register file

1 files changed, 41 insertions, 0 deletions

diff --git a/src/register_file.v b/src/register_file.v
new file mode 100644
index 0000000..4f09773
--- /dev/null
+++ b/src/register_file.v
@@ -0,0 +1,41 @@
+module register_file #(
+  parameter N = 32,
+  parameter XLEN = 32
+)(
+  input [CLOG2(XLEN)-1:0] A1, A2, A3,
+  input CLK,
+  input RST,
+  input WE3,
+  input [N-1:0] WD3,
+  output [N-1:0] RD1, RD2
+);
+
+  reg [N-1:0] registers[XLEN-1:0];
+
+  assign RD1 = A1 == 0 ? 0 : registers[A1];
+  assign RD2 = A2 == 0 ? 0 : registers[A2];
+
+  always @ (posedge CLK or negedge RST) begin
+    if (!RST) begin
+      integer i;
+      for (i = 0; i < XLEN; i = i + 1) begin
+        registers[i] <= 0;
+      end
+    end else if (WE3 && (A3 != 0)) begin
+      registers[A3] <= WD3;
+    end
+  end
+
+
+
+  function integer CLOG2(input integer value);
+    integer i;
+    begin
+      value = value - 1;
+      for (i = 0; value > 0; i = i + 1)
+        value = value >> 1;
+      CLOG2 = i;
+    end
+  endfunction
+
+endmodule