env: Add generic redundant environment implementation

All current environments that implement redundancy use almost
identical implementations. This patch implements the env_nand
implementation as a function in env_common, and updates the
env_export function to export an env_nand-style 'flags' field by
default.

Signed-off-by: Fiach Antaw <fiach.antaw@uqconnect.edu.au>
Reviewed-by: Tom Rini <trini@konsulko.com>
This commit is contained in:
Fiach Antaw 2017-01-25 18:53:11 +10:00 committed by Tom Rini
parent 845e10d165
commit 76768f5f08
2 changed files with 56 additions and 0 deletions

View File

@ -226,6 +226,53 @@ int env_import(const char *buf, int check)
return 0;
}
#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
static unsigned char env_flags;
int env_import_redund(const char *buf1, const char *buf2)
{
int crc1_ok, crc2_ok;
env_t *ep, *tmp_env1, *tmp_env2;
tmp_env1 = (env_t *)buf1;
tmp_env2 = (env_t *)buf2;
crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
tmp_env1->crc;
crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
tmp_env2->crc;
if (!crc1_ok && !crc2_ok) {
set_default_env("!bad CRC");
return 0;
} else if (crc1_ok && !crc2_ok) {
gd->env_valid = 1;
} else if (!crc1_ok && crc2_ok) {
gd->env_valid = 2;
} else {
/* both ok - check serial */
if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
gd->env_valid = 2;
else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
gd->env_valid = 1;
else if (tmp_env1->flags > tmp_env2->flags)
gd->env_valid = 1;
else if (tmp_env2->flags > tmp_env1->flags)
gd->env_valid = 2;
else /* flags are equal - almost impossible */
gd->env_valid = 1;
}
if (gd->env_valid == 1)
ep = tmp_env1;
else
ep = tmp_env2;
env_flags = ep->flags;
return env_import((char *)ep, 0);
}
#endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */
/* Export the environment and generate CRC for it. */
int env_export(env_t *env_out)
{
@ -247,6 +294,10 @@ int env_export(env_t *env_out)
env_out->crc = crc32(0, env_out->data, ENV_SIZE);
#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
env_out->flags = ++env_flags; /* increase the serial */
#endif
return 0;
}

View File

@ -224,6 +224,11 @@ int env_import(const char *buf, int check);
/* Export from hash table into binary representation */
int env_export(env_t *env_out);
#ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
/* Select and import one of two redundant environments */
int env_import_redund(const char *buf1, const char *buf2);
#endif
#endif /* DO_DEPS_ONLY */
#endif /* _ENVIRONMENT_H_ */