xscale port of fedora core 2

[Lennert Buytenhek]

On Tue, Aug 10, 2004 at 09:06:44PM +1000, Russell Coker wrote:

> > Some weeks ago, I started porting Fedora Core 2 to the Intel IXP2400,
> > which is basically a 600MHz big-endian xscale (ARM) core.  Right now
> > I have ~550 out of ~950 packages building and seemingly in good order.
> > (I have not yet attempted to build openoffice and such.)
> 
> Is anyone making machines for general-purpose use based on the
> IXP2400 core?  Or is it just for routers?

[ For those not in the know: the IXP2400 is basically just an xscale
  (which is Intel's version of ARM) processor, with some extra on-chip
  processing logic for fast network processing.  The chip itself has
  an integrated memory controller, 64b/66MHz PCI unit, 4Gbps SPI-3 bus,
  and 8 on-chip processors which have a very simple instruction set
  designed to do network-related things such as switching, routing,
  firewalling, etc.  It can do full wire speed 4xGbps processing, and
  its bigger brother, the IXP2800, does full wire speed 10xGbps.  ]

I'm not aware of any general-purpose machines based on the IXP2400
or IXP2800 as of yet.  There are a number of commercially available
switches and routers that have it under the hood, and there are
three development kits that I know of.

http://www.intel.com/design/network/products/npfamily/ixdp24xx.htm
http://www.intel.com/design/network/products/npfamily/ixdp28xx.htm
http://www.radisys.com/oem_products/ds-page.cfm?productdatasheetsid=1147

We're thinking about having an ATX form factor board designed for it,
which would be perfectly well possible since the chip has basically
everything you'd need in a general purpose PC.  But no definite plans
on that yet.

My motivation for porting Fedora to it was thus: most people who use
the IXP2400 run some form of Montavista on it, but considering that
these processors run at 600MHz or 700MHz and typically have between
256MB and 1GB of RAM, why not run a normal distro on it?  I'm used
to RH/FC, and I want to have all the tools I have available on my
desktop box on my 'embedded' platform as well.

Even though the IXP2400 is a bit of a niche processor, the xscale is
much more widely used, and I think that a port of Fedora to the xscale
would be a generally good idea.  Especially considering that the number
of required patches is small.


> > I would like to start submitting the (surprisingly small number of)
> > needed patches so far back into Fedora, perhaps shifting my efforts
> > towards FC3.  What do people here think about such an effort?
> 
> Sounds good.  Any time you port to a new architecture you are likely to
> shake out bugs that aren't obvious on i386.  I've found heaps of bugs
> by porting code to other CPUs.

Yeah.  There are lots of strange things to be found in userland.  Like
openssl assuming that linux-elf == i386, for example.

OK, so how do I go from here?  Should I just submit all my patches to
bugzilla and wait?


> Also there's a good chance that bugs you fix for ARM may also impact IA64.

Perhaps so.


--L