1 /* The common simulator framework for GDB, the GNU Debugger.
2
3 Copyright 2002-2013 Free Software Foundation, Inc.
4
5 Contributed by Andrew Cagney and Red Hat.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22
23 #include "hw-main.h"
24
25 #ifdef HAVE_STRING_H
26 #include <string.h>
27 #else
28 #ifdef HAVE_STRINGS_H
29 #include <strings.h>
30 #endif
31 #endif
32
33 /* DEVICE
34
35
36 glue - glue to interconnect and test hardware ports
37
38
39 DESCRIPTION
40
41
42 The glue device provides two functions. Firstly, it provides a
43 mechanism for inspecting and driving the port network. Secondly,
44 it provides a set of boolean primitives that can be used to apply
45 combinatorial operations to the port network.
46
47 Glue devices have a variable number of big endian <<output>>
48 registers. Each register is target-word sized. The registers can
49 be read and written.
50
51 Writing to an output register results in an event being driven
52 (level determined by the value written) on the devices
53 corresponding output port.
54
55 Reading an <<output>> register returns either the last value
56 written or the most recently computed value (for that register) as
57 a result of an event ariving on that port (which ever was computed
58 last).
59
60 At present the following sub device types are available:
61
62 <<glue>>: In addition to driving its output interrupt port with any
63 value written to an interrupt input port is stored in the
64 corresponding <<output>> register. Such input interrupts, however,
65 are not propogated to an output interrupt port.
66
67 <<glue-and>>: The bit-wise AND of the interrupt inputs is computed
68 and then both stored in <<output>> register zero and propogated to
69 output interrupt output port zero.
70
71
72 PROPERTIES
73
74
75 reg = <address> <size> (required)
76
77 Specify the address (within the parent bus) that this device is to
78 live. The address must be 2048 * sizeof (word) (8k in a 32bit
79 simulation) aligned.
80
81
82 interrupt-ranges = <int-number> <range> (optional)
83
84 If present, this specifies the number of valid interrupt inputs (up
85 to the maximum of 2048). By default, <<int-number>> is zero and
86 range is determined by the <<reg>> size.
87
88
89 PORTS
90
91
92 int[0..] (input, output)
93
94 Both an input and an output port.
95
96
97 EXAMPLES
98
99
100 Enable tracing of the device:
101
102 | -t glue-device \
103
104
105 Create source, bitwize-and, and sink glue devices. Since the
106 device at address <<0x10000>> is of size <<8>> it will have two
107 output interrupt ports.
108
109 | -o '/iobus@0xf0000000/glue@0x10000/reg 0x10000 8' \
110 | -o '/iobus@0xf0000000/glue-and@0x20000/reg 0x20000 4' \
111 | -o '/iobus@0xf0000000/glue-and/interrupt-ranges 0 2' \
112 | -o '/iobus@0xf0000000/glue@0x30000/reg 0x30000 4' \
113
114
115 Wire the two source interrupts to the AND device:
116
117 | -o '/iobus@0xf0000000/glue@0x10000 > 0 0 /iobus/glue-and' \
118 | -o '/iobus@0xf0000000/glue@0x10000 > 1 1 /iobus/glue-and' \
119
120
121 Wire the AND device up to the sink so that the and's output is not
122 left open.
123
124 | -o '/iobus@0xf0000000/glue-and > 0 0 /iobus/glue@0x30000' \
125
126
127 With the above configuration. The client program is able to
128 compute a two bit AND. For instance the <<C>> stub below prints 1
129 AND 0.
130
131 | unsigned *input = (void*)0xf0010000;
132 | unsigned *output = (void*)0xf0030000;
133 | unsigned ans;
134 | input[0] = htonl(1);
135 | input[1] = htonl(0);
136 | ans = ntohl(*output);
137 | write_string("AND is ");
138 | write_int(ans);
139 | write_line();
140
141
142 BUGS
143
144
145 A future implementation of this device may support multiple
146 interrupt ranges.
147
148 Some of the devices listed may not yet be fully implemented.
149
150 Additional devices such as a D flip-flop (DFF), an inverter (INV)
151 or a latch (LAT) may prove useful.
