| Line 21... |
Line 21... |
--
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--
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-- Revision:
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-- Revision:
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-- Revision 0.01 - File Created
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-- Revision 0.01 - File Created
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-- Revision 0.02 - Added req for mac tx and wait for grant
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-- Revision 0.02 - Added req for mac tx and wait for grant
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-- Revision 0.03 - Added data_out_first
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-- Revision 0.03 - Added data_out_first
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-- Revision 0.04 - Added arp response timeout
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-- Revision 0.05 - Added arp cache reset control
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-- Additional Comments:
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-- Additional Comments:
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--
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--
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----------------------------------------------------------------------------------
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----------------------------------------------------------------------------------
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library IEEE;
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library IEEE;
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use IEEE.STD_LOGIC_1164.ALL;
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use IEEE.STD_LOGIC_1164.ALL;
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use IEEE.NUMERIC_STD.ALL;
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use IEEE.NUMERIC_STD.ALL;
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use work.arp_types.all;
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use work.arp_types.all;
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entity arp is
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entity arp is
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generic (
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CLOCK_FREQ : integer := 125000000; -- freq of data_in_clk -- needed to timout cntr
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ARP_TIMEOUT : integer := 60 -- ARP response timeout (s)
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);
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Port (
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Port (
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-- lookup request signals
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-- lookup request signals
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arp_req_req : in arp_req_req_type;
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arp_req_req : in arp_req_req_type;
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arp_req_rslt : out arp_req_rslt_type;
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arp_req_rslt : out arp_req_rslt_type;
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-- MAC layer RX signals
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-- MAC layer RX signals
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| Line 53... |
Line 58... |
data_out_last : out std_logic; -- with data out valid indicates the last byte of a frame
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data_out_last : out std_logic; -- with data out valid indicates the last byte of a frame
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data_out : out std_logic_vector (7 downto 0); -- ethernet frame (from dst mac addr through to last byte of frame)
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data_out : out std_logic_vector (7 downto 0); -- ethernet frame (from dst mac addr through to last byte of frame)
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-- system signals
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-- system signals
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our_mac_address : in STD_LOGIC_VECTOR (47 downto 0);
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our_mac_address : in STD_LOGIC_VECTOR (47 downto 0);
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our_ip_address : in STD_LOGIC_VECTOR (31 downto 0);
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our_ip_address : in STD_LOGIC_VECTOR (31 downto 0);
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control : in arp_control_type;
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req_count : out STD_LOGIC_VECTOR(7 downto 0) -- count of arp pkts received
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req_count : out STD_LOGIC_VECTOR(7 downto 0) -- count of arp pkts received
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);
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);
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end arp;
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end arp;
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architecture Behavioral of arp is
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architecture Behavioral of arp is
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type req_state_type is (IDLE,LOOKUP,REQUEST,WAIT_REPLY);
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type req_state_type is (IDLE,LOOKUP,REQUEST,WAIT_REPLY,PAUSE1,PAUSE2,PAUSE3);
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type rx_state_type is (IDLE,PARSE,PROCESS_ARP,WAIT_END);
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type rx_state_type is (IDLE,PARSE,PROCESS_ARP,WAIT_END);
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type rx_event_type is (NO_EVENT,DATA);
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type rx_event_type is (NO_EVENT,DATA);
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type count_mode_type is (RST,INCR,HOLD);
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type count_mode_type is (RST,INCR,HOLD);
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type arp_oper_type is (NOP,REQUEST,REPLY);
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type arp_oper_type is (NOP,REQUEST,REPLY);
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type set_clr_type is (SET, CLR, HOLD);
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type set_clr_type is (SET, CLR, HOLD);
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| Line 83... |
Line 89... |
signal req_ip_addr : std_logic_vector (31 downto 0); -- IP address to lookup
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signal req_ip_addr : std_logic_vector (31 downto 0); -- IP address to lookup
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signal mac_addr_found : STD_LOGIC_VECTOR (47 downto 0); -- mac address found
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signal mac_addr_found : STD_LOGIC_VECTOR (47 downto 0); -- mac address found
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signal mac_addr_valid_reg: std_logic;
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signal mac_addr_valid_reg: std_logic;
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signal send_request_needed : std_logic;
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signal send_request_needed : std_logic;
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signal tx_mac_chn_reqd : std_logic;
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signal tx_mac_chn_reqd : std_logic;
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signal freq_scaler : unsigned (31 downto 0); -- scales data_in_clk downto 1Hz
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signal timer : unsigned (7 downto 0); -- counts seconds timeout
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signal timeout_reg : std_logic;
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signal rx_state : rx_state_type;
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signal rx_state : rx_state_type;
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signal rx_count : unsigned (7 downto 0);
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signal rx_count : unsigned (7 downto 0);
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signal arp_operation : arp_oper_type;
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signal arp_operation : arp_oper_type;
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signal arp_req_count : unsigned (7 downto 0);
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signal arp_req_count : unsigned (7 downto 0);
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| Line 108... |
Line 117... |
signal set_req_ip : std_logic;
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signal set_req_ip : std_logic;
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signal set_mac_addr : std_logic;
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signal set_mac_addr : std_logic;
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signal set_mac_addr_invalid : std_logic;
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signal set_mac_addr_invalid : std_logic;
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signal set_send_req : std_logic;
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signal set_send_req : std_logic;
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signal clear_send_req : std_logic;
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signal clear_send_req : std_logic;
