From b1787615514f84c83c27d08011427e90c9bd0f4a Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Fri, 24 Jan 2020 11:59:48 -0800 Subject: [PATCH] ice40: reduce ABC9 internal fanout warnings with a param for CI->I3 --- passes/pmgen/ice40_wrapcarry.cc | 15 ++++++++++++--- techlibs/ice40/abc9_model.v | 4 +++- techlibs/ice40/abc9_u.box | 3 +-- techlibs/ice40/arith_map.v | 5 +++-- techlibs/ice40/ice40_opt.cc | 4 +++- tests/arch/ice40/ice40_opt.ys | 27 ++++----------------------- 6 files changed, 26 insertions(+), 32 deletions(-) diff --git a/passes/pmgen/ice40_wrapcarry.cc b/passes/pmgen/ice40_wrapcarry.cc index 6e154147f..d458dce46 100644 --- a/passes/pmgen/ice40_wrapcarry.cc +++ b/passes/pmgen/ice40_wrapcarry.cc @@ -42,11 +42,19 @@ void create_ice40_wrapcarry(ice40_wrapcarry_pm &pm) cell->setPort("\\A", st.carry->getPort("\\I0")); cell->setPort("\\B", st.carry->getPort("\\I1")); - cell->setPort("\\CI", st.carry->getPort("\\CI")); + auto CI = st.carry->getPort("\\CI"); + cell->setPort("\\CI", CI); cell->setPort("\\CO", st.carry->getPort("\\CO")); cell->setPort("\\I0", st.lut->getPort("\\I0")); - cell->setPort("\\I3", st.lut->getPort("\\I3")); + auto I3 = st.lut->getPort("\\I3"); + if (pm.sigmap(CI) == pm.sigmap(I3)) { + cell->setParam("\\I3_IS_CI", State::S1); + I3 = State::Sx; + } + else + cell->setParam("\\I3_IS_CI", State::S0); + cell->setPort("\\I3", I3); cell->setPort("\\O", st.lut->getPort("\\O")); cell->setParam("\\LUT", st.lut->getParam("\\LUT_INIT")); @@ -118,7 +126,8 @@ struct Ice40WrapCarryPass : public Pass { auto lut = module->addCell(lut_name, ID($lut)); lut->setParam(ID(WIDTH), 4); lut->setParam(ID(LUT), cell->getParam(ID(LUT))); - lut->setPort(ID(A), {cell->getPort(ID(I0)), cell->getPort(ID(A)), cell->getPort(ID(B)), cell->getPort(ID(I3)) }); + auto I3 = cell->getPort(cell->getParam(ID(I3_IS_CI)).as_bool() ? ID(CI) : ID(I3)); + lut->setPort(ID(A), {cell->getPort(ID(I0)), cell->getPort(ID(A)), cell->getPort(ID(B)), I3 }); lut->setPort(ID(Y), cell->getPort(ID(O))); Const src; diff --git a/techlibs/ice40/abc9_model.v b/techlibs/ice40/abc9_model.v index 26cf6cc22..a5e5f4372 100644 --- a/techlibs/ice40/abc9_model.v +++ b/techlibs/ice40/abc9_model.v @@ -9,6 +9,8 @@ module \$__ICE40_CARRY_WRAPPER ( input I0, I3 ); parameter LUT = 0; + parameter I3_IS_CI = 0; + wire I3_OR_CI = I3_IS_CI ? CI : I3; SB_CARRY carry ( .I0(A), .I1(B), @@ -21,7 +23,7 @@ module \$__ICE40_CARRY_WRAPPER ( .I0(I0), .I1(A), .I2(B), - .I3(I3), + .I3(I3_OR_CI), .O(O) ); endmodule diff --git a/techlibs/ice40/abc9_u.box b/techlibs/ice40/abc9_u.box index 48a51463e..3d4b93834 100644 --- a/techlibs/ice40/abc9_u.box +++ b/techlibs/ice40/abc9_u.box @@ -6,13 +6,12 @@ # Box 1 : $__ICE40_CARRY_WRAPPER (private cell used to preserve # SB_LUT4+SB_CARRY) -# Outputs: O, CO # (Exception: carry chain input/output must be the # last input and output and the entire bus has been # moved there overriding the otherwise # alphabetical ordering) # name ID w/b ins outs $__ICE40_CARRY_WRAPPER 1 1 5 2 -#A B I0 I3 CI +#A B I0 I3 CI 1231 1205 1285 874 874 # O 675 609 - - 278 # CO diff --git a/techlibs/ice40/arith_map.v b/techlibs/ice40/arith_map.v index 00a07247b..ed4140e44 100644 --- a/techlibs/ice40/arith_map.v +++ b/techlibs/ice40/arith_map.v @@ -49,13 +49,14 @@ module _80_ice40_alu (A, B, CI, BI, X, Y, CO); // A[1]: 1100 1100 1100 1100 // A[2]: 1111 0000 1111 0000 // A[3]: 1111 1111 0000 0000 - .LUT(16'b 0110_1001_1001_0110) + .LUT(16'b 0110_1001_1001_0110), + .I3_IS_CI(1'b1) ) carry ( .A(AA[i]), .B(BB[i]), .CI(C[i]), .I0(1'b0), - .I3(C[i]), + .I3(1'bx), .CO(CO[i]), .O(Y[i]) ); diff --git a/techlibs/ice40/ice40_opt.cc b/techlibs/ice40/ice40_opt.cc index 9bee0444b..df10a2842 100644 --- a/techlibs/ice40/ice40_opt.cc +++ b/techlibs/ice40/ice40_opt.cc @@ -139,7 +139,8 @@ static void run_ice40_opts(Module *module) log("Optimized $__ICE40_CARRY_WRAPPER cell back to logic (without SB_CARRY) %s.%s: CO=%s\n", log_id(module), log_id(cell), log_signal(replacement_output)); cell->type = "$lut"; - cell->setPort("\\A", { cell->getPort("\\I0"), inbit[0], inbit[1], cell->getPort("\\I3") }); + auto I3 = cell->getPort(cell->getParam(ID(I3_IS_CI)).as_bool() ? ID(CI) : ID(I3)); + cell->setPort("\\A", { cell->getPort("\\I0"), inbit[0], inbit[1], I3 }); cell->setPort("\\Y", cell->getPort("\\O")); cell->unsetPort("\\B"); cell->unsetPort("\\CI"); @@ -148,6 +149,7 @@ static void run_ice40_opts(Module *module) cell->unsetPort("\\CO"); cell->unsetPort("\\O"); cell->setParam("\\WIDTH", 4); + cell->unsetParam("\\I3_IS_CI"); } continue; } diff --git a/tests/arch/ice40/ice40_opt.ys b/tests/arch/ice40/ice40_opt.ys index 5186d4800..011d98fef 100644 --- a/tests/arch/ice40/ice40_opt.ys +++ b/tests/arch/ice40/ice40_opt.ys @@ -1,23 +1,3 @@ -read_verilog -icells -formal <