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| -rw-r--r-- | tests/arch/ice40/ice40_opt.ys | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/tests/arch/ice40/ice40_opt.ys b/tests/arch/ice40/ice40_opt.ys index b17c69c91..58c33acaa 100644 --- a/tests/arch/ice40/ice40_opt.ys +++ b/tests/arch/ice40/ice40_opt.ys @@ -24,3 +24,63 @@ equiv_opt -assert -map +/ice40/cells_map.v -map +/ice40/cells_sim.v ice40_opt design -load postopt select -assert-count 1 t:* select -assert-count 1 t:$lut + +# https://github.com/YosysHQ/yosys/issues/1543 +design -reset +read_verilog <<EOT +module delay_element (input wire clk, input wire reset, input wire enable, + input wire chainin, output wire chainout, output reg latch); + + + reg const_zero = 0; + reg const_one = 1; + + wire delay_tap; + + + //carry logic + (* keep *) SB_CARRY carry ( .CO(chainout), .I0(const_zero), + .I1(const_one), .CI(chainin)); + + + //flip flop latch + (* keep *) SB_DFFER flipflop( .Q(latch), .C(clk), .E(enable), + .D(delay_tap), .R(reset)); + + + //LUT table + // the LUT should just echo the carry in (I3) + // carry I0 = LUT I1 + // carry I1 = LUT I2 + // carry in = LUT I3 + // LUT_INIT[0] = 0 + // LUT_INIT[1] = 0 + // LUT_INIT[2] = 0 + // LUT_INIT[3] = 0 + // LUT_INIT[4] = 0 + // LUT_INIT[5] = 0 + // LUT_INIT[6] = 0 + // LUT_INIT[7] = 0 + // LUT_INIT[8] = 1 + // LUT_INIT[9] = 1 + // LUT_INIT[10] = 1 + // LUT_INIT[11] = 1 + // LUT_INIT[12] = 1 + // LUT_INIT[13] = 1 + // LUT_INIT[14] = 1 + // LUT_INIT[15] = 1 + + (* keep *) SB_LUT4 lut( .O(delay_tap), .I0(const_zero), .I1(const_zero), + .I2(const_one), .I3(chainin)); + + //TODO: is this the right way round?? + defparam lut.LUT_INIT=16'hFF00; + + +endmodule // delay_element +EOT + +synth_ice40 +select -assert-count 1 t:SB_LUT4 +select -assert-count 1 t:SB_CARRY +select -assert-count 1 t:SB_CARRY a:keep %i |