Sources for linux kernels for ARMs with MMU

General

For many arm-based devices, there are linux distributions that already include a linux kernel.
If you have a PDA or similar, have a look at http://familiar.handhelds.org/. There you find a linux distribution, of course including a kernel.
If you hava a ARM development board (or evaluation board), your vendor probably has a linux distrubtion for that board.
Of course, not anyone can or wants to stay with the provided kernel. That's where it becomes interesting:

The Linux Kernel Archives

In genernal the main source for linux kernels is http://www.kernel.org/ . The question is: Are these vanilla kernels suited for your ARM board ?

Kernel Series 2.4:

: This kernel is in maintainence mode. This means new features, support for new hardware etc. is not integrated in this kernel series any more. This means that there are several arm-related patches that are not and will not be integrated here. This is a problem especially for new ARM hardware. In fact I do not know any ARM linux distributions that uses vanilla 2.4 kernels.

Kernel Series 2.6:

: This is probably a good choice. Details see below.

The ARM Linux Project - Linux for all ARM based machines

http://www.arm.linux.org.uk/ Unfortunately I did not find a clear statement that this THE official ARM linux site. But it really seems to be that.

Russell King, the person who is listed as responsible for the ARM/STRONGARM110 PORT in the kernel MAINTAINERS file (included in every kernel source) is active there. (this is also the first site listed when you google for arm linux)

This means whenever you look for a kernel for your arm board, this is the place where to look first.

On http://www.arm.linux.org.uk/developer/ you can find links to the linux kernels for series 2.4 and 2.6 (and others).

2.4 Kernels: On http://www.arm.linux.org.uk/developer/v2.4/ you find the linux kernel series v2.4 kernels.

: Kernels up to 2.4.21-rmk2 have the patch-suffix rmk, that means they were made by Russell King. The kernels 2.4.24-vrs1 to 2.4.27-vrs1 have the patch suffix vrs, what means they were made by Vincent Sanders. (Currently (05-07-02) 2.4.27-vrs1 is the latest version, although vanilla 2.4.31 is already available.)

: State of 2.4 ARM Linux Kernels:
: Vincent Sanders: "for any serious new development 2.6 should be used."
: (see http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2005-February/027041.html and http://lists.arm.linux.org.uk/pipermail/linux-arm-kernel/2005-February/thread.html#27031 )

2.6 Kernels: On http://www.arm.linux.org.uk/developer/v2.6/ you find some old linux kernel series v2.6 kernels. But as ftp://ftp.arm.linux.org.uk/pub/armlinux/source/kernel-patches/v2.6/README says:

: As of 2.6.0-rmk2, sufficient patches have been merged into mainline to make the release of -rmk kernels unnecessary. Therefore, there will be no further -rmk patch releases.

: Therefore, please use a recent mainline kernel, where recent is defined as one released within the last two months. Mainline kernels can be found at http://ftp.kernel.org/pub/linux/kernel/v2.6/

: State of 2.6 ARM Linux Kernels:
: Vincent Sanders: "for any serious new development 2.6 should be used."

Many arm linux distributions use the v2.4 kernels from http://www.arm.linux.org.uk or the v2.6 kernels from http://www.kernel.org , often with additional patches specific to their hardware:
- familiar v0.8.2 uses
  - kernel-image-2.4.25-vrs2-pxa1-jpm1
  - kernel-image-2.6.11
  - and others
(see http://familiar.handhelds.org/releases/v0.8.2/feed/base/ )
- atmel AT91 CDROM uses
  - linux-2.4.27-vrs1
(see ftp://at91dist:distrib@81.80.104.162/Linux/ )
- lomx.net uses 2.4.19-rmk6
- ...

arm.linux.org.uk also provides
- arm mailing lists:
http://lists.arm.linux.org.uk/mailman/listinfo/
(list archives and subscription forms)
http://www.arm.linux.org.uk/mailinglists/
(list info)
- a patch tracking system http://www.arm.linux.org.uk/developer/patches/
- docs, faqs, links, etc.

Others

There are hardware-specific patches that have not yet been integrated to the kernels from arm.linux.org.uk :

for atmel at91rm9200: see at91rm9200 drivers

Misc

see also http://www.treblig.org/Linux_kernel_source_finder.html