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 int env_load(void)
 170 {
 171         struct env_driver *drv;
 172         int best_prio = -1;
 173         int prio;
 174
 175         for (prio = 0; (drv = env_driver_lookup(ENVOP_LOAD, prio)); prio++) {
 176                 int ret;
 177
 178                 if (!env_has_inited(drv->location))
 179                         continue;
 180
 181                 printf("Loading Environment from %s... ", drv->name);
 182                 /*
 183                  * In error case, the error message must be printed during
 184                  * drv->load() in some underlying API, and it must be exactly
 185                  * one message.
 186                  */
 187                 ret = drv->load();
 188                 if (!ret) {
 189                         printf("OK\n");
 190                         gd->env_load_prio = prio;
 191
 192 #if !CONFIG_IS_ENABLED(ENV_APPEND)
 193                         return 0;
 194 #endif
 195                 } else if (ret == -ENOMSG) {
 196                         /* Handle "bad CRC" case */
 197                         if (best_prio == -1)
 198                                 best_prio = prio;
 199                 } else {
 200                         debug("Failed (%d)\n", ret);
 201                 }
 202         }
 203
 204         /*
 205          * In case of invalid environment, we set the 'default' env location
 206          * to the best choice, i.e.:
 207          *   1. Environment location with bad CRC, if such location was found
 208          *   2. Otherwise use the location with highest priority
 209          *
 210          * This way, next calls to env_save() will restore the environment
 211          * at the right place.
 212          */
 213         if (best_prio >= 0)
 214                 debug("Selecting environment with bad CRC\n");
 215         else
 216                 best_prio = 0;
 217
 218         gd->env_load_prio = best_prio;
 219
 220         return -ENODEV;
 221 }
 222
 223 int env_reload(void)
 224 {
 225         struct env_driver *drv;
 226
 227         drv = env_driver_lookup(ENVOP_LOAD, gd->env_load_prio);
 228         if (drv) {
 229                 int ret;
 230
 231                 printf("Loading Environment from %s... ", drv->name);
 232
 233                 if (!env_has_inited(drv->location)) {
 234                         printf("not initialized\n");
 235                         return -ENODEV;
 236                 }
 237
 238                 ret = drv->load();
 239                 if (ret)
 240                         printf("Failed (%d)\n", ret);
 241                 else
 242                         printf("OK\n");
 243
 244                 if (!ret)
 245                         return 0;
 246         }
 247
 248         return -ENODEV;
 249 }
 250
 251 int env_save(void)
 252 {
 253         struct env_driver *drv;
 254
 255         drv = env_driver_lookup(ENVOP_SAVE, gd->env_load_prio);
 256         if (drv) {
 257                 int ret;
 258
 259                 printf("Saving Environment to %s... ", drv->name);
 260                 if (!drv->save) {
 261                         printf("not possible\n");
 262                         return -ENODEV;
 263                 }
 264
 265                 if (!env_has_inited(drv->location)) {
 266                         printf("not initialized\n");
 267                         return -ENODEV;
 268                 }
 269
 270                 ret = drv->save();
 271                 if (ret)
 272                         printf("Failed (%d)\n", ret);
 273                 else
 274                         printf("OK\n");
 275
 276                 if (!ret)
 277                         return 0;
 278         }
 279
 280         return -ENODEV;
 281 }
 282
 283 int env_erase(void)
 284 {
 285         struct env_driver *drv;
 286
 287         drv = env_driver_lookup(ENVOP_ERASE, gd->env_load_prio);
 288         if (drv) {
 289                 int ret;
 290
 291                 if (!drv->erase)
 292                         return -ENODEV;
 293
 294                 if (!env_has_inited(drv->location))
 295                         return -ENODEV;
 296
 297                 printf("Erasing Environment on %s... ", drv->name);
 298                 ret = drv->erase();
 299                 if (ret)
 300                         printf("Failed (%d)\n", ret);
 301                 else
 302                         printf("OK\n");
 303
 304                 if (!ret)
 305                         return 0;
 306         }
 307
 308         return -ENODEV;
 309 }
 310
 311 int env_init(void)
 312 {
 313         struct env_driver *drv;
 314         int ret = -ENOENT;
 315         int prio;
 316
 317         for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
 318                 if (!drv->init || !(ret = drv->init()))
 319                         env_set_inited(drv->location);
 320                 if (ret == -ENOENT)
 321                         env_set_inited(drv->location);
 322
 323                 debug("%s: Environment %s init done (ret=%d)\n", __func__,
 324                       drv->name, ret);
 325
 326                 if (gd->env_valid == ENV_INVALID)
 327                         ret = -ENOENT;
 328         }
 329
 330         if (!prio)
 331                 return -ENODEV;
 332
 333         if (ret == -ENOENT) {
 334                 gd->env_addr = (ulong)&default_environment[0];
 335                 gd->env_valid = ENV_VALID;
 336
 337                 return 0;
 338         }
 339
 340         return ret;
 341 }
 342
 343 int env_select(const char *name)
 344 {
 345         struct env_driver *drv;
 346         const int n_ents = ll_entry_count(struct env_driver, env_driver);
 347         struct env_driver *entry;
 348         int prio;
 349         bool found = false;
 350
 351         printf("Select Environment on %s: ", name);
 352
 353         /* search ENV driver by name */
 354         drv = ll_entry_start(struct env_driver, env_driver);
 355         for (entry = drv; entry != drv + n_ents; entry++) {
 356                 if (!strcmp(entry->name, name)) {
 357                         found = true;
 358                         break;
 359                 }
 360         }
 361
 362         if (!found) {
 363                 printf("driver not found\n");
 364                 return -ENODEV;
 365         }
 366
 367         /* search priority by driver */
 368         for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
 369                 if (entry->location == env_get_location(ENVOP_LOAD, prio)) {
 370                         /* when priority change, reset the ENV flags */
 371                         if (gd->env_load_prio != prio) {
 372                                 gd->env_load_prio = prio;
 373                                 gd->env_valid = ENV_INVALID;
 374                                 gd->flags &= ~GD_FLG_ENV_DEFAULT;
 375                         }
 376                         printf("OK\n");
 377                         return 0;
 378                 }
 379         }
 380         printf("priority not found\n");
 381
 382         return -ENODEV;
 383 }