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  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
 25static unsigned int test_buf_size = 16384;
 26module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
 27MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
 28
 29static char test_channel[20];
 30module_param_string(channel, test_channel, sizeof(test_channel),
 31		S_IRUGO | S_IWUSR);
 32MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
 33
 34static char test_device[32];
 35module_param_string(device, test_device, sizeof(test_device),
 36		S_IRUGO | S_IWUSR);
 37MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
 38
 39static unsigned int threads_per_chan = 1;
 40module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
 41MODULE_PARM_DESC(threads_per_chan,
 42		"Number of threads to start per channel (default: 1)");
 43
 44static unsigned int max_channels;
 45module_param(max_channels, uint, S_IRUGO | S_IWUSR);
 46MODULE_PARM_DESC(max_channels,
 47		"Maximum number of channels to use (default: all)");
 48
 49static unsigned int iterations;
 50module_param(iterations, uint, S_IRUGO | S_IWUSR);
 51MODULE_PARM_DESC(iterations,
 52		"Iterations before stopping test (default: infinite)");
 53
 54static unsigned int xor_sources = 3;
 55module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
 56MODULE_PARM_DESC(xor_sources,
 57		"Number of xor source buffers (default: 3)");
 58
 59static unsigned int pq_sources = 3;
 60module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
 61MODULE_PARM_DESC(pq_sources,
 62		"Number of p+q source buffers (default: 3)");
 63
 64static int timeout = 3000;
 65module_param(timeout, uint, S_IRUGO | S_IWUSR);
 66MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
 67		 "Pass -1 for infinite timeout");
 68
 69static bool noverify;
 70module_param(noverify, bool, S_IRUGO | S_IWUSR);
 71MODULE_PARM_DESC(noverify, "Disable random data setup and verification");
 72
 73static bool verbose;
 74module_param(verbose, bool, S_IRUGO | S_IWUSR);
 75MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
 76
 77/**
 78 * struct dmatest_params - test parameters.
 79 * @buf_size:		size of the memcpy test buffer
 80 * @channel:		bus ID of the channel to test
 81 * @device:		bus ID of the DMA Engine to test
 82 * @threads_per_chan:	number of threads to start per channel
 83 * @max_channels:	maximum number of channels to use
 84 * @iterations:		iterations before stopping test
 85 * @xor_sources:	number of xor source buffers
 86 * @pq_sources:		number of p+q source buffers
 87 * @timeout:		transfer timeout in msec, -1 for infinite timeout
 88 */
 89struct dmatest_params {
 90	unsigned int	buf_size;
 91	char		channel[20];
 92	char		device[32];
 93	unsigned int	threads_per_chan;
 94	unsigned int	max_channels;
 95	unsigned int	iterations;
 96	unsigned int	xor_sources;
 97	unsigned int	pq_sources;
 98	int		timeout;
 99	bool		noverify;
100};
101
102/**
103 * struct dmatest_info - test information.
104 * @params:		test parameters
105 * @lock:		access protection to the fields of this structure
106 */
107static struct dmatest_info {
108	/* Test parameters */
109	struct dmatest_params	params;
110
111	/* Internal state */
112	struct list_head	channels;
113	unsigned int		nr_channels;
114	struct mutex		lock;
115	bool			did_init;
116} test_info = {
117	.channels = LIST_HEAD_INIT(test_info.channels),
118	.lock = __MUTEX_INITIALIZER(test_info.lock),
119};
120
121static int dmatest_run_set(const char *val, const struct kernel_param *kp);
122static int dmatest_run_get(char *val, const struct kernel_param *kp);
123static struct kernel_param_ops run_ops = {
124	.set = dmatest_run_set,
125	.get = dmatest_run_get,
126};
127static bool dmatest_run;
128module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
129MODULE_PARM_DESC(run, "Run the test (default: false)");
130
131/* Maximum amount of mismatched bytes in buffer to print */
132#define MAX_ERROR_COUNT		32
133
134/*
135 * Initialization patterns. All bytes in the source buffer has bit 7
136 * set, all bytes in the destination buffer has bit 7 cleared.
137 *
138 * Bit 6 is set for all bytes which are to be copied by the DMA
139 * engine. Bit 5 is set for all bytes which are to be overwritten by
140 * the DMA engine.
141 *
142 * The remaining bits are the inverse of a counter which increments by
143 * one for each byte address.
144 */
145#define PATTERN_SRC		0x80
146#define PATTERN_DST		0x00
147#define PATTERN_COPY		0x40
148#define PATTERN_OVERWRITE	0x20
149#define PATTERN_COUNT_MASK	0x1f
150
151struct dmatest_thread {
152	struct list_head	node;
153	struct dmatest_info	*info;
154	struct task_struct	*task;
155	struct dma_chan		*chan;
156	u8			**srcs;
157	u8			**dsts;
158	enum dma_transaction_type type;
159	bool			done;
160};
161
162struct dmatest_chan {
163	struct list_head	node;
164	struct dma_chan		*chan;
165	struct list_head	threads;
166};
167
168static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
169static bool wait;
170
171static bool is_threaded_test_run(struct dmatest_info *info)
172{
173	struct dmatest_chan *dtc;
174
175	list_for_each_entry(dtc, &info->channels, node) {
176		struct dmatest_thread *thread;
177
178		list_for_each_entry(thread, &dtc->threads, node) {
179			if (!thread->done)
180				return true;
181		}
182	}
183
184	return false;
185}
186
187static int dmatest_wait_get(char *val, const struct kernel_param *kp)
188{
189	struct dmatest_info *info = &test_info;
190	struct dmatest_params *params = &info->params;
191
192	if (params->iterations)
193		wait_event(thread_wait, !is_threaded_test_run(info));
194	wait = true;
195	return param_get_bool(val, kp);
196}
197
198static struct kernel_param_ops wait_ops = {
199	.get = dmatest_wait_get,
200	.set = param_set_bool,
201};
202module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
203MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
204
205static 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
213static 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
221static unsigned long dmatest_random(void)
222{
223	unsigned long buf;
224
225	prandom_bytes(&buf, sizeof(buf));
226	return buf;
227}
228
229static 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
247static 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
264static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
265		unsigned int counter, bool is_srcbuf)
266{
267	u8		diff = actual ^ pattern;
268	u8		expected = pattern | (~counter & PATTERN_COUNT_MASK);
269	const char	*thread_name = current->comm;
270
271	if (is_srcbuf)
272		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
273			thread_name, index, expected, actual);
274	else if ((pattern & PATTERN_COPY)
275			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
276		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
277			thread_name, index, expected, actual);
278	else if (diff & PATTERN_SRC)
279		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
280			thread_name, index, expected, actual);
281	else
282		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
283			thread_name, index, expected, actual);
284}
285
286static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
287		unsigned int end, unsigned int counter, u8 pattern,
288		bool is_srcbuf)
289{
290	unsigned int i;
291	unsigned int error_count = 0;
292	u8 actual;
293	u8 expected;
294	u8 *buf;
295	unsigned int counter_orig = counter;
296
297	for (; (buf = *bufs); bufs++) {
298		counter = counter_orig;
299		for (i = start; i < end; i++) {
300			actual = buf[i];
301			expected = pattern | (~counter & PATTERN_COUNT_MASK);
302			if (actual != expected) {
303				if (error_count < MAX_ERROR_COUNT)
304					dmatest_mismatch(actual, pattern, i,
305							 counter, is_srcbuf);
306				error_count++;
307			}
308			counter++;
309		}
310	}
311
312	if (error_count > MAX_ERROR_COUNT)
313		pr_warn("%s: %u errors suppressed\n",
314			current->comm, error_count - MAX_ERROR_COUNT);
315
316	return error_count;
317}
318
319/* poor man's completion - we want to use wait_event_freezable() on it */
320struct dmatest_done {
321	bool			done;
322	wait_queue_head_t	*wait;
323};
324
325static void dmatest_callback(void *arg)
326{
327	struct dmatest_done *done = arg;
328
329	done->done = true;
330	wake_up_all(done->wait);
331}
332
333static unsigned int min_odd(unsigned int x, unsigned int y)
334{
335	unsigned int val = min(x, y);
336
337	return val % 2 ? val : val - 1;
338}
339
340static void result(const char *err, unsigned int n, unsigned int src_off,
341		   unsigned int dst_off, unsigned int len, unsigned long data)
342{
343	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
344		current->comm, n, err, src_off, dst_off, len, data);
345}
346
347static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
348		       unsigned int dst_off, unsigned int len,
349		       unsigned long data)
350{
351	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
352		   current->comm, n, err, src_off, dst_off, len, data);
353}
354
355#define verbose_result(err, n, src_off, dst_off, len, data) ({ \
356	if (verbose) \
357		result(err, n, src_off, dst_off, len, data); \
358	else \
359		dbg_result(err, n, src_off, dst_off, len, data); \
360})
361
362static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
363{
364	unsigned long long per_sec = 1000000;
365
366	if (runtime <= 0)
367		return 0;
368
369	/* drop precision until runtime is 32-bits */
370	while (runtime > UINT_MAX) {
371		runtime >>= 1;
372		per_sec <<= 1;
373	}
374
375	per_sec *= val;
376	do_div(per_sec, runtime);
377	return per_sec;
378}
379
380static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
381{
382	return dmatest_persec(runtime, len >> 10);
383}
384
385/*
386 * This function repeatedly tests DMA transfers of various lengths and
387 * offsets for a given operation type until it is told to exit by
388 * kthread_stop(). There may be multiple threads running this function
389 * in parallel for a single channel, and there may be multiple channels
390 * being tested in parallel.
