ReonV/lib/gaisler/can/can_rd.vhd

202 lines
6.6 KiB
VHDL

------------------------------------------------------------------------------
-- This file is a part of the GRLIB VHDL IP LIBRARY
-- Copyright (C) 2003 - 2008, Gaisler Research
-- Copyright (C) 2008 - 2014, Aeroflex Gaisler
-- Copyright (C) 2015 - 2017, Cobham Gaisler
--
-- 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: can_oc
-- File: can_oc.vhd
-- Author: Jiri Gaisler - Gaisler Research
-- Description: AHB interface for the OpenCores CAN MAC
------------------------------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
library grlib;
use grlib.amba.all;
use grlib.stdlib.all;
use grlib.devices.all;
library techmap;
use techmap.gencomp.all;
library gaisler;
use gaisler.can.all;
entity can_rd is
generic (
slvndx : integer := 0;
ioaddr : integer := 16#000#;
iomask : integer := 16#FF0#;
irq : integer := 0;
memtech : integer := DEFMEMTECH;
syncrst : integer := 0;
dmap : integer := 0);
port (
resetn : in std_logic;
clk : in std_logic;
ahbsi : in ahb_slv_in_type;
ahbso : out ahb_slv_out_type;
can_rxi : in std_logic_vector(1 downto 0);
can_txo : out std_logic_vector(1 downto 0)
);
end;
architecture rtl of can_rd is
constant ncores : integer := 1;
constant sepirq : integer := 0;
constant REVISION : amba_version_type := ncores-1;
constant hconfig : ahb_config_type := (
0 => ahb_device_reg ( VENDOR_GAISLER, GAISLER_CANAHB, 0, REVISION, irq),
4 => ahb_iobar(ioaddr, iomask), others => zero32);
type ahbregs is record
hsel : std_ulogic;
hwrite : std_ulogic;
hwrite2 : std_ulogic;
htrans : std_logic_vector(1 downto 0);
haddr : std_logic_vector(10 downto 0);
hwdata : std_logic_vector(7 downto 0);
herr : std_ulogic;
hready : std_ulogic;
ws : std_logic_vector(1 downto 0);
irqi : std_logic_vector(ncores-1 downto 0);
irqo : std_logic_vector(ncores-1 downto 0);
muxsel : std_logic;
writemux : std_logic;
end record;
subtype cdata is std_logic_vector(7 downto 0);
type cdataarr is array (0 to 7) of cdata;
signal data_out : cdataarr;
signal reset : std_logic;
signal irqo : std_logic_vector(ncores-1 downto 0);
signal addr : std_logic_vector(7 downto 0);
signal vcc, gnd : std_ulogic;
signal r, rin : ahbregs;
signal can_lrxi, can_ltxo : std_logic;
begin
gnd <= '0'; vcc <= '1'; reset <= not resetn;
comb : process(ahbsi, r, resetn, data_out, irqo)
variable v : ahbregs;
variable hresp : std_logic_vector(1 downto 0);
variable dataout : std_logic_vector(7 downto 0);
variable irqvec : std_logic_vector(NAHBIRQ-1 downto 0);
variable vmuxreg : std_logic;
variable hwdata : std_logic_vector(31 downto 0);
begin
v := r;
hwdata := ahbreadword(ahbsi.hwdata, r.haddr(4 downto 2));
if (r.hsel = '1' ) and (r.ws /= "11") then v.ws := r.ws + 1; end if;
if ahbsi.hready = '1' then
v.hsel := ahbsi.hsel(slvndx);
v.haddr := ahbsi.haddr(10 downto 0);
v.htrans := ahbsi.htrans;
v.hwrite := ahbsi.hwrite;
v.herr := orv(ahbsi.hsize) and ahbsi.hwrite;
v.ws := "00";
end if;
v.hready := (r.hsel and r.ws(1) and not r.ws(0)) or not resetn
or (ahbsi.hready and not ahbsi.htrans(1));
vmuxreg := not r.haddr(7) and r.haddr(6);
--v.hwrite2 := r.hwrite and r.hsel and r.htrans(1) and r.ws(1)
-- and not r.ws(0) and not r.herr;
v.hwrite2 := r.hwrite and r.hsel and r.htrans(1) and r.ws(1)
and not r.ws(0) and not r.herr and not vmuxreg;
v.writemux := r.hwrite and r.hsel and r.htrans(1) and r.ws(1)
and not r.ws(0) and vmuxreg;
if (r.herr and r.ws(1)) = '1' then hresp := HRESP_ERROR;
else hresp := HRESP_OKAY; end if;
case r.haddr(1 downto 0) is
when "00" => v.hwdata := hwdata(31 downto 24);
when "01" => v.hwdata := hwdata(23 downto 16);
when "10" => v.hwdata := hwdata(15 downto 8);
when others => v.hwdata := hwdata(7 downto 0);
end case;
--dataout := data_out(0);
if r.haddr(7 downto 6) = "01" then
dataout := (others => r.muxsel);
if r.writemux = '1' then
v.muxsel := r.hwdata(0);
end if;
else
dataout := data_out(0);
end if;
-- Interrupt goes to low when appeard and is normal high
-- but the irq controller from leon is active high and the interrupt should appear only
-- for 1 Clk cycle,
v.irqi := irqo; v.irqo:= (r.irqi and not irqo);
irqvec := (others => '0');
if sepirq = 1 then irqvec(ncores-1+irq downto irq) := r.irqo;
else irqvec(irq) := orv(r.irqo); end if;
ahbso.hirq <= irqvec;
ahbso.hrdata <= ahbdrivedata(dataout);
ahbso.hresp <= hresp; rin <= v;
end process;
-- Double mapping of registers [byte (offset 0), word (offset 0x80)]
dmap0 : if dmap = 0 generate
addr <= r.haddr(7 downto 0);
end generate;
dmap1 : if dmap = 1 generate
addr <= "000"&r.haddr(6 downto 2) when r.haddr(7) = '1' else
r.haddr(7 downto 0);
end generate;
reg : process(clk)
begin if clk'event and clk = '1' then r <= rin; end if; end process;
cmod : can_mod generic map (memtech, syncrst)
--port map (reset, clk, r.hsel, r.hwrite2, r.haddr(7 downto 0), r.hwdata,
port map (reset, clk, r.hsel, r.hwrite2, addr, r.hwdata,
data_out(0), irqo(0), can_lrxi, can_ltxo, ahbsi.testen);
cmux : canmux port map (r.muxsel, can_lrxi, can_ltxo, can_rxi, can_txo);
ahbso.hconfig <= hconfig;
ahbso.hindex <= slvndx;
ahbso.hsplit <= (others => '0');
ahbso.hready <= r.hready;
-- pragma translate_off
bootmsg : report_version
generic map (
"can_oc" & tost(slvndx) &
": SJA1000 Compatible CAN MAC, revision " & tost(REVISION) &
", irq " & tost(irq));
-- pragma translate_on
end;