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4a776f0a HS |
1 | /* |
2 | * DMA Engine test module | |
3 | * | |
4 | * Copyright (C) 2007 Atmel Corporation | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | #include <linux/delay.h> | |
11 | #include <linux/dmaengine.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/kthread.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/moduleparam.h> | |
16 | #include <linux/random.h> | |
17 | #include <linux/wait.h> | |
18 | ||
19 | static unsigned int test_buf_size = 16384; | |
20 | module_param(test_buf_size, uint, S_IRUGO); | |
21 | MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer"); | |
22 | ||
23 | static char test_channel[BUS_ID_SIZE]; | |
24 | module_param_string(channel, test_channel, sizeof(test_channel), S_IRUGO); | |
25 | MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)"); | |
26 | ||
27 | static char test_device[BUS_ID_SIZE]; | |
28 | module_param_string(device, test_device, sizeof(test_device), S_IRUGO); | |
29 | MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)"); | |
30 | ||
31 | static unsigned int threads_per_chan = 1; | |
32 | module_param(threads_per_chan, uint, S_IRUGO); | |
33 | MODULE_PARM_DESC(threads_per_chan, | |
34 | "Number of threads to start per channel (default: 1)"); | |
35 | ||
36 | static unsigned int max_channels; | |
37 | module_param(max_channels, uint, S_IRUGO); | |
38 | MODULE_PARM_DESC(nr_channels, | |
39 | "Maximum number of channels to use (default: all)"); | |
40 | ||
41 | /* | |
42 | * Initialization patterns. All bytes in the source buffer has bit 7 | |
43 | * set, all bytes in the destination buffer has bit 7 cleared. | |
44 | * | |
45 | * Bit 6 is set for all bytes which are to be copied by the DMA | |
46 | * engine. Bit 5 is set for all bytes which are to be overwritten by | |
47 | * the DMA engine. | |
48 | * | |
49 | * The remaining bits are the inverse of a counter which increments by | |
50 | * one for each byte address. | |
51 | */ | |
52 | #define PATTERN_SRC 0x80 | |
53 | #define PATTERN_DST 0x00 | |
54 | #define PATTERN_COPY 0x40 | |
55 | #define PATTERN_OVERWRITE 0x20 | |
56 | #define PATTERN_COUNT_MASK 0x1f | |
57 | ||
58 | struct dmatest_thread { | |
59 | struct list_head node; | |
60 | struct task_struct *task; | |
61 | struct dma_chan *chan; | |
62 | u8 *srcbuf; | |
63 | u8 *dstbuf; | |
64 | }; | |
65 | ||
66 | struct dmatest_chan { | |
67 | struct list_head node; | |
68 | struct dma_chan *chan; | |
69 | struct list_head threads; | |
70 | }; | |
71 | ||
72 | /* | |
73 | * These are protected by dma_list_mutex since they're only used by | |
74 | * the DMA client event callback | |
75 | */ | |
76 | static LIST_HEAD(dmatest_channels); | |
77 | static unsigned int nr_channels; | |
78 | ||
79 | static bool dmatest_match_channel(struct dma_chan *chan) | |
80 | { | |
81 | if (test_channel[0] == '\0') | |
82 | return true; | |
83 | return strcmp(chan->dev.bus_id, test_channel) == 0; | |
84 | } | |
85 | ||
86 | static bool dmatest_match_device(struct dma_device *device) | |
87 | { | |
88 | if (test_device[0] == '\0') | |
89 | return true; | |
90 | return strcmp(device->dev->bus_id, test_device) == 0; | |
91 | } | |
92 | ||
93 | static unsigned long dmatest_random(void) | |
94 | { | |
95 | unsigned long buf; | |
96 | ||
97 | get_random_bytes(&buf, sizeof(buf)); | |
98 | return buf; | |
99 | } | |
100 | ||
101 | static void dmatest_init_srcbuf(u8 *buf, unsigned int start, unsigned int len) | |
102 | { | |
103 | unsigned int i; | |
104 | ||
105 | for (i = 0; i < start; i++) | |
106 | buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); | |
107 | for ( ; i < start + len; i++) | |
108 | buf[i] = PATTERN_SRC | PATTERN_COPY | |
109 | | (~i & PATTERN_COUNT_MASK);; | |
110 | for ( ; i < test_buf_size; i++) | |
111 | buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); | |
