yosys/passes/techmap/dfflibmap.cc

539 lines
17 KiB
C++

/*
* 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/register.h"
#include "kernel/log.h"
#include "libparse.h"
#include <string.h>
using namespace PASS_DFFLIBMAP;
struct cell_mapping {
std::string cell_name;
std::map<std::string, char> ports;
};
static std::map<std::string, cell_mapping> cell_mappings;
static void logmap(std::string dff)
{
if (cell_mappings.count(dff) == 0) {
log(" unmapped dff cell: %s\n", dff.c_str());
} else {
log(" %s %s (", cell_mappings[dff].cell_name.c_str(), dff.substr(1).c_str());
bool first = true;
for (auto &port : cell_mappings[dff].ports) {
char arg[3] = { port.second, 0, 0 };
if ('a' <= arg[0] && arg[0] <= 'z')
arg[1] = arg[0] - ('a' - 'A'), arg[0] = '~';
else
arg[1] = arg[0], arg[0] = ' ';
log("%s.%s(%s)", first ? "" : ", ", port.first.c_str(), arg);
first = false;
}
log(");\n");
}
}
static void logmap_all()
{
logmap("$_DFF_N_");
logmap("$_DFF_P_");
logmap("$_DFF_NN0_");
logmap("$_DFF_NN1_");
logmap("$_DFF_NP0_");
logmap("$_DFF_NP1_");
logmap("$_DFF_PN0_");
logmap("$_DFF_PN1_");
logmap("$_DFF_PP0_");
logmap("$_DFF_PP1_");
logmap("$_DFFSR_NNN_");
logmap("$_DFFSR_NNP_");
logmap("$_DFFSR_NPN_");
logmap("$_DFFSR_NPP_");
logmap("$_DFFSR_PNN_");
logmap("$_DFFSR_PNP_");
logmap("$_DFFSR_PPN_");
logmap("$_DFFSR_PPP_");
}
static bool parse_pin(LibertyAst *cell, LibertyAst *attr, std::string &pin_name, bool &pin_pol)
{
if (cell == NULL || attr == NULL || attr->value.empty())
return false;
std::string value = attr->value;
for (size_t pos = value.find_first_of("\" \t()"); pos != std::string::npos; pos = value.find_first_of("\" \t()"))
value.erase(pos, 1);
if (value[value.size()-1] == '\'') {
pin_name = value.substr(0, value.size()-1);
pin_pol = false;
} else if (value[0] == '!') {
pin_name = value.substr(1, value.size()-1);
pin_pol = false;
} else {
pin_name = value;
pin_pol = true;
}
for (auto child : cell->children)
if (child->id == "pin" && child->args.size() == 1 && child->args[0] == pin_name)
return true;
return false;
}
static void find_cell(LibertyAst *ast, std::string cell_type, bool clkpol, bool has_reset, bool rstpol, bool rstval)
{
LibertyAst *best_cell = NULL;
std::map<std::string, char> best_cell_ports;
int best_cell_pins = 0;
float best_cell_area = 0;
if (ast->id != "library")
log_error("Format error in liberty file.\n");
for (auto cell : ast->children)
{
if (cell->id != "cell" || cell->args.size() != 1)
continue;
LibertyAst *ff = cell->find("ff");
if (ff == NULL)
continue;
std::string cell_clk_pin, cell_rst_pin, cell_next_pin;
bool cell_clk_pol, cell_rst_pol, cell_next_pol;
if (!parse_pin(cell, ff->find("clocked_on"), cell_clk_pin, cell_clk_pol) || cell_clk_pol != clkpol)
continue;
if (!parse_pin(cell, ff->find("next_state"), cell_next_pin, cell_next_pol))
continue;
if (has_reset && rstval == false) {
if (!parse_pin(cell, ff->find("clear"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}
if (has_reset && rstval == true) {
if (!parse_pin(cell, ff->find("preset"), cell_rst_pin, cell_rst_pol) || cell_rst_pol != rstpol)
continue;
}
