Commit | Line | Data |
---|---|---|
355a7058 AB |
1 | /* |
2 | * Loopback bridge driver for the Greybus loopback module. | |
3 | * | |
4 | * Copyright 2014 Google Inc. | |
5 | * Copyright 2014 Linaro Ltd. | |
6 | * | |
7 | * Released under the GPLv2 only. | |
8 | */ | |
9 | #include <linux/kernel.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/kthread.h> | |
13 | #include <linux/delay.h> | |
14 | #include <linux/random.h> | |
5679f783 | 15 | #include <linux/sizes.h> |
1ffc12be JH |
16 | #include <asm/div64.h> |
17 | ||
355a7058 AB |
18 | #include "greybus.h" |
19 | ||
20 | struct gb_loopback_stats { | |
21 | u32 min; | |
22 | u32 max; | |
23 | u32 avg; | |
24 | u32 sum; | |
25 | u32 count; | |
26 | }; | |
27 | ||
28 | struct gb_loopback { | |
29 | struct gb_connection *connection; | |
30 | u8 version_major; | |
31 | u8 version_minor; | |
32 | ||
33 | struct task_struct *task; | |
34 | ||
35 | int type; | |
36 | u32 size; | |
e51eafeb | 37 | size_t size_max; |
355a7058 AB |
38 | int ms_wait; |
39 | ||
40 | struct gb_loopback_stats latency; | |
41 | struct gb_loopback_stats throughput; | |
42 | struct gb_loopback_stats frequency; | |
43 | struct timeval ts; | |
44 | struct timeval te; | |
45 | u64 elapsed_nsecs; | |
46 | u32 error; | |
47 | }; | |
48 | ||
91262c3a | 49 | #define GB_LOOPBACK_MS_WAIT_MAX 1000 |
355a7058 AB |
50 | |
51 | /* Define get_version() routine */ | |
52 | define_get_version(gb_loopback, LOOPBACK); | |
53 | ||
54 | /* interface sysfs attributes */ | |
55 | #define gb_loopback_ro_attr(field, type) \ | |
56 | static ssize_t field##_show(struct device *dev, \ | |
57 | struct device_attribute *attr, \ | |
58 | char *buf) \ | |
59 | { \ | |
60 | struct gb_connection *connection = to_gb_connection(dev); \ | |
61 | struct gb_loopback *gb = \ | |
62 | (struct gb_loopback *)connection->private; \ | |
63 | return sprintf(buf, "%"#type"\n", gb->field); \ | |
64 | } \ | |
65 | static DEVICE_ATTR_RO(field) | |
66 | ||
67 | #define gb_loopback_ro_stats_attr(name, field, type) \ | |
68 | static ssize_t name##_##field##_show(struct device *dev, \ | |
69 | struct device_attribute *attr, \ | |
70 | char *buf) \ | |
71 | { \ | |
72 | struct gb_connection *connection = to_gb_connection(dev); \ | |
73 | struct gb_loopback *gb = \ | |
74 | (struct gb_loopback *)connection->private; \ | |
75 | return sprintf(buf, "%"#type"\n", gb->name.field); \ | |
76 | } \ | |
77 | static DEVICE_ATTR_RO(name##_##field) | |
78 | ||
79 | #define gb_loopback_stats_attrs(field) \ | |
80 | gb_loopback_ro_stats_attr(field, min, d); \ | |
81 | gb_loopback_ro_stats_attr(field, max, d); \ | |
82 | gb_loopback_ro_stats_attr(field, avg, d); | |
83 | ||
84 | #define gb_loopback_attr(field, type) \ | |
85 | static ssize_t field##_show(struct device *dev, \ | |
86 | struct device_attribute *attr, \ | |
87 | char *buf) \ | |
88 | { \ | |
89 | struct gb_connection *connection = to_gb_connection(dev); \ | |
90 | struct gb_loopback *gb = \ | |
91 | (struct gb_loopback *)connection->private; \ | |
92 | return sprintf(buf, "%"#type"\n", gb->field); \ | |
93 | } \ | |
94 | static ssize_t field##_store(struct device *dev, \ | |
95 | struct device_attribute *attr, \ | |
96 | const char *buf, \ | |
97 | size_t len) \ | |
98 | { \ | |
99 | int ret; \ | |
100 | struct gb_connection *connection = to_gb_connection(dev); \ | |
101 | struct gb_loopback *gb = \ | |
102 | (struct gb_loopback *)connection->private; \ | |
