xref: /linux/drivers/dma/dmatest.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * DMA Engine test module
3  *
4  * Copyright (C) 2007 Atmel Corporation
5  * Copyright (C) 2013 Intel Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/delay.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/dmaengine.h>
16 #include <linux/freezer.h>
17 #include <linux/init.h>
18 #include <linux/kthread.h>
19 #include <linux/sched/task.h>
20 #include <linux/module.h>
21 #include <linux/moduleparam.h>
22 #include <linux/random.h>
23 #include <linux/slab.h>
24 #include <linux/wait.h>
25 
26 static unsigned int test_buf_size = 16384;
27 module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
28 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
29 
30 static char test_channel[20];
31 module_param_string(channel, test_channel, sizeof(test_channel),
32 		S_IRUGO | S_IWUSR);
33 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
34 
35 static char test_device[32];
36 module_param_string(device, test_device, sizeof(test_device),
37 		S_IRUGO | S_IWUSR);
38 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
39 
40 static unsigned int threads_per_chan = 1;
41 module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
42 MODULE_PARM_DESC(threads_per_chan,
43 		"Number of threads to start per channel (default: 1)");
44 
45 static unsigned int max_channels;
46 module_param(max_channels, uint, S_IRUGO | S_IWUSR);
47 MODULE_PARM_DESC(max_channels,
48 		"Maximum number of channels to use (default: all)");
49 
50 static unsigned int iterations;
51 module_param(iterations, uint, S_IRUGO | S_IWUSR);
52 MODULE_PARM_DESC(iterations,
53 		"Iterations before stopping test (default: infinite)");
54 
55 static unsigned int sg_buffers = 1;
56 module_param(sg_buffers, uint, S_IRUGO | S_IWUSR);
57 MODULE_PARM_DESC(sg_buffers,
58 		"Number of scatter gather buffers (default: 1)");
59 
60 static unsigned int dmatest;
61 module_param(dmatest, uint, S_IRUGO | S_IWUSR);
62 MODULE_PARM_DESC(dmatest,
63 		"dmatest 0-memcpy 1-slave_sg (default: 0)");
64 
65 static unsigned int xor_sources = 3;
66 module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
67 MODULE_PARM_DESC(xor_sources,
68 		"Number of xor source buffers (default: 3)");
69 
70 static unsigned int pq_sources = 3;
71 module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
72 MODULE_PARM_DESC(pq_sources,
73 		"Number of p+q source buffers (default: 3)");
74 
75 static int timeout = 3000;
76 module_param(timeout, uint, S_IRUGO | S_IWUSR);
77 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
78 		 "Pass -1 for infinite timeout");
79 
80 static bool noverify;
81 module_param(noverify, bool, S_IRUGO | S_IWUSR);
82 MODULE_PARM_DESC(noverify, "Disable random data setup and verification");
83 
84 static bool verbose;
85 module_param(verbose, bool, S_IRUGO | S_IWUSR);
86 MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
87 
88 /**
89  * struct dmatest_params - test parameters.
90  * @buf_size:		size of the memcpy test buffer
91  * @channel:		bus ID of the channel to test
92  * @device:		bus ID of the DMA Engine to test
93  * @threads_per_chan:	number of threads to start per channel
94  * @max_channels:	maximum number of channels to use
95  * @iterations:		iterations before stopping test
96  * @xor_sources:	number of xor source buffers
97  * @pq_sources:		number of p+q source buffers
98  * @timeout:		transfer timeout in msec, -1 for infinite timeout
99  */
100 struct dmatest_params {
101 	unsigned int	buf_size;
102 	char		channel[20];
103 	char		device[32];
104 	unsigned int	threads_per_chan;
105 	unsigned int	max_channels;
106 	unsigned int	iterations;
107 	unsigned int	xor_sources;
108 	unsigned int	pq_sources;
109 	int		timeout;
110 	bool		noverify;
111 };
112 
113 /**
114  * struct dmatest_info - test information.
