[Etherboot-developers] UNDI driver

[Michael B. <mb...@fe...>]

There is now a very-nearly working UNDI driver in 5.1 CVS under
arch/i386/drivers/net.  This driver allows Etherboot to work with any NIC
for which an UNDI option ROM is provided.

The driver does not require Etherboot to be started by chaining from PXE;  
it will scan for an UNDI ROM and initialise it fully from scratch.  I have
been testing by booting from floppy, which works fine.  I imagine that 
PXE-chaining would also work, although I haven't tested it yet.

Note that you cannot yet use the Etherboot UNDI driver to actually boot a
kernel;  although all the routines are working and the driver can get a
DHCP lease and start downloading a file, it dies instantly because the
downloaded file stomps right over the PXE UNDI driver.  In order to fix 
this, I need to sort out a method for allocating base memory in Etherboot.

Question 1: Is there currently any method for allocating base memory?  I
need space for three structures:

1. The PXE UNDI driver code segment (up to 64K, probably 16K)
2. The PXE UNDI driver data segment (up to 64K, probably 16K)
3. Temporary buffers that I can stick data into while calling the 
   real-mode UNDI API (about 2-3K).

I'm currently (as a quick "test-the-driver" method) dumping these at
pseudo-random places in base memory, which works fine up to the point that
a kernel image loads...  :-)


Question 2: I have an assembly routine _undi_call that is a wrapper around 
the real-mode UNDI API calls.  I've placed this in pcbios.S but haven't 
yet checked it in because it seems like a bad place to put it; it would 
end up being compiled in to every Etherboot image, not just the UNDI one.  
Ideally, I'd like to create a file undi_wrapper.S in 
arch/i386/drivers/net and have this linked in.  I suspect I'm going to 
have to edit genrules.pl to achieve this, unless anyone can suggest a 
quick and easy method?


Michael