1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  linux/drivers/spi/spi-loopback-test.c
4  *
5  *  (c) Martin Sperl <kernel@martin.sperl.org>
6  *
7  *  Loopback test driver to test several typical spi_message conditions
8  *  that a spi_master driver may encounter
9  *  this can also get used for regression testing
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/kernel.h>
14 #include <linux/ktime.h>
15 #include <linux/list.h>
16 #include <linux/list_sort.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/printk.h>
20 #include <linux/vmalloc.h>
21 #include <linux/spi/spi.h>
22 
23 #include "spi-test.h"
24 
25 /* flag to only simulate transfers */
26 static int simulate_only;
27 module_param(simulate_only, int, 0);
28 MODULE_PARM_DESC(simulate_only, "if not 0 do not execute the spi message");
29 
30 /* dump spi messages */
31 static int dump_messages;
32 module_param(dump_messages, int, 0);
33 MODULE_PARM_DESC(dump_messages,
34 		 "=1 dump the basic spi_message_structure, " \
35 		 "=2 dump the spi_message_structure including data, " \
36 		 "=3 dump the spi_message structure before and after execution");
37 /* the device is jumpered for loopback - enabling some rx_buf tests */
38 static int loopback;
39 module_param(loopback, int, 0);
40 MODULE_PARM_DESC(loopback,
41 		 "if set enable loopback mode, where the rx_buf "	\
42 		 "is checked to match tx_buf after the spi_message "	\
43 		 "is executed");
44 
45 static int loop_req;
46 module_param(loop_req, int, 0);
47 MODULE_PARM_DESC(loop_req,
48 		 "if set controller will be asked to enable test loop mode. " \
49 		 "If controller supported it, MISO and MOSI will be connected");
50 
51 static int no_cs;
52 module_param(no_cs, int, 0);
53 MODULE_PARM_DESC(no_cs,
54 		 "if set Chip Select (CS) will not be used");
55 
56 /* run only a specific test */
57 static int run_only_test = -1;
58 module_param(run_only_test, int, 0);
59 MODULE_PARM_DESC(run_only_test,
60 		 "only run the test with this number (0-based !)");
61 
62 /* use vmalloc'ed buffers */
63 static int use_vmalloc;
64 module_param(use_vmalloc, int, 0644);
65 MODULE_PARM_DESC(use_vmalloc,
66 		 "use vmalloc'ed buffers instead of kmalloc'ed");
67 
68 /* check rx ranges */
69 static int check_ranges = 1;
70 module_param(check_ranges, int, 0644);
71 MODULE_PARM_DESC(check_ranges,
72 		 "checks rx_buffer pattern are valid");
73 
74 /* the actual tests to execute */
75 static struct spi_test spi_tests[] = {
76 	{
77 		.description	= "tx/rx-transfer - start of page",
78 		.fill_option	= FILL_COUNT_8,
79 		.iterate_len    = { ITERATE_MAX_LEN },
80 		.iterate_tx_align = ITERATE_ALIGN,
81 		.iterate_rx_align = ITERATE_ALIGN,
82 		.transfer_count = 1,
83 		.transfers		= {
84 			{
85 				.tx_buf = TX(0),
86 				.rx_buf = RX(0),
87 			},
88 		},
89 	},
90 	{
91 		.description	= "tx/rx-transfer - crossing PAGE_SIZE",
92 		.fill_option	= FILL_COUNT_8,
93 		.iterate_len    = { ITERATE_MAX_LEN },
94 		.iterate_tx_align = ITERATE_ALIGN,
95 		.iterate_rx_align = ITERATE_ALIGN,
96 		.transfer_count = 1,
97 		.transfers		= {
98 			{
99 				.tx_buf = TX(PAGE_SIZE - 4),
100 				.rx_buf = RX(PAGE_SIZE - 4),
101 			},
102 		},
103 	},
104 	{
105 		.description	= "tx-transfer - only",