391 *
392 * Before each test, the source and destination buffer is initialized
393 * with a known pattern. This pattern is different depending on
394 * whether it's in an area which is supposed to be copied or
395 * overwritten, and different in the source and destination buffers.
396 * So if the DMA engine doesn't copy exactly what we tell it to copy,
397 * we'll notice.
398 */
399static int dmatest_func(void *data)
400{
401	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_wait);
402	struct dmatest_thread	*thread = data;
403	struct dmatest_done	done = { .wait = &done_wait };
404	struct dmatest_info	*info;
405	struct dmatest_params	*params;
406	struct dma_chan		*chan;
407	struct dma_device	*dev;
408	unsigned int		src_off, dst_off, len;
409	unsigned int		error_count;
410	unsigned int		failed_tests = 0;
411	unsigned int		total_tests = 0;
412	dma_cookie_t		cookie;
413	enum dma_status		status;
414	enum dma_ctrl_flags 	flags;
415	u8			*pq_coefs = NULL;
416	int			ret;
417	int			src_cnt;
418	int			dst_cnt;
419	int			i;
420	ktime_t			ktime;
421	s64			runtime = 0;
422	unsigned long long	total_len = 0;
423
424	set_freezable();
425
426	ret = -ENOMEM;
427
428	smp_rmb();
429	info = thread->info;
430	params = &info->params;
431	chan = thread->chan;
432	dev = chan->device;
433	if (thread->type == DMA_MEMCPY)
434		src_cnt = dst_cnt = 1;
435	else if (thread->type == DMA_XOR) {
436		/* force odd to ensure dst = src */
437		src_cnt = min_odd(params->xor_sources | 1, dev->max_xor);
438		dst_cnt = 1;
439	} else if (thread->type == DMA_PQ) {
440		/* force odd to ensure dst = src */
441		src_cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
442		dst_cnt = 2;
443
444		pq_coefs = kmalloc(params->pq_sources+1, GFP_KERNEL);
445		if (!pq_coefs)
446			goto err_thread_type;
447
448		for (i = 0; i < src_cnt; i++)
449			pq_coefs[i] = 1;
450	} else
451		goto err_thread_type;
452
453	thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL);
454	if (!thread->srcs)
455		goto err_srcs;
456	for (i = 0; i < src_cnt; i++) {
457		thread->srcs[i] = kmalloc(params->buf_size, GFP_KERNEL);
458		if (!thread->srcs[i])
459			goto err_srcbuf;
460	}
461	thread->srcs[i] = NULL;
462
463	thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL);
464	if (!thread->dsts)
465		goto err_dsts;
466	for (i = 0; i < dst_cnt; i++) {
467		thread->dsts[i] = kmalloc(params->buf_size, GFP_KERNEL);
468		if (!thread->dsts[i])
469			goto err_dstbuf;
470	}
471	thread->dsts[i] = NULL;
472
473	set_user_nice(current, 10);
474
475	/*
476	 * src and dst buffers are freed by ourselves below
477	 */
478	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
479
480	ktime = ktime_get();
481	while (!kthread_should_stop()
482	       && !(params->iterations && total_tests >= params->iterations)) {
483		struct dma_async_tx_descriptor *tx = NULL;
484		struct dmaengine_unmap_data *um;
485		dma_addr_t srcs[src_cnt];
486		dma_addr_t *dsts;
487		u8 align = 0;
488
489		total_tests++;
490
491		/* honor alignment restrictions */
492		if (thread->type == DMA_MEMCPY)
493			align = dev->copy_align;
494		else if (thread->type == DMA_XOR)
495			align = dev->xor_align;
496		else if (thread->type == DMA_PQ)
497			align = dev->pq_align;
498
499		if (1 << align > params->buf_size) {
500			pr_err("%u-byte buffer too small for %d-byte alignment\n",
501			       params->buf_size, 1 << align);
502			break;
503		}
504
505		if (params->noverify) {
506			len = params->buf_size;
507			src_off = 0;
508			dst_off = 0;
509		} else {
510			len = dmatest_random() % params->buf_size + 1;
511			len = (len >> align) << align;
512			if (!len)
513				len = 1 << align;
514			src_off = dmatest_random() % (params->buf_size - len + 1);
515			dst_off = dmatest_random() % (params->buf_size - len + 1);
516
517			src_off = (src_off >> align) << align;
518			dst_off = (dst_off >> align) << align;
519
520			dmatest_init_srcs(thread->srcs, src_off, len,
521					  params->buf_size);
522			dmatest_init_dsts(thread->dsts, dst_off, len,
523					  params->buf_size);
524		}
525
526		len = (len >> align) << align;
527		if (!len)
528			len = 1 << align;
529		total_len += len;
530
531		um = dmaengine_get_unmap_data(dev->dev, src_cnt+dst_cnt,
532					      GFP_KERNEL);
533		if (!um) {
534			failed_tests++;
535			result("unmap data NULL", total_tests,
536			       src_off, dst_off, len, ret);
537			continue;
538		}
539
540		um->len = params->buf_size;
541		for (i = 0; i < src_cnt; i++) {
542			void *buf = thread->srcs[i];
543			struct page *pg = virt_to_page(buf);
544			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
545
546			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
547						   um->len, DMA_TO_DEVICE);
548			srcs[i] = um->addr[i] + src_off;
549			ret = dma_mapping_error(dev->dev, um->addr[i]);
550			if (ret) {
551				dmaengine_unmap_put(um);
552				result("src mapping error", total_tests,
553				       src_off, dst_off, len, ret);
554				failed_tests++;
555				continue;
556			}
557			um->to_cnt++;
558		}
559		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
560		dsts = &um->addr[src_cnt];
561		for (i = 0; i < dst_cnt; i++) {
562			void *buf = thread->dsts[i];
563			struct page *pg = virt_to_page(buf);
564			unsigned pg_off = (unsigned long) buf & ~PAGE_MASK;
565
566			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
567					       DMA_BIDIRECTIONAL);
568			ret = dma_mapping_error(dev->dev, dsts[i]);
569			if (ret) {
570				dmaengine_unmap_put(um);
571				result("dst mapping error", total_tests,
572				       src_off, dst_off, len, ret);
573				failed_tests++;
574				continue;
575			}
576			um->bidi_cnt++;
577		}
578
579		if (thread->type == DMA_MEMCPY)
580			tx = dev->device_prep_dma_memcpy(chan,
581							 dsts[0] + dst_off,
582							 srcs[0], len, flags);
583		else if (thread->type == DMA_XOR)
584			tx = dev->device_prep_dma_xor(chan,
585						      dsts[0] + dst_off,
586						      srcs, src_cnt,
587						      len, flags);
588		else if (thread->type == DMA_PQ) {
589			dma_addr_t dma_pq[dst_cnt];
590
591			for (i = 0; i < dst_cnt; i++)
592				dma_pq[i] = dsts[i] + dst_off;
593			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
594						     src_cnt, pq_coefs,
595						     len, flags);
596		}
597
598		if (!tx) {
599			dmaengine_unmap_put(um);
600			result("prep error", total_tests, src_off,
601			       dst_off, len, ret);
602			msleep(100);
603			failed_tests++;
604			continue;
605		}
606
607		done.done = false;
608		tx->callback = dmatest_callback;
609		tx->callback_param = &done;
610		cookie = tx->tx_submit(tx);
611
612		if (dma_submit_error(cookie)) {
613			dmaengine_unmap_put(um);
614			result("submit error", total_tests, src_off,
615			       dst_off, len, ret);
616			msleep(100);
617			failed_tests++;
618			continue;
619		}
620		dma_async_issue_pending(chan);
621
622		wait_event_freezable_timeout(done_wait, done.done,
623					     msecs_to_jiffies(params->timeout));
624
625		status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
626
627		if (!done.done) {
628			/*
629			 * We're leaving the timed out dma operation with
630			 * dangling pointer to done_wait.  To make this
631			 * correct, we'll need to allocate wait_done for
632			 * each test iteration and perform "who's gonna
633			 * free it this time?" dancing.  For now, just
634			 * leave it dangling.
635			 */
636			dmaengine_unmap_put(um);
637			result("test timed out", total_tests, src_off, dst_off,
638			       len, 0);
639			failed_tests++;
640			continue;
641		} else if (status != DMA_COMPLETE) {
642			dmaengine_unmap_put(um);
643			result(status == DMA_ERROR ?
