1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
|
--
-- File Name: RandomBasePkg.vhd
-- Design Unit Name: RandomBasePkg
-- Revision: STANDARD VERSION
--
-- Maintainer: Jim Lewis email: jim@synthworks.com
-- Contributor(s):
-- Jim Lewis jim@synthworks.com
--
--
-- Description:
-- Defines Base randomization, seed definition, seed generation,
-- and seed IO functionality for RandomPkg.vhd
-- Defines:
-- Procedure Uniform - baseline randomization
-- Type RandomSeedType - the seed as a single object
-- function GenRandSeed from integer_vector, integer, or string
-- IO function to_string, & procedures write, read
--
-- In revision 2.0 these types and functions are included by package reference.
-- Long term these will be passed as generics to RandomGenericPkg
--
--
-- Developed for:
-- SynthWorks Design Inc.
-- VHDL Training Classes
-- 11898 SW 128th Ave. Tigard, Or 97223
-- http://www.SynthWorks.com
--
-- Revision History:
-- Date Version Description
-- 01/2008: 0.1 Initial revision
-- Numerous revisions for VHDL Testbenches and Verification
-- 02/2009: 1.0 First Public Released Version
-- 02/25/2009 1.1 Replaced reference to std_2008 with a reference
-- to ieee_proposed.standard_additions.all ;
-- 03/01/2011 2.0 STANDARD VERSION
-- Fixed abstraction by moving RandomParmType to RandomPkg.vhd
-- 4/2013 2013.04 No Changes
-- 5/2013 2013.05 No Changes
-- 1/2015 2015.01 Changed Assert/Report to Alert
-- 6/2015 2015.06 Changed GenRandSeed to impure
--
--
-- Copyright (c) 2008 - 2015 by SynthWorks Design Inc. All rights reserved.
--
-- Verbatim copies of this source file may be used and
-- distributed without restriction.
--
-- This source file is free software; you can redistribute it
-- and/or modify it under the terms of the ARTISTIC License
-- as published by The Perl Foundation; either version 2.0 of
-- the License, or (at your option) any later version.
--
-- This source 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 Artistic License for details.
--
-- You should have received a copy of the license with this source.
-- If not download it from,
-- http://www.perlfoundation.org/artistic_license_2_0
--
library ieee ;
use ieee.math_real.all ;
use std.textio.all ;
use work.OsvvmGlobalPkg.all ;
use work.AlertLogPkg.all ;
-- comment out following 2 lines with VHDL-2008. Leave in for VHDL-2002
-- library ieee_proposed ; -- remove with VHDL-2008
-- use ieee_proposed.standard_additions.all ; -- remove with VHDL-2008
package RandomBasePkg is
-- RandomSeedType and Uniform can be replaced by any procedure that
-- produces a uniform distribution with 0 <= Value < 1 or 0 < Value < 1
-- and maintains the same call interface
type RandomSeedType is array (1 to 2) of integer ;
procedure Uniform (Result : out real ; Seed : inout RandomSeedType) ;
-- Translate from integer_vector, integer, or string to RandomSeedType
-- Required by RandomPkg.InitSeed
-- GenRandSeed makes sure all values are in a valid range
impure function GenRandSeed(IV : integer_vector) return RandomSeedType ;
impure function GenRandSeed(I : integer) return RandomSeedType ;
impure function GenRandSeed(S : string) return RandomSeedType ;
-- IO for RandomSeedType. If use subtype, then create aliases here
-- in a similar fashion VHDL-2008 std_logic_textio.
-- Not required by RandomPkg
function to_string(A : RandomSeedType) return string ;
procedure write(variable L: inout line ; A : RandomSeedType ) ;
procedure read (variable L: inout line ; A : out RandomSeedType ; good : out boolean ) ;
procedure read (variable L: inout line ; A : out RandomSeedType ) ;
end RandomBasePkg ;
--- ///////////////////////////////////////////////////////////////////////////
--- ///////////////////////////////////////////////////////////////////////////
--- ///////////////////////////////////////////////////////////////////////////
package body RandomBasePkg is
-----------------------------------------------------------------
-- Uniform
-- Generate a random number with a Uniform distribution
-- Required by RandomPkg. All randomization is derived from here.