106 		.fill_option	= FILL_COUNT_8,
107 		.iterate_len    = { ITERATE_MAX_LEN },
108 		.iterate_tx_align = ITERATE_ALIGN,
109 		.transfer_count = 1,
110 		.transfers		= {
111 			{
112 				.tx_buf = TX(0),
113 			},
114 		},
115 	},
116 	{
117 		.description	= "rx-transfer - only",
118 		.fill_option	= FILL_COUNT_8,
119 		.iterate_len    = { ITERATE_MAX_LEN },
120 		.iterate_rx_align = ITERATE_ALIGN,
121 		.transfer_count = 1,
122 		.transfers		= {
123 			{
124 				.rx_buf = RX(0),
125 			},
126 		},
127 	},
128 	{
129 		.description	= "two tx-transfers - alter both",
130 		.fill_option	= FILL_COUNT_8,
131 		.iterate_len    = { ITERATE_LEN },
132 		.iterate_tx_align = ITERATE_ALIGN,
133 		.iterate_transfer_mask = BIT(0) | BIT(1),
134 		.transfer_count = 2,
135 		.transfers		= {
136 			{
137 				.tx_buf = TX(0),
138 			},
139 			{
140 				/* this is why we cant use ITERATE_MAX_LEN */
141 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
142 			},
143 		},
144 	},
145 	{
146 		.description	= "two tx-transfers - alter first",
147 		.fill_option	= FILL_COUNT_8,
148 		.iterate_len    = { ITERATE_MAX_LEN },
149 		.iterate_tx_align = ITERATE_ALIGN,
150 		.iterate_transfer_mask = BIT(0),
151 		.transfer_count = 2,
152 		.transfers		= {
153 			{
154 				.tx_buf = TX(64),
155 			},
156 			{
157 				.len = 1,
158 				.tx_buf = TX(0),
159 			},
160 		},
161 	},
162 	{
163 		.description	= "two tx-transfers - alter second",
164 		.fill_option	= FILL_COUNT_8,
165 		.iterate_len    = { ITERATE_MAX_LEN },
166 		.iterate_tx_align = ITERATE_ALIGN,
167 		.iterate_transfer_mask = BIT(1),
168 		.transfer_count = 2,
169 		.transfers		= {
170 			{
171 				.len = 16,
172 				.tx_buf = TX(0),
173 			},
174 			{
175 				.tx_buf = TX(64),
176 			},
177 		},
178 	},
179 	{
180 		.description	= "two transfers tx then rx - alter both",
181 		.fill_option	= FILL_COUNT_8,
182 		.iterate_len    = { ITERATE_MAX_LEN },
183 		.iterate_tx_align = ITERATE_ALIGN,
184 		.iterate_transfer_mask = BIT(0) | BIT(1),
185 		.transfer_count = 2,
186 		.transfers		= {
187 			{
188 				.tx_buf = TX(0),
189 			},
190 			{
191 				.rx_buf = RX(0),
192 			},
193 		},
194 	},
195 	{
196 		.description	= "two transfers tx then rx - alter tx",
197 		.fill_option	= FILL_COUNT_8,
198 		.iterate_len    = { ITERATE_MAX_LEN },
199 		.iterate_tx_align = ITERATE_ALIGN,
200 		.iterate_transfer_mask = BIT(0),
201 		.transfer_count = 2,
202 		.transfers		= {
203 			{
204 				.tx_buf = TX(0),
205 			},
206 			{
207 				.len = 1,
208 				.rx_buf = RX(0),
209 			},
210 		},
211 	},
212 	{
213 		.description	= "two transfers tx then rx - alter rx",
214 		.fill_option	= FILL_COUNT_8,
215 		.iterate_len    = { ITERATE_MAX_LEN },
216 		.iterate_tx_align = ITERATE_ALIGN,
217 		.iterate_transfer_mask = BIT(1),
218 		.transfer_count = 2,
219 		.transfers		= {
220 			{
221 				.len = 1,
222 				.tx_buf = TX(0),
223 			},
224 			{
225 				.rx_buf = RX(0),
226 			},
227 		},
228 	},
229 	{
230 		.description	= "two tx+rx transfers - alter both",
231 		.fill_option	= FILL_COUNT_8,
232 		.iterate_len    = { ITERATE_LEN },
233 		.iterate_tx_align = ITERATE_ALIGN,
234 		.iterate_transfer_mask = BIT(0) | BIT(1),
235 		.transfer_count = 2,
236 		.transfers		= {
237 			{
238 				.tx_buf = TX(0),