644			       "completion error status" :
645			       "completion busy status", total_tests, src_off,
646			       dst_off, len, ret);
647			failed_tests++;
648			continue;
649		}
650
651		dmaengine_unmap_put(um);
652
653		if (params->noverify) {
654			verbose_result("test passed", total_tests, src_off,
655				       dst_off, len, 0);
656			continue;
657		}
658
659		pr_debug("%s: verifying source buffer...\n", current->comm);
660		error_count = dmatest_verify(thread->srcs, 0, src_off,
661				0, PATTERN_SRC, true);
662		error_count += dmatest_verify(thread->srcs, src_off,
663				src_off + len, src_off,
664				PATTERN_SRC | PATTERN_COPY, true);
665		error_count += dmatest_verify(thread->srcs, src_off + len,
666				params->buf_size, src_off + len,
667				PATTERN_SRC, true);
668
669		pr_debug("%s: verifying dest buffer...\n", current->comm);
670		error_count += dmatest_verify(thread->dsts, 0, dst_off,
671				0, PATTERN_DST, false);
672		error_count += dmatest_verify(thread->dsts, dst_off,
673				dst_off + len, src_off,
674				PATTERN_SRC | PATTERN_COPY, false);
675		error_count += dmatest_verify(thread->dsts, dst_off + len,
676				params->buf_size, dst_off + len,
677				PATTERN_DST, false);
678
679		if (error_count) {
680			result("data error", total_tests, src_off, dst_off,
681			       len, error_count);
682			failed_tests++;
683		} else {
684			verbose_result("test passed", total_tests, src_off,
685				       dst_off, len, 0);
686		}
687	}
688	runtime = ktime_us_delta(ktime_get(), ktime);
689
690	ret = 0;
691	for (i = 0; thread->dsts[i]; i++)
692		kfree(thread->dsts[i]);
693err_dstbuf:
694	kfree(thread->dsts);
695err_dsts:
696	for (i = 0; thread->srcs[i]; i++)
697		kfree(thread->srcs[i]);
698err_srcbuf:
699	kfree(thread->srcs);
700err_srcs:
701	kfree(pq_coefs);
702err_thread_type:
703	pr_info("%s: summary %u tests, %u failures %llu iops %llu KB/s (%d)\n",
704		current->comm, total_tests, failed_tests,
705		dmatest_persec(runtime, total_tests),
706		dmatest_KBs(runtime, total_len), ret);
707
708	/* terminate all transfers on specified channels */
709	if (ret)
710		dmaengine_terminate_all(chan);
711
712	thread->done = true;
713	wake_up(&thread_wait);
714
715	return ret;
716}
717
718static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
719{
720	struct dmatest_thread	*thread;
721	struct dmatest_thread	*_thread;
722	int			ret;
723
724	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
725		ret = kthread_stop(thread->task);
726		pr_debug("thread %s exited with status %d\n",
727			 thread->task->comm, ret);
728		list_del(&thread->node);
729		put_task_struct(thread->task);
730		kfree(thread);
731	}
732
733	/* terminate all transfers on specified channels */
734	dmaengine_terminate_all(dtc->chan);
735
736	kfree(dtc);
737}
738
739static int dmatest_add_threads(struct dmatest_info *info,
740		struct dmatest_chan *dtc, enum dma_transaction_type type)
741{
742	struct dmatest_params *params = &info->params;
743	struct dmatest_thread *thread;
744	struct dma_chan *chan = dtc->chan;
745	char *op;
746	unsigned int i;
747
748	if (type == DMA_MEMCPY)
749		op = "copy";
750	else if (type == DMA_XOR)
751		op = "xor";
752	else if (type == DMA_PQ)
753		op = "pq";
754	else
755		return -EINVAL;
756
757	for (i = 0; i < params->threads_per_chan; i++) {
758		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
759		if (!thread) {
760			pr_warn("No memory for %s-%s%u\n",
761				dma_chan_name(chan), op, i);
762			break;
763		}
764		thread->info = info;
765		thread->chan = dtc->chan;
766		thread->type = type;
767		smp_wmb();
768		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
769				dma_chan_name(chan), op, i);
770		if (IS_ERR(thread->task)) {
771			pr_warn("Failed to create thread %s-%s%u\n",
772				dma_chan_name(chan), op, i);
773			kfree(thread);
774			break;
775		}
776
777		/* srcbuf and dstbuf are allocated by the thread itself */
778		get_task_struct(thread->task);
779		list_add_tail(&thread->node, &dtc->threads);
780		wake_up_process(thread->task);
781	}
782
783	return i;
784}
785
786static int dmatest_add_channel(struct dmatest_info *info,
787		struct dma_chan *chan)
788{
789	struct dmatest_chan	*dtc;
790	struct dma_device	*dma_dev = chan->device;
791	unsigned int		thread_count = 0;
792	int cnt;
793
794	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
795	if (!dtc) {
796		pr_warn("No memory for %s\n", dma_chan_name(chan));
797		return -ENOMEM;
798	}
799
800	dtc->chan = chan;
801	INIT_LIST_HEAD(&dtc->threads);
802
803	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
804		cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
805		thread_count += cnt > 0 ? cnt : 0;
806	}
807	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
808		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
809		thread_count += cnt > 0 ? cnt : 0;
810	}
811	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
812		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
813		thread_count += cnt > 0 ? cnt : 0;
814	}
815
816	pr_info("Started %u threads using %s\n",
817		thread_count, dma_chan_name(chan));
818
819	list_add_tail(&dtc->node, &info->channels);
820	info->nr_channels++;
821
822	return 0;
823}
824
825static bool filter(struct dma_chan *chan, void *param)
826{
827	struct dmatest_params *params = param;
828
829	if (!dmatest_match_channel(params, chan) ||
830	    !dmatest_match_device(params, chan->device))
831		return false;
832	else
833		return true;
834}
835
836static void request_channels(struct dmatest_info *info,
837			     enum dma_transaction_type type)
838{
839	dma_cap_mask_t mask;
840
841	dma_cap_zero(mask);
842	dma_cap_set(type, mask);
843	for (;;) {
844		struct dmatest_params *params = &info->params;
845		struct dma_chan *chan;
846
847		chan = dma_request_channel(mask, filter, params);
848		if (chan) {
849			if (dmatest_add_channel(info, chan)) {
850				dma_release_channel(chan);
851				break; /* add_channel failed, punt */
852			}
853		} else
854			break; /* no more channels available */
855		if (params->max_channels &&
856		    info->nr_channels >= params->max_channels)
857			break; /* we have all we need */
858	}
859}
860
861static void run_threaded_test(struct dmatest_info *info)
862{
863	struct dmatest_params *params = &info->params;
864
865	/* Copy test parameters */
866	params->buf_size = test_buf_size;
867	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
868	strlcpy(params->device, strim(test_device), sizeof(params->device));
869	params->threads_per_chan = threads_per_chan;
870	params->max_channels = max_channels;
871	params->iterations = iterations;
872	params->xor_sources = xor_sources;
873	params->pq_sources = pq_sources;
874	params->timeout = timeout;
875	params->noverify = noverify;
876
877	request_channels(info, DMA_MEMCPY);
878	request_channels(info, DMA_XOR);
879	request_channels(info, DMA_PQ);
880}
881
882static void stop_threaded_test(struct dmatest_info *info)
883{
884	struct dmatest_chan *dtc, *_dtc;
885	struct dma_chan *chan;
886
887	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
888		list_del(&dtc->node);
889		chan = dtc->chan;
890		dmatest_cleanup_channel(dtc);
891		pr_debug("dropped channel %s\n", dma_chan_name(chan));
892		dma_release_channel(chan);
893	}
894
895	info->nr_channels = 0;
896}
897
898static void restart_threaded_test(struct dmatest_info *info, bool run)
899{
900	/* we might be called early to set run=, defer running until all
901	 * parameters have been evaluated
902	 */
903	if (!info->did_init)
904		return;
905
906	/* Stop any running test first */
907	stop_threaded_test(info);
908
909	/* Run test with new parameters */
910	run_threaded_test(info);
911}
912
913static int dmatest_run_get(char *val, const struct kernel_param *kp)
914{
915	struct dmatest_info *info = &test_info;
916
917	mutex_lock(&info->lock);
918	if (is_threaded_test_run(info)) {
919		dmatest_run = true;
920	} else {
921		stop_threaded_test(info);
922		dmatest_run = false;
923	}
924	mutex_unlock(&info->lock);
925
926	return param_get_bool(val, kp);
927}
928
929static int dmatest_run_set(const char *val, const struct kernel_param *kp)
930{
931	struct dmatest_info *info = &test_info;
932	int ret;
933
934	mutex_lock(&info->lock);
935	ret = param_set_bool(val, kp);
936	if (ret) {