115  * @params:		test parameters
116  * @lock:		access protection to the fields of this structure
117  */
118 static struct dmatest_info {
119 	/* Test parameters */
120 	struct dmatest_params	params;
121 
122 	/* Internal state */
123 	struct list_head	channels;
124 	unsigned int		nr_channels;
125 	struct mutex		lock;
126 	bool			did_init;
127 } test_info = {
128 	.channels = LIST_HEAD_INIT(test_info.channels),
129 	.lock = __MUTEX_INITIALIZER(test_info.lock),
130 };
131 
132 static int dmatest_run_set(const char *val, const struct kernel_param *kp);
133 static int dmatest_run_get(char *val, const struct kernel_param *kp);
134 static const struct kernel_param_ops run_ops = {
135 	.set = dmatest_run_set,
136 	.get = dmatest_run_get,
137 };
138 static bool dmatest_run;
139 module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
140 MODULE_PARM_DESC(run, "Run the test (default: false)");
141 
142 /* Maximum amount of mismatched bytes in buffer to print */
143 #define MAX_ERROR_COUNT		32
144 
145 /*
146  * Initialization patterns. All bytes in the source buffer has bit 7
147  * set, all bytes in the destination buffer has bit 7 cleared.
148  *
149  * Bit 6 is set for all bytes which are to be copied by the DMA
150  * engine. Bit 5 is set for all bytes which are to be overwritten by
151  * the DMA engine.
152  *
153  * The remaining bits are the inverse of a counter which increments by
154  * one for each byte address.
155  */
156 #define PATTERN_SRC		0x80
157 #define PATTERN_DST		0x00
158 #define PATTERN_COPY		0x40
159 #define PATTERN_OVERWRITE	0x20
160 #define PATTERN_COUNT_MASK	0x1f
161 
162 struct dmatest_thread {
163 	struct list_head	node;
164 	struct dmatest_info	*info;
165 	struct task_struct	*task;
166 	struct dma_chan		*chan;
167 	u8			**srcs;
168 	u8			**usrcs;
169 	u8			**dsts;
170 	u8			**udsts;
171 	enum dma_transaction_type type;
172 	bool			done;
173 };
174 
175 struct dmatest_chan {
176 	struct list_head	node;
177 	struct dma_chan		*chan;
178 	struct list_head	threads;
179 };
180 
181 static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
182 static bool wait;
183 
184 static bool is_threaded_test_run(struct dmatest_info *info)
185 {
186 	struct dmatest_chan *dtc;
187 
188 	list_for_each_entry(dtc, &info->channels, node) {
189 		struct dmatest_thread *thread;
190 
191 		list_for_each_entry(thread, &dtc->threads, node) {
192 			if (!thread->done)
193 				return true;
194 		}
195 	}
196 
197 	return false;
198 }
199 
200 static int dmatest_wait_get(char *val, const struct kernel_param *kp)
201 {
202 	struct dmatest_info *info = &test_info;
203 	struct dmatest_params *params = &info->params;
204 
205 	if (params->iterations)
206 		wait_event(thread_wait, !is_threaded_test_run(info));
207 	wait = true;
208 	return param_get_bool(val, kp);
209 }
210 
211 static const struct kernel_param_ops wait_ops = {
212 	.get = dmatest_wait_get,
213 	.set = param_set_bool,
214 };
215 module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
216 MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
217 
218 static bool dmatest_match_channel(struct dmatest_params *params,
219 		struct dma_chan *chan)
220 {
221 	if (params->channel[0] == '\0')
222 		return true;
223 	return strcmp(dma_chan_name(chan), params->channel) == 0;
224 }
225 
226 static bool dmatest_match_device(struct dmatest_params *params,
227 		struct dma_device *device)
228 {
229 	if (params->device[0] == '\0')
230 		return true;
231 	return strcmp(dev_name(device->dev), params->device) == 0;
232 }
233 
234 static unsigned long dmatest_random(void)
235 {
236 	unsigned long buf;
237 
238 	prandom_bytes(&buf, sizeof(buf));
239 	return buf;
240 }
241 
242 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
243 		unsigned int buf_size)
244 {
245 	unsigned int i;
246 	u8 *buf;
247 
248 	for (; (buf = *bufs); bufs++) {
249 		for (i = 0; i < start; i++)
250 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
251 		for ( ; i < start + len; i++)
252 			buf[i] = PATTERN_SRC | PATTERN_COPY
253 				| (~i & PATTERN_COUNT_MASK);
254 		for ( ; i < buf_size; i++)
255 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
256 		buf++;
257 	}
258 }
259 
260 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
261 		unsigned int buf_size)
262 {
263 	unsigned int i;
264 	u8 *buf;
265 
266 	for (; (buf = *bufs); bufs++) {
267 		for (i = 0; i < start; i++)
268 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
269 		for ( ; i < start + len; i++)