std::map<std::string, char> this_cell_ports;
this_cell_ports[cell_clk_pin] = 'C';
if (has_reset)
this_cell_ports[cell_rst_pin] = 'R';
this_cell_ports[cell_next_pin] = 'D';
float area = 0;
LibertyAst *ar = cell->find("area");
if (ar != NULL && !ar->value.empty())
area = atof(ar->value.c_str());
int num_pins = 0;
bool found_output = false;
for (auto pin : cell->children)
{
if (pin->id != "pin" || pin->args.size() != 1)
continue;
LibertyAst *dir = pin->find("direction");
if (dir == NULL || dir->value == "internal")
continue;
num_pins++;
if (dir->value == "input" && this_cell_ports.count(pin->args[0]) == 0)
goto continue_cell_loop;
LibertyAst *func = pin->find("function");
if (dir->value == "output" && func != NULL) {
std::string value = func->value;
for (size_t pos = value.find_first_of("\" \t"); pos != std::string::npos; pos = value.find_first_of("\" \t"))
value.erase(pos, 1);
if ((cell_next_pol == true && value == ff->args[0]) || (cell_next_pol == false && value == ff->args[1])) {
this_cell_ports[pin->args[0]] = 'Q';
found_output = true;
}
}
if (this_cell_ports.count(pin->args[0]) == 0)
this_cell_ports[pin->args[0]] = 0;
}
if (!found_output || (best_cell != NULL && num_pins > best_cell_pins))
continue;
if (best_cell != NULL && num_pins == best_cell_pins && area > best_cell_area)
continue;
best_cell = cell;
best_cell_pins = num_pins;
best_cell_area = area;
best_cell_ports.swap(this_cell_ports);
continue_cell_loop:;
}
if (best_cell != NULL) {
log(" cell %s (pins=%d, area=%.2f) is a direct match for cell type %s.\n", best_cell->args[0].c_str(), best_cell_pins, best_cell_area, cell_type.substr(1).c_str());
cell_mappings[cell_type].cell_name = best_cell->args[0];
cell_mappings[cell_type].ports = best_cell_ports;
}
}
static void find_cell_sr(LibertyAst *ast, std::string cell_type, bool clkpol, bool setpol, bool clrpol)
{
LibertyAst *best_cell = NULL;
std::map<std::string, char> best_cell_ports;
int best_cell_pins = 0;
float best_cell_area = 0;
if (ast->id != "library")
log_error("Format error in liberty file.\n");
for (auto cell : ast->children)
{
if (cell->id != "cell" || cell->args.size() != 1)
continue;
LibertyAst *ff = cell->find("ff");
if (ff == NULL)
continue;
std::string cell_clk_pin, cell_set_pin, cell_clr_pin, cell_next_pin;
bool cell_clk_pol, cell_set_pol, cell_clr_pol, cell_next_pol;
if (!parse_pin(cell, ff->find("clocked_on"), cell_clk_pin, cell_clk_pol) || cell_clk_pol != clkpol)
continue;
if (!parse_pin(cell, ff->find("next_state"), cell_next_pin, cell_next_pol))
continue;
if (!parse_pin(cell, ff->find("preset"), cell_set_pin, cell_set_pol) || cell_set_pol != setpol)
continue;
if (!parse_pin(cell, ff->find("clear"), cell_clr_pin, cell_clr_pol) || cell_clr_pol != clrpol)
continue;
std::map<std::string, char> this_cell_ports;
this_cell_ports[cell_clk_pin] = 'C';
this_cell_ports[cell_set_pin] = 'S';
this_cell_ports[cell_clr_pin] = 'R';
this_cell_ports[cell_next_pin] = 'D';
float area = 0;
LibertyAst *ar = cell->find("area");
if (ar != NULL && !ar->value.empty())
area = atof(ar->value.c_str());
int num_pins = 0;
bool found_output = false;
