From 64a5f8f75e99eb9970b69f2d7165c014a57c29cf Mon Sep 17 00:00:00 2001 From: Clifford Wolf Date: Wed, 20 Nov 2013 21:00:43 +0100 Subject: [PATCH] Added "proc_arst -global_arst" feature --- passes/proc/proc.cc | 25 ++++++++++++++-- passes/proc/proc_arst.cc | 64 ++++++++++++++++++++++++++++++++++++---- 2 files changed, 81 insertions(+), 8 deletions(-) diff --git a/passes/proc/proc.cc b/passes/proc/proc.cc index 05f166759..eb99ab005 100644 --- a/passes/proc/proc.cc +++ b/passes/proc/proc.cc @@ -28,7 +28,7 @@ struct ProcPass : public Pass { { // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| log("\n"); - log(" proc [selection]\n"); + log(" proc [options] [selection]\n"); log("\n"); log("This pass calls all the other proc_* passes in the most common order.\n"); log("\n"); @@ -41,17 +41,36 @@ struct ProcPass : public Pass { log("\n"); log("This replaces the processes in the design with multiplexers and flip-flops.\n"); log("\n"); + log("The following options are supported:\n"); + log("\n"); + log(" -global_arst [!]\n"); + log(" This option is passed through to proc_arst.\n"); + log("\n"); } virtual void execute(std::vector args, RTLIL::Design *design) { + std::string global_arst; + log_header("Executing PROC pass (convert processes to netlists).\n"); log_push(); - extra_args(args, 1, design); + size_t argidx; + for (argidx = 1; argidx < args.size(); argidx++) + { + if (args[argidx] == "-global_arst" && argidx+1 < args.size()) { + global_arst = args[++argidx]; + continue; + } + break; + } + extra_args(args, argidx, design); Pass::call(design, "proc_clean"); Pass::call(design, "proc_rmdead"); - Pass::call(design, "proc_arst"); + if (global_arst.empty()) + Pass::call(design, "proc_arst"); + else + Pass::call(design, "proc_arst -global_arst " + global_arst); Pass::call(design, "proc_mux"); Pass::call(design, "proc_dff"); Pass::call(design, "proc_clean"); diff --git a/passes/proc/proc_arst.cc b/passes/proc/proc_arst.cc index 021d87c81..65dc97bdd 100644 --- a/passes/proc/proc_arst.cc +++ b/passes/proc/proc_arst.cc @@ -196,25 +196,79 @@ struct ProcArstPass : public Pass { { // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| log("\n"); - log(" proc_arst [selection]\n"); + log(" proc_arst [-global_arst [!]] [selection]\n"); log("\n"); log("This pass identifies asynchronous resets in the processes and converts them\n"); log("to a different internal representation that is suitable for generating\n"); log("flip-flop cells with asynchronous resets.\n"); log("\n"); + log(" -global_arst [!]\n"); + log(" In modules that have a net with the given name, use this net as async\n"); + log(" reset for registers that have been assign initial values in their\n"); + log(" declaration ('reg foobar = constant_value;'). Use the '!' modifier for\n"); + log(" active low reset signals. Note: the frontend stores the default value\n"); + log(" in the 'init' attribute on the net.\n"); + log("\n"); } virtual void execute(std::vector args, RTLIL::Design *design) { + std::string global_arst; + bool global_arst_neg = false; + log_header("Executing PROC_ARST pass (detect async resets in processes).\n"); - extra_args(args, 1, design); + size_t argidx; + for (argidx = 1; argidx < args.size(); argidx++) + { + if (args[argidx] == "-global_arst" && argidx+1 < args.size()) { + global_arst = args[++argidx]; + if (!global_arst.empty() && global_arst[0] == '!') { + global_arst_neg = true; + global_arst = global_arst.substr(1); + } + global_arst = RTLIL::escape_id(global_arst); + continue; + } + break; + } + + extra_args(args, argidx, design); for (auto &mod_it : design->modules) if (design->selected(mod_it.second)) { SigMap assign_map(mod_it.second); - for (auto &proc_it : mod_it.second->processes) - if (design->selected(mod_it.second, proc_it.second)) - proc_arst(mod_it.second, proc_it.second, assign_map); + for (auto &proc_it : mod_it.second->processes) { + if (!design->selected(mod_it.second, proc_it.second)) + continue; + proc_arst(mod_it.second, proc_it.second, assign_map); + if (global_arst.empty() || mod_it.second->wires.count(global_arst) == 0) + continue; + std::vector arst_actions; + for (auto sync : proc_it.second->syncs) + if (sync->type == RTLIL::SyncType::STp || sync->type == RTLIL::SyncType::STn) + for (auto &act : sync->actions) { + RTLIL::SigSpec arst_sig, arst_val; + for (auto &chunk : act.first.chunks) + if (chunk.wire && chunk.wire->attributes.count("\\init")) { + RTLIL::SigSpec value = chunk.wire->attributes.at("\\init"); + value.extend(chunk.wire->width, false); + arst_sig.append(chunk); + arst_val.append(value.extract(chunk.offset, chunk.width)); + } + if (arst_sig.width) { + log("Added global reset to process %s: %s <- %s\n", + proc_it.first.c_str(), log_signal(arst_sig), log_signal(arst_val)); + arst_actions.push_back(RTLIL::SigSig(arst_sig, arst_val)); + } + } + if (!arst_actions.empty()) { + RTLIL::SyncRule *sync = new RTLIL::SyncRule; + sync->type = global_arst_neg ? RTLIL::SyncType::ST0 : RTLIL::SyncType::ST1; + sync->signal = mod_it.second->wires.at(global_arst); + sync->actions = arst_actions; + proc_it.second->syncs.push_back(sync); + } + } } } } ProcArstPass; -- 2.30.2