The counters in this module end up on the critical path a lot. The
counters themselves take 3-4 ns to compute, but routing the increment
signal to the counter eats up a lot of slack. Register the increment signal
for a clock to let it cross the FPGA without affecting the counter timing.
Signed-off-by: Sean Anderson <seanga2@gmail.com>
ack/err can only be combinatorial if data_read is also combinatorial.
I suspect doing that will kill my Fmax, so register ack/err.
Fixes: d9602b6 ("Add MII management functions")
Signed-off-by: Sean Anderson <seanga2@gmail.com>
This adds an explicit false carrier signal. Trying to determine this
condition the MDIO signals is tricky because BAD_SSD can last over
several cycles of CE. To make things easier, add a signal which is high
only once per event.
Signed-off-by: Sean Anderson <seanga2@gmail.com>
This adds support for counters for interesting conditions (disconnects,
PMD phase wraparounds, errors, etc). All the counters are 15 bits
instead of 16, because 16-bit counters have an fmax of 110MHz or so. All
the counters live behind a condition because they ~double the number of
resources used.
Signed-off-by: Sean Anderson <seanga2@gmail.com>
This adds a module implementing the the MII management functions (the
MDIO regs). For the moment, we just implement the standard registers.
Signed-off-by: Sean Anderson <seanga2@gmail.com>