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yannickreiss
2024-08-07 18:30:30 +02:00
parent b3cc87a6d3
commit 1772ac2af2
14 changed files with 249 additions and 218 deletions
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136
src/cpu.vhd
View File

@@ -1,6 +1,6 @@
-- cpu.vhd
-- Created on: Mo 19. Dez 11:07:17 CET 2022
-- Author(s): Yannick Reiß, Carl Ries, Alexander Graf
-- Author(s): Yannick Reiss
-- Content: Entity cpu
library IEEE;
use ieee.std_logic_1164.all;
@@ -12,14 +12,14 @@ use work.riscv_types.all;
-- Entity cpu: path implementation of RISC-V cpu
entity cpu is
port(
clk : in std_logic; -- clk to control the unit
-- Led Output
led : out std_logic_vector(15 downto 0); -- output to 16 LEDS
-- RGB Output
RGB1 : out std_logic_vector(2 downto 0); -- output to RGB 1
RGB2 : out std_logic_vector(2 downto 0) -- output to RGB 2
clk : in std_logic; -- clk to control the unit
rst : in std_logic;
instruction_read : in word;
ram_read_data : in word;
ram_enable_writing : out std_logic;
instruction_pointer : out ram_addr_t;
data_address : out ram_addr_t;
ram_write_data : out word
);
end cpu;
@@ -36,18 +36,6 @@ architecture implementation of cpu is
);
end component;
component ram
port(
clk : in std_logic; -- Clock input for timing
instructionAdr : in ram_addr_t; -- Address instruction
dataAdr : in ram_addr_t; -- Address data
writeEnable : in one_bit; -- Read or write mode
dataIn : in word; -- Write data
instruction : out word; -- Get instruction
dataOut : out word -- Read data
);
end component;
component alu
port (
alu_opc : in aluOP; -- alu opcode.
@@ -69,9 +57,9 @@ architecture implementation of cpu is
component imm
port (
instruction : in instruction;
opcode : in uOP;
immediate : out word
instr : in instruction;
opcode : in uOP;
immediate : out word
);
end component;
@@ -85,8 +73,7 @@ architecture implementation of cpu is
r2_idx : in reg_idx; -- second register to read from
write_enable : in one_bit; -- enable writing to wr_idx
r1_out : out word; -- data from first register
r2_out : out word; -- data from second register
led_out : out word -- output led
r2_out : out word -- data from second register
);
end component;
@@ -100,15 +87,12 @@ architecture implementation of cpu is
end component;
-- SIGNALS GLOBAL
signal s_clock : std_logic;
signal s_reg_wb_enable : one_bit; --enables: register writeback
signal s_reg_wr_enable : one_bit; --enables: register write to index
signal s_pc_enable : one_bit; --enables: pc
signal s_pc_jump_enable : one_bit; --enables: pc jump to address
signal s_ram_enable : one_bit; --enables: ram write enalbe
signal s_led_out : word := "10110011100001110111010110101110"; -- stores the exact output
signal s_clock : std_logic := '0';
signal s_reg_wb_enable : one_bit := "0"; --enables: register writeback
signal s_reg_wr_enable : one_bit := "0"; --enables: register write to index
signal s_pc_enable : one_bit := "0"; --enables: pc
signal s_pc_jump_enable : one_bit := "0"; --enables: pc jump to address
signal s_ram_enable : std_logic := '0'; --enables: ram write enalbe
-- decoder -> registers
signal s_idx_1 : reg_idx;
@@ -122,8 +106,8 @@ architecture implementation of cpu is
signal s_reg_data1 : word;
signal s_reg_data2 : word;
-- pc -> ram
signal s_instAdr : ram_addr_t;
-- pc -> ram
signal s_instAddr : ram_addr_t;
signal s_cycle_cnt : cpuStates := stIF;
signal s_branch_jump_enable : one_bit;
@@ -133,12 +117,10 @@ architecture implementation of cpu is
-- ram -> register
signal s_ram_data : word;
--ram -> decoder + imm
--ram -> decoder + imm
signal s_inst : instruction;
signal s_data_in_addr : ram_addr_t;
-- v dummy signals below v
--imm -> ???
@@ -150,8 +132,8 @@ architecture implementation of cpu is
-- ??? -> alu
signal X_addr_calc : ram_addr_t;
-- Clock signals
signal reset : std_logic;
-- Clock signals
signal reset : std_logic;
signal locked : std_logic;
-------------------------
@@ -167,7 +149,14 @@ architecture implementation of cpu is
begin
s_clock <= clk;
-- External assignments
s_clock <= clk;
ram_enable_writing <= s_ram_enable;
instruction_pointer <= s_instAddr;
