env/env.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Google, Inc
   4  * Written by Simon Glass <sjg@chromium.org>
   5  */
   6
   7 #include <common.h>
   8 #include <env.h>
   9 #include <env_internal.h>
  10 #include <log.h>
  11 #include <asm/global_data.h>
  12 #include <linux/bitops.h>
  13 #include <linux/bug.h>
  14
  15 DECLARE_GLOBAL_DATA_PTR;
  16
  17 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
  18 void env_fix_drivers(void)
  19 {
  20         struct env_driver *drv;
  21         const int n_ents = ll_entry_count(struct env_driver, env_driver);
  22         struct env_driver *entry;
  23
  24         drv = ll_entry_start(struct env_driver, env_driver);
  25         for (entry = drv; entry != drv + n_ents; entry++) {
  26                 if (entry->name)
  27                         entry->name += gd->reloc_off;
  28                 if (entry->load)
  29                         entry->load += gd->reloc_off;
  30                 if (entry->save)
  31                         entry->save += gd->reloc_off;
  32                 if (entry->erase)
  33                         entry->erase += gd->reloc_off;
  34                 if (entry->init)
  35                         entry->init += gd->reloc_off;
  36         }
  37 }
  38 #endif
  39
  40 static struct env_driver *_env_driver_lookup(enum env_location loc)
  41 {
  42         struct env_driver *drv;
  43         const int n_ents = ll_entry_count(struct env_driver, env_driver);
  44         struct env_driver *entry;
  45
  46         drv = ll_entry_start(struct env_driver, env_driver);
  47         for (entry = drv; entry != drv + n_ents; entry++) {
  48                 if (loc == entry->location)
  49                         return entry;
  50         }
  51
  52         /* Not found */
  53         return NULL;
  54 }
  55
  56 static enum env_location env_locations[] = {
  57 #ifdef CONFIG_ENV_IS_IN_EEPROM
  58         ENVL_EEPROM,
  59 #endif
  60 #ifdef CONFIG_ENV_IS_IN_EXT4
  61         ENVL_EXT4,
  62 #endif
  63 #ifdef CONFIG_ENV_IS_IN_FAT
  64         ENVL_FAT,
  65 #endif
  66 #ifdef CONFIG_ENV_IS_IN_FLASH
  67         ENVL_FLASH,
  68 #endif
  69 #ifdef CONFIG_ENV_IS_IN_MMC
  70         ENVL_MMC,
  71 #endif
  72 #ifdef CONFIG_ENV_IS_IN_NAND
  73         ENVL_NAND,
  74 #endif
  75 #ifdef CONFIG_ENV_IS_IN_NVRAM
  76         ENVL_NVRAM,
  77 #endif
  78 #ifdef CONFIG_ENV_IS_IN_REMOTE
  79         ENVL_REMOTE,
  80 #endif
  81 #ifdef CONFIG_ENV_IS_IN_SATA
  82         ENVL_ESATA,
  83 #endif
  84 #ifdef CONFIG_ENV_IS_IN_SPI_FLASH
  85         ENVL_SPI_FLASH,
  86 #endif
  87 #ifdef CONFIG_ENV_IS_IN_UBI
  88         ENVL_UBI,
  89 #endif
  90 #ifdef CONFIG_ENV_IS_NOWHERE
  91         ENVL_NOWHERE,
  92 #endif
  93 };
  94
  95 static bool env_has_inited(enum env_location location)
  96 {
  97         return gd->env_has_init & BIT(location);
  98 }
  99
 100 static void env_set_inited(enum env_location location)
 101 {
 102         /*
 103          * We're using a 32-bits bitmask stored in gd (env_has_init)
 104          * using the above enum value as the bit index. We need to
 105          * make sure that we're not overflowing it.
 106          */
 107         BUILD_BUG_ON(ENVL_COUNT > BITS_PER_LONG);
 108
 109         gd->env_has_init |= BIT(location);
 110 }
 111
 112 /**
 113  * env_get_location() - Returns the best env location for a board
 114  * @op: operations performed on the environment
 115  * @prio: priority between the multiple environments, 0 being the
 116  *        highest priority
 117  *
 118  * This will return the preferred environment for the given priority.
