Merge branch 'q3k/pll-pads' into 'master'

ice40: PLL40_*_PAD support

See merge request SymbioticEDA/nextpnr!21

1 files changed, 6 insertions, 2 deletions

diff --git a/ice40/arch_place.cc b/ice40/arch_place.cc
index 59e1807d..b3404d6c 100644
--- a/ice40/arch_place.cc
+++ b/ice40/arch_place.cc
@@ -124,12 +124,16 @@ bool Arch::isValidBelForCell(CellInfo *cell, BelId bel) const
         }
         // Is there a PLL that shares this IO buffer?
         if (pll_bel.index != -1) {
+            auto pll_cell = getBoundBelCell(pll_bel);
             // Is a PLL placed in this PLL bel?
-            if (!checkBelAvail(pll_bel)) {
+            if (pll_cell != IdString()) {
                 // Is the shared port driving a net?
-                auto pll_cell = getBoundBelCell(pll_bel);
                 auto pi = cells.at(pll_cell)->ports[portPinToId(pll_bel_pin)];
                 if (pi.net != nullptr) {
+                    // Are we perhaps a PAD INPUT Bel that can be placed here?
+                    if (cells.at(pll_cell)->attrs[id("BEL_PAD_INPUT")] == getBelName(bel).str(this)) {
+                        return true;
+                    }
                     return false;
                 }
             }