yosys/techlibs/coolrunner2/coolrunner2_sop.cc

315 lines
11 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2017 Robert Ou <rqou@robertou.com>
*
* 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 Coolrunner2SopPass : public Pass {
Coolrunner2SopPass() : Pass("coolrunner2_sop", "break $sop cells into ANDTERM/ORTERM cells") { }
void help() YS_OVERRIDE
{
log("\n");
log(" coolrunner2_sop [options] [selection]\n");
log("\n");
log("Break $sop cells into ANDTERM/ORTERM cells.\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
{
log_header(design, "Executing COOLRUNNER2_SOP pass (break $sop cells into ANDTERM/ORTERM cells).\n");
extra_args(args, 1, design);
for (auto module : design->selected_modules())
{
pool<Cell*> cells_to_remove;
SigMap sigmap(module);
// Find all the $_NOT_ cells
dict<SigBit, tuple<SigBit, Cell*>> not_cells;
for (auto cell : module->selected_cells())
{
if (cell->type == "$_NOT_")
{
auto not_input = sigmap(cell->getPort("\\A")[0]);
auto not_output = sigmap(cell->getPort("\\Y")[0]);
not_cells[not_input] = tuple<SigBit, Cell*>(not_output, cell);
}
}
// Find wires that need to become special product terms
dict<SigBit, pool<tuple<Cell*, std::string>>> special_pterms_no_inv;
dict<SigBit, pool<tuple<Cell*, std::string>>> special_pterms_inv;
for (auto cell : module->selected_cells())
{
if (cell->type.in("\\FDCP", "\\FDCP_N", "\\FDDCP", "\\FTCP", "\\FTCP_N", "\\FTDCP",
"\\FDCPE", "\\FDCPE_N", "\\FDDCPE", "\\LDCP", "\\LDCP_N"))
{
if (cell->hasPort("\\PRE"))
special_pterms_no_inv[sigmap(cell->getPort("\\PRE")[0])].insert(
tuple<Cell*, const char *>(cell, "\\PRE"));
if (cell->hasPort("\\CLR"))
special_pterms_no_inv[sigmap(cell->getPort("\\CLR")[0])].insert(
tuple<Cell*, const char *>(cell, "\\CLR"));
if (cell->hasPort("\\CE"))
special_pterms_no_inv[sigmap(cell->getPort("\\CE")[0])].insert(
tuple<Cell*, const char *>(cell, "\\CE"));
if (cell->hasPort("\\C"))
special_pterms_inv[sigmap(cell->getPort("\\C")[0])].insert(
tuple<Cell*, const char *>(cell, "\\C"));
if (cell->hasPort("\\G"))
special_pterms_inv[sigmap(cell->getPort("\\G")[0])].insert(
tuple<Cell*, const char *>(cell, "\\G"));
}
}
// Process $sop cells
for (auto cell : module->selected_cells())
{
if (cell->type == "$sop")
{
// Read the inputs/outputs/parameters of the $sop cell
auto sop_inputs = sigmap(cell->getPort("\\A"));
auto sop_output = sigmap(cell->getPort("\\Y"))[0];
auto sop_depth = cell->getParam("\\DEPTH").as_int();
auto sop_width = cell->getParam("\\WIDTH").as_int();
auto sop_table = cell->getParam("\\TABLE");
// Check for a $_NOT_ at the output
bool has_invert = false;
if (not_cells.count(sop_output))
{
auto not_cell = not_cells.at(sop_output);
has_invert = true;
sop_output = std::get<0>(not_cell);
// remove the $_NOT_ cell because it gets folded into the xor
cells_to_remove.insert(std::get<1>(not_cell));
}
// Check for special P-term usage
bool is_special_pterm = false;
bool special_pterm_can_invert = false;
if (special_pterms_no_inv.count(sop_output) || special_pterms_inv.count(sop_output))
{
is_special_pterm = true;
if (!special_pterms_no_inv[sop_output].size())
special_pterm_can_invert = true;
}
// Construct AND cells
pool<SigBit> intermed_wires;
for (int i = 0; i < sop_depth; i++) {
// Wire for the output
auto and_out = module->addWire(NEW_ID);
intermed_wires.insert(and_out);
// Signals for the inputs
pool<SigBit> and_in_true;
pool<SigBit> and_in_comp;
for (int j = 0; j < sop_width; j++)
{
if (sop_table[2 * (i * sop_width + j) + 0])
{
and_in_comp.insert(sop_inputs[j]);
}
if (sop_table[2 * (i * sop_width + j) + 1])
{
and_in_true.insert(sop_inputs[j]);
}
}
// Construct the cell
auto and_cell = module->addCell(NEW_ID, "\\ANDTERM");
and_cell->setParam("\\TRUE_INP", GetSize(and_in_true));
and_cell->setParam("\\COMP_INP", GetSize(and_in_comp));
and_cell->setPort("\\OUT", and_out);
and_cell->setPort("\\IN", and_in_true);
and_cell->setPort("\\IN_B", and_in_comp);
}
if (sop_depth == 1)
{
// If there is only one term, don't construct an OR cell. Directly construct the XOR gate
auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR");
xor_cell->setParam("\\INVERT_OUT", has_invert);
xor_cell->setPort("\\IN_PTC", *intermed_wires.begin());
xor_cell->setPort("\\OUT", sop_output);
// Special P-term handling
if (is_special_pterm)
{
if (!has_invert || special_pterm_can_invert)
{
// Can connect the P-term directly to the special term sinks
for (auto x : special_pterms_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), *intermed_wires.begin());
