u-boot/env/nvram.c
Goldschmidt Simon b2cdef4861 env: restore old env_get_char() behaviour
With multiple environments, the 'get_char' callback for env
drivers does not really make sense any more because it is
only supported by two drivers (eeprom and nvram).

To restore single character loading for these drivers,
override 'env_get_char_spec'.

Signed-off-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
2018-02-16 11:12:42 -05:00

122 lines
3 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>
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* 09-18-2001 Andreas Heppel, Sysgo RTS GmbH <aheppel@sysgo.de>
*
* It might not be possible in all cases to use 'memcpy()' to copy
* the environment to NVRAM, as the NVRAM might not be mapped into
* the memory space. (I.e. this is the case for the BAB750). In those
* cases it might be possible to access the NVRAM using a different
* method. For example, the RTC on the BAB750 is accessible in IO
* space using its address and data registers. To enable usage of
* NVRAM in those cases I invented the functions 'nvram_read()' and
* 'nvram_write()', which will be activated upon the configuration
* #define CONFIG_SYS_NVRAM_ACCESS_ROUTINE. Note, that those functions are
* strongly dependent on the used HW, and must be redefined for each
* board that wants to use them.
*/
#include <common.h>
#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#include <search.h>
#include <errno.h>
DECLARE_GLOBAL_DATA_PTR;
#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
extern void *nvram_read(void *dest, const long src, size_t count);
extern void nvram_write(long dest, const void *src, size_t count);
#else
env_t *env_ptr = (env_t *)CONFIG_ENV_ADDR;
#endif
#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
/** Call this function from overridden env_get_char_spec() if you need
* this functionality.
*/
int env_nvram_get_char(int index)
{
uchar c;
nvram_read(&c, CONFIG_ENV_ADDR + index, 1);
return c;
}
#endif
static int env_nvram_load(void)
{
char buf[CONFIG_ENV_SIZE];
#if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
nvram_read(buf, CONFIG_ENV_ADDR, CONFIG_ENV_SIZE);
#else
memcpy(buf, (void *)CONFIG_ENV_ADDR, CONFIG_ENV_SIZE);
#endif
return env_import(buf, 1);
}
static int env_nvram_save(void)
{
env_t env_new;
int rcode = 0;
rcode = env_export(&env_new);
if (rcode)
return rcode;
#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE
nvram_write(CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE);
#else
if (memcpy((char *)CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE) == NULL)
rcode = 1;
#endif
return rcode;
}
/*
* Initialize Environment use
*
* We are still running from ROM, so data use is limited
*/
static int env_nvram_init(void)
{
#if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE)
ulong crc;
uchar data[ENV_SIZE];
nvram_read(&crc, CONFIG_ENV_ADDR, sizeof(ulong));
nvram_read(data, CONFIG_ENV_ADDR + sizeof(ulong), ENV_SIZE);
if (crc32(0, data, ENV_SIZE) == crc) {
gd->env_addr = (ulong)CONFIG_ENV_ADDR + sizeof(long);
#else
if (crc32(0, env_ptr->data, ENV_SIZE) == env_ptr->crc) {
gd->env_addr = (ulong)&env_ptr->data;
#endif
gd->env_valid = ENV_VALID;
} else {
gd->env_addr = (ulong)&default_environment[0];
gd->env_valid = ENV_INVALID;
}
return 0;
}
U_BOOT_ENV_LOCATION(nvram) = {
.location = ENVL_NVRAM,
ENV_NAME("NVRAM")
.load = env_nvram_load,
.save = env_save_ptr(env_nvram_save),
.init = env_nvram_init,
};