270 			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
271 				| (~i & PATTERN_COUNT_MASK);
272 		for ( ; i < buf_size; i++)
273 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
274 	}
275 }
276 
277 static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
278 		unsigned int counter, bool is_srcbuf)
279 {
280 	u8		diff = actual ^ pattern;
281 	u8		expected = pattern | (~counter & PATTERN_COUNT_MASK);
282 	const char	*thread_name = current->comm;
283 
284 	if (is_srcbuf)
285 		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
286 			thread_name, index, expected, actual);
287 	else if ((pattern & PATTERN_COPY)
288 			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
289 		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
290 			thread_name, index, expected, actual);
291 	else if (diff & PATTERN_SRC)
292 		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
293 			thread_name, index, expected, actual);
294 	else
295 		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
296 			thread_name, index, expected, actual);
297 }
298 
299 static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
300 		unsigned int end, unsigned int counter, u8 pattern,
301 		bool is_srcbuf)
302 {
303 	unsigned int i;
304 	unsigned int error_count = 0;
305 	u8 actual;
306 	u8 expected;
307 	u8 *buf;
308 	unsigned int counter_orig = counter;
309 
310 	for (; (buf = *bufs); bufs++) {
311 		counter = counter_orig;
312 		for (i = start; i < end; i++) {
313 			actual = buf[i];
314 			expected = pattern | (~counter & PATTERN_COUNT_MASK);
315 			if (actual != expected) {
316 				if (error_count < MAX_ERROR_COUNT)
317 					dmatest_mismatch(actual, pattern, i,
318 							 counter, is_srcbuf);
319 				error_count++;
320 			}
321 			counter++;
322 		}
323 	}
324 
325 	if (error_count > MAX_ERROR_COUNT)
326 		pr_warn("%s: %u errors suppressed\n",
327 			current->comm, error_count - MAX_ERROR_COUNT);
328 
329 	return error_count;
330 }
331 
332 /* poor man's completion - we want to use wait_event_freezable() on it */
333 struct dmatest_done {
334 	bool			done;
335 	wait_queue_head_t	*wait;
336 };
337 
338 static void dmatest_callback(void *arg)
339 {
340 	struct dmatest_done *done = arg;
341 
342 	done->done = true;
343 	wake_up_all(done->wait);
344 }
345 
346 static unsigned int min_odd(unsigned int x, unsigned int y)
347 {
348 	unsigned int val = min(x, y);
349 
350 	return val % 2 ? val : val - 1;
351 }
352 
353 static void result(const char *err, unsigned int n, unsigned int src_off,
354 		   unsigned int dst_off, unsigned int len, unsigned long data)
355 {
356 	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
357 		current->comm, n, err, src_off, dst_off, len, data);
358 }
359 
360 static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
361 		       unsigned int dst_off, unsigned int len,
362 		       unsigned long data)
363 {
364 	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
365 		 current->comm, n, err, src_off, dst_off, len, data);
366 }
367 
368 #define verbose_result(err, n, src_off, dst_off, len, data) ({	\
369 	if (verbose)						\
370 		result(err, n, src_off, dst_off, len, data);	\
371 	else							\
372 		dbg_result(err, n, src_off, dst_off, len, data);\
373 })
374 
375 static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
376 {
377 	unsigned long long per_sec = 1000000;
378 
379 	if (runtime <= 0)
380 		return 0;
381 
382 	/* drop precision until runtime is 32-bits */
383 	while (runtime > UINT_MAX) {
384 		runtime >>= 1;
385 		per_sec <<= 1;
386 	}
387 
388 	per_sec *= val;
389 	do_div(per_sec, runtime);
390 	return per_sec;
391 }
392 
393 static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
394 {
395 	return dmatest_persec(runtime, len >> 10);
396 }
397 
398 /*
399  * This function repeatedly tests DMA transfers of various lengths and
400  * offsets for a given operation type until it is told to exit by
401  * kthread_stop(). There may be multiple threads running this function
402  * in parallel for a single channel, and there may be multiple channels
403  * being tested in parallel.
404  *
405  * Before each test, the source and destination buffer is initialized
406  * with a known pattern. This pattern is different depending on
407  * whether it's in an area which is supposed to be copied or
408  * overwritten, and different in the source and destination buffers.
409  * So if the DMA engine doesn't copy exactly what we tell it to copy,
410  * we'll notice.
