identing

[raggedstone] / dhwk / source / config_rd_0.vhd

-- J.STELZNER
-- INFORMATIK-3 LABOR
-- 23.08.2006
-- File: CONFIG_RD_0.VHD

library IEEE;
use IEEE.std_logic_1164.all;

entity CONFIG_RD_0 is
        port
        (
                ADDR_REG :in std_logic_vector (31 downto 0);
                CF_RD_COM :in std_logic;
                READ_SEL :out std_logic_vector ( 2 downto 0)
        );
end entity CONFIG_RD_0;

architecture CONFIG_RD_0_DESIGN of CONFIG_RD_0 is

 --
 --
 --
 --
 --
 -- PCI Configuration Space Header
 --
 -- \ Bit
 -- \
 --Address |31 24|23 16|15 8|7 0|
 -----------------------------------------------------------------
 --00 |Device ID |Vendor ID |
 --04 |Status |Command |
 --08 |Class Code |Revision ID|
 --0C |BIST |Header Type|Latency T. |Cache L.S. |
 --10-24 |Base Address Register |
 --28 |Cardbus CIS Pointer |
 --2C |Subsystem ID |Subsystem Vendor ID |
 --30 |Expansion ROM Base Address |
 --34 |Reserved |
 --38 |Reserved |
 --3C |Max_Lat |Min_Gnt |Int_Pin |Int_Line |
 --40-FF | |
 -----------------------------------------------------------------


 --PCI Bus Commands
 --C/BE[3..0] Command Type
 --------------------------------------
 -- 0000 Interrupt Acknowledge
 -- 0001 Special Cycle
 -- 0010 I/O Read
 -- 0011 I/O Write
 -- 0100 Reserved
 -- 0101 Reserved
 -- 0110 Memory Read
 -- 0111 Memory Write
 --
 -- 1000 Reserved
 -- 1001 Reserved
 -- 1010 Configuration Read
 -- 1011 Configuration Write
 -- 1100 Memory Read Multiple
 -- 1101 Dual Address Cycle
 -- 1110 Memory Read Line
 -- 1111 Memory Write and Invalidate


 --PCI Byte Enable
 --C/BE[3..0] gueltige Datenbits
 -------------------------------
 -- 0000 AD 31..0
 -- 1000 AD 23..0
 -- 1100 AD 15..0
 -- 1110 AD 7..0

        constant CMD_INT_ACK :std_logic_vector(3 downto 0) := "0000";
        constant CMD_SP_CYC :std_logic_vector(3 downto 0) := "0001";
        constant CMD_IO_READ :std_logic_vector(3 downto 0) := "0010";
        constant CMD_IO_WRITE :std_logic_vector(3 downto 0) := "0011";
        constant CMD_RES_4 :std_logic_vector(3 downto 0) := "0100";
        constant CMD_RES_5 :std_logic_vector(3 downto 0) := "0101";
        constant CMD_MEM_READ :std_logic_vector(3 downto 0) := "0110";
        constant CMD_MEM_WRITE :std_logic_vector(3 downto 0) := "0111";
        constant CMD_RES_8 :std_logic_vector(3 downto 0) := "1000";
        constant CMD_RES_9 :std_logic_vector(3 downto 0) := "1001";
        constant CMD_CONF_READ :std_logic_vector(3 downto 0) := "1010";
        constant CMD_CONF_WRITE :std_logic_vector(3 downto 0) := "1011";
        constant CMD_MEM_READ_M :std_logic_vector(3 downto 0) := "1100";
        constant CMD_DU_ADR_CYC :std_logic_vector(3 downto 0) := "1101";
        constant CMD_MEN_READ_L :std_logic_vector(3 downto 0) := "1110";
        constant CMD_MEM_WRITE_I :std_logic_vector(3 downto 0) := "1111";

        signal MUX :std_logic_vector(31 downto 0);
        signal CONFIG_ADDR :std_logic_vector( 7 downto 0);

begin

        CONFIG_ADDR(7 downto 0) <= ADDR_REG(7 downto 0);

 --*******************************************************************
 --*********************** PCI Read Address **************************
 --*******************************************************************

        process (CF_RD_COM, CONFIG_ADDR)
        begin

                if CF_RD_COM = '1' then
                        if CONFIG_ADDR = X"00" then
                                READ_SEL <= "000";

                        elsif CONFIG_ADDR = X"04" then
                                READ_SEL <= "001";

                        elsif CONFIG_ADDR = X"08" then
                                READ_SEL <= "010";

                        elsif CONFIG_ADDR = X"10" then
                                READ_SEL <= "011";

                        elsif CONFIG_ADDR = X"3C" then
                                READ_SEL <= "100";

                        elsif CONFIG_ADDR = X"40" then
                                READ_SEL <= "101";

                        else
                                READ_SEL <= "111";
                        end if;
                else
                        READ_SEL <= "111";
                end if;
        end process;

end architecture CONFIG_RD_0_DESIGN;