[U-Boot-Users] environment not being used

Wolfgang Denk wd at denx.de
Sat Jan 31 18:12:47 CET 2004

In message <1075423717.18221.233.camel at localhost.localdomain> you wrote:
> To get around this, we have a small program which is stored in FPGA
> bitstream and runs in FPGA on-chip memory (called BRAM). This program
> copies u-boot binary image from flash to sdram and jumps to it. This
> allows U-boot to run. However the problem is that the environment
> variables saved in flash are not being used even though U-boot has been
> configured with the CFG_ENV_IS_IN_FLASH option turned on. 
> CFG_FLASH_BASE has been set to the flash base address of u-boot and when
> I use saveenv the environment is saved at the proper offset
> CFG_ENV_OFFSET. The only thing thats a bit different for my U-boot
> configuration is that CFG_MONITOR_BASE is set to the sdram base address
> where U-boot starts executing from instead of being set to

Normally U-Boot attempts to read the environment when  starting  from
the same position in memory where it will save it to when you issue a
"saveenv"  command.  You  will  have  to  modify U-Boot such that the
initialization reads from the "fixed" copy in  RAM,  while  "saveenv"
saves to the address in flash, performing the 16-bit-expansion needed
for  your  setup. It seems obvious that a plain copy as usuall cannot
work on your system.

Best regards,

Wolfgang Denk

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Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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