+= read registers from userland

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

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

library ieee;
use ieee.std_logic_1164.all;

entity CONT_FSM is
        port
        (
                PCI_CLOCK :in std_logic;
                PCI_RSTn :in std_logic;
                IO_READ :in std_logic;
                IO_WRITE :in std_logic;
                CONF_READ :in std_logic;
                CONF_WRITE :in std_logic;
                FIFO_READ :in std_logic;
                READ :out std_logic;--> MUX_SEL(1) , OE_PCI_AD
                PERR_CHECK :out std_logic;
                DEVSELn :out std_logic;
                OE_PCI_PAR :out std_logic;
                OE_PCI_PERR :out std_logic;
                TRDYn :out std_logic;
                PCI_TRDYn :out std_logic; -- s/t/s
                PCI_STOPn :out std_logic; -- s/t/s
                PCI_DEVSELn :out std_logic; -- s/t/s
                FIFO_RDn :out std_logic
        );
end entity CONT_FSM;

architecture CONT_FSM_DESIGN of CONT_FSM is



 --**********************************************************
 --*** CONTROL FSM CODIERUNG ***
 --**********************************************************
 --
 --
 --
 -- |----------- HELP
 -- ||---------- FIFO_READn
 -- |||--------- OE_PCI_PERR
 -- ||||-------- PERR_CHECK
 -- |||||------- TRDYn
 -- ||||||------ STOPn
 -- |||||||----- DEVSELn
 -- ||||||||---- OE_PCI_PAR
 -- |||||||||--- OE_CONTROL
 -- ||||||||||-- READ / MUX_SEL(1) / OE_PCI_AD
 -- ||||||||||
        constant ST_IDLE :std_logic_vector (9 downto 0) := "0100111000";-- 138

        constant ST_READ_1 :std_logic_vector (9 downto 0) := "0100110011";-- 133
        constant ST_READ_2 :std_logic_vector (9 downto 0) := "0100000111";-- 107
        constant ST_READ_3 :std_logic_vector (9 downto 0) := "0100111111";-- 13F

        constant ST_RD_FIFO_1 :std_logic_vector (9 downto 0) := "0000110011";-- 033
        constant ST_RD_FIFO_2 :std_logic_vector (9 downto 0) := "1100110011";-- 233


        constant ST_WRITE_1 :std_logic_vector (9 downto 0) := "0111110010";-- 1F2
        constant ST_WRITE_2 :std_logic_vector (9 downto 0) := "0110000010";-- 182
        constant ST_WRITE_3 :std_logic_vector (9 downto 0) := "0110111010";-- 1BA

        signal CONTROL_STATE :std_logic_vector (9 downto 0);


 --signal DEVSELn :std_logic;
        signal STOPn :std_logic;
 --signal TRDYn :std_logic;

 --************************************************************
 --*** FSM SPEICHER-AUTOMAT ***
 --************************************************************

        attribute syn_state_machine : boolean;
        attribute syn_state_machine of CONTROL_STATE : signal is false;

begin

 --**********************************************************
 --*** CONTROL FSM ***
 --**********************************************************

        process (PCI_CLOCK, PCI_RSTn)
        begin
                if PCI_RSTn = '0' then CONTROL_STATE <= ST_IDLE;

        elsif (rising_edge(PCI_CLOCK)) then

                case CONTROL_STATE is
                when ST_IDLE =>
                        if IO_READ = '1' then
                                CONTROL_STATE <= ST_READ_1;

                        elsif CONF_READ = '1' then
                                CONTROL_STATE <= ST_READ_1;

                        elsif IO_WRITE = '1' then
                                CONTROL_STATE <= ST_WRITE_1;

                        elsif CONF_WRITE = '1' then
                                CONTROL_STATE <= ST_WRITE_1;

                        else CONTROL_STATE <= ST_IDLE;
                        end if;

                -- when ST_READ_1 =>
                -- CONTROL_STATE <= ST_READ_2;

                when ST_READ_1 =>
                        if FIFO_READ = '1' then
                                CONTROL_STATE <= ST_RD_FIFO_1;
                        else
                                CONTROL_STATE <= ST_READ_2;
                        end if;

                when ST_READ_2 =>
                        CONTROL_STATE <= ST_READ_3;

                when ST_READ_3 =>
                        CONTROL_STATE <= ST_IDLE;

                when ST_RD_FIFO_1=>
                        CONTROL_STATE <= ST_RD_FIFO_2;

                when ST_RD_FIFO_2=>
                        CONTROL_STATE <= ST_READ_2;

                when ST_WRITE_1 =>
                        CONTROL_STATE <= ST_WRITE_2;

                when ST_WRITE_2 =>
                        CONTROL_STATE <= ST_WRITE_3;

                when ST_WRITE_3 =>
                        CONTROL_STATE <= ST_IDLE;

                when others =>
                        CONTROL_STATE <= ST_IDLE;

                end case; -- COMM_STATE
        end if; -- CLOCK
end process; -- PROCESS


READ <= CONTROL_STATE(0);
--OE_CONTROL <= CONTROL_STATE(1);
OE_PCI_PAR <= CONTROL_STATE(2);
DEVSELn <= CONTROL_STATE(3);
STOPn <= CONTROL_STATE(4);
TRDYn <= CONTROL_STATE(5);
PERR_CHECK <= CONTROL_STATE(6);
OE_PCI_PERR <= CONTROL_STATE(7);

FIFO_RDn <= CONTROL_STATE(8);


PCI_DEVSELn <= CONTROL_STATE(3) when CONTROL_STATE(1) = '1' else 'Z';
PCI_STOPn <= STOPn when CONTROL_STATE(1) = '1' else 'Z';
PCI_TRDYn <= CONTROL_STATE(5) when CONTROL_STATE(1) = '1' else 'Z';

end architecture CONT_FSM_DESIGN;