TMS570LC4357: Do not write to these register bits - FBPWRMODE

Hi experts,

The register description of the FBPWRMODE-Register mentions that the reserved bits should not be written ("FBPWRMODE").

Does this mean, that when writing to the register the bits should always be 0 and never 1?

For example to set all Banks in Active-Mode, which is correct?

lashWREG->FBPWRMODE = 0x5053FFFF
or
lashWREG->FBPWRMODE = 0x0000C00F

Thank you and best regards,
Max