xref: /openbmc/linux/drivers/dma/dmatest.c (revision e9839402)
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/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/random.h>
22 #include <linux/slab.h>
23 #include <linux/wait.h>
24 
25 static unsigned int test_buf_size = 16384;
26 module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
27 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
28 
29 static char test_channel[20];
30 module_param_string(channel, test_channel, sizeof(test_channel),
31 		S_IRUGO | S_IWUSR);
32 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
33 
34 static char test_device[32];
35 module_param_string(device, test_device, sizeof(test_device),
36 		S_IRUGO | S_IWUSR);
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 | S_IWUSR);
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 | S_IWUSR);
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 | S_IWUSR);
51 MODULE_PARM_DESC(iterations,
52 		"Iterations before stopping test (default: infinite)");
53 
54 static unsigned int sg_buffers = 1;
55 module_param(sg_buffers, uint, S_IRUGO | S_IWUSR);
56 MODULE_PARM_DESC(sg_buffers,
57 		"Number of scatter gather buffers (default: 1)");
58 
59 static unsigned int dmatest;
60 module_param(dmatest, uint, S_IRUGO | S_IWUSR);
61 MODULE_PARM_DESC(dmatest,
62 		"dmatest 0-memcpy 1-slave_sg (default: 0)");
63 
64 static unsigned int xor_sources = 3;
65 module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
66 MODULE_PARM_DESC(xor_sources,
67 		"Number of xor source buffers (default: 3)");
68 
69 static unsigned int pq_sources = 3;
70 module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
71 MODULE_PARM_DESC(pq_sources,
72 		"Number of p+q source buffers (default: 3)");
73 
74 static int timeout = 3000;
75 module_param(timeout, uint, S_IRUGO | S_IWUSR);
76 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
77 		 "Pass -1 for infinite timeout");
78 
79 static bool noverify;
80 module_param(noverify, bool, S_IRUGO | S_IWUSR);
81 MODULE_PARM_DESC(noverify, "Disable random data setup and verification");
82 
83 static bool verbose;
84 module_param(verbose, bool, S_IRUGO | S_IWUSR);
85 MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
86 
87 /**
88  * struct dmatest_params - test parameters.
89  * @buf_size:		size of the memcpy test buffer
90  * @channel:		bus ID of the channel to test
91  * @device:		bus ID of the DMA Engine to test
92  * @threads_per_chan:	number of threads to start per channel
93  * @max_channels:	maximum number of channels to use
94  * @iterations:		iterations before stopping test
95  * @xor_sources:	number of xor source buffers
96  * @pq_sources:		number of p+q source buffers
97  * @timeout:		transfer timeout in msec, -1 for infinite timeout
98  */
99 struct dmatest_params {
100 	unsigned int	buf_size;
101 	char		channel[20];
102 	char		device[32];
103 	unsigned int	threads_per_chan;
104 	unsigned int	max_channels;
105 	unsigned int	iterations;
106 	unsigned int	xor_sources;
107 	unsigned int	pq_sources;
108 	int		timeout;
109 	bool		noverify;
110 };
111 
112 /**
113  * struct dmatest_info - test information.
114  * @params:		test parameters
115  * @lock:		access protection to the fields of this structure
116  */
117 static struct dmatest_info {
118 	/* Test parameters */
119 	struct dmatest_params	params;
120 
121 	/* Internal state */
122 	struct list_head	channels;
123 	unsigned int		nr_channels;
124 	struct mutex		lock;
125 	bool			did_init;
126 } test_info = {
127 	.channels = LIST_HEAD_INIT(test_info.channels),
128 	.lock = __MUTEX_INITIALIZER(test_info.lock),
129 };
130 
131 static int dmatest_run_set(const char *val, const struct kernel_param *kp);
132 static int dmatest_run_get(char *val, const struct kernel_param *kp);
133 static const struct kernel_param_ops run_ops = {
134 	.set = dmatest_run_set,
135 	.get = dmatest_run_get,
136 };
137 static bool dmatest_run;
138 module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
139 MODULE_PARM_DESC(run, "Run the test (default: false)");
140 
141 /* Maximum amount of mismatched bytes in buffer to print */
142 #define MAX_ERROR_COUNT		32
143 
144 /*
145  * Initialization patterns. All bytes in the source buffer has bit 7
146  * set, all bytes in the destination buffer has bit 7 cleared.