103 | ret = sscanf(buf, "%"#type, &gb->field); \ | |
355a7058 AB |
104 | if (ret != 1) \ |
105 | return -EINVAL; \ | |
106 | gb_loopback_check_attr(gb); \ | |
107 | return len; \ | |
108 | } \ | |
109 | static DEVICE_ATTR_RW(field) | |
110 | ||
111 | static void gb_loopback_reset_stats(struct gb_loopback *gb); | |
112 | static void gb_loopback_check_attr(struct gb_loopback *gb) | |
113 | { | |
a598f438 BD |
114 | switch (gb->type) { |
115 | case GB_LOOPBACK_TYPE_PING: | |
116 | case GB_LOOPBACK_TYPE_TRANSFER: | |
384a7a3c | 117 | case GB_LOOPBACK_TYPE_SINK: |
a598f438 BD |
118 | break; |
119 | default: | |
120 | gb->type = 0; | |
121 | break; | |
122 | } | |
91262c3a AE |
123 | if (gb->ms_wait > GB_LOOPBACK_MS_WAIT_MAX) |
124 | gb->ms_wait = GB_LOOPBACK_MS_WAIT_MAX; | |
c3bba87a BD |
125 | if (gb->size > gb->size_max) |
126 | gb->size = gb->size_max; | |
355a7058 AB |
127 | gb->error = 0; |
128 | gb_loopback_reset_stats(gb); | |
129 | } | |
130 | ||
131 | /* Time to send and receive one message */ | |
132 | gb_loopback_stats_attrs(latency); | |
133 | /* Number of packet sent per second on this cport */ | |
134 | gb_loopback_stats_attrs(frequency); | |
135 | /* Quantity of data sent and received on this cport */ | |
136 | gb_loopback_stats_attrs(throughput); | |
137 | gb_loopback_ro_attr(error, d); | |
138 | ||
139 | /* | |
140 | * Type of loopback message to send | |
141 | * 0 => Don't send message | |
142 | * 1 => Send ping message continuously (message without payload) | |
143 | * 2 => Send transer message continuously (message with payload) | |
144 | */ | |
145 | gb_loopback_attr(type, d); | |
146 | /* Size of transfer message payload: 0-4096 bytes */ | |
147 | gb_loopback_attr(size, u); | |
48f19ee8 | 148 | /* Time to wait between two messages: 0-1000 ms */ |
355a7058 AB |
149 | gb_loopback_attr(ms_wait, d); |
150 | ||
151 | #define dev_stats_attrs(name) \ | |
152 | &dev_attr_##name##_min.attr, \ | |
153 | &dev_attr_##name##_max.attr, \ | |
154 | &dev_attr_##name##_avg.attr | |
155 | ||
156 | static struct attribute *loopback_attrs[] = { | |
157 | dev_stats_attrs(latency), | |
158 | dev_stats_attrs(frequency), | |
159 | dev_stats_attrs(throughput), | |
160 | &dev_attr_type.attr, | |
161 | &dev_attr_size.attr, | |
162 | &dev_attr_ms_wait.attr, | |
163 | &dev_attr_error.attr, | |
164 | NULL, | |
165 | }; | |
166 | ATTRIBUTE_GROUPS(loopback); | |
167 | ||
384a7a3c BD |
168 | static int gb_loopback_sink(struct gb_loopback *gb, |
169 | struct timeval *tping, u32 len) | |
170 | { | |
171 | struct timeval ts, te; | |
172 | u64 elapsed_nsecs; | |
173 | struct gb_loopback_transfer_request *request; | |
174 | int retval; | |
175 | ||
176 | request = kmalloc(len + sizeof(*request), GFP_KERNEL); | |
177 | if (!request) | |
178 | return -ENOMEM; | |
179 | ||
180 | request->len = cpu_to_le32(len); | |
181 | ||
182 | do_gettimeofday(&ts); | |
183 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_SINK, | |
184 | request, len + sizeof(*request), NULL, 0); | |
c3bba87a | 185 | |
384a7a3c BD |
186 | do_gettimeofday(&te); |
187 | elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts); | |
188 | *tping = ns_to_timeval(elapsed_nsecs); | |
189 | ||
190 | kfree(request); | |
191 | return retval; | |
192 | } | |
193 | ||
355a7058 AB |
194 | static int gb_loopback_transfer(struct gb_loopback *gb, |
195 | struct timeval *tping, u32 len) | |
196 | { | |
197 | struct timeval ts, te; | |
