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
|
/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include "kernel/register.h"
#include "kernel/log.h"
#include <stdlib.h>
#include <sstream>
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
void normalize_sig(RTLIL::Module *module, RTLIL::SigSpec &sig)
{
for (auto &conn : module->connections())
sig.replace(conn.first, conn.second);
}
bool find_sig_before_dff(RTLIL::Module *module, std::vector<RTLIL::Cell*> &dff_cells, RTLIL::SigSpec &sig, RTLIL::SigSpec &clk, bool &clk_polarity, bool after = false)
{
normalize_sig(module, sig);
for (auto &bit : sig)
{
if (bit.wire == NULL)
continue;
for (auto cell : dff_cells)
{
if (clk != RTLIL::SigSpec(RTLIL::State::Sx)) {
if (cell->getPort("\\CLK") != clk)
continue;
if (cell->parameters["\\CLK_POLARITY"].as_bool() != clk_polarity)
continue;
}
RTLIL::SigSpec q_norm = cell->getPort(after ? "\\D" : "\\Q");
normalize_sig(module, q_norm);
RTLIL::SigSpec d = q_norm.extract(bit, &cell->getPort(after ? "\\Q" : "\\D"));
if (d.size() != 1)
continue;
bit = d;
clk = cell->getPort("\\CLK");
clk_polarity = cell->parameters["\\CLK_POLARITY"].as_bool();
goto replaced_this_bit;
}
return false;
replaced_this_bit:;
}
return true;
}
void handle_wr_cell(RTLIL::Module *module, std::vector<RTLIL::Cell*> &dff_cells, RTLIL::Cell *cell)
{
log("Checking cell `%s' in module `%s': ", cell->name.c_str(), module->name.c_str());
RTLIL::SigSpec clk = RTLIL::SigSpec(RTLIL::State::Sx);
bool clk_polarity = 0;
RTLIL::SigSpec sig_addr = cell->getPort("\\ADDR");
if (!find_sig_before_dff(module, dff_cells, sig_addr, clk, clk_polarity)) {
log("no (compatible) $dff for address input found.\n");
return;
}
RTLIL::SigSpec sig_data = cell->getPort("\\DATA");
if (!find_sig_before_dff(module, dff_cells, sig_data, clk, clk_polarity)) {
log("no (compatible) $dff for data input found.\n");
return;
}
RTLIL::SigSpec sig_en = cell->getPort("\\EN");
if (!find_sig_before_dff(module, dff_cells, sig_en, clk, clk_polarity)) {
log("no (compatible) $dff for enable input found.\n");
return;
}
if (clk != RTLIL::SigSpec(RTLIL::State::Sx)) {
cell->setPort("\\CLK", clk);
cell->setPort("\\ADDR", sig_addr);
cell->setPort("\\DATA", sig_data);
cell->setPort("\\EN", sig_en);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
log("merged $dff to cell.\n");
return;
}
log("no (compatible) $dff found.\n");
}
void disconnect_dff(RTLIL::Module *module, RTLIL::SigSpec sig)
{
normalize_sig(module, sig);
sig.sort_and_unify();
std::stringstream sstr;
sstr << "$memory_dff_disconnected$" << (autoidx++);
RTLIL::SigSpec new_sig = module->addWire(sstr.str(), sig.size());
for (auto cell : module->cells())
if (cell->type == "$dff") {
RTLIL::SigSpec new_q = cell->getPort("\\Q");
new_q.replace(sig, new_sig);
cell->setPort("\\Q", new_q);
}
}
void handle_rd_cell(RTLIL::Module *module, std::vector<RTLIL::Cell*> &dff_cells, RTLIL::Cell *cell)
{
log("Checking cell `%s' in module `%s': ", cell->name.c_str(), module->name.c_str());
bool clk_polarity = 0;
RTLIL::SigSpec clk_data = RTLIL::SigSpec(RTLIL::State::Sx);
RTLIL::SigSpec sig_data = cell->getPort("\\DATA");
if (find_sig_before_dff(module, dff_cells, sig_data, clk_data, clk_polarity, true) &&
clk_data != RTLIL::SigSpec(RTLIL::State::Sx))
{
disconnect_dff(module, sig_data);
cell->setPort("\\CLK", clk_data);
cell->setPort("\\DATA", sig_data);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
cell->parameters["\\TRANSPARENT"] = RTLIL::Const(0);
log("merged data $dff to cell.\n");
return;
}
RTLIL::SigSpec clk_addr = RTLIL::SigSpec(RTLIL::State::Sx);
RTLIL::SigSpec sig_addr = cell->getPort("\\ADDR");
if (find_sig_before_dff(module, dff_cells, sig_addr, clk_addr, clk_polarity) &&
clk_addr != RTLIL::SigSpec(RTLIL::State::Sx))
{
cell->setPort("\\CLK", clk_addr);
cell->setPort("\\ADDR", sig_addr);
cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1);
cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity);
cell->parameters["\\TRANSPARENT"] = RTLIL::Const(1);
log("merged address $dff to cell.\n");
return;
}
log("no (compatible) $dff found.\n");
}
void handle_module(RTLIL::Module *module, bool flag_wr_only)
{
std::vector<RTLIL::Cell*> dff_cells;
for (auto cell : module->cells())
if (cell->type == "$dff")
dff_cells.push_back(cell);
for (auto cell : module->selected_cells())
if (cell->type == "$memwr" && !cell->parameters["\\CLK_ENABLE"].as_bool())
handle_wr_cell(module, dff_cells, cell);
if (!flag_wr_only)
for (auto cell : module->selected_cells())
if (cell->type == "$memrd" && !cell->parameters["\\CLK_ENABLE"].as_bool())
handle_rd_cell(module, dff_cells, cell);
}
struct MemoryDffPass : public Pass {
MemoryDffPass() : Pass("memory_dff", "merge input/output DFFs into memories") { }
virtual void help()
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" memory_dff [options] [selection]\n");
log("\n");
log("This pass detects DFFs at memory ports and merges them into the memory port.\n");
log("I.e. it consumes an asynchronous memory port and the flip-flops at its\n");
log("interface and yields a synchronous memory port.\n");
log("\n");
log(" -wr_only\n");
log(" do not merge registers on read ports\n");
log("\n");
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
bool flag_wr_only = false;
log_header("Executing MEMORY_DFF pass (merging $dff cells to $memrd and $memwr).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
if (args[argidx] == "-wr_only") {
flag_wr_only = true;
continue;
}
break;
}
extra_args(args, argidx, design);
for (auto mod : design->selected_modules())
handle_module(mod, flag_wr_only);
}
} MemoryDffPass;
PRIVATE_NAMESPACE_END
|