147  *
148  * Bit 6 is set for all bytes which are to be copied by the DMA
149  * engine. Bit 5 is set for all bytes which are to be overwritten by
150  * the DMA engine.
151  *
152  * The remaining bits are the inverse of a counter which increments by
153  * one for each byte address.
154  */
155 #define PATTERN_SRC		0x80
156 #define PATTERN_DST		0x00
157 #define PATTERN_COPY		0x40
158 #define PATTERN_OVERWRITE	0x20
159 #define PATTERN_COUNT_MASK	0x1f
160 
161 struct dmatest_thread {
162 	struct list_head	node;
163 	struct dmatest_info	*info;
164 	struct task_struct	*task;
165 	struct dma_chan		*chan;
166 	u8			**srcs;
167 	u8			**dsts;
168 	enum dma_transaction_type type;
169 	bool			done;
170 };
171 
172 struct dmatest_chan {
173 	struct list_head	node;
174 	struct dma_chan		*chan;
175 	struct list_head	threads;
176 };
177 
178 static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
179 static bool wait;
180 
181 static bool is_threaded_test_run(struct dmatest_info *info)
182 {
183 	struct dmatest_chan *dtc;
184 
185 	list_for_each_entry(dtc, &info->channels, node) {
186 		struct dmatest_thread *thread;
187 
188 		list_for_each_entry(thread, &dtc->threads, node) {
189 			if (!thread->done)
190 				return true;
191 		}
192 	}
193 
194 	return false;
195 }
196 
197 static int dmatest_wait_get(char *val, const struct kernel_param *kp)
198 {
199 	struct dmatest_info *info = &test_info;
200 	struct dmatest_params *params = &info->params;
201 
202 	if (params->iterations)
203 		wait_event(thread_wait, !is_threaded_test_run(info));
204 	wait = true;
205 	return param_get_bool(val, kp);
206 }
207 
208 static const struct kernel_param_ops wait_ops = {
209 	.get = dmatest_wait_get,
210 	.set = param_set_bool,
211 };
212 module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
213 MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
214 
215 static bool dmatest_match_channel(struct dmatest_params *params,
216 		struct dma_chan *chan)
217 {
218 	if (params->channel[0] == '\0')
219 		return true;
220 	return strcmp(dma_chan_name(chan), params->channel) == 0;
221 }
222 
223 static bool dmatest_match_device(struct dmatest_params *params,
224 		struct dma_device *device)
225 {
226 	if (params->device[0] == '\0')
227 		return true;
228 	return strcmp(dev_name(device->dev), params->device) == 0;
229 }
230 
231 static unsigned long dmatest_random(void)
232 {
233 	unsigned long buf;
234 
235 	prandom_bytes(&buf, sizeof(buf));
236 	return buf;
237 }
238 
239 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
240 		unsigned int buf_size)
241 {
242 	unsigned int i;
243 	u8 *buf;
244 
245 	for (; (buf = *bufs); bufs++) {
246 		for (i = 0; i < start; i++)
247 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
248 		for ( ; i < start + len; i++)
249 			buf[i] = PATTERN_SRC | PATTERN_COPY
250 				| (~i & PATTERN_COUNT_MASK);
251 		for ( ; i < buf_size; i++)
252 			buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK);
253 		buf++;
254 	}
255 }
256 
257 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
258 		unsigned int buf_size)
259 {
260 	unsigned int i;
261 	u8 *buf;
262 
263 	for (; (buf = *bufs); bufs++) {
264 		for (i = 0; i < start; i++)
265 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
266 		for ( ; i < start + len; i++)
267 			buf[i] = PATTERN_DST | PATTERN_OVERWRITE
268 				| (~i & PATTERN_COUNT_MASK);
269 		for ( ; i < buf_size; i++)
270 			buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK);
271 	}
272 }
273 
274 static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
275 		unsigned int counter, bool is_srcbuf)
276 {
277 	u8		diff = actual ^ pattern;
278 	u8		expected = pattern | (~counter & PATTERN_COUNT_MASK);
279 	const char	*thread_name = current->comm;
280 
281 	if (is_srcbuf)
282 		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
283 			thread_name, index, expected, actual);
