1 -- `Deep Thought', a softcore CPU implemented on a FPGA
3 -- Copyright (C) 2010 Markus Hofstaetter <markus.manrow@gmx.at>
4 -- Copyright (C) 2010 Martin Perner <e0725782@student.tuwien.ac.at>
5 -- Copyright (C) 2010 Stefan Rebernig <stefan.rebernig@gmail.com>
6 -- Copyright (C) 2010 Manfred Schwarz <e0725898@student.tuwien.ac.at>
7 -- Copyright (C) 2010 Bernhard Urban <lewurm@gmail.com>
9 -- This program is free software: you can redistribute it and/or modify
10 -- it under the terms of the GNU General Public License as published by
11 -- the Free Software Foundation, either version 3 of the License, or
12 -- (at your option) any later version.
14 -- This program is distributed in the hope that it will be useful,
15 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
16 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 -- GNU General Public License for more details.
19 -- You should have received a copy of the GNU General Public License
20 -- along with this program. If not, see <http://www.gnu.org/licenses/>.
23 use IEEE.std_logic_1164.all;
24 use IEEE.numeric_std.all;
26 use work.common_pkg.all;
27 use work.core_pkg.all;
28 use work.extension_pkg.all;
30 entity core_top_c4de2_115 is
34 CLOCK_50 : in std_logic;
36 KEY : in std_logic_vector(0 to 3);
39 UART_TXD : out std_logic;
40 UART_RXD : in std_logic;
42 LEDR : out std_logic_vector(0 to 17);
43 LEDG : out std_logic_vector(0 to 8);
45 HEX0 : out std_logic_vector(0 to 6);
46 HEX1 : out std_logic_vector(0 to 6);
47 HEX2 : out std_logic_vector(0 to 6);
48 HEX3 : out std_logic_vector(0 to 6);
51 LCD_DATA_8 : out std_logic_vector(7 downto 0);
52 LCD_BLON : out std_logic;
53 LCD_RW : out std_logic;
54 LCD_EN : out std_logic;
55 LCD_RS : out std_logic;
56 LCD_ON : out std_logic
61 end core_top_c4de2_115;
63 architecture behav of core_top_c4de2_115 is
65 constant SYNC_STAGES : integer := 2;
66 constant RESET_VALUE : std_logic := '0';
68 signal sys_clk, sys_res, soft_res : std_logic;
69 signal bus_tx, bus_rx : std_logic;
70 signal led2 : std_logic;
71 signal sseg0, sseg1, sseg2, sseg3 : std_logic_vector(0 to 6);
73 signal jump_result : instruction_addr_t;
74 signal jump_result_pin : instruction_addr_t;
75 signal prediction_result_pin : instruction_addr_t;
76 signal branch_prediction_bit_pin : std_logic;
77 signal alu_jump_bit_pin : std_logic;
78 signal instruction_pin : instruction_word_t;
79 signal prog_cnt_pin : instruction_addr_t;
81 signal reg_w_addr_pin : std_logic_vector(REG_ADDR_WIDTH-1 downto 0);
82 signal reg_wr_data_pin : gp_register_t;
83 signal reg_we_pin : std_logic;
84 signal to_next_stage : dec_op;
86 signal result_pin : gp_register_t;--reg
87 signal result_addr_pin : gp_addr_t;--reg
88 signal addr_pin : word_t; --memaddr
89 signal data_pin : gp_register_t; --mem data --ureg
90 signal alu_jump_pin : std_logic;--reg
91 signal brpr_pin : std_logic; --reg
92 signal wr_en_pin : std_logic;--regop --reg
93 signal dmem_pin : std_logic;--memop
94 signal dmem_wr_en_pin : std_logic;
95 signal hword_pin : std_logic;
