On Wed, Jul 09, 2014 at 12:31:47PM +0200, Lucas Stach wrote:

quoted

You could also take the easy way out and enable all power domains by
default. So drivers won't be able to disable the power domain on old
DTBs where they aren't hooked up, but the will continue to function
without calling into the old Tegra specific power domain code.

If the bootloader turned some domains off, the kernel would have to turn them
back on again. However that requires knowledge about the clocks and resets of
the peripherals in the domain.

Cheers,

Peter.