198 | u64 elapsed_nsecs; | |
199 | struct gb_loopback_transfer_request *request; | |
200 | struct gb_loopback_transfer_response *response; | |
201 | int retval; | |
202 | ||
203 | request = kmalloc(len + sizeof(*request), GFP_KERNEL); | |
204 | if (!request) | |
205 | return -ENOMEM; | |
206 | response = kmalloc(len + sizeof(*response), GFP_KERNEL); | |
207 | if (!response) { | |
208 | kfree(request); | |
209 | return -ENOMEM; | |
210 | } | |
211 | ||
212 | request->len = cpu_to_le32(len); | |
213 | ||
214 | do_gettimeofday(&ts); | |
215 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_TRANSFER, | |
216 | request, len + sizeof(*request), | |
217 | response, len + sizeof(*response)); | |
218 | do_gettimeofday(&te); | |
219 | elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts); | |
220 | *tping = ns_to_timeval(elapsed_nsecs); | |
221 | ||
222 | if (retval) | |
223 | goto gb_error; | |
224 | ||
225 | if (memcmp(request->data, response->data, len)) | |
226 | retval = -EREMOTEIO; | |
227 | ||
228 | gb_error: | |
229 | kfree(request); | |
230 | kfree(response); | |
231 | ||
232 | return retval; | |
233 | } | |
234 | ||
235 | static int gb_loopback_ping(struct gb_loopback *gb, struct timeval *tping) | |
236 | { | |
237 | struct timeval ts, te; | |
238 | u64 elapsed_nsecs; | |
239 | int retval; | |
240 | ||
241 | do_gettimeofday(&ts); | |
242 | retval = gb_operation_sync(gb->connection, GB_LOOPBACK_TYPE_PING, | |
243 | NULL, 0, NULL, 0); | |
244 | do_gettimeofday(&te); | |
245 | elapsed_nsecs = timeval_to_ns(&te) - timeval_to_ns(&ts); | |
246 | *tping = ns_to_timeval(elapsed_nsecs); | |
247 | ||
248 | return retval; | |
249 | } | |
250 | ||
ac1c2840 AE |
251 | static int gb_loopback_request_recv(u8 type, struct gb_operation *operation) |
252 | { | |
253 | struct gb_connection *connection = operation->connection; | |
c3bba87a | 254 | struct gb_loopback *gb = connection->private; |
ac1c2840 AE |
255 | struct gb_loopback_transfer_request *request; |
256 | struct gb_loopback_transfer_response *response; | |
e51eafeb | 257 | size_t len; |
ac1c2840 AE |
258 | |
259 | /* By convention, the AP initiates the version operation */ | |
260 | switch (type) { | |
261 | case GB_LOOPBACK_TYPE_PROTOCOL_VERSION: | |
262 | dev_err(&connection->dev, | |
263 | "module-initiated version operation\n"); | |
264 | return -EINVAL; | |
265 | case GB_LOOPBACK_TYPE_PING: | |
384a7a3c | 266 | case GB_LOOPBACK_TYPE_SINK: |
ac1c2840 AE |
267 | return 0; |
268 | case GB_LOOPBACK_TYPE_TRANSFER: | |
269 | if (operation->request->payload_size < sizeof(*request)) { | |
270 | dev_err(&connection->dev, | |
271 | "transfer request too small (%zu < %zu)\n", | |
272 | operation->request->payload_size, | |
273 | sizeof(*request)); | |
274 | return -EINVAL; /* -EMSGSIZE */ | |
275 | } | |
276 | request = operation->request->payload; | |
277 | len = le32_to_cpu(request->len); | |
c3bba87a BD |
278 | if (len > gb->size_max) { |
279 | dev_err(&connection->dev, | |
280 | "transfer request too large (%zu > %zu)\n", | |
281 | len, gb->size_max); | |
282 | return -EINVAL; | |
283 | } | |
284 | ||
ac1c2840 | 285 | if (len) { |
1c7658cf JH |
286 | if (!gb_operation_response_alloc(operation, len, |
287 | GFP_KERNEL)) { | |
ac1c2840 AE |
288 | dev_err(&connection->dev, |
289 | "error allocating response\n"); | |
290 | return -ENOMEM; | |
291 | } | |
292 | response = operation->response->payload; | |
