pluto_hdl_adi/library/common/axi_ctrlif.vhd

152 lines
5.6 KiB
VHDL

-- ***************************************************************************
-- ***************************************************************************
-- Copyright 2013(c) Analog Devices, Inc.
-- Author: Lars-Peter Clausen <lars-peter.clausen@analog.com>
--
-- All rights reserved.
--
-- Redistribution and use in source and binary forms, with or without modification,
-- are permitted provided that the following conditions are met:
-- - Redistributions of source code must retain the above copyright
-- notice, this list of conditions and the following disclaimer.
-- - Redistributions in binary form must reproduce the above copyright
-- notice, this list of conditions and the following disclaimer in
-- the documentation and/or other materials provided with the
-- distribution.
-- - Neither the name of Analog Devices, Inc. nor the names of its
-- contributors may be used to endorse or promote products derived
-- from this software without specific prior written permission.
-- - The use of this software may or may not infringe the patent rights
-- of one or more patent holders. This license does not release you
-- from the requirement that you obtain separate licenses from these
-- patent holders to use this software.
-- - Use of the software either in source or binary form, must be run
-- on or directly connected to an Analog Devices Inc. component.
--
-- THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
-- INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A
-- PARTICULAR PURPOSE ARE DISCLAIMED.
--
-- IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-- EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, INTELLECTUAL PROPERTY
-- RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
-- BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
-- STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
-- THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-- ***************************************************************************
-- ***************************************************************************
library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity axi_ctrlif is
generic
(
C_NUM_REG : integer := 32;
C_S_AXI_DATA_WIDTH : integer := 32;
C_S_AXI_ADDR_WIDTH : integer := 32;
C_FAMILY : string := "virtex6"
);
port
(
-- AXI bus interface
S_AXI_ACLK : in std_logic;
S_AXI_ARESETN : in std_logic;
S_AXI_AWADDR : in std_logic_vector(C_S_AXI_ADDR_WIDTH-1 downto 0);
S_AXI_AWVALID : in std_logic;
S_AXI_WDATA : in std_logic_vector(C_S_AXI_DATA_WIDTH-1 downto 0);
S_AXI_WSTRB : in std_logic_vector((C_S_AXI_DATA_WIDTH/8)-1 downto 0);
S_AXI_WVALID : in std_logic;
S_AXI_BREADY : in std_logic;
S_AXI_ARADDR : in std_logic_vector(C_S_AXI_ADDR_WIDTH-1 downto 0);
S_AXI_ARVALID : in std_logic;
S_AXI_RREADY : in std_logic;
S_AXI_ARREADY : out std_logic;
S_AXI_RDATA : out std_logic_vector(C_S_AXI_DATA_WIDTH-1 downto 0);
S_AXI_RRESP : out std_logic_vector(1 downto 0);
S_AXI_RVALID : out std_logic;
S_AXI_WREADY : out std_logic;
S_AXI_BRESP : out std_logic_vector(1 downto 0);
S_AXI_BVALID : out std_logic;
S_AXI_AWREADY : out std_logic;
rd_addr : out integer range 0 to C_NUM_REG - 1;
rd_data : in std_logic_vector(C_S_AXI_DATA_WIDTH-1 downto 0);
rd_ack : out std_logic;
rd_stb : in std_logic;
wr_addr : out integer range 0 to C_NUM_REG - 1;
wr_data : out std_logic_vector(C_S_AXI_DATA_WIDTH-1 downto 0);
wr_ack : in std_logic;
wr_stb : out std_logic
);
end entity axi_ctrlif;
architecture Behavioral of axi_ctrlif is
type state_type is (IDLE, RESP, ACK);
signal rd_state : state_type;
signal wr_state : state_type;
begin
process (S_AXI_ACLK)
begin
if rising_edge(S_AXI_ACLK) then
if S_AXI_ARESETN = '0' then
rd_state <= IDLE;
else
case rd_state is
when IDLE =>
if S_AXI_ARVALID = '1' then
rd_state <= RESP;
rd_addr <= to_integer(unsigned(S_AXI_ARADDR((C_S_AXI_ADDR_WIDTH-1) downto 2)));
end if;
when RESP =>
if rd_stb = '1' and S_AXI_RREADY = '1' then
rd_state <= IDLE;
end if;
when others => null;
end case;
end if;
end if;
end process;
S_AXI_ARREADY <= '1' when rd_state = IDLE else '0';
S_AXI_RVALID <= '1' when rd_state = RESP and rd_stb = '1' else '0';
S_AXI_RRESP <= "00";
rd_ack <= '1' when rd_state = RESP and S_AXI_RREADY = '1' else '0';
S_AXI_RDATA <= rd_data;
process (S_AXI_ACLK)
begin
if rising_edge(S_AXI_ACLK) then
if S_AXI_ARESETN = '0' then
wr_state <= IDLE;
else
case wr_state is
when IDLE =>
if S_AXI_AWVALID = '1' and S_AXI_WVALID = '1' and wr_ack = '1' then
wr_state <= ACK;
end if;
when ACK =>
wr_state <= RESP;
when RESP =>
if S_AXI_BREADY = '1' then
wr_state <= IDLE;
end if;
end case;
end if;
end if;
end process;
wr_stb <= '1' when S_AXI_AWVALID = '1' and S_AXI_WVALID = '1' and wr_state = IDLE else '0';
wr_data <= S_AXI_WDATA;
wr_addr <= to_integer(unsigned(S_AXI_AWADDR((C_S_AXI_ADDR_WIDTH-1) downto 2)));
S_AXI_AWREADY <= '1' when wr_state = ACK else '0';
S_AXI_WREADY <= '1' when wr_state = ACK else '0';
S_AXI_BRESP <= "00";
S_AXI_BVALID <= '1' when wr_state = RESP else '0';
end;