96 signal byte_s_pin : std_logic;
98 signal gpm_in_pin : extmod_rec;
99 signal gpm_out_pin : gp_register_t;
100 signal nop_pin : std_logic;
102 signal sync : std_logic_vector(1 to SYNC_STAGES);
103 signal sync2 : std_logic_vector(1 to SYNC_STAGES);
104 signal sys_res_n, soft_res_n : std_logic;
106 signal int_req : interrupt_t;
108 signal new_im_data : std_logic;
109 signal im_addr, im_data : gp_register_t;
110 -- signal led2 : std_logic;
112 signal vers, vers_nxt : exec2wb_rec;
123 LEDR(1 to 17) <= (others => '0');
124 LEDG <= (others => '0');
131 fetch_st : fetch_stage
140 clk => sys_clk, --: in std_logic;
141 reset => sys_res_n, --: in std_logic;
142 s_reset => soft_res_n,
145 jump_result => jump_result_pin, --: in instruction_addr_t;
146 prediction_result => prediction_result_pin, --: in instruction_addr_t;
147 branch_prediction_bit => branch_prediction_bit_pin, --: in std_logic;
148 alu_jump_bit => alu_jump_bit_pin, --: in std_logic;
150 -- instruction memory program port :D
151 new_im_data_in => new_im_data,
155 instruction => instruction_pin, --: out instruction_word_t
156 prog_cnt => prog_cnt_pin,
160 decode_st : decode_stage
162 -- active reset value
164 -- active logic value
169 clk => sys_clk, --: in std_logic;
170 reset => sys_res_n and soft_res_n, -- : in std_logic;
173 instruction => instruction_pin, --: in instruction_word_t;
174 prog_cnt => prog_cnt_pin,
175 reg_w_addr => reg_w_addr_pin, --: in std_logic_vector(REG_ADDR_WIDTH-1 downto 0);
176 reg_wr_data => reg_wr_data_pin, --: in gp_register_t;
177 reg_we => reg_we_pin, --: in std_logic;
181 branch_prediction_res => prediction_result_pin, --: instruction_word_t;
182 branch_prediction_bit => branch_prediction_bit_pin, --: std_logic
183 to_next_stage => to_next_stage
186 exec_st : execute_stage
187 generic map(RESET_VALUE)
188 port map(sys_clk, sys_res_n and soft_res_n,to_next_stage, reg_wr_data_pin, reg_we_pin, reg_w_addr_pin, gpm_in_pin, result_pin, result_addr_pin,addr_pin,
189 data_pin, alu_jump_pin,brpr_pin, wr_en_pin, dmem_pin,dmem_wr_en_pin,hword_pin,byte_s_pin, gpm_out_pin);
191 writeback_st : writeback_stage
192 generic map(RESET_VALUE, '1', "altera", 434)
193 port map(sys_clk, sys_res_n and soft_res_n, result_pin, result_addr_pin, addr_pin, data_pin, alu_jump_pin, brpr_pin,
194 wr_en_pin, dmem_pin, dmem_wr_en_pin, hword_pin, byte_s_pin,
195 reg_wr_data_pin, reg_we_pin, reg_w_addr_pin, jump_result_pin, alu_jump_bit_pin,bus_tx, bus_rx,
196 new_im_data, im_addr, im_data, sseg0, sseg1, sseg2, sseg3, int_req);
200 syn: process(sys_clk, sys_res)
204 if sys_res = RESET_VALUE then
206 sync <= (others => RESET_VALUE);
208 elsif rising_edge(sys_clk) then
210 for i in 2 to SYNC_STAGES loop
211 sync(i) <= sync(i - 1);
214 sync2(1) <= soft_res;
215 for i in 2 to SYNC_STAGES loop
216 sync2(i) <= sync2(i - 1);
223 sys_res_n <= sync(SYNC_STAGES);
224 soft_res_n <= sync2(SYNC_STAGES);
225 nop_pin <= (alu_jump_bit_pin); -- xor brpr_pin);
226 jump_result <= prog_cnt_pin; --jump_result_pin;