937		mutex_unlock(&info->lock);
938		return ret;
939	}
940
941	if (is_threaded_test_run(info))
942		ret = -EBUSY;
943	else if (dmatest_run)
944		restart_threaded_test(info, dmatest_run);
945
946	mutex_unlock(&info->lock);
947
948	return ret;
949}
950
951static int __init dmatest_init(void)
952{
953	struct dmatest_info *info = &test_info;
954	struct dmatest_params *params = &info->params;
955
956	if (dmatest_run) {
957		mutex_lock(&info->lock);
958		run_threaded_test(info);
959		mutex_unlock(&info->lock);
960	}
961
962	if (params->iterations && wait)
963		wait_event(thread_wait, !is_threaded_test_run(info));
964
965	/* module parameters are stable, inittime tests are started,
966	 * let userspace take over 'run' control
967	 */
968	info->did_init = true;
969
970	return 0;
971}
972/* when compiled-in wait for drivers to load first */
973late_initcall(dmatest_init);
974
975static void __exit dmatest_exit(void)
976{
977	struct dmatest_info *info = &test_info;
978
979	mutex_lock(&info->lock);
980	stop_threaded_test(info);
981	mutex_unlock(&info->lock);
982}
983module_exit(dmatest_exit);
984
985MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
986MODULE_LICENSE("GPL v2");
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * DMA Engine test module
   4 *
   5 * Copyright (C) 2007 Atmel Corporation
   6 * Copyright (C) 2013 Intel Corporation
   7 */
   8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10#include <linux/delay.h>
  11#include <linux/dma-mapping.h>
  12#include <linux/dmaengine.h>
  13#include <linux/freezer.h>
  14#include <linux/init.h>
  15#include <linux/kthread.h>
  16#include <linux/sched/task.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
  23static unsigned int test_buf_size = 16384;
  24module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
  25MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
  26
  27static char test_device[32];
  28module_param_string(device, test_device, sizeof(test_device),
  29		S_IRUGO | S_IWUSR);
  30MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
  31
  32static unsigned int threads_per_chan = 1;
  33module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
  34MODULE_PARM_DESC(threads_per_chan,
  35		"Number of threads to start per channel (default: 1)");
  36
  37static unsigned int max_channels;
  38module_param(max_channels, uint, S_IRUGO | S_IWUSR);
  39MODULE_PARM_DESC(max_channels,
  40		"Maximum number of channels to use (default: all)");
  41
  42static unsigned int iterations;
  43module_param(iterations, uint, S_IRUGO | S_IWUSR);
  44MODULE_PARM_DESC(iterations,
  45		"Iterations before stopping test (default: infinite)");
  46
  47static unsigned int dmatest;
  48module_param(dmatest, uint, S_IRUGO | S_IWUSR);
  49MODULE_PARM_DESC(dmatest,
  50		"dmatest 0-memcpy 1-memset (default: 0)");
  51
  52static unsigned int xor_sources = 3;
  53module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
  54MODULE_PARM_DESC(xor_sources,
  55		"Number of xor source buffers (default: 3)");
  56
  57static unsigned int pq_sources = 3;
  58module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
  59MODULE_PARM_DESC(pq_sources,
  60		"Number of p+q source buffers (default: 3)");
  61
  62static int timeout = 3000;
  63module_param(timeout, int, S_IRUGO | S_IWUSR);
  64MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
  65		 "Pass -1 for infinite timeout");
  66
  67static bool noverify;
  68module_param(noverify, bool, S_IRUGO | S_IWUSR);
  69MODULE_PARM_DESC(noverify, "Disable data verification (default: verify)");
  70
  71static bool norandom;
  72module_param(norandom, bool, 0644);
  73MODULE_PARM_DESC(norandom, "Disable random offset setup (default: random)");
  74
  75static bool verbose;
  76module_param(verbose, bool, S_IRUGO | S_IWUSR);
  77MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
  78
  79static int alignment = -1;
  80module_param(alignment, int, 0644);
  81MODULE_PARM_DESC(alignment, "Custom data address alignment taken as 2^(alignment) (default: not used (-1))");
  82
  83static unsigned int transfer_size;
  84module_param(transfer_size, uint, 0644);
  85MODULE_PARM_DESC(transfer_size, "Optional custom transfer size in bytes (default: not used (0))");
  86
  87static bool polled;
  88module_param(polled, bool, S_IRUGO | S_IWUSR);
  89MODULE_PARM_DESC(polled, "Use polling for completion instead of interrupts");
  90
  91/**
  92 * struct dmatest_params - test parameters.
  93 * @buf_size:		size of the memcpy test buffer
  94 * @channel:		bus ID of the channel to test
  95 * @device:		bus ID of the DMA Engine to test
  96 * @threads_per_chan:	number of threads to start per channel
  97 * @max_channels:	maximum number of channels to use
  98 * @iterations:		iterations before stopping test
  99 * @xor_sources:	number of xor source buffers
 100 * @pq_sources:		number of p+q source buffers
 101 * @timeout:		transfer timeout in msec, -1 for infinite timeout
 102 * @noverify:		disable data verification
 103 * @norandom:		disable random offset setup
 104 * @alignment:		custom data address alignment taken as 2^alignment
 105 * @transfer_size:	custom transfer size in bytes
 106 * @polled:		use polling for completion instead of interrupts
 107 */
 108struct dmatest_params {
 109	unsigned int	buf_size;
 110	char		channel[20];
 111	char		device[32];
 112	unsigned int	threads_per_chan;
 113	unsigned int	max_channels;
 114	unsigned int	iterations;
 115	unsigned int	xor_sources;
 116	unsigned int	pq_sources;
 117	int		timeout;
 118	bool		noverify;
 119	bool		norandom;
 120	int		alignment;
 121	unsigned int	transfer_size;
 122	bool		polled;
 123};
 124
 125/**
 126 * struct dmatest_info - test information.
 127 * @params:		test parameters
 128 * @channels:		channels under test
 129 * @nr_channels:	number of channels under test
 130 * @lock:		access protection to the fields of this structure
 131 * @did_init:		module has been initialized completely
 132 * @last_error:		test has faced configuration issues
 133 */
 134static struct dmatest_info {
 135	/* Test parameters */
 136	struct dmatest_params	params;
 137
 138	/* Internal state */
 139	struct list_head	channels;
 140	unsigned int		nr_channels;
 141	int			last_error;
 142	struct mutex		lock;
 143	bool			did_init;
 144} test_info = {
 145	.channels = LIST_HEAD_INIT(test_info.channels),
 146	.lock = __MUTEX_INITIALIZER(test_info.lock),
 147};
 148
 149static int dmatest_run_set(const char *val, const struct kernel_param *kp);
 150static int dmatest_run_get(char *val, const struct kernel_param *kp);
 151static const struct kernel_param_ops run_ops = {
 152	.set = dmatest_run_set,
 153	.get = dmatest_run_get,
 154};
 155static bool dmatest_run;
 156module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
 157MODULE_PARM_DESC(run, "Run the test (default: false)");
 158
 159static int dmatest_chan_set(const char *val, const struct kernel_param *kp);
 160static int dmatest_chan_get(char *val, const struct kernel_param *kp);
 161static const struct kernel_param_ops multi_chan_ops = {
 162	.set = dmatest_chan_set,
 163	.get = dmatest_chan_get,
 164};
 165
 166static char test_channel[20];
 167static struct kparam_string newchan_kps = {
 168	.string = test_channel,
 169	.maxlen = 20,
 170};
 171module_param_cb(channel, &multi_chan_ops, &newchan_kps, 0644);
 172MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
 173
 174static int dmatest_test_list_get(char *val, const struct kernel_param *kp);
 175static const struct kernel_param_ops test_list_ops = {
 176	.get = dmatest_test_list_get,
 177};
 178module_param_cb(test_list, &test_list_ops, NULL, 0444);
 179MODULE_PARM_DESC(test_list, "Print current test list");
 180
 181/* Maximum amount of mismatched bytes in buffer to print */
 182#define MAX_ERROR_COUNT		32
 183
 184/*
 185 * Initialization patterns. All bytes in the source buffer has bit 7
 186 * set, all bytes in the destination buffer has bit 7 cleared.
 187 *
 188 * Bit 6 is set for all bytes which are to be copied by the DMA
 189 * engine. Bit 5 is set for all bytes which are to be overwritten by
 190 * the DMA engine.
 191 *
 192 * The remaining bits are the inverse of a counter which increments by
 193 * one for each byte address.
