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-rw-r--r--passes/fsm/fsm.cc8
-rw-r--r--passes/fsm/fsm_map.cc56
-rw-r--r--passes/fsm/fsm_recode.cc65
3 files changed, 85 insertions, 44 deletions
diff --git a/passes/fsm/fsm.cc b/passes/fsm/fsm.cc
index c0c42de9..b4d7bc46 100644
--- a/passes/fsm/fsm.cc
+++ b/passes/fsm/fsm.cc
@@ -56,6 +56,7 @@ struct FsmPass : public Pass {
log(" -expand, -norecode, -export, -nomap\n");
log(" enable or disable passes as indicated above\n");
log("\n");
+ log(" -encoding tye\n");
log(" -fm_set_fsm_file file\n");
log(" passed through to fsm_recode pass\n");
log("\n");
@@ -67,6 +68,7 @@ struct FsmPass : public Pass {
bool flag_expand = false;
bool flag_export = false;
std::string fm_set_fsm_file_opt;
+ std::string encoding_opt;
log_header("Executing FSM pass (extract and optimize FSM).\n");
log_push();
@@ -78,6 +80,10 @@ struct FsmPass : public Pass {
fm_set_fsm_file_opt = " -fm_set_fsm_file " + args[++argidx];
continue;
}
+ if (arg == "-encoding" && argidx+1 < args.size() && fm_set_fsm_file_opt.empty()) {
+ encoding_opt = " -encoding " + args[++argidx];
+ continue;
+ }
if (arg == "-norecode") {
flag_norecode = true;
continue;
@@ -112,7 +118,7 @@ struct FsmPass : public Pass {
}
if (!flag_norecode)
- Pass::call(design, "fsm_recode" + fm_set_fsm_file_opt);
+ Pass::call(design, "fsm_recode" + fm_set_fsm_file_opt + encoding_opt);
Pass::call(design, "fsm_info");
if (!flag_nomap)
diff --git a/passes/fsm/fsm_map.cc b/passes/fsm/fsm_map.cc
index 063af587..b8edf420 100644
--- a/passes/fsm/fsm_map.cc
+++ b/passes/fsm/fsm_map.cc
@@ -77,27 +77,30 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
and_sig.append(RTLIL::SigSpec(eq_wire));
}
- if (or_sig.width == 1)
+ if (or_sig.width < num_states-int(fullstate_cache.size()))
{
- and_sig.append(or_sig);
- }
- else if (or_sig.width < num_states && int(it.second.size()) < num_states)
- {
- RTLIL::Wire *or_wire = new RTLIL::Wire;
- or_wire->name = NEW_ID;
- module->add(or_wire);
-
- RTLIL::Cell *or_cell = new RTLIL::Cell;
- or_cell->name = NEW_ID;
- or_cell->type = "$reduce_or";
- or_cell->connections["\\A"] = or_sig;
- or_cell->connections["\\Y"] = RTLIL::SigSpec(or_wire);
- or_cell->parameters["\\A_SIGNED"] = RTLIL::Const(false);
- or_cell->parameters["\\A_WIDTH"] = RTLIL::Const(or_sig.width);
- or_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
- module->add(or_cell);
-
- and_sig.append(RTLIL::SigSpec(or_wire));
+ if (or_sig.width == 1)
+ {
+ and_sig.append(or_sig);
+ }
+ else
+ {
+ RTLIL::Wire *or_wire = new RTLIL::Wire;
+ or_wire->name = NEW_ID;
+ module->add(or_wire);
+
+ RTLIL::Cell *or_cell = new RTLIL::Cell;
+ or_cell->name = NEW_ID;
+ or_cell->type = "$reduce_or";
+ or_cell->connections["\\A"] = or_sig;
+ or_cell->connections["\\Y"] = RTLIL::SigSpec(or_wire);
+ or_cell->parameters["\\A_SIGNED"] = RTLIL::Const(false);
+ or_cell->parameters["\\A_WIDTH"] = RTLIL::Const(or_sig.width);
+ or_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
+ module->add(or_cell);
+
+ and_sig.append(RTLIL::SigSpec(or_wire));
+ }
}
switch (and_sig.width)
@@ -131,7 +134,7 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
cases_vector.append(RTLIL::SigSpec(1, 1));
break;
default:
- assert(!"This should never happen!");