data_address <= s_data_in_addr;
ram_write_data <= s_alu_data;
s_inst <= instruction_read;
s_ram_data <= ram_read_data;
decoder_RISCV : decoder
port map(
@@ -188,15 +177,14 @@ begin
r2_idx => s_idx_2,
write_enable => s_reg_wr_enable,
r1_out => s_reg_data1,
r2_out => s_reg_data2,
led_out => s_led_out
r2_out => s_reg_data2
);
imm_RISCV : imm
port map(
instruction => s_inst,
opcode => s_opcode,
immediate => s_immediate
instr => s_inst,
opcode => s_opcode,
immediate => s_immediate
);
pc_RISCV : pc
@@ -205,7 +193,7 @@ begin
en_pc => s_pc_enable,
addr_calc => X_addr_calc,
doJump => s_pc_jump_enable,
addr => s_instAdr
addr => s_instAddr
);
alu_RISCV : alu
@@ -216,17 +204,6 @@ begin
result => s_alu_data
);
ram_RISCV : ram
port map(
clk => s_clock, --
instructionAdr => s_instAdr, -- instruction from pc
dataAdr => s_data_in_addr, -- data address from alu
writeEnable => s_ram_enable, --
dataIn => s_reg_data2, -- data from register
instruction => s_inst, --
dataOut => s_ram_data
);
branch_RISCV : Branch
port map(
op_code => s_opcode,
@@ -243,8 +220,6 @@ begin
-----------------------------------------
-- Output
-----------------------------------------
led <= s_led_out(15 downto 0);
RGB1 <= s_clock & s_clock & s_clock;
alu_control : process (s_immediate, s_opcode, s_reg_data1, s_reg_data2) -- runs only, when item in list changed
begin
@@ -276,8 +251,8 @@ begin
end case;
end process;
-- Process register_data_input select which input is needed for register
register_data_input : process (s_cycle_cnt, s_opcode, s_ram_data, s_alu_data) -- runs only, when item in list changed
-- Process register_data_input select which input is needed for register
register_data_input : process (s_cycle_cnt, s_opcode, s_ram_data, s_alu_data) -- runs only, when item in list changed
begin
s_reg_wb_enable <= "0";
case s_opcode is
@@ -297,43 +272,43 @@ begin
end case;
end process;
-- Process pc input
pc_addr_input : process(s_opcode, s_cycle_cnt, s_instAdr, s_immediate)
-- Process pc input
pc_addr_input : process(s_opcode, s_cycle_cnt, s_instAddr, s_immediate)
begin
if s_cycle_cnt = stWB then
s_pc_enable <= "1";
else
s_pc_enable <= "0";
-- X_addr_calc <= s_instAdr; -- should not be necessary, every case option sets X_addr_calc
-- X_addr_calc <= s_instAddr; -- should not be necessary, every case option sets X_addr_calc
end if;
case s_opcode is
when uJALR | uJAL =>
s_pc_jump_enable <= "1";
X_addr_calc <= std_logic_vector(signed(s_immediate(11 downto 0)) + signed(s_instAdr));
X_addr_calc <= std_logic_vector(signed(s_immediate(11 downto 0)) + signed(s_instAddr));
-- Branch op_codes
when uBEQ | uBNE | uBLT | uBGE | uBLTU | uBGEU =>
-- always load address from immediate on B-Type
X_addr_calc <= std_logic_vector(signed(s_immediate(11 downto 0)) + signed(s_instAdr));
X_addr_calc <= std_logic_vector(signed(s_immediate(11 downto 0)) + signed(s_instAddr));
-- check for opcodes and evaluate condition
s_pc_jump_enable <= s_branch_jump_enable;
when others =>
s_pc_jump_enable <= "0";
X_addr_calc <= s_instAdr;
X_addr_calc <= s_instAddr;
end case;
end process;
-- process ram
-- process ram
ram_input : process(s_opcode, s_cycle_cnt)
begin
s_data_in_addr <= std_logic_vector(signed(s_immediate(11 downto 0)) + signed(s_reg_data1(11 downto 0)));
s_data_in_addr <= std_logic_vector(signed(s_immediate) + signed(s_reg_data1));
if s_cycle_cnt = stWB then
case s_opcode is
when uSB | uSH | uSW => s_ram_enable <= "1";
when others => s_ram_enable <= "0";
when uSB | uSH | uSW => s_ram_enable <= '1';
when others => s_ram_enable <= '0';
end case;
else
s_ram_enable <= "0";
s_ram_enable <= '0';
end if;
end process;
@@ -342,16 +317,11 @@ begin
begin
if rising_edge(s_clock) then
case s_cycle_cnt is
when stIF => s_cycle_cnt <= stDEC;
RGB2 <= "001";
when stDEC => s_cycle_cnt <= stOF;
RGB2 <= "010";
when stOF => s_cycle_cnt <= stEXEC;
RGB2 <= "011";
when stIF => s_cycle_cnt <= stDEC;
when stDEC => s_cycle_cnt <= stOF;
when stOF => s_cycle_cnt <= stEXEC;
when stEXEC => s_cycle_cnt <= stWB;
RGB2 <= "100";
when others => s_cycle_cnt <= stIF;
RGB2 <= "101";
end case;
end if;
end process pc_cycle_control;

