Add tristates

cells_sim.v

@@ -22,6 +22,30 @@ module GAL_SOP (A, Y);
 	end
 endmodule
 
+module GAL_1SOP (A, Y);
+	parameter WIDTH = 0;
+	parameter DEPTH = 0;
+	parameter TABLE = 0;
+
+	input [WIDTH-1:0] A;
+	output reg Y;
+
+	integer i, j;
+	reg match;
+
+	always @* begin
+		Y = 0;
+		for (i = 0; i < DEPTH; i=i+1) begin
+			match = 1;
+			for (j = 0; j < WIDTH; j=j+1) begin
+				if (TABLE[2*WIDTH*i + 2*j + 0] && A[j]) match = 0;
+				if (TABLE[2*WIDTH*i + 2*j + 1] && !A[j]) match = 0;
+			end
+			if (match) Y = 1;
+		end
+	end
+endmodule
+
 module GAL_INPUT (A, Y);
 	input A;
 	output Y;

extractions/olmc.v

@@ -1,15 +0,0 @@
-module REG_OUT_P (C, A, Y);
-	input C, A;
-	output Y;
-
-	DFF_P dff_p_inst (.C(C), .D(A), .Q(Y));
-	GAL_OUTPUT gal_output_inst (.A(Y));
-endmodule
-
-module REG_OUT_N (C, A, Y);
-	input C, A;
-	output Y;
-
-	NDFF_P dff_p_inst (.C(C), .D(A), .Q(Y));
-	GAL_OUTPUT gal_output_inst (.A(X));
-endmodule

extractions/tristate.v

@@ -0,0 +1,29 @@
+module TRI_DFF_P (C, E, D, Q);
+	input C, E, D;
+	inout Q;
+
+	wire X;
+
+	GAL_TRI gal_tri_inst (.A(X), .E(E), .Y(Q));
+	DFF_P dff_inst (.D(D), .C(C), .Q(X));
+endmodule
+
+module TRI_NDFF_P (C, E, D, Q);
+	input C, E, D;
+	inout Q;
+
+	wire X;
+
+	GAL_TRI gal_tri_inst (.A(X), .E(E), .Y(Q));
+	NDFF_P dff_inst (.D(D), .C(C), .Q(X));
+endmodule
+
+module GAL_TRI_N (C, E, D, Q);
+	input C, E, D;
+	inout Q;
+
+	wire X;
+
+	GAL_TRI gal_tri_inst (.A(X), .E(E), .Y(Q));
+	$_NOT_ not_inst (.A(D), .Y(X));
+endmodule

synth_gal.tcl

@@ -35,9 +35,8 @@ tribuf
 synth
 design -save preop
 
-# Map IO pins (and undo port removal for the output)
+# Map inputs and tristate pins
-iopadmap -bits -inpad GAL_INPUT Y:A -toutpad GAL_OUTPUT E:A:Y -outpad GAL_OUTPUT A
+iopadmap -bits -inpad GAL_INPUT Y:A -toutpad GAL_TRI E:A:Y -tinoutpad GAL_TRI E:Y:A
-expose */t:GAL_OUTPUT "%x:+\[A\]" */t:GAL_OUTPUT %d
 
 ## DFF/SOP mapping
 dfflibmap -liberty techmaps/gal_dff.lib
@@ -71,13 +70,21 @@ techmap -max_iter 1 -map techmaps/trivial_sop.v
 
 # Sequential OLMC 
 extract -constports -map extractions/ndff.v
-extract -constports -map extractions/olmc.v
+extract -constports -map extractions/tristate.v
 techmap -map techmaps/olmc_seq.v
 
