Name Size
Parent Directory -
Makefile 1k
bootkernel/ -
This framework supports Linux on several single board computers
| bootkernel | Boot kernel image with integral initramfs |
| example | Example application |
| include | Include files |
| libs | Application libraries |
| linux | Kernel source staging area |
| scripts | Miscellaneous scripts |
| u-boot | Das U-Boot boot loader customizations |
The application libraries are required for the example application but are not required for the boot kernel image.
Build a bootkernel and an example application with something like make BeagleBoard_xM|GadgetPC|SAM9_L9260
I use the prebuilt Code Sourcery g++ Lite glibc toolchains. I have also done a limited amount of testing with the prebuilt DENX ELDK glibc toolchains.
I have not gotten any uClibc toolchain to work satisfactorily, and I no longer have any enthusiasm for rolling my own Linux toolchain, either from the ground up or via Crosstool-ng or BuildRoot.
I have confined my research to boards capable of acting as USB devices (thus excluding otherwise interesting boards such as the Linux Stamp), using the Linux USB gadget drivers. Linux and Windows hosts support such a board configured as either a USB serial port or as a USB network device. My framework allows either and is selected by a u-boot environment variable passed in the kernel command line. Most of my testing is done with the USB network device option.
The Bipom GadgetPC is available from Microcontroller Shop for USD $99. It is an interesting minimalist board with one USB device port, through which power is obtained, and 4 USB host ports. These 5 USB ports comprise the entire I/O capability of the device, other than the TTL level serial console header. The GadgetPC has a 200 MHz AT92SAM9260 ARM processor, 8 MB of DataFlash and 32 MB of RAM.
Tested with kernel 3.0.22 on 22 February 2012.
The Olimex SAM_L9260 is available from the Microcontroller Shop for USD $200. It has one RS-232 serial console port (also with male pins), one USB device port, one USB host port, Ethernet, and 20-pin JTAG and 10-pin UEXT headers. It also has GPIO and expansion header pads (but no pins). The SAM9_L9260 board has a 200 MHz AT92SAM9260 ARM processor, 512 MB of nand flash, and 64 MB of RAM. Interestingly, my board has both nand flash and a 2 MB AT45DB161 serial dataflash containing u-boot. Olimex's advertising materials do not mention the dataflash, but it is described in the SAM9_L9260 user manual.
The SAM9_L9260 proved to be the easiest board to work with, with good support in the mainline Linux kernel, and good I/O capabilities. Unlike any of the other boards, it also has full size SD/MMC and USB type B connectors. Although the most expensive board reviewed here, it just works.
Tested with kernel 3.0.22 on 22 February 2012.
The BeagleBoard_xM is available from Digi-Key for USD $149 (when it is in stock; it is a very hot item!). This promises to be an astounding embedded Linux board for the price. It has a 1 GHz DM3730 Cortex-A8 ARM processor and 512 MB of RAM. It has no flash, and is unique in my experience in that it boots entirely, including hardware bootstrap and u-boot, from an SDHC micro-SD card. It has an RS232 serial console port (with female pins!), one USB device port, 4 USB host ports, Ethernet, DVI (HDMI connector) and S-video outputs, and audio input and output. It also has expansion connectors and/or pads for GPIO, camera, LCD panel, and JTAG.
Mainline kernel support for the BeagleBoard_xM does not appear to be quite as ripe as that for the AT91SAM9260 boards. At this point I have it booting to a serial console login with working USB host and device ports and Ethernet, but some devices are not yet working.
Tested with kernel 2.6.38.8 on 9 June 2011.
Although the low cost/low power Linux board market appears to be dominated by the Atmel AT91SAM9260 processor and its variations, I am also interested in the following boards with other processors:
$Id: README.html 3598 2012-02-22 11:38:15Z svn $
I am available for custom system development (hardware and software) of products based on the AT91SAM9260 or other processors.