34
src/imem.vhd
View File

@@ -13,12 +13,10 @@ entity instr_memory is
generic (initMem : ram_t := (others => (others => '0')));
port (clk : in std_logic;
addr_a : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_a : out std_logic_vector(wordWidth - 1 downto 0);
write_b : in one_bit;
port (clk : in std_logic;
addr_a : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_a : out std_logic_vector(wordWidth - 1 downto 0);
write_b : in std_logic;
addr_b : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_b : out std_logic_vector(wordWidth - 1 downto 0);
data_write_b : in std_logic_vector(wordWidth - 1 downto 0)
@@ -27,28 +25,18 @@ entity instr_memory is
end instr_memory;
-- START:
-- addi x1 x0 1
-- add x2 x0 x0
-- add x3 x0 x0
-- addi x4 x0 2047
-- slli x4 x4 5
-- REG2UP:
-- add x2 x2 x1
-- add x3 x0 x0
-- REG3UP:
-- add x3 x3 x1
-- bgeu x3 x4 REG2UP
-- jal REG3UP
architecture behavioral of instr_memory is
signal store : ram_t :=
(
x"00100093", x"00000133", x"000001b3", x"7ff00213", x"00521213", x"00110133", x"000001b3", x"001181b3", x"fe41fae3", x"ff9ff0ef", others => (others => '0')
b"00000000000000000000001010010011",
b"00000000000100101000001010010011",
b"11111111110111111111000011101111",
others => (others => '0')
);
begin
-- Two synchron read ports
data_read_a <= store(to_integer(unsigned(addr_a(9 downto 2))));
data_read_b <= store(to_integer(unsigned(addr_b(9 downto 2))));
-- Two synchron read ports
data_read_a <= store(to_integer(unsigned(addr_a(ram_addr_size - 3 downto 2))));
data_read_b <= store(to_integer(unsigned(addr_b(ram_addr_size - 3 downto 2))));
end behavioral;

18
src/imm.vhd
View File

@@ -7,9 +7,9 @@ use work.riscv_types.all;
entity imm is
port (
instruction : in instruction;
opcode : in uOP;
immediate : out word
instr : in instruction;
opcode : in uOP;
immediate : out word
);
end imm;
@@ -18,23 +18,23 @@ architecture slicing of imm is
begin
-- Process immediate slice
process (opcode, instruction)
process (opcode, instr)
begin
case opcode is
-- I-Type
when uLB | uLH | uLW | uLBU | uLHU | uADDI | uSLTI | uSLTIU | uXORI | uORI | uANDI => immediate <= std_logic_vector(to_unsigned(0, wordWidth - 12)) & instruction(31 downto 20);
when uLB | uLH | uLW | uLBU | uLHU | uADDI | uSLTI | uSLTIU | uXORI | uORI | uANDI => immediate <= std_logic_vector(to_unsigned(0, wordWidth - 12)) & instr(31 downto 20);
-- S-Type
when uSB | uSH | uSW => immediate <= std_logic_vector(to_unsigned(0, wordWidth-12)) & instruction(31 downto 25) & instruction(11 downto 7);
when uSB | uSH | uSW => immediate <= std_logic_vector(to_unsigned(0, wordWidth-12)) & instr(31 downto 25) & instr(11 downto 7);
-- B-Type
when uBEQ | uBNE | uBLT | uBGE | uBLTU | uBGEU => immediate <= std_logic_vector(to_unsigned(0, 19)) & instruction(31) & instruction(7) & instruction(30 downto 25) & instruction(11 downto 8) & "0";
when uBEQ | uBNE | uBLT | uBGE | uBLTU | uBGEU => immediate <= std_logic_vector(to_unsigned(0, 19)) & instr(31) & instr(7) & instr(30 downto 25) & instr(11 downto 8) & "0";
-- U-Type
when uLUI | uAUIPC => immediate <= instruction(31 downto 12) & std_logic_vector(to_unsigned(0, 12));
when uLUI | uAUIPC => immediate <= instr(31 downto 12) & std_logic_vector(to_unsigned(0, 12));
-- J-Type
when uJAL => immediate <= std_logic_vector(to_unsigned(0, wordWidth - 21)) & instruction(31) & instruction(19 downto 12) & instruction(20) & instruction(30 downto 21) & "0";
when uJAL => immediate <= std_logic_vector(to_unsigned(0, wordWidth - 21)) & instr(31) & instr(19 downto 12) & instr(20) & instr(30 downto 21) & "0";
when others => immediate <= x"C000FFEE";
end case;