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signal set_timer : count_mode_type; -- timer reset, count, hold control
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signal timer_enable : std_logic; -- enable the timer counting
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signal set_timeout : set_clr_type; -- control the timeout register
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-- rx control signals
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-- rx control signals
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signal next_rx_state : rx_state_type;
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signal next_rx_state : rx_state_type;
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signal set_rx_state : std_logic;
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signal set_rx_state : std_logic;
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| Line 182... |
Line 194... |
req_combinatorial : process (
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req_combinatorial : process (
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-- input signals
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-- input signals
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arp_req_req,
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arp_req_req,
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-- state variables
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-- state variables
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req_state, req_ip_addr, mac_addr_found, mac_addr_valid_reg, send_request_needed, arp_entry,
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req_state, req_ip_addr, mac_addr_found, mac_addr_valid_reg, send_request_needed, arp_entry,
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freq_scaler, timer, timeout_reg,
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-- control signals
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-- control signals
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next_req_state, set_req_state, set_req_ip, set_mac_addr,set_mac_addr_invalid,set_send_req, clear_send_req)
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next_req_state, set_req_state, set_req_ip, set_mac_addr, control,
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set_mac_addr_invalid,set_send_req, clear_send_req, set_timer, timer_enable, set_timeout
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)
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begin
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begin
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-- set output followers
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-- set output followers
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arp_req_rslt.got_err <= '0'; -- errors not returned in this version
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if arp_req_req.lookup_req = '1' then
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arp_req_rslt.got_err <= '0';
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else
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arp_req_rslt.got_err <= timeout_reg;
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end if;
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-- zero time response to lookup request if already in cache
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-- zero time response to lookup request if already in cache
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if arp_req_req.lookup_req = '1' and arp_req_req.ip = arp_entry.ip and arp_entry.is_valid = '1' then
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if arp_req_req.lookup_req = '1' and arp_req_req.ip = arp_entry.ip and arp_entry.is_valid = '1' then
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arp_req_rslt.got_mac <= '1';
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arp_req_rslt.got_mac <= '1';
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arp_req_rslt.mac <= arp_entry.mac;
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arp_req_rslt.mac <= arp_entry.mac;
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elsif arp_req_req.lookup_req = '1' then
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elsif arp_req_req.lookup_req = '1' then
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| Line 207... |
Line 226... |
set_req_ip <= '0';
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set_req_ip <= '0';
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set_mac_addr <= '0';
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set_mac_addr <= '0';
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set_mac_addr_invalid <= '0';
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set_mac_addr_invalid <= '0';
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set_send_req <= '0';
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set_send_req <= '0';
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clear_send_req <= '0';
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clear_send_req <= '0';
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set_timer <= INCR; -- default is timer running, unless we hold or reset it
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set_timeout <= HOLD;
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timer_enable <= '0';
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-- combinatorial logic
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if freq_scaler = x"00000000" then
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timer_enable <= '1';
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end if;
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-- REQ FSM
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-- REQ FSM
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case req_state is
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case req_state is
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when IDLE =>
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when IDLE =>
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set_timer <= RST;
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if arp_req_req.lookup_req = '1' then
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if arp_req_req.lookup_req = '1' then
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-- check if we already have the info in cache
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-- check if we already have the info in cache
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if arp_req_req.ip = arp_entry.ip and arp_entry.is_valid = '1' then
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if arp_req_req.ip = arp_entry.ip and arp_entry.is_valid = '1' then
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-- already have this IP
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-- already have this IP
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set_mac_addr <= '1';
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set_mac_addr <= '1';
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else
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else
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set_timeout <= CLR;
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next_req_state <= LOOKUP;
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next_req_state <= LOOKUP;
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set_req_state <= '1';
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set_req_state <= '1';
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set_req_ip <= '1';
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set_req_ip <= '1';
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set_mac_addr_invalid <= '1';
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set_mac_addr_invalid <= '1';
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end if;
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end if;
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| Line 232... |
Line 261... |
next_req_state <= IDLE;
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next_req_state <= IDLE;
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set_req_state <= '1';
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set_req_state <= '1';
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set_mac_addr <= '1';
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set_mac_addr <= '1';
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else
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else
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-- need to request mac for this IP
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-- need to request mac for this IP
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set_send_req <= '1';
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set_timer <= RST;
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next_req_state <= REQUEST;
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next_req_state <= REQUEST;
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set_req_state <= '1';
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set_req_state <= '1';
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set_send_req <= '1';
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end if;
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end if;
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when REQUEST =>
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when REQUEST =>
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clear_send_req <= '1';
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clear_send_req <= '1';
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next_req_state <= WAIT_REPLY;
