ice40: move PLL->IO from pseudo pip to second uphill bel

1 files changed, 16 insertions, 15 deletions

diff --git a/ice40/bitstream.cc b/ice40/bitstream.cc
index 934cca0c..7c3a26ca 100644
--- a/ice40/bitstream.cc
+++ b/ice40/bitstream.cc
@@ -452,26 +452,27 @@ void write_asc(const Context *ctx, std::ostream &out)
                 if (port.second.net == nullptr)

                     continue;

 

-                // Get IO Bel that this PLL port goes through.

-                // We navigate one pip downhill to the next wire (there should

-                // be only one). Then, the bel that drives that wire should be

-                // the SB_IO that we're looking for.

+                // Get IO Bel that this PLL port goes through by finding sibling

+                // Bel driving the same wire via PIN_D_IN_0.

                 auto wire = ctx->getBelPinWire(cell.second->bel, ctx->portPinFromId(port.second.name));

-                auto pips = ctx->getPipsDownhill(wire).begin();

-                auto driven_wire = ctx->getPipDstWire(*pips);

-                auto io_bel = ctx->chip_info->wire_data[driven_wire.index].bels_uphill[0].bel_index;

-                auto io_beli = ctx->chip_info->bel_data[io_bel];

-                NPNR_ASSERT(io_beli.type == TYPE_SB_IO);

+                BelId io_bel;

+                for (auto pin : ctx->getWireBelPins(wire)) {

+                    if (pin.pin == PIN_D_IN_0) {

+                        io_bel = pin.bel;

+                        break;

+                    }

+                }

+                NPNR_ASSERT(io_bel.index != -1);

+                auto io_bel_loc = ctx->getBelLocation(io_bel);

 

                 // Check that this SB_IO is either unused or just used as an output.

-                auto io_loc = Loc(io_beli.x, io_beli.y, io_beli.z);

-                if (sb_io_used_by_user.count(io_loc)) {

+                if (sb_io_used_by_user.count(io_bel_loc)) {

                     log_error("SB_IO '%s' already in use, cannot route PLL through\n", ctx->getBelName(bel).c_str(ctx));

                 }

-                sb_io_used_by_pll.insert(Loc(io_beli.x, io_beli.y, io_beli.z));

+                sb_io_used_by_pll.insert(io_bel_loc);

 

                 // Get IE/REN config location (cf. http://www.clifford.at/icestorm/io_tile.html)

-                auto ieren = get_ieren(bi, io_beli.x, io_beli.y, io_beli.z);

+                auto ieren = get_ieren(bi, io_bel_loc.x, io_bel_loc.y, io_bel_loc.z);

                 int iex, iey, iez;

                 std::tie(iex, iey, iez) = ieren;

                 NPNR_ASSERT(iez != -1);

@@ -483,8 +484,8 @@ void write_asc(const Context *ctx, std::ostream &out)
                 set_ie_bit_logical(ctx, ti, config.at(iey).at(iex), "IoCtrl.IE_" + std::to_string(iez), true);

                 set_ie_bit_logical(ctx, ti, config.at(iey).at(iex), "IoCtrl.REN_" + std::to_string(iez), false);

                 // PINTYPE[0] passes the PLL through to the fabric.

-                set_config(ti, config.at(io_beli.y).at(io_beli.x), "IOB_" + std::to_string(io_beli.z) + ".PINTYPE_0",

-                           true);

+                set_config(ti, config.at(io_bel_loc.y).at(io_bel_loc.x),

+                           "IOB_" + std::to_string(io_bel_loc.z) + ".PINTYPE_0", true);

             }

 

         } else {