blob: bcc189e14db71bf178951205410b060ae9ff5da6 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*/
#include <env.h>
#include <env_internal.h>
#include <log.h>
#include <asm/global_data.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/errno.h>
DECLARE_GLOBAL_DATA_PTR;
static struct env_driver *_env_driver_lookup(enum env_location loc)
{
struct env_driver *drv;
const int n_ents = ll_entry_count(struct env_driver, env_driver);
struct env_driver *entry;
drv = ll_entry_start(struct env_driver, env_driver);
for (entry = drv; entry != drv + n_ents; entry++) {
if (loc == entry->location)
return entry;
}
/* Not found */
return NULL;
}
static enum env_location env_locations[] = {
#ifdef CONFIG_ENV_IS_IN_EEPROM
ENVL_EEPROM,
#endif
#ifdef CONFIG_ENV_IS_IN_EXT4
ENVL_EXT4,
#endif
#ifdef CONFIG_ENV_IS_IN_FAT
ENVL_FAT,
#endif
#ifdef CONFIG_ENV_IS_IN_FLASH
ENVL_FLASH,
#endif
#ifdef CONFIG_ENV_IS_IN_MMC
ENVL_MMC,
#endif
#ifdef CONFIG_ENV_IS_IN_NAND
ENVL_NAND,
#endif
#ifdef CONFIG_ENV_IS_IN_NVRAM
ENVL_NVRAM,
#endif
#ifdef CONFIG_ENV_IS_IN_REMOTE
ENVL_REMOTE,
#endif
#ifdef CONFIG_ENV_IS_IN_SPI_FLASH
ENVL_SPI_FLASH,
#endif
#ifdef CONFIG_ENV_IS_IN_UBI
ENVL_UBI,
#endif
#ifdef CONFIG_ENV_IS_NOWHERE
ENVL_NOWHERE,
#endif
};
static bool env_has_inited(enum env_location location)
{
return gd->env_has_init & BIT(location);
}
static void env_set_inited(enum env_location location)
{
/*
* We're using a 32-bits bitmask stored in gd (env_has_init)
* using the above enum value as the bit index. We need to
* make sure that we're not overflowing it.
*/
BUILD_BUG_ON(ENVL_COUNT > BITS_PER_LONG);
gd->env_has_init |= BIT(location);
}
/**
* arch_env_get_location() - Returns the best env location for an arch
* @op: operations performed on the environment
* @prio: priority between the multiple environments, 0 being the
* highest priority
*
* This will return the preferred environment for the given priority.
* This is overridable by architectures if they need to and has lower
* priority than board side env_get_location() override.
*
* All implementations are free to use the operation, the priority and
* any other data relevant to their choice, but must take into account
* the fact that the lowest prority (0) is the most important location
* in the system. The following locations should be returned by order
* of descending priorities, from the highest to the lowest priority.
*
* Returns:
* an enum env_location value on success, a negative error code otherwise
*/
__weak enum env_location arch_env_get_location(enum env_operation op, int prio)
{
if (prio >= ARRAY_SIZE(env_locations))
return ENVL_UNKNOWN;
return env_locations[prio];
}
/**
* env_get_location() - Returns the best env location for a board
* @op: operations performed on the environment
* @prio: priority between the multiple environments, 0 being the
* highest priority
*
* This will return the preferred environment for the given priority.
* This is overridable by boards if they need to.
*
* All implementations are free to use the operation, the priority and
* any other data relevant to their choice, but must take into account
* the fact that the lowest prority (0) is the most important location
* in the system. The following locations should be returned by order
* of descending priorities, from the highest to the lowest priority.
*
* Returns:
* an enum env_location value on success, a negative error code otherwise
*/
__weak enum env_location env_get_location(enum env_operation op, int prio)
{
return arch_env_get_location(op, prio);
}
/**
* env_driver_lookup() - Finds the most suited environment location
* @op: operations performed on the environment
* @prio: priority between the multiple environments, 0 being the
* highest priority
*
* This will try to find the available environment with the highest
* priority in the system.
*
* Returns:
* NULL on error, a pointer to a struct env_driver otherwise
*/
static struct env_driver *env_driver_lookup(enum env_operation op, int prio)
{
enum env_location loc = env_get_location(op, prio);
struct env_driver *drv;
if (loc == ENVL_UNKNOWN)
return NULL;
drv = _env_driver_lookup(loc);
if (!drv) {
debug("%s: No environment driver for location %d\n", __func__,
loc);
return NULL;
}
return drv;
}
int env_load(void)
{
struct env_driver *drv;
int best_prio = -1;
int prio;
if (CONFIG_IS_ENABLED(ENV_WRITEABLE_LIST)) {
/*
* When using a list of writeable variables, the baseline comes
* from the built-in default env. So load this first.
