dsu.vhd

sparc org, vhdl rtl code

----------------------------------------------------------------------------
--  This file is a part of the LEON VHDL model
--  Copyright (C) 1999  European Space Agency (ESA)
--
--  This library is free software; you can redistribute it and/or
--  modify it under the terms of the GNU Lesser General Public
--  License as published by the Free Software Foundation; either
--  version 2 of the License, or (at your option) any later version.
--
--  See the file COPYING.LGPL for the full details of the license.


-----------------------------------------------------------------------------
-- Entity: 	dsu
-- File:	dsu.vhd
-- Author:	Jiri Gaisler - Gaisler Research
-- Description:	Debug support unit. 
------------------------------------------------------------------------------

library IEEE;
use IEEE.std_logic_1164.all;
use work.leon_target.all;
use work.leon_config.all;
use work.leon_iface.all;
use work.amba.all;
use work.tech_map.all;
use IEEE.std_logic_unsigned."+";
use IEEE.std_logic_unsigned."-";


entity dsu is
  port (
    rst    : in  std_logic;
    clk    : in  clk_type;
    ahbmi  : in  ahb_mst_in_type;
    ahbsi  : in  ahb_slv_in_type;
    ahbso  : out ahb_slv_out_type;
    dsui   : in  dsu_in_type;
    dsuo   : out dsu_out_type;
    dbgi   : in  iu_debug_out_type;
    dbgo   : out iu_debug_in_type;
    irqo   : in  irq_out_type;
    dmi    : out dsumem_in_type;
    dmo    : in  dsumem_out_type
  );
end; 

architecture rtl of dsu is

-- constant dsuconfig : debug_config_type := leon_config_table(cfgindex).debug;

constant TTIMEBITS : integer := 30; -- timer bits

type dsu_config_reg is record
  tenable       : std_logic;	-- trace enable
  tmode         : std_logic;	-- trace delay counter mode
  btrapa        : std_logic;	-- break on any IU trap
  btrape        : std_logic;	-- break on all IU traps but 3,4,5,6,0x11-0x1f
  berror        : std_logic;	-- break on IU error mode
  bwatch        : std_logic;	-- break on IU watchpoint
  bsoft         : std_logic;	-- break on software breakpoint (TA 1)
  bahb          : std_logic;	-- break on AHB watchpoint hit
  btrace        : std_logic;	-- break on trace freeze
  ftimer        : std_logic;	-- freeze timer on break
  rerror        : std_logic;	-- reset error mode
  step          : std_logic;	-- single step
  lresp         : std_logic;	-- link response enable
  dresp         : std_logic;	-- debug response enable
  dbreak        : std_logic;	-- force CPU in debug mode (write-only)
  dcnten        : std_logic;	-- delay counter enable
  delaycnt      : std_logic_vector(TBUFABITS - 1 downto 0); -- delay counter
end record;

type trace_ctrl_reg is record
  aindex  	: std_logic_vector(TBUFABITS - 1 downto 0); -- buffer index
  pindex  	: std_logic_vector(TBUFABITS - 1 downto 0); -- buffer index
  tproc         : std_logic;	-- trace processor enable
  tahb          : std_logic;	-- trace AHB enable
end record;

type trace_break_reg is record
  addr          : std_logic_vector(31 downto 2);
  mask          : std_logic_vector(31 downto 2);
  read          : std_logic;
  write         : std_logic;
  exec          : std_logic;
end record;

type regtype is record
-- AHB signals
  haddr         : std_logic_vector(31 downto 0);
  hwrite        : std_logic;
  htrans	: std_logic_vector(1 downto 0);
  hsize         : std_logic_vector(2 downto 0);
  hburst        : std_logic_vector(2 downto 0);
  hwdata        : std_logic_vector(31 downto 0);
  hmaster       : std_logic_vector(3 downto 0);
  hmastlock     : std_logic;
  hsel          : std_logic;
  hready        : std_logic;
  hready2       : std_logic;
  hready3       : std_logic;
  ahbactive     : std_logic;

