env, eeprom: add redundant environment support
Add redundant environment support for environment lying on a EEPROM.
Tested on uppcoming suen3 support
Signed-off-by: Andreas Huber <andreas.huber@keymile.com>
diff --git a/common/env_eeprom.c b/common/env_eeprom.c
index 30de4e9..95a7d0d 100644
--- a/common/env_eeprom.c
+++ b/common/env_eeprom.c
@@ -32,6 +32,11 @@
#include <i2c.h>
#endif
+#ifdef CONFIG_ENV_OFFSET_REDUND
+#define ACTIVE_FLAG 1
+#define OBSOLETE_FLAG 0
+#endif
+
DECLARE_GLOBAL_DATA_PTR;
env_t *env_ptr = NULL;
@@ -93,9 +98,15 @@
uchar env_get_char_spec (int index)
{
uchar c;
+ unsigned int off;
+ 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,
- CONFIG_ENV_OFFSET+index+offsetof(env_t,data),
+ off + index + offsetof(env_t,data),
&c, 1);
return (c);
@@ -103,18 +114,52 @@
void env_relocate_spec (void)
{
+ 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,
- CONFIG_ENV_OFFSET,
+ off,
(uchar*)env_ptr,
CONFIG_ENV_SIZE);
}
int saveenv(void)
{
- return eeprom_bus_write (CONFIG_SYS_DEF_EEPROM_ADDR,
- CONFIG_ENV_OFFSET,
+ 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;
+ if (gd->env_valid == 1) {
+ off = CONFIG_ENV_OFFSET_REDUND;
+ off_red = CONFIG_ENV_OFFSET;
+ }
+
+ env_ptr->flags = ACTIVE_FLAG;
+#endif
+
+ rc = eeprom_bus_write (CONFIG_SYS_DEF_EEPROM_ADDR,
+ off,
(uchar *)env_ptr,
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;
}
/************************************************************************
@@ -123,6 +168,82 @@
* 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;
+ ulong crc[2], crc_tmp;
+ unsigned int off, off_env[2];
+ uchar buf[64];
+ int crc_ok[2] = {0,0};
+ unsigned char flags[2];
+ int i;
+
+ 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;
@@ -159,3 +280,5 @@
return (0);
}
+#endif
+