xref: /openbmc/linux/drivers/dma/dmatest.c (revision 24b1944f)
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 #include <linux/delay.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmaengine.h>
14 #include <linux/freezer.h>
15 #include <linux/init.h>
16 #include <linux/kthread.h>
17 #include <linux/module.h>
18 #include <linux/moduleparam.h>
19 #include <linux/random.h>
20 #include <linux/slab.h>
21 #include <linux/wait.h>
22 #include <linux/ctype.h>
23 #include <linux/debugfs.h>
24 #include <linux/uaccess.h>
25 #include <linux/seq_file.h>
26 
27 static unsigned int test_buf_size = 16384;
28 module_param(test_buf_size, uint, S_IRUGO);
29 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
30 
31 static char test_channel[20];
32 module_param_string(channel, test_channel, sizeof(test_channel), S_IRUGO);
33 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
34 
35 static char test_device[20];
36 module_param_string(device, test_device, sizeof(test_device), S_IRUGO);
37 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
38 
39 static unsigned int threads_per_chan = 1;
40 module_param(threads_per_chan, uint, S_IRUGO);
41 MODULE_PARM_DESC(threads_per_chan,
42 		"Number of threads to start per channel (default: 1)");
43 
44 static unsigned int max_channels;
45 module_param(max_channels, uint, S_IRUGO);
46 MODULE_PARM_DESC(max_channels,
47 		"Maximum number of channels to use (default: all)");
48 
49 static unsigned int iterations;
50 module_param(iterations, uint, S_IRUGO);
51 MODULE_PARM_DESC(iterations,
52 		"Iterations before stopping test (default: infinite)");
53 
54 static unsigned int xor_sources = 3;
55 module_param(xor_sources, uint, S_IRUGO);
56 MODULE_PARM_DESC(xor_sources,
57 		"Number of xor source buffers (default: 3)");
58 
59 static unsigned int pq_sources = 3;
60 module_param(pq_sources, uint, S_IRUGO);
61 MODULE_PARM_DESC(pq_sources,
62 		"Number of p+q source buffers (default: 3)");
63 
64 static int timeout = 3000;
65 module_param(timeout, uint, S_IRUGO);
66 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
67 		 "Pass -1 for infinite timeout");
68 
69 /* Maximum amount of mismatched bytes in buffer to print */
70 #define MAX_ERROR_COUNT		32
71 
72 /*
73  * Initialization patterns. All bytes in the source buffer has bit 7
74  * set, all bytes in the destination buffer has bit 7 cleared.
75  *
76  * Bit 6 is set for all bytes which are to be copied by the DMA
77  * engine. Bit 5 is set for all bytes which are to be overwritten by
78  * the DMA engine.
79  *
80  * The remaining bits are the inverse of a counter which increments by
81  * one for each byte address.
82  */
83 #define PATTERN_SRC		0x80
84 #define PATTERN_DST		0x00
85 #define PATTERN_COPY		0x40
86 #define PATTERN_OVERWRITE	0x20
87 #define PATTERN_COUNT_MASK	0x1f
88 
89 enum dmatest_error_type {
90 	DMATEST_ET_OK,
91 	DMATEST_ET_MAP_SRC,
92 	DMATEST_ET_MAP_DST,
93 	DMATEST_ET_PREP,
94 	DMATEST_ET_SUBMIT,
95 	DMATEST_ET_TIMEOUT,
96 	DMATEST_ET_DMA_ERROR,
97 	DMATEST_ET_DMA_IN_PROGRESS,
98 	DMATEST_ET_VERIFY,
99 	DMATEST_ET_VERIFY_BUF,
100 };
101 
102 struct dmatest_verify_buffer {
103 	unsigned int	index;
104 	u8		expected;
105 	u8		actual;
106 };
107 
108 struct dmatest_verify_result {
109 	unsigned int			error_count;
110 	struct dmatest_verify_buffer	data[MAX_ERROR_COUNT];
111 	u8				pattern;
112 	bool				is_srcbuf;
113 };
114 
115 struct dmatest_thread_result {
116 	struct list_head	node;
117 	unsigned int		n;
118 	unsigned int		src_off;
119 	unsigned int		dst_off;
120 	unsigned int		len;
121 	enum dmatest_error_type	type;
122 	union {
123 		unsigned long			data;
124 		dma_cookie_t			cookie;
125 		enum dma_status			status;
126 		int				error;
127 		struct dmatest_verify_result	*vr;
128 	};
129 };
130 
131 struct dmatest_result {
132 	struct list_head	node;
133 	char			*name;
134 	struct list_head	results;
135 };
136 
137 struct dmatest_info;
138 
139 struct dmatest_thread {
140 	struct list_head	node;
141 	struct dmatest_info	*info;
142 	struct task_struct	*task;
143 	struct dma_chan		*chan;
144 	u8			**srcs;
145 	u8			**dsts;
146 	enum dma_transaction_type type;
147 	bool			done;
148 };
149 
150 struct dmatest_chan {
151 	struct list_head	node;
152 	struct dma_chan		*chan;
153 	struct list_head	threads;
154 };
155 
156 /**
157  * struct dmatest_params - test parameters.
158  * @buf_size:		size of the memcpy test buffer
159  * @channel:		bus ID of the channel to test
160  * @device:		bus ID of the DMA Engine to test
161  * @threads_per_chan:	number of threads to start per channel
162  * @max_channels:	maximum number of channels to use
163  * @iterations:		iterations before stopping test
164  * @xor_sources:	number of xor source buffers
165  * @pq_sources:		number of p+q source buffers
166  * @timeout:		transfer timeout in msec, -1 for infinite timeout
167  */
168 struct dmatest_params {
169 	unsigned int	buf_size;
170 	char		channel[20];
171 	char		device[20];
172 	unsigned int	threads_per_chan;
173 	unsigned int	max_channels;
174 	unsigned int	iterations;
175 	unsigned int	xor_sources;
176 	unsigned int	pq_sources;
177 	int		timeout;
178 };
179 
180 /**
181  * struct dmatest_info - test information.