284 	else if ((pattern & PATTERN_COPY)
285 			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
286 		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
287 			thread_name, index, expected, actual);
288 	else if (diff & PATTERN_SRC)
289 		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
290 			thread_name, index, expected, actual);
291 	else
292 		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
293 			thread_name, index, expected, actual);
294 }
295 
296 static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
297 		unsigned int end, unsigned int counter, u8 pattern,
298 		bool is_srcbuf)
299 {
300 	unsigned int i;
301 	unsigned int error_count = 0;
302 	u8 actual;
303 	u8 expected;
304 	u8 *buf;
305 	unsigned int counter_orig = counter;
306 
307 	for (; (buf = *bufs); bufs++) {
308 		counter = counter_orig;
309 		for (i = start; i < end; i++) {
310 			actual = buf[i];
311 			expected = pattern | (~counter & PATTERN_COUNT_MASK);
312 			if (actual != expected) {
313 				if (error_count < MAX_ERROR_COUNT)
314 					dmatest_mismatch(actual, pattern, i,
315 							 counter, is_srcbuf);
316 				error_count++;
317 			}
318 			counter++;
319 		}
320 	}
321 
322 	if (error_count > MAX_ERROR_COUNT)
323 		pr_warn("%s: %u errors suppressed\n",
324 			current->comm, error_count - MAX_ERROR_COUNT);
325 
326 	return error_count;
327 }
328 
329 /* poor man's completion - we want to use wait_event_freezable() on it */
330 struct dmatest_done {
331 	bool			done;
332 	wait_queue_head_t	*wait;
333 };
334 
335 static void dmatest_callback(void *arg)
336 {
337 	struct dmatest_done *done = arg;
338 
339 	done->done = true;
340 	wake_up_all(done->wait);
341 }
342 
343 static unsigned int min_odd(unsigned int x, unsigned int y)
344 {
345 	unsigned int val = min(x, y);
346 
347 	return val % 2 ? val : val - 1;
348 }
349 
350 static void result(const char *err, unsigned int n, unsigned int src_off,
351 		   unsigned int dst_off, unsigned int len, unsigned long data)
352 {
353 	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
354 		current->comm, n, err, src_off, dst_off, len, data);
355 }
356 
357 static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
358 		       unsigned int dst_off, unsigned int len,
359 		       unsigned long data)
360 {
361 	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
362 		 current->comm, n, err, src_off, dst_off, len, data);
363 }
364 
365 #define verbose_result(err, n, src_off, dst_off, len, data) ({	\
366 	if (verbose)						\
367 		result(err, n, src_off, dst_off, len, data);	\
368 	else							\
369 		dbg_result(err, n, src_off, dst_off, len, data);\
370 })
371 
372 static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
373 {
374 	unsigned long long per_sec = 1000000;
375 
376 	if (runtime <= 0)
377 		return 0;
378 
379 	/* drop precision until runtime is 32-bits */
380 	while (runtime > UINT_MAX) {
381 		runtime >>= 1;
382 		per_sec <<= 1;
383 	}
384 
385 	per_sec *= val;
386 	do_div(per_sec, runtime);
387 	return per_sec;
388 }
389 
390 static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
391 {
392 	return dmatest_persec(runtime, len >> 10);
393 }
394 
395 /*
396  * This function repeatedly tests DMA transfers of various lengths and
397  * offsets for a given operation type until it is told to exit by
398  * kthread_stop(). There may be multiple threads running this function
399  * in parallel for a single channel, and there may be multiple channels
400  * being tested in parallel.
401  *
402  * Before each test, the source and destination buffer is initialized
403  * with a known pattern. This pattern is different depending on
404  * whether it's in an area which is supposed to be copied or
405  * overwritten, and different in the source and destination buffers.
406  * So if the DMA engine doesn't copy exactly what we tell it to copy,
407  * we'll notice.
