tREA and tRHOH are parameters of the NAND flash devices, not T4240 ones. On the processor side we recommend to set correct data sampling point: IFC_FTIM2_CSn_NAND[TRAD]. It should be programmed as mention in section 12.5.7.3 of the Ref Manual:
"Read data sampling time (TRAD) represents the read data sampling time on the NAND. The value should be programmed where the sampling at the IFC should be done at the center of the received data eye. Its value can be calculated as [tREAmax (from NAND datasheet) + 2 x board delay + 1/2 received data window size]", where the 'receive data window size' is calculated as tRP - tREA + tRHOH.
Regards,
Bulat
