On 29/01/12 22:16, François Revol wrote:
On 29/01/2012 22:48, Miroslav Stimac wrote:After that we need a driver for the GPU Broadcom VideoCore IV.Well you can always spend your time wisely by finding the specs of this chip and linux driver sources and studying them.
There's a simple framebuffer driver under GPL as part of their kernel patch set. https://github.com/raspberrypi/linux/commits/rpi-patches
As far as the hardware accelerated features are concerned - that's not quite as open. AFAIK the kernel-side (and thus GPL) part is just a generic message pipe to the VideoCore - the actual GL/video decode/etc implementations are probably not open. Eben (project lead) is keen to open the GL stack if possible, but that's a call for Broadcom to make, and I don't hold out a lot of hope.
USB would be another hurdle. The USB chip on the board does have a GPL linux driver, and I believe specs might be available there, but I'd imagine a significant porting effort all the same.
Specs for the main SoC aren't really available - Broadcom don't use distributors like TI - they basically only talk to you if you're going to be buying in massive bulk, and then they'll send you some internal engineers to help with all the layout and design issues.
RaspberryPi as a foundation is about computing education, mainly to encourage kids to program. It's never really set out to be an open hardware platform. BeagleBoard is really a better fit for porting efforts, but the price of the RasPi is what makes it so tempting!