[U-Boot-Users] auto-save environment if using default environment?

Markus Klotzbücher mk at denx.de
Wed Mar 26 08:28:39 CET 2008


Aras Vaichas <arasv at magtech.com.au> writes:

> Wolfgang Wegner wrote:
>> On our board we have an FPGA, and for different applications a different
>> FPGA file shall be loaded without updating the firmware. For this, the
>> application has to set an U-Boot environment variable that specifies which
>> FPGA file to load on next boot.
>>   
> We use an i2c EEPROM to hold board specific information. I read the
> EEPROM from U-Boot and set up the MAC address and arch/mach number using
> the misc_init_r(void) call method. This separates the U-boot environment
> from the machine specific data. I also use the EEPROM to hold the SDRAM
> settings so the first bootloader can configure the DRAM on multiple
> boards without requiring multiple binaries.
>
> I have a strange bootcmd. If U-Boot starts with a corrupted environment,
> it runs the default bootcmd. The default bootcmd creates a bootcmd and
> then runs saveenv so the next boot will run the new bootcmd..

Nice :-) That does the trick without any modifications to the
code. Though I have to agree with Wolfgang that this could be
potentially dangerous. If for any reason U-Boot went into some kind of
endless restart - saveenv loop...

Best regards

Markus Klotzbuecher

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