xref: /openbmc/linux/drivers/dma/dmatest.c (revision e23feb16)
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 | S_IWUSR);
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),
33 		S_IRUGO | S_IWUSR);
34 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
35 
36 static char test_device[20];
37 module_param_string(device, test_device, sizeof(test_device),
38 		S_IRUGO | S_IWUSR);
39 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
40 
41 static unsigned int threads_per_chan = 1;
42 module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
43 MODULE_PARM_DESC(threads_per_chan,
44 		"Number of threads to start per channel (default: 1)");
45 
46 static unsigned int max_channels;
47 module_param(max_channels, uint, S_IRUGO | S_IWUSR);
48 MODULE_PARM_DESC(max_channels,
49 		"Maximum number of channels to use (default: all)");
50 
51 static unsigned int iterations;
52 module_param(iterations, uint, S_IRUGO | S_IWUSR);
53 MODULE_PARM_DESC(iterations,
54 		"Iterations before stopping test (default: infinite)");
55 
56 static unsigned int xor_sources = 3;
57 module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
58 MODULE_PARM_DESC(xor_sources,
59 		"Number of xor source buffers (default: 3)");
60 
61 static unsigned int pq_sources = 3;
62 module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
63 MODULE_PARM_DESC(pq_sources,
64 		"Number of p+q source buffers (default: 3)");
65 
66 static int timeout = 3000;
67 module_param(timeout, uint, S_IRUGO | S_IWUSR);
68 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
69 		 "Pass -1 for infinite timeout");
70 
71 /* Maximum amount of mismatched bytes in buffer to print */
72 #define MAX_ERROR_COUNT		32
73 
74 /*
75  * Initialization patterns. All bytes in the source buffer has bit 7
76  * set, all bytes in the destination buffer has bit 7 cleared.
77  *
78  * Bit 6 is set for all bytes which are to be copied by the DMA
79  * engine. Bit 5 is set for all bytes which are to be overwritten by
80  * the DMA engine.
81  *
82  * The remaining bits are the inverse of a counter which increments by
83  * one for each byte address.
84  */
85 #define PATTERN_SRC		0x80
86 #define PATTERN_DST		0x00
87 #define PATTERN_COPY		0x40
88 #define PATTERN_OVERWRITE	0x20
89 #define PATTERN_COUNT_MASK	0x1f
90 
91 enum dmatest_error_type {
92 	DMATEST_ET_OK,
93 	DMATEST_ET_MAP_SRC,
94 	DMATEST_ET_MAP_DST,
95 	DMATEST_ET_PREP,
96 	DMATEST_ET_SUBMIT,
97 	DMATEST_ET_TIMEOUT,
98 	DMATEST_ET_DMA_ERROR,
99 	DMATEST_ET_DMA_IN_PROGRESS,
100 	DMATEST_ET_VERIFY,
101 	DMATEST_ET_VERIFY_BUF,
102 };
103 
104 struct dmatest_verify_buffer {
105 	unsigned int	index;
106 	u8		expected;
107 	u8		actual;
108 };
109 
110 struct dmatest_verify_result {
111 	unsigned int			error_count;
112 	struct dmatest_verify_buffer	data[MAX_ERROR_COUNT];
113 	u8				pattern;
114 	bool				is_srcbuf;
115 };
116 
117 struct dmatest_thread_result {
118 	struct list_head	node;
119 	unsigned int		n;
120 	unsigned int		src_off;
121 	unsigned int		dst_off;
122 	unsigned int		len;
123 	enum dmatest_error_type	type;
124 	union {
125 		unsigned long			data;
126 		dma_cookie_t			cookie;
127 		enum dma_status			status;
128 		int				error;
129 		struct dmatest_verify_result	*vr;
130 	};
131 };
132 
133 struct dmatest_result {
134 	struct list_head	node;
135 	char			*name;
136 	struct list_head	results;
137 };
138 
139 struct dmatest_info;
140 
141 struct dmatest_thread {
142 	struct list_head	node;
143 	struct dmatest_info	*info;
144 	struct task_struct	*task;
145 	struct dma_chan		*chan;
146 	u8			**srcs;
147 	u8			**dsts;
148 	enum dma_transaction_type type;
149 	bool			done;
150 };
151 
152 struct dmatest_chan {
153 	struct list_head	node;
154 	struct dma_chan		*chan;
155 	struct list_head	threads;
156 };
157 
158 /**
159  * struct dmatest_params - test parameters.
160  * @buf_size:		size of the memcpy test buffer
161  * @channel:		bus ID of the channel to test
162  * @device:		bus ID of the DMA Engine to test
163  * @threads_per_chan:	number of threads to start per channel
164  * @max_channels:	maximum number of channels to use
165  * @iterations:		iterations before stopping test
166  * @xor_sources:	number of xor source buffers
167  * @pq_sources:		number of p+q source buffers
168  * @timeout:		transfer timeout in msec, -1 for infinite timeout
169  */
170 struct dmatest_params {
171 	unsigned int	buf_size;
172 	char		channel[20];
173 	char		device[20];
174 	unsigned int	threads_per_chan;
175 	unsigned int	max_channels;
176 	unsigned int	iterations;
177 	unsigned int	xor_sources;
178 	unsigned int	pq_sources;
179 	int		timeout;
180 };
181 
182 /**
183  * struct dmatest_info - test information.
