From 0043ae0807affd77749b162199cd4da3b37d994c Mon Sep 17 00:00:00 2001 From: Ross Schlaikjer Date: Wed, 29 Apr 2020 14:39:52 -0400 Subject: Issue warning for mixed-mode inputs --- ecp5/pack.cc | 47 ++++++++++++++++++++++++++++++++++------------- 1 file changed, 34 insertions(+), 13 deletions(-) (limited to 'ecp5/pack.cc') diff --git a/ecp5/pack.cc b/ecp5/pack.cc index b92a2dfd..1c1df2ee 100644 --- a/ecp5/pack.cc +++ b/ecp5/pack.cc @@ -3052,26 +3052,47 @@ void Arch::assignArchInfo() log_error("MULT18X18D %s has invalid REG_INPUTB_CLK configuration '%s'\n", ci->name.c_str(this), reg_inputb_clk.c_str()); // Inputs are registered IFF the REG_INPUT value is not NONE - ci->multInfo.is_in_a_registered = reg_inputa_clk != "NONE"; - ci->multInfo.is_in_b_registered = reg_inputb_clk != "NONE"; + const bool is_in_a_registered = reg_inputa_clk != "NONE"; + const bool is_in_b_registered = reg_inputb_clk != "NONE"; // Similarly, get the output register clock std::string reg_output_clk = str_or_default(ci->params, id("REG_OUTPUT_CLK"), "NONE"); if (reg_output_clk != "NONE" && reg_output_clk != "CLK0" && reg_output_clk != "CLK1" && reg_output_clk != "CLK2" && reg_output_clk != "CLK3") log_error("MULT18X18D %s has invalid REG_OUTPUT_CLK configuration '%s'\n", ci->name.c_str(this), reg_output_clk.c_str()); - ci->multInfo.is_output_registered = reg_output_clk != "NONE"; - // Based on our register settings, pick the timing data to use for this cell - const bool both_inputs_registered = ci->multInfo.is_in_a_registered && ci->multInfo.is_in_b_registered; - if (!both_inputs_registered && !ci->multInfo.is_output_registered) { - ci->multInfo.timing_id = id_MULT18X18D_REGS_NONE; - } else if (both_inputs_registered && !ci->multInfo.is_output_registered) { - ci->multInfo.timing_id = id_MULT18X18D_REGS_INPUT; - } else if (!both_inputs_registered && ci->multInfo.is_output_registered) { - ci->multInfo.timing_id = id_MULT18X18D_REGS_OUTPUT; - } else if (both_inputs_registered && ci->multInfo.is_output_registered) { - ci->multInfo.timing_id = id_MULT18X18D_REGS_ALL; + const bool is_output_registered = reg_output_clk != "NONE"; + + // If only one of the inputs is registered, we are going to treat that as + // neither input registered so that we don't have to deal with mixed timing. + // Emit a warning to that effect. + const bool any_input_registered = is_in_a_registered || is_in_b_registered; + const bool both_inputs_registered = is_in_a_registered && is_in_b_registered; + const bool input_registers_mismatched = any_input_registered && !both_inputs_registered; + if (input_registers_mismatched) { + log_warning("MULT18X18D %s has unsupported mixed input register modes (reg_inputa_clk=%s, " + "reg_inputb_clk=%s)\n", + ci->name.c_str(this), reg_inputa_clk.c_str(), reg_inputb_clk.c_str()); + log_warning("Timings for MULT18X18D %s will be calculated as though neither input were registered\n", + ci->name.c_str(this)); + + // Act as though the inputs are unregistered, so select timing DB based only on the + // output register mode + ci->multInfo.timing_id = is_output_registered ? id_MULT18X18D_REGS_OUTPUT : id_MULT18X18D_REGS_NONE; + } else { + // Based on our register settings, pick the timing data to use for this cell + if (!both_inputs_registered && !is_output_registered) { + ci->multInfo.timing_id = id_MULT18X18D_REGS_NONE; + } else if (both_inputs_registered && !is_output_registered) { + ci->multInfo.timing_id = id_MULT18X18D_REGS_INPUT; + } else if (!both_inputs_registered && is_output_registered) { + ci->multInfo.timing_id = id_MULT18X18D_REGS_OUTPUT; + } else if (both_inputs_registered && is_output_registered) { + ci->multInfo.timing_id = id_MULT18X18D_REGS_ALL; + } } + // If we aren't a pure combinatorial multiplier, then our timings are + // calculated with respect to CLK0 + ci->multInfo.is_clocked = ci->multInfo.timing_id != id_MULT18X18D_REGS_NONE; } } for (auto net : sorted(nets)) { -- cgit v1.2.3