408  */
409 static int dmatest_func(void *data)
410 {
411 	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
412 	struct dmatest_thread	*thread = data;
413 	struct dmatest_done	done = { .wait = &done_wait };
414 	struct dmatest_info	*info;
415 	struct dmatest_params	*params;
416 	struct dma_chan		*chan;
417 	struct dma_device	*dev;
418 	unsigned int		error_count;
419 	unsigned int		failed_tests = 0;
420 	unsigned int		total_tests = 0;
421 	dma_cookie_t		cookie;
422 	enum dma_status		status;
423 	enum dma_ctrl_flags 	flags;
424 	u8			*pq_coefs = NULL;
425 	int			ret;
426 	int			src_cnt;
427 	int			dst_cnt;
428 	int			i;
429 	ktime_t			ktime, start, diff;
430 	ktime_t			filltime = ktime_set(0, 0);
431 	ktime_t			comparetime = ktime_set(0, 0);
432 	s64			runtime = 0;
433 	unsigned long long	total_len = 0;
434 
435 	set_freezable();
436 
437 	ret = -ENOMEM;
438 
439 	smp_rmb();
440 	info = thread->info;
441 	params = &info->params;
442 	chan = thread->chan;
443 	dev = chan->device;
444 	if (thread->type == DMA_MEMCPY)
445 		src_cnt = dst_cnt = 1;
446 	else if (thread->type == DMA_SG)
447 		src_cnt = dst_cnt = sg_buffers;
448 	else if (thread->type == DMA_XOR) {
449 		/* force odd to ensure dst = src */
450 		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
451 		dst_cnt = 1;
452 	} else if (thread->type == DMA_PQ) {
453 		/* force odd to ensure dst = src */
454 		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
455 		dst_cnt = 2;
456 
457 		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
458 		if (!pq_coefs)
459 			goto err_thread_type;
460 
461 		for (i = 0; i < src_cnt; i++)
462 			pq_coefs[i] = 1;
463 	} else
464 		goto err_thread_type;
465 
466 	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
467 	if (!thread->srcs)
468 		goto err_srcs;
469 	for (i = 0; i < src_cnt; i++) {
470 		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
471 		if (!thread->srcs[i])
472 			goto err_srcbuf;
473 	}
474 	thread->srcs[i] = NULL;
475 
476 	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
477 	if (!thread->dsts)
478 		goto err_dsts;
479 	for (i = 0; i < dst_cnt; i++) {
480 		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
481 		if (!thread->dsts[i])
482 			goto err_dstbuf;
483 	}
484 	thread->dsts[i] = NULL;
485 
486 	set_user_nice(current, 10);
487 
488 	/*
489 	 * src and dst buffers are freed by ourselves below
490 	 */
491 	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
492 
493 	ktime = ktime_get();
494 	while (!kthread_should_stop()
495 	       && !(params->iterations && total_tests >= params->iterations)) {
496 		struct dma_async_tx_descriptor *tx = NULL;
497 		struct dmaengine_unmap_data *um;
498 		dma_addr_t srcs[src_cnt];
499 		dma_addr_t *dsts;
500 		unsigned int src_off, dst_off, len;
501 		u8 align = 0;
502 		struct scatterlist tx_sg[src_cnt];
503 		struct scatterlist rx_sg[src_cnt];
504 
505 		total_tests++;
506 
507 		/* honor alignment restrictions */
508 		if (thread->type == DMA_MEMCPY || thread->type == DMA_SG)
509 			align = dev->copy_align;
510 		else if (thread->type == DMA_XOR)
511 			align = dev->xor_align;
512 		else if (thread->type == DMA_PQ)
513 			align = dev->pq_align;
514 
515 		if (1 << align > params->buf_size) {
516 			pr_err("%u-byte buffer too small for %d-byte alignment\n",
517 			       params->buf_size, 1 << align);
518 			break;
519 		}
520 
521 		if (params->noverify)
522 			len = params->buf_size;
523 		else
524 			len = dmatest_random() % params->buf_size + 1;
525 
526 		len = (len >> align) << align;
527 		if (!len)
528 			len = 1 << align;
529 
530 		total_len += len;
531 
532 		if (params->noverify) {
533 			src_off = 0;
534 			dst_off = 0;
535 		} else {
536 			start = ktime_get();
537 			src_off = dmatest_random() % (params->buf_size - len + 1);
538 			dst_off = dmatest_random() % (params->buf_size - len + 1);
539 
540 			src_off = (src_off >> align) << align;
541 			dst_off = (dst_off >> align) << align;
542 
