ice40: Add support for SB_GB_IO

During packing we replace them by standard SB_IO cells and create the
'fake' SB_GB that matches that IO site global buffer connection.

It's done in a separate pass because we need to make sure the nextpnr iob
have been dealt first so we have our final Bel location on the SB_IO.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/ice40/cells.h b/ice40/cells.h
index 7f349020..270292ed 100644
--- a/ice40/cells.h
+++ b/ice40/cells.h
@@ -53,6 +53,9 @@ inline bool is_lc(const BaseCtx *ctx, const CellInfo *cell) { return cell->type
 // Return true if a cell is a SB_IO
 inline bool is_sb_io(const BaseCtx *ctx, const CellInfo *cell) { return cell->type == ctx->id("SB_IO"); }
 
+// Return true if a cell is a SB_GB_IO
+inline bool is_sb_gb_io(const BaseCtx *ctx, const CellInfo *cell) { return cell->type == ctx->id("SB_GB_IO"); }
+
 // Return true if a cell is a global buffer
 inline bool is_gbuf(const BaseCtx *ctx, const CellInfo *cell) { return cell->type == ctx->id("SB_GB"); }