From: Sylvain Munaut <tnt@246tNt.com>
Date: Sat, 8 Dec 2018 21:46:28 +0000 (+0100)
Subject: ice40: Honor the "dont_touch" attribute in FFSSR pass
X-Git-Tag: yosys-0.9~380^2
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=add6ab9b2a8d94bee0e7949a4524cc673ec336b1;p=yosys.git

ice40: Honor the "dont_touch" attribute in FFSSR pass

This is useful if you want to place FF manually ... can't merge SR in those
because it might make the manual placement invalid

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
---

diff --git a/techlibs/ice40/ice40_ffssr.cc b/techlibs/ice40/ice40_ffssr.cc
index 668df09dd..a7649d7a0 100644
--- a/techlibs/ice40/ice40_ffssr.cc
+++ b/techlibs/ice40/ice40_ffssr.cc
@@ -81,6 +81,9 @@ struct Ice40FfssrPass : public Pass {
 
 			for (auto cell : ff_cells)
 			{
+				if (cell->get_bool_attribute("\\dont_touch"))
+					continue;
+
 				SigSpec sig_d = cell->getPort("\\D");
 
 				if (GetSize(sig_d) < 1)