1 |
2 |
wfjm |
-- $Id: pdp11_psr.vhd 314 2010-07-09 17:38:41Z mueller $
|
2 |
|
|
--
|
3 |
|
|
-- Copyright 2006-2009 by Walter F.J. Mueller <W.F.J.Mueller@gsi.de>
|
4 |
|
|
--
|
5 |
|
|
-- This program is free software; you may redistribute and/or modify it under
|
6 |
|
|
-- the terms of the GNU General Public License as published by the Free
|
7 |
|
|
-- Software Foundation, either version 2, or at your option any later version.
|
8 |
|
|
--
|
9 |
|
|
-- This program is distributed in the hope that it will be useful, but
|
10 |
|
|
-- WITHOUT ANY WARRANTY, without even the implied warranty of MERCHANTABILITY
|
11 |
|
|
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
12 |
|
|
-- for complete details.
|
13 |
|
|
--
|
14 |
|
|
------------------------------------------------------------------------------
|
15 |
|
|
-- Module Name: pdp11_psr - syn
|
16 |
|
|
-- Description: pdp11: processor status word register
|
17 |
|
|
--
|
18 |
|
|
-- Dependencies: -
|
19 |
|
|
-- Test bench: tb/tb_pdp11_core (implicit)
|
20 |
|
|
-- Target Devices: generic
|
21 |
|
|
-- Tool versions: xst 8.1, 8.2, 9.1, 9.2; ghdl 0.18-0.25
|
22 |
|
|
-- Revision History:
|
23 |
|
|
-- Date Rev Version Comment
|
24 |
|
|
-- 2009-05-30 220 1.1.4 final removal of snoopers (were already commented)
|
25 |
|
|
-- 2008-08-22 161 1.1.3 rename ubf_ -> ibf_; use iblib
|
26 |
|
|
-- 2008-03-02 121 1.1.2 remove snoopers
|
27 |
|
|
-- 2008-01-05 110 1.1.1 rename IB_MREQ(ena->req) SRES(sel->ack, hold->busy)
|
28 |
|
|
-- 2007-12-30 107 1.1 use IB_MREQ/IB_SRES interface now
|
29 |
|
|
-- 2007-06-14 56 1.0.1 Use slvtypes.all
|
30 |
|
|
-- 2007-05-12 26 1.0 Initial version
|
31 |
|
|
------------------------------------------------------------------------------
|
32 |
|
|
|
33 |
|
|
library ieee;
|
34 |
|
|
use ieee.std_logic_1164.all;
|
35 |
|
|
use ieee.std_logic_arith.all;
|
36 |
|
|
|
37 |
|
|
use work.slvtypes.all;
|
38 |
|
|
use work.iblib.all;
|
39 |
|
|
use work.pdp11.all;
|
40 |
|
|
|
41 |
|
|
-- ----------------------------------------------------------------------------
|
42 |
|
|
|
43 |
|
|
entity pdp11_psr is -- processor status word register
|
44 |
|
|
port (
|
45 |
|
|
CLK : in slbit; -- clock
|
46 |
|
|
CRESET : in slbit; -- console reset
|
47 |
|
|
DIN : in slv16; -- input data
|
48 |
|
|
CCIN : in slv4; -- cc input
|
49 |
|
|
CCWE : in slbit; -- enable update cc
|
50 |
|
|
WE : in slbit; -- write enable (from DIN)
|
51 |
|
|
FUNC : in slv3; -- write function (from DIN)
|
52 |
|
|
PSW : out psw_type; -- current psw
|
53 |
|
|
IB_MREQ : in ib_mreq_type; -- ibus request
|
54 |
|
|
IB_SRES : out ib_sres_type -- ibus response
|
55 |
|
|
);
|
56 |
|
|
end pdp11_psr;
|
57 |
|
|
|
58 |
|
|
architecture syn of pdp11_psr is
|
59 |
|
|
|
60 |
|
|
constant ibaddr_psr : slv16 := conv_std_logic_vector(8#177776#,16);
|
61 |
|
|
|
62 |
|
|
signal IBSEL_PSR : slbit := '0';
|
63 |
|
|
signal R_PSW : psw_type := psw_init; -- ps register
|
64 |
|
|
|
65 |
|
|
begin
|
66 |
|
|
|
67 |
|
|
proc_ibsel: process (IB_MREQ)
|
68 |
|
|
variable ipsr : slbit := '0';
|
69 |
|
|
begin
|
70 |
|
|
ipsr := '0';
|
71 |
|
|
if IB_MREQ.req='1' and IB_MREQ.addr=ibaddr_psr(12 downto 1) then
|
72 |
|
|
ipsr := '1';
|
73 |
|
|
end if;
|
74 |
|
|
IBSEL_PSR <= ipsr;