182  * @params:		test parameters
183  * @lock:		access protection to the fields of this structure
184  */
185 struct dmatest_info {
186 	/* Test parameters */
187 	struct dmatest_params	params;
188 
189 	/* Internal state */
190 	struct list_head	channels;
191 	unsigned int		nr_channels;
192 	struct mutex		lock;
193 
194 	/* debugfs related stuff */
195 	struct dentry		*root;
196 	struct dmatest_params	dbgfs_params;
197 
198 	/* Test results */
199 	struct list_head	results;
200 	struct mutex		results_lock;
201 };
202 
203 static struct dmatest_info test_info;
204 
205 static bool dmatest_match_channel(struct dmatest_params *params,
206 		struct dma_chan *chan)
207 {
208 	if (params->channel[0] == '\0')
209 		return true;
210 	return strcmp(dma_chan_name(chan), params->channel) == 0;
211 }
212 
213 static bool dmatest_match_device(struct dmatest_params *params,
214 		struct dma_device *device)
215 {
216 	if (params->device[0] == '\0')
217 		return true;
218 	return strcmp(dev_name(device->dev), params->device) == 0;
219 }
220 
221 static unsigned long dmatest_random(void)
222 {
223 	unsigned long buf;
224 
225 	get_random_bytes(&buf, sizeof(buf));
226 	return buf;
227 }
228 
229 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
230 		unsigned int buf_size)
231 {
232 	unsigned int i;
233 	u8 *buf;
234 
235 	for (; (buf = *bufs); bufs++) {
236 		for (i = 0; i < start; i++)
237 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
238 		for ( ; i < start + len; i++)
239 			buf[i] = PATTERN_SRC | PATTERN_COPY
240 				| (~i & PATTERN_COUNT_MASK);
241 		for ( ; i < buf_size; i++)
242 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
243 		buf++;
244 	}
245 }
246 
247 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
248 		unsigned int buf_size)
249 {
250 	unsigned int i;
251 	u8 *buf;
252 
253 	for (; (buf = *bufs); bufs++) {
254 		for (i = 0; i < start; i++)
255 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
256 		for ( ; i < start + len; i++)
257 			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
258 				| (~i & PATTERN_COUNT_MASK);
259 		for ( ; i < buf_size; i++)
260 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
261 	}
262 }
263 
264 static unsigned int dmatest_verify(struct dmatest_verify_result *vr, u8 **bufs,
265 		unsigned int start, unsigned int end, unsigned int counter,
266 		u8 pattern, bool is_srcbuf)
267 {
268 	unsigned int i;
269 	unsigned int error_count = 0;
270 	u8 actual;
271 	u8 expected;
272 	u8 *buf;
273 	unsigned int counter_orig = counter;
274 	struct dmatest_verify_buffer *vb;
275 
276 	for (; (buf = *bufs); bufs++) {
277 		counter = counter_orig;
278 		for (i = start; i < end; i++) {
279 			actual = buf[i];
280 			expected = pattern | (~counter & PATTERN_COUNT_MASK);
281 			if (actual != expected) {
282 				if (error_count < MAX_ERROR_COUNT && vr) {
283 					vb = &vr->data[error_count];
284 					vb->index = i;
285 					vb->expected = expected;
286 					vb->actual = actual;
287 				}
288 				error_count++;
289 			}
290 			counter++;
291 		}
292 	}
293 
294 	if (error_count > MAX_ERROR_COUNT)
295 		pr_warning("%s: %u errors suppressed\n",
296 			current->comm, error_count - MAX_ERROR_COUNT);
297 
298 	return error_count;
299 }
300 
301 /* poor man's completion - we want to use wait_event_freezable() on it */
302 struct dmatest_done {
303 	bool			done;
304 	wait_queue_head_t	*wait;
305 };
306 
307 static void dmatest_callback(void *arg)
308 {
309 	struct dmatest_done *done = arg;
310 
311 	done->done = true;
312 	wake_up_all(done->wait);
313 }
314 
315 static inline void unmap_src(struct device *dev, dma_addr_t *addr, size_t len,
316 			     unsigned int count)
317 {
318 	while (count--)
319 		dma_unmap_single(dev, addr[count], len, DMA_TO_DEVICE);
320 }
321 
322 static inline void unmap_dst(struct device *dev, dma_addr_t *addr, size_t len,
323 			     unsigned int count)
324 {
325 	while (count--)
326 		dma_unmap_single(dev, addr[count], len, DMA_BIDIRECTIONAL);
327 }
328 
329 static unsigned int min_odd(unsigned int x, unsigned int y)
330 {
331 	unsigned int val = min(x, y);
332 
333 	return val % 2 ? val : val - 1;
334 }
335 
336 static char *verify_result_get_one(struct dmatest_verify_result *vr,
337 		unsigned int i)
338 {
339 	struct dmatest_verify_buffer *vb = &vr->data[i];
340 	u8 diff = vb->actual ^ vr->pattern;
341 	static char buf[512];
342 	char *msg;
343 
344 	if (vr->is_srcbuf)
345 		msg = "srcbuf overwritten!";
346 	else if ((vr->pattern & PATTERN_COPY)
347 			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
348 		msg = "dstbuf not copied!";
349 	else if (diff & PATTERN_SRC)
350 		msg = "dstbuf was copied!";
351 	else
352 		msg = "dstbuf mismatch!";
353 
354 	snprintf(buf, sizeof(buf) - 1, "%s [0x%x] Expected %02x, got %02x", msg,
355 		 vb->index, vb->expected, vb->actual);
