GR2_REVISION_RD0
dc->boardrev = (~(bus_space_read_4(dc->iot, dc->ioh, GR2_REVISION_RD0))) & GR2_REVISION_RD0_VERSION_MASK;
dc->monitor = (bus_space_read_4(dc->iot, dc->ioh, GR2_REVISION_RD0) & GR2_REVISION4_RD0_MONITOR_MASK) >> 4;