u-boot/common/env_eeprom.c
Tom Rini cd0f4fa1ca Revert "env: fix potential stack overflow in environment functions"
Wolfgang requested this be reverted and Rob agreed after further
discussion.  This was a symptom of a larger problem we need to deal
with.

This reverts commit 60d7d5a631.

Signed-off-by: Tom Rini <trini@ti.com>
2013-04-05 14:55:21 -04:00

292 lines
6.7 KiB
C

/*
* (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>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#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;
env_t *env_ptr;
char *env_name_spec = "EEPROM";
int env_eeprom_bus = -1;
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 (gd->flags & GD_FLG_RELOC) {
if (env_eeprom_bus == -1) {
I2C_MUX_DEVICE *dev = NULL;
dev = i2c_mux_ident_muxstring(
(uchar *)CONFIG_I2C_ENV_EEPROM_BUS);
if (dev != NULL)
env_eeprom_bus = dev->busid;
else
printf("error adding env eeprom bus.\n");
}
if (old_bus != env_eeprom_bus) {
i2c_set_bus_num(env_eeprom_bus);
old_bus = env_eeprom_bus;
}
} else {
rcode = i2c_mux_ident_muxstring_f(
(uchar *)CONFIG_I2C_ENV_EEPROM_BUS);
}
#endif
rcode = eeprom_read(dev_addr, offset, buffer, cnt);
#if defined(CONFIG_I2C_ENV_EEPROM_BUS)
if (old_bus != 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();
rcode = i2c_mux_ident_muxstring_f((uchar *)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;
}
uchar env_get_char_spec(int index)
{
uchar c;
unsigned int off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == 2)
off = CONFIG_ENV_OFFSET_REDUND;
#endif
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off + index + offsetof(env_t, data), &c, 1);
return c;
}
void env_relocate_spec(void)
{
char buf[CONFIG_ENV_SIZE];
unsigned int off = CONFIG_ENV_OFFSET;
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == 2)
off = CONFIG_ENV_OFFSET_REDUND;
#endif
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
off, (uchar *)buf, CONFIG_ENV_SIZE);
env_import(buf, 1);
}
int saveenv(void)
{
env_t env_new;
ssize_t len;
char *res;
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
BUG_ON(env_ptr != NULL);
res = (char *)&env_new.data;
len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
if (len < 0) {
error("Cannot export environment: errno = %d\n", errno);
return 1;
}
env_new.crc = crc32(0, env_new.data, ENV_SIZE);
#ifdef CONFIG_ENV_OFFSET_REDUND
if (gd->env_valid == 1) {
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 == 1)
gd->env_valid = 2;
else
gd->env_valid = 1;
}
#endif
return rc;
}
/*
* Initialize Environment use
*
* We are still running from ROM, so data use is limited.
* Use a (moderately small) buffer on the stack
*/
#ifdef CONFIG_ENV_OFFSET_REDUND
int env_init(void)
{
ulong len, crc[2], crc_tmp;
unsigned int off, off_env[2];
uchar buf[64], flags[2];
int i, crc_ok[2] = {0, 0};
eeprom_init(); /* 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(buf)) ? sizeof(buf) : len;
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
buf, n);
crc_tmp = crc32(crc_tmp, buf, 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;
return 0;
} else if (crc_ok[0] && !crc_ok[1]) {
gd->env_valid = 1;
} else if (!crc_ok[0] && crc_ok[1]) {
gd->env_valid = 2;
} else {
/* both ok - check serial */
if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
gd->env_valid = 1;
else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
gd->env_valid = 2;
else if (flags[0] == 0xFF && flags[1] == 0)
gd->env_valid = 2;
else if (flags[1] == 0xFF && flags[0] == 0)
gd->env_valid = 1;
else /* flags are equal - almost impossible */
gd->env_valid = 1;
}
if (gd->env_valid == 2)
gd->env_addr = off_env[1] + offsetof(env_t, data);
else if (gd->env_valid == 1)
gd->env_addr = off_env[0] + offsetof(env_t, data);
return 0;
}
#else
int env_init(void)
{
ulong crc, len, new;
unsigned off;
uchar buf[64];
eeprom_init(); /* 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(buf)) ? sizeof(buf) : len;
eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
CONFIG_ENV_OFFSET + off, buf, n);
new = crc32(new, buf, n);
len -= n;
off += n;
}
if (crc == new) {
gd->env_addr = offsetof(env_t, data);
gd->env_valid = 1;
} else {
gd->env_addr = 0;
gd->env_valid = 0;
}
return 0;
}
#endif