Q. When booting from it everything should be initialized by the Bootloder, correct? All the things which are done in ‘FLEXSPI_Init’ shouldn’t be necessary, only the LUT should be initialized, right?
A. Seems that only the Read path of the FlexSPI controller is initialized by the BootROM code to XiP the code from HyperFlash. So, the right sequence seems to move the code that initializes the FlexSPI Write path and then performs read/erase/write to ITCM, then jump there, initialize the Write path first and then perform read/erase/write only from ITCM as a separate and complete routine.