[U-Boot-Users] Reset doesn't work on the 440EP Bamboo reference board

Stefan Roese sr at denx.de
Tue Sep 13 08:45:34 CEST 2005

Hi Youngchul,

On Tuesday 13 September 2005 06:30, Youngchul Bang wrote:
> I have been trying to get U-Boot and Linux running on the AMCC 440EP
> "Bamboo" reference board.  Most U-Boot commands are working.  However,
> I've got problems about reset command and switch.

I just checked this problem with our bamboo board and a current U-Boot 
version: No problem here:

Hit any key to stop autoboot:  0
=> reset

U-Boot 1.1.4 (Aug 24 2005 - 11:12:52)

AMCC PowerPC 440EP Rev. B
Board: Bamboo - AMCC PPC440EP Evaluation Board
        VCO: 800 MHz
        CPU: 400 MHz
        PLB: 100 MHz
        OPB: 50 MHz
        EPB: 25 MHz
I2C:   ready
DRAM:  192 MB
PCI:   Bus Dev VenId DevId Class Int
In:    serial
Out:   serial
Err:   serial
NAND:  64 MB

Type "run flash_nfs" to mount root filesystem over NFS

Hit any key to stop autoboot:  0

> First, reset command does not work except after cp.b command performed
> (i.e. cp.b 100000 fff80000 80000).  I don't know why it works well
> after cp.b command.  Reboot command in Linux doesn't work neither.
> U-Boot version is 1.1.3 and Linux kernel is 2.6.13.  Is it related to
> the same reason?

Hmmm. U-Boot version 1.1.3 covers over 1/2 year of code versions. Please use 
the current version (top cvs) and give it a nother try. As you may have 
noticed, the AMCC 4xx boards have received a major cleanup in the last weeks.

> Second, the reset switch does not work.  I've been confirmed that
> SYSTEM_RESET line is getting pulled down when I push the reset switch.

Do I understand this right: You push the reset button, and the board does not 
reset! Strange.

> When I try to get PIBS instead of U-Boot on the same board, the above
> problems haven't happened.
> Had the problems been discussed before in this list?  I can't find any
> of conversations about them.  If so, give me the url please.


> Let me know how to fix them up.

See above. Try the current version and let me know, if the problem still 

Another question: Do you have a debugger connected while resetting the board?

Best regards,

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