184  * @params:		test parameters
185  * @lock:		access protection to the fields of this structure
186  */
187 struct dmatest_info {
188 	/* Test parameters */
189 	struct dmatest_params	params;
190 
191 	/* Internal state */
192 	struct list_head	channels;
193 	unsigned int		nr_channels;
194 	struct mutex		lock;
195 
196 	/* debugfs related stuff */
197 	struct dentry		*root;
198 
199 	/* Test results */
200 	struct list_head	results;
201 	struct mutex		results_lock;
202 };
203 
204 static struct dmatest_info test_info;
205 
206 static bool dmatest_match_channel(struct dmatest_params *params,
207 		struct dma_chan *chan)
208 {
209 	if (params->channel[0] == '\0')
210 		return true;
211 	return strcmp(dma_chan_name(chan), params->channel) == 0;
212 }
213 
214 static bool dmatest_match_device(struct dmatest_params *params,
215 		struct dma_device *device)
216 {
217 	if (params->device[0] == '\0')
218 		return true;
219 	return strcmp(dev_name(device->dev), params->device) == 0;
220 }
221 
222 static unsigned long dmatest_random(void)
223 {
224 	unsigned long buf;
225 
226 	get_random_bytes(&buf, sizeof(buf));
227 	return buf;
228 }
229 
230 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
231 		unsigned int buf_size)
232 {
233 	unsigned int i;
234 	u8 *buf;
235 
236 	for (; (buf = *bufs); bufs++) {
237 		for (i = 0; i < start; i++)
238 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
239 		for ( ; i < start + len; i++)
240 			buf[i] = PATTERN_SRC | PATTERN_COPY
241 				| (~i & PATTERN_COUNT_MASK);
242 		for ( ; i < buf_size; i++)
243 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
244 		buf++;
245 	}
246 }
247 
248 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
249 		unsigned int buf_size)
250 {
251 	unsigned int i;
252 	u8 *buf;
253 
254 	for (; (buf = *bufs); bufs++) {
255 		for (i = 0; i < start; i++)
256 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
257 		for ( ; i < start + len; i++)
258 			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
259 				| (~i & PATTERN_COUNT_MASK);
260 		for ( ; i < buf_size; i++)
261 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
262 	}
263 }
264 
265 static unsigned int dmatest_verify(struct dmatest_verify_result *vr, u8 **bufs,
266 		unsigned int start, unsigned int end, unsigned int counter,
267 		u8 pattern, bool is_srcbuf)
268 {
269 	unsigned int i;
270 	unsigned int error_count = 0;
271 	u8 actual;
272 	u8 expected;
273 	u8 *buf;
274 	unsigned int counter_orig = counter;
275 	struct dmatest_verify_buffer *vb;
276 
277 	for (; (buf = *bufs); bufs++) {
278 		counter = counter_orig;
279 		for (i = start; i < end; i++) {
280 			actual = buf[i];
281 			expected = pattern | (~counter & PATTERN_COUNT_MASK);
282 			if (actual != expected) {
283 				if (error_count < MAX_ERROR_COUNT && vr) {
284 					vb = &vr->data[error_count];
285 					vb->index = i;
286 					vb->expected = expected;
287 					vb->actual = actual;
288 				}
289 				error_count++;
290 			}
291 			counter++;
292 		}
293 	}
294 
295 	if (error_count > MAX_ERROR_COUNT)
296 		pr_warning("%s: %u errors suppressed\n",
297 			current->comm, error_count - MAX_ERROR_COUNT);
298 
299 	return error_count;
300 }
301 
302 /* poor man's completion - we want to use wait_event_freezable() on it */
303 struct dmatest_done {
304 	bool			done;
305 	wait_queue_head_t	*wait;
306 };
307 
308 static void dmatest_callback(void *arg)
309 {
310 	struct dmatest_done *done = arg;
311 
312 	done->done = true;
313 	wake_up_all(done->wait);
314 }
315 
316 static inline void unmap_src(struct device *dev, dma_addr_t *addr, size_t len,
317 			     unsigned int count)
318 {
319 	while (count--)
320 		dma_unmap_single(dev, addr[count], len, DMA_TO_DEVICE);
321 }
322 
323 static inline void unmap_dst(struct device *dev, dma_addr_t *addr, size_t len,
324 			     unsigned int count)
325 {
326 	while (count--)
327 		dma_unmap_single(dev, addr[count], len, DMA_BIDIRECTIONAL);
328 }
329 
330 static unsigned int min_odd(unsigned int x, unsigned int y)
331 {
332 	unsigned int val = min(x, y);
333 
334 	return val % 2 ? val : val - 1;
335 }
336 
337 static char *verify_result_get_one(struct dmatest_verify_result *vr,
338 		unsigned int i)
339 {
340 	struct dmatest_verify_buffer *vb = &vr->data[i];
341 	u8 diff = vb->actual ^ vr->pattern;
342 	static char buf[512];
343 	char *msg;
344 
345 	if (vr->is_srcbuf)
346 		msg = "srcbuf overwritten!";
347 	else if ((vr->pattern & PATTERN_COPY)
348 			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
349 		msg = "dstbuf not copied!";
350 	else if (diff & PATTERN_SRC)
351 		msg = "dstbuf was copied!";
352 	else
353 		msg = "dstbuf mismatch!";
354 
355 	snprintf(buf, sizeof(buf) - 1, "%s [0x%x] Expected %02x, got %02x", msg,
356 		 vb->index, vb->expected, vb->actual);
357 
358 	return buf;
359 }
360 
361 static char *thread_result_get(const char *name,
362 		struct dmatest_thread_result *tr)
363 {
364 	static const char * const messages[] = {
365 		[DMATEST_ET_OK]			= "No errors",
366 		[DMATEST_ET_MAP_SRC]		= "src mapping error",
367 		[DMATEST_ET_MAP_DST]		= "dst mapping error",
368 		[DMATEST_ET_PREP]		= "prep error",
369 		[DMATEST_ET_SUBMIT]		= "submit error",
370 		[DMATEST_ET_TIMEOUT]		= "test timed out",
371 		[DMATEST_ET_DMA_ERROR]		=
372 			"got completion callback (DMA_ERROR)",
373 		[DMATEST_ET_DMA_IN_PROGRESS]	=
374 			"got completion callback (DMA_IN_PROGRESS)",
375 		[DMATEST_ET_VERIFY]		= "errors",
376 		[DMATEST_ET_VERIFY_BUF]		= "verify errors",
377 	};
378 	static char buf[512];
379 
380 	snprintf(buf, sizeof(buf) - 1,
381 		 "%s: #%u: %s with src_off=0x%x ""dst_off=0x%x len=0x%x (%lu)",
382 		 name, tr->n, messages[tr->type], tr->src_off, tr->dst_off,
383 		 tr->len, tr->data);
384 
385 	return buf;
386 }
387 
388 static int thread_result_add(struct dmatest_info *info,
389 		struct dmatest_result *r, enum dmatest_error_type type,
390 		unsigned int n, unsigned int src_off, unsigned int dst_off,
391 		unsigned int len, unsigned long data)
392 {
393 	struct dmatest_thread_result *tr;
394 
395 	tr = kzalloc(sizeof(*tr), GFP_KERNEL);
396 	if (!tr)
397 		return -ENOMEM;
398 
399 	tr->type = type;
400 	tr->n = n;
401 	tr->src_off = src_off;
402 	tr->dst_off = dst_off;
403 	tr->len = len;
404 	tr->data = data;
405 
406 	mutex_lock(&info->results_lock);
407 	list_add_tail(&tr->node, &r->results);
408 	mutex_unlock(&info->results_lock);
409 
410 	if (tr->type == DMATEST_ET_OK)
411 		pr_debug("%s\n", thread_result_get(r->name, tr));
412 	else
413 		pr_warn("%s\n", thread_result_get(r->name, tr));
414 
415 	return 0;
416 }
417 
418 static unsigned int verify_result_add(struct dmatest_info *info,
419 		struct dmatest_result *r, unsigned int n,
420 		unsigned int src_off, unsigned int dst_off, unsigned int len,
421 		u8 **bufs, int whence, unsigned int counter, u8 pattern,
422 		bool is_srcbuf)
423 {
424 	struct dmatest_verify_result *vr;
425 	unsigned int error_count;
426 	unsigned int buf_off = is_srcbuf ? src_off : dst_off;
427 	unsigned int start, end;
428 
429 	if (whence < 0) {
430 		start = 0;
431 		end = buf_off;
432 	} else if (whence > 0) {
433 		start = buf_off + len;
434 		end = info->params.buf_size;
435 	} else {
436 		start = buf_off;
437 		end = buf_off + len;
438 	}
439 
440 	vr = kmalloc(sizeof(*vr), GFP_KERNEL);
441 	if (!vr) {
442 		pr_warn("dmatest: No memory to store verify result\n");
443 		return dmatest_verify(NULL, bufs, start, end, counter, pattern,
444 				      is_srcbuf);
445 	}
446 
447 	vr->pattern = pattern;
448 	vr->is_srcbuf = is_srcbuf;
449 
450 	error_count = dmatest_verify(vr, bufs, start, end, counter, pattern,
451 				     is_srcbuf);
452 	if (error_count) {
453 		vr->error_count = error_count;
454 		thread_result_add(info, r, DMATEST_ET_VERIFY_BUF, n, src_off,
455 				  dst_off, len, (unsigned long)vr);
456 		return error_count;
457 	}
458 
459 	kfree(vr);
460 	return 0;
461 }
462 
463 static void result_free(struct dmatest_info *info, const char *name)
464 {
465 	struct dmatest_result *r, *_r;
466 
467 	mutex_lock(&info->results_lock);
468 	list_for_each_entry_safe(r, _r, &info->results, node) {
469 		struct dmatest_thread_result *tr, *_tr;
470 
471 		if (name && strcmp(r->name, name))
472 			continue;
473 
474 		list_for_each_entry_safe(tr, _tr, &r->results, node) {
475 			if (tr->type == DMATEST_ET_VERIFY_BUF)
476 				kfree(tr->vr);
477 			list_del(&tr->node);
478 			kfree(tr);
479 		}
480 
481 		kfree(r->name);
482 		list_del(&r->node);
483 		kfree(r);
484 	}
485 
486 	mutex_unlock(&info->results_lock);
487 }
488 
489 static struct dmatest_result *result_init(struct dmatest_info *info,
490 		const char *name)
491 {
492 	struct dmatest_result *r;
493 
494 	r = kzalloc(sizeof(*r), GFP_KERNEL);
495 	if (r) {
496 		r->name = kstrdup(name, GFP_KERNEL);
497 		INIT_LIST_HEAD(&r->results);
498 		mutex_lock(&info->results_lock);
499 		list_add_tail(&r->node, &info->results);
500 		mutex_unlock(&info->results_lock);
501 	}
502 	return r;
503 }
504 
505 /*
506  * This function repeatedly tests DMA transfers of various lengths and
507  * offsets for a given operation type until it is told to exit by
508  * kthread_stop(). There may be multiple threads running this function
509  * in parallel for a single channel, and there may be multiple channels
510  * being tested in parallel.
511  *
512  * Before each test, the source and destination buffer is initialized
513  * with a known pattern. This pattern is different depending on
514  * whether it's in an area which is supposed to be copied or
515  * overwritten, and different in the source and destination buffers.
516  * So if the DMA engine doesn't copy exactly what we tell it to copy,
517  * we'll notice.
518  */
519 static int dmatest_func(void *data)
520 {
521 	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
522 	struct dmatest_thread	*thread = data;
523 	struct dmatest_done	done = { .wait = &done_wait };
524 	struct dmatest_info	*info;
525 	struct dmatest_params	*params;
526 	struct dma_chan		*chan;
527 	struct dma_device	*dev;
528 	const char		*thread_name;
529 	unsigned int		src_off, dst_off, len;
530 	unsigned int		error_count;
531 	unsigned int		failed_tests = 0;
532 	unsigned int		total_tests = 0;
533 	dma_cookie_t		cookie;
534 	enum dma_status		status;
535 	enum dma_ctrl_flags 	flags;
536 	u8			*pq_coefs = NULL;
537 	int			ret;
538 	int			src_cnt;
539 	int			dst_cnt;
540 	int			i;
541 	struct dmatest_result	*result;
542 
543 	thread_name = current->comm;
544 	set_freezable();
545 
546 	ret = -ENOMEM;
547 
548 	smp_rmb();
549 	info = thread->info;
550 	params = &info->params;
551 	chan = thread->chan;
552 	dev = chan->device;
553 	if (thread->type == DMA_MEMCPY)
554 		src_cnt = dst_cnt = 1;
555 	else if (thread->type == DMA_XOR) {
556 		/* force odd to ensure dst = src */
557 		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
558 		dst_cnt = 1;
559 	} else if (thread->type == DMA_PQ) {
560 		/* force odd to ensure dst = src */
561 		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
562 		dst_cnt = 2;
563 
564 		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
565 		if (!pq_coefs)
566 			goto err_thread_type;
567 
568 		for (i = 0; i < src_cnt; i++)
569 			pq_coefs[i] = 1;
570 	} else
571 		goto err_thread_type;
572 
573 	result = result_init(info, thread_name);
574 	if (!result)
575 		goto err_srcs;
576 
577 	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
578 	if (!thread->srcs)
579 		goto err_srcs;
580 	for (i = 0; i < src_cnt; i++) {
581 		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
582 		if (!thread->srcs[i])
583 			goto err_srcbuf;
584 	}
585 	thread->srcs[i] = NULL;
586 
587 	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
588 	if (!thread->dsts)
589 		goto err_dsts;
590 	for (i = 0; i < dst_cnt; i++) {
591 		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
592 		if (!thread->dsts[i])
593 			goto err_dstbuf;
594 	}
595 	thread->dsts[i] = NULL;
596 
597 	set_user_nice(current, 10);
598 
599 	/*
600 	 * src buffers are freed by the DMAEngine code with dma_unmap_single()
601 	 * dst buffers are freed by ourselves below
602 	 */
603 	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT
604 	      | DMA_COMPL_SKIP_DEST_UNMAP | DMA_COMPL_SRC_UNMAP_SINGLE;
605 
606 	while (!kthread_should_stop()
607 	       && !(params->iterations && total_tests >= params->iterations)) {
608 		struct dma_async_tx_descriptor *tx = NULL;
609 		dma_addr_t dma_srcs[src_cnt];
610 		dma_addr_t dma_dsts[dst_cnt];
611 		u8 align = 0;
612 
613 		total_tests++;
614 
615 		/* honor alignment restrictions */
616 		if (thread->type == DMA_MEMCPY)
617 			align = dev->copy_align;
618 		else if (thread->type == DMA_XOR)
619 			align = dev->xor_align;
620 		else if (thread->type == DMA_PQ)
621 			align = dev->pq_align;
622 
623 		if (1 << align > params->buf_size) {
624 			pr_err("%u-byte buffer too small for %d-byte alignment\n",
625 			       params->buf_size, 1 << align);
626 			break;
627 		}
628 
629 		len = dmatest_random() % params->buf_size + 1;
630 		len = (len >> align) << align;
631 		if (!len)
632 			len = 1 << align;
633 		src_off = dmatest_random() % (params->buf_size - len + 1);
634 		dst_off = dmatest_random() % (params->buf_size - len + 1);
635 
636 		src_off = (src_off >> align) << align;
637 		dst_off = (dst_off >> align) << align;
638 
639 		dmatest_init_srcs(thread->srcs, src_off, len, params->buf_size);
640 		dmatest_init_dsts(thread->dsts, dst_off, len, params->buf_size);
641 
642 		for (i = 0; i < src_cnt; i++) {
643 			u8 *buf = thread->srcs[i] + src_off;
644 
645 			dma_srcs[i] = dma_map_single(dev->dev, buf, len,
646 						     DMA_TO_DEVICE);
647 			ret = dma_mapping_error(dev->dev, dma_srcs[i]);
648 			if (ret) {
649 				unmap_src(dev->dev, dma_srcs, len, i);
650 				thread_result_add(info, result,
651 						  DMATEST_ET_MAP_SRC,
652 						  total_tests, src_off, dst_off,
653 						  len, ret);
654 				failed_tests++;
655 				continue;
656 			}
657 		}
658 		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
659 		for (i = 0; i < dst_cnt; i++) {
660 			dma_dsts[i] = dma_map_single(dev->dev, thread->dsts[i],
661 						     params->buf_size,
662 						     DMA_BIDIRECTIONAL);
663 			ret = dma_mapping_error(dev->dev, dma_dsts[i]);
664 			if (ret) {
665 				unmap_src(dev->dev, dma_srcs, len, src_cnt);
666 				unmap_dst(dev->dev, dma_dsts, params->buf_size,
667 					  i);
668 				thread_result_add(info, result,
669 						  DMATEST_ET_MAP_DST,
670 						  total_tests, src_off, dst_off,
671 						  len, ret);
672 				failed_tests++;
673 				continue;
674 			}
675 		}
676 
677 		if (thread->type == DMA_MEMCPY)
678 			tx = dev->device_prep_dma_memcpy(chan,
679 							 dma_dsts[0] + dst_off,
680 							 dma_srcs[0], len,
681 							 flags);
682 		else if (thread->type == DMA_XOR)
683 			tx = dev->device_prep_dma_xor(chan,
684 						      dma_dsts[0] + dst_off,
685 						      dma_srcs, src_cnt,
686 						      len, flags);
687 		else if (thread->type == DMA_PQ) {
688 			dma_addr_t dma_pq[dst_cnt];
689 
690 			for (i = 0; i < dst_cnt; i++)
691 				dma_pq[i] = dma_dsts[i] + dst_off;
692 			tx = dev->device_prep_dma_pq(chan, dma_pq, dma_srcs,
693 						     src_cnt, pq_coefs,
694 						     len, flags);
695 		}
696 
697 		if (!tx) {
698 			unmap_src(dev->dev, dma_srcs, len, src_cnt);
699 			unmap_dst(dev->dev, dma_dsts, params->buf_size,
700 				  dst_cnt);
701 			thread_result_add(info, result, DMATEST_ET_PREP,
702 					  total_tests, src_off, dst_off,
703 					  len, 0);
704 			msleep(100);
705 			failed_tests++;
706 			continue;
707 		}
708 
709 		done.done = false;
710 		tx->callback = dmatest_callback;
711 		tx->callback_param = &done;
712 		cookie = tx->tx_submit(tx);
713 
714 		if (dma_submit_error(cookie)) {
715 			thread_result_add(info, result, DMATEST_ET_SUBMIT,
716 					  total_tests, src_off, dst_off,
717 					  len, cookie);
718 			msleep(100);
719 			failed_tests++;
720 			continue;
721 		}
722 		dma_async_issue_pending(chan);
723 
724 		wait_event_freezable_timeout(done_wait, done.done,
725 					     msecs_to_jiffies(params->timeout));
726 
727 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
728 
729 		if (!done.done) {
730 			/*
731 			 * We're leaving the timed out dma operation with
732 			 * dangling pointer to done_wait.  To make this
733 			 * correct, we'll need to allocate wait_done for
734 			 * each test iteration and perform "who's gonna
735 			 * free it this time?" dancing.  For now, just
736 			 * leave it dangling.
737 			 */
738 			thread_result_add(info, result, DMATEST_ET_TIMEOUT,
739 					  total_tests, src_off, dst_off,
740 					  len, 0);
741 			failed_tests++;
742 			continue;
743 		} else if (status != DMA_SUCCESS) {
744 			enum dmatest_error_type type = (status == DMA_ERROR) ?
745 				DMATEST_ET_DMA_ERROR : DMATEST_ET_DMA_IN_PROGRESS;
746 			thread_result_add(info, result, type,
747 					  total_tests, src_off, dst_off,
748 					  len, status);
749 			failed_tests++;
750 			continue;
751 		}
752 
753 		/* Unmap by myself (see DMA_COMPL_SKIP_DEST_UNMAP above) */
754 		unmap_dst(dev->dev, dma_dsts, params->buf_size, dst_cnt);
755 
756 		error_count = 0;
757 
758 		pr_debug("%s: verifying source buffer...\n", thread_name);
759 		error_count += verify_result_add(info, result, total_tests,
760 				src_off, dst_off, len, thread->srcs, -1,
761 				0, PATTERN_SRC, true);
762 		error_count += verify_result_add(info, result, total_tests,
763 				src_off, dst_off, len, thread->srcs, 0,
764 				src_off, PATTERN_SRC | PATTERN_COPY, true);
765 		error_count += verify_result_add(info, result, total_tests,
766 				src_off, dst_off, len, thread->srcs, 1,
767 				src_off + len, PATTERN_SRC, true);
768 
769 		pr_debug("%s: verifying dest buffer...\n", thread_name);
770 		error_count += verify_result_add(info, result, total_tests,
771 				src_off, dst_off, len, thread->dsts, -1,
772 				0, PATTERN_DST, false);
773 		error_count += verify_result_add(info, result, total_tests,
774 				src_off, dst_off, len, thread->dsts, 0,
775 				src_off, PATTERN_SRC | PATTERN_COPY, false);
776 		error_count += verify_result_add(info, result, total_tests,
777 				src_off, dst_off, len, thread->dsts, 1,
778 				dst_off + len, PATTERN_DST, false);
779 
780 		if (error_count) {
781 			thread_result_add(info, result, DMATEST_ET_VERIFY,
782 					  total_tests, src_off, dst_off,
783 					  len, error_count);
784 			failed_tests++;
785 		} else {
786 			thread_result_add(info, result, DMATEST_ET_OK,
787 					  total_tests, src_off, dst_off,
788 					  len, 0);
789 		}
790 	}
791 
792 	ret = 0;
793 	for (i = 0; thread->dsts[i]; i++)
794 		kfree(thread->dsts[i]);
795 err_dstbuf:
796 	kfree(thread->dsts);
797 err_dsts:
798 	for (i = 0; thread->srcs[i]; i++)
799 		kfree(thread->srcs[i]);
800 err_srcbuf:
801 	kfree(thread->srcs);
802 err_srcs:
803 	kfree(pq_coefs);
804 err_thread_type:
805 	pr_notice("%s: terminating after %u tests, %u failures (status %d)\n",
806 			thread_name, total_tests, failed_tests, ret);
807 
808 	/* terminate all transfers on specified channels */
809 	if (ret)
810 		dmaengine_terminate_all(chan);
811 
812 	thread->done = true;
813 
814 	if (params->iterations > 0)
815 		while (!kthread_should_stop()) {
816 			DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wait_dmatest_exit);
817 			interruptible_sleep_on(&wait_dmatest_exit);
818 		}
819 
820 	return ret;
821 }
822 
823 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
824 {
825 	struct dmatest_thread	*thread;
826 	struct dmatest_thread	*_thread;
827 	int			ret;
828 
829 	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
830 		ret = kthread_stop(thread->task);
831 		pr_debug("dmatest: thread %s exited with status %d\n",
832 				thread->task->comm, ret);
833 		list_del(&thread->node);
834 		kfree(thread);
835 	}
836 
837 	/* terminate all transfers on specified channels */
838 	dmaengine_terminate_all(dtc->chan);
839 
840 	kfree(dtc);
841 }
842 
843 static int dmatest_add_threads(struct dmatest_info *info,
844 		struct dmatest_chan *dtc, enum dma_transaction_type type)
845 {
846 	struct dmatest_params *params = &info->params;
847 	struct dmatest_thread *thread;
848 	struct dma_chan *chan = dtc->chan;
849 	char *op;
850 	unsigned int i;
851 
852 	if (type == DMA_MEMCPY)
853 		op = "copy";
854 	else if (type == DMA_XOR)
855 		op = "xor";
856 	else if (type == DMA_PQ)
857 		op = "pq";
858 	else
859 		return -EINVAL;
860 
861 	for (i = 0; i < params->threads_per_chan; i++) {
862 		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
863 		if (!thread) {
864 			pr_warning("dmatest: No memory for %s-%s%u\n",
865 				   dma_chan_name(chan), op, i);
866 
867 			break;
868 		}
869 		thread->info = info;
870 		thread->chan = dtc->chan;
871 		thread->type = type;
872 		smp_wmb();
873 		thread->task = kthread_run(dmatest_func, thread, "%s-%s%u",
874 				dma_chan_name(chan), op, i);
875 		if (IS_ERR(thread->task)) {
876 			pr_warning("dmatest: Failed to run thread %s-%s%u\n",
877 					dma_chan_name(chan), op, i);
878 			kfree(thread);
879 			break;
880 		}
