blob: 39adccabbee106e4eeb5ba30c2e169bd3f4063e2 [file] [log] [blame]
/*
* (C) Copyright 2000-2010
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Andreas Heppel <aheppel@sysgo.de>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
#include <i2c.h>
#endif
#include <search.h>
#include <errno.h>
#include <linux/compiler.h> /* for BUG_ON */
DECLARE_GLOBAL_DATA_PTR;
static int eeprom_bus_read(unsigned dev_addr, unsigned offset,
uchar *buffer, unsigned cnt)
{
int rcode;
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
int old_bus = i2c_get_bus_num();
if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
#endif
rcode = eeprom_read(dev_addr, offset, buffer, cnt);
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
i2c_set_bus_num(old_bus);
#endif
return rcode;
}
static int eeprom_bus_write(unsigned dev_addr, unsigned offset,
uchar *buffer, unsigned cnt)
{
int rcode;
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
int old_bus = i2c_get_bus_num();
if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
#endif
rcode = eeprom_write(dev_addr, offset, buffer, cnt);
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
i2c_set_bus_num(old_bus);
#endif
return rcode;
}
static uchar env_eeprom_get_char(int index)
{
uchar c;
unsigned int off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == ENV_REDUND)
off = CONFIG_ENV_OFFSET_REDUND;
#endif
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off + index + offsetof(env_t, data), &c, 1);
return c;
}
static void env_eeprom_load(void)
{
char buf_env[CONFIG_ENV_SIZE];
unsigned int off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
ulong len, crc[2], crc_tmp;
unsigned int off_env[2];
uchar rdbuf[64], flags[2];
int i, crc_ok[2] = {0, 0};
eeprom_init(-1); /* prepare for EEPROM read/write */
off_env[0] = CONFIG_ENV_OFFSET;
off_env[1] = CONFIG_ENV_OFFSET_REDUND;
for (i = 0; i < 2; i++) {
/* read CRC */
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off_env[i] + offsetof(env_t, crc),
(uchar *)&crc[i], sizeof(ulong));
/* read FLAGS */
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off_env[i] + offsetof(env_t, flags),
(uchar *)&flags[i], sizeof(uchar));
crc_tmp = 0;
len = ENV_SIZE;
off = off_env[i] + offsetof(env_t, data);
while (len > 0) {
int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
rdbuf, n);
crc_tmp = crc32(crc_tmp, rdbuf, n);
len -= n;
off += n;
}
if (crc_tmp == crc[i])
crc_ok[i] = 1;
}
if (!crc_ok[0] && !crc_ok[1]) {
gd->env_addr = 0;
gd->env_valid = 0;
} else if (crc_ok[0] && !crc_ok[1]) {
gd->env_valid = ENV_VALID;
} else if (!crc_ok[0] && crc_ok[1]) {
gd->env_valid = ENV_REDUND;
} else {
/* both ok - check serial */
if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
gd->env_valid = ENV_VALID;
else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
gd->env_valid = ENV_REDUND;
else if (flags[0] == 0xFF && flags[1] == 0)
gd->env_valid = ENV_REDUND;
else if (flags[1] == 0xFF && flags[0] == 0)
gd->env_valid = ENV_VALID;
else /* flags are equal - almost impossible */
gd->env_valid = ENV_VALID;
}
#else /* CONFIG_ENV_OFFSET_REDUND */
ulong crc, len, new;
uchar rdbuf[64];
eeprom_init(-1); /* prepare for EEPROM read/write */
/* read old CRC */
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
CONFIG_ENV_OFFSET + offsetof(env_t, crc),
(uchar *)&crc, sizeof(ulong));
new = 0;
len = ENV_SIZE;
off = offsetof(env_t, data);
while (len > 0) {
int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
CONFIG_ENV_OFFSET + off, rdbuf, n);
new = crc32(new, rdbuf, n);
len -= n;
off += n;
}
if (crc == new) {
gd->env_valid = ENV_VALID;
} else {
gd->env_valid = 0;
}
#endif /* CONFIG_ENV_OFFSET_REDUND */
off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == ENV_REDUND)
off = CONFIG_ENV_OFFSET_REDUND;
#endif
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off, (uchar *)buf_env, CONFIG_ENV_SIZE);
env_import(buf_env, 1);
}
static int env_eeprom_save(void)
{
env_t env_new;
int rc;
unsigned int off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
unsigned int off_red = CONFIG_ENV_OFFSET_REDUND;
char flag_obsolete = OBSOLETE_FLAG;
#endif
rc = env_export(&env_new);
if (rc)
return rc;
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == ENV_VALID) {
off = CONFIG_ENV_OFFSET_REDUND;
off_red = CONFIG_ENV_OFFSET;
}
env_new.flags = ACTIVE_FLAG;
#endif
rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
off, (uchar *)&env_new, CONFIG_ENV_SIZE);
#ifdef CONFIG_ENV_OFFSET_REDUND
if (rc == 0) {
eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
off_red + offsetof(env_t, flags),
(uchar *)&flag_obsolete, 1);
if (gd->env_valid == ENV_VALID)
gd->env_valid = ENV_REDUND;
else
gd->env_valid = ENV_VALID;
}
#endif
return rc;
}
U_BOOT_ENV_LOCATION(eeprom) = {
.location = ENVL_EEPROM,
ENV_NAME("EEPROM")
.get_char = env_eeprom_get_char,
.load = env_eeprom_load,
.save = env_save_ptr(env_eeprom_save),
};