[U-Boot-Users] Proposal for patch to configure networkparameters

Ulf Samuelsson ulf at atmel.com
Fri Apr 20 23:35:07 CEST 2007

> In message <024c01c78381$d7866f00$01c4af0a at Glamdring> you wrote:
>> U-Boot has  a number of network parameters like
>> etc.
>> While these can be defined in an "include/configs/<board>.h",
>> it would be nice to be able to define this in a separate file
>> since they are really not board specific.
> Actually these parameters  (and  more,  like  MAC  addresses)  should
> *never* be set at all in the U-Boot configuration. They exist for (1)
> hysterical  reasons  I'm  not  going to explain, and (2) because some
> (paying!) customer insisted on having such a feature.

Why should you care if the customer sets a configuration value at compile
time or dynamically?
By setting things at compile time, you allow the board to boot up,
download a script which gets executed by "autoscr"
This script will sets the REAL values for the network.
Obviously the values should only be used until manually changed.

I.E: if you do

setenv ipaddr

then this should override the  CONFIG_IPADDR value.

Not sure, if this is your problem.

> Normally, you should use other methods to customize your system - the
> U-Boot binary image for a board should always be independent of  such
> settings.

Assume you have no serial communication available...
How do you reconfigure the system?

Can you explain how to download the environment using the network
if you are not allowed to compile in the network parameters?

> There are other, better ways to implement what you want  to  do.  For
> example,  you  can  put  such  information  in a separate location in
> flashand make U-Boot to auto-initialize  these  variable  from  these
> default  settings  in case the environment does not contain any other
> settings yet, etc.

I think that U-Boot needs to test the environment to see if it is valid
or not, and only use these values if environment is invalid.
I do not think that I need to have it in a separate area.
Incidently, if the initial value is in a separate segment, then
you can overwrite this later with other values.

Best Regards
Ulf Samuelsson                ulf at atmel.com
Atmel Nordic AB
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