for (auto pin : cell->children)
{
if (pin->id != "pin" || pin->args.size() != 1)
continue;
LibertyAst *dir = pin->find("direction");
if (dir == NULL || dir->value == "internal")
continue;
num_pins++;
if (dir->value == "input" && this_cell_ports.count(pin->args[0]) == 0)
goto continue_cell_loop;
LibertyAst *func = pin->find("function");
if (dir->value == "output" && func != NULL) {
std::string value = func->value;
for (size_t pos = value.find_first_of("\" \t"); pos != std::string::npos; pos = value.find_first_of("\" \t"))
value.erase(pos, 1);
if ((cell_next_pol == true && value == ff->args[0]) || (cell_next_pol == false && value == ff->args[1])) {
this_cell_ports[pin->args[0]] = 'Q';
found_output = true;
}
}
if (this_cell_ports.count(pin->args[0]) == 0)
this_cell_ports[pin->args[0]] = 0;
}
if (!found_output || (best_cell != NULL && num_pins > best_cell_pins))
continue;
if (best_cell != NULL && num_pins == best_cell_pins && area > best_cell_area)
continue;
best_cell = cell;
best_cell_pins = num_pins;
best_cell_area = area;
best_cell_ports.swap(this_cell_ports);
continue_cell_loop:;
}
if (best_cell != NULL) {
log(" cell %s (pins=%d, area=%.2f) is a direct match for cell type %s.\n", best_cell->args[0].c_str(), best_cell_pins, best_cell_area, cell_type.substr(1).c_str());
cell_mappings[cell_type].cell_name = best_cell->args[0];
cell_mappings[cell_type].ports = best_cell_ports;
}
}
static bool expand_cellmap_worker(std::string from, std::string to, std::string inv)
{
if (cell_mappings.count(to) > 0)
return false;
log(" create mapping for %s from mapping for %s.\n", to.c_str(), from.c_str());
cell_mappings[to].cell_name = cell_mappings[from].cell_name;
cell_mappings[to].ports = cell_mappings[from].ports;
for (auto &it : cell_mappings[to].ports) {
char cmp_ch = it.second;
if ('a' <= cmp_ch && cmp_ch <= 'z')
cmp_ch -= 'a' - 'A';
if (inv.find(cmp_ch) == std::string::npos)
continue;
if ('a' <= it.second && it.second <= 'z')
it.second -= 'a' - 'A';
else if ('A' <= it.second && it.second <= 'Z')
it.second += 'a' - 'A';
}
return true;
}
static bool expand_cellmap(std::string pattern, std::string inv)
{
std::vector<std::pair<std::string, std::string>> from_to_list;
bool return_status = false;
for (auto &it : cell_mappings) {
std::string from = it.first, to = it.first;
if (from.size() != pattern.size())
continue;
for (size_t i = 0; i < from.size(); i++) {
if (pattern[i] == '*') {
to[i] = from[i] == 'P' ? 'N' :
from[i] == 'N' ? 'P' :
from[i] == '1' ? '0' :
from[i] == '0' ? '1' : '*';
} else
if (pattern[i] != '?' && pattern[i] != from[i])
goto pattern_failed;
}
from_to_list.push_back(std::pair<std::string, std::string>(from, to));
pattern_failed:;
}
for (auto &it : from_to_list)
return_status = return_status || expand_cellmap_worker(it.first, it.second, inv);
return return_status;
}
static void map_sr_to_arst(const char *from, const char *to)
{
if (cell_mappings.count(to) > 0)
return;
char from_clk_pol = from[8], from_set_pol = from[9], from_clr_pol = from[10];
char to_clk_pol = to[6], to_rst_pol = to[7], to_rst_val = to[8];
