 150                 else if (!strcmp("compatible", prop->prop.name))
 151                         config->compat = prop->prop;
 152         }
 153
 154         list_insert_after(&config->list_node, &config_nodes);
 155 }
 156
 157 static void fit_unpack(struct device_tree *tree, const char **default_config)
 158 {
 159         struct device_tree_node *child;
 160         struct device_tree_node *images = dt_find_node_by_path(tree, "/images",
 161                                                                NULL, NULL, 0);
 162         if (images)
 163                 list_for_each(child, images->children, list_node)
 164                         image_node(child);
 165
 166         struct device_tree_node *configs = dt_find_node_by_path(tree,
 167                 "/configurations", NULL, NULL, 0);
 168         if (configs) {
 169                 *default_config = dt_find_string_prop(configs, "default");
 170                 list_for_each(child, configs->children, list_node)
 171                         config_node(child);
 172         }
 173 }
 174
 175 static int fdt_find_compat(const void *blob, uint32_t start_offset,
 176                            struct fdt_property *prop)
 177 {
 178         int offset = start_offset;
 179         int size;
 180
 181         size = fdt_node_name(blob, offset, NULL);
 182         if (!size)
 183                 return -1;
 184         offset += size;
 185
 186         while ((size = fdt_next_property(blob, offset, prop))) {
 187                 if (!strcmp("compatible", prop->name))
 188                         return 0;
 189
 190                 offset += size;
 191         }
 192
 193         prop->name = NULL;
 194         return -1;
 195 }
 196
 197 static int fit_check_compat(struct fdt_property *compat_prop,
 198                             const char *compat_name)
 199 {
 200         int bytes = compat_prop->size;
 201         const char *compat_str = compat_prop->data;
 202
 203         for (int pos = 0; bytes && compat_str[0]; pos++) {
 204                 if (!strncmp(compat_str, compat_name, bytes))
 205                         return pos;
 206                 int len = strlen(compat_str) + 1;
 207                 compat_str += len;
 208                 bytes -= len;
 209         }
 210         return -1;
 211 }
 212
 213 void fit_update_chosen(struct device_tree *tree, const char *cmd_line)
 214 {
 215         const char *path[] = { "chosen", NULL };
 216         struct device_tree_node *node;
 217         node = dt_find_node(tree->root, path, NULL, NULL, 1);
 218
 219         dt_add_string_prop(node, "bootargs", cmd_line);
 220 }
 221
 222 void fit_add_ramdisk(struct device_tree *tree, void *ramdisk_addr,
 223                      size_t ramdisk_size)
 224 {
 225         const char *path[] = { "chosen", NULL };
 226         struct device_tree_node *node;
 227         node = dt_find_node(tree->root, path, NULL, NULL, 1);
 228
 229         u64 start = (uintptr_t)ramdisk_addr;
 230         u64 end = start + ramdisk_size;
 231
 232         dt_add_u64_prop(node, "linux,initrd-start", start);
 233         dt_add_u64_prop(node, "linux,initrd-end", end);
 234 }
 235
 236 static void update_reserve_map(uint64_t start, uint64_t end,
 237                                struct device_tree *tree)
 238 {
 239         struct device_tree_reserve_map_entry *entry = xzalloc(sizeof(*entry));
 240
 241         entry->start = start;
 242         entry->size = end - start;
 243
 244         list_insert_after(&entry->list_node, &tree->reserve_map);
 245 }
 246
 247 struct entry_params {
 248         unsigned int addr_cells;
 249         unsigned int size_cells;
 250         void *data;
 251 };
 252
 253 static uint64_t max_range(unsigned int size_cells)
 254 {
 255         /*
 256          * Split up ranges who's sizes are too large to fit in #size-cells.
 257          * The largest value we can store isn't a power of two, so we'll round
 258          * down to make the math easier.
