Commit Graph

4 Commits

Author SHA1 Message Date
Sean Anderson a75b77d8e5 Add OHL license option
The AGPL was mostly a placeholder until I determined a better license to
use. TBH I wasn't expecting that anyone would find this repo.

Closes: #1
Signed-off-by: Sean Anderson <seanga2@gmail.com>
2023-03-17 20:38:08 -04:00
Sean Anderson 3b9efe2211 mii_elastic_buffer: Don't use memory access hack on valid/err
We can already probe the valid/err signals, so we don't need to
explicitly access them.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
2023-02-18 22:48:36 -05:00
Sean Anderson eb8d854476 Silence warnings when converting memories to registers
There are several places where memories are used for parametrization
purposes, but I intend them to be synthesized to registers. Silence
warnings about them by explicitly annotating these variables.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
2023-02-18 22:48:36 -05:00
Sean Anderson 16b639aad2 Add MII elastic buffer
In order to move data between MIIs without implementing a MAC, we need
some kind of elastic buffer to bring the data into the transmit "clock
(enable) domain." Implement one. It's based on a classic shift-register
FIFO, with the main difference being the MII interfaces and the
elasticity (achieved by delaying asserting RX_DV until we reach the
WATERMARK). We use a register-based buffer because we only need to deal
with an under-/over-flow of 5 or so clocks for a 2000-byte packet. The
per-stage resource increase works out to 6 FFs and 1 LUT, which is
pretty much optimal.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
2023-02-12 19:53:44 -05:00