From 8f0e796be131c2a47694e786ff901cc9970917c6 Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Fri, 19 Jul 2019 10:38:13 -0700 Subject: [PATCH] Add support for ice40 signed multipliers --- passes/pmgen/ice40_dsp.cc | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/passes/pmgen/ice40_dsp.cc b/passes/pmgen/ice40_dsp.cc index 39d033a04..963a7d7a1 100644 --- a/passes/pmgen/ice40_dsp.cc +++ b/passes/pmgen/ice40_dsp.cc @@ -62,32 +62,27 @@ void create_ice40_dsp(ice40_dsp_pm &pm) return; } - bool mul_signed = st.mul->getParam("\\A_SIGNED").as_bool(); - - if (mul_signed) { - log(" inference of signed iCE40 DSP arithmetic is currently not supported.\n"); - return; - } - - log(" replacing $mul with SB_MAC16 cell.\n"); + log(" replacing %s with SB_MAC16 cell.\n", log_id(st.mul->type)); Cell *cell = pm.module->addCell(NEW_ID, "\\SB_MAC16"); pm.module->swap_names(cell, st.mul); // SB_MAC16 Input Interface + bool a_signed = st.mul->getParam("\\A_SIGNED").as_bool(); + bool b_signed = st.mul->getParam("\\B_SIGNED").as_bool(); SigSpec A = st.sigA; - A.extend_u0(16, mul_signed); + A.extend_u0(16, a_signed); SigSpec B = st.sigB; - B.extend_u0(16, mul_signed); + B.extend_u0(16, b_signed); SigSpec CD; if (st.muxA) CD = st.muxA->getPort("\\B"); if (st.muxB) CD = st.muxB->getPort("\\A"); - CD.extend_u0(32, mul_signed); + CD.extend_u0(32, a_signed && b_signed); cell->setPort("\\A", A); cell->setPort("\\B", B); @@ -198,8 +193,8 @@ void create_ice40_dsp(ice40_dsp_pm &pm) cell->setParam("\\BOTADDSUB_CARRYSELECT", Const(0, 2)); cell->setParam("\\MODE_8x8", State::S0); - cell->setParam("\\A_SIGNED", mul_signed ? State::S1 : State::S0); - cell->setParam("\\B_SIGNED", mul_signed ? State::S1 : State::S0); + cell->setParam("\\A_SIGNED", a_signed); + cell->setParam("\\B_SIGNED", b_signed); pm.autoremove(st.mul); pm.autoremove(st.ffY); -- 2.30.2