[3/4] I/OAT: fix async_tx.callback checking
[linux-2.6.git] / drivers / dma / dmatest.c
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         /* Have we already been told about this channel? */
329         list_for_each_entry(dtc, &dmatest_channels, node)
330                 if (dtc->chan == chan)
331                         return DMA_DUP;
332
333         dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
334         if (!dtc) {
335                 pr_warning("dmatest: No memory for %s\n", chan->dev.bus_id);
336                 return DMA_NAK;
337         }
338
339         dtc->chan = chan;
340         INIT_LIST_HEAD(&dtc->threads);
341
342         for (i = 0; i < threads_per_chan; i++) {
343                 thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
344                 if (!thread) {
345                         pr_warning("dmatest: No memory for %s-test%u\n",
346                                         chan->dev.bus_id, i);
347                         break;
348                 }
349                 thread->chan = dtc->chan;
350                 smp_wmb();
351                 thread->task = kthread_run(dmatest_func, thread, "%s-test%u",
352                                 chan->dev.bus_id, i);
353                 if (IS_ERR(thread->task)) {
354                         pr_warning("dmatest: Failed to run thread %s-test%u\n",
355                                         chan->dev.bus_id, i);
356                         kfree(thread);
357                         break;
358                 }
359
360                 /* srcbuf and dstbuf are allocated by the thread itself */
361
362                 list_add_tail(&thread->node, &dtc->threads);
363         }
364
365         pr_info("dmatest: Started %u threads using %s\n", i, chan->dev.bus_id);
366
367         list_add_tail(&dtc->node, &dmatest_channels);
368         nr_channels++;
369
370         return DMA_ACK;
371 }
372
373 static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan)
374 {
375         struct dmatest_chan     *dtc, *_dtc;
376
377         list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) {
378                 if (dtc->chan == chan) {
379                         list_del(&dtc->node);
380                         dmatest_cleanup_channel(dtc);
381                         pr_debug("dmatest: lost channel %s\n",
382                                         chan->dev.bus_id);
383                         return DMA_ACK;
384                 }
385         }
386
387         return DMA_DUP;
388 }
389
390 /*
391  * Start testing threads as new channels are assigned to us, and kill
392  * them when the channels go away.
393  *
394  * When we unregister the client, all channels are removed so this
395  * will also take care of cleaning things up when the module is
396  * unloaded.
397  */
398 static enum dma_state_client
399 dmatest_event(struct dma_client *client, struct dma_chan *chan,
400                 enum dma_state state)
401 {
402         enum dma_state_client   ack = DMA_NAK;
403
404         switch (state) {
405         case DMA_RESOURCE_AVAILABLE:
406                 if (!dmatest_match_channel(chan)
407                                 || !dmatest_match_device(chan->device))
408                         ack = DMA_DUP;
409                 else if (max_channels && nr_channels >= max_channels)
410                         ack = DMA_NAK;
411                 else
412                         ack = dmatest_add_channel(chan);
413                 break;
414
415         case DMA_RESOURCE_REMOVED:
416                 ack = dmatest_remove_channel(chan);
417                 break;
418
419         default:
420                 pr_info("dmatest: Unhandled event %u (%s)\n",
421                                 state, chan->dev.bus_id);
422                 break;
423         }
424
425         return ack;
426 }
427
428 static struct dma_client dmatest_client = {
429         .event_callback = dmatest_event,
430 };
431
432 static int __init dmatest_init(void)
433 {
434         dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask);
435         dma_async_client_register(&dmatest_client);
436         dma_async_client_chan_request(&dmatest_client);
437
438         return 0;
439 }
440 module_init(dmatest_init);
441
442 static void __exit dmatest_exit(void)
443 {
444         dma_async_client_unregister(&dmatest_client);
445 }
446 module_exit(dmatest_exit);
447
448 MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>");
449 MODULE_LICENSE("GPL v2");