From 67682ecfde9dd289187209f6c4432e0b8c54d998 Mon Sep 17 00:00:00 2001
From: Aadi Desai <21363892+supleed2@users.noreply.github.com>
Date: Wed, 16 Dec 2020 14:07:43 +0000
Subject: [PATCH] Create basic bus memory block

I/O, parameters and initial setup block included
---
 rtl/mips_cpu_bus_memory.v | 48 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 rtl/mips_cpu_bus_memory.v

diff --git a/rtl/mips_cpu_bus_memory.v b/rtl/mips_cpu_bus_memory.v
new file mode 100644
index 0000000..0e103b3
--- /dev/null
+++ b/rtl/mips_cpu_bus_memory.v
@@ -0,0 +1,48 @@
+module mips_cpu_bus_memory( //Avalon memory mapped bus controller (slave)
+    input logic clk,
+    input logic[31:0] address,
+    input logic write,
+    input logic read,
+    output logic waitrequest,
+    input logic[31:0] writedata,
+    input logic[3:0] byteenable,
+    output logic[31:0] readdata
+);
+
+parameter INSTR_INIT_FILE = "";
+parameter DATA_INIT_FILE = "";
+
+reg [31:0] data_memory [0:63]; // location 0x00001000 onwards
+reg [31:0] instr_memory [0:63]; // location 0xBFC00000 onwards
+
+initial begin
+    for (integer i=0; i<$size(data_memory); i++) begin //Initialise data to zero by default
+        data_memory[i] = 0;
+    end
+
+    for (integer i=0; i<$size(instr_memory); i++) begin //Initialise instr to zero by default
+        instr_memory[i] = 0;
+    end
+
+    if (INSTR_INIT_FILE != "") begin //Load instr contents from file if specified
+        $display("RAM: Loading RAM contents from %s", INSTR_INIT_FILE);
+        $readmemh(INSTR_INIT_FILE, instr_memory);
+    end
+
+    for (integer i = 0; i<$size(instr_memory); i++) begin //Read out instr contents to log
+        $display("byte +%h: %h", 32'hBFC00000+i*4, instr_memory[i]);
+    end
+
+    if (DATA_INIT_FILE != "") begin //Load data contents from file if specified
+        $display("MEM: Loading MEM contents from %s", DATA_INIT_FILE);
+        $readmemh(DATA_INIT_FILE, data_memory);
+    end else begin
+        $display("MEM FILE NOT GIVEN");
+    end
+
+    for (integer i = 0; i<$size(data_memory); i++) begin //Read out data contents to log
+        $display("byte +%h: %h", 32'h00001000+i*4, data_memory[i]);
+    end
+end
+
+endmodule
\ No newline at end of file