112 | } | |
113 | ||
114 | static void dmatest_init_dstbuf(u8 *buf, unsigned int start, unsigned int len) | |
115 | { | |
116 | unsigned int i; | |
117 | ||
118 | for (i = 0; i < start; i++) | |
119 | buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); | |
120 | for ( ; i < start + len; i++) | |
121 | buf[i] = PATTERN_DST | PATTERN_OVERWRITE | |
122 | | (~i & PATTERN_COUNT_MASK); | |
123 | for ( ; i < test_buf_size; i++) | |
124 | buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); | |
125 | } | |
126 | ||
127 | static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index, | |
128 | unsigned int counter, bool is_srcbuf) | |
129 | { | |
130 | u8 diff = actual ^ pattern; | |
131 | u8 expected = pattern | (~counter & PATTERN_COUNT_MASK); | |
132 | const char *thread_name = current->comm; | |
133 | ||
134 | if (is_srcbuf) | |
135 | pr_warning("%s: srcbuf[0x%x] overwritten!" | |
136 | " Expected %02x, got %02x\n", | |
137 | thread_name, index, expected, actual); | |
138 | else if ((pattern & PATTERN_COPY) | |
139 | && (diff & (PATTERN_COPY | PATTERN_OVERWRITE))) | |
140 | pr_warning("%s: dstbuf[0x%x] not copied!" | |
141 | " Expected %02x, got %02x\n", | |
142 | thread_name, index, expected, actual); | |
143 | else if (diff & PATTERN_SRC) | |
144 | pr_warning("%s: dstbuf[0x%x] was copied!" | |
145 | " Expected %02x, got %02x\n", | |
146 | thread_name, index, expected, actual); | |
147 | else | |
148 | pr_warning("%s: dstbuf[0x%x] mismatch!" | |
149 | " Expected %02x, got %02x\n", | |
150 | thread_name, index, expected, actual); | |
151 | } | |
152 | ||
153 | static unsigned int dmatest_verify(u8 *buf, unsigned int start, | |
154 | unsigned int end, unsigned int counter, u8 pattern, | |
155 | bool is_srcbuf) | |
156 | { | |
157 | unsigned int i; | |
158 | unsigned int error_count = 0; | |
159 | u8 actual; | |
160 | ||
161 | for (i = start; i < end; i++) { | |
162 | actual = buf[i]; | |
163 | if (actual != (pattern | (~counter & PATTERN_COUNT_MASK))) { | |
164 | if (error_count < 32) | |
165 | dmatest_mismatch(actual, pattern, i, counter, | |
166 | is_srcbuf); | |
167 | error_count++; | |
168 | } | |
169 | counter++; | |
170 | } | |
171 | ||
172 | if (error_count > 32) | |
173 | pr_warning("%s: %u errors suppressed\n", | |
174 | current->comm, error_count - 32); | |
175 | ||
176 | return error_count; | |
177 | } | |
178 | ||
179 | /* | |
180 | * This function repeatedly tests DMA transfers of various lengths and | |
181 | * offsets until it is told to exit by kthread_stop(). There may be | |
182 | * multiple threads running this function in parallel for a single | |
183 | * channel, and there may be multiple channels being tested in | |
184 | * parallel. | |
185 | * | |
186 | * Before each test, the source and destination buffer is initialized | |
187 | * with a known pattern. This pattern is different depending on | |
188 | * whether it's in an area which is supposed to be copied or | |
189 | * overwritten, and different in the source and destination buffers. | |
190 | * So if the DMA engine doesn't copy exactly what we tell it to copy, | |
191 | * we'll notice. | |
192 | */ | |
193 | static int dmatest_func(void *data) | |
194 | { | |
195 | struct dmatest_thread *thread = data; | |
196 | struct dma_chan *chan; | |
197 | const char *thread_name; | |
198 | unsigned int src_off, dst_off, len; | |
199 | unsigned int error_count; | |
200 | unsigned int failed_tests = 0; | |
201 | unsigned int total_tests = 0; | |
202 | dma_cookie_t cookie; | |
203 | enum dma_status status; | |
204 | int ret; | |
205 | ||
206 | thread_name = current->comm; | |
207 | ||
208 | ret = -ENOMEM; | |
209 | thread->srcbuf = kmalloc(test_buf_size, GFP_KERNEL); | |
210 | if (!thread->srcbuf) | |
211 | goto err_srcbuf; | |
212 | thread->dstbuf = kmalloc(test_buf_size, GFP_KERNEL); | |