411  */
412 static int dmatest_func(void *data)
413 {
414 	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
415 	struct dmatest_thread	*thread = data;
416 	struct dmatest_done	done = { .wait = &done_wait };
417 	struct dmatest_info	*info;
418 	struct dmatest_params	*params;
419 	struct dma_chan		*chan;
420 	struct dma_device	*dev;
421 	unsigned int		error_count;
422 	unsigned int		failed_tests = 0;
423 	unsigned int		total_tests = 0;
424 	dma_cookie_t		cookie;
425 	enum dma_status		status;
426 	enum dma_ctrl_flags 	flags;
427 	u8			*pq_coefs = NULL;
428 	int			ret;
429 	int			src_cnt;
430 	int			dst_cnt;
431 	int			i;
432 	ktime_t			ktime, start, diff;
433 	ktime_t			filltime = 0;
434 	ktime_t			comparetime = 0;
435 	s64			runtime = 0;
436 	unsigned long long	total_len = 0;
437 	u8			align = 0;
438 
439 	set_freezable();
440 
441 	ret = -ENOMEM;
442 
443 	smp_rmb();
444 	info = thread->info;
445 	params = &info->params;
446 	chan = thread->chan;
447 	dev = chan->device;
448 	if (thread->type == DMA_MEMCPY) {
449 		align = dev->copy_align;
450 		src_cnt = dst_cnt = 1;
451 	} else if (thread->type == DMA_SG) {
452 		align = dev->copy_align;
453 		src_cnt = dst_cnt = sg_buffers;
454 	} else if (thread->type == DMA_XOR) {
455 		/* force odd to ensure dst = src */
456 		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
457 		dst_cnt = 1;
458 		align = dev->xor_align;
459 	} else if (thread->type == DMA_PQ) {
460 		/* force odd to ensure dst = src */
461 		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
462 		dst_cnt = 2;
463 		align = dev->pq_align;
464 
465 		pq_coefs = kmalloc(params->pq_sources + 1, GFP_KERNEL);
466 		if (!pq_coefs)
467 			goto err_thread_type;
468 
469 		for (i = 0; i < src_cnt; i++)
470 			pq_coefs[i] = 1;
471 	} else
472 		goto err_thread_type;
473 
474 	thread->srcs = kcalloc(src_cnt + 1, sizeof(u8 *), GFP_KERNEL);
475 	if (!thread->srcs)
476 		goto err_srcs;
477 
478 	thread->usrcs = kcalloc(src_cnt + 1, sizeof(u8 *), GFP_KERNEL);
479 	if (!thread->usrcs)
480 		goto err_usrcs;
481 
482 	for (i = 0; i < src_cnt; i++) {
483 		thread->usrcs[i] = kmalloc(params->buf_size + align,
484 					   GFP_KERNEL);
485 		if (!thread->usrcs[i])
486 			goto err_srcbuf;
487 
488 		/* align srcs to alignment restriction */
489 		if (align)
490 			thread->srcs[i] = PTR_ALIGN(thread->usrcs[i], align);
491 		else
492 			thread->srcs[i] = thread->usrcs[i];
493 	}
494 	thread->srcs[i] = NULL;
495 
496 	thread->dsts = kcalloc(dst_cnt + 1, sizeof(u8 *), GFP_KERNEL);
497 	if (!thread->dsts)
498 		goto err_dsts;
499 
500 	thread->udsts = kcalloc(dst_cnt + 1, sizeof(u8 *), GFP_KERNEL);
501 	if (!thread->udsts)
502 		goto err_udsts;
503 
504 	for (i = 0; i < dst_cnt; i++) {
505 		thread->udsts[i] = kmalloc(params->buf_size + align,
506 					   GFP_KERNEL);
507 		if (!thread->udsts[i])
508 			goto err_dstbuf;
509 
510 		/* align dsts to alignment restriction */
511 		if (align)
512 			thread->dsts[i] = PTR_ALIGN(thread->udsts[i], align);
513 		else
514 			thread->dsts[i] = thread->udsts[i];
515 	}
516 	thread->dsts[i] = NULL;
517 
518 	set_user_nice(current, 10);
519 
520 	/*
521 	 * src and dst buffers are freed by ourselves below
522 	 */
523 	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
524 
525 	ktime = ktime_get();
526 	while (!kthread_should_stop()
527 	       && !(params->iterations && total_tests >= params->iterations)) {
528 		struct dma_async_tx_descriptor *tx = NULL;
529 		struct dmaengine_unmap_data *um;
530 		dma_addr_t srcs[src_cnt];
531 		dma_addr_t *dsts;
532 		unsigned int src_off, dst_off, len;
533 		struct scatterlist tx_sg[src_cnt];
534 		struct scatterlist rx_sg[src_cnt];
535 
536 		total_tests++;
537 
538 		if (1 << align > params->buf_size) {
539 			pr_err("%u-byte buffer too small for %d-byte alignment\n",
540 			       params->buf_size, 1 << align);
541 			break;
542 		}
543 
544 		if (params->noverify)
545 			len = params->buf_size;
546 		else
547 			len = dmatest_random() % params->buf_size + 1;
548 
549 		len = (len >> align) << align;
550 		if (!len)
551 			len = 1 << align;
552 
553 		total_len += len;
554 
555 		if (params->noverify) {
556 			src_off = 0;
557 			dst_off = 0;
558 		} else {
559 			start = ktime_get();
