RK3399 has a pin that can decide whether GPIO port 1 is driven with 1.8V
or 3.0V. We thought this mechanism was disabled by default, but it turns
out it wasn't. We want to use that pin as an output GPIO on Scarlet so
we need to reconfigure the respective SoC controls before we do that. It
seems that we also need to explicitly pinmux the pin away from that
special function (to normal GPIO) or weird things happen on some boards.
BUG=b:66534913
TEST=Sprinkled several long udelays, poked test points with a
multi-meter on Scarlet.
Change-Id: Ia02cbb4f3b2f14b0d958b84adcddb0c5f4259efa
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/21727
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
e0459c78e4