for (auto x : special_pterms_no_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), *intermed_wires.begin());
}
if (has_invert)
{
if (special_pterm_can_invert)
{
log_assert(special_pterms_no_inv[sop_output].size() == 0);
for (auto x : special_pterms_inv[sop_output])
{
auto cell = std::get<0>(x);
// Need to invert the polarity of the cell
if (cell->type == "\\FDCP") cell->type = "\\FDCP_N";
else if (cell->type == "\\FDCP_N") cell->type = "\\FDCP";
else if (cell->type == "\\FTCP") cell->type = "\\FTCP_N";
else if (cell->type == "\\FTCP_N") cell->type = "\\FTCP";
else if (cell->type == "\\FDCPE") cell->type = "\\FDCPE_N";
else if (cell->type == "\\FDCPE_N") cell->type = "\\FDCPE";
else if (cell->type == "\\LDCP") cell->type = "\\LDCP_N";
else if (cell->type == "\\LDCP_N") cell->type = "\\LDCP";
else log_assert(!"Internal error! Bad cell type!");
}
}
else
{
// Need to construct a feed-through term
auto feedthrough_out = module->addWire(NEW_ID);
auto feedthrough_cell = module->addCell(NEW_ID, "\\ANDTERM");
feedthrough_cell->setParam("\\TRUE_INP", 1);
feedthrough_cell->setParam("\\COMP_INP", 0);
feedthrough_cell->setPort("\\OUT", feedthrough_out);
feedthrough_cell->setPort("\\IN", sop_output);
feedthrough_cell->setPort("\\IN_B", SigSpec());
for (auto x : special_pterms_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), feedthrough_out);
for (auto x : special_pterms_no_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), feedthrough_out);
}
}
}
}
else
{
// Wire from OR to XOR
auto or_to_xor_wire = module->addWire(NEW_ID);
// Construct the OR cell
auto or_cell = module->addCell(NEW_ID, "\\ORTERM");
or_cell->setParam("\\WIDTH", sop_depth);
or_cell->setPort("\\IN", intermed_wires);
or_cell->setPort("\\OUT", or_to_xor_wire);
// Construct the XOR cell
auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR");
xor_cell->setParam("\\INVERT_OUT", has_invert);
xor_cell->setPort("\\IN_ORTERM", or_to_xor_wire);
xor_cell->setPort("\\OUT", sop_output);
if (is_special_pterm)
{
// Need to construct a feed-through term
auto feedthrough_out = module->addWire(NEW_ID);
auto feedthrough_cell = module->addCell(NEW_ID, "\\ANDTERM");
feedthrough_cell->setParam("\\TRUE_INP", 1);
feedthrough_cell->setParam("\\COMP_INP", 0);
feedthrough_cell->setPort("\\OUT", feedthrough_out);
feedthrough_cell->setPort("\\IN", sop_output);
feedthrough_cell->setPort("\\IN_B", SigSpec());
for (auto x : special_pterms_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), feedthrough_out);
for (auto x : special_pterms_no_inv[sop_output])
std::get<0>(x)->setPort(std::get<1>(x), feedthrough_out);
}
}
// Finally, remove the $sop cell
cells_to_remove.insert(cell);
}
}
// In some cases we can get a FF feeding straight into an FF. This is not possible, so we need to insert
// some AND/XOR cells in the middle to make it actually work.
// Find all the FF outputs
pool<SigBit> sig_fed_by_ff;
for (auto cell : module->selected_cells())
{
if (cell->type.in("\\FDCP", "\\FDCP_N", "\\FDDCP", "\\LDCP", "\\LDCP_N",
"\\FTCP", "\\FTCP_N", "\\FTDCP", "\\FDCPE", "\\FDCPE_N", "\\FDDCPE"))
{
auto output = sigmap(cell->getPort("\\Q")[0]);
sig_fed_by_ff.insert(output);
}
}
// Look at all the FF inputs
for (auto cell : module->selected_cells())
{
if (cell->type.in("\\FDCP", "\\FDCP_N", "\\FDDCP", "\\LDCP", "\\LDCP_N",
"\\FTCP", "\\FTCP_N", "\\FTDCP", "\\FDCPE", "\\FDCPE_N", "\\FDDCPE"))
{
SigBit input;
if (cell->type.in("\\FTCP", "\\FTCP_N", "\\FTDCP"))
input = sigmap(cell->getPort("\\T")[0]);
else
input = sigmap(cell->getPort("\\D")[0]);
if (sig_fed_by_ff[input])
{
printf("Buffering input to \"%s\"\n", cell->name.c_str());
auto and_to_xor_wire = module->addWire(NEW_ID);
auto xor_to_ff_wire = module->addWire(NEW_ID);
auto and_cell = module->addCell(NEW_ID, "\\ANDTERM");
and_cell->setParam("\\TRUE_INP", 1);
and_cell->setParam("\\COMP_INP", 0);
and_cell->setPort("\\OUT", and_to_xor_wire);
and_cell->setPort("\\IN", input);
and_cell->setPort("\\IN_B", SigSpec());
auto xor_cell = module->addCell(NEW_ID, "\\MACROCELL_XOR");
xor_cell->setParam("\\INVERT_OUT", false);
xor_cell->setPort("\\IN_PTC", and_to_xor_wire);
xor_cell->setPort("\\OUT", xor_to_ff_wire);
if (cell->type.in("\\FTCP", "\\FTCP_N", "\\FTDCP"))
cell->setPort("\\T", xor_to_ff_wire);
else
cell->setPort("\\D", xor_to_ff_wire);
}
}
}
// Actually do the removal now that we aren't iterating
for (auto cell : cells_to_remove)
{
module->remove(cell);
}
}
}
} Coolrunner2SopPass;
PRIVATE_NAMESPACE_END