log_assert(from_clk_pol == to_clk_pol);
log_assert(to_rst_pol == from_set_pol && to_rst_pol == from_clr_pol);
log(" create mapping for %s from mapping for %s.\n", to, from);
cell_mappings[to].cell_name = cell_mappings[from].cell_name;
cell_mappings[to].ports = cell_mappings[from].ports;
for (auto &it : cell_mappings[to].ports)
{
bool is_set_pin = it.second == 'S' || it.second == 's';
bool is_clr_pin = it.second == 'R' || it.second == 'r';
if (!is_set_pin && !is_clr_pin)
continue;
if ((to_rst_val == '0' && is_set_pin) || (to_rst_val == '1' && is_clr_pin))
{
// this is the unused set/clr pin -- deactivate it
if (is_set_pin)
it.second = (from_set_pol == 'P') == (it.second == 'S') ? '0' : '1';
else
it.second = (from_clr_pol == 'P') == (it.second == 'R') ? '0' : '1';
}
else
{
// this is the used set/clr pin -- rename it to 'reset'
if (it.second == 'S')
it.second = 'R';
if (it.second == 's')
it.second = 'r';
}
}
}
static void dfflibmap(RTLIL::Design *design, RTLIL::Module *module)
{
log("Mapping DFF cells in module `%s':\n", module->name.c_str());
std::vector<RTLIL::Cell*> cell_list;
for (auto &it : module->cells) {
if (design->selected(module, it.second) && cell_mappings.count(it.second->type) > 0)
cell_list.push_back(it.second);
}
std::map<std::string, int> stats;
for (auto cell : cell_list) {
cell_mapping &cm = cell_mappings[cell->type];
RTLIL::Cell *new_cell = new RTLIL::Cell;
new_cell->name = cell->name;
new_cell->type = "\\" + cm.cell_name;
for (auto &port : cm.ports) {
RTLIL::SigSpec sig;
if ('A' <= port.second && port.second <= 'Z') {
sig = cell->connections[std::string("\\") + port.second];
} else
if ('a' <= port.second && port.second <= 'z') {
sig = cell->connections[std::string("\\") + char(port.second - ('a' - 'A'))];
RTLIL::Cell *inv_cell = new RTLIL::Cell;
RTLIL::Wire *inv_wire = new RTLIL::Wire;
inv_cell->name = stringf("$dfflibmap$inv$%d", RTLIL::autoidx);
inv_wire->name = stringf("$dfflibmap$sig$%d", RTLIL::autoidx++);
inv_cell->type = "$_INV_";
inv_cell->connections[port.second == 'q' ? "\\Y" : "\\A"] = sig;
sig = RTLIL::SigSpec(inv_wire);
inv_cell->connections[port.second == 'q' ? "\\A" : "\\Y"] = sig;
module->cells[inv_cell->name] = inv_cell;
module->wires[inv_wire->name] = inv_wire;
} else
if (port.second == '0' || port.second == '1') {
sig = RTLIL::SigSpec(port.second == '0' ? 0 : 1, 1);
} else
if (port.second != 0)
log_abort();
new_cell->connections["\\" + port.first] = sig;
}
stats[stringf(" mapped %%d %s cells to %s cells.\n", cell->type.c_str(), new_cell->type.c_str())]++;
module->cells[cell->name] = new_cell;
delete cell;
}
for (auto &stat: stats)
log(stat.first.c_str(), stat.second);
}
struct DfflibmapPass : public Pass {
DfflibmapPass() : Pass("dfflibmap", "technology mapping of flip-flops") { }
virtual void help()
{
log("\n");
log(" dfflibmap -liberty <file> [selection]\n");
log("\n");
log("Map internal flip-flop cells to the flip-flop cells in the technology\n");
log("library specified in the given liberty file.\n");
log("\n");
log("This pass may add inverters as needed. Therefore it is recommended to\n");
