[fedora-arm] How to get started?

[Chris Tyler]

On Tue, 2010-07-13 at 16:49 +1000, Andrew van der Stock wrote:
> Hi there,
> 
> I've offered to help with the OLPC ARM port for OLPC 1.75. Obviously
> this hardware doesn't exist yet, so I have a few questions. 
> 
> I've just installed x64 F13 and got a Fedora account. 
> 
> 1. How is the best way to get started? 
> 2. Should I get a cross-compiler going, and pick a package to port?
> Obviously, I'd prefer to work on the packages that OLPC 1.75 will
> need, but am happy to work on anything you need.
> 3. How can I test the resulting RPM? 
> 4. I'm going to be in the US next week for OSCON. I will try to pick
> up a Beagle Board or GuruPlug, but it seems like supply is severely
> constrained for any / all of the suitable ARM boards. As the OLPC 1.75
> and XO-3 will use Marvell parts, will ARM-A8 boards be a suitable
> target, or should I go with a Marvell based device?
> 
> I have long lost experience with kernel programming (porting Reiserfs
> and other ports to Alpha back in 2000 or so, when LP big endian 64 bit
> was very rare), X11 drivers (Matrox cards) for XFree86 back in the
> 1990's and pnm2ppa - a printer driver for HP's worst ever printers. 
> 
> thanks,
> Andrew
> 
> p.s. I have three XO-1's, but obviously these are not that useful for
> this effort unless parity is achieved for the OS with the 1.75. 

Hi Andrew,

Welcome to the arm list :-)

Here's the current status:

- There is an F12 arm port available
(http://fedoraproject.org/wiki/Architectures/ARM) from a previous
initiative on hardware run by Lennert in NL. F12-arm runs well on a wide
range of hardware, including BeagleBoards, SheevaPlugs, GuruPlugs, and
so forth. However, this port includes a subset of packages and no
updates.

- We're now working on an F13+ port via the koji instance at
http://arm.koji.fedoraproject.org. You can access this system using the
same credentials as you would use to access the primary-arch koji
systems. It includes 12 builders on a good day - 7 here at Seneca in
Toronto and 5 at OLPC in Boston (I say "on a good day" because we're
having troubles with a few of them yet), with a target of 20+ builders
when hardware is available.

- The intention is to have the arm koji instance shadow the primary
archs, so that as packages are built for the primary archs they're also
built for arm, using Dennis Gilmore's koji-shadow script.

A few of the quickest ways to get involved:

- Start fixing up packages that don't build successfully for arm.
http://fedoraproject.org/wiki/Architectures/ARM/Packages_needing_patching contains a list of 44 packages that we know were patched for the F12 initiative and the patches were not upstreamed -- so the F13 and rawhide packages need to be re-patched and the patches need to be checked in to the Fedora CVS (or the upstream projects). Fortunately, we have the diffs from the previous work. Other packages will be added to this list as we encounter build failures with F13.

- Help build a collection of nicely-featured kernels for various
devices.

If you're buying hardware, a Cortex A8 or A9 device such as a
BeagleBoard is fine, but as you note the Marvell parts may give a better
indication of issues we may find on the XOs (e.g., alignment traps, math
performance). The current arch target is armv5te.

--
Chris