`default_nettype none
//-----------------------------------------------------
// Project Name : Register File
// Function     : Rergiter bank data 
// Description  : This is the main processor
// Coder        : Ivan Rodriguez Ferrandez  AND Alvaro Jover-Alvarez

//***Headers***

//***Module***
module register_data #(
        parameter integer WORD_SIZE = 32,
        parameter integer REGISTERS = 32,
        parameter integer SEGMENTS = 8 ,
        parameter integer REGDIRSIZE = 5,
        parameter integer ECCBITS = 7,
        parameter integer WHISBONE_ADR = 32,
        parameter [31:0]  ADDRBASE     = 32'h3000_0000,
        parameter [31:0]  REGISTERDATA  = ADDRBASE
    )
    (
        `ifdef USE_POWER_PINS
        inout vdda1,	// User area 1 3.3V supply
        inout vdda2,	// User area 2 3.3V supply
        inout vssa1,	// User area 1 analog ground
        inout vssa2,	// User area 2 analog ground
        inout vccd1,	// User area 1 1.8V supply
        inout vccd2,	// User area 2 1.8v supply
        inout vssd1,	// User area 1 digital ground
        inout vssd2,	// User area 2 digital ground
        `endif
        input  clk_i,
        input  rst_i ,
        input  [WORD_SIZE + ECCBITS - 1 : 0] data_to_register_i,
        //input  [((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)) - 1 : 0] data_to_register_i, // 156 interface
        input  [REGDIRSIZE - 1 : 0] register_i ,
        input  [WHISBONE_ADR - 1 : 0] whisbone_addr_i,
        input  operation_type_i,
        input  wregister_i ,
        input  rregister_i ,
        input  valid_i, 
        input  [3 : 0] wstrb_i,
        input  [WORD_SIZE -1 : 0] wdata_i,
        input  wbs_we_i,
        output reg [WORD_SIZE + ECCBITS -1: 0] store_data_o ,
        //output reg [((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)) - 1 : 0] store_data_o , // 156 interface
        output reg ready_o,
        output reg [WORD_SIZE - 1 : 0] rdata_o,
        output reg [1:0] triple_redundat_validation_o
    );

//***Internal logic generated by compiler***  


//***Dumped Internal logic***
    // wires
    wire [WORD_SIZE - 1 : 0] nand_1;
    wire [WORD_SIZE - 1 : 0] nand_2;
    wire [WORD_SIZE - 1 : 0] nand_3;

    wire [WORD_SIZE - 1 : 0] xor_1;
    wire [WORD_SIZE - 1 : 0] xor_2;
    wire [WORD_SIZE - 1 : 0] xor_3;

    wire xor_reduce_1;
    wire xor_reduce_2;
    wire xor_reduce_3;
    wire correted_triple;
    wire uncorreted_triple;

    // register bank
    reg [((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)) - 1 : 0 ] r[0:SEGMENTS-1];

    //triple_redunancy calculation
    assign  nand_1 = rregister_i & operation_type_i ? r[register_i[REGDIRSIZE - 1: 2]][31:0]  ~& r[register_i[REGDIRSIZE - 1: 2]][63:32]: {WORD_SIZE + ECCBITS{1'b0}};
    assign  nand_2 = rregister_i & operation_type_i ? r[register_i[REGDIRSIZE - 1: 2]][63:32] ~& r[register_i[REGDIRSIZE - 1: 2]][95:64]: {WORD_SIZE + ECCBITS{1'b0}};
    assign  nand_3 = rregister_i & operation_type_i ? r[register_i[REGDIRSIZE - 1: 2]][31:0]  ~& r[register_i[REGDIRSIZE - 1: 2]][95:64]: {WORD_SIZE + ECCBITS{1'b0}};

    //triple_redunancy status
    assign  xor_1 = rregister_i & operation_type_i ?  r[register_i[REGDIRSIZE - 1: 2]][31:0]  ^ r[register_i[REGDIRSIZE - 1: 2]][63:32] : {WORD_SIZE + ECCBITS{1'b0}};
    assign  xor_2 = rregister_i & operation_type_i ?  r[register_i[REGDIRSIZE - 1: 2]][63:32] ^ r[register_i[REGDIRSIZE - 1: 2]][95:64]: {WORD_SIZE + ECCBITS{1'b0}};
    assign  xor_3 = rregister_i & operation_type_i ?  r[register_i[REGDIRSIZE - 1: 2]][31:0]  ^ r[register_i[REGDIRSIZE - 1: 2]][95:64]: {WORD_SIZE + ECCBITS{1'b0}};
    