543 			dmatest_init_srcs(thread->srcs, src_off, len,
544 					  params->buf_size);
545 			dmatest_init_dsts(thread->dsts, dst_off, len,
546 					  params->buf_size);
547 
548 			diff = ktime_sub(ktime_get(), start);
549 			filltime = ktime_add(filltime, diff);
550 		}
551 
552 		um = dmaengine_get_unmap_data(dev->dev, src_cnt+dst_cnt,
553 					      GFP_KERNEL);
554 		if (!um) {
555 			failed_tests++;
556 			result("unmap data NULL", total_tests,
557 			       src_off, dst_off, len, ret);
558 			continue;
559 		}
560 
561 		um->len = params->buf_size;
562 		for (i = 0; i < src_cnt; i++) {
563 			void *buf = thread->srcs[i];
564 			struct page *pg = virt_to_page(buf);
565 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
566 
567 			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
568 						   um->len, DMA_TO_DEVICE);
569 			srcs[i] = um->addr[i] + src_off;
570 			ret = dma_mapping_error(dev->dev, um->addr[i]);
571 			if (ret) {
572 				dmaengine_unmap_put(um);
573 				result("src mapping error", total_tests,
574 				       src_off, dst_off, len, ret);
575 				failed_tests++;
576 				continue;
577 			}
578 			um->to_cnt++;
579 		}
580 		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
581 		dsts = &um->addr[src_cnt];
582 		for (i = 0; i < dst_cnt; i++) {
583 			void *buf = thread->dsts[i];
584 			struct page *pg = virt_to_page(buf);
585 			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
586 
587 			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
588 					       DMA_BIDIRECTIONAL);
589 			ret = dma_mapping_error(dev->dev, dsts[i]);
590 			if (ret) {
591 				dmaengine_unmap_put(um);
592 				result("dst mapping error", total_tests,
593 				       src_off, dst_off, len, ret);
594 				failed_tests++;
595 				continue;
596 			}
597 			um->bidi_cnt++;
598 		}
599 
600 		sg_init_table(tx_sg, src_cnt);
601 		sg_init_table(rx_sg, src_cnt);
602 		for (i = 0; i < src_cnt; i++) {
603 			sg_dma_address(&rx_sg[i]) = srcs[i];
604 			sg_dma_address(&tx_sg[i]) = dsts[i] + dst_off;
605 			sg_dma_len(&tx_sg[i]) = len;
606 			sg_dma_len(&rx_sg[i]) = len;
607 		}
608 
609 		if (thread->type == DMA_MEMCPY)
610 			tx = dev->device_prep_dma_memcpy(chan,
611 							 dsts[0] + dst_off,
612 							 srcs[0], len, flags);
613 		else if (thread->type == DMA_SG)
614 			tx = dev->device_prep_dma_sg(chan, tx_sg, src_cnt,
615 						     rx_sg, src_cnt, flags);
616 		else if (thread->type == DMA_XOR)
617 			tx = dev->device_prep_dma_xor(chan,
618 						      dsts[0] + dst_off,
619 						      srcs, src_cnt,
620 						      len, flags);
621 		else if (thread->type == DMA_PQ) {
622 			dma_addr_t dma_pq[dst_cnt];
623 
624 			for (i = 0; i < dst_cnt; i++)
625 				dma_pq[i] = dsts[i] + dst_off;
626 			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
627 						     src_cnt, pq_coefs,
628 						     len, flags);
629 		}
630 
631 		if (!tx) {
632 			dmaengine_unmap_put(um);
633 			result("prep error", total_tests, src_off,
634 			       dst_off, len, ret);
635 			msleep(100);
636 			failed_tests++;
637 			continue;
638 		}
639 
640 		done.done = false;
641 		tx->callback = dmatest_callback;
642 		tx->callback_param = &done;
643 		cookie = tx->tx_submit(tx);
644 
645 		if (dma_submit_error(cookie)) {
646 			dmaengine_unmap_put(um);
647 			result("submit error", total_tests, src_off,
648 			       dst_off, len, ret);
649 			msleep(100);
650 			failed_tests++;
651 			continue;
652 		}
653 		dma_async_issue_pending(chan);
654 
655 		wait_event_freezable_timeout(done_wait, done.done,
656 					     msecs_to_jiffies(params->timeout));
657 
658 		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
659 
660 		if (!done.done) {
661 			/*
662 			 * We're leaving the timed out dma operation with
663 			 * dangling pointer to done_wait.  To make this
664 			 * correct, we'll need to allocate wait_done for
665 			 * each test iteration and perform "who's gonna
666 			 * free it this time?" dancing.  For now, just
667 			 * leave it dangling.
