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-rw-r--r--nexus/fasm.cc2
-rw-r--r--nexus/pack.cc234
2 files changed, 234 insertions, 2 deletions
diff --git a/nexus/fasm.cc b/nexus/fasm.cc
index aea57d6a..c4eb9a1b 100644
--- a/nexus/fasm.cc
+++ b/nexus/fasm.cc
@@ -567,7 +567,9 @@ struct NexusFasmWriter
push_bel(bel);
write_enum(cell, "MODE");
write_enum(cell, "IDDRX1_ODDRX1.OUTPUT");
+ write_enum(cell, "IDDRX1_ODDRX1.TRISTATE");
write_enum(cell, "GSR", "DISABLED");
+ write_enum(cell, "TSREG.REGSET", "RESET");
write_cell_muxes(cell);
pop();
}
diff --git a/nexus/pack.cc b/nexus/pack.cc
index 6385121b..6913ef00 100644
--- a/nexus/pack.cc
+++ b/nexus/pack.cc
@@ -1197,10 +1197,10 @@ struct NexusPacker
NetInfo *dout = get_net_or_empty(ci, id_DOUT);
if (dout != nullptr && dout->users.size() == 1)
iob = dout->users.at(0).cell;
- NetInfo *tout = get_net_or_empty(ci, id_DOUT);
+ NetInfo *tout = get_net_or_empty(ci, id_TOUT);
if (tout != nullptr && tout->users.size() == 1)
iob = tout->users.at(0).cell;
- if (iob->type != id_SEIO18_CORE && iob->type != id_SEIO33_CORE && iob->type != id_DIFFIO18_CORE)
+ if (iob == nullptr || (iob->type != id_SEIO18_CORE && iob->type != id_SEIO33_CORE && iob->type != id_DIFFIO18_CORE))
log_error("Failed to find associated IOB for IOLOGIC %s\n", ctx->nameOf(ci));
io_to_iol[iob->name].push_back(ci);
}
@@ -2075,6 +2075,235 @@ struct NexusPacker
}
}
+ // Finds and returns a flip-flop that drives the given port of an IOB cell
+ // If an associated IOLOGIC cell is provided then checks whether the
+ // flip-flop matches its clock and reset.
+ CellInfo* get_ff_for_iob (CellInfo* iob, IdString port, CellInfo* iol) {
+
+ // Get the net
+ NetInfo* net = get_net_or_empty(iob, port);
+ if (net == nullptr) {
+ return nullptr;
+ }
+
+ // Get the flip-flop that drives it
+ CellInfo* ff = net->driver.cell;
+ if (ff->type != id_OXIDE_FF) {
+ return nullptr;
+ }
+
+ // Get clock nets of IOLOGIC and the flip-flop
+ if (iol != nullptr) {
+ NetInfo* iol_c = get_net_or_empty(iol, id_SCLKOUT);
+ NetInfo* ff_c = get_net_or_empty(ff, id_CLK);
+
+ // If one of them is floating or it is not the same net then abort
+ if (iol_c == nullptr || ff_c == nullptr) {
+ return nullptr;
+ }
+ if (iol_c->name != ff_c->name) {
+ return nullptr;
+ }
+ }
+
+ // Get reset nets of IOLOGIC and the flip-flop
+ if (iol != nullptr) {
+ NetInfo* iol_r = get_net_or_empty(iol, id_LSROUT);
+ NetInfo* ff_r = get_net_or_empty(ff, id_LSR);
+
+ // If one of them is floating or it is not the same net then abort.
+ // But both can be floating.
+ if (!(iol_r == nullptr && ff_r == nullptr)) {
+ if (iol_r == nullptr || ff_r == nullptr) {
+ return nullptr;
+ }
+ if (iol_r->name != ff_r->name) {
+ return nullptr;
+ }
+ }
+ }
+
+ // FIXME: Check if the flip-flop has:
+ // - non-inverted clock
+ // - same reset "type" as ODDR
+ // - others ?
