OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [or1200/] [rtl/] [verilog/] [or1200_dmmu_top.v] - Blame information for rev 797

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 10 unneback
//////////////////////////////////////////////////////////////////////
2
////                                                              ////
3
////  OR1200's Data MMU top level                                 ////
4
////                                                              ////
5
////  This file is part of the OpenRISC 1200 project              ////
6 258 julius
////  http://www.opencores.org/project,or1k                       ////
7 10 unneback
////                                                              ////
8
////  Description                                                 ////
9
////  Instantiation of all DMMU blocks.                           ////
10
////                                                              ////
11
////  To Do:                                                      ////
12
////   - make it smaller and faster                               ////
13
////                                                              ////
14
////  Author(s):                                                  ////
15
////      - Damjan Lampret, lampret@opencores.org                 ////
16
////                                                              ////
17
//////////////////////////////////////////////////////////////////////
18
////                                                              ////
19
//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////
20
////                                                              ////
21
//// This source file may be used and distributed without         ////
22
//// restriction provided that this copyright statement is not    ////
23
//// removed from the file and that any derivative work contains  ////
24
//// the original copyright notice and the associated disclaimer. ////
25
////                                                              ////
26
//// This source file is free software; you can redistribute it   ////
27
//// and/or modify it under the terms of the GNU Lesser General   ////
28
//// Public License as published by the Free Software Foundation; ////
29
//// either version 2.1 of the License, or (at your option) any   ////
30
//// later version.                                               ////
31
////                                                              ////
32
//// This source is distributed in the hope that it will be       ////
33
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
34
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
35
//// PURPOSE.  See the GNU Lesser General Public License for more ////
36
//// details.                                                     ////
37
////                                                              ////
38
//// You should have received a copy of the GNU Lesser General    ////
39
//// Public License along with this source; if not, download it   ////
40
//// from http://www.opencores.org/lgpl.shtml                     ////
41
////                                                              ////
42
//////////////////////////////////////////////////////////////////////
43
//
44 141 marcus.erl
// $Log: or1200_dmmu_top.v,v $
45
// Revision 2.0  2010/06/30 11:00:00  ORSoC
46
// Minor update: 
47
// Bugs fixed. 
48
//
49 10 unneback
 
50
// synopsys translate_off
51
`include "timescale.v"
52
// synopsys translate_on
53
`include "or1200_defines.v"
54
 
55
//
56
// Data MMU
57
//
58
 
59
module or1200_dmmu_top(
60
        // Rst and clk
61
        clk, rst,
62
 
63
        // CPU i/f
64
        dc_en, dmmu_en, supv, dcpu_adr_i, dcpu_cycstb_i, dcpu_we_i,
65
        dcpu_tag_o, dcpu_err_o,
66
 
67
        // SPR access
68
        spr_cs, spr_write, spr_addr, spr_dat_i, spr_dat_o,
69
 
70
`ifdef OR1200_BIST
71
        // RAM BIST
72
        mbist_si_i, mbist_so_o, mbist_ctrl_i,
73
`endif
74
 
75
        // DC i/f
76
        qmemdmmu_err_i, qmemdmmu_tag_i, qmemdmmu_adr_o, qmemdmmu_cycstb_o, qmemdmmu_ci_o
77
);
78
 
79
parameter dw = `OR1200_OPERAND_WIDTH;
80
parameter aw = `OR1200_OPERAND_WIDTH;
81
 
82
//
83
// I/O
84
//
85
 
86
//
87
// Clock and reset
88
//
89
input                           clk;
90
input                           rst;
91
 
92
//
93
// CPU I/F
94
//
95
input                           dc_en;
96
input                           dmmu_en;
97
input                           supv;
98
input   [aw-1:0]         dcpu_adr_i;
99
input                           dcpu_cycstb_i;
100
input                           dcpu_we_i;
101
output  [3:0]                    dcpu_tag_o;
102
output                          dcpu_err_o;
103
 