293 | memcpy(response->data, request->data, len); | |
294 | } | |
295 | return 0; | |
296 | default: | |
297 | dev_err(&connection->dev, | |
298 | "unsupported request: %hhu\n", type); | |
299 | return -EINVAL; | |
300 | } | |
301 | } | |
302 | ||
355a7058 AB |
303 | static void gb_loopback_reset_stats(struct gb_loopback *gb) |
304 | { | |
305 | struct gb_loopback_stats reset = { | |
306 | .min = 0xffffffff, | |
307 | }; | |
308 | memcpy(&gb->latency, &reset, sizeof(struct gb_loopback_stats)); | |
309 | memcpy(&gb->throughput, &reset, sizeof(struct gb_loopback_stats)); | |
310 | memcpy(&gb->frequency, &reset, sizeof(struct gb_loopback_stats)); | |
311 | memset(&gb->ts, 0, sizeof(struct timeval)); | |
312 | } | |
313 | ||
314 | static void gb_loopback_update_stats(struct gb_loopback_stats *stats, | |
315 | u64 elapsed_nsecs) | |
316 | { | |
317 | u32 avg; | |
1ffc12be | 318 | u64 tmp; |
355a7058 AB |
319 | |
320 | if (elapsed_nsecs >= NSEC_PER_SEC) { | |
1ffc12be JH |
321 | if (!stats->count) { |
322 | tmp = elapsed_nsecs; | |
323 | do_div(tmp, NSEC_PER_SEC); | |
324 | avg = stats->sum * tmp; | |
325 | } else { | |
355a7058 | 326 | avg = stats->sum / stats->count; |
1ffc12be | 327 | } |
355a7058 AB |
328 | if (stats->min > avg) |
329 | stats->min = avg; | |
330 | if (stats->max < avg) | |
331 | stats->max = avg; | |
332 | stats->avg = avg; | |
333 | stats->count = 0; | |
334 | stats->sum = 0; | |
335 | } | |
336 | } | |
337 | ||
338 | static void gb_loopback_freq_update(struct gb_loopback *gb) | |
339 | { | |
340 | gb->frequency.sum++; | |
341 | gb_loopback_update_stats(&gb->frequency, gb->elapsed_nsecs); | |
342 | } | |
343 | ||
f7908e4d | 344 | static void gb_loopback_throughput_update(struct gb_loopback *gb) |
355a7058 | 345 | { |
f7908e4d BD |
346 | u32 aggregate_size = sizeof(struct gb_operation_msg_hdr) * 2; |
347 | ||
348 | switch (gb->type) { | |
349 | case GB_LOOPBACK_TYPE_PING: | |
350 | break; | |
351 | case GB_LOOPBACK_TYPE_SINK: | |
352 | aggregate_size += sizeof(struct gb_loopback_transfer_request) + | |
353 | gb->size; | |
354 | break; | |
355 | case GB_LOOPBACK_TYPE_TRANSFER: | |
356 | aggregate_size += sizeof(struct gb_loopback_transfer_request) + | |
357 | sizeof(struct gb_loopback_transfer_response) + | |
358 | gb->size * 2; | |
359 | break; | |
360 | default: | |
361 | return; | |
362 | } | |
363 | gb->throughput.sum += aggregate_size; | |
355a7058 AB |
364 | gb_loopback_update_stats(&gb->throughput, gb->elapsed_nsecs); |
365 | } | |
366 | ||
367 | static void gb_loopback_latency_update(struct gb_loopback *gb, | |
368 | struct timeval *tlat) | |
369 | { | |
370 | u32 lat; | |
1ffc12be | 371 | u64 tmp; |
355a7058 | 372 | |
1ffc12be JH |
373 | tmp = timeval_to_ns(tlat); |
374 | do_div(tmp, NSEC_PER_MSEC); | |
375 | lat = tmp; | |
355a7058 AB |
376 | |
377 | if (gb->latency.min > lat) | |
378 | gb->latency.min = lat; | |
379 | if (gb->latency.max < lat) | |
380 | gb->latency.max = lat; | |
381 | gb->latency.sum += lat; | |
382 | gb->latency.count++; | |
383 | gb_loopback_update_stats(&gb->latency, gb->elapsed_nsecs); | |
384 | } | |
385 | ||
386 | static int gb_loopback_fn(void *data) | |
387 | { | |
388 | int error = 0; | |
389 | struct timeval tlat = {0, 0}; | |
390 | struct gb_loopback *gb = (struct gb_loopback *)data; | |
391 | ||
392 | while (!kthread_should_stop()) { | |
a598f438 | 393 | if (!gb->type) { |
355a7058 AB |
394 | msleep(1000); |
395 | continue; | |
396 | } | |