881 
882 		/* srcbuf and dstbuf are allocated by the thread itself */
883 
884 		list_add_tail(&thread->node, &dtc->threads);
885 	}
886 
887 	return i;
888 }
889 
890 static int dmatest_add_channel(struct dmatest_info *info,
891 		struct dma_chan *chan)
892 {
893 	struct dmatest_chan	*dtc;
894 	struct dma_device	*dma_dev = chan->device;
895 	unsigned int		thread_count = 0;
896 	int cnt;
897 
898 	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
899 	if (!dtc) {
900 		pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan));
901 		return -ENOMEM;
902 	}
903 
904 	dtc->chan = chan;
905 	INIT_LIST_HEAD(&dtc->threads);
906 
907 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
908 		cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
909 		thread_count += cnt > 0 ? cnt : 0;
910 	}
911 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
912 		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
913 		thread_count += cnt > 0 ? cnt : 0;
914 	}
915 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
916 		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
917 		thread_count += cnt > 0 ? cnt : 0;
918 	}
919 
920 	pr_info("dmatest: Started %u threads using %s\n",
921 		thread_count, dma_chan_name(chan));
922 
923 	list_add_tail(&dtc->node, &info->channels);
924 	info->nr_channels++;
925 
926 	return 0;
927 }
928 
929 static bool filter(struct dma_chan *chan, void *param)
930 {
931 	struct dmatest_params *params = param;
932 
933 	if (!dmatest_match_channel(params, chan) ||
934 	    !dmatest_match_device(params, chan->device))
935 		return false;
936 	else
937 		return true;
938 }
939 
940 static int __run_threaded_test(struct dmatest_info *info)
941 {
942 	dma_cap_mask_t mask;
943 	struct dma_chan *chan;
944 	struct dmatest_params *params = &info->params;
945 	int err = 0;
946 
947 	dma_cap_zero(mask);
948 	dma_cap_set(DMA_MEMCPY, mask);
949 	for (;;) {
950 		chan = dma_request_channel(mask, filter, params);
951 		if (chan) {
952 			err = dmatest_add_channel(info, chan);
953 			if (err) {
954 				dma_release_channel(chan);
955 				break; /* add_channel failed, punt */
956 			}
957 		} else
958 			break; /* no more channels available */
959 		if (params->max_channels &&
960 		    info->nr_channels >= params->max_channels)
961 			break; /* we have all we need */
962 	}
963 	return err;
964 }
965 
966 #ifndef MODULE
967 static int run_threaded_test(struct dmatest_info *info)
968 {
969 	int ret;
970 
971 	mutex_lock(&info->lock);
972 	ret = __run_threaded_test(info);
973 	mutex_unlock(&info->lock);
974 	return ret;
975 }
976 #endif
977 
978 static void __stop_threaded_test(struct dmatest_info *info)
979 {
980 	struct dmatest_chan *dtc, *_dtc;
981 	struct dma_chan *chan;
982 
983 	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
984 		list_del(&dtc->node);
985 		chan = dtc->chan;
986 		dmatest_cleanup_channel(dtc);
987 		pr_debug("dmatest: dropped channel %s\n", dma_chan_name(chan));
988 		dma_release_channel(chan);
989 	}
990 
991 	info->nr_channels = 0;
992 }
993 
994 static void stop_threaded_test(struct dmatest_info *info)
995 {
996 	mutex_lock(&info->lock);
997 	__stop_threaded_test(info);
998 	mutex_unlock(&info->lock);
999 }
1000 
1001 static int __restart_threaded_test(struct dmatest_info *info, bool run)
1002 {
1003 	struct dmatest_params *params = &info->params;
1004 
1005 	/* Stop any running test first */
1006 	__stop_threaded_test(info);
1007 
1008 	if (run == false)
1009 		return 0;
1010 
1011 	/* Clear results from previous run */
1012 	result_free(info, NULL);
1013 
1014 	/* Copy test parameters */
1015 	params->buf_size = test_buf_size;
1016 	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
1017 	strlcpy(params->device, strim(test_device), sizeof(params->device));
1018 	params->threads_per_chan = threads_per_chan;
1019 	params->max_channels = max_channels;
1020 	params->iterations = iterations;
1021 	params->xor_sources = xor_sources;
1022 	params->pq_sources = pq_sources;
1023 	params->timeout = timeout;
1024 
1025 	/* Run test with new parameters */
1026 	return __run_threaded_test(info);
1027 }
1028 
1029 static bool __is_threaded_test_run(struct dmatest_info *info)
1030 {
1031 	struct dmatest_chan *dtc;
1032 
1033 	list_for_each_entry(dtc, &info->channels, node) {