 119  * This is overridable by boards if they need to.
 120  *
 121  * All implementations are free to use the operation, the priority and
 122  * any other data relevant to their choice, but must take into account
 123  * the fact that the lowest prority (0) is the most important location
 124  * in the system. The following locations should be returned by order
 125  * of descending priorities, from the highest to the lowest priority.
 126  *
 127  * Returns:
 128  * an enum env_location value on success, a negative error code otherwise
 129  */
 130 __weak enum env_location env_get_location(enum env_operation op, int prio)
 131 {
 132         if (prio >= ARRAY_SIZE(env_locations))
 133                 return ENVL_UNKNOWN;
 134
 135         return env_locations[prio];
 136 }
 137
 138
 139 /**
 140  * env_driver_lookup() - Finds the most suited environment location
 141  * @op: operations performed on the environment
 142  * @prio: priority between the multiple environments, 0 being the
 143  *        highest priority
 144  *
 145  * This will try to find the available environment with the highest
 146  * priority in the system.
 147  *
 148  * Returns:
 149  * NULL on error, a pointer to a struct env_driver otherwise
 150  */
 151 static struct env_driver *env_driver_lookup(enum env_operation op, int prio)
 152 {
 153         enum env_location loc = env_get_location(op, prio);
 154         struct env_driver *drv;
 155
 156         if (loc == ENVL_UNKNOWN)
 157                 return NULL;
 158
 159         drv = _env_driver_lookup(loc);
 160         if (!drv) {
 161                 debug("%s: No environment driver for location %d\n", __func__,
 162                       loc);
 163                 return NULL;
 164         }
 165
 166         return drv;
 167 }
 168
 169 __weak int env_get_char_spec(int index)
 170 {
 171         return *(uchar *)(gd->env_addr + index);
 172 }
 173
 174 int env_get_char(int index)
 175 {
 176         if (gd->env_valid == ENV_INVALID)
 177                 return default_environment[index];
 178         else
 179                 return env_get_char_spec(index);
 180 }
 181
 182 int env_load(void)
 183 {
 184         struct env_driver *drv;
 185         int best_prio = -1;
 186         int prio;
 187
 188         for (prio = 0; (drv = env_driver_lookup(ENVOP_LOAD, prio)); prio++) {
 189                 int ret;
 190
 191                 if (!env_has_inited(drv->location))
 192                         continue;
 193
 194                 printf("Loading Environment from %s... ", drv->name);
 195                 /*
 196                  * In error case, the error message must be printed during
 197                  * drv->load() in some underlying API, and it must be exactly
 198                  * one message.
 199                  */
 200                 ret = drv->load();
 201                 if (!ret) {
 202                         printf("OK\n");
 203                         gd->env_load_prio = prio;
 204
 205 #if !CONFIG_IS_ENABLED(ENV_APPEND)
 206                         return 0;
 207 #endif
 208                 } else if (ret == -ENOMSG) {
 209                         /* Handle "bad CRC" case */
 210                         if (best_prio == -1)
 211                                 best_prio = prio;
 212                 } else {
 213                         debug("Failed (%d)\n", ret);
 214                 }
 215         }
 216
 217         /*
 218          * In case of invalid environment, we set the 'default' env location
 219          * to the best choice, i.e.:
 220          *   1. Environment location with bad CRC, if such location was found
 221          *   2. Otherwise use the location with highest priority
 222          *
 223          * This way, next calls to env_save() will restore the environment
 224          * at the right place.