668 			 */
669 			dmaengine_unmap_put(um);
670 			result("test timed out", total_tests, src_off, dst_off,
671 			       len, 0);
672 			failed_tests++;
673 			continue;
674 		} else if (status != DMA_COMPLETE) {
675 			dmaengine_unmap_put(um);
676 			result(status == DMA_ERROR ?
677 			       "completion error status" :
678 			       "completion busy status", total_tests, src_off,
679 			       dst_off, len, ret);
680 			failed_tests++;
681 			continue;
682 		}
683 
684 		dmaengine_unmap_put(um);
685 
686 		if (params->noverify) {
687 			verbose_result("test passed", total_tests, src_off,
688 				       dst_off, len, 0);
689 			continue;
690 		}
691 
692 		start = ktime_get();
693 		pr_debug("%s: verifying source buffer...\n", current->comm);
694 		error_count = dmatest_verify(thread->srcs, 0, src_off,
695 				0, PATTERN_SRC, true);
696 		error_count += dmatest_verify(thread->srcs, src_off,
697 				src_off + len, src_off,
698 				PATTERN_SRC | PATTERN_COPY, true);
699 		error_count += dmatest_verify(thread->srcs, src_off + len,
700 				params->buf_size, src_off + len,
701 				PATTERN_SRC, true);
702 
703 		pr_debug("%s: verifying dest buffer...\n", current->comm);
704 		error_count += dmatest_verify(thread->dsts, 0, dst_off,
705 				0, PATTERN_DST, false);
706 		error_count += dmatest_verify(thread->dsts, dst_off,
707 				dst_off + len, src_off,
708 				PATTERN_SRC | PATTERN_COPY, false);
709 		error_count += dmatest_verify(thread->dsts, dst_off + len,
710 				params->buf_size, dst_off + len,
711 				PATTERN_DST, false);
712 
713 		diff = ktime_sub(ktime_get(), start);
714 		comparetime = ktime_add(comparetime, diff);
715 
716 		if (error_count) {
717 			result("data error", total_tests, src_off, dst_off,
718 			       len, error_count);
719 			failed_tests++;
720 		} else {
721 			verbose_result("test passed", total_tests, src_off,
722 				       dst_off, len, 0);
723 		}
724 	}
725 	ktime = ktime_sub(ktime_get(), ktime);
726 	ktime = ktime_sub(ktime, comparetime);
727 	ktime = ktime_sub(ktime, filltime);
728 	runtime = ktime_to_us(ktime);
729 
730 	ret = 0;
731 err_dstbuf:
732 	for (i = 0; thread->dsts[i]; i++)
733 		kfree(thread->dsts[i]);
734 	kfree(thread->dsts);
735 err_dsts:
736 err_srcbuf:
737 	for (i = 0; thread->srcs[i]; i++)
738 		kfree(thread->srcs[i]);
739 	kfree(thread->srcs);
740 err_srcs:
741 	kfree(pq_coefs);
742 err_thread_type:
743 	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
744 		current->comm, total_tests, failed_tests,
745 		dmatest_persec(runtime, total_tests),
746 		dmatest_KBs(runtime, total_len), ret);
747 
748 	/* terminate all transfers on specified channels */
749 	if (ret)
750 		dmaengine_terminate_all(chan);
751 
752 	thread->done = true;
753 	wake_up(&thread_wait);
754 
755 	return ret;
756 }
757 
758 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
759 {
760 	struct dmatest_thread	*thread;
761 	struct dmatest_thread	*_thread;
762 	int			ret;
763 
764 	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
765 		ret = kthread_stop(thread->task);
766 		pr_debug("thread %s exited with status %d\n",
767 			 thread->task->comm, ret);
768 		list_del(&thread->node);
769 		put_task_struct(thread->task);
770 		kfree(thread);
771 	}
772 
773 	/* terminate all transfers on specified channels */
774 	dmaengine_terminate_all(dtc->chan);
775 
776 	kfree(dtc);
777 }
778 
779 static int dmatest_add_threads(struct dmatest_info *info,
780 		struct dmatest_chan *dtc, enum dma_transaction_type type)
781 {
782 	struct dmatest_params *params = &info->params;
