make -C j1a/icestorm Stops with Fatal Error : Failed to place

[RGD2]

with Swapforth@9d45735 built on Ubuntu 14.04.3 LTS, with: cliffordwolf/yosys@5e1dc78 and cseed/arachne-pnr@eb7876b ,

make -C j1a clean
make -C j1a/icestorm

Results in a fatal error to place, apparently because 1297 of 1280 LCs are packed.

I think this an upstream issue with a recent change to yosys, but it's still our issue if we can no longer fit swapforth on a 1k :(

[RGD2]

A problem with yosys? I just found that it builds ok with 1199/1280 LCs on cliffordwolf/yosys@9f5b6e4

... and GOOD NEWS the built image doesn't suffer #15 ! That is, this now works to permanently save developed code into the j1a ROM:

>: test 31 leds ;
>#flash build/nuc.hex
>#bye
make
make -C icestorm/
sudo iceprog icestorm/j1a.bin
sudo python shell.py -h /dev/ttyUSB1
>test

Results in the leds all turning on.

Now, just need to figure out whether cliffordwolf/yosys@5e1dc78 has a regression, or not... I'll open an issue.

[cliffordwolf]

The following change to j1a/icestorm/Makefile will work around the issue (requires todays git head of yosys):

-   yosys  -q -p "synth_ice40 -top top -blif j1a.blif" $(VERILOGS)
+   yosys  -q -p "synth_ice40 -top top -abc2 -blif j1a.blif" $(VERILOGS)

See yosys issue #109 for details.