SUN2_CLK_NMI
am9513_write_clk_cmd(AM9513_CMD_DISARM(SUN2_CLK_TIMER | SUN2_CLK_NMI));
am9513_write_clk_cmd(AM9513_CMD_CLEAR_OUTPUT(SUN2_CLK_NMI));
timer = (prom_clock ? SUN2_CLK_NMI : SUN2_CLK_TIMER);