560 			src_off = dmatest_random() % (params->buf_size - len + 1);
561 			dst_off = dmatest_random() % (params->buf_size - len + 1);
562 
563 			src_off = (src_off >> align) << align;
564 			dst_off = (dst_off >> align) << align;
565 
566 			dmatest_init_srcs(thread->srcs, src_off, len,
567 					  params->buf_size);
568 			dmatest_init_dsts(thread->dsts, dst_off, len,
569 					  params->buf_size);
570 
571 			diff = ktime_sub(ktime_get(), start);
572 			filltime = ktime_add(filltime, diff);
573 		}
574 
575 		um = dmaengine_get_unmap_data(dev->dev, src_cnt + dst_cnt,
576 					      GFP_KERNEL);
577 		if (!um) {
578 			failed_tests++;
579 			result("unmap data NULL", total_tests,
580 			       src_off, dst_off, len, ret);
581 			continue;
582 		}
583 
584 		um->len = params->buf_size;
585 		for (i = 0; i < src_cnt; i++) {
586 			void *buf = thread->srcs[i];
587 			struct page *pg = virt_to_page(buf);
588 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
589 
590 			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
591 						   um->len, DMA_TO_DEVICE);
592 			srcs[i] = um->addr[i] + src_off;
593 			ret = dma_mapping_error(dev->dev, um->addr[i]);
594 			if (ret) {
595 				dmaengine_unmap_put(um);
596 				result("src mapping error", total_tests,
597 				       src_off, dst_off, len, ret);
598 				failed_tests++;
599 				continue;
600 			}
601 			um->to_cnt++;
602 		}
603 		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
604 		dsts = &um->addr[src_cnt];
605 		for (i = 0; i < dst_cnt; i++) {
606 			void *buf = thread->dsts[i];
607 			struct page *pg = virt_to_page(buf);
608 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
609 
610 			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
611 					       DMA_BIDIRECTIONAL);
612 			ret = dma_mapping_error(dev->dev, dsts[i]);
613 			if (ret) {
614 				dmaengine_unmap_put(um);
615 				result("dst mapping error", total_tests,
616 				       src_off, dst_off, len, ret);
617 				failed_tests++;
618 				continue;
619 			}
620 			um->bidi_cnt++;
621 		}
622 
623 		sg_init_table(tx_sg, src_cnt);
624 		sg_init_table(rx_sg, src_cnt);
625 		for (i = 0; i < src_cnt; i++) {
626 			sg_dma_address(&rx_sg[i]) = srcs[i];
627 			sg_dma_address(&tx_sg[i]) = dsts[i] + dst_off;
628 			sg_dma_len(&tx_sg[i]) = len;
629 			sg_dma_len(&rx_sg[i]) = len;
630 		}
631 
632 		if (thread->type == DMA_MEMCPY)
633 			tx = dev->device_prep_dma_memcpy(chan,
634 							 dsts[0] + dst_off,
635 							 srcs[0], len, flags);
636 		else if (thread->type == DMA_SG)
637 			tx = dev->device_prep_dma_sg(chan, tx_sg, src_cnt,
638 						     rx_sg, src_cnt, flags);
639 		else if (thread->type == DMA_XOR)
640 			tx = dev->device_prep_dma_xor(chan,
641 						      dsts[0] + dst_off,
642 						      srcs, src_cnt,
643 						      len, flags);
644 		else if (thread->type == DMA_PQ) {
645 			dma_addr_t dma_pq[dst_cnt];
646 
647 			for (i = 0; i < dst_cnt; i++)
648 				dma_pq[i] = dsts[i] + dst_off;
649 			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
650 						     src_cnt, pq_coefs,
651 						     len, flags);
652 		}
653 
654 		if (!tx) {
655 			dmaengine_unmap_put(um);
656 			result("prep error", total_tests, src_off,
657 			       dst_off, len, ret);
658 			msleep(100);
659 			failed_tests++;
660 			continue;
661 		}
662 
663 		done.done = false;
664 		tx->callback = dmatest_callback;
665 		tx->callback_param = &done;
666 		cookie = tx->tx_submit(tx);
667 
668 		if (dma_submit_error(cookie)) {
669 			dmaengine_unmap_put(um);
670 			result("submit error", total_tests, src_off,
671 			       dst_off, len, ret);
672 			msleep(100);
673 			failed_tests++;
674 			continue;
675 		}
676 		dma_async_issue_pending(chan);
677 
678 		wait_event_freezable_timeout(done_wait, done.done,
679 					     msecs_to_jiffies(params->timeout));
680 
681 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
682 
683 		if (!done.done) {
684 			/*
685 			 * We're leaving the timed out dma operation with
686 			 * dangling pointer to done_wait.  To make this
687 			 * correct, we'll need to allocate wait_done for
688 			 * each test iteration and perform "who's gonna
689 			 * free it this time?" dancing.  For now, just
690 			 * leave it dangling.