|
75 |
|
|
IB_SRES.ack <= ipsr;
|
76 |
|
|
IB_SRES.busy <= '0';
|
77 |
|
|
end process proc_ibsel;
|
78 |
|
|
|
79 |
|
|
proc_ibdout: process (IBSEL_PSR, R_PSW)
|
80 |
|
|
variable pswout : slv16 := (others=>'0');
|
81 |
|
|
begin
|
82 |
|
|
pswout := (others=>'0');
|
83 |
|
|
if IBSEL_PSR = '1' then
|
84 |
|
|
pswout(psw_ibf_cmode) := R_PSW.cmode;
|
85 |
|
|
pswout(psw_ibf_pmode) := R_PSW.pmode;
|
86 |
|
|
pswout(psw_ibf_rset) := R_PSW.rset;
|
87 |
|
|
pswout(psw_ibf_pri) := R_PSW.pri;
|
88 |
|
|
pswout(psw_ibf_tflag) := R_PSW.tflag;
|
89 |
|
|
pswout(psw_ibf_cc) := R_PSW.cc;
|
90 |
|
|
end if;
|
91 |
|
|
IB_SRES.dout <= pswout;
|
92 |
|
|
end process proc_ibdout;
|
93 |
|
|
|
94 |
|
|
proc_psw : process (CLK)
|
95 |
|
|
begin
|
96 |
|
|
|
97 |
|
|
if CLK'event and CLK='1' then
|
98 |
|
|
|
99 |
|
|
if CRESET = '1' then
|
100 |
|
|
R_PSW <= psw_init;
|
101 |
|
|
|
102 |
|
|
else
|
103 |
|
|
|
104 |
|
|
if CCWE = '1' then
|
105 |
|
|
R_PSW.cc <= CCIN;
|
106 |
|
|
end if;
|
107 |
|
|
|
108 |
|
|
if WE = '1' then
|
109 |
|
|
case FUNC is
|
110 |
|
|
when c_psr_func_wspl => -- wspl
|
111 |
|
|
R_PSW.pri <= DIN(2 downto 0);
|
112 |
|
|
|
113 |
|
|
when c_psr_func_wcc => -- wcc
|
114 |
|
|
if DIN(4) = '1' then -- set cc opcodes
|
115 |
|
|
R_PSW.cc <= R_PSW.cc or DIN(3 downto 0);
|
116 |
|
|
else -- clear cc opcodes
|
117 |
|
|
R_PSW.cc <= R_PSW.cc and not DIN(3 downto 0);
|
118 |
|
|
end if;
|
119 |
|
|
|
120 |
|
|
when c_psr_func_wint => -- wint (interupt handling)
|
121 |
|
|
R_PSW.cmode <= DIN(psw_ibf_cmode);
|
122 |
|
|
R_PSW.pmode <= R_PSW.cmode; -- save current mode
|
123 |
|
|
R_PSW.rset <= DIN(psw_ibf_rset);
|
124 |
|
|
R_PSW.pri <= DIN(psw_ibf_pri);
|
125 |
|
|
R_PSW.tflag <= DIN(psw_ibf_tflag);
|
126 |
|
|
R_PSW.cc <= DIN(psw_ibf_cc);
|
127 |
|
|
|
128 |
|
|
when c_psr_func_wrti => -- wrti (rti/rtt in non-kernel mode)
|
129 |
|
|
R_PSW.cmode <= R_PSW.cmode or DIN(psw_ibf_cmode);
|
130 |
|
|
R_PSW.pmode <= R_PSW.pmode or DIN(psw_ibf_pmode) or
|
131 |
|
|
R_PSW.cmode or DIN(psw_ibf_cmode);
|
132 |
|
|
R_PSW.rset <= R_PSW.rset or DIN(psw_ibf_rset);
|
133 |
|
|
R_PSW.tflag <= DIN(psw_ibf_tflag);
|
134 |
|
|
R_PSW.cc <= DIN(psw_ibf_cc);
|
135 |
|
|
|
136 |
|
|
when c_psr_func_wall => -- wall (rti/rtt kernel mode)
|
137 |
|
|
R_PSW.cmode <= DIN(psw_ibf_cmode);
|
138 |
|
|
R_PSW.pmode <= DIN(psw_ibf_pmode);
|
139 |
|
|
R_PSW.rset <= DIN(psw_ibf_rset);
|
140 |
|
|
R_PSW.pri <= DIN(psw_ibf_pri);
|
141 |
|
|
R_PSW.tflag <= DIN(psw_ibf_tflag);
|
142 |
|
|
R_PSW.cc <= DIN(psw_ibf_cc);
|
143 |
|
|
|
144 |
|
|
when others => null;
|
145 |
|
|
end case;
|
146 |
|
|
end if;
|
147 |
|
|
end if;
|
148 |
|
|
|
149 |
|
|
if IBSEL_PSR='1' and IB_MREQ.we='1' then
|
150 |
|
|
if IB_MREQ.be1 = '1' then
|
151 |
|
|
R_PSW.cmode <= IB_MREQ.din(psw_ibf_cmode);
|
152 |
|
|
R_PSW.pmode <= IB_MREQ.din(psw_ibf_pmode);
|
153 |
|
|
R_PSW.rset <= IB_MREQ.din(psw_ibf_rset);
|
154 |
|
|
end if;
|
155 |
|
|
if IB_MREQ.be0 = '1' then
|
156 |
|
|
R_PSW.pri <= IB_MREQ.din(psw_ibf_pri);
|
157 |
|
|
R_PSW.cc <= IB_MREQ.din(psw_ibf_cc);
|
158 |
|
|
end if;
|
159 |
|
|
end if;
|
160 |
|
|
|
161 |
|
|
end if;
|
162 |
|
|
|
163 |
|
|
end process proc_psw;
|
164 |
|
|
|
165 |
|
|
PSW <= R_PSW;
|
166 |
|
|
|
167 |
|
|
end syn;
|