Subversion Repositories mips_enhanced

------------------------------------------------------------------------------

--  This file is a part of the GRLIB VHDL IP LIBRARY

--  Copyright (C) 2003, Gaisler Research

--

--  This program is free software; you can redistribute it and/or modify

--  it under the terms of the GNU General Public License as published by

--  the Free Software Foundation; either version 2 of the License, or

--  (at your option) any later version.

--

--  This program is distributed in the hope that it will be useful,

--  but WITHOUT ANY WARRANTY; without even the implied warranty of

--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

--  GNU General Public License for more details.

--

--  You should have received a copy of the GNU General Public License

--  along with this program; if not, write to the Free Software

--  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 

-----------------------------------------------------------------------------

-- Entity:      ahbtbm

-- File:        ahbtbm.vhd

-- Author:      Nils-Johan Wessman - Gaisler Research

-- Description: AHB Testbench master 

------------------------------------------------------------------------------  

library IEEE;

use IEEE.std_logic_1164.all;

library grlib;

use grlib.amba.all;

use grlib.stdlib.all;

use grlib.devices.all;

library gaisler;

use gaisler.misc.all;

use work.ahbtbp.all;

entity ahbtbm is

  generic (

    hindex  : integer := 0;

    hirq    : integer := 0;

    venid   : integer := VENDOR_GAISLER;

    devid   : integer := 0;

    version : integer := 0;

    chprot  : integer := 3;

    incaddr : integer := 0);

  port (

    rst   : in  std_ulogic;

    clk   : in  std_ulogic;

    ctrli : in  ahbtbm_ctrl_in_type;

    ctrlo : out ahbtbm_ctrl_out_type;

    ahbmi : in  ahb_mst_in_type;

    ahbmo : out ahb_mst_out_type

    );

end;

architecture rtl of ahbtbm is

constant hconfig : ahb_config_type := (

  others => zero32);

type reg_type is record

  -- new /*

  grant     : std_logic;

  grant2    : std_logic;

  retry     : std_logic_vector(1 downto 0);

  read      : std_logic; -- indicate 

  dbgl      : integer;

  ac        : ahbtbm_access_array_type;

  retryac   : ahbtbm_access_type;

  curac     : ahbtbm_access_type;

  haddr     : std_logic_vector(31 downto 0); -- addr current access

  hdata     : std_logic_vector(31 downto 0); -- data currnet access

  hwrite    : std_logic;                     -- write current access

  hrdata    : std_logic_vector(31 downto 0);

  status    : ahbtbm_status_type;

  dvalid    : std_logic;

  oldhtrans : std_logic_vector(1 downto 0);

  -- new */

  start   : std_ulogic;

  active  : std_ulogic;

end record;

signal dmai : ahb_dma_in_type;

signal dmao : ahb_dma_out_type;

signal r, rin : reg_type;

begin

  ctrlo.rst <= rst;

  ctrlo.clk <= clk;

  comb : process(ahbmi, ctrli, rst, r)

  -- new /*

  variable v       : reg_type;

  variable update  : std_logic;

  variable hbusreq : std_ulogic;   -- bus request

  variable kblimit : std_logic; -- 1 kB limit indicator

  -- new */

  variable ready   : std_ulogic;

  variable retry   : std_ulogic;

  variable mexc    : std_ulogic;

  variable inc     : std_logic_vector(3 downto 0);    -- address increment

  variable haddr   : std_logic_vector(31 downto 0);   -- AHB address

  variable hwdata  : std_logic_vector(31 downto 0);   -- AHB write data

  variable htrans  : std_logic_vector(1 downto 0);    -- transfer type

  variable hwrite  : std_ulogic;                      -- read/write

  variable hburst  : std_logic_vector(2 downto 0);    -- burst type

  variable newaddr : std_logic_vector(10 downto 0); -- next sequential address

  variable hprot   : std_logic_vector(3 downto 0);    -- transfer type

  variable xhirq    : std_logic_vector(NAHBIRQ-1 downto 0);

  begin

    -- new /*

    v := r; update := '0'; hbusreq := '0';--v.retry := '0';

    v.dvalid := '0'; xhirq := (others => '0');

    v.hrdata := ahbmi.hrdata;

