Rather than completely rewriting everything on each runthrough, we
now only refill the command buffer before toggling the RUN bit.
This will improve performance by eliminating excessive register writes.
Signed-off-by: Sean Cross <xobs@kosagi.com>
This supports setting up the LCD, and then starting a transfer.
Interrupts are required to have self-refresh working.
Signed-off-by: Sean Cross <xobs@kosagi.com>
