Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32n6/STM32N645/ETH/ETH_DMAC0RXIWTR#0x0
RWTU=B_0x0
Channel 0 R0 interrupt watchdog timer register
Receive Interrupt Watchdog Timer Count
Receive Interrupt Watchdog Timer Count Units
0 (B_0x0): 256
1 (B_0x1): 512
2 (B_0x2): 1024
3 (B_0x3): 2048
https://github.com/modm-io/cmsis-svd-stm32