 194 */
 195#define PATTERN_SRC		0x80
 196#define PATTERN_DST		0x00
 197#define PATTERN_COPY		0x40
 198#define PATTERN_OVERWRITE	0x20
 199#define PATTERN_COUNT_MASK	0x1f
 200#define PATTERN_MEMSET_IDX	0x01
 201
 202/* Fixed point arithmetic ops */
 203#define FIXPT_SHIFT		8
 204#define FIXPNT_MASK		0xFF
 205#define FIXPT_TO_INT(a)	((a) >> FIXPT_SHIFT)
 206#define INT_TO_FIXPT(a)	((a) << FIXPT_SHIFT)
 207#define FIXPT_GET_FRAC(a)	((((a) & FIXPNT_MASK) * 100) >> FIXPT_SHIFT)
 208
 209/* poor man's completion - we want to use wait_event_freezable() on it */
 210struct dmatest_done {
 211	bool			done;
 212	wait_queue_head_t	*wait;
 213};
 214
 215struct dmatest_data {
 216	u8		**raw;
 217	u8		**aligned;
 218	unsigned int	cnt;
 219	unsigned int	off;
 220};
 221
 222struct dmatest_thread {
 223	struct list_head	node;
 224	struct dmatest_info	*info;
 225	struct task_struct	*task;
 226	struct dma_chan		*chan;
 227	struct dmatest_data	src;
 228	struct dmatest_data	dst;
 229	enum dma_transaction_type type;
 230	wait_queue_head_t done_wait;
 231	struct dmatest_done test_done;
 232	bool			done;
 233	bool			pending;
 234};
 235
 236struct dmatest_chan {
 237	struct list_head	node;
 238	struct dma_chan		*chan;
 239	struct list_head	threads;
 240};
 241
 242static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
 243static bool wait;
 244
 245static bool is_threaded_test_run(struct dmatest_info *info)
 246{
 247	struct dmatest_chan *dtc;
 248
 249	list_for_each_entry(dtc, &info->channels, node) {
 250		struct dmatest_thread *thread;
 251
 252		list_for_each_entry(thread, &dtc->threads, node) {
 253			if (!thread->done && !thread->pending)
 254				return true;
 255		}
 256	}
 257
 258	return false;
 259}
 260
 261static bool is_threaded_test_pending(struct dmatest_info *info)
 262{
 263	struct dmatest_chan *dtc;
 264
 265	list_for_each_entry(dtc, &info->channels, node) {
 266		struct dmatest_thread *thread;
 267
 268		list_for_each_entry(thread, &dtc->threads, node) {
 269			if (thread->pending)
 270				return true;
 271		}
 272	}
 273
 274	return false;
 275}
 276
 277static int dmatest_wait_get(char *val, const struct kernel_param *kp)
 278{
 279	struct dmatest_info *info = &test_info;
 280	struct dmatest_params *params = &info->params;
 281
 282	if (params->iterations)
 283		wait_event(thread_wait, !is_threaded_test_run(info));
 284	wait = true;
 285	return param_get_bool(val, kp);
 286}
 287
 288static const struct kernel_param_ops wait_ops = {
 289	.get = dmatest_wait_get,
 290	.set = param_set_bool,
 291};
 292module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
 293MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
 294
 295static bool dmatest_match_channel(struct dmatest_params *params,
 296		struct dma_chan *chan)
 297{
 298	if (params->channel[0] == '\0')
 299		return true;
 300	return strcmp(dma_chan_name(chan), params->channel) == 0;
 301}
 302
 303static bool dmatest_match_device(struct dmatest_params *params,
 304		struct dma_device *device)
 305{
 306	if (params->device[0] == '\0')
 307		return true;
 308	return strcmp(dev_name(device->dev), params->device) == 0;
 309}
 310
 311static unsigned long dmatest_random(void)
 312{
 313	unsigned long buf;
 314
 315	prandom_bytes(&buf, sizeof(buf));
 316	return buf;
 317}
 318
 319static inline u8 gen_inv_idx(u8 index, bool is_memset)
 320{
 321	u8 val = is_memset ? PATTERN_MEMSET_IDX : index;
 322
 323	return ~val & PATTERN_COUNT_MASK;
 324}
 325
 326static inline u8 gen_src_value(u8 index, bool is_memset)
 327{
 328	return PATTERN_SRC | gen_inv_idx(index, is_memset);
 329}
 330
 331static inline u8 gen_dst_value(u8 index, bool is_memset)
 332{
 333	return PATTERN_DST | gen_inv_idx(index, is_memset);
 334}
 335
 336static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
 337		unsigned int buf_size, bool is_memset)
 338{
 339	unsigned int i;
 340	u8 *buf;
 341
 342	for (; (buf = *bufs); bufs++) {
 343		for (i = 0; i < start; i++)
 344			buf[i] = gen_src_value(i, is_memset);
 345		for ( ; i < start + len; i++)
 346			buf[i] = gen_src_value(i, is_memset) | PATTERN_COPY;
 347		for ( ; i < buf_size; i++)
 348			buf[i] = gen_src_value(i, is_memset);
 349		buf++;
 350	}
 351}
 352
 353static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
 354		unsigned int buf_size, bool is_memset)
 355{
 356	unsigned int i;
 357	u8 *buf;
 358
 359	for (; (buf = *bufs); bufs++) {
 360		for (i = 0; i < start; i++)
 361			buf[i] = gen_dst_value(i, is_memset);
 362		for ( ; i < start + len; i++)
 363			buf[i] = gen_dst_value(i, is_memset) |
 364						PATTERN_OVERWRITE;
 365		for ( ; i < buf_size; i++)
 366			buf[i] = gen_dst_value(i, is_memset);
 367	}
 368}
 369
 370static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
 371		unsigned int counter, bool is_srcbuf, bool is_memset)
 372{
 373	u8		diff = actual ^ pattern;
 374	u8		expected = pattern | gen_inv_idx(counter, is_memset);
 375	const char	*thread_name = current->comm;
 376
 377	if (is_srcbuf)
 378		pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
 379			thread_name, index, expected, actual);
 380	else if ((pattern & PATTERN_COPY)
 381			&& (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
 382		pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
 383			thread_name, index, expected, actual);
 384	else if (diff & PATTERN_SRC)
 385		pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
 386			thread_name, index, expected, actual);
 387	else
 388		pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
 389			thread_name, index, expected, actual);
 390}
 391
 392static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
 393		unsigned int end, unsigned int counter, u8 pattern,
 394		bool is_srcbuf, bool is_memset)
 395{
 396	unsigned int i;
 397	unsigned int error_count = 0;
 398	u8 actual;
 399	u8 expected;
 400	u8 *buf;
 401	unsigned int counter_orig = counter;
 402
 403	for (; (buf = *bufs); bufs++) {
 404		counter = counter_orig;
 405		for (i = start; i < end; i++) {
 406			actual = buf[i];
 407			expected = pattern | gen_inv_idx(counter, is_memset);
 408			if (actual != expected) {
 409				if (error_count < MAX_ERROR_COUNT)
 410					dmatest_mismatch(actual, pattern, i,
 411							 counter, is_srcbuf,
 412							 is_memset);
 413				error_count++;
 414			}
 415			counter++;
 416		}
 417	}
 418
 419	if (error_count > MAX_ERROR_COUNT)
 420		pr_warn("%s: %u errors suppressed\n",
 421			current->comm, error_count - MAX_ERROR_COUNT);
 422
 423	return error_count;
 424}
 425
 426
 427static void dmatest_callback(void *arg)
 428{
 429	struct dmatest_done *done = arg;
 430	struct dmatest_thread *thread =
 431		container_of(done, struct dmatest_thread, test_done);
 432	if (!thread->done) {
 433		done->done = true;
 434		wake_up_all(done->wait);
 435	} else {
 436		/*
 437		 * If thread->done, it means that this callback occurred
 438		 * after the parent thread has cleaned up. This can
 439		 * happen in the case that driver doesn't implement
 440		 * the terminate_all() functionality and a dma operation
 441		 * did not occur within the timeout period
 442		 */
 443		WARN(1, "dmatest: Kernel memory may be corrupted!!\n");
 444	}
 445}
 446
 447static unsigned int min_odd(unsigned int x, unsigned int y)
 448{
 449	unsigned int val = min(x, y);
 450
 451	return val % 2 ? val : val - 1;
 452}
 453
 454static void result(const char *err, unsigned int n, unsigned int src_off,
 455		   unsigned int dst_off, unsigned int len, unsigned long data)
 456{
 457	pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 458		current->comm, n, err, src_off, dst_off, len, data);
 459}
 460
 461static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
 462		       unsigned int dst_off, unsigned int len,
 463		       unsigned long data)
 464{
 465	pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 466		 current->comm, n, err, src_off, dst_off, len, data);
 467}
 468
 469#define verbose_result(err, n, src_off, dst_off, len, data) ({	\
 470	if (verbose)						\
 471		result(err, n, src_off, dst_off, len, data);	\
 472	else							\
 473		dbg_result(err, n, src_off, dst_off, len, data);\
 474})
 475
 476static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
 477{
 478	unsigned long long per_sec = 1000000;
 479
 480	if (runtime <= 0)
 481		return 0;
 482
 483	/* drop precision until runtime is 32-bits */
 484	while (runtime > UINT_MAX) {
 485		runtime >>= 1;
 486		per_sec <<= 1;
 487	}
 488
 489	per_sec *= val;
 490	per_sec = INT_TO_FIXPT(per_sec);
 491	do_div(per_sec, runtime);
 492
 493	return per_sec;
 494}
 495
 496static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
 497{
 498	return FIXPT_TO_INT(dmatest_persec(runtime, len >> 10));
 499}
 500
 501static void __dmatest_free_test_data(struct dmatest_data *d, unsigned int cnt)
 502{
 503	unsigned int i;
 504
 505	for (i = 0; i < cnt; i++)
 506		kfree(d->raw[i]);
 507
 508	kfree(d->aligned);
 509	kfree(d->raw);
 510}
 511
 512static void dmatest_free_test_data(struct dmatest_data *d)
 513{
 514	__dmatest_free_test_data(d, d->cnt);
 515}
 516
 517static int dmatest_alloc_test_data(struct dmatest_data *d,
 518		unsigned int buf_size, u8 align)
 519{
 520	unsigned int i = 0;
 521
 522	d->raw = kcalloc(d->cnt + 1, sizeof(u8 *), GFP_KERNEL);
 523	if (!d->raw)
 524		return -ENOMEM;
 525
 526	d->aligned = kcalloc(d->cnt + 1, sizeof(u8 *), GFP_KERNEL);
 527	if (!d->aligned)
 528		goto err;
 529
 530	for (i = 0; i < d->cnt; i++) {
 531		d->raw[i] = kmalloc(buf_size + align, GFP_KERNEL);
 532		if (!d->raw[i])
 533			goto err;
 534
 535		/* align to alignment restriction */
 536		if (align)
 537			d->aligned[i] = PTR_ALIGN(d->raw[i], align);
 538		else
 539			d->aligned[i] = d->raw[i];
 540	}
 541
 542	return 0;
 543err:
 544	__dmatest_free_test_data(d, i);
 545	return -ENOMEM;
 546}
 547
 548/*
 549 * This function repeatedly tests DMA transfers of various lengths and
 550 * offsets for a given operation type until it is told to exit by
 551 * kthread_stop(). There may be multiple threads running this function
 552 * in parallel for a single channel, and there may be multiple channels
 553 * being tested in parallel.
