Merge pull request #1524 from pepijndevos/gowindffinit

Gowin: add and test DFF init values

3 files changed, 301 insertions, 2 deletions

diff --git a/tests/arch/gowin/adffs.ys b/tests/arch/gowin/adffs.ys
index fc7ee01f2..87fba83a6 100644
--- a/tests/arch/gowin/adffs.ys
+++ b/tests/arch/gowin/adffs.ys
@@ -34,11 +34,12 @@ proc
 equiv_opt -async2sync -assert -map +/gowin/cells_sim.v synth_gowin # equivalency check
 design -load postopt # load the post-opt design (otherwise equiv_opt loads the pre-opt design)
 cd dffs # Constrain all select calls below inside the top module
-select -assert-count 1 t:DFFS
+select -assert-count 1 t:DFF
+select -assert-count 1 t:LUT2
 select -assert-count 4 t:IBUF
 select -assert-count 1 t:OBUF
 
-select -assert-none t:DFFS t:IBUF t:OBUF %% t:* %D
+select -assert-none t:DFF t:LUT2 t:IBUF t:OBUF %% t:* %D
 
 
 design -load read
diff --git a/tests/arch/gowin/init.v b/tests/arch/gowin/init.v
new file mode 100644
index 000000000..3c30f602d
--- /dev/null
+++ b/tests/arch/gowin/init.v
@@ -0,0 +1,224 @@
+module myDFF (output reg Q, input CLK, D);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK)
+		Q <= D;
+endmodule
+
+module myDFFE (output reg Q, input D, CLK, CE);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK) begin
+		if (CE)
+			Q <= D;
+	end
+endmodule // DFFE (positive clock edge; clock enable)
+
+
+module myDFFS (output reg Q, input D, CLK, SET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(posedge CLK) begin
+		if (SET)
+			Q <= 1'b1;
+		else
+			Q <= D;
+	end
+endmodule // DFFS (positive clock edge; synchronous set)
+
+
+module myDFFSE (output reg Q, input D, CLK, CE, SET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(posedge CLK) begin
+		if (SET)
+			Q <= 1'b1;
+		else if (CE)
+			Q <= D;
+end
+endmodule // DFFSE (positive clock edge; synchronous set takes precedence over clock enable)
+
+
+module myDFFR (output reg Q, input D, CLK, RESET);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK) begin
+		if (RESET)
+			Q <= 1'b0;
+		else
+			Q <= D;
+	end
+endmodule // DFFR (positive clock edge; synchronous reset)
+
+
+module myDFFRE (output reg Q, input D, CLK, CE, RESET);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK) begin
+		if (RESET)
+			Q <= 1'b0;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFRE (positive clock edge; synchronous reset takes precedence over clock enable)
+
+
+module myDFFP (output reg Q, input D, CLK, PRESET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(posedge CLK or posedge PRESET) begin
+		if(PRESET)
+			Q <= 1'b1;
+		else
+			Q <= D;
+	end
+endmodule // DFFP (positive clock edge; asynchronous preset)
+
+
+module myDFFPE (output reg Q, input D, CLK, CE, PRESET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(posedge CLK or posedge PRESET) begin
+		if(PRESET)
+			Q <= 1'b1;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFPE (positive clock edge; asynchronous preset; clock enable)
+
+
+module myDFFC (output reg Q, input D, CLK, CLEAR);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK or posedge CLEAR) begin
+		if(CLEAR)
+			Q <= 1'b0;
+		else
+			Q <= D;
+	end
+endmodule // DFFC (positive clock edge; asynchronous clear)
+
+
+module myDFFCE (output reg Q, input D, CLK, CE, CLEAR);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(posedge CLK or posedge CLEAR) begin
+		if(CLEAR)
+			Q <= 1'b0;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFCE (positive clock edge; asynchronous clear; clock enable)
+
+
+module myDFFN (output reg Q, input CLK, D);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK)
+		Q <= D;
+endmodule
+
+module myDFFNE (output reg Q, input D, CLK, CE);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK) begin
+		if (CE)
+			Q <= D;
+	end
+endmodule // DFFNE (negative clock edge; clock enable)
+
+
+module myDFFNS (output reg Q, input D, CLK, SET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(negedge CLK) begin
+		if (SET)
+			Q <= 1'b1;
+		else
+			Q <= D;
+	end
+endmodule // DFFNS (negative clock edge; synchronous set)
+
+
