COM_REG_HALT
CSR_WRITE_1(regsp, COM_REG_HALT, HALT_CHCFG_EN);
CSR_WRITE_1(regsp, COM_REG_HALT,
(CSR_READ_1(regsp, COM_REG_HALT) & HALT_CHCFG_UD) != 0;
CSR_READ_1(regsp, COM_REG_HALT),
CSR_WRITE_1(regsp, COM_REG_HALT, 0);
[COM_REG_HALT] = com_halt,