+# Make 1SOPs for combinational tristates
+techmap -max_iter 1 -map techmaps/one_sop.v */t:GAL_TRI "%x:+\[E\]" */t:GAL_TRI %d %ci1 */t:GAL_SOP %i
+techmap -max_iter 1 -map techmaps/one_sop.v */t:GAL_TRI_N "%x:+\[E\]" */t:GAL_TRI_N %d %ci1 */t:GAL_SOP %i
+shell
+
 # Add OLMC for internal GAL_SOPs
 #techmap -max_iter 1 -map techmaps/pla_olmc_int.v */t:GAL_OLMC %ci2 */t:GAL_SOP %i */t:GAL_SOP %D
 techmap -max_iter 1 -map techmaps/pla_olmc_int.v */t:GAL_SOP %co1 */w:* %i */t:GAL_SOP %ci1 */w:* %i %i %c %ci1 %D
 
+# Add OLMC for internal GAL_SOPs attached to enable lines
+techmap -max_iter 1 -map techmaps/pla_olmc_int.v */t:GAL_SOP %co1 */w:* %i */t:GAL_OLMC "%ci1:+\[E\]" */w:* %i %i %c %ci1 %D
+
 # Combinational OLMC
 iopadmap -bits -outpad GAL_COMB_OUTPUT_P A:Y */t:GAL_SOP "%x:+\[Y\]" */t:GAL_SOP %d o:* %i
 techmap -map techmaps/olmc_comb.v
@@ -111,7 +118,7 @@ ltp -noff
 design -load postop
 
 ## Print final stats and show graph
-show -width -signed -enum
+show -width -signed
 stat
 
 shell

techmaps/olmc_comb.v

@@ -1,6 +1,7 @@
 (* techmap_celltype = "GAL_COMB_OUTPUT_P" *)
 module _80_GAL_COMB_OUTPUT_P (A, Y);
-	input A, Y;
+	input A;
+	output Y;
 
 	generate
 		GAL_OLMC #(
@@ -17,7 +18,8 @@ endmodule
 
 (* techmap_celltype = "$_NOT_" *)
 module _80_NOT (A, Y);
-	input A, Y;
+	input A;
+	output Y;
 
 	generate
 		GAL_OLMC #(
@@ -31,3 +33,39 @@ module _80_NOT (A, Y);
 		);
 	endgenerate
 endmodule
+
+(* techmap_celltype = "GAL_TRI" *)
+module _80_GAL_TRI (A, E, Y);
+	input A, E;
+	inout Y;
+
+	generate
+		GAL_OLMC #(
+			.REGISTERED(1'b0),
+			.INVERTED(1'b0)
+		) _TECHMAP_REPLACE_ (
+			.C(1'bX),
+			.E(E),
+			.A(A),
+			.Y(Y)
+		);
+	endgenerate
+endmodule
+
+(* techmap_celltype = "GAL_TRI_N" *)
+module _80_GAL_TRI (A, E, Y);
+	input A, E;
+	inout Y;
+
+	generate
+		GAL_OLMC #(
+			.REGISTERED(1'b0),
+			.INVERTED(1'b1)
+		) _TECHMAP_REPLACE_ (
+			.C(1'bX),
+			.E(E),
+			.A(A),
+			.Y(Y)
+		);
+	endgenerate
+endmodule

techmaps/olmc_seq.v

@@ -1,21 +1,3 @@
-(* techmap_celltype = "REG_OUT_P" *)
-module _80_REG_OUT_P (C, A, Y);
-	input C, A;
-	output Y;
-
-	generate
-		GAL_OLMC #(
-			.REGISTERED(1'b1),
-			.INVERTED(1'b0)
-		) _TECHMAP_REPLACE_ (
-			.C(C),
-			.E(1'b1),
-			.A(A),
-			.Y(Y)
-		);
-	endgenerate
-endmodule
-
 (* techmap_celltype = "DFF_P" *)
 module _80_DFF_P (C, D, Q);
 	input C, D;
@@ -34,24 +16,6 @@ module _80_DFF_P (C, D, Q);
 	endgenerate
 endmodule
 
