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[/] [w11/] [tags/] [w11a_V0.74/] [rtl/] [ibus/] [ibdr_lp11.vhd] - Rev 38
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-- $Id: ibdr_lp11.vhd 641 2015-02-01 22:12:15Z mueller $ -- -- Copyright 2009-2013 by Walter F.J. Mueller <W.F.J.Mueller@gsi.de> -- -- This program is free software; you may redistribute and/or modify it under -- the terms of the GNU General Public License as published by the Free -- Software Foundation, either version 2, 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 complete details. -- ------------------------------------------------------------------------------ -- Module Name: ibdr_lp11 - syn -- Description: ibus dev(rem): LP11 -- -- Dependencies: - -- Test bench: - -- Target Devices: generic -- Tool versions: ise 8.2-14.7; viv 2014.4; ghdl 0.18-0.31 -- -- Synthesized (xst): -- Date Rev ise Target flop lutl lutm slic t peri -- 2010-10-17 333 12.1 M53d xc3s1000-4 12 35 0 24 s 5.6 -- 2009-07-11 232 10.1.03 K39 xc3s1000-4 11 30 0 19 s 5.8 -- -- Revision History: -- Date Rev Version Comment -- 2013-05-04 515 1.3 BUGFIX: r.err was cleared in racc read ! -- 2011-11-18 427 1.2.2 now numeric_std clean -- 2010-10-23 335 1.2.1 rename RRI_LAM->RB_LAM; -- 2010-10-17 333 1.2 use ibus V2 interface -- 2010-06-11 303 1.1 use IB_MREQ.racc instead of RRI_REQ -- 2009-06-21 228 1.0.1 generate interrupt locally when err=1 -- 2009-05-30 220 1.0 Initial version ------------------------------------------------------------------------------ -- -- Notes: -- - the ERR bit is just a status flag -- - no hardware interlock (DONE forced 0 when ERR=1), like in simh -- - also no interrupt when ERR goes 1, like in simh library ieee; use ieee.std_logic_1164.all; use ieee.numeric_std.all; use work.slvtypes.all; use work.iblib.all; -- ---------------------------------------------------------------------------- entity ibdr_lp11 is -- ibus dev(rem): LP11 -- fixed address: 177514 port ( CLK : in slbit; -- clock RESET : in slbit; -- system reset BRESET : in slbit; -- ibus reset RB_LAM : out slbit; -- remote attention IB_MREQ : in ib_mreq_type; -- ibus request IB_SRES : out ib_sres_type; -- ibus response EI_REQ : out slbit; -- interrupt request EI_ACK : in slbit -- interrupt acknowledge ); end ibdr_lp11; architecture syn of ibdr_lp11 is constant ibaddr_lp11 : slv16 := slv(to_unsigned(8#177514#,16)); constant ibaddr_csr : slv1 := "0"; -- csr address offset constant ibaddr_buf : slv1 := "1"; -- buf address offset constant csr_ibf_err : integer := 15; constant csr_ibf_done : integer := 7; constant csr_ibf_ie : integer := 6; constant buf_ibf_val : integer := 8; type regs_type is record -- state registers ibsel : slbit; -- ibus select err : slbit; -- csr: error flag done : slbit; -- csr: done flag ie : slbit; -- csr: interrupt enable buf : slv7; -- buf: intreq : slbit; -- interrupt request end record regs_type; constant regs_init : regs_type := ( '0', -- ibsel '1', -- err !! is set !! '1', -- done !! is set !! '0', -- ie (others=>'0'), -- buf '0' -- intreq ); signal R_REGS : regs_type := regs_init; signal N_REGS : regs_type := regs_init; begin proc_regs: process (CLK) begin if rising_edge(CLK) then if BRESET = '1' then -- BRESET is 1 for system and ibus reset R_REGS <= regs_init; if RESET = '0' then -- if RESET=0 we do just an ibus reset R_REGS.err <= N_REGS.err; -- don't reset ERR flag end if; else R_REGS <= N_REGS; end if; end if; end process proc_regs; proc_next : process (R_REGS, IB_MREQ, EI_ACK) variable r : regs_type := regs_init; variable n : regs_type := regs_init; variable idout : slv16 := (others=>'0'); variable ibreq : slbit := '0'; variable ibrd : slbit := '0'; variable ibw0 : slbit := '0'; variable ibw1 : slbit := '0'; variable ilam : slbit := '0'; begin r := R_REGS; n := R_REGS; idout := (others=>'0'); ibreq := IB_MREQ.re or IB_MREQ.we; ibrd := IB_MREQ.re; ibw0 := IB_MREQ.we and IB_MREQ.be0; ibw1 := IB_MREQ.we and IB_MREQ.be1; ilam := '0'; -- ibus address decoder n.ibsel := '0'; if IB_MREQ.aval='1' and IB_MREQ.addr(12 downto 2)=ibaddr_lp11(12 downto 2) then n.ibsel := '1'; end if; -- ibus transactions if r.ibsel = '1' then case IB_MREQ.addr(1 downto 1) is when ibaddr_csr => -- CSR -- control status ------------- idout(csr_ibf_err) := r.err; idout(csr_ibf_done) := r.done; idout(csr_ibf_ie) := r.ie; if IB_MREQ.racc = '0' then -- cpu if ibw0 = '1' then n.ie := IB_MREQ.din(csr_ibf_ie); if IB_MREQ.din(csr_ibf_ie) = '1' then if r.done='1' and r.ie='0' then -- ie set while done=1 n.intreq := '1'; -- request interrupt end if; else n.intreq := '0'; end if; end if; else -- rri if ibw1 = '1' then n.err := IB_MREQ.din(csr_ibf_err); end if; end if; when ibaddr_buf => -- BUF -- data buffer ---------------- if IB_MREQ.racc = '0' then -- cpu if ibw0 = '1' then n.buf := IB_MREQ.din(n.buf'range); if r.err = '0' then -- if online (handle via rbus) ilam := '1'; -- request attention n.done := '0'; -- clear done n.intreq := '0'; -- clear interrupt else -- if offline (discard locally) n.done := '1'; -- set done if r.ie = '1' then -- if interrupts enabled n.intreq := '1'; -- request interrupt end if; end if; end if; else -- rri idout(r.buf'range) := r.buf; idout(buf_ibf_val) := not r.done; if ibrd = '1' then n.done := '1'; if r.ie = '1' then n.intreq := '1'; end if; end if; end if; when others => null; end case; end if; -- other state changes if EI_ACK = '1' then n.intreq := '0'; end if; N_REGS <= n; IB_SRES.dout <= idout; IB_SRES.ack <= r.ibsel and ibreq; IB_SRES.busy <= '0'; RB_LAM <= ilam; EI_REQ <= r.intreq; end process proc_next; end syn;