783 	struct dmatest_thread *thread;
784 	struct dma_chan *chan = dtc->chan;
785 	char *op;
786 	unsigned int i;
787 
788 	if (type == DMA_MEMCPY)
789 		op = "copy";
790 	else if (type == DMA_SG)
791 		op = "sg";
792 	else if (type == DMA_XOR)
793 		op = "xor";
794 	else if (type == DMA_PQ)
795 		op = "pq";
796 	else
797 		return -EINVAL;
798 
799 	for (i = 0; i < params->threads_per_chan; i++) {
800 		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
801 		if (!thread) {
802 			pr_warn("No memory for %s-%s%u\n",
803 				dma_chan_name(chan), op, i);
804 			break;
805 		}
806 		thread->info = info;
807 		thread->chan = dtc->chan;
808 		thread->type = type;
809 		smp_wmb();
810 		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
811 				dma_chan_name(chan), op, i);
812 		if (IS_ERR(thread->task)) {
813 			pr_warn("Failed to create thread %s-%s%u\n",
814 				dma_chan_name(chan), op, i);
815 			kfree(thread);
816 			break;
817 		}
818 
819 		/* srcbuf and dstbuf are allocated by the thread itself */
820 		get_task_struct(thread->task);
821 		list_add_tail(&thread->node, &dtc->threads);
822 		wake_up_process(thread->task);
823 	}
824 
825 	return i;
826 }
827 
828 static int dmatest_add_channel(struct dmatest_info *info,
829 		struct dma_chan *chan)
830 {
831 	struct dmatest_chan	*dtc;
832 	struct dma_device	*dma_dev = chan->device;
833 	unsigned int		thread_count = 0;
834 	int cnt;
835 
836 	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
837 	if (!dtc) {
838 		pr_warn("No memory for %s\n", dma_chan_name(chan));
839 		return -ENOMEM;
840 	}
841 
842 	dtc->chan = chan;
843 	INIT_LIST_HEAD(&dtc->threads);
844 
845 	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
846 		if (dmatest == 0) {
847 			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
848 			thread_count += cnt > 0 ? cnt : 0;
849 		}
850 	}
851 
852 	if (dma_has_cap(DMA_SG, dma_dev->cap_mask)) {
853 		if (dmatest == 1) {
854 			cnt = dmatest_add_threads(info, dtc, DMA_SG);
855 			thread_count += cnt > 0 ? cnt : 0;
856 		}
857 	}
858 
859 	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
860 		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
861 		thread_count += cnt > 0 ? cnt : 0;
862 	}
863 	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
864 		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
865 		thread_count += cnt > 0 ? cnt : 0;
866 	}
867 
868 	pr_info("Started %u threads using %s\n",
869 		thread_count, dma_chan_name(chan));
870 
871 	list_add_tail(&dtc->node, &info->channels);
872 	info->nr_channels++;
873 
874 	return 0;
875 }
876 
877 static bool filter(struct dma_chan *chan, void *param)
878 {
879 	struct dmatest_params *params = param;
880 
881 	if (!dmatest_match_channel(params, chan) ||
882 	    !dmatest_match_device(params, chan->device))
883 		return false;
884 	else
885 		return true;
886 }
887 
888 static void request_channels(struct dmatest_info *info,
889 			     enum dma_transaction_type type)
890 {
891 	dma_cap_mask_t mask;
892 
893 	dma_cap_zero(mask);
894 	dma_cap_set(type, mask);
895 	for (;;) {
896 		struct dmatest_params *params = &info->params;
897 		struct dma_chan *chan;
898 
899 		chan = dma_request_channel(mask, filter, params);
900 		if (chan) {
901 			if (dmatest_add_channel(info, chan)) {
902 				dma_release_channel(chan);
903 				break; /* add_channel failed, punt */
904 			}
905 		} else
906 			break; /* no more channels available */
907 		if (params->max_channels &&
908 		    info->nr_channels >= params->max_channels)