152
153 */
154
155
156 enum
157 {
158 max_nr_ports = 2048,
159 };
160
161 enum hw_glue_type
162 {
163 glue_undefined = 0,
164 glue_io,
165 glue_and,
166 glue_nand,
167 glue_or,
168 glue_xor,
169 glue_nor,
170 glue_not,
171 };
172
173 struct hw_glue
174 {
175 enum hw_glue_type type;
176 int int_number;
177 int *input;
178 int nr_inputs;
179 unsigned sizeof_input;
180 /* our output registers */
181 int space;
182 unsigned_word address;
183 unsigned sizeof_output;
184 int *output;
185 int nr_outputs;
186 };
187
188
189 static hw_io_read_buffer_method hw_glue_io_read_buffer;
190 static hw_io_write_buffer_method hw_glue_io_write_buffer;
191 static hw_port_event_method hw_glue_port_event;
192 static const struct hw_port_descriptor hw_glue_ports[];
193
194 static void
hw_glue_finish(struct hw * me)195 hw_glue_finish (struct hw *me)
196 {
197 struct hw_glue *glue = HW_ZALLOC (me, struct hw_glue);
198 const char *name = hw_name (me);
199
200 /* establish our own methods */
201 set_hw_data (me, glue);
202 set_hw_io_read_buffer (me, hw_glue_io_read_buffer);
203 set_hw_io_write_buffer (me, hw_glue_io_write_buffer);
204 set_hw_ports (me, hw_glue_ports);
205 set_hw_port_event (me, hw_glue_port_event);
206
207 /* attach to our parent bus */
208 do_hw_attach_regs (me);
209
210 /* establish the output registers */
211 if (hw_find_property (me, "reg"))
212 {
213 reg_property_spec unit;
214 int reg_nr;
215
216 /* Find a relevant reg entry. */
217 reg_nr = 0;
218 while (hw_find_reg_array_property (me, "reg", reg_nr, &unit)
219 && !hw_unit_size_to_attach_size (hw_parent (me),
220 &unit.size,
221 &glue->sizeof_output,
222 me))
223 reg_nr++;
224
225 /* Check out the size ... */
226 if (glue->sizeof_output == 0)
227 hw_abort (me, "at least one reg property size must be nonzero");
228 if (glue->sizeof_output % sizeof (unsigned_word) != 0)
229 hw_abort (me, "reg property size must be %ld aligned",
230 (long) sizeof (unsigned_word));
231
232 /* ... and the address. */
233 hw_unit_address_to_attach_address (hw_parent (me),
234 &unit.address,
235 &glue->space,
236 &glue->address,
237 me);
238 if (glue->address % (sizeof (unsigned_word) * max_nr_ports) != 0)
239 hw_abort (me, "reg property address must be %ld aligned",
240 (long) (sizeof (unsigned_word) * max_nr_ports));
241
242 glue->nr_outputs = glue->sizeof_output / sizeof (unsigned_word);
243 }
244 else
245 {
246 /* Allow bitwise glue devices to declare only ports. */
247 if (!strcmp (name, "glue"))
248 hw_abort (me, "Missing \"reg\" property");
249
250 glue->nr_outputs = 1;
251 glue->sizeof_output = sizeof (unsigned_word);
252 }
253 glue->output = hw_zalloc (me, glue->sizeof_output);
254
255 /* establish the input ports */
256 {
257 const struct hw_property *ranges;
258
259 ranges = hw_find_property (me, "interrupt-ranges");
260 if (ranges == NULL)
261 {
262 glue->int_number = 0;
263 glue->nr_inputs = glue->nr_outputs;
264 }
265 else if (ranges->sizeof_array != sizeof (unsigned_cell) * 2)
266 {
267 hw_abort (me, "invalid interrupt-ranges property (incorrect size)");
268 }
269 else
270 {
271 const unsigned_cell *int_range = ranges->array;
272
273 glue->int_number = BE2H_cell (int_range[0]);
274 glue->nr_inputs = BE2H_cell (int_range[1]);
275 }
276 glue->sizeof_input = glue->nr_inputs * sizeof (unsigned);
277 glue->input = hw_zalloc (me, glue->sizeof_input);
278 }
279
280 /* determine our type */
281 if (strcmp (name, "glue") == 0)
282 glue->type = glue_io;
283 else if (strcmp (name, "glue-and") == 0)
284 glue->type = glue_and;
285 else if (strcmp (name, "glue-or") == 0)
286 glue->type = glue_or;
287 else if (strcmp (name, "glue-xor") == 0)
288 glue->type = glue_xor;
289 else
290 hw_abort (me, "unimplemented glue type");
291
292 HW_TRACE ((me, "int-number %d, nr_inputs %d, nr_outputs %d",
293 glue->int_number, glue->nr_inputs, glue->nr_outputs));