+
+ return ff;
+ }
+
+ // IOLOGIC requires some special handling around itself and IOB. This
+ // function does that.
+ void handle_iologic() {
+ log_info("Packing IOLOGIC...\n");
+
+ // Map of flip-flop cells that drive IOLOGIC+IOB pairs
+ dict<IdString, std::vector<std::pair<IdString,IdString>>> tff_map;
+
+ for (auto &cell : ctx->cells) {
+ CellInfo* iol = cell.second.get();
+ if (iol->type != id_SIOLOGIC && iol->type != id_IOLOGIC) {
+ continue;
+ }
+
+ bool isIDDR = false;
+ bool isODDR = false;
+
+ CellInfo *iob = nullptr;
+ NetInfo *di = get_net_or_empty(iol, id_DI);
+ if (di != nullptr && di->driver.cell != nullptr) {
+ iob = di->driver.cell;
+ isIDDR = true;
+ }
+ NetInfo *dout = get_net_or_empty(iol, id_DOUT);
+ if (dout != nullptr && dout->users.size() == 1) {
+ iob = dout->users.at(0).cell;
+ isODDR = true;
+ }
+ NetInfo *tout = get_net_or_empty(iol, id_TOUT);
+ if (tout != nullptr && tout->users.size() == 1) {
+ iob = tout->users.at(0).cell;
+ isODDR = true; // FIXME: Not sure
+ }
+ NPNR_ASSERT(iob != nullptr);
+
+ // SIOLOGIC handling
+ if (iol->type == id_SIOLOGIC) {
+
+ // We have IDDR+ODDR
+ if (isODDR && isIDDR) {
+ if (!iob->attrs.count(ctx->id("GLITCHFILTER"))) {
+ iob->attrs[ctx->id("GLITCHFILTER")] = std::string("ON");
+ }
+ if (!iob->attrs.count(ctx->id("CLAMP"))) {
+ iob->attrs[ctx->id("CLAMP")] = std::string("ON");
+ }
+ if (!iob->attrs.count(ctx->id("PULLMODE"))) {
+ iob->attrs[ctx->id("PULLMODE")] = std::string("DOWN");
+ }
+ }
+ // We have ODDR only
+ else if (isODDR && !isIDDR) {
+ if (!iob->attrs.count(ctx->id("GLITCHFILTER"))) {
+ iob->attrs[ctx->id("GLITCHFILTER")] = std::string("OFF");
+ }
+ if (!iob->attrs.count(ctx->id("CLAMP"))) {
+ iob->attrs[ctx->id("CLAMP")] = std::string("OFF");
+ }
+ if (!iob->attrs.count(ctx->id("PULLMODE"))) {
+ iob->attrs[ctx->id("PULLMODE")] = std::string("NONE");
+ }
+ }
+
+ // Detect case when SEIO33_CORE.T is not driven by
+ // SIOLOGIC.TOUT. In this case connect SIOLOGIC.TSDATA0 to the
+ // same ned as SEIO33_CORE.I.
+ //
+ //
+ NetInfo* iob_t = get_net_or_empty(iob, id_T);
+ if (iob_t != nullptr && isODDR) {
+ NetInfo* iol_t = get_net_or_empty(iol, id_TOUT);
+
+ // SIOLOGIC.TOUT is not driving SEIO33_CORE.T
+ if ((iol_t == nullptr) ||
+ (iol_t != nullptr && iol_t->users.empty()) ||
+ (iol_t != nullptr && !iol_t->users.empty() && iol_t->name != iob_t->name)) {
+
+ // In this case if SIOLOGIC.TSDATA0 is not connected
+ // to the same net as SEIO33_CORE.T and is not
+ // floating then that configuration is illegal.
+ NetInfo* iol_ti = get_net_or_empty(iol, id_TSDATA0);
+ if (iol_ti != nullptr && (iol_ti->name != iob_t->name)
+ && (iol_ti->name != gnd_net->name))
+ {
+ log_error("Cannot have %s.TSDATA0 and %s.T driven by different nets (%s vs. %s)\n",
+ ctx->nameOf(iol), ctx->nameOf(iob),
+ ctx->nameOf(iol_ti), ctx->nameOf(iob_t));
+ }
+
+ // Re-connect TSDATA (even if it has already been
+ // connected to gnd_net, see the condition above).