    assign xor_reduce_1 = |xor_1;
    assign xor_reduce_2 = |xor_2;
    assign xor_reduce_3 = |xor_3;

    always @(posedge clk_i) begin
        // calculate last parity bit
        if (rst_i) begin

            r[0] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[1] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[2] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[3] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[4] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[5] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[6] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            r[7] = {((REGISTERS/ SEGMENTS) * (WORD_SIZE + ECCBITS)){1'b0}};
            ready_o <= 1'b0;
            store_data_o <= {WORD_SIZE + ECCBITS{1'b0}};
            triple_redundat_validation_o <= 2'b00;
        end
        else if (rregister_i & ~operation_type_i) begin
            case (register_i[1:0])
                2'b00: begin
                store_data_o <= r[register_i[REGDIRSIZE - 1: 2]][38:0];
                end
                2'b01: begin
                store_data_o <= r[register_i[REGDIRSIZE - 1: 2]][77:39];
                end
                2'b10: begin
                store_data_o <= r[register_i[REGDIRSIZE - 1: 2]][116:78];
                end
                2'b11: begin
                store_data_o <= r[register_i[REGDIRSIZE - 1: 2]][155:117];
                end
            endcase
            triple_redundat_validation_o <= 2'b00;
            
        end
        else if (rregister_i & operation_type_i) begin
            
            
            triple_redundat_validation_o[0] <= (xor_reduce_1 ^ xor_reduce_2) | (xor_reduce_2 ^ xor_reduce_3);
            triple_redundat_validation_o[1] <= xor_reduce_1 & xor_reduce_2 & xor_reduce_3 ;
            store_data_o[31:0] <= ~(nand_1 & nand_2 & nand_3);

            //store_data_o <= ~((r[register_i[REGDIRSIZE - 1: 2]][31:0] ~& r[register_i[REGDIRSIZE - 1: 2]][63:32]) & (r[register_i[REGDIRSIZE - 1: 2]][63:32] ~& r[register_i[REGDIRSIZE - 1: 2]][95:64]) & (r[register_i[REGDIRSIZE - 1: 2]][31:0] ~& r[register_i[REGDIRSIZE - 1: 2]][95:64]));
        end
        else if (wregister_i & ~operation_type_i) begin
            // Sore data
            case (register_i[1:0])
                2'b00: begin
                r[register_i[REGDIRSIZE - 1: 2]][38:0] <= data_to_register_i;
                end
                2'b01: begin
                r[register_i[REGDIRSIZE - 1: 2]][77:39] <= data_to_register_i;
                end
                2'b10: begin
                r[register_i[REGDIRSIZE - 1: 2]][116:78] <= data_to_register_i;
                end
                2'b11: begin
                r[register_i[REGDIRSIZE - 1: 2]][155:117] <= data_to_register_i;
                end
            endcase
            store_data_o <= {WORD_SIZE + ECCBITS{1'b0}};
            triple_redundat_validation_o <= 2'b00;
        end
        else if (wregister_i & operation_type_i) begin
            r[register_i[REGDIRSIZE - 1: 2]][95:0] <= {data_to_register_i[31:0],data_to_register_i[31:0],data_to_register_i[31:0]};
            store_data_o <= {WORD_SIZE + ECCBITS{1'b0}};
            triple_redundat_validation_o <= 2'b00;
        end
        if (valid_i) begin
            case (whisbone_addr_i)
                REGISTERDATA: begin // the test register is 30 now in order to acomodate testing of the ECC and triple redundacy
                    ready_o <= 1'b1;
                    if (wbs_we_i) begin
                        if (wstrb_i[0]) r[7][85:78]   <= wdata_i[7:0];
                        if (wstrb_i[1]) r[7][93:86]   <= wdata_i[15:8];
                        if (wstrb_i[2]) r[7][101:94]  <= wdata_i[23:16];
                        if (wstrb_i[3]) r[7][109:102] <= wdata_i[31:24];
                    end
                    else begin
                        rdata_o <= {r[7][148:117]};
                    end
                end
                ADDRBASE + 4: begin ready_o <= 1'b1; end
                ADDRBASE + 8: begin ready_o <= 1'b1; end
                ADDRBASE + 16: begin ready_o <= 1'b1; end
                default: ready_o <= 1'b0;
            endcase
        end
    end
        
endmodule