294 }
295
296 static unsigned
hw_glue_io_read_buffer(struct hw * me,void * dest,int space,unsigned_word addr,unsigned nr_bytes)297 hw_glue_io_read_buffer (struct hw *me,
298 void *dest,
299 int space,
300 unsigned_word addr,
301 unsigned nr_bytes)
302 {
303 struct hw_glue *glue = (struct hw_glue *) hw_data (me);
304 int reg = ((addr - glue->address) / sizeof (unsigned_word)) % glue->nr_outputs;
305
306 if (nr_bytes != sizeof (unsigned_word)
307 || (addr % sizeof (unsigned_word)) != 0)
308 hw_abort (me, "missaligned read access (%d:0x%lx:%d) not supported",
309 space, (unsigned long)addr, nr_bytes);
310
311 *(unsigned_word *)dest = H2BE_4 (glue->output[reg]);
312
313 HW_TRACE ((me, "read - port %d (0x%lx), level %d",
314 reg, (unsigned long) addr, glue->output[reg]));
315
316 return nr_bytes;
317 }
318
319
320 static unsigned
hw_glue_io_write_buffer(struct hw * me,const void * source,int space,unsigned_word addr,unsigned nr_bytes)321 hw_glue_io_write_buffer (struct hw *me,
322 const void *source,
323 int space,
324 unsigned_word addr,
325 unsigned nr_bytes)
326 {
327 struct hw_glue *glue = (struct hw_glue *) hw_data (me);
328 int reg = ((addr - glue->address) / sizeof (unsigned_word)) % max_nr_ports;
329
330 if (nr_bytes != sizeof (unsigned_word)
331 || (addr % sizeof (unsigned_word)) != 0)
332 hw_abort (me, "missaligned write access (%d:0x%lx:%d) not supported",
333 space, (unsigned long) addr, nr_bytes);
334
335 glue->output[reg] = H2BE_4 (*(unsigned_word *)source);
336
337 HW_TRACE ((me, "write - port %d (0x%lx), level %d",
338 reg, (unsigned long) addr, glue->output[reg]));
339
340 hw_port_event (me, reg, glue->output[reg]);
341
342 return nr_bytes;
343 }
344
345 static void
hw_glue_port_event(struct hw * me,int my_port,struct hw * source,int source_port,int level)346 hw_glue_port_event (struct hw *me,
347 int my_port,
348 struct hw *source,
349 int source_port,
350 int level)
351 {
352 struct hw_glue *glue = (struct hw_glue *) hw_data (me);
353 int i;
354
355 if (my_port < glue->int_number
356 || my_port >= glue->int_number + glue->nr_inputs)
357 hw_abort (me, "port %d outside of valid range", my_port);
358
359 glue->input[my_port - glue->int_number] = level;
360 switch (glue->type)
361 {
362 case glue_io:
363 {
364 int port = my_port % glue->nr_outputs;
365
366 glue->output[port] = level;
367
368 HW_TRACE ((me, "input - port %d (0x%lx), level %d",
369 my_port,
370 (unsigned long) glue->address + port * sizeof (unsigned_word),
371 level));
372 return;
373 }
374 case glue_and:
375 {
376 glue->output[0] = glue->input[0];
377 for (i = 1; i < glue->nr_inputs; i++)
378 glue->output[0] &= glue->input[i];
379 break;
380 }
381 case glue_or:
382 {
383 glue->output[0] = glue->input[0];
384 for (i = 1; i < glue->nr_inputs; i++)
385 glue->output[0] |= glue->input[i];
386 break;
387 }
388 case glue_xor:
389 {
390 glue->output[0] = glue->input[0];
391 for (i = 1; i < glue->nr_inputs; i++)
392 glue->output[0] ^= glue->input[i];
393 break;
394 }
395 default:
396 {
397 hw_abort (me, "operator not implemented");
398 return;
399 }
400 }
401
402 /* If we fell through, we want to generate a port event. */
403 HW_TRACE ((me, "port %d, level %d arrived - output %d",
404 my_port, level, glue->output[0]));
405
406 hw_port_event (me, 0, glue->output[0]);
407 }
408
409
410 static const struct hw_port_descriptor hw_glue_ports[] =
411 {
412 { "int", 0, max_nr_ports, 0 },
413 { NULL, 0, 0, 0 }
414 };
415
416
417 const struct hw_descriptor dv_glue_descriptor[] =
418 {
419 { "glue", hw_glue_finish, },
420 { "glue-and", hw_glue_finish, },
421 { "glue-nand", hw_glue_finish, },
422 { "glue-or", hw_glue_finish, },
423 { "glue-xor", hw_glue_finish, },
424 { "glue-nor", hw_glue_finish, },
425 { "glue-not", hw_glue_finish, },
426 { NULL, NULL },
427 };
428