691 			 */
692 			dmaengine_unmap_put(um);
693 			result("test timed out", total_tests, src_off, dst_off,
694 			       len, 0);
695 			failed_tests++;
696 			continue;
697 		} else if (status != DMA_COMPLETE) {
698 			dmaengine_unmap_put(um);
699 			result(status == DMA_ERROR ?
700 			       "completion error status" :
701 			       "completion busy status", total_tests, src_off,
702 			       dst_off, len, ret);
703 			failed_tests++;
704 			continue;
705 		}
706 
707 		dmaengine_unmap_put(um);
708 
709 		if (params->noverify) {
710 			verbose_result("test passed", total_tests, src_off,
711 				       dst_off, len, 0);
712 			continue;
713 		}
714 
715 		start = ktime_get();
716 		pr_debug("%s: verifying source buffer...\n", current->comm);
717 		error_count = dmatest_verify(thread->srcs, 0, src_off,
718 				0, PATTERN_SRC, true);
719 		error_count += dmatest_verify(thread->srcs, src_off,
720 				src_off + len, src_off,
721 				PATTERN_SRC | PATTERN_COPY, true);
722 		error_count += dmatest_verify(thread->srcs, src_off + len,
723 				params->buf_size, src_off + len,
724 				PATTERN_SRC, true);
725 
726 		pr_debug("%s: verifying dest buffer...\n", current->comm);
727 		error_count += dmatest_verify(thread->dsts, 0, dst_off,
728 				0, PATTERN_DST, false);
729 		error_count += dmatest_verify(thread->dsts, dst_off,
730 				dst_off + len, src_off,
731 				PATTERN_SRC | PATTERN_COPY, false);
732 		error_count += dmatest_verify(thread->dsts, dst_off + len,
733 				params->buf_size, dst_off + len,
734 				PATTERN_DST, false);
735 
736 		diff = ktime_sub(ktime_get(), start);
737 		comparetime = ktime_add(comparetime, diff);
738 
739 		if (error_count) {
740 			result("data error", total_tests, src_off, dst_off,
741 			       len, error_count);
742 			failed_tests++;
743 		} else {
744 			verbose_result("test passed", total_tests, src_off,
745 				       dst_off, len, 0);
746 		}
747 	}
748 	ktime = ktime_sub(ktime_get(), ktime);
749 	ktime = ktime_sub(ktime, comparetime);
750 	ktime = ktime_sub(ktime, filltime);
751 	runtime = ktime_to_us(ktime);
752 
753 	ret = 0;
754 err_dstbuf:
755 	for (i = 0; thread->udsts[i]; i++)
756 		kfree(thread->udsts[i]);
757 	kfree(thread->udsts);
758 err_udsts:
759 	kfree(thread->dsts);
760 err_dsts:
761 err_srcbuf:
762 	for (i = 0; thread->usrcs[i]; i++)
763 		kfree(thread->usrcs[i]);
764 	kfree(thread->usrcs);
765 err_usrcs:
766 	kfree(thread->srcs);
767 err_srcs:
768 	kfree(pq_coefs);
769 err_thread_type:
770 	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
771 		current->comm, total_tests, failed_tests,
772 		dmatest_persec(runtime, total_tests),
773 		dmatest_KBs(runtime, total_len), ret);
774 
775 	/* terminate all transfers on specified channels */
776 	if (ret)
777 		dmaengine_terminate_all(chan);
778 
779 	thread->done = true;
780 	wake_up(&thread_wait);
781 
782 	return ret;
783 }
784 
785 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
786 {
787 	struct dmatest_thread	*thread;
788 	struct dmatest_thread	*_thread;
789 	int			ret;
790 
791 	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
792 		ret = kthread_stop(thread->task);
793 		pr_debug("thread %s exited with status %d\n",
794 			 thread->task->comm, ret);
795 		list_del(&thread->node);
796 		put_task_struct(thread->task);
797 		kfree(thread);
798 	}
799 
800 	/* terminate all transfers on specified channels */
801 	dmaengine_terminate_all(dtc->chan);
802 
803 	kfree(dtc);
804 }
805 
806 static int dmatest_add_threads(struct dmatest_info *info,
807 		struct dmatest_chan *dtc, enum dma_transaction_type type)
