[U-Boot-Users] Re: add new protocol

[Massimiliano Cialdi]

On Wed, 03 Nov 2004 19:16:10 +0100
Wolfgang Denk <wd at denx.de> wrote:

> > We use u-boot 0.4.0 and we need to add new custom network protocol on top of udp.
> 
> Is this just coincidence, or are you by chance working  on  the  same
> project  as  Mastupristi?  who claims he must add support for TCP for
> the very same obsolete version of U-Boot?
Yes, it is the same project. We had persuaded our clients to use the custom protocol on top of udp
instead of tcp.

> > How is it possible? How to read/write udp packets without involve other protocols (RARP, TFTP or BOOTP)?
> You can add your own hooks into the network code.
> But do NOT expect to be able to run anything even remotely similar to TCP.
> 
> > Our custom device need to provide some features (involving our custom protocol) before linux is boot.
> 
> What's the difference who provides the services, U-Boot or Linux? The
> peer probably does not care if it's U-Boot or Linux, or does it?
We don't know what our clients need exactly, and why they want to embed their protocol into u-boot.
We only know that they pay us to make their protocol works into u-boot.
I think that they could use this protocol to test the features of devices before flashing linux. Once the device
has pass all tests they download the compressed linux image in the device's flash using their protocol again.
This is only my guess.

> > please note that since we were asked to use version 0.4.0, we cannot use a newer version of u-boot.
> 
> Don't do it.
> 
> You will not get any help for this obsoleted version.
> 
> Your extension will never have a chance to  make  it  into  a  recent
> version of U-Boot.
> 
> You will suffer from lots of bugs which have been  fixed  in  the  18
> months that have passed since 0.4.0 was released.
> 
> Do yourself and your customer a favour:  Don't  do  it.  Use  current
> code. Use the top of CVS.
Unfortunately in a industrial context (instead of consumer) the "recent versions" are not the answer.
Our clients have started this project months ago. They started with 0.4.0, they test that version and they
patched that version to meet their need. Then they wonder if they can use a more recent version.
The technical answer is: yes, but it's necessary to study new code, rewrite all patches, reimplemnt some algorithm.
Then it's necessary to retest all devices and software to meet all certification request.
Estimated time N weeks (with N>15).
So the commercial answer is: No, we use the old version. Already written, already tested, and already working.

I'm investigating if it is possible to "integrate" patches for 0.4.0 in 1.1.1 in few time, but concurrently I must implement
the protocol.

So, please, help me.
Tell me which files and which functions I need to "touch" to send/receive udp packets.


thanks

-- 
Mastupristi?