+module myDFFNSE (output reg Q, input D, CLK, CE, SET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(negedge CLK) begin
+		if (SET)
+			Q <= 1'b1;
+		else if (CE)
+			Q <= D;
+end
+endmodule // DFFNSE (negative clock edge; synchronous set takes precedence over clock enable)
+
+
+module myDFFNR (output reg Q, input D, CLK, RESET);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK) begin
+		if (RESET)
+			Q <= 1'b0;
+		else
+			Q <= D;
+	end
+endmodule // DFFNR (negative clock edge; synchronous reset)
+
+
+module myDFFNRE (output reg Q, input D, CLK, CE, RESET);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK) begin
+		if (RESET)
+			Q <= 1'b0;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFNRE (negative clock edge; synchronous reset takes precedence over clock enable)
+
+
+module myDFFNP (output reg Q, input D, CLK, PRESET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(negedge CLK or posedge PRESET) begin
+		if(PRESET)
+			Q <= 1'b1;
+		else
+			Q <= D;
+	end
+endmodule // DFFNP (negative clock edge; asynchronous preset)
+
+
+module myDFFNPE (output reg Q, input D, CLK, CE, PRESET);
+	parameter [0:0] INIT = 1'b1;
+	initial Q = INIT;
+	always @(negedge CLK or posedge PRESET) begin
+		if(PRESET)
+			Q <= 1'b1;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFNPE (negative clock edge; asynchronous preset; clock enable)
+
+
+module myDFFNC (output reg Q, input D, CLK, CLEAR);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK or posedge CLEAR) begin
+		if(CLEAR)
+			Q <= 1'b0;
+		else
+			Q <= D;
+	end
+endmodule // DFFNC (negative clock edge; asynchronous clear)
+
+
+module myDFFNCE (output reg Q, input D, CLK, CE, CLEAR);
+	parameter [0:0] INIT = 1'b0;
+	initial Q = INIT;
+	always @(negedge CLK or posedge CLEAR) begin
+		if(CLEAR)
+			Q <= 1'b0;
+		else if (CE)
+			Q <= D;
+	end
+endmodule // DFFNCE (negative clock edge; asynchronous clear; clock enable)
diff --git a/tests/arch/gowin/init.ys b/tests/arch/gowin/init.ys
new file mode 100644
index 000000000..ddc0e4757
--- /dev/null
+++ b/tests/arch/gowin/init.ys
@@ -0,0 +1,74 @@
+read_verilog init.v
+read_verilog -lib +/gowin/cells_sim.v
+design -save read
+
+proc
+flatten
+synth_gowin -run coarse:
+
+# check if all init values are handled
+check -assert -noinit
+# check if every flop mapped correctly
+select -assert-count 1 t:DFF
+select -assert-count 1 t:DFFC
+select -assert-count 1 t:DFFCE
+select -assert-count 1 t:DFFE
+select -assert-count 1 t:DFFN
+select -assert-count 1 t:DFFNC
+select -assert-count 1 t:DFFNCE
+select -assert-count 1 t:DFFNE
+select -assert-count 1 t:DFFNP
+select -assert-count 1 t:DFFNPE
+select -assert-count 1 t:DFFNR
+select -assert-count 1 t:DFFNRE
+select -assert-count 1 t:DFFNS
+select -assert-count 1 t:DFFNSE
+select -assert-count 1 t:DFFP
+select -assert-count 1 t:DFFPE
+select -assert-count 1 t:DFFR
+select -assert-count 1 t:DFFRE
+select -assert-count 1 t:DFFS
+select -assert-count 1 t:DFFSE
+
+delete
+design -load read
+
+# these should synth to a flop with reset
+chparam -set INIT 1 myDFF myDFFN myDFFE myDFFNE
+
+# async should give a warning
+# sync should synth to a mux
+chparam -set INIT 0 myDFF*S* myDFF*P*
+chparam -set INIT 1 myDFF*R* myDFF*C*
+
+proc
+flatten
+synth_gowin -run coarse:
+
+# check the flops mapped as expected
+select -assert-count 1 t:DFF
+select -assert-count 1 t:DFFC
+select -assert-count 1 t:DFFCE
+select -assert-count 1 t:DFFE
+select -assert-count 1 t:DFFN
+select -assert-count 1 t:DFFNC
+select -assert-count 1 t:DFFNCE
+select -assert-count 1 t:DFFNE
+select -assert-count 1 t:DFFNP
+select -assert-count 1 t:DFFNPE
+select -assert-count 0 t:DFFNR
+select -assert-count 0 t:DFFNRE
+select -assert-count 2 t:DFFNS
+select -assert-count 2 t:DFFNSE
+select -assert-count 1 t:DFFP
+select -assert-count 1 t:DFFPE
+select -assert-count 0 t:DFFR
+select -assert-count 0 t:DFFRE
+select -assert-count 2 t:DFFS
+select -assert-count 2 t:DFFSE
+select -assert-count 12 t:LUT2
+
+# check the expected leftover init values
+# this would happen if your reset value is not the initial value
+# which would be weird
+select -assert-count 8 a:init