  timer     	: std_logic_vector(TTIMEBITS - 1 downto 0); -- timer
  dsubre    	: std_logic_vector(2 downto 0); -- external DSUBRE signal
  dsuen     	: std_logic_vector(2 downto 0); -- external DSUBRE signal
  dsuact        : std_logic;

  dsucfg        : dsu_config_reg;
  tbreg1	: trace_break_reg;
  tbreg2	: trace_break_reg;
  tctrl 	: trace_ctrl_reg;
end record;

signal r, rin : regtype;
constant zero30 : std_logic_vector(29 downto 0) := (others => '0');

begin

  ctrl : process(rst, ahbmi, ahbsi, dsui, irqo, dbgi, r, dmo)
  variable v : regtype;
  variable vpbufi, vabufi : tracebuf_in_type;
  variable regsd : std_logic_vector(31 downto 0);   -- data from registers
  variable pindex, aindex : std_logic_vector(TBUFABITS - 1 downto 0); -- buffer index
  variable denable, ldst_cycle, bphit, bphit2 : std_logic;
  variable bufdata : std_logic_vector(127 downto 0);
  variable pbufo, abufo : tracebuf_out_type;

  begin

    v := r; regsd := (others => '0'); vpbufi.enable := '0'; vabufi.enable := '0'; 
    vpbufi.data := (others => '0'); vabufi.data := (others => '0'); 
    vpbufi.addr := (others => '0'); vabufi.addr := (others => '0'); 
    vpbufi.write := (others => '0'); vabufi.write := (others => '0'); 
    denable := '0'; bphit := '0'; bphit2 := '0';
    v.hready := r.hready2; v.hready2 := r.hready3; v.hready3 := '0'; 
    pbufo := dmo.pbufo; abufo := dmo.abufo;
    bufdata := pbufo.data;
    ldst_cycle := dbgi.wr.inst(31) and dbgi.wr.inst(30); 
    v.dsubre := r.dsubre(1 downto 0) & dsui.dsubre;
    v.dsuen := r.dsuen(1 downto 0) & dsui.dsuen;
    v.dsucfg.dbreak := r.dsucfg.dbreak or 
	(r.dsubre(1) and not r.dsubre(2)) or dbgi.dmode;
    v.dsuact := dbgi.dmode; v.dsucfg.rerror := '0';

-- trace buffer index and delay counters
    if DSUTRACE then
-- pragma translate_off
      if not is_x(r.timer) then
-- pragma translate_on
        if (r.dsucfg.tenable and not dbgi.dmode2) = '1' then 
	  v.timer := r.timer + 1; 
        end if;
-- pragma translate_off
      end if;
-- pragma translate_on
-- pragma translate_off
      if not is_x(r.tctrl.pindex) then
-- pragma translate_on
        pindex := r.tctrl.pindex + 1;
-- pragma translate_off
      end if;
-- pragma translate_on
      if DSUMIXED then
-- pragma translate_off
        if not is_x(r.tctrl.aindex) then
-- pragma translate_on
          aindex := r.tctrl.aindex + 1;
-- pragma translate_off
        end if;
-- pragma translate_on
      end if;
    end if;

-- check for AHB watchpoints
    if (ahbsi.hready and r.ahbactive ) = '1' then
      if ((((r.tbreg1.addr xor r.haddr(31 downto 2)) and r.tbreg1.mask) = zero30) and
         (((r.tbreg1.read and not r.hwrite) or (r.tbreg1.write and r.hwrite)) = '1')) 
        or ((((r.tbreg2.addr xor r.haddr(31 downto 2)) and r.tbreg2.mask) = zero30) and
           (((r.tbreg2.read and not r.hwrite) or (r.tbreg2.write and r.hwrite)) = '1')) 
      then
	bphit := '1';
	if (r.dsucfg.dcnten = '0') and ((r.tctrl.tahb or r.tctrl.tproc) = '1') and
	   (r.dsucfg.delaycnt /= zero30(TBUFABITS-1 downto 0))
        then v.dsucfg.dcnten := '1'; end if;
	if r.dsucfg.bahb = '1' then v.dsucfg.dbreak := '1'; end if;
      end if;
    end if;