 259          */
 260         return 0x1ULL << (size_cells * 32 - 1);
 261 }
 262
 263 static void update_mem_property(u64 start, u64 end, struct entry_params *params)
 264 {
 265         u8 *data = (u8 *)params->data;
 266         u64 full_size = end - start;
 267         while (full_size) {
 268                 const u64 max_size = max_range(params->size_cells);
 269                 const u64 size = MIN(max_size, full_size);
 270
 271                 dt_write_int(data, start, params->addr_cells * sizeof(u32));
 272                 data += params->addr_cells * sizeof(uint32_t);
 273                 start += size;
 274
 275                 dt_write_int(data, size, params->size_cells * sizeof(u32));
 276                 data += params->size_cells * sizeof(uint32_t);
 277                 full_size -= size;
 278         }
 279         params->data = data;
 280 }
 281
 282 struct mem_map {
 283         struct memranges mem;
 284         struct memranges reserved;
 285 };
 286
 287 static bool walk_memory_table(const struct range_entry *r, void *arg)
 288 {
 289         struct mem_map *arg_map = arg;
 290         struct memranges *ranges;
 291         enum bootmem_type tag;
 292
 293         ranges = range_entry_tag(r) == BM_MEM_RAM ? &arg_map->mem : &arg_map->reserved;
 294         tag = range_entry_tag(r) == BM_MEM_RAM ? BM_MEM_RAM : BM_MEM_RESERVED;
 295         memranges_insert(ranges, range_entry_base(r), range_entry_size(r), tag);
 296         return true;
 297 }
 298
 299 void fit_add_compat_string(const char *str)
 300 {
 301         struct compat_string_entry *compat_node;
 302
 303         compat_node = xzalloc(sizeof(*compat_node));
 304         compat_node->compat_string = strdup(str);
 305
 306         clean_compat_string((char *)compat_node->compat_string);
 307
 308         list_insert_after(&compat_node->list_node, &compat_strings);
 309 }
 310
 311 void fit_update_memory(struct device_tree *tree)
 312 {
 313         const struct range_entry *r;
 314         struct device_tree_node *node;
 315         u32 addr_cells = 1, size_cells = 1;
 316         struct mem_map map;
 317
 318         printk(BIOS_INFO, "FIT: Updating devicetree memory entries\n");
 319
 320         dt_read_cell_props(tree->root, &addr_cells, &size_cells);
 321
 322         /*
 323          * First remove all existing device_type="memory" nodes, then add ours.
 324          */
 325         list_for_each(node, tree->root->children, list_node) {
 326                 const char *devtype = dt_find_string_prop(node, "device_type");
 327                 if (devtype && !strcmp(devtype, "memory"))
 328                         list_remove(&node->list_node);
 329         }
 330
 331         node = xzalloc(sizeof(*node));
 332
 333         node->name = "memory";
 334         list_insert_after(&node->list_node, &tree->root->children);
 335         dt_add_string_prop(node, "device_type", (char *)"memory");
 336
 337         memranges_init_empty(&map.mem, NULL, 0);
 338         memranges_init_empty(&map.reserved, NULL, 0);
 339
 340         bootmem_walk_os_mem(walk_memory_table, &map);
 341
 342         /* CBMEM regions are both carved out and explicitly reserved. */
 343         memranges_each_entry(r, &map.reserved) {
 344                 update_reserve_map(range_entry_base(r), range_entry_end(r),
 345                                    tree);
 346         }
 347
 348         /*
 349          * Count the amount of 'reg' entries we need (account for size limits).
 350          */
 351         size_t count = 0;
 352         memranges_each_entry(r, &map.mem) {
 353                 uint64_t size = range_entry_size(r);
 354                 uint64_t max_size = max_range(size_cells);
 355                 count += DIV_ROUND_UP(size, max_size);
 356         }
 357
 358         /* Allocate the right amount of space and fill up the entries. */
 359         size_t length = count * (addr_cells + size_cells) * sizeof(u32);
 360
 361         void *data = xzalloc(length);
 362
 363         struct entry_params add_params = { addr_cells, size_cells, data };
 364         memranges_each_entry(r, &map.mem) {
 365                 update_mem_property(range_entry_base(r), range_entry_end(r),
 366                                     &add_params);
 367         }
 368         assert(add_params.data - data == length);
 369
 370         /* Assemble the final property and add it to the device tree. */
 371         dt_add_bin_prop(node, "reg", data, length);
 372
 373         memranges_teardown(&map.mem);
 374         memranges_teardown(&map.reserved);
 375 }
 376
 377 /*
 378  * Finds a compat string and updates the compat position and rank.
 379  * @param config The current config node to operate on
 380  * @return 0 if compat updated, -1 if this FDT cannot be used.
