Hi,
MCSPI Slave mode support is not present in StarterWare. However you could try the following -
1) Enable the MCSPI controller in Slave mode by Setting the bit MS of MCSPI_MODULCTRL register.
2) Only channel supported for slave mode is '0'.
3) Configure SPIENSLV bit of MCSPI_CHCONF register to channel '0'
Regards,
Jeethan