 225          */
 226         if (best_prio >= 0)
 227                 debug("Selecting environment with bad CRC\n");
 228         else
 229                 best_prio = 0;
 230
 231         gd->env_load_prio = best_prio;
 232
 233         return -ENODEV;
 234 }
 235
 236 int env_reload(void)
 237 {
 238         struct env_driver *drv;
 239
 240         drv = env_driver_lookup(ENVOP_LOAD, gd->env_load_prio);
 241         if (drv) {
 242                 int ret;
 243
 244                 printf("Loading Environment from %s... ", drv->name);
 245
 246                 if (!env_has_inited(drv->location)) {
 247                         printf("not initialized\n");
 248                         return -ENODEV;
 249                 }
 250
 251                 ret = drv->load();
 252                 if (ret)
 253                         printf("Failed (%d)\n", ret);
 254                 else
 255                         printf("OK\n");
 256
 257                 if (!ret)
 258                         return 0;
 259         }
 260
 261         return -ENODEV;
 262 }
 263
 264 int env_save(void)
 265 {
 266         struct env_driver *drv;
 267
 268         drv = env_driver_lookup(ENVOP_SAVE, gd->env_load_prio);
 269         if (drv) {
 270                 int ret;
 271
 272                 printf("Saving Environment to %s... ", drv->name);
 273                 if (!drv->save) {
 274                         printf("not possible\n");
 275                         return -ENODEV;
 276                 }
 277
 278                 if (!env_has_inited(drv->location)) {
 279                         printf("not initialized\n");
 280                         return -ENODEV;
 281                 }
 282
 283                 ret = drv->save();
 284                 if (ret)
 285                         printf("Failed (%d)\n", ret);
 286                 else
 287                         printf("OK\n");
 288
 289                 if (!ret)
 290                         return 0;
 291         }
 292
 293         return -ENODEV;
 294 }
 295
 296 int env_erase(void)
 297 {
 298         struct env_driver *drv;
 299
 300         drv = env_driver_lookup(ENVOP_ERASE, gd->env_load_prio);
 301         if (drv) {
 302                 int ret;
 303
 304                 if (!drv->erase)
 305                         return -ENODEV;
 306
 307                 if (!env_has_inited(drv->location))
 308                         return -ENODEV;
 309
 310                 printf("Erasing Environment on %s... ", drv->name);
 311                 ret = drv->erase();
 312                 if (ret)
 313                         printf("Failed (%d)\n", ret);
 314                 else
 315                         printf("OK\n");
 316
 317                 if (!ret)
 318                         return 0;
 319         }
 320
 321         return -ENODEV;
 322 }
 323
 324 int env_init(void)
 325 {
 326         struct env_driver *drv;
 327         int ret = -ENOENT;
 328         int prio;
 329
 330         for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
 331                 if (!drv->init || !(ret = drv->init()))
 332                         env_set_inited(drv->location);
 333                 if (ret == -ENOENT)
 334                         env_set_inited(drv->location);
 335
 336                 debug("%s: Environment %s init done (ret=%d)\n", __func__,
 337                       drv->name, ret);
 338
 339                 if (gd->env_valid == ENV_INVALID)
 340                         ret = -ENOENT;
 341         }
 342
 343         if (!prio)
 344                 return -ENODEV;
 345
 346         if (ret == -ENOENT) {
 347                 gd->env_addr = (ulong)&default_environment[0];
 348                 gd->env_valid = ENV_VALID;
 349
 350                 return 0;
 351         }
 352
 353         return ret;
 354 }
 355
 356 int env_select(const char *name)
 357 {
 358         struct env_driver *drv;
 359         const int n_ents = ll_entry_count(struct env_driver, env_driver);
 360         struct env_driver *entry;
 361         int prio;
 362         bool found = false;
 363
 364         printf("Select Environment on %s: ", name);
 365
 366         /* search ENV driver by name */
 367         drv = ll_entry_start(struct env_driver, env_driver);
 368         for (entry = drv; entry != drv + n_ents; entry++) {
 369                 if (!strcmp(entry->name, name)) {
 370                         found = true;
 371                         break;
 372                 }
 373         }
 374
 375         if (!found) {
 376                 printf("driver not found\n");
 377                 return -ENODEV;
 378         }
 379
 380         /* search priority by driver */
 381         for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
 382                 if (entry->location == env_get_location(ENVOP_LOAD, prio)) {
 383                         /* when priority change, reset the ENV flags */
 384                         if (gd->env_load_prio != prio) {
 385                                 gd->env_load_prio = prio;
 386                                 gd->env_valid = ENV_INVALID;
 387                                 gd->flags &= ~GD_FLG_ENV_DEFAULT;
 388                         }
 389                         printf("OK\n");
 390                         return 0;
 391                 }
 392         }
 393         printf("priority not found\n");
 394
 395         return -ENODEV;
 396 }