356 
357 	return buf;
358 }
359 
360 static char *thread_result_get(const char *name,
361 		struct dmatest_thread_result *tr)
362 {
363 	static const char * const messages[] = {
364 		[DMATEST_ET_OK]			= "No errors",
365 		[DMATEST_ET_MAP_SRC]		= "src mapping error",
366 		[DMATEST_ET_MAP_DST]		= "dst mapping error",
367 		[DMATEST_ET_PREP]		= "prep error",
368 		[DMATEST_ET_SUBMIT]		= "submit error",
369 		[DMATEST_ET_TIMEOUT]		= "test timed out",
370 		[DMATEST_ET_DMA_ERROR]		=
371 			"got completion callback (DMA_ERROR)",
372 		[DMATEST_ET_DMA_IN_PROGRESS]	=
373 			"got completion callback (DMA_IN_PROGRESS)",
374 		[DMATEST_ET_VERIFY]		= "errors",
375 		[DMATEST_ET_VERIFY_BUF]		= "verify errors",
376 	};
377 	static char buf[512];
378 
379 	snprintf(buf, sizeof(buf) - 1,
380 		 "%s: #%u: %s with src_off=0x%x ""dst_off=0x%x len=0x%x (%lu)",
381 		 name, tr->n, messages[tr->type], tr->src_off, tr->dst_off,
382 		 tr->len, tr->data);
383 
384 	return buf;
385 }
386 
387 static int thread_result_add(struct dmatest_info *info,
388 		struct dmatest_result *r, enum dmatest_error_type type,
389 		unsigned int n, unsigned int src_off, unsigned int dst_off,
390 		unsigned int len, unsigned long data)
391 {
392 	struct dmatest_thread_result *tr;
393 
394 	tr = kzalloc(sizeof(*tr), GFP_KERNEL);
395 	if (!tr)
396 		return -ENOMEM;
397 
398 	tr->type = type;
399 	tr->n = n;
400 	tr->src_off = src_off;
401 	tr->dst_off = dst_off;
402 	tr->len = len;
403 	tr->data = data;
404 
405 	mutex_lock(&info->results_lock);
406 	list_add_tail(&tr->node, &r->results);
407 	mutex_unlock(&info->results_lock);
408 
409 	pr_warn("%s\n", thread_result_get(r->name, tr));
410 	return 0;
411 }
412 
413 static unsigned int verify_result_add(struct dmatest_info *info,
414 		struct dmatest_result *r, unsigned int n,
415 		unsigned int src_off, unsigned int dst_off, unsigned int len,
416 		u8 **bufs, int whence, unsigned int counter, u8 pattern,
417 		bool is_srcbuf)
418 {
419 	struct dmatest_verify_result *vr;
420 	unsigned int error_count;
421 	unsigned int buf_off = is_srcbuf ? src_off : dst_off;
422 	unsigned int start, end;
423 
424 	if (whence < 0) {
425 		start = 0;
426 		end = buf_off;
427 	} else if (whence > 0) {
428 		start = buf_off + len;
429 		end = info->params.buf_size;
430 	} else {
431 		start = buf_off;
432 		end = buf_off + len;
433 	}
434 
435 	vr = kmalloc(sizeof(*vr), GFP_KERNEL);
436 	if (!vr) {
437 		pr_warn("dmatest: No memory to store verify result\n");
438 		return dmatest_verify(NULL, bufs, start, end, counter, pattern,
439 				      is_srcbuf);
440 	}
441 
442 	vr->pattern = pattern;
443 	vr->is_srcbuf = is_srcbuf;
444 
445 	error_count = dmatest_verify(vr, bufs, start, end, counter, pattern,
446 				     is_srcbuf);
447 	if (error_count) {
448 		vr->error_count = error_count;
449 		thread_result_add(info, r, DMATEST_ET_VERIFY_BUF, n, src_off,
450 				  dst_off, len, (unsigned long)vr);
451 		return error_count;
452 	}
453 
454 	kfree(vr);
455 	return 0;
456 }
457 
458 static void result_free(struct dmatest_info *info, const char *name)
459 {
460 	struct dmatest_result *r, *_r;
461 
462 	mutex_lock(&info->results_lock);
463 	list_for_each_entry_safe(r, _r, &info->results, node) {
464 		struct dmatest_thread_result *tr, *_tr;
465 
466 		if (name && strcmp(r->name, name))
467 			continue;
468 
469 		list_for_each_entry_safe(tr, _tr, &r->results, node) {
470 			if (tr->type == DMATEST_ET_VERIFY_BUF)
471 				kfree(tr->vr);
472 			list_del(&tr->node);
473 			kfree(tr);
474 		}
475 
476 		kfree(r->name);
477 		list_del(&r->node);
478 		kfree(r);
479 	}
480 
481 	mutex_unlock(&info->results_lock);
482 }
483 
484 static struct dmatest_result *result_init(struct dmatest_info *info,
485 		const char *name)
486 {
487 	struct dmatest_result *r;
488 
489 	r = kzalloc(sizeof(*r), GFP_KERNEL);
490 	if (r) {
491 		r->name = kstrdup(name, GFP_KERNEL);
492 		INIT_LIST_HEAD(&r->results);
493 		mutex_lock(&info->results_lock);
494 		list_add_tail(&r->node, &info->results);
495 		mutex_unlock(&info->results_lock);
496 	}
497 	return r;
498 }
499 
500 /*
501  * This function repeatedly tests DMA transfers of various lengths and
502  * offsets for a given operation type until it is told to exit by
503  * kthread_stop(). There may be multiple threads running this function
504  * in parallel for a single channel, and there may be multiple channels
505  * being tested in parallel.
506  *
507  * Before each test, the source and destination buffer is initialized
508  * with a known pattern. This pattern is different depending on
509  * whether it's in an area which is supposed to be copied or
510  * overwritten, and different in the source and destination buffers.
511  * So if the DMA engine doesn't copy exactly what we tell it to copy,
512  * we'll notice.
