[U-Boot-Users] Excluding Env Variable section from the u-boot.bin

Nuno João (Ext_NBS) nuno.joao-ext_nbs at siemens.com
Thu Jan 12 13:56:25 CET 2006

	I have a configuration in 2 of "my" boards where the environment
	variable's area lays in a different sector from u-boot code,
	also so that it is possible to upgrade u-boot while keeping
	the environment:

In mpc8xx board I have:

 * Environment in flash. It will be on the flash's 3rd 64KB block, fully
 * using it. U-boot will use the 1st two 64KB blocks, as specified by
#define CFG_ENV_IS_IN_FLASH     1
#define CFG_ENV_OFFSET          0x20000 /*   Offset   of Environment Sector     */
#define CFG_ENV_SIZE            0x10000 /* Total Size of Environment Sector     */

In a mpc85xx board I have:

 * Environment
#define CFG_ENV_IS_IN_FLASH     1
#define CFG_ENV_SECT_SIZE       0x40000     /* 256K (one sector) for env */
/* env in its own flash sector, right before u-boot */
#define CFG_ENV_SIZE            CFG_ENV_SECT_SIZE
#define CFG_ENV_ADDR            0xffe00000

	I didn't need to change anything else. There are some preprocessor
	macros in the environment code that will handle most of the job.


-----Original Message-----
From: u-boot-users-admin at lists.sourceforge.net [mailto:u-boot-users-admin at lists.sourceforge.net] On Behalf Of Albert David
Sent: quinta-feira, 12 de Janeiro de 2006 11:27
To: u-boot-users at lists.sourceforge.net
Subject: [U-Boot-Users] Excluding Env Variable section from the u-boot.bin

For my ppc405EP based custom board I would like to make few changes to
the u-boot memory map, so that every time I update the u-boot,
environment variables in the flash remain untouched.


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