-- Value produced must be either:
-- 0 <= Value < 1 or 0 < Value < 1
--
-- Current version uses ieee.math_real.Uniform
-- This abstraction allows higher precision version
-- of a uniform distribution to be used provided
--
procedure Uniform (
Result : out real ;
Seed : inout RandomSeedType
) is
begin
ieee.math_real.Uniform (Seed(Seed'left), Seed(Seed'right), Result) ;
end procedure Uniform ;
-----------------------------------------------------------------
-- GenRandSeed
-- Convert integer_vector to RandomSeedType
-- Uniform requires two seed values of the form:
-- 1 <= SEED1 <= 2147483562; 1 <= SEED2 <= 2147483398
--
-- if 2 seed values are passed to GenRandSeed and they are
-- in the above range, then they must remain unmodified.
--
impure function GenRandSeed(IV : integer_vector) return RandomSeedType is
alias iIV : integer_vector(1 to IV'length) is IV ;
variable Seed1 : integer ;
variable Seed2 : integer ;
constant SEED1_MAX : integer := 2147483562 ;
constant SEED2_MAX : integer := 2147483398 ;
begin
if iIV'Length <= 0 then -- no seed
Alert(OSVVM_ALERTLOG_ID, "RandomBasePkg.GenRandSeed received NULL integer_vector", FAILURE) ;
return (3, 17) ; -- if continue seed = (3, 17)
elsif iIV'Length = 1 then -- one seed value
-- inefficient handling, but condition is unlikely
return GenRandSeed(iIV(1)) ; -- generate a seed
else -- only use the left two values
-- 1 <= SEED1 <= 2147483562
-- mod returns 0 to MAX-1, the -1 adjusts legal values, +1 adjusts them back
Seed1 := ((iIV(1)-1) mod SEED1_MAX) + 1 ;
-- 1 <= SEED2 <= 2147483398
Seed2 := ((iIV(2)-1) mod SEED2_MAX) + 1 ;
return (Seed1, Seed2) ;
end if ;
end function GenRandSeed ;
-----------------------------------------------------------------
-- GenRandSeed
-- transform a single integer into the internal seed
--
impure function GenRandSeed(I : integer) return RandomSeedType is
variable result : integer_vector(1 to 2) ;
begin
result(1) := I ;
result(2) := I/3 + 1 ;
return GenRandSeed(result) ; -- make value ranges legal
end function GenRandSeed ;
-----------------------------------------------------------------
-- GenRandSeed
-- transform a string value into the internal seed
-- usage: RV.GenRandSeed(RV'instance_path));
--
impure function GenRandSeed(S : string) return RandomSeedType is
constant LEN : integer := S'length ;
constant HALF_LEN : integer := LEN/2 ;
alias revS : string(LEN downto 1) is S ;
variable result : integer_vector(1 to 2) ;
variable temp : integer := 0 ;
begin
for i in 1 to HALF_LEN loop
temp := (temp + character'pos(revS(i))) mod (integer'right - 2**8) ;
end loop ;
result(1) := temp ;
for i in HALF_LEN + 1 to LEN loop
temp := (temp + character'pos(revS(i))) mod (integer'right - 2**8) ;
end loop ;
result(2) := temp ;
return GenRandSeed(result) ; -- make value ranges legal
end function GenRandSeed ;
-----------------------------------------------------------------
function to_string(A : RandomSeedType) return string is
begin
return to_string(A(A'left)) & " " & to_string(A(A'right)) ;
end function to_string ;
-----------------------------------------------------------------
procedure write(variable L: inout line ; A : RandomSeedType ) is
begin
write(L, to_string(A)) ;
end procedure ;
-----------------------------------------------------------------
procedure read(variable L: inout line ; A : out RandomSeedType ; good : out boolean ) is
variable iReadValid : boolean ;
begin
for i in A'range loop
read(L, A(i), iReadValid) ;
exit when not iReadValid ;
end loop ;
good := iReadValid ;
end procedure read ;
-----------------------------------------------------------------
procedure read(variable L: inout line ; A : out RandomSeedType ) is
variable ReadValid : boolean ;
begin
read(L, A, ReadValid) ;
AlertIfNot(ReadValid, OSVVM_ALERTLOG_ID, "RandomBasePkg.read[line, RandomSeedType] failed", FAILURE) ;
end procedure read ;
end RandomBasePkg ;
|
