/* processor.v - implementation of most functions of the 9086 processor This file is part of the 9086 project. Copyright (c) 2023 Efthymios Kritikos This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ `include "exec_state_def.v" `include "alu_header.v" `include "config.v" `include "ucode_header.v" `include "error_header.v" `define PROC_STATE_BITS 3 `define PROC_RESET 3'b000 `define PROC_DE_STATE_ENTRY 3'b001 `define PROC_HALT 3'b011 //HALT: active high //IOMEM: 1=IO 0=MEM //BHE: active low //write: active low //read: active low //reset: active low module processor ( /* MISC */ input clock, input reset, output wire HALT,output [`ERROR_BITS-1:0] ERROR /* MEMORY / IO */ ,output [19:0] external_address_bus, inout [15:0] external_data_bus,output read, output write,output BHE,output IOMEM `ifdef CALCULATE_IPC /* STATISTICS */ ,output wire new_instruction `endif `ifdef OTUPUT_JSON_STATISTICS /* */ ,output wire [`L1_CACHE_SIZE-1:0] L1_SIZE_STAT, output wire VALID_INSTRUCTION_STAT, output wire jump_req_debug `endif ); `ifdef OTUPUT_JSON_STATISTICS assign jump_req_debug=biu_jump_req; `endif /* If there is an error either from the decoder or execution unit set it to ERROR */ assign ERROR=(DE_ERROR!=`ERR_NO_ERROR)?DE_ERROR:(EXEC_ERROR!=`ERR_NO_ERROR)?EXEC_ERROR:`ERR_NO_ERROR; /*############ Execution Unit ################################################### */ wire [1:0] in_alu_sel1, in_alu_sel2; assign in_alu_sel1 = DE_OUTPUT[44:43]; assign in_alu_sel2 = DE_OUTPUT[46:45]; wire valid_exec_data, set_initial_values; wire [`ERROR_BITS-1:0] EXEC_ERROR; wire use_exec_reg_addr; wire [3:0] EXEC_reg_read_port1_addr; wire [15:0] ALU_O; wire [7:0]EX2DE_FLAGS; wire [15:0] PARAM1_INIT, PARAM2_INIT; assign PARAM1_INIT = DE_OUTPUT[23:8]; assign PARAM2_INIT = DE_OUTPUT[39:24]; wire [2:0] IN_MOD,OUT_MOD; assign IN_MOD=DE_OUTPUT[2:0]; assign OUT_MOD=DE_OUTPUT[49:47]; wire [`ALU_OP_BITS-1:0] ALU_OP; assign ALU_OP = DE_OUTPUT[42:40]; wire [23:0] DE2EX_INSTRUCTION; wire next_exec; execute_unit execute_unit ( /* GENERAL */ clock, reset, Wbit, Sbit, opcode_size, DE2EX_INSTRUCTION[23:0] , valid_exec_data /* */ ,IN_MOD, OUT_MOD,memio_address_select, ProgCount, RM, EXEC_ERROR, write /* */ ,set_initial_values,next_exec /* PARAM */ ,PARAM1_INIT,PARAM2_INIT /* STATE CONTROL */ ,next_state /* ALU CONTROL */ ,in_alu_sel1, in_alu_sel2, ALU_OP, ALU_O /* REGISTER DATA */ ,reg_read_port1_data, reg_read_port2_data, EXEC_reg_read_port1_addr, use_exec_reg_addr, reg_write_we /* FLAGS */ ,EX2DE_FLAGS /* BIU */ ,BIU_ADDRESS_INPUT, biu_write_request, biu_read_request, BIU_VALID_DATA, BIU_DATA, biu_data_direction, biu_jump_req ); /*############ Bus Interface Unit ############################################### */ wire [15:0] INSTRUCTION_LOCATION, BIU_ADDRESS_INPUT; wire [15:0] BIU_DATA; wire [31:0] INSTRUCTION; wire biu_write_request, biu_read_request, BIU_VALID_DATA; wire biu_jump_req, biu_data_direction,VALID_INSTRUCTION; wire VALID_INSTRUCTION_ACK; BIU BIU( /* Outside world */ clock,reset,external_address_bus /* */ ,external_data_bus,read,write,BHE,IOMEM /* Internal */ ,INSTRUCTION,VALID_INSTRUCTION,INSTRUCTION_LOCATION,biu_jump_req /* */ ,BIU_ADDRESS_INPUT,BIU_DATA,biu_write_request,biu_read_request,Wbit,BIU_VALID_DATA,MEM_OR_IO /* */ ,VALID_INSTRUCTION_ACK `ifdef OTUPUT_JSON_STATISTICS /* Statistics */ ,L1_SIZE_STAT, VALID_INSTRUCTION_STAT `endif ); assign BIU_DATA= biu_data_direction ? 16'hz : (memio_address_select ? reg_read_port1_data : ALU_O); /*############ Decoder ########################################################## */ wire [`EXEC_STATE_BITS+`ERROR_BITS+65:0] DE_OUTPUT; decoder decoder( /* GENERAL */ clock, reset, /* INPUT FROM IF */ INSTRUCTION,VALID_INSTRUCTION,INSTRUCTION_LOCATION /* INPUT FROM EX */ ,EX2DE_FLAGS[7:0],next_exec /* OUTPUT TO EX */ ,DE_OUTPUT,DE2EX_INSTRUCTION /* */ ,ProgCount,set_initial_values,valid_exec_data /* OUTPUT TO IF */ ,VALID_INSTRUCTION_ACK `ifdef CALCULATE_IPC /* STATISTICS */ , new_instruction `endif ); wire [2:0] RM; assign RM = DE_OUTPUT[5:3]; wire memio_address_select; assign memio_address_select=DE_OUTPUT[6:6]; wire [3:0] DE_reg_read_port1_addr,DE_reg_read_port2_addr; assign DE_reg_read_port1_addr=DE_OUTPUT[53:50]; assign DE_reg_read_port2_addr=DE_OUTPUT[57:54]; wire [3:0] reg_write_addr; assign reg_write_addr=DE_OUTPUT[61:58]; wire MEM_OR_IO; assign MEM_OR_IO = DE_OUTPUT[7:7]; wire Wbit, Sbit, opcode_size; assign opcode_size=DE_OUTPUT[62:62]; assign Sbit=DE_OUTPUT[63:63]; assign Wbit=DE_OUTPUT[64:64]; wire [`ERROR_BITS-1:0] DE_ERROR; assign HALT = DE_OUTPUT[65:65]; assign DE_ERROR = DE_OUTPUT[`ERROR_BITS+65:66]; wire [`EXEC_STATE_BITS-1:0] next_state; assign next_state=DE_OUTPUT[`EXEC_STATE_BITS+`ERROR_BITS+65:`ERROR_BITS+66]; /*############ Registers ######################################################## */ wire [15:0] ProgCount; wire [3:0] reg_read_port1_addr; assign reg_read_port1_addr = use_exec_reg_addr ? EXEC_reg_read_port1_addr : DE_reg_read_port1_addr; wire [15:0] reg_read_port1_data, reg_read_port2_data; wire reg_write_we; register_file register_file( /* WRITE */ .write_port1_addr(reg_write_addr), /* */ .write_port1_data(ALU_O), /* */ .write_port1_we(reg_write_we), /* READ 1 */ .read_port1_addr(reg_read_port1_addr), /* */ .read_port1_data(reg_read_port1_data), /* READ 2 */ .read_port2_addr(DE_reg_read_port2_addr), /* */ .read_port2_data(reg_read_port2_data) ); /*############################################################################### */ endmodule