808 {
809 	struct dmatest_params *params = &info->params;
810 	struct dmatest_thread *thread;
811 	struct dma_chan *chan = dtc->chan;
812 	char *op;
813 	unsigned int i;
814 
815 	if (type == DMA_MEMCPY)
816 		op = "copy";
817 	else if (type == DMA_SG)
818 		op = "sg";
819 	else if (type == DMA_XOR)
820 		op = "xor";
821 	else if (type == DMA_PQ)
822 		op = "pq";
823 	else
824 		return -EINVAL;
825 
826 	for (i = 0; i < params->threads_per_chan; i++) {
827 		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
828 		if (!thread) {
829 			pr_warn("No memory for %s-%s%u\n",
830 				dma_chan_name(chan), op, i);
831 			break;
832 		}
833 		thread->info = info;
834 		thread->chan = dtc->chan;
835 		thread->type = type;
836 		smp_wmb();
837 		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
838 				dma_chan_name(chan), op, i);
839 		if (IS_ERR(thread->task)) {
840 			pr_warn("Failed to create thread %s-%s%u\n",
841 				dma_chan_name(chan), op, i);
842 			kfree(thread);
843 			break;
844 		}
845 
846 		/* srcbuf and dstbuf are allocated by the thread itself */
847 		get_task_struct(thread->task);
848 		list_add_tail(&thread->node, &dtc->threads);
849 		wake_up_process(thread->task);
850 	}
851 
852 	return i;
853 }
854 
855 static int dmatest_add_channel(struct dmatest_info *info,
856 		struct dma_chan *chan)
857 {
858 	struct dmatest_chan	*dtc;
859 	struct dma_device	*dma_dev = chan->device;
860 	unsigned int		thread_count = 0;
861 	int cnt;
862 
863 	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
864 	if (!dtc) {
865 		pr_warn("No memory for %s\n", dma_chan_name(chan));
866 		return -ENOMEM;
867 	}
868 
869 	dtc->chan = chan;
870 	INIT_LIST_HEAD(&dtc->threads);
871 
872 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
873 		if (dmatest == 0) {
874 			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
875 			thread_count += cnt > 0 ? cnt : 0;
876 		}
877 	}
878 
879 	if (dma_has_cap(DMA_SG, dma_dev->cap_mask)) {
880 		if (dmatest == 1) {
881 			cnt = dmatest_add_threads(info, dtc, DMA_SG);
882 			thread_count += cnt > 0 ? cnt : 0;
883 		}
884 	}
885 
886 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
887 		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
888 		thread_count += cnt > 0 ? cnt : 0;
889 	}
890 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
891 		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
892 		thread_count += cnt > 0 ? cnt : 0;
893 	}
894 
895 	pr_info("Started %u threads using %s\n",
896 		thread_count, dma_chan_name(chan));
897 
898 	list_add_tail(&dtc->node, &info->channels);
899 	info->nr_channels++;
900 
901 	return 0;
902 }
903 
904 static bool filter(struct dma_chan *chan, void *param)
905 {
906 	struct dmatest_params *params = param;
907 
908 	if (!dmatest_match_channel(params, chan) ||
909 	    !dmatest_match_device(params, chan->device))
910 		return false;
911 	else
912 		return true;
913 }
914 
915 static void request_channels(struct dmatest_info *info,
916 			     enum dma_transaction_type type)
917 {
918 	dma_cap_mask_t mask;
919 
920 	dma_cap_zero(mask);
921 	dma_cap_set(type, mask);
922 	for (;;) {
923 		struct dmatest_params *params = &info->params;
924 		struct dma_chan *chan;
925 
926 		chan = dma_request_channel(mask, filter, params);
927 		if (chan) {
928 			if (dmatest_add_channel(info, chan)) {
929 				dma_release_channel(chan);
930 				break; /* add_channel failed, punt */
931 			}
932 		} else
933 			break; /* no more channels available */
934 		if (params->max_channels &&
935 		    info->nr_channels >= params->max_channels)