    -- pragma translate_off

    if ahbmi.hready = '1' and ahbmi.hresp = HRESP_ERROR then

      v.hrdata := (others => 'X');

    end if;

    -- pragma translate_on

    v.status.err := '0';

    --v.oldhtrans := r.ac(1).htrans;

    kblimit := '0';

    -- Sample grant when hready

    if ahbmi.hready = '1' then

      v.grant := ahbmi.hgrant(hindex);

      v.grant2 := r.grant;

      v.oldhtrans := r.ac(1).htrans;

    end if;

    -- 1k limit

    if (r.ac(0).htrans = HTRANS_SEQ

        and (r.ac(0).haddr(10) xor r.ac(1).haddr(10)) = '1')

       or (r.retryac.htrans = HTRANS_SEQ

        and (r.retryac.haddr(10) xor r.ac(1).haddr(10)) = '1' and r.retry = "10") then

      kblimit := '1';

    end if;

    -- Read in new access

    --if ((ahbmi.hready = '1' and ahbmi.hresp = HRESP_OKAY and r.grant = '1') 

    --  or r.ac(1).htrans = HTRANS_IDLE) and r.retry = '0' then

    --if ahbmi.hready = '1' and ((ahbmi.hresp = HRESP_OKAY and r.grant = '1') 

    --   or r.ac(1).htrans = HTRANS_IDLE) and r.retry = "00" then

    if ahbmi.hready = '1' and (( r.grant = '1' and

       (ahbmi.hresp = HRESP_OKAY or ahbmi.hresp = HRESP_ERROR))

       or r.ac(1).htrans = HTRANS_IDLE) and r.retry = "00" then

        v.ac(1) := r.ac(0); v.ac(0) := ctrli.ac;

        v.curac := r.ac(1);

        v.hdata := r.ac(1).hdata; v.haddr := r.ac(1).haddr;

        v.hwrite := r.ac(1).hwrite; v.dbgl := r.ac(1).ctrl.dbgl;

        v.read := (not r.ac(1).hwrite) and r.ac(1).htrans(1);

        update := '1';

        if kblimit = '1' then v.ac(1).htrans := HTRANS_NONSEQ; end if;

    elsif ahbmi.hready = '0' and ahbmi.hresp = HRESP_RETRY and r.grant2 = '1' then

      if r.retry = "00" then

        v.retryac := r.ac(1);

        v.ac(1) := r.curac;

        v.ac(1).htrans := HTRANS_IDLE;

        v.ac(1).hburst := "000";

        v.retry := "01";

      elsif r.retry = "10" then

        v.ac(1) := r.retryac;

        if kblimit = '1' then v.ac(1).htrans := HTRANS_NONSEQ; end if;

      end if;

    elsif r.retry = "01" then

      v.ac(1).htrans := HTRANS_NONSEQ;

      v.ac(1).hburst := r.curac.hburst;

      v.read := '0';

      v.retry := "10";

    elsif ahbmi.hready = '1' and r.grant = '1' and r.retry = "10" then

      v.read := (not r.ac(1).hwrite) and r.ac(1).htrans(1);

      --if ahbmi.hresp = HRESP_OKAY then

      if ahbmi.hresp = HRESP_OKAY or ahbmi.hresp = HRESP_ERROR then

        v.ac(1) := r.retryac;

        if kblimit = '1' then v.ac(1).htrans := HTRANS_NONSEQ; end if;

        v.retry := "00";

      end if;

    end if;

    -- NONSEQ in retry

    --if r.retry = '1' then v.ac(1).htrans := HTRANS_NONSEQ; end if;

    -- NONSEQ if burst is interrupted

    if r.grant = '0' and r.ac(1).htrans = HTRANS_SEQ then

      v.ac(1).htrans := HTRANS_NONSEQ;

    end if;

    --if r.ac(1).htrans /= HTRANS_IDLE or r.ac(0).htrans /= HTRANS_IDLE then

    --  hbusreq := '1';