82
src/ram_entity_only.vhd → src/ram.vhd
View File

@@ -13,25 +13,23 @@ entity ram is
generic (zeros : ram_t := (others => (others => '0')));
port(
clk : in std_logic; -- Clock input for timing
instructionAdr : in ram_addr_t; -- Address instruction
dataAdr : in ram_addr_t; -- Address data
writeEnable : in one_bit; -- Read or write mode
dataIn : in word; -- Write data
instruction : out word; -- Get instruction
dataOut : out word -- Read data
clk : in std_logic; -- Clock input for timing
instructionAddr : in ram_addr_t; -- Address instruction
dataAddr : in ram_addr_t; -- Address data
writeEnable : in std_logic; -- Read or write mode
dataIn : in word; -- Write data
instruction : out word; -- Get instruction
dataOut : out word -- Read data
);
end ram;
-- Architecture behavioral of ram: control different ram blocks
architecture behavioral of ram is
-- write signals
signal wr1 : one_bit := "0";
signal wr2 : one_bit := "0";
signal wr3 : one_bit := "0";
signal wr4 : one_bit := "0";
signal wr1 : std_logic := '0';
signal wr2 : std_logic := '0';
signal wr3 : std_logic := '0';
signal wr4 : std_logic := '0';
-- instruction signals
signal inst1 : std_logic_vector(wordWidth - 1 downto 0);
@@ -50,9 +48,9 @@ begin
block1 : entity work.instr_memory(behavioral)
port map (
clk => clk,
addr_a => instructionAdr(ram_addr_size - 3 downto 0),
addr_a => instructionAddr(ram_addr_size - 3 downto 0),
write_b => wr1,
addr_b => dataAdr(ram_addr_size - 3 downto 0),
addr_b => dataAddr(ram_addr_size - 3 downto 0),
data_write_b => dataIn,
data_read_a => inst1,
@@ -62,9 +60,9 @@ begin
block2 : entity work.ram_block(behavioral)
port map (
clk => clk,
addr_a => instructionAdr(9 downto 0),
addr_a => instructionAddr(ram_addr_size - 3 downto 0),
write_b => wr2,
addr_b => dataAdr(9 downto 0),
addr_b => dataAddr(ram_addr_size - 3 downto 0),
data_write_b => dataIn,
data_read_a => inst2,
@@ -74,9 +72,9 @@ begin
block3 : entity work.ram_block(behavioral)
port map (
clk => clk,
addr_a => instructionAdr(9 downto 0),
addr_a => instructionAddr(ram_addr_size - 3 downto 0),
write_b => wr3,
addr_b => dataAdr(9 downto 0),
addr_b => dataAddr(ram_addr_size - 3 downto 0),
data_write_b => dataIn,
data_read_a => inst3,
@@ -86,50 +84,50 @@ begin
block4 : entity work.ram_block(behavioral)
port map (
clk => clk,
addr_a => instructionAdr(9 downto 0),
addr_a => instructionAddr(ram_addr_size - 3 downto 0),
write_b => wr4,
addr_b => dataAdr(9 downto 0),
addr_b => dataAddr(ram_addr_size - 3 downto 0),
data_write_b => dataIn,
data_read_a => inst4,
data_read_b => data4
);
addr_block : process (data1, data2, data3, data4, dataAdr(11 downto 10),
addr_block : process (data1, data2, data3, data4, dataAddr(11 downto 10),
inst1, inst2, inst3, inst4,
instructionAdr(11 downto 10), writeEnable) -- run process addr_block when list changes
instructionAddr(11 downto 10), writeEnable) -- run process addr_block when list changes
begin
-- enable write
case dataAdr(11 downto 10) is
case dataAddr(11 downto 10) is
when "00" =>
wr1 <= writeEnable;
wr2 <= "0";
wr3 <= "0";
wr4 <= "0";
wr2 <= '0';
wr3 <= '0';
wr4 <= '0';
when "01" =>
wr1 <= "0";
wr1 <= '0';
wr2 <= writeEnable;
wr3 <= "0";
wr4 <= "0";
wr3 <= '0';
wr4 <= '0';
when "10" =>
wr1 <= "0";
wr2 <= "0";
wr1 <= '0';
wr2 <= '0';
wr3 <= writeEnable;
wr4 <= "0";
wr4 <= '0';
when "11" =>
wr1 <= "0";
wr2 <= "0";
wr3 <= "0";
wr1 <= '0';
wr2 <= '0';
wr3 <= '0';
wr4 <= writeEnable;
when others =>
wr1 <= "0";
wr2 <= "0";
wr3 <= "0";
wr4 <= "0";
wr1 <= '0';
wr2 <= '0';
wr3 <= '0';
wr4 <= '0';
end case;
-- instruction data
case instructionAdr(11 downto 10) is
case instructionAddr(11 downto 10) is
when "00" => instruction <= inst1;
when "01" => instruction <= inst2;
when "10" => instruction <= inst3;
@@ -137,7 +135,7 @@ begin
end case;
-- data data
case dataAdr(11 downto 10) is
case dataAddr(11 downto 10) is
when "00" => dataOut <= data1;
when "01" => dataOut <= data2;
when "10" => dataOut <= data3;