log("first run this pass and then map the logic paths to the target technology.\n");
log("\n");
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
log_header("Executing DFFLIBMAP pass (mapping DFF cells to sequential cells from liberty file).\n");
std::string liberty_file;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
std::string arg = args[argidx];
if (arg == "-liberty" && argidx+1 < args.size()) {
liberty_file = args[++argidx];
continue;
}
break;
}
extra_args(args, argidx, design);
if (liberty_file.empty())
log_cmd_error("Missing `-liberty liberty_file' option!\n");
FILE *f = fopen(liberty_file.c_str(), "r");
if (f == NULL)
log_cmd_error("Can't open liberty file `%s': %s\n", liberty_file.c_str(), strerror(errno));
LibertyParer libparser(f);
fclose(f);
find_cell(libparser.ast, "$_DFF_N_", false, false, false, false);
find_cell(libparser.ast, "$_DFF_P_", true, false, false, false);
find_cell(libparser.ast, "$_DFF_NN0_", false, true, false, false);
find_cell(libparser.ast, "$_DFF_NN1_", false, true, false, true);
find_cell(libparser.ast, "$_DFF_NP0_", false, true, true, false);
find_cell(libparser.ast, "$_DFF_NP1_", false, true, true, true);
find_cell(libparser.ast, "$_DFF_PN0_", true, true, false, false);
find_cell(libparser.ast, "$_DFF_PN1_", true, true, false, true);
find_cell(libparser.ast, "$_DFF_PP0_", true, true, true, false);
find_cell(libparser.ast, "$_DFF_PP1_", true, true, true, true);
find_cell_sr(libparser.ast, "$_DFFSR_NNN_", false, false, false);
find_cell_sr(libparser.ast, "$_DFFSR_NNP_", false, false, true);
find_cell_sr(libparser.ast, "$_DFFSR_NPN_", false, true, false);
find_cell_sr(libparser.ast, "$_DFFSR_NPP_", false, true, true);
find_cell_sr(libparser.ast, "$_DFFSR_PNN_", true, false, false);
find_cell_sr(libparser.ast, "$_DFFSR_PNP_", true, false, true);
find_cell_sr(libparser.ast, "$_DFFSR_PPN_", true, true, false);
find_cell_sr(libparser.ast, "$_DFFSR_PPP_", true, true, true);
// try to implement as many cells as possible just by inverting
// the SET and RESET pins. If necessary, implement cell types
// by inverting both D and Q. Only invert clock pins if there
// is no other way of implementing the cell.
while (1)
{
if (expand_cellmap("$_DFF_?*?_", "R") ||
expand_cellmap("$_DFFSR_?*?_", "S") ||
expand_cellmap("$_DFFSR_??*_", "R"))
continue;
if (expand_cellmap("$_DFF_??*_", "DQ"))
continue;
if (expand_cellmap("$_DFF_*_", "C") ||
expand_cellmap("$_DFF_*??_", "C") ||
expand_cellmap("$_DFFSR_*??_", "C"))
continue;
break;
}
map_sr_to_arst("$_DFFSR_NNN_", "$_DFF_NN0_");
map_sr_to_arst("$_DFFSR_NNN_", "$_DFF_NN1_");
map_sr_to_arst("$_DFFSR_NPP_", "$_DFF_NP0_");
map_sr_to_arst("$_DFFSR_NPP_", "$_DFF_NP1_");
map_sr_to_arst("$_DFFSR_PNN_", "$_DFF_PN0_");
map_sr_to_arst("$_DFFSR_PNN_", "$_DFF_PN1_");
map_sr_to_arst("$_DFFSR_PPP_", "$_DFF_PP0_");
map_sr_to_arst("$_DFFSR_PPP_", "$_DFF_PP1_");
log(" final dff cell mappings:\n");
logmap_all();
for (auto &it : design->modules)
if (design->selected(it.second) && !it.second->get_bool_attribute("\\blackbox"))
dfflibmap(design, it.second);
cell_mappings.clear();
}
} DfflibmapPass;