3156be7d BD |
397 | if (gb->ts.tv_usec == 0 && gb->ts.tv_sec == 0) |
398 | do_gettimeofday(&gb->ts); | |
a598f438 | 399 | if (gb->type == GB_LOOPBACK_TYPE_PING) |
355a7058 | 400 | error = gb_loopback_ping(gb, &tlat); |
a598f438 | 401 | else if (gb->type == GB_LOOPBACK_TYPE_TRANSFER) |
355a7058 | 402 | error = gb_loopback_transfer(gb, &tlat, gb->size); |
384a7a3c BD |
403 | else if (gb->type == GB_LOOPBACK_TYPE_SINK) |
404 | error = gb_loopback_sink(gb, &tlat, gb->size); | |
355a7058 AB |
405 | if (error) |
406 | gb->error++; | |
355a7058 AB |
407 | do_gettimeofday(&gb->te); |
408 | gb->elapsed_nsecs = timeval_to_ns(&gb->te) - | |
409 | timeval_to_ns(&gb->ts); | |
410 | gb_loopback_freq_update(gb); | |
f7908e4d | 411 | gb_loopback_throughput_update(gb); |
355a7058 AB |
412 | gb_loopback_latency_update(gb, &tlat); |
413 | if (gb->elapsed_nsecs >= NSEC_PER_SEC) | |
414 | gb->ts = gb->te; | |
415 | if (gb->ms_wait) | |
416 | msleep(gb->ms_wait); | |
417 | ||
418 | } | |
419 | return 0; | |
420 | } | |
421 | ||
422 | static int gb_loopback_connection_init(struct gb_connection *connection) | |
423 | { | |
424 | struct gb_loopback *gb; | |
425 | int retval; | |
426 | ||
427 | gb = kzalloc(sizeof(*gb), GFP_KERNEL); | |
428 | if (!gb) | |
429 | return -ENOMEM; | |
430 | ||
431 | gb->connection = connection; | |
432 | connection->private = gb; | |
7a51b936 | 433 | retval = sysfs_create_groups(&connection->dev.kobj, loopback_groups); |
355a7058 | 434 | if (retval) |
6f8528e0 | 435 | goto out_free; |
355a7058 AB |
436 | |
437 | /* Check the version */ | |
438 | retval = get_version(gb); | |
439 | if (retval) | |
6f8528e0 | 440 | goto out_get_ver; |
355a7058 | 441 | |
c3bba87a BD |
442 | /* Calculate maximum payload */ |
443 | gb->size_max = gb_operation_get_payload_size_max(connection); | |
444 | if (gb->size_max <= sizeof(struct gb_loopback_transfer_request)) { | |
445 | retval = -EINVAL; | |
446 | goto out_get_ver; | |
447 | } | |
448 | gb->size_max -= sizeof(struct gb_loopback_transfer_request); | |
449 | ||
355a7058 AB |
450 | gb_loopback_reset_stats(gb); |
451 | gb->task = kthread_run(gb_loopback_fn, gb, "gb_loopback"); | |
452 | if (IS_ERR(gb->task)) { | |
69f60347 | 453 | retval = PTR_ERR(gb->task); |
6f8528e0 | 454 | goto out_get_ver; |
355a7058 AB |
455 | } |
456 | ||
457 | return 0; | |
458 | ||
6f8528e0 PT |
459 | out_get_ver: |
460 | sysfs_remove_groups(&connection->dev.kobj, loopback_groups); | |
461 | out_free: | |
355a7058 AB |
462 | kfree(gb); |
463 | return retval; | |
464 | } | |
465 | ||
466 | static void gb_loopback_connection_exit(struct gb_connection *connection) | |
467 | { | |
468 | struct gb_loopback *gb = connection->private; | |
469 | ||
470 | if (!IS_ERR_OR_NULL(gb->task)) | |
471 | kthread_stop(gb->task); | |
7a51b936 | 472 | sysfs_remove_groups(&connection->dev.kobj, loopback_groups); |
355a7058 AB |
473 | kfree(gb); |
474 | } | |
475 | ||
476 | static struct gb_protocol loopback_protocol = { | |
477 | .name = "loopback", | |
478 | .id = GREYBUS_PROTOCOL_LOOPBACK, | |
479 | .major = GB_LOOPBACK_VERSION_MAJOR, | |
480 | .minor = GB_LOOPBACK_VERSION_MINOR, | |
481 | .connection_init = gb_loopback_connection_init, | |
482 | .connection_exit = gb_loopback_connection_exit, | |
ac1c2840 | 483 | .request_recv = gb_loopback_request_recv, |
355a7058 AB |
484 | }; |
485 | ||
486 | gb_protocol_driver(&loopback_protocol); | |
487 | ||
488 | MODULE_LICENSE("GPL v2"); |