CHIPC_SYS_CLK_CTL
div = bhnd_bus_read_4(sc->res, CHIPC_SYS_CLK_CTL);
bhnd_bus_write_4(sc->res, CHIPC_SYS_CLK_CTL, clkctl);
scc = bhnd_bus_read_4(sc->res, CHIPC_SYS_CLK_CTL);
bhnd_bus_write_4(sc->res, CHIPC_SYS_CLK_CTL, scc);
bhnd_bus_write_4(sc->res, CHIPC_SYS_CLK_CTL, scc);