[raggedstone] / dhwk / source / pci / config_04h.vhd

-- J.STELZNER
-- INFORMATIK-3 LABOR
-- 23.08.2006
-- File: CONFIG_04H.VHD

library IEEE;
use IEEE.std_logic_1164.all;

entity CONFIG_04H is
        port
        (
                PCI_CLOCK :in std_logic;
                PCI_RSTn :in std_logic;
                SERR :in std_logic;
                PERR :in std_logic;
                AD_REG :in std_logic_vector(31 downto 0);
                CBE_REGn :in std_logic_vector( 3 downto 0);
                CONF_WR_04H :in std_logic;
                CONF_DATA_04H :out std_logic_vector(31 downto 0)
        );
end entity CONFIG_04H;

architecture CONFIG_04H_DESIGN of CONFIG_04H is

        signal CONF_STATUS :std_logic_vector(31 downto 16);
        signal CONF_COMMAND :std_logic_vector(15 downto 0);

begin

 --*******************************************************************
 --************* PCI Configuration Space Header "STATUS" *************
 --*******************************************************************

        CONF_STATUS(20 downto 16) <= "00000";-- Reserved
        CONF_STATUS(21 ) <= '0';-- MAS/TAR: "R_O" :'0'= 33MHz / '1'= 66MHz
        CONF_STATUS(22 ) <= '0';-- MAS/TAR: "R_O"
        CONF_STATUS(23 ) <= '0';-- ???/???: "R_O" : fast back-to-back
        CONF_STATUS(24 ) <= '0';-- Master :
        --CONF_STATUS(26 downto 25) <= "00";-- Mas/Tar: "R_O" : timing fast for "DEVSEL"
        CONF_STATUS(26 downto 25) <= "01";-- Mas/Tar: "R_O" : timing medium for "DEVSEL"
        --CONF_STATUS(26 downto 25) <= "10";-- Mas/Tar: "R_O" : timing slow for "DEVSEL"
        --CONF_STATUS(26 downto 25) <= "11";-- Mas/Tar: "R_O" : reserved
        CONF_STATUS(27 ) <= '0';-- Target : "R_W" : Taget-Abort
        CONF_STATUS(28 ) <= '0';-- Master : "R_W" : Taget-Abort
        CONF_STATUS(29 ) <= '0';-- Master : "R_W" : Master-Abort
        --CONF_STATUS(30 ) <= SERR;-- Mas/Tar: "R_W" : SERR
        --CONF_STATUS(31 ) <= PERR;-- Mas/Tar: "R_W" : PERR

        process (PCI_CLOCK,PCI_RSTn)
        begin
        if PCI_RSTn = '0' then
                CONF_STATUS(30) <= '0';
                CONF_STATUS(31) <= '0';

        elsif (rising_edge(PCI_CLOCK)) then
                if CONF_WR_04H = '1' and CBE_REGn(3) = '0' then
                        CONF_STATUS(30) <= not (AD_REG(30) and CONF_STATUS(30));
                        CONF_STATUS(31) <= not (AD_REG(31) and CONF_STATUS(31));

                else
                        CONF_STATUS(30) <= SERR or CONF_STATUS(30);
                        CONF_STATUS(31) <= PERR or CONF_STATUS(31);

                end if;
        end if;
end process;

 --*******************************************************************
 --*********** PCI Configuration Space Header "COMMAND" **************
 --*******************************************************************

-- CONF_COMMAND( 0) <= '0';-- I/O Space accesses ???
-- CONF_COMMAND( 1) <= '0';-- Mem Space accesses ???
-- CONF_COMMAND( 2) <= '0';-- abillity to act as a master on the PCI bus
-- CONF_COMMAND( 3) <= '0';-- Special Cycle ???
-- CONF_COMMAND( 4) <= '0';-- Master ???
-- CONF_COMMAND( 5) <= '0';-- VGA ???
-- CONF_COMMAND( 6) <= '0';-- Party checking enable/disable
CONF_COMMAND( 7) <= '0';-- address/data stepping ???
-- CONF_COMMAND( 8) <= '0';-- enable/disable "PCI_SERRn"
-- CONF_COMMAND( 9) <= '0';-- fast back-to-back
-- CONF_COMMAND(10) <= '0';-- Reserved
-- CONF_COMMAND(11) <= '0';-- Reserved
-- CONF_COMMAND(12) <= '0';-- Reserved
-- CONF_COMMAND(13) <= '0';-- Reserved
-- CONF_COMMAND(14) <= '0';-- Reserved
-- CONF_COMMAND(15) <= '0';-- Reserved

process (PCI_CLOCK,PCI_RSTn)
begin
        if PCI_RSTn = '0' then
                CONF_COMMAND(15 downto 8) <= (others =>'0');
                CONF_COMMAND( 6 downto 0) <= (others =>'0');

        elsif (rising_edge(PCI_CLOCK)) then

                if CONF_WR_04H = '1'and CBE_REGn(1) = '0' then
                        CONF_COMMAND(15 downto 8) <= AD_REG(15 downto 8);
                else
                        CONF_COMMAND(15 downto 8) <= CONF_COMMAND(15 downto 8);
                end if;

                if CONF_WR_04H = '1'and CBE_REGn(0) = '0' then
                        CONF_COMMAND( 6 downto 0) <= AD_REG( 6 downto 0);
                else
                        CONF_COMMAND( 6 downto 0) <= CONF_COMMAND( 6 downto 0);
                end if;
        end if;
end process;

CONF_DATA_04H <= CONF_STATUS & CONF_COMMAND;

end architecture CONFIG_04H_DESIGN;