[U-Boot] U-boot Config Parameters on Compact Flash

[Dach Miroslaw]

Hello Wolfgang,

Thank you for your quick answer.

>What do you mean my "u-boot parameters"?

To be clear I mean u-boot parameters the environment variables which are denied for example:
CFG_ENV_IS_IN_FLASH 
or
CFG_ENV_IS_IN_EEPROM

>Note however that the opposite direction is harder: there is no FAT
>write support.
>
>OK, you can read  and write raw sectors, but this is obviously less
>flexible (but has the charming benefit to work out of the box).

My new board does not have Flash nor EEPROM. It has only Compact Flash. What would be than your suggestion 
to access (read/write) u-boot (parameters) environ variables?

When the board is booted than at first the simply boot loader which is in Xilinx internal BRAM can 
place u-boot environ variables from file (on Compact Flash) to the RAM memory and next u-boot can be booted.
In such a scenario u-boot can access easily parameters from RAM. The problem remains valid how to write theses environ variables back to the file on Compact Flash.  

Best Regards

Miroslaw Dach

-----Original Message-----
From: Wolfgang Denk [mailto:wd at denx.de]
Sent: Thu 1/20/2011 1:09 PM
To: Dach Miroslaw
Cc: u-boot at lists.denx.de
Subject: Re: [U-Boot] U-boot Config Parameters on Compact Flash
 
Dear "Dach Miroslaw",

In message <1B4F8000449511488D1A640DD6DECA350392A606 at MAILBOX0A.psi.ch> you wrote:
> 
> Compact Flash has few partitions (ie. FAT and EXT2).
> Is it possible to configure u-boot to access (ie. read/write) u-boot parameters which are on Compact Flash as a file?

What do you mean my "u-boot parameters"?

Of course you can for example read a file from a FAT file system on
the CF card, and then import the environment from this.

Note however that the opposite direction is harder: thre is no FAT
write support.

OK, you can read  and write raw sectors, but this is obviously less
flexible (but has the charming benefit to work out of the box).

Best regards,

Wolfgang Denk

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