104
//
105
// SPR access
106
//
107
input                           spr_cs;
108
input                           spr_write;
109
input   [aw-1:0]         spr_addr;
110
input   [31:0]                   spr_dat_i;
111
output  [31:0]                   spr_dat_o;
112
 
113
`ifdef OR1200_BIST
114
//
115
// RAM BIST
116
//
117
input mbist_si_i;
118
input [`OR1200_MBIST_CTRL_WIDTH - 1:0] mbist_ctrl_i;
119
output mbist_so_o;
120
`endif
121
 
122
//
123
// DC I/F
124
//
125
input                           qmemdmmu_err_i;
126
input   [3:0]                    qmemdmmu_tag_i;
127
output  [aw-1:0]         qmemdmmu_adr_o;
128
output                          qmemdmmu_cycstb_o;
129
output                          qmemdmmu_ci_o;
130
 
131
//
132
// Internal wires and regs
133
//
134
wire                            dtlb_spr_access;
135
wire    [31:`OR1200_DMMU_PS]    dtlb_ppn;
136
wire                            dtlb_hit;
137
wire                            dtlb_uwe;
138
wire                            dtlb_ure;
139
wire                            dtlb_swe;
140
wire                            dtlb_sre;
141
wire    [31:0]                   dtlb_dat_o;
142
wire                            dtlb_en;
143
wire                            dtlb_ci;
144
wire                            fault;
145
wire                            miss;
146
`ifdef OR1200_NO_DMMU
147
`else
148
reg                             dtlb_done;
149
reg     [31:`OR1200_DMMU_PS]    dcpu_vpn_r;
150
`endif
151
 
152
//
153
// Implemented bits inside match and translate registers
154
//
155
// dtlbwYmrX: vpn 31-10  v 0
156
// dtlbwYtrX: ppn 31-10  swe 9  sre 8  uwe 7  ure 6
157
//
158
// dtlb memory width:
159
// 19 bits for ppn
160
// 13 bits for vpn
161
// 1 bit for valid
162
// 4 bits for protection
163
// 1 bit for cache inhibit
164
 
165
`ifdef OR1200_NO_DMMU
166
 
167
//
168
// Put all outputs in inactive state
169
//
170
assign spr_dat_o = 32'h00000000;
171
assign qmemdmmu_adr_o = dcpu_adr_i;
172
assign dcpu_tag_o = qmemdmmu_tag_i;
173
assign qmemdmmu_cycstb_o = dcpu_cycstb_i;
174
assign dcpu_err_o = qmemdmmu_err_i;
175
assign qmemdmmu_ci_o = `OR1200_DMMU_CI;
176
`ifdef OR1200_BIST
177
assign mbist_so_o = mbist_si_i;
178
`endif
179
 
180
`else
181
 
182
//
183
// DTLB SPR access
184
//
185
// 0A00 - 0AFF  dtlbmr w0
186
// 0A00 - 0A3F  dtlbmr w0 [63:0]
187
//
188
// 0B00 - 0BFF  dtlbtr w0
189
// 0B00 - 0B3F  dtlbtr w0 [63:0]
190
//
191
assign dtlb_spr_access = spr_cs;
192
 
193
//
194
// Tags:
195
//
196
// OR1200_DTAG_TE - TLB miss Exception
197
// OR1200_DTAG_PE - Page fault Exception
198
//
199
assign dcpu_tag_o = miss ? `OR1200_DTAG_TE : fault ? `OR1200_DTAG_PE : qmemdmmu_tag_i;
200
 
201
//
202
// dcpu_err_o
203
//
204
assign dcpu_err_o = miss | fault | qmemdmmu_err_i;
205
 
206
//
207 258 julius
// Assert dtlb_done one clock cycle after new address and dtlb_en must be active
208 10 unneback
//
209 358 julius
always @(posedge clk or `OR1200_RST_EVENT rst)
210
        if (rst == `OR1200_RST_VALUE)
211 258 julius
                dtlb_done <=  1'b0;
212 10 unneback
        else if (dtlb_en)
213 258 julius
                dtlb_done <=  dcpu_cycstb_i;
214 10 unneback
        else
215 258 julius
                dtlb_done <=  1'b0;
216 10 unneback
 