-(* techmap_celltype = "REG_OUT_N" *)
-module _81_REG_OUT_N (C, A, Y);
-	input C, A;
-	output Y;
-
-	generate
-		GAL_OLMC #(
-			.REGISTERED(1'b1),
-			.INVERTED(1'b1)
-		) _TECHMAP_REPLACE_ (
-			.C(C),
-			.E(1'b1),
-			.A(A),
-			.Y(Y)
-		);
-	endgenerate
-endmodule
-
 (* techmap_celltype = "NDFF_P" *)
 module _81_NDFF_P (C, D, Q);
 	input C, D;
@@ -70,9 +34,38 @@ module _81_NDFF_P (C, D, Q);
 	endgenerate
 endmodule
 
-(* techmap_celltype = "GAL_OUTPUT" *)
+(* techmap_celltype = "TRI_DFF_P" *)
-module _82_GAL_OUTPUT (A);
+module _80_TRI_DFF_P (C, E, D, Q);
-	input A;
+	input C, E, D;
+	inout Q;
 
-	// Delete
+	generate
+		GAL_OLMC #(
+			.REGISTERED(1'b1),
+			.INVERTED(1'b0)
+		) _TECHMAP_REPLACE_ (
+			.C(C),
+			.E(E),
+			.A(D),
+			.Y(Q)
+		);
+	endgenerate
+endmodule
+
+(* techmap_celltype = "TRI_NDFF_P" *)
+module _81_TRI_NDFF_P (C, E, D, Q);
+	input C, E, D;
+	inout Q;
+
+	generate
+		GAL_OLMC #(
+			.REGISTERED(1'b1),
+			.INVERTED(1'b1)
+		) _TECHMAP_REPLACE_ (
+			.C(C),
+			.E(E),
+			.A(D),
+			.Y(Q)
+		);
+	endgenerate
 endmodule

techmaps/one_sop.v

@@ -0,0 +1,34 @@
+// Convert GAL_SOPs with only 1 product into a "1SOP"
+// Intended for the enable product
+
+(* techmap_celltype = "GAL_SOP" *)
+module _80_GAL_SOP (A, Y);
+	parameter WIDTH = 0;
+	parameter DEPTH = 0;
+	parameter TABLE = 0;
+
+	input [WIDTH-1:0] A;
+	output reg Y;
+
+	generate
+		if (DEPTH == 1) begin
+			GAL_1SOP #(
+				.WIDTH(WIDTH),
+				.DEPTH(DEPTH),
+				.TABLE(TABLE)
+			) _TECHMAP_REPLACE_ (
+				.A(A),
+				.Y(Y)
+			);
+		end else begin // No-op
+			GAL_SOP #(
+				.WIDTH(WIDTH),
+				.DEPTH(DEPTH),
+				.TABLE(TABLE)
+			) _TECHMAP_REPLACE_ (
+				.A(A),
+				.Y(Y)
+			);
+		end
+	endgenerate
+endmodule

techmaps/tristate.v

@@ -0,0 +1,17 @@
+module GAL_INOUT_TRI(A, E, I, Y);
+	input A, E;
+	output I;
+	inout Y;
+
+	generate
+		GAL_OLMC #(
+			REGISTERED = 0,
+			INVERTED = 0
+		) _TECHMAP_REPLACE_ (
+			.A(A),
+			.C(1'bX),
+			.E(E),
+			.Y(E ? Y : I);
+		);
+	endgenerate
+endmodule

testcases/inout_tristate.v

@@ -0,0 +1,10 @@
+module inout_tristate (
+	input a, b, c,
+	inout y,
+	output z
+);
+
+assign y = c && b ? a && b : 1'bz;
+assign z = c ? a || b : y;
+
+endmodule

testcases/reg_tristate.v

@@ -0,0 +1,14 @@
+module reg_tristate (
+	input clk,
+	input a, b, c,
+	output y
+);
+
+reg x;
+
+assign y = c && b ? x : 1'bz;
+
+always @ (posedge clk)
+	x <= a && b;
+
+endmodule