This commit:
* renames all remaining instances of "DRAM" (which is ambiguous)
to "LUTRAM" (which is not), finishing the work started in
the commit 698ab9be;
* renames memory rule files to brams.txt/lutrams.txt;
* adds/renames script labels map_bram/map_lutram;
* extracts where necessary script labels map_ffram and map_gates;
* adds where necessary options -nobram/-nolutram.
The end result is that BRAM/LUTRAM/FFRAM aspects of every target
are now consistent with each other.
Per architecture:
* anlogic: rename drams.txt→lutrams.txt, add -nolutram, add
:map_lutram, :map_ffram, :map_gates
* ecp5: rename bram.txt→brams.txt, lutram.txt→lutrams.txt
* efinix: rename bram.txt→brams.txt, add -nobram, add :map_ffram,
:map_gates
* gowin: rename bram.txt→brams.txt, dram.txt→lutrams.txt,
rename -nodram→-nolutram (-nodram still recognized), rename
:bram→:map_bram, :dram→:map_lutram, add :map_ffram, :map_gates
As the TD tool doesn't accept the DRAM cell to contain unknown values in
the initial value, the initialzation support of DRAM is previously
skipped.
Now add the support by add a new pass to determine unknown values in the
initial value.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