217
//
218 258 julius
// Cut transfer if something goes wrong with translation. Also delayed signals 
219
// because of translation delay.
220
assign qmemdmmu_cycstb_o = (dc_en & dmmu_en) ?
221
                           !(miss | fault) & dtlb_done & dcpu_cycstb_i :
222
                           !(miss | fault) & dcpu_cycstb_i;
223 10 unneback
 
224 258 julius
 
225 10 unneback
//
226
// Cache Inhibit
227
//
228 141 marcus.erl
assign qmemdmmu_ci_o = dmmu_en ? dtlb_ci : `OR1200_DMMU_CI;
229 10 unneback
 
230
//
231 258 julius
// Register dcpu_adr_i's VPN for use when DMMU is not enabled but PPN is 
232
// expected to come one clock cycle after offset part.
233 10 unneback
//
234 358 julius
always @(posedge clk or `OR1200_RST_EVENT rst)
235
        if (rst == `OR1200_RST_VALUE)
236 364 julius
                dcpu_vpn_r <=  {32-`OR1200_DMMU_PS{1'b0}};
237 10 unneback
        else
238 258 julius
                dcpu_vpn_r <=  dcpu_adr_i[31:`OR1200_DMMU_PS];
239 10 unneback
 
240
//
241
// Physical address is either translated virtual address or
242
// simply equal when DMMU is disabled
243
//
244 258 julius
assign qmemdmmu_adr_o = dmmu_en ? {dtlb_ppn, dcpu_adr_i[`OR1200_DMMU_PS-1:0]} :
245
                                  dcpu_adr_i;
246 10 unneback
 
247
//
248
// Output to SPRS unit
249
//
250
assign spr_dat_o = dtlb_spr_access ? dtlb_dat_o : 32'h00000000;
251
 
252
//
253
// Page fault exception logic
254
//
255
assign fault = dtlb_done &
256 258 julius
        (  (!dcpu_we_i & !supv & !dtlb_ure) // Load in user mode not enabled
257
           || (!dcpu_we_i & supv & !dtlb_sre) // Load in supv mode not enabled
258
           || (dcpu_we_i & !supv & !dtlb_uwe) // Store in user mode not enabled
259
           || (dcpu_we_i & supv & !dtlb_swe)); // Store in supv mode not enabled
260 10 unneback
 
261
//
262
// TLB Miss exception logic
263
//
264
assign miss = dtlb_done & !dtlb_hit;
265
 
266
//
267
// DTLB Enable
268
//
269
assign dtlb_en = dmmu_en & dcpu_cycstb_i;
270
 
271
//
272
// Instantiation of DTLB
273
//
274
or1200_dmmu_tlb or1200_dmmu_tlb(
275
        // Rst and clk
276
        .clk(clk),
277
        .rst(rst),
278
 
279
        // I/F for translation
280
        .tlb_en(dtlb_en),
281
        .vaddr(dcpu_adr_i),
282
        .hit(dtlb_hit),
283
        .ppn(dtlb_ppn),
284
        .uwe(dtlb_uwe),
285
        .ure(dtlb_ure),
286
        .swe(dtlb_swe),
287
        .sre(dtlb_sre),
288
        .ci(dtlb_ci),
289
 
290
`ifdef OR1200_BIST
291
        // RAM BIST
292
        .mbist_si_i(mbist_si_i),
293
        .mbist_so_o(mbist_so_o),
294
        .mbist_ctrl_i(mbist_ctrl_i),
295
`endif
296
 
297
        // SPR access
298
        .spr_cs(dtlb_spr_access),
299
        .spr_write(spr_write),
300
        .spr_addr(spr_addr),
301
        .spr_dat_i(spr_dat_i),
302
        .spr_dat_o(dtlb_dat_o)
303
);
304
 
305
`endif
306
 
307
endmodule

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.