qSPI can work with non-flash device as long as it meets the timing spec. You can have up to 16 LUT sequences to deal with different slaves, which is not necessary flash devices.
qSPI does not support Mode 1 operation as it drives data on falling edge and samples data on rising edge.
qSPI does not support slave mode.
Refer to the QorIQ LS1046A Reference Manual, 27.6.3.5 Issuing SFM Commands and the following presentation:
https://www.nxp.com/webapp/Download?colCode=FTF-NET-F0008&location=null