+ if (!iol->ports.count(id_TSDATA0)) {
+ iol->addInput(id_TSDATA0);
+ }
+ disconnect_port(ctx, iol, id_TSDATA0);
+ connect_port(ctx, iob_t, iol, id_TSDATA0);
+
+ if (ctx->debug) {
+ log_info(" Reconnecting %s.TSDATA0 to %s\n", ctx->nameOf(iol), ctx->nameOf(iob_t));
+ }
+
+ // Check if the net wants to use the T flip-flop in
+ // IOLOGIC
+ bool syn_useioff = false;
+ if (iob_t->attrs.count(ctx->id("syn_useioff"))) {
+ syn_useioff = iob_t->attrs.at(ctx->id("syn_useioff")).as_bool();
+ }
+
+ // Check if the T input is driven by a flip-flop. Store
+ // in the map for later integration with IOLOGIC.
+ CellInfo* ff = get_ff_for_iob(iob, id_T, iol);
+ if (ff != nullptr && syn_useioff) {
+ tff_map[ff->name].push_back(std::make_pair(
+ iol->name, iob->name));
+ }
+ }
+ }
+ }
+ }
+
+ // Integrate flip-flops that drive T with IOLOGIC
+ for (auto& it : tff_map) {
+ CellInfo* ff = ctx->cells.at(it.first).get();
+
+ NetInfo* ff_d = get_net_or_empty(ff, id_M); // FIXME: id_D or id_M ?!
+ NPNR_ASSERT(ff_d != nullptr);
+
+ NetInfo* ff_q = get_net_or_empty(ff, id_Q);
+ NPNR_ASSERT(ff_q != nullptr);
+
+ for (auto& ios : it.second) {
+ CellInfo* iol = ctx->cells.at(ios.first).get();
+ CellInfo* iob = ctx->cells.at(ios.second).get();
+
+ log_info(" Integrating %s into %s\n", ctx->nameOf(ff), ctx->nameOf(iol));
+
+ // Disconnect "old" T net
+ disconnect_port(ctx, iol, id_TSDATA0);
+ disconnect_port(ctx, iob, id_T);
+
+ // Connect the "new" one
+ connect_port(ctx, ff_d, iol, id_TSDATA0);
+ connect_port(ctx, ff_d, iob, id_T);
+
+ // Propagate parameters
+ iol->params[id_SRMODE] = ff->params.at(id_SRMODE);
+ iol->params[id_REGSET] = ff->params.at(id_REGSET);
+
+ // Enable the TSREG
+ iol->params[ctx->id("CEOUTMUX")] = std::string("1");
+ iol->params[ctx->id("TSREG.REGSET")] = std::string("SET");
+ iol->params[ctx->id("IDDRX1_ODDRX1.TRISTATE")] = std::string("ENABLED");
+ }
+
+ // Disconnect the flip-flop
+ for (auto& port : ff->ports) {
+ disconnect_port(ctx, ff, port.first);
+ }
+
+ // Check if the flip-flop can be removed
+ bool can_remove = ff_q->users.empty();
+
+ // Remove the flip-flop and its output net
+ if (can_remove) {
+ if (ctx->debug) {
+ log_info(" Removing %s\n", ctx->nameOf(ff));
+ }
+ ctx->cells.erase(ff->name);
+ ctx->nets.erase(ff_q->name);
+ }
+ }
+ }
+
explicit NexusPacker(Context *ctx) : ctx(ctx) {}
void operator()()
@@ -2093,6 +2322,7 @@ struct NexusPacker
pack_constants();
pack_luts();
pack_ip();
+ handle_iologic();
promote_globals();
place_globals();
generate_constraints();
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-07 13:48:54 +0000