    --end if;

    if r.ac(1).htrans = HTRANS_NONSEQ

      or (r.ac(1).htrans = HTRANS_SEQ

          and r.ac(0).htrans /= HTRANS_NONSEQ and kblimit = '0') then

      hbusreq := '1';

    end if;

    --if r.grant = '0' then -- fix dvalid if grant deasserted *** ???

    if r.grant = '0' and ahbmi.hready = '1' then

      v.read := '0';

    end if;

    -- Check read data

    if r.read = '1' and ahbmi.hresp = HRESP_OKAY and ahbmi.hready = '1' then

      v.dvalid := '1';

      if r.hdata /= ahbmi.hrdata then

        v.status.err := '1';

      end if;

    elsif r.read = '1' and ahbmi.hresp = HRESP_ERROR and ahbmi.hready = '1' then

      v.status.err := '1';

    end if;

    -- new */

    if rst = '0' then

      v.ac(0).htrans := (others => '0');

      v.ac(1).htrans := (others => '0');

      v.retry := (others => '0');

      v.read := '0';

      v.ac(1).haddr := (others => '0');

      v.ac(1).htrans := (others => '0');

      v.ac(1).hwrite := '0';

      v.ac(1).hsize := (others => '0');

      v.ac(1).hburst := (others =>'0');

    end if;

    rin <= v;

    ctrlo.update <= update;

    ctrlo.status <= r.status;

    ctrlo.hrdata <= r.hrdata;

    ctrlo.dvalid <= r.dvalid;

    ahbmo.haddr   <= r.ac(1).haddr;

    ahbmo.htrans  <= r.ac(1).htrans;

    ahbmo.hbusreq <= hbusreq;

    ahbmo.hwdata  <= r.hdata;

    ahbmo.hconfig <= hconfig;

    ahbmo.hlock   <= '0';

    ahbmo.hwrite  <= r.ac(1).hwrite;

    ahbmo.hsize   <= r.ac(1).hsize;

    ahbmo.hburst  <= r.ac(1).hburst;

    ahbmo.hprot   <= hprot;

    ahbmo.hirq    <= xhirq;

    ahbmo.hindex  <= hindex;

  end process;

  regs : process(clk)

  begin

    if rising_edge(clk) then

      r <= rin;

-- pragma translate_off

    if r.read = '1' and ahbmi.hready = '1' then --and r.oldhtrans /= HTRANS_IDLE then

      if ahbmi.hresp = HRESP_OKAY then

        if rin.status.err = '0' then

          if r.dbgl >= 2 then

            print(ptime & "Read[" & tost(r.haddr) & "]: " & tost(ahbmi.hrdata));

          end if;

        else

          if r.dbgl >= 1 then

            print(ptime & "Read[" & tost(r.haddr) & "]: " & tost(ahbmi.hrdata)

                  & " != " & tost(r.hdata));

          end if;

        end if;

      elsif ahbmi.hresp = HRESP_RETRY then

          if r.dbgl >= 3 then

            print(ptime & "Read[" & tost(r.haddr) & "]: [RETRY]");

          end if;

      elsif ahbmi.hresp = HRESP_ERROR then

          if r.dbgl >= 1 then

            print(ptime & "Read[" & tost(r.haddr) & "]: [ERROR]");

          end if;

      end if;

    end if;

    if r.hwrite = '1' and ahbmi.hready = '1' and r.oldhtrans /= HTRANS_IDLE then

      if ahbmi.hresp = HRESP_OKAY then

        if r.dbgl >= 2 then

          print(ptime & "Write[" & tost(r.haddr) & "]: " & tost(r.hdata));

        end if;

      elsif ahbmi.hresp = HRESP_RETRY then

        if r.dbgl >= 3 then

          print(ptime & "Write[" & tost(r.haddr) & "]: " & tost(r.hdata)

                & " [RETRY]");

        end if;

      elsif ahbmi.hresp = HRESP_ERROR then

        if r.dbgl >= 1 then

          print(ptime & "Write[" & tost(r.haddr) & "]: " & tost(r.hdata)

                & " [ERROR]");

        end if;

      end if;

    end if;

-- pragma translate_on

    end if;

  end process;

end;