-- check for IU trace breakpoints
    if (dbgi.holdn and dbgi.wr.pv and

	 not dbgi.wr.annul) = '1'

    then
      if ((((r.tbreg1.addr xor dbgi.wr.pc(31 downto 2)) and r.tbreg1.mask) = zero30) and
         (r.tbreg1.exec = '1')) 
        or ((((r.tbreg2.addr xor dbgi.wr.pc(31 downto 2)) and r.tbreg2.mask) = zero30) and
           (r.tbreg2.exec = '1')) 
      then
	bphit2 := '1';
	if (r.dsucfg.tenable = '1') and (r.dsucfg.dcnten = '0') and
	     (r.dsucfg.delaycnt /= zero30(TBUFABITS-1 downto 0))
        then v.dsucfg.dcnten := '1'; end if;
	if r.dsucfg.bahb = '1' then v.dsucfg.dbreak := '1'; end if;
      end if;
    end if;

-- generate buffer inputs
    if DSUTRACE then
      vpbufi.write := "0000"; vabufi.write := "0000";
      if r.dsucfg.tenable = '1' then
	vpbufi.addr := '0' & r.tctrl.pindex;
        vabufi.addr := '0' & r.tctrl.aindex;
        vabufi.data(125 downto 96) := r.timer; 
	vpbufi.data(125 downto 96) := r.timer;
        vabufi.data(127) := bphit;
  	vabufi.data(95 downto 92) := irqo.irl;
  	vabufi.data(91 downto 88) := dbgi.psrpil;
  	vabufi.data(87 downto 80) := dbgi.psrtt;
 	vabufi.data(79) := r.hwrite;
  	vabufi.data(78 downto 77) := r.htrans;
  	vabufi.data(76 downto 74) := r.hsize;
  	vabufi.data(73 downto 71) := r.hburst;
  	vabufi.data(70 downto 67) := r.hmaster;
  	vabufi.data(66) := r.hmastlock;
  	vabufi.data(65 downto 64) := ahbmi.hresp;
        if r.hwrite = '1' then
          vabufi.data(63 downto 32) := ahbsi.hwdata;
        else
          vabufi.data(63 downto 32) := ahbmi.hrdata;
        end if; 
        vabufi.data(31 downto 0) := r.haddr;
        vpbufi.data(127) := bphit2;
        vpbufi.data(126) := not dbgi.wr.pv;
        vpbufi.data(95 downto 64) := dbgi.result;
        vpbufi.data(63 downto 32) := dbgi.wr.pc(31 downto 2) & 
			            dbgi.trap & dbgi.error;
        vpbufi.data(31 downto 0) := dbgi.wr.inst;
      else
        vpbufi.addr := '0' & r.haddr(TBUFABITS+3 downto 4);
        vabufi.addr := '1' & r.haddr(TBUFABITS+3 downto 4);
        vpbufi.data := ahbsi.hwdata & ahbsi.hwdata & ahbsi.hwdata & ahbsi.hwdata;
        vabufi.data := vpbufi.data;
      end if;

-- write trace buffer
      if r.dsucfg.tenable = '1' then 
        if (r.tctrl.tahb and r.ahbactive and ahbsi.hready) = '1' then
	  if DSUMIXED then
	    v.tctrl.aindex := aindex;
            vabufi.enable := '1'; vabufi.write := "1111"; 
	  elsif (r.tctrl.tproc = '0') then 
	    v.tctrl.pindex := pindex;
            vpbufi.enable := '1'; vpbufi.write := "1111"; 
	  end if;
        end if;
        if (r.tctrl.tproc and dbgi.holdn and 
	 (dbgi.wr.pv or dbgi.write_reg or ldst_cycle)

	  and (not dbgi.vdmode) and not dbgi.wr.annul) = '1'

        then
          vpbufi.enable := '1'; vpbufi.write := "1111";