SIBA_CFG0_IDLOW
idl = bhnd_bus_read_4(r, SIBA_CFG0_IDLOW);
idlow = siba_eio_read_4(io, core_idx, SB0_REG_ABS(SIBA_CFG0_IDLOW));
SB0_REG_ABS(SIBA_CFG0_IDLOW));