513  */
514 static int dmatest_func(void *data)
515 {
516 	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
517 	struct dmatest_thread	*thread = data;
518 	struct dmatest_done	done = { .wait = &done_wait };
519 	struct dmatest_info	*info;
520 	struct dmatest_params	*params;
521 	struct dma_chan		*chan;
522 	struct dma_device	*dev;
523 	const char		*thread_name;
524 	unsigned int		src_off, dst_off, len;
525 	unsigned int		error_count;
526 	unsigned int		failed_tests = 0;
527 	unsigned int		total_tests = 0;
528 	dma_cookie_t		cookie;
529 	enum dma_status		status;
530 	enum dma_ctrl_flags 	flags;
531 	u8			*pq_coefs = NULL;
532 	int			ret;
533 	int			src_cnt;
534 	int			dst_cnt;
535 	int			i;
536 	struct dmatest_result	*result;
537 
538 	thread_name = current->comm;
539 	set_freezable();
540 
541 	ret = -ENOMEM;
542 
543 	smp_rmb();
544 	info = thread->info;
545 	params = &info->params;
546 	chan = thread->chan;
547 	dev = chan->device;
548 	if (thread->type == DMA_MEMCPY)
549 		src_cnt = dst_cnt = 1;
550 	else if (thread->type == DMA_XOR) {
551 		/* force odd to ensure dst = src */
552 		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
553 		dst_cnt = 1;
554 	} else if (thread->type == DMA_PQ) {
555 		/* force odd to ensure dst = src */
556 		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
557 		dst_cnt = 2;
558 
559 		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
560 		if (!pq_coefs)
561 			goto err_thread_type;
562 
563 		for (i = 0; i < src_cnt; i++)
564 			pq_coefs[i] = 1;
565 	} else
566 		goto err_thread_type;
567 
568 	result = result_init(info, thread_name);
569 	if (!result)
570 		goto err_srcs;
571 
572 	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
573 	if (!thread->srcs)
574 		goto err_srcs;
575 	for (i = 0; i < src_cnt; i++) {
576 		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
577 		if (!thread->srcs[i])
578 			goto err_srcbuf;
579 	}
580 	thread->srcs[i] = NULL;
581 
582 	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
583 	if (!thread->dsts)
584 		goto err_dsts;
585 	for (i = 0; i < dst_cnt; i++) {
586 		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
587 		if (!thread->dsts[i])
588 			goto err_dstbuf;
589 	}
590 	thread->dsts[i] = NULL;
591 
592 	set_user_nice(current, 10);
593 
594 	/*
595 	 * src buffers are freed by the DMAEngine code with dma_unmap_single()
596 	 * dst buffers are freed by ourselves below
597 	 */
598 	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT
599 	      | DMA_COMPL_SKIP_DEST_UNMAP | DMA_COMPL_SRC_UNMAP_SINGLE;
600 
601 	while (!kthread_should_stop()
602 	       && !(params->iterations && total_tests >= params->iterations)) {
603 		struct dma_async_tx_descriptor *tx = NULL;
604 		dma_addr_t dma_srcs[src_cnt];
605 		dma_addr_t dma_dsts[dst_cnt];
606 		u8 align = 0;
607 
608 		total_tests++;
609 
610 		/* honor alignment restrictions */
611 		if (thread->type == DMA_MEMCPY)
612 			align = dev->copy_align;
613 		else if (thread->type == DMA_XOR)
614 			align = dev->xor_align;
615 		else if (thread->type == DMA_PQ)
616 			align = dev->pq_align;
617 
618 		if (1 << align > params->buf_size) {
619 			pr_err("%u-byte buffer too small for %d-byte alignment\n",
620 			       params->buf_size, 1 << align);
621 			break;
622 		}
623 
624 		len = dmatest_random() % params->buf_size + 1;
625 		len = (len >> align) << align;
626 		if (!len)
627 			len = 1 << align;
628 		src_off = dmatest_random() % (params->buf_size - len + 1);
629 		dst_off = dmatest_random() % (params->buf_size - len + 1);
630 
631 		src_off = (src_off >> align) << align;
632 		dst_off = (dst_off >> align) << align;
633 
634 		dmatest_init_srcs(thread->srcs, src_off, len, params->buf_size);
635 		dmatest_init_dsts(thread->dsts, dst_off, len, params->buf_size);
636 
637 		for (i = 0; i < src_cnt; i++) {
638 			u8 *buf = thread->srcs[i] + src_off;
639 
640 			dma_srcs[i] = dma_map_single(dev->dev, buf, len,
641 						     DMA_TO_DEVICE);
642 			ret = dma_mapping_error(dev->dev, dma_srcs[i]);
643 			if (ret) {
644 				unmap_src(dev->dev, dma_srcs, len, i);
645 				thread_result_add(info, result,
646 						  DMATEST_ET_MAP_SRC,
647 						  total_tests, src_off, dst_off,
648 						  len, ret);
649 				failed_tests++;
650 				continue;
651 			}
652 		}
653 		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
654 		for (i = 0; i < dst_cnt; i++) {
655 			dma_dsts[i] = dma_map_single(dev->dev, thread->dsts[i],
656 						     params->buf_size,
657 						     DMA_BIDIRECTIONAL);
658 			ret = dma_mapping_error(dev->dev, dma_dsts[i]);
659 			if (ret) {
660 				unmap_src(dev->dev, dma_srcs, len, src_cnt);
661 				unmap_dst(dev->dev, dma_dsts, params->buf_size,
662 					  i);
663 				thread_result_add(info, result,
664 						  DMATEST_ET_MAP_DST,
665 						  total_tests, src_off, dst_off,
666 						  len, ret);
667 				failed_tests++;
668 				continue;
669 			}
670 		}
671 
672 		if (thread->type == DMA_MEMCPY)
673 			tx = dev->device_prep_dma_memcpy(chan,
674 							 dma_dsts[0] + dst_off,
675 							 dma_srcs[0], len,
676 							 flags);
677 		else if (thread->type == DMA_XOR)
678 			tx = dev->device_prep_dma_xor(chan,
679 						      dma_dsts[0] + dst_off,
680 						      dma_srcs, src_cnt,
681 						      len, flags);
682 		else if (thread->type == DMA_PQ) {
683 			dma_addr_t dma_pq[dst_cnt];
684 
685 			for (i = 0; i < dst_cnt; i++)
686 				dma_pq[i] = dma_dsts[i] + dst_off;
687 			tx = dev->device_prep_dma_pq(chan, dma_pq, dma_srcs,
688 						     src_cnt, pq_coefs,
689 						     len, flags);
690 		}
691 
692 		if (!tx) {
693 			unmap_src(dev->dev, dma_srcs, len, src_cnt);
694 			unmap_dst(dev->dev, dma_dsts, params->buf_size,
695 				  dst_cnt);
696 			thread_result_add(info, result, DMATEST_ET_PREP,
697 					  total_tests, src_off, dst_off,
698 					  len, 0);
699 			msleep(100);
700 			failed_tests++;
701 			continue;
702 		}
703 
704 		done.done = false;
705 		tx->callback = dmatest_callback;
706 		tx->callback_param = &done;
707 		cookie = tx->tx_submit(tx);
708 
709 		if (dma_submit_error(cookie)) {
710 			thread_result_add(info, result, DMATEST_ET_SUBMIT,
711 					  total_tests, src_off, dst_off,
712 					  len, cookie);
713 			msleep(100);
714 			failed_tests++;
715 			continue;
716 		}
717 		dma_async_issue_pending(chan);
718 
719 		wait_event_freezable_timeout(done_wait, done.done,
720 					     msecs_to_jiffies(params->timeout));
721 
722 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
723 
724 		if (!done.done) {
725 			/*
726 			 * We're leaving the timed out dma operation with
727 			 * dangling pointer to done_wait.  To make this
728 			 * correct, we'll need to allocate wait_done for
729 			 * each test iteration and perform "who's gonna
730 			 * free it this time?" dancing.  For now, just
731 			 * leave it dangling.
732 			 */
733 			thread_result_add(info, result, DMATEST_ET_TIMEOUT,
734 					  total_tests, src_off, dst_off,
735 					  len, 0);
736 			failed_tests++;
737 			continue;
738 		} else if (status != DMA_SUCCESS) {
739 			enum dmatest_error_type type = (status == DMA_ERROR) ?
740 				DMATEST_ET_DMA_ERROR : DMATEST_ET_DMA_IN_PROGRESS;
741 			thread_result_add(info, result, type,
742 					  total_tests, src_off, dst_off,
743 					  len, status);
744 			failed_tests++;
745 			continue;
746 		}
747 
748 		/* Unmap by myself (see DMA_COMPL_SKIP_DEST_UNMAP above) */
749 		unmap_dst(dev->dev, dma_dsts, params->buf_size, dst_cnt);
750 
751 		error_count = 0;
752 
753 		pr_debug("%s: verifying source buffer...\n", thread_name);
754 		error_count += verify_result_add(info, result, total_tests,
755 				src_off, dst_off, len, thread->srcs, -1,
756 				0, PATTERN_SRC, true);
757 		error_count += verify_result_add(info, result, total_tests,
758 				src_off, dst_off, len, thread->srcs, 0,
759 				src_off, PATTERN_SRC | PATTERN_COPY, true);
760 		error_count += verify_result_add(info, result, total_tests,
761 				src_off, dst_off, len, thread->srcs, 1,
762 				src_off + len, PATTERN_SRC, true);
763 
764 		pr_debug("%s: verifying dest buffer...\n", thread_name);
765 		error_count += verify_result_add(info, result, total_tests,
766 				src_off, dst_off, len, thread->dsts, -1,
767 				0, PATTERN_DST, false);
768 		error_count += verify_result_add(info, result, total_tests,
769 				src_off, dst_off, len, thread->dsts, 0,
770 				src_off, PATTERN_SRC | PATTERN_COPY, false);
771 		error_count += verify_result_add(info, result, total_tests,
772 				src_off, dst_off, len, thread->dsts, 1,
773 				dst_off + len, PATTERN_DST, false);
774 
775 		if (error_count) {
776 			thread_result_add(info, result, DMATEST_ET_VERIFY,
777 					  total_tests, src_off, dst_off,
778 					  len, error_count);
779 			failed_tests++;
780 		} else {
781 			thread_result_add(info, result, DMATEST_ET_OK,
782 					  total_tests, src_off, dst_off,
783 					  len, 0);
784 		}
785 	}
786 
787 	ret = 0;
788 	for (i = 0; thread->dsts[i]; i++)
789 		kfree(thread->dsts[i]);
790 err_dstbuf:
791 	kfree(thread->dsts);
792 err_dsts:
793 	for (i = 0; thread->srcs[i]; i++)
794 		kfree(thread->srcs[i]);
795 err_srcbuf:
796 	kfree(thread->srcs);
797 err_srcs:
798 	kfree(pq_coefs);
799 err_thread_type:
800 	pr_notice("%s: terminating after %u tests, %u failures (status %d)\n",
801 			thread_name, total_tests, failed_tests, ret);
802 
803 	/* terminate all transfers on specified channels */
804 	if (ret)
805 		dmaengine_terminate_all(chan);
806 
807 	thread->done = true;
808 
809 	if (params->iterations > 0)
810 		while (!kthread_should_stop()) {
811 			DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wait_dmatest_exit);
812 			interruptible_sleep_on(&wait_dmatest_exit);
813 		}
814 
815 	return ret;
816 }
817 
818 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
819 {
820 	struct dmatest_thread	*thread;
821 	struct dmatest_thread	*_thread;
822 	int			ret;
823 
824 	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
825 		ret = kthread_stop(thread->task);
826 		pr_debug("dmatest: thread %s exited with status %d\n",
827 				thread->task->comm, ret);
828 		list_del(&thread->node);
829 		kfree(thread);
830 	}
831 
832 	/* terminate all transfers on specified channels */
833 	dmaengine_terminate_all(dtc->chan);
834 
835 	kfree(dtc);
836 }
837 
838 static int dmatest_add_threads(struct dmatest_info *info,
839 		struct dmatest_chan *dtc, enum dma_transaction_type type)
840 {
841 	struct dmatest_params *params = &info->params;
842 	struct dmatest_thread *thread;
843 	struct dma_chan *chan = dtc->chan;
844 	char *op;
845 	unsigned int i;
846 
847 	if (type == DMA_MEMCPY)
848 		op = "copy";
849 	else if (type == DMA_XOR)
850 		op = "xor";
851 	else if (type == DMA_PQ)
852 		op = "pq";
853 	else
854 		return -EINVAL;
855 
856 	for (i = 0; i < params->threads_per_chan; i++) {
857 		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
858 		if (!thread) {
859 			pr_warning("dmatest: No memory for %s-%s%u\n",
860 				   dma_chan_name(chan), op, i);
861 
862 			break;
863 		}
864 		thread->info = info;
865 		thread->chan = dtc->chan;
866 		thread->type = type;
867 		smp_wmb();
868 		thread->task = kthread_run(dmatest_func, thread, "%s-%s%u",
869 				dma_chan_name(chan), op, i);
870 		if (IS_ERR(thread->task)) {
871 			pr_warning("dmatest: Failed to run thread %s-%s%u\n",
872 					dma_chan_name(chan), op, i);
873 			kfree(thread);
874 			break;
875 		}
876 
877 		/* srcbuf and dstbuf are allocated by the thread itself */
878 
879 		list_add_tail(&thread->node, &dtc->threads);
880 	}
881 
882 	return i;
883 }
884 
885 static int dmatest_add_channel(struct dmatest_info *info,
886 		struct dma_chan *chan)
887 {
888 	struct dmatest_chan	*dtc;
889 	struct dma_device	*dma_dev = chan->device;
890 	unsigned int		thread_count = 0;
891 	int cnt;
892 
893 	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
894 	if (!dtc) {
895 		pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan));
896 		return -ENOMEM;
897 	}
898 
899 	dtc->chan = chan;
900 	INIT_LIST_HEAD(&dtc->threads);
901 
902 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
903 		cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
904 		thread_count += cnt > 0 ? cnt : 0;
905 	}
906 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
907 		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
908 		thread_count += cnt > 0 ? cnt : 0;
909 	}
910 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
911 		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
912 		thread_count += cnt > 0 ? cnt : 0;
913 	}
914 
915 	pr_info("dmatest: Started %u threads using %s\n",
916 		thread_count, dma_chan_name(chan));
917 
918 	list_add_tail(&dtc->node, &info->channels);
919 	info->nr_channels++;
920 
921 	return 0;
922 }
923 
924 static bool filter(struct dma_chan *chan, void *param)
925 {
926 	struct dmatest_params *params = param;
927 
928 	if (!dmatest_match_channel(params, chan) ||
929 	    !dmatest_match_device(params, chan->device))
930 		return false;
931 	else
932 		return true;
933 }
934 
935 static int __run_threaded_test(struct dmatest_info *info)
936 {
937 	dma_cap_mask_t mask;
938 	struct dma_chan *chan;
939 	struct dmatest_params *params = &info->params;
940 	int err = 0;
941 
942 	dma_cap_zero(mask);
943 	dma_cap_set(DMA_MEMCPY, mask);
944 	for (;;) {
945 		chan = dma_request_channel(mask, filter, params);
946 		if (chan) {
947 			err = dmatest_add_channel(info, chan);
948 			if (err) {
949 				dma_release_channel(chan);
950 				break; /* add_channel failed, punt */
951 			}
952 		} else
953 			break; /* no more channels available */
954 		if (params->max_channels &&
955 		    info->nr_channels >= params->max_channels)
956 			break; /* we have all we need */
957 	}
958 	return err;
959 }
960 
961 #ifndef MODULE
962 static int run_threaded_test(struct dmatest_info *info)
963 {
964 	int ret;
965 
966 	mutex_lock(&info->lock);
967 	ret = __run_threaded_test(info);
968 	mutex_unlock(&info->lock);
969 	return ret;
970 }
971 #endif
972 
973 static void __stop_threaded_test(struct dmatest_info *info)
974 {
975 	struct dmatest_chan *dtc, *_dtc;
976 	struct dma_chan *chan;
977 
978 	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
979 		list_del(&dtc->node);
980 		chan = dtc->chan;
981 		dmatest_cleanup_channel(dtc);
982 		pr_debug("dmatest: dropped channel %s\n", dma_chan_name(chan));
983 		dma_release_channel(chan);
984 	}
985 
986 	info->nr_channels = 0;
987 }
988 
989 static void stop_threaded_test(struct dmatest_info *info)
990 {
991 	mutex_lock(&info->lock);
992 	__stop_threaded_test(info);
993 	mutex_unlock(&info->lock);
994 }
995 
996 static int __restart_threaded_test(struct dmatest_info *info, bool run)
997 {
998 	struct dmatest_params *params = &info->params;
999 
1000 	/* Stop any running test first */
1001 	__stop_threaded_test(info);
1002 
1003 	if (run == false)
1004 		return 0;
1005 
1006 	/* Clear results from previous run */
1007 	result_free(info, NULL);
1008 
1009 	/* Copy test parameters */
1010 	memcpy(params, &info->dbgfs_params, sizeof(*params));
1011 
1012 	/* Run test with new parameters */
1013 	return __run_threaded_test(info);
1014 }
1015 
1016 static bool __is_threaded_test_run(struct dmatest_info *info)
1017 {
1018 	struct dmatest_chan *dtc;
1019 
1020 	list_for_each_entry(dtc, &info->channels, node) {
1021 		struct dmatest_thread *thread;
1022 
1023 		list_for_each_entry(thread, &dtc->threads, node) {
1024 			if (!thread->done)
1025 				return true;
1026 		}
1027 	}
1028 
1029 	return false;
1030 }
1031 
1032 static ssize_t dtf_write_string(void *to, size_t available, loff_t *ppos,
1033 		const void __user *from, size_t count)
1034 {
1035 	char tmp[20];
1036 	ssize_t len;
1037 
1038 	len = simple_write_to_buffer(tmp, sizeof(tmp) - 1, ppos, from, count);
1039 	if (len >= 0) {
1040 		tmp[len] = '\0';
1041 		strlcpy(to, strim(tmp), available);
1042 	}
1043 
1044 	return len;
1045 }
1046 
1047 static ssize_t dtf_read_channel(struct file *file, char __user *buf,
1048 		size_t count, loff_t *ppos)
1049 {
1050 	struct dmatest_info *info = file->private_data;
1051 	return simple_read_from_buffer(buf, count, ppos,
1052 			info->dbgfs_params.channel,
1053 			strlen(info->dbgfs_params.channel));
1054 }
1055 
1056 static ssize_t dtf_write_channel(struct file *file, const char __user *buf,
1057 		size_t size, loff_t *ppos)
1058 {
1059 	struct dmatest_info *info = file->private_data;
1060 	return dtf_write_string(info->dbgfs_params.channel,
1061 				sizeof(info->dbgfs_params.channel),
1062 				ppos, buf, size);
1063 }
1064 
1065 static const struct file_operations dtf_channel_fops = {
1066 	.read	= dtf_read_channel,
1067 	.write	= dtf_write_channel,
1068 	.open	= simple_open,
1069 	.llseek	= default_llseek,
1070 };
1071 
1072 static ssize_t dtf_read_device(struct file *file, char __user *buf,
1073 		size_t count, loff_t *ppos)
1074 {
1075 	struct dmatest_info *info = file->private_data;
1076 	return simple_read_from_buffer(buf, count, ppos,
1077 			info->dbgfs_params.device,
1078 			strlen(info->dbgfs_params.device));
1079 }
1080 
1081 static ssize_t dtf_write_device(struct file *file, const char __user *buf,
1082 		size_t size, loff_t *ppos)
1083 {
1084 	struct dmatest_info *info = file->private_data;
1085 	return dtf_write_string(info->dbgfs_params.device,
1086 				sizeof(info->dbgfs_params.device),
1087 				ppos, buf, size);
1088 }
1089 
1090 static const struct file_operations dtf_device_fops = {
1091 	.read	= dtf_read_device,
1092 	.write	= dtf_write_device,
1093 	.open	= simple_open,
1094 	.llseek	= default_llseek,
1095 };
1096 
1097 static ssize_t dtf_read_run(struct file *file, char __user *user_buf,
1098 		size_t count, loff_t *ppos)
1099 {
1100 	struct dmatest_info *info = file->private_data;
1101 	char buf[3];
1102 
1103 	mutex_lock(&info->lock);
1104 
1105 	if (__is_threaded_test_run(info)) {
1106 		buf[0] = 'Y';
1107 	} else {
1108 		__stop_threaded_test(info);
1109 		buf[0] = 'N';
1110 	}
1111 
1112 	mutex_unlock(&info->lock);
1113 	buf[1] = '\n';
1114 	buf[2] = 0x00;
1115 	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
1116 }
1117 
1118 static ssize_t dtf_write_run(struct file *file, const char __user *user_buf,
1119 		size_t count, loff_t *ppos)
1120 {
1121 	struct dmatest_info *info = file->private_data;
1122 	char buf[16];
1123 	bool bv;
1124 	int ret = 0;
1125 
1126 	if (copy_from_user(buf, user_buf, min(count, (sizeof(buf) - 1))))
1127 		return -EFAULT;
1128 
1129 	if (strtobool(buf, &bv) == 0) {
1130 		mutex_lock(&info->lock);
1131 
1132 		if (__is_threaded_test_run(info))
1133 			ret = -EBUSY;
1134 		else
1135 			ret = __restart_threaded_test(info, bv);
1136 
1137 		mutex_unlock(&info->lock);
1138 	}
1139 
1140 	return ret ? ret : count;
1141 }
1142 
1143 static const struct file_operations dtf_run_fops = {
1144 	.read	= dtf_read_run,
1145 	.write	= dtf_write_run,
1146 	.open	= simple_open,
1147 	.llseek	= default_llseek,
1148 };
1149 
1150 static int dtf_results_show(struct seq_file *sf, void *data)
1151 {
1152 	struct dmatest_info *info = sf->private;
1153 	struct dmatest_result *result;
1154 	struct dmatest_thread_result *tr;
1155 	unsigned int i;
1156 
1157 	mutex_lock(&info->results_lock);
1158 	list_for_each_entry(result, &info->results, node) {
1159 		list_for_each_entry(tr, &result->results, node) {
