GoWin enablement: DRAM, initial BRAM, DRAM init, DRAM sim and synth_gowin flow

techlibs/gowin/drams_map.v

@@ -0,0 +1,31 @@
+module \$__GW1NR_RAM16S4 (CLK1, A1ADDR, A1DATA, A1EN, B1ADDR, B1DATA, B1EN);
+	parameter CFG_ABITS = 4;
+	parameter CFG_DBITS = 4;
+
+        parameter [63:0] INIT = 64'bx;
+	input CLK1;
+
+	input  [CFG_ABITS-1:0] A1ADDR;
+	output [CFG_DBITS-1:0] A1DATA;   
+        input                  A1EN;
+
+	input  [CFG_ABITS-1:0] B1ADDR;
+	input  [CFG_DBITS-1:0] B1DATA;
+	input  B1EN;
+
+        `include "brams_init3.vh"
+
+  RAM16S4
+   #(.INIT_0(INIT_0),
+     .INIT_1(INIT_1),
+     .INIT_2(INIT_2),
+     .INIT_3(INIT_3))
+   _TECHMAP_REPLACE_
+     (.AD(B1ADDR),
+      .DI(B1DATA),
+      .DO(A1DATA),
+      .CLK(CLK1),
+      .WRE(B1EN));
+
+	
+endmodule