env/env.c

   1 /*
   2  * Copyright (C) 2017 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <environment.h>
  10
  11 DECLARE_GLOBAL_DATA_PTR;
  12
  13 static struct env_driver *env_driver_lookup(enum env_location loc)
  14 {
  15         struct env_driver *drv;
  16         const int n_ents = ll_entry_count(struct env_driver, env_driver);
  17         struct env_driver *entry;
  18
  19         drv = ll_entry_start(struct env_driver, env_driver);
  20         for (entry = drv; entry != drv + n_ents; entry++) {
  21                 if (loc == entry->location)
  22                         return entry;
  23         }
  24
  25         /* Not found */
  26         return NULL;
  27 }
  28
  29 static enum env_location env_get_default_location(void)
  30 {
  31         if IS_ENABLED(CONFIG_ENV_IS_IN_DATAFLASH)
  32                 return ENVL_DATAFLASH;
  33         else if IS_ENABLED(CONFIG_ENV_IS_IN_EEPROM)
  34                 return ENVL_EEPROM;
  35         else if IS_ENABLED(CONFIG_ENV_IS_IN_FAT)
  36                 return ENVL_FAT;
  37         else if IS_ENABLED(CONFIG_ENV_IS_IN_FLASH)
  38                 return ENVL_FLASH;
  39         else if IS_ENABLED(CONFIG_ENV_IS_IN_MMC)
  40                 return ENVL_MMC;
  41         else if IS_ENABLED(CONFIG_ENV_IS_IN_NAND)
  42                 return ENVL_NAND;
  43         else if IS_ENABLED(CONFIG_ENV_IS_IN_NVRAM)
  44                 return ENVL_NVRAM;
  45         else if IS_ENABLED(CONFIG_ENV_IS_IN_REMOTE)
  46                 return ENVL_REMOTE;
  47         else if IS_ENABLED(CONFIG_ENV_IS_IN_SPI_FLASH)
  48                 return ENVL_SPI_FLASH;
  49         else if IS_ENABLED(CONFIG_ENV_IS_IN_UBI)
  50                 return ENVL_UBI;
  51         else if IS_ENABLED(CONFIG_ENV_IS_NOWHERE)
  52                 return ENVL_NOWHERE;
  53         else
  54                 return ENVL_UNKNOWN;
  55 }
  56
  57 struct env_driver *env_driver_lookup_default(void)
  58 {
  59         enum env_location loc = env_get_default_location();
  60         struct env_driver *drv;
  61
  62         drv = env_driver_lookup(loc);
  63         if (!drv) {
  64                 debug("%s: No environment driver for location %d\n", __func__,
  65                       loc);
  66                 return NULL;
  67         }
  68
  69         return drv;
  70 }
  71
  72 int env_get_char(int index)
  73 {
  74         struct env_driver *drv = env_driver_lookup_default();
  75         int ret;
  76
  77         if (gd->env_valid == ENV_INVALID)
  78                 return default_environment[index];
  79         if (!drv)
  80                 return -ENODEV;
  81         if (!drv->get_char)
  82                 return *(uchar *)(gd->env_addr + index);
  83         ret = drv->get_char(index);
  84         if (ret < 0) {
  85                 debug("%s: Environment failed to load (err=%d)\n",
  86                       __func__, ret);
  87         }
  88
  89         return ret;
  90 }
  91
  92 int env_load(void)
  93 {
  94         struct env_driver *drv = env_driver_lookup_default();
  95         int ret = 0;
  96
  97         if (!drv)
  98                 return -ENODEV;
  99         if (!drv->load)
 100                 return 0;
 101         ret = drv->load();
 102         if (ret) {
 103                 debug("%s: Environment failed to load (err=%d)\n", __func__,
 104                       ret);
 105                 return ret;
 106         }
 107
 108         return 0;
 109 }
 110
 111 int env_save(void)
 112 {
 113         struct env_driver *drv = env_driver_lookup_default();
 114         int ret;
 115
 116         if (!drv)
 117                 return -ENODEV;
 118         if (!drv->save)
 119                 return -ENOSYS;
 120         ret = drv->save();
 121         if (ret) {
 122                 debug("%s: Environment failed to save (err=%d)\n", __func__,
 123                       ret);
 124                 return ret;
 125         }
 126
 127         return 0;
 128 }
 129
 130 int env_init(void)
 131 {
 132         struct env_driver *drv = env_driver_lookup_default();
 133         int ret = -ENOENT;
 134
 135         if (!drv)
 136                 return -ENODEV;
 137         if (drv->init)
 138                 ret = drv->init();
 139         if (ret == -ENOENT) {
 140                 gd->env_addr = (ulong)&default_environment[0];
 141                 gd->env_valid = ENV_VALID;
 142
 143                 return 0;
 144         } else if (ret) {
 145                 debug("%s: Environment failed to init (err=%d)\n", __func__,
 146                       ret);
 147                 return ret;
 148         }
 149
 150         return 0;
 151 }