When splitting a carry chain the original COUT -> carry -> CIN
was preserved. This was not routable if the carry chain is split.
Instead now the COUT is wired to a feed out CC2C whose `S0` port
is the start of the new carry chain.
Each PLL output in ECP5 can be bypassed, which turns it into a wire
that passes through ICLK unmodified. When an outputs mux is set to
REFCLK, disregard other PLL configuration and copy the input constraint
over unchanged.
Currently a segfault happens when the DI port is not specified. Leaving
it unconnected is probably incorrect, but it shouldn't crash the placer.
Fix by adding a check.
This uses a new data structure for net.users that allows gaps, so
removing a port from a net is no longer an O(n) operation on the number
of users the net has.
Signed-off-by: gatecat <gatecat@ds0.me>
Checks that every ALU54B is correctly connected to two MULT18X18Ds:
* SIGNEDIA and SIGNEDIB connected to SIGNEDP
* MA and MB connected to P
* A and B connected to {ROA, ROB}
Diamond enforces these requirements; the connections are fixed
in any event so no other connection is possible.
This replaces the arch-specific DelayInfo structure with new DelayPair
(min/max only) and DelayQuad (min/max for both rise and fall) structures
that form part of common code.
This further reduces the amount of arch-specific code; and also provides
useful data structures for timing analysis which will need to delay
with pairs/quads of delays as it is improved.
While there may be a small performance cost to arches that didn't
separate the rise/fall cases (arches that aren't currently separating
the min/max cases just need to be fixed...) in DelayInfo, my expectation
is that inlining will mean this doesn't make much difference.
Signed-off-by: gatecat <gatecat@ds0.me>
This makes the difference clearer between the general arch API that
everyone must implement; and helper functions specific to one arch.
Signed-off-by: D. Shah <dave@ds0.me>
This uses the new IdStringList API to store bel names for the ECP5. Note
that other arches and the GUI do not yet build with this
proof-of-concept patch.
getBelByName still uses the old implementation and could be more
efficiently implemented with further development.
Signed-off-by: D. Shah <dave@ds0.me>
Rowan Goemans
myrtle
Dave Anderson
laanwj
Miodrag Milanovic
YRabbit
Aidan Klein
Adam Greig
D. Shah