MC_REGB
mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
mc146818_write(sc, MC_REGB,
mc146818_write(NULL, MC_REGB, MC_REGB_24HR | MC_REGB_PIE);
mc146818_write(NULL, MC_REGB, MC_REGB_24HR);
mc146818_write(NULL, MC_REGB, MC_REGB_24HR | MC_REGB_AIE);
mc146818_write(NULL, MC_REGB, MC_REGB_24HR);
if ((mc146818_read(NULL, MC_REGB) & MC_REGB_AIE) == 0)
mc146818_write(NULL, MC_REGB, MC_REGB_24HR | MC_REGB_PIE);
mc146818_write(NULL, MC_REGB, MC_REGB_24HR);
mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
rtc_write_reg(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR);
csr = rtc_read_reg(sc, MC_REGB);
rtc_write_reg(sc, MC_REGB, csr);
csr = rtc_read_reg(sc, MC_REGB);
rtc_write_reg(sc, MC_REGB, csr);
csr = rtc_read_reg(sc, MC_REGB);
rtc_write_reg(sc, MC_REGB, csr);
csr = rtc_read_reg(sc, MC_REGB);
rtc_write_reg(sc, MC_REGB, csr);
mc146818_write(sc, MC_REGB, \
mc146818_read(sc, MC_REGB) | MC_REGB_SET); \
mc146818_write(sc, MC_REGB, \
mc146818_read(sc, MC_REGB) & ~MC_REGB_SET); \
rtc.regs[MC_REGB] = MC_REGB_24HR;
if (rtc.regs[MC_REGB] & MC_REGB_PIE) {
rtc.regs[MC_REGB] = data;
case MC_REGB: