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Diffstat (limited to 'passes/memory/memory_nordff.cc')
| -rw-r--r-- | passes/memory/memory_nordff.cc | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/passes/memory/memory_nordff.cc b/passes/memory/memory_nordff.cc new file mode 100644 index 00000000..ba0361c0 --- /dev/null +++ b/passes/memory/memory_nordff.cc @@ -0,0 +1,121 @@ +/* + * yosys -- Yosys Open SYnthesis Suite + * + * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + */ + +#include "kernel/yosys.h" +#include "kernel/sigtools.h" + +USING_YOSYS_NAMESPACE +PRIVATE_NAMESPACE_BEGIN + +struct MemoryNordffPass : public Pass { + MemoryNordffPass() : Pass("memory_nordff", "extract read port FFs from memories") { } + void help() YS_OVERRIDE + { + // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| + log("\n"); + log(" memory_nordff [options] [selection]\n"); + log("\n"); + log("This pass extracts FFs from memory read ports. This results in a netlist\n"); + log("similar to what one would get from calling memory_dff with -nordff.\n"); + log("\n"); + } + void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE + { + log_header(design, "Executing MEMORY_NORDFF pass (extracting $dff cells from $mem).\n"); + + size_t argidx; + for (argidx = 1; argidx < args.size(); argidx++) { + // if (args[argidx] == "-nordff" || args[argidx] == "-wr_only") { + // flag_wr_only = true; + // continue; + // } + break; + } + extra_args(args, argidx, design); + + for (auto module : design->selected_modules()) + for (auto cell : vector<Cell*>(module->selected_cells())) + { + if (cell->type != "$mem") + continue; + + int rd_ports = cell->getParam("\\RD_PORTS").as_int(); + int abits = cell->getParam("\\ABITS").as_int(); + int width = cell->getParam("\\WIDTH").as_int(); + + SigSpec rd_addr = cell->getPort("\\RD_ADDR"); + SigSpec rd_data = cell->getPort("\\RD_DATA"); + SigSpec rd_clk = cell->getPort("\\RD_CLK"); + SigSpec rd_en = cell->getPort("\\RD_EN"); + Const rd_clk_enable = cell->getParam("\\RD_CLK_ENABLE"); + Const rd_clk_polarity = cell->getParam("\\RD_CLK_POLARITY"); + + for (int i = 0; i < rd_ports; i++) + { + bool clk_enable = rd_clk_enable[i] == State::S1; + + if (clk_enable) + { + bool clk_polarity = cell->getParam("\\RD_CLK_POLARITY")[i] == State::S1; + bool transparent = cell->getParam("\\RD_TRANSPARENT")[i] == State::S1; + + SigSpec clk = cell->getPort("\\RD_CLK")[i] ; + SigSpec en = cell->getPort("\\RD_EN")[i]; + Cell *c; + + if (transparent) + { + SigSpec sig_q = module->addWire(NEW_ID, abits); + SigSpec sig_d = rd_addr.extract(abits * i, abits); + rd_addr.replace(abits * i, sig_q); + if (en != State::S1) + sig_d = module->Mux(NEW_ID, sig_q, sig_d, en); + c = module->addDff(NEW_ID, clk, sig_d, sig_q, clk_polarity); + } + else + { + SigSpec sig_d = module->addWire(NEW_ID, width); + SigSpec sig_q = rd_data.extract(width * i, width); + rd_data.replace(width *i, sig_d); + if (en != State::S1) + sig_d = module->Mux(NEW_ID, sig_q, sig_d, en); + c = module->addDff(NEW_ID, clk, sig_d, sig_q, clk_polarity); + } + + log("Extracted %s FF from read port %d of %s.%s: %s\n", transparent ? "addr" : "data", + i, log_id(module), log_id(cell), log_id(c)); + } + + rd_en[i] = State::S1; + rd_clk[i] = State::S0; + rd_clk_enable[i] = State::S0; + rd_clk_polarity[i] = State::S1; + } + + cell->setPort("\\RD_ADDR", rd_addr); + cell->setPort("\\RD_DATA", rd_data); + cell->setPort("\\RD_CLK", rd_clk); + cell->setPort("\\RD_EN", rd_en); + cell->setParam("\\RD_CLK_ENABLE", rd_clk_enable); + cell->setParam("\\RD_CLK_POLARITY", rd_clk_polarity); + } + } +} MemoryNordffPass; + +PRIVATE_NAMESPACE_END |