o Implemented miibus_statchg handler. It detects whether re(4)
established a valid link or not. In miibus_statchg handler add a check for established link is valid one for the controller(e.g. 1000baseT is not a valid link for fastethernet controllers.)
o Added a flag RE_FLAG_FASTETHER to mark fastethernet controllers.
o Added additional check to know whether we've really encountered
watchdog timeouts or missed Tx completion interrupts. This change may help to track down the cause of watchdog timeouts.
o In interrupt handler, removed a check for link state change
interrupt. Not all controllers have the bit and re(4) did not rely on the event for a long time. In addition, re(4) didn't request the interrupt in RL_IMR register.
Tested by: rpaulo