 554 *
 555 * Before each test, the source and destination buffer is initialized
 556 * with a known pattern. This pattern is different depending on
 557 * whether it's in an area which is supposed to be copied or
 558 * overwritten, and different in the source and destination buffers.
 559 * So if the DMA engine doesn't copy exactly what we tell it to copy,
 560 * we'll notice.
 561 */
 562static int dmatest_func(void *data)
 563{
 564	struct dmatest_thread	*thread = data;
 565	struct dmatest_done	*done = &thread->test_done;
 566	struct dmatest_info	*info;
 567	struct dmatest_params	*params;
 568	struct dma_chan		*chan;
 569	struct dma_device	*dev;
 570	unsigned int		error_count;
 571	unsigned int		failed_tests = 0;
 572	unsigned int		total_tests = 0;
 573	dma_cookie_t		cookie;
 574	enum dma_status		status;
 575	enum dma_ctrl_flags 	flags;
 576	u8			*pq_coefs = NULL;
 577	int			ret;
 578	unsigned int 		buf_size;
 579	struct dmatest_data	*src;
 580	struct dmatest_data	*dst;
 581	int			i;
 582	ktime_t			ktime, start, diff;
 583	ktime_t			filltime = 0;
 584	ktime_t			comparetime = 0;
 585	s64			runtime = 0;
 586	unsigned long long	total_len = 0;
 587	unsigned long long	iops = 0;
 588	u8			align = 0;
 589	bool			is_memset = false;
 590	dma_addr_t		*srcs;
 591	dma_addr_t		*dma_pq;
 592
 593	set_freezable();
 594
 595	ret = -ENOMEM;
 596
 597	smp_rmb();
 598	thread->pending = false;
 599	info = thread->info;
 600	params = &info->params;
 601	chan = thread->chan;
 602	dev = chan->device;
 603	src = &thread->src;
 604	dst = &thread->dst;
 605	if (thread->type == DMA_MEMCPY) {
 606		align = params->alignment < 0 ? dev->copy_align :
 607						params->alignment;
 608		src->cnt = dst->cnt = 1;
 609	} else if (thread->type == DMA_MEMSET) {
 610		align = params->alignment < 0 ? dev->fill_align :
 611						params->alignment;
 612		src->cnt = dst->cnt = 1;
 613		is_memset = true;
 614	} else if (thread->type == DMA_XOR) {
 615		/* force odd to ensure dst = src */
 616		src->cnt = min_odd(params->xor_sources | 1, dev->max_xor);
 617		dst->cnt = 1;
 618		align = params->alignment < 0 ? dev->xor_align :
 619						params->alignment;
 620	} else if (thread->type == DMA_PQ) {
 621		/* force odd to ensure dst = src */
 622		src->cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
 623		dst->cnt = 2;
 624		align = params->alignment < 0 ? dev->pq_align :
 625						params->alignment;
 626
 627		pq_coefs = kmalloc(params->pq_sources + 1, GFP_KERNEL);
 628		if (!pq_coefs)
 629			goto err_thread_type;
 630
 631		for (i = 0; i < src->cnt; i++)
 632			pq_coefs[i] = 1;
 633	} else
 634		goto err_thread_type;
 635
 636	/* Check if buffer count fits into map count variable (u8) */
 637	if ((src->cnt + dst->cnt) >= 255) {
 638		pr_err("too many buffers (%d of 255 supported)\n",
 639		       src->cnt + dst->cnt);
 640		goto err_free_coefs;
 641	}
 642
 643	buf_size = params->buf_size;
 644	if (1 << align > buf_size) {
 645		pr_err("%u-byte buffer too small for %d-byte alignment\n",
 646		       buf_size, 1 << align);
 647		goto err_free_coefs;
 648	}
 649
 650	if (dmatest_alloc_test_data(src, buf_size, align) < 0)
 651		goto err_free_coefs;
 652
 653	if (dmatest_alloc_test_data(dst, buf_size, align) < 0)
 654		goto err_src;
 655
 656	set_user_nice(current, 10);
 657
 658	srcs = kcalloc(src->cnt, sizeof(dma_addr_t), GFP_KERNEL);
 659	if (!srcs)
 660		goto err_dst;
 661
 662	dma_pq = kcalloc(dst->cnt, sizeof(dma_addr_t), GFP_KERNEL);
 663	if (!dma_pq)
 664		goto err_srcs_array;
 665
 666	/*
 667	 * src and dst buffers are freed by ourselves below
 668	 */
 669	if (params->polled)
 670		flags = DMA_CTRL_ACK;
 671	else
 672		flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
 673
 674	ktime = ktime_get();
 675	while (!(kthread_should_stop() ||
 676	       (params->iterations && total_tests >= params->iterations))) {
 677		struct dma_async_tx_descriptor *tx = NULL;
 678		struct dmaengine_unmap_data *um;
 679		dma_addr_t *dsts;
 680		unsigned int len;
 681
 682		total_tests++;
 683
 684		if (params->transfer_size) {
 685			if (params->transfer_size >= buf_size) {
 686				pr_err("%u-byte transfer size must be lower than %u-buffer size\n",
 687				       params->transfer_size, buf_size);
 688				break;
 689			}
 690			len = params->transfer_size;
 691		} else if (params->norandom) {
 692			len = buf_size;
 693		} else {
 694			len = dmatest_random() % buf_size + 1;
 695		}
 696
 697		/* Do not alter transfer size explicitly defined by user */
 698		if (!params->transfer_size) {
 699			len = (len >> align) << align;
 700			if (!len)
 701				len = 1 << align;
 702		}
 703		total_len += len;
 704
 705		if (params->norandom) {
 706			src->off = 0;
 707			dst->off = 0;
 708		} else {
 709			src->off = dmatest_random() % (buf_size - len + 1);
 710			dst->off = dmatest_random() % (buf_size - len + 1);
 711
 712			src->off = (src->off >> align) << align;
 713			dst->off = (dst->off >> align) << align;
 714		}
 715
 716		if (!params->noverify) {
 717			start = ktime_get();
 718			dmatest_init_srcs(src->aligned, src->off, len,
 719					  buf_size, is_memset);
 720			dmatest_init_dsts(dst->aligned, dst->off, len,
 721					  buf_size, is_memset);
 722
 723			diff = ktime_sub(ktime_get(), start);
 724			filltime = ktime_add(filltime, diff);
 725		}
 726
 727		um = dmaengine_get_unmap_data(dev->dev, src->cnt + dst->cnt,
 728					      GFP_KERNEL);
 729		if (!um) {
 730			failed_tests++;
 731			result("unmap data NULL", total_tests,
 732			       src->off, dst->off, len, ret);
 733			continue;
 734		}
 735
 736		um->len = buf_size;
 737		for (i = 0; i < src->cnt; i++) {
 738			void *buf = src->aligned[i];
 739			struct page *pg = virt_to_page(buf);
 740			unsigned long pg_off = offset_in_page(buf);
 741
 742			um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
 743						   um->len, DMA_TO_DEVICE);
 744			srcs[i] = um->addr[i] + src->off;
 745			ret = dma_mapping_error(dev->dev, um->addr[i]);
 746			if (ret) {
 747				result("src mapping error", total_tests,
 748				       src->off, dst->off, len, ret);
 749				goto error_unmap_continue;
 750			}
 751			um->to_cnt++;
 752		}
 753		/* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
 754		dsts = &um->addr[src->cnt];
 755		for (i = 0; i < dst->cnt; i++) {
 756			void *buf = dst->aligned[i];
 757			struct page *pg = virt_to_page(buf);
 758			unsigned long pg_off = offset_in_page(buf);
 759
 760			dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
 761					       DMA_BIDIRECTIONAL);
 762			ret = dma_mapping_error(dev->dev, dsts[i]);
 763			if (ret) {
 764				result("dst mapping error", total_tests,
 765				       src->off, dst->off, len, ret);
 766				goto error_unmap_continue;
 767			}
 768			um->bidi_cnt++;
 769		}
 770
 771		if (thread->type == DMA_MEMCPY)
 772			tx = dev->device_prep_dma_memcpy(chan,
 773							 dsts[0] + dst->off,
 774							 srcs[0], len, flags);
 775		else if (thread->type == DMA_MEMSET)
 776			tx = dev->device_prep_dma_memset(chan,
 777						dsts[0] + dst->off,
 778						*(src->aligned[0] + src->off),
 779						len, flags);
 780		else if (thread->type == DMA_XOR)
 781			tx = dev->device_prep_dma_xor(chan,
 782						      dsts[0] + dst->off,
 783						      srcs, src->cnt,
 784						      len, flags);
 785		else if (thread->type == DMA_PQ) {
 786			for (i = 0; i < dst->cnt; i++)
 787				dma_pq[i] = dsts[i] + dst->off;
 788			tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
 789						     src->cnt, pq_coefs,
 790						     len, flags);
 791		}
 792
 793		if (!tx) {
 794			result("prep error", total_tests, src->off,
 795			       dst->off, len, ret);
 796			msleep(100);
 797			goto error_unmap_continue;
 798		}
 799
 800		done->done = false;
 801		if (!params->polled) {
 802			tx->callback = dmatest_callback;
 803			tx->callback_param = done;
 804		}
 805		cookie = tx->tx_submit(tx);
 806
 807		if (dma_submit_error(cookie)) {
 808			result("submit error", total_tests, src->off,
 809			       dst->off, len, ret);
 810			msleep(100);
 811			goto error_unmap_continue;
 812		}
 813
 814		if (params->polled) {
 815			status = dma_sync_wait(chan, cookie);
 816			dmaengine_terminate_sync(chan);
 817			if (status == DMA_COMPLETE)
 818				done->done = true;
 819		} else {
 820			dma_async_issue_pending(chan);
 821
 822			wait_event_freezable_timeout(thread->done_wait,
 823					done->done,
 824					msecs_to_jiffies(params->timeout));
 825
 826			status = dma_async_is_tx_complete(chan, cookie, NULL,
 827							  NULL);
 828		}
 829
 830		if (!done->done) {
 831			result("test timed out", total_tests, src->off, dst->off,
 832			       len, 0);
 833			goto error_unmap_continue;
 834		} else if (status != DMA_COMPLETE &&
 835			   !(dma_has_cap(DMA_COMPLETION_NO_ORDER,
 836					 dev->cap_mask) &&
 837			     status == DMA_OUT_OF_ORDER)) {
 838			result(status == DMA_ERROR ?