1034 		struct dmatest_thread *thread;
1035 
1036 		list_for_each_entry(thread, &dtc->threads, node) {
1037 			if (!thread->done)
1038 				return true;
1039 		}
1040 	}
1041 
1042 	return false;
1043 }
1044 
1045 static ssize_t dtf_read_run(struct file *file, char __user *user_buf,
1046 		size_t count, loff_t *ppos)
1047 {
1048 	struct dmatest_info *info = file->private_data;
1049 	char buf[3];
1050 
1051 	mutex_lock(&info->lock);
1052 
1053 	if (__is_threaded_test_run(info)) {
1054 		buf[0] = 'Y';
1055 	} else {
1056 		__stop_threaded_test(info);
1057 		buf[0] = 'N';
1058 	}
1059 
1060 	mutex_unlock(&info->lock);
1061 	buf[1] = '\n';
1062 	buf[2] = 0x00;
1063 	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
1064 }
1065 
1066 static ssize_t dtf_write_run(struct file *file, const char __user *user_buf,
1067 		size_t count, loff_t *ppos)
1068 {
1069 	struct dmatest_info *info = file->private_data;
1070 	char buf[16];
1071 	bool bv;
1072 	int ret = 0;
1073 
1074 	if (copy_from_user(buf, user_buf, min(count, (sizeof(buf) - 1))))
1075 		return -EFAULT;
1076 
1077 	if (strtobool(buf, &bv) == 0) {
1078 		mutex_lock(&info->lock);
1079 
1080 		if (__is_threaded_test_run(info))
1081 			ret = -EBUSY;
1082 		else
1083 			ret = __restart_threaded_test(info, bv);
1084 
1085 		mutex_unlock(&info->lock);
1086 	}
1087 
1088 	return ret ? ret : count;
1089 }
1090 
1091 static const struct file_operations dtf_run_fops = {
1092 	.read	= dtf_read_run,
1093 	.write	= dtf_write_run,
1094 	.open	= simple_open,
1095 	.llseek	= default_llseek,
1096 };
1097 
1098 static int dtf_results_show(struct seq_file *sf, void *data)
1099 {
1100 	struct dmatest_info *info = sf->private;
1101 	struct dmatest_result *result;
1102 	struct dmatest_thread_result *tr;
1103 	unsigned int i;
1104 
1105 	mutex_lock(&info->results_lock);
1106 	list_for_each_entry(result, &info->results, node) {
1107 		list_for_each_entry(tr, &result->results, node) {
1108 			seq_printf(sf, "%s\n",
1109 				thread_result_get(result->name, tr));
1110 			if (tr->type == DMATEST_ET_VERIFY_BUF) {
1111 				for (i = 0; i < tr->vr->error_count; i++) {
1112 					seq_printf(sf, "\t%s\n",
1113 						verify_result_get_one(tr->vr, i));
1114 				}
1115 			}
1116 		}
1117 	}
1118 
1119 	mutex_unlock(&info->results_lock);
1120 	return 0;
1121 }
1122 
1123 static int dtf_results_open(struct inode *inode, struct file *file)
1124 {
1125 	return single_open(file, dtf_results_show, inode->i_private);
1126 }
1127 
1128 static const struct file_operations dtf_results_fops = {
1129 	.open		= dtf_results_open,
1130 	.read		= seq_read,
1131 	.llseek		= seq_lseek,
1132 	.release	= single_release,
1133 };
1134 
1135 static int dmatest_register_dbgfs(struct dmatest_info *info)
1136 {
1137 	struct dentry *d;
1138 
1139 	d = debugfs_create_dir("dmatest", NULL);
1140 	if (IS_ERR(d))
1141 		return PTR_ERR(d);
1142 	if (!d)
1143 		goto err_root;
1144 
1145 	info->root = d;
1146 
1147 	/* Run or stop threaded test */
1148 	debugfs_create_file("run", S_IWUSR | S_IRUGO, info->root, info,
1149 			    &dtf_run_fops);
1150 
1151 	/* Results of test in progress */
1152 	debugfs_create_file("results", S_IRUGO, info->root, info,
1153 			    &dtf_results_fops);
1154 
1155 	return 0;
1156 
1157 err_root:
1158 	pr_err("dmatest: Failed to initialize debugfs\n");
1159 	return -ENOMEM;
1160 }
1161 
1162 static int __init dmatest_init(void)
1163 {
1164 	struct dmatest_info *info = &test_info;
1165 	int ret;
1166 
1167 	memset(info, 0, sizeof(*info));
1168 
1169 	mutex_init(&info->lock);
1170 	INIT_LIST_HEAD(&info->channels);
1171 
1172 	mutex_init(&info->results_lock);
1173 	INIT_LIST_HEAD(&info->results);
1174 
1175 	ret = dmatest_register_dbgfs(info);
1176 	if (ret)
1177 		return ret;
1178 
1179 #ifdef MODULE
1180 	return 0;
1181 #else
1182 	return run_threaded_test(info);
1183 #endif
1184 }
1185 /* when compiled-in wait for drivers to load first */
1186 late_initcall(dmatest_init);
1187 
1188 static void __exit dmatest_exit(void)
1189 {
1190 	struct dmatest_info *info = &test_info;
1191 
1192 	debugfs_remove_recursive(info->root);
1193 	stop_threaded_test(info);
1194 	result_free(info, NULL);
1195 }
1196 module_exit(dmatest_exit);
1197 
1198 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1199 MODULE_LICENSE("GPL v2");
1200