No functionality change intented.
IHAE "IP Header Alignment Enable" feature of RXC register;
- careful cross referencing at KSZ8692P/8841P/8842P PDFs indicates IHEA
bit works as follows; When the feature is turned on, Rx DMA engine
will populate Rx frame data in the Rx memory with +2 or +3 byte swifted
to make its IP head field 32bit aligned. The shift amount is recorded
inside RDES0 to tell 0, 2 or 3. The automatic alignment is done only
when IHAE is enabled _and_ the Rx frame was IP frame. In other cases,
RDES0 swift amount field keeps 0.
- KSZ8841P document mentions the IHAE bit but its reference link is broken
to tell the new RDES0 field. KSZ8842P lacks both. The bit usage of
RDES0 23:20 seems different from KSZ8692P, which brings me a vague
suspiction of documentation error.