 381  */
 382 static int fit_update_compat(struct fit_config_node *config)
 383 {
 384         /* If there was no "compatible" property in config node, this is a
 385            legacy FIT image. Must extract compat prop from FDT itself. */
 386         if (!config->compat.name) {
 387                 void *fdt_blob = config->fdt->data;
 388                 const struct fdt_header *fdt_header = fdt_blob;
 389                 uint32_t fdt_offset = be32_to_cpu(fdt_header->structure_offset);
 390
 391                 if (config->fdt->compression != CBFS_COMPRESS_NONE) {
 392                         printk(BIOS_ERR, "config %s has a compressed FDT without "
 393                                "external compatible property, skipping.\n",
 394                                config->name);
 395                         return -1;
 396                 }
 397
 398                 /* FDT overlays are not supported in legacy FIT images. */
 399                 if (config->overlays.next) {
 400                         printk(BIOS_ERR, "config %s has overlay but no compat!\n",
 401                                config->name);
 402                         return -1;
 403                 }
 404
 405                 if (fdt_find_compat(fdt_blob, fdt_offset, &config->compat)) {
 406                         printk(BIOS_ERR, "Can't find compat string in FDT %s "
 407                                "for config %s, skipping.\n",
 408                                config->fdt->name, config->name);
 409                         return -1;
 410                 }
 411         }
 412
 413         config->compat_pos = -1;
 414         config->compat_rank = -1;
 415         size_t i = 0;
 416         struct compat_string_entry *compat_node;
 417         list_for_each(compat_node, compat_strings, list_node) {
 418                 int pos = fit_check_compat(&config->compat,
 419                                            compat_node->compat_string);
 420                 if (pos >= 0) {
 421                         config->compat_pos = pos;
 422                         config->compat_rank = i;
 423                         config->compat_string =
 424                                 compat_node->compat_string;
 425                 }
 426                 i++;
 427         }
 428
 429         return 0;
 430 }
 431
 432 struct fit_config_node *fit_load(void *fit)
 433 {
 434         struct fit_image_node *image;
 435         struct fit_config_node *config;
 436         struct compat_string_entry *compat_node;
 437         struct fit_overlay_chain *overlay_chain;
 438
 439         printk(BIOS_DEBUG, "FIT: Loading FIT from %p\n", fit);
 440
 441         struct device_tree *tree = fdt_unflatten(fit);
 442         if (!tree) {
 443                 printk(BIOS_ERR, "Failed to unflatten FIT image!\n");
 444                 return NULL;
 445         }
 446
 447         const char *default_config_name = NULL;
 448         struct fit_config_node *default_config = NULL;
 449         struct fit_config_node *compat_config = NULL;
 450
 451         fit_unpack(tree, &default_config_name);
 452
 453         /* List the images we found. */
 454         list_for_each(image, image_nodes, list_node)
 455                 printk(BIOS_DEBUG, "FIT: Image %s has %d bytes.\n", image->name,
 456                        image->size);
 457
 458         fit_add_default_compat_strings();
 459
 460         printk(BIOS_DEBUG, "FIT: Compat preference "
 461                "(lowest to highest priority) :");
 462
 463         list_for_each(compat_node, compat_strings, list_node) {
 464                 printk(BIOS_DEBUG, " %s", compat_node->compat_string);
 465         }
 466         printk(BIOS_DEBUG, "\n");
 467         /* Process and list the configs. */
 468         list_for_each(config, config_nodes, list_node) {
 469                 if (!config->kernel) {
 470                         printk(BIOS_ERR, "config %s has no kernel, skipping.\n",
 471                                config->name);
 472                         continue;
 473                 }
 474                 if (!config->fdt) {
 475                         printk(BIOS_ERR, "config %s has no FDT, skipping.\n",
 476                                config->name);
 477                         continue;
 478                 }
 479
 480                 if (config->ramdisk &&
 481                     config->ramdisk->compression < 0) {
 482                         printk(BIOS_WARNING, "Ramdisk is compressed with "
 483                                "an unsupported algorithm, discarding config %s."
 484                                "\n", config->name);
 485                         continue;
 486                 }
 487
 488                 if (fit_update_compat(config))
 489                         continue;
 490
 491                 printk(BIOS_DEBUG, "FIT: config %s", config->name);
 492                 if (default_config_name &&
 493                     !strcmp(config->name, default_config_name)) {
 494                         printk(BIOS_DEBUG, " (default)");
 495                         default_config = config;
 496                 }
 497                 printk(BIOS_DEBUG, ", kernel %s", config->kernel->name);
 498                 printk(BIOS_DEBUG, ", fdt %s", config->fdt->name);
 499                 list_for_each(overlay_chain, config->overlays, list_node)
 500                         printk(BIOS_DEBUG, " %s", overlay_chain->overlay->name);
 501                 if (config->ramdisk)
 502                         printk(BIOS_DEBUG, ", ramdisk %s",
 503                                config->ramdisk->name);
 504                 if (config->compat.name) {
 505                         printk(BIOS_DEBUG, ", compat");
 506                         int bytes = config->compat.size;
 507                         const char *compat_str = config->compat.data;
 508                         for (int pos = 0; bytes && compat_str[0]; pos++) {
 509                                 printk(BIOS_DEBUG, " %s", compat_str);
 510                                 if (pos == config->compat_pos)
 511                                         printk(BIOS_DEBUG, " (match)");
 512                                 int len = strlen(compat_str) + 1;
 513                                 compat_str += len;
 514                                 bytes -= len;
 515                         }
 516
 517                         if (config->compat_rank >= 0 && (!compat_config ||
 518                             config->compat_rank > compat_config->compat_rank))
 519                                 compat_config = config;
 520                 }
 521                 printk(BIOS_DEBUG, "\n");
 522         }
 523
 524         struct fit_config_node *to_boot = NULL;
 525         if (compat_config) {
 526                 to_boot = compat_config;
 527                 printk(BIOS_INFO, "FIT: Choosing best match %s for compat "
 528                        "%s.\n", to_boot->name, to_boot->compat_string);
 529         } else if (default_config) {
 530                 to_boot = default_config;
 531                 printk(BIOS_INFO, "FIT: No match, choosing default %s.\n",
 532                        to_boot->name);
 533         } else {
 534                 printk(BIOS_ERR, "FIT: No compatible or default configs. "
 535                        "Giving up.\n");
 536                 return NULL;
 537         }
 538
 539         return to_boot;
 540 }