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Finished refactoring counter extraction to be nice and generic. Implemented techmapping from $__COUNT_ to GP_COUNTx cells.

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This commit is contained in:
Andrew Zonenberg 2017-08-28 22:13:36 -07:00
parent 46b01f05bb
commit 3fc1b9f3fd
3 changed files with 94 additions and 12 deletions
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36
passes/techmap/extract_counter.cc
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@ -105,15 +105,20 @@ struct CounterExtraction
//attempt to extract a counter centered on the given adder cell
//For now we only support DOWN counters.
//TODO: up/down support
int counter_tryextract(ModIndex& index, Cell *cell, CounterExtraction& extract, pool<RTLIL::IdString>& parallel_cells)
int counter_tryextract(
ModIndex& index,
Cell *cell,
CounterExtraction& extract,
pool<RTLIL::IdString>& parallel_cells,
int maxwidth)
{
SigMap& sigmap = index.sigmap;
//A counter with less than 2 bits makes no sense
//TODO: configurable min/max thresholds
//TODO: configurable min threshold
int a_width = cell->getParam("\\A_WIDTH").as_int();
extract.width = a_width;
if(a_width < 2)
if( (a_width < 2) || (a_width > maxwidth) )
return 1;
//Second input must be a single bit
@ -287,7 +292,8 @@ void counter_worker(
unsigned int& total_counters,
pool<Cell*>& cells_to_remove,
pool<pair<Cell*, string>>& cells_to_rename,
pool<RTLIL::IdString>& parallel_cells)
pool<RTLIL::IdString>& parallel_cells,
int maxwidth)
{
SigMap& sigmap = index.sigmap;
@ -295,8 +301,6 @@ void counter_worker(
if (cell->type != "$alu")
return;
log("Looking at cell %s\n", cell->name.c_str());
//A input is the count value. Check if it has COUNT_EXTRACT set.
//If it's not a wire, don't even try
auto port = sigmap(cell->getPort("\\A"));
@ -336,7 +340,7 @@ void counter_worker(
//Attempt to extract a counter
CounterExtraction extract;
int reason = counter_tryextract(index, cell, extract, parallel_cells);
int reason = counter_tryextract(index, cell, extract, parallel_cells, maxwidth);
//Nonzero code - we could not find a matchable counter.
//Do nothing, unless extraction was forced in which case give an error
@ -414,7 +418,7 @@ void counter_worker(
cell->unsetParam("\\Y_WIDTH");
//Change the cell type
cell->type = "$__COUNT__";
cell->type = "$__COUNT_";
//Hook up resets
if(extract.has_reset)
@ -432,13 +436,13 @@ void counter_worker(
//Hook up other stuff
//cell->setParam("\\CLKIN_DIVIDE", RTLIL::Const(1));
cell->setParam("\\COUNT_TO", RTLIL::Const(extract.count_value));
cell->setParam("\\WIDTH", RTLIL::Const(extract.width));
cell->setPort("\\CLK", extract.clk);
cell->setPort("\\OUT", extract.outsig);
//Hook up hard-wired ports (for now CE and up/=down are not supported), default to no parallel output
cell->setParam("\\HAS_POUT", RTLIL::Const(0));
cell->setParam("\\HAS_CE", RTLIL::Const("NO"));
cell->setParam("\\HAS_CE", RTLIL::Const(0));
cell->setParam("\\DIRECTION", RTLIL::Const("DOWN"));
cell->setPort("\\CE", RTLIL::Const(1));
cell->setPort("\\UP", RTLIL::Const(1));
@ -478,6 +482,8 @@ struct ExtractCounterPass : public Pass {
log("counter cells. Use a target-specific 'techmap' map file to convert those cells\n");
log("to the actual target cells.\n");
log("\n");
log(" -maxwidth N\n");
log(" Only extract counters up to N bits wide\n");
log(" -pout X,Y,...\n");
log(" Only allow parallel output from the counter to the listed cell types\n");
log(" (if not specified, parallel outputs are not restricted)\n");
@ -488,6 +494,7 @@ struct ExtractCounterPass : public Pass {
{
log_header(design, "Executing EXTRACT_COUNTER pass (find counters in netlist).\n");
int maxwidth = 64;
size_t argidx;
pool<RTLIL::IdString> parallel_cells;
for (argidx = 1; argidx < args.size(); argidx++)
@ -513,6 +520,13 @@ struct ExtractCounterPass : public Pass {
tmp += pouts[i];
}
parallel_cells.insert(RTLIL::IdString(tmp));
continue;
}
if (args[argidx] == "-maxwidth" && argidx+1 < args.size())
{
maxwidth = atoi(args[++argidx].c_str());
continue;
}
}
extra_args(args, argidx, design);
@ -526,7 +540,7 @@ struct ExtractCounterPass : public Pass {
ModIndex index(module);
for (auto cell : module->selected_cells())
counter_worker(index, cell, total_counters, cells_to_remove, cells_to_rename, parallel_cells);
counter_worker(index, cell, total_counters, cells_to_remove, cells_to_rename, parallel_cells, maxwidth);
for(auto cell : cells_to_remove)
{