 839			       "completion error status" :
 840			       "completion busy status", total_tests, src->off,
 841			       dst->off, len, ret);
 842			goto error_unmap_continue;
 843		}
 844
 845		dmaengine_unmap_put(um);
 846
 847		if (params->noverify) {
 848			verbose_result("test passed", total_tests, src->off,
 849				       dst->off, len, 0);
 850			continue;
 851		}
 852
 853		start = ktime_get();
 854		pr_debug("%s: verifying source buffer...\n", current->comm);
 855		error_count = dmatest_verify(src->aligned, 0, src->off,
 856				0, PATTERN_SRC, true, is_memset);
 857		error_count += dmatest_verify(src->aligned, src->off,
 858				src->off + len, src->off,
 859				PATTERN_SRC | PATTERN_COPY, true, is_memset);
 860		error_count += dmatest_verify(src->aligned, src->off + len,
 861				buf_size, src->off + len,
 862				PATTERN_SRC, true, is_memset);
 863
 864		pr_debug("%s: verifying dest buffer...\n", current->comm);
 865		error_count += dmatest_verify(dst->aligned, 0, dst->off,
 866				0, PATTERN_DST, false, is_memset);
 867
 868		error_count += dmatest_verify(dst->aligned, dst->off,
 869				dst->off + len, src->off,
 870				PATTERN_SRC | PATTERN_COPY, false, is_memset);
 871
 872		error_count += dmatest_verify(dst->aligned, dst->off + len,
 873				buf_size, dst->off + len,
 874				PATTERN_DST, false, is_memset);
 875
 876		diff = ktime_sub(ktime_get(), start);
 877		comparetime = ktime_add(comparetime, diff);
 878
 879		if (error_count) {
 880			result("data error", total_tests, src->off, dst->off,
 881			       len, error_count);
 882			failed_tests++;
 883		} else {
 884			verbose_result("test passed", total_tests, src->off,
 885				       dst->off, len, 0);
 886		}
 887
 888		continue;
 889
 890error_unmap_continue:
 891		dmaengine_unmap_put(um);
 892		failed_tests++;
 893	}
 894	ktime = ktime_sub(ktime_get(), ktime);
 895	ktime = ktime_sub(ktime, comparetime);
 896	ktime = ktime_sub(ktime, filltime);
 897	runtime = ktime_to_us(ktime);
 898
 899	ret = 0;
 900	kfree(dma_pq);
 901err_srcs_array:
 902	kfree(srcs);
 903err_dst:
 904	dmatest_free_test_data(dst);
 905err_src:
 906	dmatest_free_test_data(src);
 907err_free_coefs:
 908	kfree(pq_coefs);
 909err_thread_type:
 910	iops = dmatest_persec(runtime, total_tests);
 911	pr_info("%s: summary %u tests, %u failures %llu.%02llu iops %llu KB/s (%d)\n",
 912		current->comm, total_tests, failed_tests,
 913		FIXPT_TO_INT(iops), FIXPT_GET_FRAC(iops),
 914		dmatest_KBs(runtime, total_len), ret);
 915
 916	/* terminate all transfers on specified channels */
 917	if (ret || failed_tests)
 918		dmaengine_terminate_sync(chan);
 919
 920	thread->done = true;
 921	wake_up(&thread_wait);
 922
 923	return ret;
 924}
 925
 926static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
 927{
 928	struct dmatest_thread	*thread;
 929	struct dmatest_thread	*_thread;
 930	int			ret;
 931
 932	list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
 933		ret = kthread_stop(thread->task);
 934		pr_debug("thread %s exited with status %d\n",
 935			 thread->task->comm, ret);
 936		list_del(&thread->node);
 937		put_task_struct(thread->task);
 938		kfree(thread);
 939	}
 940
 941	/* terminate all transfers on specified channels */
 942	dmaengine_terminate_sync(dtc->chan);
 943
 944	kfree(dtc);
 945}
 946
 947static int dmatest_add_threads(struct dmatest_info *info,
 948		struct dmatest_chan *dtc, enum dma_transaction_type type)
 949{
 950	struct dmatest_params *params = &info->params;
 951	struct dmatest_thread *thread;
 952	struct dma_chan *chan = dtc->chan;
 953	char *op;
 954	unsigned int i;
 955
 956	if (type == DMA_MEMCPY)
 957		op = "copy";
 958	else if (type == DMA_MEMSET)
 959		op = "set";
 960	else if (type == DMA_XOR)
 961		op = "xor";
 962	else if (type == DMA_PQ)
 963		op = "pq";
 964	else
 965		return -EINVAL;
 966
 967	for (i = 0; i < params->threads_per_chan; i++) {
 968		thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
 969		if (!thread) {
 970			pr_warn("No memory for %s-%s%u\n",
 971				dma_chan_name(chan), op, i);
 972			break;
 973		}
 974		thread->info = info;
 975		thread->chan = dtc->chan;
 976		thread->type = type;
 977		thread->test_done.wait = &thread->done_wait;
 978		init_waitqueue_head(&thread->done_wait);
 979		smp_wmb();
 980		thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
 981				dma_chan_name(chan), op, i);
 982		if (IS_ERR(thread->task)) {
 983			pr_warn("Failed to create thread %s-%s%u\n",
 984				dma_chan_name(chan), op, i);
 985			kfree(thread);
 986			break;
 987		}
 988
 989		/* srcbuf and dstbuf are allocated by the thread itself */
 990		get_task_struct(thread->task);
 991		list_add_tail(&thread->node, &dtc->threads);
 992		thread->pending = true;
 993	}
 994
 995	return i;
 996}
 997
 998static int dmatest_add_channel(struct dmatest_info *info,
 999		struct dma_chan *chan)
1000{
1001	struct dmatest_chan	*dtc;
1002	struct dma_device	*dma_dev = chan->device;
1003	unsigned int		thread_count = 0;
1004	int cnt;
1005
1006	dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
1007	if (!dtc) {
1008		pr_warn("No memory for %s\n", dma_chan_name(chan));
1009		return -ENOMEM;
1010	}
1011
1012	dtc->chan = chan;
1013	INIT_LIST_HEAD(&dtc->threads);
1014
1015	if (dma_has_cap(DMA_COMPLETION_NO_ORDER, dma_dev->cap_mask) &&
1016	    info->params.polled) {
1017		info->params.polled = false;
1018		pr_warn("DMA_COMPLETION_NO_ORDER, polled disabled\n");
1019	}
1020
1021	if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
1022		if (dmatest == 0) {
1023			cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
1024			thread_count += cnt > 0 ? cnt : 0;
1025		}
1026	}
1027
1028	if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
1029		if (dmatest == 1) {
1030			cnt = dmatest_add_threads(info, dtc, DMA_MEMSET);
1031			thread_count += cnt > 0 ? cnt : 0;
1032		}
1033	}
1034
1035	if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1036		cnt = dmatest_add_threads(info, dtc, DMA_XOR);
1037		thread_count += cnt > 0 ? cnt : 0;
1038	}
1039	if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1040		cnt = dmatest_add_threads(info, dtc, DMA_PQ);
1041		thread_count += cnt > 0 ? cnt : 0;
1042	}
1043
1044	pr_info("Added %u threads using %s\n",
1045		thread_count, dma_chan_name(chan));
1046
1047	list_add_tail(&dtc->node, &info->channels);
1048	info->nr_channels++;
1049
1050	return 0;
1051}
1052
1053static bool filter(struct dma_chan *chan, void *param)
1054{
1055	struct dmatest_params *params = param;
1056
1057	if (!dmatest_match_channel(params, chan) ||
1058	    !dmatest_match_device(params, chan->device))
1059		return false;
1060	else
1061		return true;
1062}
1063
1064static void request_channels(struct dmatest_info *info,
1065			     enum dma_transaction_type type)
1066{
1067	dma_cap_mask_t mask;
1068
1069	dma_cap_zero(mask);
1070	dma_cap_set(type, mask);
1071	for (;;) {
1072		struct dmatest_params *params = &info->params;
1073		struct dma_chan *chan;
1074
1075		chan = dma_request_channel(mask, filter, params);
1076		if (chan) {
1077			if (dmatest_add_channel(info, chan)) {
1078				dma_release_channel(chan);
1079				break; /* add_channel failed, punt */
1080			}
1081		} else
1082			break; /* no more channels available */
1083		if (params->max_channels &&
1084		    info->nr_channels >= params->max_channels)
1085			break; /* we have all we need */
1086	}
1087}
1088
1089static void add_threaded_test(struct dmatest_info *info)
1090{
1091	struct dmatest_params *params = &info->params;
1092
1093	/* Copy test parameters */
1094	params->buf_size = test_buf_size;