1160 			seq_printf(sf, "%s\n",
1161 				thread_result_get(result->name, tr));
1162 			if (tr->type == DMATEST_ET_VERIFY_BUF) {
1163 				for (i = 0; i < tr->vr->error_count; i++) {
1164 					seq_printf(sf, "\t%s\n",
1165 						verify_result_get_one(tr->vr, i));
1166 				}
1167 			}
1168 		}
1169 	}
1170 
1171 	mutex_unlock(&info->results_lock);
1172 	return 0;
1173 }
1174 
1175 static int dtf_results_open(struct inode *inode, struct file *file)
1176 {
1177 	return single_open(file, dtf_results_show, inode->i_private);
1178 }
1179 
1180 static const struct file_operations dtf_results_fops = {
1181 	.open		= dtf_results_open,
1182 	.read		= seq_read,
1183 	.llseek		= seq_lseek,
1184 	.release	= single_release,
1185 };
1186 
1187 static int dmatest_register_dbgfs(struct dmatest_info *info)
1188 {
1189 	struct dentry *d;
1190 	struct dmatest_params *params = &info->dbgfs_params;
1191 	int ret = -ENOMEM;
1192 
1193 	d = debugfs_create_dir("dmatest", NULL);
1194 	if (IS_ERR(d))
1195 		return PTR_ERR(d);
1196 	if (!d)
1197 		goto err_root;
1198 
1199 	info->root = d;
1200 
1201 	/* Copy initial values */
1202 	memcpy(params, &info->params, sizeof(*params));
1203 
1204 	/* Test parameters */
1205 
1206 	d = debugfs_create_u32("test_buf_size", S_IWUSR | S_IRUGO, info->root,
1207 			       (u32 *)&params->buf_size);
1208 	if (IS_ERR_OR_NULL(d))
1209 		goto err_node;
1210 
1211 	d = debugfs_create_file("channel", S_IRUGO | S_IWUSR, info->root,
1212 				info, &dtf_channel_fops);
1213 	if (IS_ERR_OR_NULL(d))
1214 		goto err_node;
1215 
1216 	d = debugfs_create_file("device", S_IRUGO | S_IWUSR, info->root,
1217 				info, &dtf_device_fops);
1218 	if (IS_ERR_OR_NULL(d))
1219 		goto err_node;
1220 
1221 	d = debugfs_create_u32("threads_per_chan", S_IWUSR | S_IRUGO, info->root,
1222 			       (u32 *)&params->threads_per_chan);
1223 	if (IS_ERR_OR_NULL(d))
1224 		goto err_node;
1225 
1226 	d = debugfs_create_u32("max_channels", S_IWUSR | S_IRUGO, info->root,
1227 			       (u32 *)&params->max_channels);
1228 	if (IS_ERR_OR_NULL(d))
1229 		goto err_node;
1230 
1231 	d = debugfs_create_u32("iterations", S_IWUSR | S_IRUGO, info->root,
1232 			       (u32 *)&params->iterations);
1233 	if (IS_ERR_OR_NULL(d))
1234 		goto err_node;
1235 
1236 	d = debugfs_create_u32("xor_sources", S_IWUSR | S_IRUGO, info->root,
1237 			       (u32 *)&params->xor_sources);
1238 	if (IS_ERR_OR_NULL(d))
1239 		goto err_node;
1240 
1241 	d = debugfs_create_u32("pq_sources", S_IWUSR | S_IRUGO, info->root,
1242 			       (u32 *)&params->pq_sources);
1243 	if (IS_ERR_OR_NULL(d))
1244 		goto err_node;
1245 
1246 	d = debugfs_create_u32("timeout", S_IWUSR | S_IRUGO, info->root,
1247 			       (u32 *)&params->timeout);
1248 	if (IS_ERR_OR_NULL(d))
1249 		goto err_node;
1250 
1251 	/* Run or stop threaded test */
1252 	d = debugfs_create_file("run", S_IWUSR | S_IRUGO, info->root,
1253 				info, &dtf_run_fops);
1254 	if (IS_ERR_OR_NULL(d))
1255 		goto err_node;
1256 
1257 	/* Results of test in progress */
1258 	d = debugfs_create_file("results", S_IRUGO, info->root, info,
1259 				&dtf_results_fops);
1260 	if (IS_ERR_OR_NULL(d))
1261 		goto err_node;
1262 
1263 	return 0;
1264 
1265 err_node:
1266 	debugfs_remove_recursive(info->root);
1267 err_root:
1268 	pr_err("dmatest: Failed to initialize debugfs\n");
1269 	return ret;
1270 }
1271 
1272 static int __init dmatest_init(void)
1273 {
1274 	struct dmatest_info *info = &test_info;
1275 	struct dmatest_params *params = &info->params;
1276 	int ret;
1277 
1278 	memset(info, 0, sizeof(*info));
1279 
1280 	mutex_init(&info->lock);
1281 	INIT_LIST_HEAD(&info->channels);
1282 
1283 	mutex_init(&info->results_lock);
1284 	INIT_LIST_HEAD(&info->results);
1285 
1286 	/* Set default parameters */
1287 	params->buf_size = test_buf_size;
1288 	strlcpy(params->channel, test_channel, sizeof(params->channel));
1289 	strlcpy(params->device, test_device, sizeof(params->device));
1290 	params->threads_per_chan = threads_per_chan;
1291 	params->max_channels = max_channels;
1292 	params->iterations = iterations;
1293 	params->xor_sources = xor_sources;
1294 	params->pq_sources = pq_sources;
1295 	params->timeout = timeout;
1296 
1297 	ret = dmatest_register_dbgfs(info);
1298 	if (ret)
1299 		return ret;
1300 
1301 #ifdef MODULE
1302 	return 0;
1303 #else
1304 	return run_threaded_test(info);
1305 #endif
1306 }
1307 /* when compiled-in wait for drivers to load first */
1308 late_initcall(dmatest_init);
1309 
1310 static void __exit dmatest_exit(void)
1311 {
1312 	struct dmatest_info *info = &test_info;
1313 
1314 	debugfs_remove_recursive(info->root);
1315 	stop_threaded_test(info);
1316 	result_free(info, NULL);
1317 }
1318 module_exit(dmatest_exit);
1319 
1320 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1321 MODULE_LICENSE("GPL v2");
1322