I have Linux running on an at91sam9g20-ek rev B board. Where can I get a (preferrably free) compiler, either to install on Linux on this board, or install on another machine (either Linux on PC or Windows) that can build and then I can transfer to this board?

I tried to answer this when it was posted, but the ATMEL forum threw it's classic SQL attack warning and ate the post.

You can use GCC targeted for ARM, buildroot creates it in the output directory as part of it's build process.

* output * host * usr * bin * arm-linux-gcc

Using '*' as a directory separator to avoid the post being eaten.

This can be used to build ARM applications, and things like uBoot.

On a Windows PC, one could use WinARM or Yagarto, to build things like AT91BootStrap. On the commercial side, AT91BootStrap can also be built and debugged with Keil.

Thanks. Things are clearing up. I saw also a product called Sourcery Lite. Free download, has the arm-none-linux-gnueabi-gcc compiler with it, etc. Seems to work well on both Linux and Windows, in case anyone in the future has this same question.