909 			break; /* we have all we need */
910 	}
911 }
912 
913 static void run_threaded_test(struct dmatest_info *info)
914 {
915 	struct dmatest_params *params = &info->params;
916 
917 	/* Copy test parameters */
918 	params->buf_size = test_buf_size;
919 	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
920 	strlcpy(params->device, strim(test_device), sizeof(params->device));
921 	params->threads_per_chan = threads_per_chan;
922 	params->max_channels = max_channels;
923 	params->iterations = iterations;
924 	params->xor_sources = xor_sources;
925 	params->pq_sources = pq_sources;
926 	params->timeout = timeout;
927 	params->noverify = noverify;
928 
929 	request_channels(info, DMA_MEMCPY);
930 	request_channels(info, DMA_XOR);
931 	request_channels(info, DMA_SG);
932 	request_channels(info, DMA_PQ);
933 }
934 
935 static void stop_threaded_test(struct dmatest_info *info)
936 {
937 	struct dmatest_chan *dtc, *_dtc;
938 	struct dma_chan *chan;
939 
940 	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
941 		list_del(&dtc->node);
942 		chan = dtc->chan;
943 		dmatest_cleanup_channel(dtc);
944 		pr_debug("dropped channel %s\n", dma_chan_name(chan));
945 		dma_release_channel(chan);
946 	}
947 
948 	info->nr_channels = 0;
949 }
950 
951 static void restart_threaded_test(struct dmatest_info *info, bool run)
952 {
953 	/* we might be called early to set run=, defer running until all
954 	 * parameters have been evaluated
955 	 */
956 	if (!info->did_init)
957 		return;
958 
959 	/* Stop any running test first */
960 	stop_threaded_test(info);
961 
962 	/* Run test with new parameters */
963 	run_threaded_test(info);
964 }
965 
966 static int dmatest_run_get(char *val, const struct kernel_param *kp)
967 {
968 	struct dmatest_info *info = &test_info;
969 
970 	mutex_lock(&info->lock);
971 	if (is_threaded_test_run(info)) {
972 		dmatest_run = true;
973 	} else {
974 		stop_threaded_test(info);
975 		dmatest_run = false;
976 	}
977 	mutex_unlock(&info->lock);
978 
979 	return param_get_bool(val, kp);
980 }
981 
982 static int dmatest_run_set(const char *val, const struct kernel_param *kp)
983 {
984 	struct dmatest_info *info = &test_info;
985 	int ret;
986 
987 	mutex_lock(&info->lock);
988 	ret = param_set_bool(val, kp);
989 	if (ret) {
990 		mutex_unlock(&info->lock);
991 		return ret;
992 	}
993 
994 	if (is_threaded_test_run(info))
995 		ret = -EBUSY;
996 	else if (dmatest_run)
997 		restart_threaded_test(info, dmatest_run);
998 
999 	mutex_unlock(&info->lock);
1000 
1001 	return ret;
1002 }
1003 
1004 static int __init dmatest_init(void)
1005 {
1006 	struct dmatest_info *info = &test_info;
1007 	struct dmatest_params *params = &info->params;
1008 
1009 	if (dmatest_run) {
1010 		mutex_lock(&info->lock);
1011 		run_threaded_test(info);
1012 		mutex_unlock(&info->lock);
1013 	}
1014 
1015 	if (params->iterations && wait)
1016 		wait_event(thread_wait, !is_threaded_test_run(info));
1017 
1018 	/* module parameters are stable, inittime tests are started,
1019 	 * let userspace take over 'run' control
1020 	 */
1021 	info->did_init = true;
1022 
1023 	return 0;
1024 }
1025 /* when compiled-in wait for drivers to load first */
1026 late_initcall(dmatest_init);
1027 
1028 static void __exit dmatest_exit(void)
1029 {
1030 	struct dmatest_info *info = &test_info;
1031 
1032 	mutex_lock(&info->lock);
1033 	stop_threaded_test(info);
1034 	mutex_unlock(&info->lock);
1035 }
1036 module_exit(dmatest_exit);
1037 
1038 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1039 MODULE_LICENSE("GPL v2");
1040