I need to build a common kernel (so that SD cards are exchangeable)
and I found that some GPIOs connected to expansion headers have been
moved between BB-C4 and BB-XM (especially the DSS lines where I use 6
of them as additional GPIOs since the display has only 18 bit). So my
kernel setup code and drivers needs to access different GPIOs
depending on which board they run.
Having two different SD card images or configuring different bootargs
is not a solution.
So what is the easiest way to determine the BB version in the kernel?
Should I port the GPIO171-173 detection logic from U-Boot? Or should I
try to detect the CPU version (OMAP3530 vs. DM3730)? My kernel is
based on http://gitorious.org/beagleboard-validation/linux/commits/beagleboardXM