+ log_abort();
}
}
@@ -184,6 +187,9 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
state_dff->type = "$adff";
state_dff->parameters["\\ARST_POLARITY"] = fsm_cell->parameters["\\ARST_POLARITY"];
state_dff->parameters["\\ARST_VALUE"] = fsm_data.state_table[fsm_data.reset_state];
+ for (auto &bit : state_dff->parameters["\\ARST_VALUE"].bits)
+ if (bit != RTLIL::State::S1)
+ bit = RTLIL::State::S0;
state_dff->connections["\\ARST"] = fsm_cell->connections["\\ARST"];
}
state_dff->parameters["\\WIDTH"] = RTLIL::Const(fsm_data.state_bits);
@@ -221,8 +227,7 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
}
else
{
- if (sig_b.as_bool() || sig_b.width != fsm_data.state_bits)
- encoding_is_onehot = false;
+ encoding_is_onehot = false;
RTLIL::Cell *eq_cell = new RTLIL::Cell;
eq_cell->name = NEW_ID;
@@ -266,6 +271,7 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
if (encoding_is_onehot)
{
+ RTLIL::SigSpec next_state_sig(RTLIL::State::Sm, next_state_wire->width);
for (size_t i = 0; i < fsm_data.state_table.size(); i++) {
RTLIL::Const state = fsm_data.state_table[i];
int bit_idx = -1;
@@ -273,8 +279,10 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
if (state.bits[j] == RTLIL::State::S1)
bit_idx = j;
if (bit_idx >= 0)
- module->connections.push_back(RTLIL::SigSig(RTLIL::SigSpec(next_state_wire, 1, bit_idx), RTLIL::SigSpec(next_state_onehot, 1, i)));
+ next_state_sig.replace(bit_idx, RTLIL::SigSpec(next_state_onehot, 1, i));
}
+ log_assert(!next_state_sig.has_marked_bits());
+ module->connections.push_back(RTLIL::SigSig(next_state_wire, next_state_sig));
}
else
{
diff --git a/passes/fsm/fsm_recode.cc b/passes/fsm/fsm_recode.cc
index acb5944a..99ee0eb5 100644
--- a/passes/fsm/fsm_recode.cc
+++ b/passes/fsm/fsm_recode.cc
@@ -23,6 +23,7 @@
#include "kernel/consteval.h"
#include "kernel/celltypes.h"
#include "fsmdata.h"
+#include "math.h"
#include <string.h>
static void fm_set_fsm_print(RTLIL::Cell *cell, RTLIL::Module *module, FsmData &fsm_data, const char *prefix, FILE *f)
@@ -46,31 +47,50 @@ static void fm_set_fsm_print(RTLIL::Cell *cell, RTLIL::Module *module, FsmData &
prefix, RTLIL::unescape_id(module->name).c_str());
}
-static void fsm_recode(RTLIL::Cell *cell, RTLIL::Module *module, FILE *fm_set_fsm_file)
+static void fsm_recode(RTLIL::Cell *cell, RTLIL::Module *module, FILE *fm_set_fsm_file, std::string default_encoding)
{
+ std::string encoding = cell->attributes.count("\\fsm_encoding") ? cell->attributes.at("\\fsm_encoding").str : "auto";
+
+ log("Recoding FSM `%s' from module `%s' using `%s' encoding:\n", cell->name.c_str(), module->name.c_str(), encoding.c_str());
+ if (encoding != "none" && encoding != "one-hot" && encoding != "binary") {
+ if (encoding != "auto")
+ log(" unkown encoding `%s': using auto (%s) instead.\n", encoding.c_str(), default_encoding.c_str());
+ encoding = default_encoding;
+ }
+
+ if (encoding == "none") {
+ log(" nothing to do for encoding `none'.\n");
+ return;
+ }
+
FsmData fsm_data;
fsm_data.copy_from_cell(cell);
- log("Recoding FSM `%s' from module `%s':\n", cell->name.c_str(), module->name.c_str());
-
if (fm_set_fsm_file != NULL)
fm_set_fsm_print(cell, module, fsm_data, "r", fm_set_fsm_file);
- fsm_data.state_bits = fsm_data.state_table.size();