*/
env_set_default(NULL, 0);
}
for (prio = 0; (drv = env_driver_lookup(ENVOP_LOAD, prio)); prio++) {
int ret;
if (!env_has_inited(drv->location))
continue;
printf("Loading Environment from %s... ", drv->name);
/*
* In error case, the error message must be printed during
* drv->load() in some underlying API, and it must be exactly
* one message.
*/
ret = drv->load();
if (!ret) {
printf("OK\n");
gd->env_load_prio = prio;
return 0;
} else if (ret == -ENOMSG) {
/* Handle "bad CRC" case */
if (best_prio == -1)
best_prio = prio;
} else {
debug("Failed (%d)\n", ret);
}
}
/*
* In case of invalid environment, we set the 'default' env location
* to the best choice, i.e.:
* 1. Environment location with bad CRC, if such location was found
* 2. Otherwise use the location with highest priority
*
* This way, next calls to env_save() will restore the environment
* at the right place.
*/
if (best_prio >= 0)
debug("Selecting environment with bad CRC\n");
else
best_prio = 0;
gd->env_load_prio = best_prio;
return -ENODEV;
}
int env_reload(void)
{
struct env_driver *drv;
drv = env_driver_lookup(ENVOP_LOAD, gd->env_load_prio);
if (drv) {
int ret;
printf("Loading Environment from %s... ", drv->name);
if (!env_has_inited(drv->location)) {
printf("not initialized\n");
return -ENODEV;
}
ret = drv->load();
if (ret)
printf("Failed (%d)\n", ret);
else
printf("OK\n");
if (!ret)
return 0;
}
return -ENODEV;
}
int env_save(void)
{
struct env_driver *drv;
drv = env_driver_lookup(ENVOP_SAVE, gd->env_load_prio);
if (drv) {
int ret;
printf("Saving Environment to %s... ", drv->name);
if (!drv->save) {
printf("not possible\n");
return -ENODEV;
}
if (!env_has_inited(drv->location)) {
printf("not initialized\n");
return -ENODEV;
}
ret = drv->save();
if (ret)
printf("Failed (%d)\n", ret);
else
printf("OK\n");
if (!ret)
return 0;
}
return -ENODEV;
}
int env_erase(void)
{
struct env_driver *drv;
drv = env_driver_lookup(ENVOP_ERASE, gd->env_load_prio);
if (drv) {
int ret;
if (!drv->erase) {
printf("not possible\n");
return -ENODEV;
}
if (!env_has_inited(drv->location)) {
printf("not initialized\n");
return -ENODEV;
}
printf("Erasing Environment on %s... ", drv->name);
ret = drv->erase();
if (ret)
printf("Failed (%d)\n", ret);
else
printf("OK\n");
if (!ret)
return 0;
}
return -ENODEV;
}
int env_init(void)
{
struct env_driver *drv;
int ret = -ENOENT;
int prio;
for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
if (!drv->init || !(ret = drv->init()))
env_set_inited(drv->location);
if (ret == -ENOENT)
env_set_inited(drv->location);
debug("%s: Environment %s init done (ret=%d)\n", __func__,
drv->name, ret);
if (gd->env_valid == ENV_INVALID)
ret = -ENOENT;
}
if (!prio)
return -ENODEV;
if (ret == -ENOENT) {
gd->env_addr = (ulong)&default_environment[0];
gd->env_valid = ENV_VALID;
return 0;
}
return ret;
}
int env_select(const char *name)
{
struct env_driver *drv;
const int n_ents = ll_entry_count(struct env_driver, env_driver);
struct env_driver *entry;
int prio;
bool found = false;
printf("Select Environment on %s: ", name);
/* search ENV driver by name */
drv = ll_entry_start(struct env_driver, env_driver);
for (entry = drv; entry != drv + n_ents; entry++) {
if (!strcmp(entry->name, name)) {
found = true;
break;
}
}
if (!found) {
printf("driver not found\n");
return -ENODEV;
}
/* search priority by driver */
for (prio = 0; (drv = env_driver_lookup(ENVOP_INIT, prio)); prio++) {
if (entry->location == env_get_location(ENVOP_LOAD, prio)) {
/* when priority change, reset the ENV flags */
if (gd->env_load_prio != prio) {
gd->env_load_prio = prio;
gd->env_valid = ENV_INVALID;
gd->flags &= ~GD_FLG_ENV_DEFAULT;
}
printf("OK\n");
return 0;
}
}
printf("priority not found\n");
return -ENODEV;
}