Looking for some help finding a small embedded linux board that meets a few basic requirements. I've been able to find some things that are close, but nothing that really fits properly and I'm hoping for some suggestions I've not seen or considered already.
Current requirements are as follows.
Software:
Mainline linux kernel. I should be able to use git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git and be able to build a working kernel for the device including all critical hardware drivers without needing any external patches or vendor trees. All drivers for critical hardware must be fully functional. I'll only consider relaxing this requirement if there's a good well organised community that are obviously actively working to merge the necessary code into the mainline kernel.
Hardware:
Arm cpu preferred, but not essential. Something roughly equivalent to a Cortex A8 or better. Would consider MIPS or other alternatives as well. Single core.
Minimum 256MB ram available for linux. If something else on the SoC is stealing ram for it's own use then an equivalent increase in physical ram is required.
Hardware assisted SPI controller. Bit-bang is not acceptable.
Hardware assisted I2C controller. Bit-bang is not acceptable.
Approx 16 interrupt capable GPIO pins. These must be in addition to the SPI/I2C, shared alternate functions with the I2C/SPI are not acceptable.
Ethernet. Need not be fast, 10Mb/s would suffice. Native ethernet preferred, usb as a last resort.
RS232 port.
Boot from micro-sd card. Native sdhci controller capable of 1.8v operation with associated speed modes.
All hardware interfaces need to be made available on a cheap, easy to use connector. Boards with connectors that cost a significant percentage of the base board cost are unlikely to be considered.
Power budget 1-2 watts.
It's acceptable for the hardware to have other included functions such as a gpu or sata controller or to exceed the base requirements, but not required. Non essential functions should not be a significant cost factor.
Budget: $50 or less. Not negotiable.
Available ex-stock from farnell/element14 would be very much preferred.
Finally, whatever the SoC, a comprehensive datasheet needs to be publicly available. This datasheet should include all information required to write device drivers for all included hardware.
For anyone who's been following discussions over in the Raspberry Pi area, you may have some insight to the way I've set the requirements. Other devices that have been considered are things like BeagleBone, iMX53-QSB, OlinuXino, Odroid-X, all of which have advantages and disadvantages when measured against the list of requirements.
Thanks for any suggestions you may be able to offer.