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next_req_state <= WAIT_REPLY;
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| Line 248... |
Line 278... |
if arp_entry.is_valid = '1' then
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if arp_entry.is_valid = '1' then
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-- have reply, go back to LOOKUP state to see if it is the right one
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-- have reply, go back to LOOKUP state to see if it is the right one
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next_req_state <= LOOKUP;
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next_req_state <= LOOKUP;
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set_req_state <= '1';
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set_req_state <= '1';
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end if;
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end if;
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-- TODO: add timeout here
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if timer >= ARP_TIMEOUT then
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set_timeout <= SET;
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next_req_state <= PAUSE1;
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set_req_state <= '1';
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end if;
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when PAUSE1 =>
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next_req_state <= PAUSE2;
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set_req_state <= '1';
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when PAUSE2 =>
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next_req_state <= PAUSE3;
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set_req_state <= '1';
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when PAUSE3 =>
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next_req_state <= IDLE;
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set_req_state <= '1';
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end case;
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end case;
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end process;
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end process;
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req_sequential : process (data_in_clk,reset)
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req_sequential : process (data_in_clk,reset)
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| Line 263... |
Line 309... |
req_state <= IDLE;
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req_state <= IDLE;
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req_ip_addr <= (others => '0');
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req_ip_addr <= (others => '0');
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mac_addr_found <= (others => '0');
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mac_addr_found <= (others => '0');
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mac_addr_valid_reg <= '0';
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mac_addr_valid_reg <= '0';
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send_request_needed <= '0';
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send_request_needed <= '0';
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freq_scaler <= to_unsigned(CLOCK_FREQ,32);
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timer <= (others => '0');
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timeout_reg <= '0';
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else
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else
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-- Next req_state processing
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-- Next req_state processing
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if set_req_state = '1' then
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if set_req_state = '1' then
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req_state <= next_req_state;
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req_state <= next_req_state;
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else
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else
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| Line 299... |
Line 348... |
else
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else
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mac_addr_found <= mac_addr_found;
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mac_addr_found <= mac_addr_found;
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mac_addr_valid_reg <= mac_addr_valid_reg;
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mac_addr_valid_reg <= mac_addr_valid_reg;
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end if;
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end if;
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-- freq scaling and 1-sec timer
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if freq_scaler = x"00000000" then
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freq_scaler <= to_unsigned(CLOCK_FREQ,32);
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else
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freq_scaler <= freq_scaler - 1;
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end if;
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-- timer processing
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case set_timer is
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when RST =>
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timer <= x"00";
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when INCR =>
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if timer_enable = '1' then
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timer <= timer + 1;
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else
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timer <= timer;
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end if;
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when HOLD =>
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timer <= timer;
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end case;
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-- timeout latching
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case set_timeout is
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when CLR => timeout_reg <= '0';
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when SET => timeout_reg <= '1';
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when HOLD => timeout_reg <= timeout_reg;
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end case;
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end if;
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end if;
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end if;
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end if;
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end process;
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end process;
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| Line 512... |
Line 589... |
if (set_ip2 = '1') then new_arp_entry.ip(23 downto 16) <= dataval; end if;
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if (set_ip2 = '1') then new_arp_entry.ip(23 downto 16) <= dataval; end if;
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if (set_ip1 = '1') then new_arp_entry.ip(15 downto 8) <= dataval; end if;
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if (set_ip1 = '1') then new_arp_entry.ip(15 downto 8) <= dataval; end if;
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if (set_ip0 = '1') then new_arp_entry.ip(7 downto 0) <= dataval; end if;
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if (set_ip0 = '1') then new_arp_entry.ip(7 downto 0) <= dataval; end if;
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-- set arp entry request
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-- set arp entry request
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if set_arp_entry_request = '1' then
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if control.clear_cache = '1' then
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arp_entry.ip <= x"00000000";
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arp_entry.mac <= x"000000000000";
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arp_entry.is_valid <= '0';
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arp_entry.reply_required <= '0';
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elsif set_arp_entry_request = '1' then
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-- copy info from new entry to arp_entry and set reply required
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-- copy info from new entry to arp_entry and set reply required
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arp_entry.mac <= new_arp_entry.mac;
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arp_entry.mac <= new_arp_entry.mac;
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arp_entry.ip <= new_arp_entry.ip;
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arp_entry.ip <= new_arp_entry.ip;
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arp_entry.is_valid <= '1';
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arp_entry.is_valid <= '1';
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if arp_operation = REQUEST then
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if arp_operation = REQUEST then
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