213 | if (!thread->dstbuf) | |
214 | goto err_dstbuf; | |
215 | ||
216 | smp_rmb(); | |
217 | chan = thread->chan; | |
218 | dma_chan_get(chan); | |
219 | ||
220 | while (!kthread_should_stop()) { | |
221 | total_tests++; | |
222 | ||
223 | len = dmatest_random() % test_buf_size + 1; | |
224 | src_off = dmatest_random() % (test_buf_size - len + 1); | |
225 | dst_off = dmatest_random() % (test_buf_size - len + 1); | |
226 | ||
227 | dmatest_init_srcbuf(thread->srcbuf, src_off, len); | |
228 | dmatest_init_dstbuf(thread->dstbuf, dst_off, len); | |
229 | ||
230 | cookie = dma_async_memcpy_buf_to_buf(chan, | |
231 | thread->dstbuf + dst_off, | |
232 | thread->srcbuf + src_off, | |
233 | len); | |
234 | if (dma_submit_error(cookie)) { | |
235 | pr_warning("%s: #%u: submit error %d with src_off=0x%x " | |
236 | "dst_off=0x%x len=0x%x\n", | |
237 | thread_name, total_tests - 1, cookie, | |
238 | src_off, dst_off, len); | |
239 | msleep(100); | |
240 | failed_tests++; | |
241 | continue; | |
242 | } | |
243 | dma_async_memcpy_issue_pending(chan); | |
244 | ||
245 | do { | |
246 | msleep(1); | |
247 | status = dma_async_memcpy_complete( | |
248 | chan, cookie, NULL, NULL); | |
249 | } while (status == DMA_IN_PROGRESS); | |
250 | ||
251 | if (status == DMA_ERROR) { | |
252 | pr_warning("%s: #%u: error during copy\n", | |
253 | thread_name, total_tests - 1); | |
254 | failed_tests++; | |
255 | continue; | |
256 | } | |
257 | ||
258 | error_count = 0; | |
259 | ||
260 | pr_debug("%s: verifying source buffer...\n", thread_name); | |
261 | error_count += dmatest_verify(thread->srcbuf, 0, src_off, | |
262 | 0, PATTERN_SRC, true); | |
263 | error_count += dmatest_verify(thread->srcbuf, src_off, | |
264 | src_off + len, src_off, | |
265 | PATTERN_SRC | PATTERN_COPY, true); | |
266 | error_count += dmatest_verify(thread->srcbuf, src_off + len, | |
267 | test_buf_size, src_off + len, | |
268 | PATTERN_SRC, true); | |
269 | ||
270 | pr_debug("%s: verifying dest buffer...\n", | |
271 | thread->task->comm); | |
272 | error_count += dmatest_verify(thread->dstbuf, 0, dst_off, | |
273 | 0, PATTERN_DST, false); | |
274 | error_count += dmatest_verify(thread->dstbuf, dst_off, | |
275 | dst_off + len, src_off, | |
276 | PATTERN_SRC | PATTERN_COPY, false); | |
277 | error_count += dmatest_verify(thread->dstbuf, dst_off + len, | |
278 | test_buf_size, dst_off + len, | |
279 | PATTERN_DST, false); | |
280 | ||
281 | if (error_count) { | |
282 | pr_warning("%s: #%u: %u errors with " | |
283 | "src_off=0x%x dst_off=0x%x len=0x%x\n", | |
284 | thread_name, total_tests - 1, error_count, | |
285 | src_off, dst_off, len); | |
286 | failed_tests++; | |
287 | } else { | |
288 | pr_debug("%s: #%u: No errors with " | |
289 | "src_off=0x%x dst_off=0x%x len=0x%x\n", | |
290 | thread_name, total_tests - 1, | |
291 | src_off, dst_off, len); | |
292 | } | |
293 | } | |
294 | ||
295 | ret = 0; | |
296 | dma_chan_put(chan); | |
297 | kfree(thread->dstbuf); | |
298 | err_dstbuf: | |
299 | kfree(thread->srcbuf); | |
300 | err_srcbuf: | |
301 | pr_notice("%s: terminating after %u tests, %u failures (status %d)\n", | |
302 | thread_name, total_tests, failed_tests, ret); | |
303 | return ret; | |
304 | } | |
305 | ||
306 | static void dmatest_cleanup_channel(struct dmatest_chan *dtc) | |
307 | { | |
308 | struct dmatest_thread *thread; | |
309 | struct dmatest_thread *_thread; | |
310 | int ret; | |
311 | ||
312 | list_for_each_entry_safe(thread, _thread, &dtc->threads, node) { | |
313 | ret = kthread_stop(thread->task); | |
314 | pr_debug("dmatest: thread %s exited with status %d\n", | |
315 | thread->task->comm, ret); | |
316 | list_del(&thread->node); | |
317 | kfree(thread); | |
318 | } | |
319 | kfree(dtc); | |
320 | } | |
321 | ||
322 | static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) | |