1095	strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
1096	strlcpy(params->device, strim(test_device), sizeof(params->device));
1097	params->threads_per_chan = threads_per_chan;
1098	params->max_channels = max_channels;
1099	params->iterations = iterations;
1100	params->xor_sources = xor_sources;
1101	params->pq_sources = pq_sources;
1102	params->timeout = timeout;
1103	params->noverify = noverify;
1104	params->norandom = norandom;
1105	params->alignment = alignment;
1106	params->transfer_size = transfer_size;
1107	params->polled = polled;
1108
1109	request_channels(info, DMA_MEMCPY);
1110	request_channels(info, DMA_MEMSET);
1111	request_channels(info, DMA_XOR);
1112	request_channels(info, DMA_PQ);
1113}
1114
1115static void run_pending_tests(struct dmatest_info *info)
1116{
1117	struct dmatest_chan *dtc;
1118	unsigned int thread_count = 0;
1119
1120	list_for_each_entry(dtc, &info->channels, node) {
1121		struct dmatest_thread *thread;
1122
1123		thread_count = 0;
1124		list_for_each_entry(thread, &dtc->threads, node) {
1125			wake_up_process(thread->task);
1126			thread_count++;
1127		}
1128		pr_info("Started %u threads using %s\n",
1129			thread_count, dma_chan_name(dtc->chan));
1130	}
1131}
1132
1133static void stop_threaded_test(struct dmatest_info *info)
1134{
1135	struct dmatest_chan *dtc, *_dtc;
1136	struct dma_chan *chan;
1137
1138	list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
1139		list_del(&dtc->node);
1140		chan = dtc->chan;
1141		dmatest_cleanup_channel(dtc);
1142		pr_debug("dropped channel %s\n", dma_chan_name(chan));
1143		dma_release_channel(chan);
1144	}
1145
1146	info->nr_channels = 0;
1147}
1148
1149static void start_threaded_tests(struct dmatest_info *info)
1150{
1151	/* we might be called early to set run=, defer running until all
1152	 * parameters have been evaluated
1153	 */
1154	if (!info->did_init)
1155		return;
1156
1157	run_pending_tests(info);
1158}
1159
1160static int dmatest_run_get(char *val, const struct kernel_param *kp)
1161{
1162	struct dmatest_info *info = &test_info;
1163
1164	mutex_lock(&info->lock);
1165	if (is_threaded_test_run(info)) {
1166		dmatest_run = true;
1167	} else {
1168		if (!is_threaded_test_pending(info))
1169			stop_threaded_test(info);
1170		dmatest_run = false;
1171	}
1172	mutex_unlock(&info->lock);
1173
1174	return param_get_bool(val, kp);
1175}
1176
1177static int dmatest_run_set(const char *val, const struct kernel_param *kp)
1178{
1179	struct dmatest_info *info = &test_info;
1180	int ret;
1181
1182	mutex_lock(&info->lock);
1183	ret = param_set_bool(val, kp);
1184	if (ret) {
1185		mutex_unlock(&info->lock);
1186		return ret;
1187	} else if (dmatest_run) {
1188		if (!is_threaded_test_pending(info)) {
1189			/*
1190			 * We have nothing to run. This can be due to:
1191			 */
1192			ret = info->last_error;
1193			if (ret) {
1194				/* 1) Misconfiguration */
1195				pr_err("Channel misconfigured, can't continue\n");
1196				mutex_unlock(&info->lock);
1197				return ret;
1198			} else {
1199				/* 2) We rely on defaults */
1200				pr_info("No channels configured, continue with any\n");
1201				if (!is_threaded_test_run(info))
1202					stop_threaded_test(info);
1203				add_threaded_test(info);
1204			}
1205		}
1206		start_threaded_tests(info);
1207	} else {
1208		stop_threaded_test(info);
1209	}
1210
1211	mutex_unlock(&info->lock);
1212
1213	return ret;
1214}
1215
1216static int dmatest_chan_set(const char *val, const struct kernel_param *kp)
1217{
1218	struct dmatest_info *info = &test_info;
1219	struct dmatest_chan *dtc;
1220	char chan_reset_val[20];
1221	int ret;
1222
1223	mutex_lock(&info->lock);
1224	ret = param_set_copystring(val, kp);
1225	if (ret) {
1226		mutex_unlock(&info->lock);
1227		return ret;
1228	}
1229	/*Clear any previously run threads */
1230	if (!is_threaded_test_run(info) && !is_threaded_test_pending(info))
1231		stop_threaded_test(info);
1232	/* Reject channels that are already registered */
1233	if (is_threaded_test_pending(info)) {
1234		list_for_each_entry(dtc, &info->channels, node) {
1235			if (strcmp(dma_chan_name(dtc->chan),
1236				   strim(test_channel)) == 0) {
1237				dtc = list_last_entry(&info->channels,
1238						      struct dmatest_chan,
1239						      node);
1240				strlcpy(chan_reset_val,
1241					dma_chan_name(dtc->chan),
1242					sizeof(chan_reset_val));
1243				ret = -EBUSY;
1244				goto add_chan_err;
1245			}
1246		}
1247	}
1248
1249	add_threaded_test(info);
1250
1251	/* Check if channel was added successfully */
1252	dtc = list_last_entry(&info->channels, struct dmatest_chan, node);
1253
1254	if (dtc->chan) {
1255		/*
1256		 * if new channel was not successfully added, revert the
1257		 * "test_channel" string to the name of the last successfully
1258		 * added channel. exception for when users issues empty string
1259		 * to channel parameter.
1260		 */
1261		if ((strcmp(dma_chan_name(dtc->chan), strim(test_channel)) != 0)
1262		    && (strcmp("", strim(test_channel)) != 0)) {
1263			ret = -EINVAL;
1264			strlcpy(chan_reset_val, dma_chan_name(dtc->chan),
1265				sizeof(chan_reset_val));
1266			goto add_chan_err;
1267		}
1268
1269	} else {
1270		/* Clear test_channel if no channels were added successfully */
1271		strlcpy(chan_reset_val, "", sizeof(chan_reset_val));
1272		ret = -EBUSY;
1273		goto add_chan_err;
1274	}
1275
1276	info->last_error = ret;
1277	mutex_unlock(&info->lock);
1278
1279	return ret;
1280
1281add_chan_err:
1282	param_set_copystring(chan_reset_val, kp);
1283	info->last_error = ret;
1284	mutex_unlock(&info->lock);
1285
1286	return ret;
1287}
1288
1289static int dmatest_chan_get(char *val, const struct kernel_param *kp)
1290{
1291	struct dmatest_info *info = &test_info;
1292
1293	mutex_lock(&info->lock);
1294	if (!is_threaded_test_run(info) && !is_threaded_test_pending(info)) {
1295		stop_threaded_test(info);
1296		strlcpy(test_channel, "", sizeof(test_channel));
1297	}
1298	mutex_unlock(&info->lock);
1299
1300	return param_get_string(val, kp);
1301}
1302
1303static int dmatest_test_list_get(char *val, const struct kernel_param *kp)
1304{
1305	struct dmatest_info *info = &test_info;
1306	struct dmatest_chan *dtc;
1307	unsigned int thread_count = 0;
1308
1309	list_for_each_entry(dtc, &info->channels, node) {
1310		struct dmatest_thread *thread;
1311
1312		thread_count = 0;
1313		list_for_each_entry(thread, &dtc->threads, node) {
1314			thread_count++;
1315		}
1316		pr_info("%u threads using %s\n",
1317			thread_count, dma_chan_name(dtc->chan));
1318	}
1319
1320	return 0;
1321}
1322
1323static int __init dmatest_init(void)
1324{
1325	struct dmatest_info *info = &test_info;
1326	struct dmatest_params *params = &info->params;
1327
1328	if (dmatest_run) {
1329		mutex_lock(&info->lock);
1330		add_threaded_test(info);
1331		run_pending_tests(info);
1332		mutex_unlock(&info->lock);
1333	}
1334
1335	if (params->iterations && wait)
1336		wait_event(thread_wait, !is_threaded_test_run(info));
1337
1338	/* module parameters are stable, inittime tests are started,
1339	 * let userspace take over 'run' control
1340	 */
1341	info->did_init = true;
1342
1343	return 0;
1344}
1345/* when compiled-in wait for drivers to load first */
1346late_initcall(dmatest_init);
1347
1348static void __exit dmatest_exit(void)
1349{
1350	struct dmatest_info *info = &test_info;
1351
1352	mutex_lock(&info->lock);
1353	stop_threaded_test(info);
1354	mutex_unlock(&info->lock);
1355}
1356module_exit(dmatest_exit);
1357
1358MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1359MODULE_LICENSE("GPL v2");