- if (fsm_data.reset_state >= 0)
- fsm_data.state_bits--;
-
- int bit_pos = 0;
- for (size_t i = 0; i < fsm_data.state_table.size(); i++)
+ if (encoding == "one-hot") {
+ fsm_data.state_bits = fsm_data.state_table.size();
+ } else
+ if (encoding == "auto" || encoding == "binary") {
+ fsm_data.state_bits = ceil(log2(fsm_data.state_table.size()));
+ } else
+ log_error("FSM encoding `%s' is not supported!\n", encoding.c_str());
+
+ int state_idx_counter = fsm_data.reset_state >= 0 ? 1 : 0;
+ for (int i = 0; i < int(fsm_data.state_table.size()); i++)
{
+ int state_idx = fsm_data.reset_state == i ? 0 : state_idx_counter++;
RTLIL::Const new_code;
- if (int(i) == fsm_data.reset_state)
- new_code = RTLIL::Const(RTLIL::State::S0, fsm_data.state_bits);
- else {
- RTLIL::Const state_code(RTLIL::State::Sa, fsm_data.state_bits);
- state_code.bits[bit_pos++] = RTLIL::State::S1;
- new_code = state_code;
- }
+
+ if (encoding == "one-hot") {
+ new_code = RTLIL::Const(RTLIL::State::Sa, fsm_data.state_bits);
+ new_code.bits[state_idx] = RTLIL::State::S1;
+ } else
+ if (encoding == "auto" || encoding == "binary") {
+ new_code = RTLIL::Const(state_idx, fsm_data.state_bits);
+ } else
+ log_abort();
log(" %s -> %s\n", fsm_data.state_table[i].as_string().c_str(), new_code.as_string().c_str());
fsm_data.state_table[i] = new_code;
@@ -88,10 +108,12 @@ struct FsmRecodePass : public Pass {
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
- log(" fsm_recode [-fm_set_fsm_file file] [selection]\n");
+ log(" fsm_recode [-encoding type] [-fm_set_fsm_file file] [selection]\n");
log("\n");
log("This pass reassign the state encodings for FSM cells. At the moment only\n");
- log("one-hot encoding is supported.\n");
+ log("one-hot encoding and binary encoding is supported. The option -encoding\n");
+ log("can be used to specify the encoding scheme used for FSMs without the\n");
+ log("`fsm_encoding' attribute (or with the attribute set to `auto'.\n");
log("\n");
log("The option -fm_set_fsm_file can be used to generate a file containing the\n");
log("mapping from old to new FSM encoding in form of Synopsys Formality set_fsm_*\n");
@@ -101,6 +123,7 @@ struct FsmRecodePass : public Pass {
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
FILE *fm_set_fsm_file = NULL;
+ std::string default_encoding = "one-hot";
log_header("Executing FSM_RECODE pass (re-assigning FSM state encoding).\n");
size_t argidx;
@@ -112,6 +135,10 @@ struct FsmRecodePass : public Pass {
log_error("Can't open fm_set_fsm_file `%s' for writing: %s\n", args[argidx].c_str(), strerror(errno));
continue;
}
+ if (arg == "-encoding" && argidx+1 < args.size() && fm_set_fsm_file == NULL) {
+ default_encoding = args[++argidx];
+ continue;
+ }
break;
}
extra_args(args, argidx, design);
@@ -120,7 +147,7 @@ struct FsmRecodePass : public Pass {
if (design->selected(mod_it.second))
for (auto &cell_it : mod_it.second->cells)
if (cell_it.second->type == "$fsm" && design->selected(mod_it.second, cell_it.second))
- fsm_recode(cell_it.second, mod_it.second, fm_set_fsm_file);
+ fsm_recode(cell_it.second, mod_it.second, fm_set_fsm_file, default_encoding);
if (fm_set_fsm_file != NULL)
fclose(fm_set_fsm_file);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-24 13:38:22 +0000