936 			break; /* we have all we need */
937 	}
938 }
939 
940 static void run_threaded_test(struct dmatest_info *info)
941 {
942 	struct dmatest_params *params = &info->params;
943 
944 	/* Copy test parameters */
945 	params->buf_size = test_buf_size;
946 	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
947 	strlcpy(params->device, strim(test_device), sizeof(params->device));
948 	params->threads_per_chan = threads_per_chan;
949 	params->max_channels = max_channels;
950 	params->iterations = iterations;
951 	params->xor_sources = xor_sources;
952 	params->pq_sources = pq_sources;
953 	params->timeout = timeout;
954 	params->noverify = noverify;
955 
956 	request_channels(info, DMA_MEMCPY);
957 	request_channels(info, DMA_XOR);
958 	request_channels(info, DMA_SG);
959 	request_channels(info, DMA_PQ);
960 }
961 
962 static void stop_threaded_test(struct dmatest_info *info)
963 {
964 	struct dmatest_chan *dtc, *_dtc;
965 	struct dma_chan *chan;
966 
967 	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
968 		list_del(&dtc->node);
969 		chan = dtc->chan;
970 		dmatest_cleanup_channel(dtc);
971 		pr_debug("dropped channel %s\n", dma_chan_name(chan));
972 		dma_release_channel(chan);
973 	}
974 
975 	info->nr_channels = 0;
976 }
977 
978 static void restart_threaded_test(struct dmatest_info *info, bool run)
979 {
980 	/* we might be called early to set run=, defer running until all
981 	 * parameters have been evaluated
982 	 */
983 	if (!info->did_init)
984 		return;
985 
986 	/* Stop any running test first */
987 	stop_threaded_test(info);
988 
989 	/* Run test with new parameters */
990 	run_threaded_test(info);
991 }
992 
993 static int dmatest_run_get(char *val, const struct kernel_param *kp)
994 {
995 	struct dmatest_info *info = &test_info;
996 
997 	mutex_lock(&info->lock);
998 	if (is_threaded_test_run(info)) {
999 		dmatest_run = true;
1000 	} else {
1001 		stop_threaded_test(info);
1002 		dmatest_run = false;
1003 	}
1004 	mutex_unlock(&info->lock);
1005 
1006 	return param_get_bool(val, kp);
1007 }
1008 
1009 static int dmatest_run_set(const char *val, const struct kernel_param *kp)
1010 {
1011 	struct dmatest_info *info = &test_info;
1012 	int ret;
1013 
1014 	mutex_lock(&info->lock);
1015 	ret = param_set_bool(val, kp);
1016 	if (ret) {
1017 		mutex_unlock(&info->lock);
1018 		return ret;
1019 	}
1020 
1021 	if (is_threaded_test_run(info))
1022 		ret = -EBUSY;
1023 	else if (dmatest_run)
1024 		restart_threaded_test(info, dmatest_run);
1025 
1026 	mutex_unlock(&info->lock);
1027 
1028 	return ret;
1029 }
1030 
1031 static int __init dmatest_init(void)
1032 {
1033 	struct dmatest_info *info = &test_info;
1034 	struct dmatest_params *params = &info->params;
1035 
1036 	if (dmatest_run) {
1037 		mutex_lock(&info->lock);
1038 		run_threaded_test(info);
1039 		mutex_unlock(&info->lock);
1040 	}
1041 
1042 	if (params->iterations && wait)
1043 		wait_event(thread_wait, !is_threaded_test_run(info));
1044 
1045 	/* module parameters are stable, inittime tests are started,
1046 	 * let userspace take over 'run' control
1047 	 */
1048 	info->did_init = true;
1049 
1050 	return 0;
1051 }
1052 /* when compiled-in wait for drivers to load first */
1053 late_initcall(dmatest_init);
1054 
1055 static void __exit dmatest_exit(void)
1056 {
1057 	struct dmatest_info *info = &test_info;
1058 
1059 	mutex_lock(&info->lock);
1060 	stop_threaded_test(info);
1061 	mutex_unlock(&info->lock);
1062 }
1063 module_exit(dmatest_exit);
1064 
1065 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1066 MODULE_LICENSE("GPL v2");
1067