323 | { | |
324 | struct dmatest_chan *dtc; | |
325 | struct dmatest_thread *thread; | |
326 | unsigned int i; | |
327 | ||
328 | dtc = kmalloc(sizeof(struct dmatest_chan), GFP_ATOMIC); | |
329 | if (!dtc) { | |
330 | pr_warning("dmatest: No memory for %s\n", chan->dev.bus_id); | |
331 | return DMA_NAK; | |
332 | } | |
333 | ||
334 | dtc->chan = chan; | |
335 | INIT_LIST_HEAD(&dtc->threads); | |
336 | ||
337 | for (i = 0; i < threads_per_chan; i++) { | |
338 | thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL); | |
339 | if (!thread) { | |
340 | pr_warning("dmatest: No memory for %s-test%u\n", | |
341 | chan->dev.bus_id, i); | |
342 | break; | |
343 | } | |
344 | thread->chan = dtc->chan; | |
345 | smp_wmb(); | |
346 | thread->task = kthread_run(dmatest_func, thread, "%s-test%u", | |
347 | chan->dev.bus_id, i); | |
348 | if (IS_ERR(thread->task)) { | |
349 | pr_warning("dmatest: Failed to run thread %s-test%u\n", | |
350 | chan->dev.bus_id, i); | |
351 | kfree(thread); | |
352 | break; | |
353 | } | |
354 | ||
355 | /* srcbuf and dstbuf are allocated by the thread itself */ | |
356 | ||
357 | list_add_tail(&thread->node, &dtc->threads); | |
358 | } | |
359 | ||
360 | pr_info("dmatest: Started %u threads using %s\n", i, chan->dev.bus_id); | |
361 | ||
362 | list_add_tail(&dtc->node, &dmatest_channels); | |
363 | nr_channels++; | |
364 | ||
365 | return DMA_ACK; | |
366 | } | |
367 | ||
368 | static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan) | |
369 | { | |
370 | struct dmatest_chan *dtc, *_dtc; | |
371 | ||
372 | list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { | |
373 | if (dtc->chan == chan) { | |
374 | list_del(&dtc->node); | |
375 | dmatest_cleanup_channel(dtc); | |
376 | pr_debug("dmatest: lost channel %s\n", | |
377 | chan->dev.bus_id); | |
378 | return DMA_ACK; | |
379 | } | |
380 | } | |
381 | ||
382 | return DMA_DUP; | |
383 | } | |
384 | ||
385 | /* | |
386 | * Start testing threads as new channels are assigned to us, and kill | |
387 | * them when the channels go away. | |
388 | * | |
389 | * When we unregister the client, all channels are removed so this | |
390 | * will also take care of cleaning things up when the module is | |
391 | * unloaded. | |
392 | */ | |
393 | static enum dma_state_client | |
394 | dmatest_event(struct dma_client *client, struct dma_chan *chan, | |
395 | enum dma_state state) | |
396 | { | |
397 | enum dma_state_client ack = DMA_NAK; | |
398 | ||
399 | switch (state) { | |
400 | case DMA_RESOURCE_AVAILABLE: | |
401 | if (!dmatest_match_channel(chan) | |
402 | || !dmatest_match_device(chan->device)) | |
403 | ack = DMA_DUP; | |
404 | else if (max_channels && nr_channels >= max_channels) | |
405 | ack = DMA_NAK; | |
406 | else | |
407 | ack = dmatest_add_channel(chan); | |
408 | break; | |
409 | ||
410 | case DMA_RESOURCE_REMOVED: | |
411 | ack = dmatest_remove_channel(chan); | |
412 | break; | |
413 | ||
414 | default: | |
415 | pr_info("dmatest: Unhandled event %u (%s)\n", | |
416 | state, chan->dev.bus_id); | |
417 | break; | |
418 | } | |
419 | ||
420 | return ack; | |
421 | } | |
422 | ||
423 | static struct dma_client dmatest_client = { | |
424 | .event_callback = dmatest_event, | |
425 | }; | |
426 | ||
427 | static int __init dmatest_init(void) | |
428 | { | |
429 | dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask); | |
430 | dma_async_client_register(&dmatest_client); | |
431 | dma_async_client_chan_request(&dmatest_client); | |
432 | ||
433 | return 0; | |
434 | } | |
435 | module_init(dmatest_init); | |
436 | ||
437 | static void __exit dmatest_exit(void) | |
438 | { | |
439 | dma_async_client_unregister(&dmatest_client); | |
440 | } | |
441 | module_exit(dmatest_exit); | |
442 | ||
443 | MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>"); | |
444 | MODULE_LICENSE("GPL v2"); |