Processors

Here is a list of different processor families, with miscellaneous notes for development information:

See also Hardware Hacking for a list of systems that include these processors.

ARM
See ARM website and the Wikipedia ARM article for information about the ARM architecture and processor family.

From the Linux perspective, there are 2 very different kinds of ARM chips: (FIXME: indicate whether or not each chip has a MMU)
 * ARM devices that include a MMU, and can run standard Linux
 * ARM devices without a MMU, which cannot run standard Linux. However, they can run uClinux. The Linux/Microcontroller project is a port of Linux to systems without a Memory Management Unit (MMU), such as the ARM7TDMI and the Microblaze. ( http://uclinux.org/ ).

Please note that because of security considerations for MMU-less processors, it is unwise to use them when 3rd-party or untrusted code will be running on the device. For locked-down, single function devices, MMU-less processors may be appropriate. They are usually less expensive than processors with MMU.

Some major ARM platforms/SOCs are:
 * DaVinci from Texas Instruments
 * OMAP - by TI
 * i.MX - by FreeScale
 * Freescale's GIT repository for i.MX Linux support is at: http://opensource.freescale.com
 * Info about this repository, as of April 2007 is at: http://www.spinics.net/lists/arm-kernel/msg39771.html
 * ARM RealView platforms - by ARM Ltd.
 * Linux BSP and resources available at http://www.arm.com/linux with associated GIT tree
 * XScale/PXA - by Marvell (formerly Intel) -- has MMU
 * Linux BSPs available in mainline kernel or from Marvell web-site (for Monahans)
 * Orion - by Marvell
 * Linux BSP for Orion-2 SoC available on ARM Linux Mailing List.
 * Philips LPC21xx series of ARM processors are currently the lowest-cost ARM processors available. But they have no MMU.
 * JuiceBox uses a ARM S3C44B0X. It runs uClinux.
 * Atmel AT91RM9200 -- has MMU.

MIPS
need info here

SH
need info here

x86
need info here