18
src/ram_block.vhd
View File

@@ -13,16 +13,13 @@ entity ram_block is
generic (initMem : ram_t := (others => (others => '0')));
port (clk : in std_logic;
addr_a : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_a : out std_logic_vector(wordWidth - 1 downto 0);
write_b : in one_bit;
port (clk : in std_logic;
addr_a : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_a : out std_logic_vector(wordWidth - 1 downto 0);
write_b : in std_logic;
addr_b : in std_logic_vector(ram_addr_size - 3 downto 0);
data_read_b : out std_logic_vector(wordWidth - 1 downto 0);
data_write_b : in std_logic_vector(wordWidth - 1 downto 0)
);
end ram_block;
@@ -39,16 +36,15 @@ begin
if rising_edge(clk) then
-- One synchron write port
if write_b = "1" then
if write_b = '1' then
store(to_integer(unsigned(addr_b(9 downto 2)))) <= data_write_b;
end if;
end if;
end process;
-- Two synchron read ports
-- Two synchron read ports
data_read_a <= store(to_integer(unsigned(addr_a(9 downto 2))));
data_read_b <= store(to_integer(unsigned(addr_b(9 downto 2))));
data_read_b <= store(to_integer(unsigned(addr_b(5 downto 2))));
end behavioral;

4
src/registers.vhd
View File

@@ -29,8 +29,7 @@ entity registers is
r2_idx : in reg_idx; -- second register to read from
write_enable : in one_bit; -- enable writing to wr_idx
r1_out : out word; -- data from first register
r2_out : out word; -- data from second register
led_out : out word -- output reg 2 to led
r2_out : out word -- data from second register
);
end registers;
@@ -54,6 +53,5 @@ begin
-- read from both reading registers
r1_out <= registerbench(to_integer(unsigned(r1_idx)));
r2_out <= registerbench(to_integer(unsigned(r2_idx)));
led_out <= registerbench(2);
end structure;

11
src/riscv_types.vhd
View File

@@ -52,7 +52,7 @@ package riscv_types is
-- constants for the 7bit opcode field in a normal 32bit instruction.
-- for 32bit size instructions the last 2 bits always have to be '1'
-- for 32bit size instructions the last 2 bits always have to be '1'
-- xxxxx11
constant opc_LUI : opcode := "0110111"; -- load upper immediate
constant opc_AUIPC : opcode := "0010111"; -- add upper immediate to pc
@@ -109,13 +109,12 @@ package riscv_types is
type regFile is array (reg_size - 1 downto 0) of word;
-- ram constants and type
constant ram_size : natural := 4096;
constant ram_block_size : natural := 1024;
constant ram_addr_size : natural := 12;
constant ram_size : natural := 16384;
constant ram_block_size : natural := 4096;
constant ram_addr_size : natural := 32;
subtype ram_addr_t is std_logic_vector(ram_addr_size -1 downto 0);
-- type ram_t is array(0 to ram_addr_size - 1) of word;
type ram_t is array(0 to 255) of word;
type ram_t is array(0 to ram_block_size) of word;
-- const for multiplexer sources
constant mul_wr_alures : two_bit := "00";