239 				.rx_buf = RX(0),
240 			},
241 			{
242 				/* making sure we align without overwrite
243 				 * the reason we can not use ITERATE_MAX_LEN
244 				 */
245 				.tx_buf = TX(SPI_TEST_MAX_SIZE_HALF),
246 				.rx_buf = RX(SPI_TEST_MAX_SIZE_HALF),
247 			},
248 		},
249 	},
250 	{
251 		.description	= "two tx+rx transfers - alter first",
252 		.fill_option	= FILL_COUNT_8,
253 		.iterate_len    = { ITERATE_MAX_LEN },
254 		.iterate_tx_align = ITERATE_ALIGN,
255 		.iterate_transfer_mask = BIT(0),
256 		.transfer_count = 2,
257 		.transfers		= {
258 			{
259 				/* making sure we align without overwrite */
260 				.tx_buf = TX(1024),
261 				.rx_buf = RX(1024),
262 			},
263 			{
264 				.len = 1,
265 				/* making sure we align without overwrite */
266 				.tx_buf = TX(0),
267 				.rx_buf = RX(0),
268 			},
269 		},
270 	},
271 	{
272 		.description	= "two tx+rx transfers - alter second",
273 		.fill_option	= FILL_COUNT_8,
274 		.iterate_len    = { ITERATE_MAX_LEN },
275 		.iterate_tx_align = ITERATE_ALIGN,
276 		.iterate_transfer_mask = BIT(1),
277 		.transfer_count = 2,
278 		.transfers		= {
279 			{
280 				.len = 1,
281 				.tx_buf = TX(0),
282 				.rx_buf = RX(0),
283 			},
284 			{
285 				/* making sure we align without overwrite */
286 				.tx_buf = TX(1024),
287 				.rx_buf = RX(1024),
288 			},
289 		},
290 	},
291 	{
292 		.description	= "two tx+rx transfers - delay after transfer",
293 		.fill_option	= FILL_COUNT_8,
294 		.iterate_len    = { ITERATE_MAX_LEN },
295 		.iterate_transfer_mask = BIT(0) | BIT(1),
296 		.transfer_count = 2,
297 		.transfers		= {
298 			{
299 				.tx_buf = TX(0),
300 				.rx_buf = RX(0),
301 				.delay_usecs = 1000,
302 			},
303 			{
304 				.tx_buf = TX(0),
305 				.rx_buf = RX(0),
306 				.delay_usecs = 1000,
307 			},
308 		},
309 	},
310 
311 	{ /* end of tests sequence */ }
312 };
313 
314 static int spi_loopback_test_probe(struct spi_device *spi)
315 {
316 	int ret;
317 
318 	if (loop_req || no_cs) {
319 		spi->mode |= loop_req ? SPI_LOOP : 0;
320 		spi->mode |= no_cs ? SPI_NO_CS : 0;
321 		ret = spi_setup(spi);
322 		if (ret) {
323 			dev_err(&spi->dev, "SPI setup with SPI_LOOP or SPI_NO_CS failed (%d)\n",
324 				ret);
325 			return ret;
326 		}
327 	}
328 
329 	dev_info(&spi->dev, "Executing spi-loopback-tests\n");
330 
331 	ret = spi_test_run_tests(spi, spi_tests);
332 
333 	dev_info(&spi->dev, "Finished spi-loopback-tests with return: %i\n",
334 		 ret);
335 
336 	return ret;
337 }
338 
339 /* non const match table to permit to change via a module parameter */
340 static struct of_device_id spi_loopback_test_of_match[] = {
341 	{ .compatible	= "linux,spi-loopback-test", },
342 	{ }
343 };
344 
345 /* allow to override the compatible string via a module_parameter */
346 module_param_string(compatible, spi_loopback_test_of_match[0].compatible,
347 		    sizeof(spi_loopback_test_of_match[0].compatible),
348 		    0000);
349 
350 MODULE_DEVICE_TABLE(of, spi_loopback_test_of_match);
351 
352 static struct spi_driver spi_loopback_test_driver = {
353 	.driver = {
354 		.name = "spi-loopback-test",
355 		.owner = THIS_MODULE,
356 		.of_match_table = spi_loopback_test_of_match,
357 	},
358 	.probe = spi_loopback_test_probe,
359 };
360 
361 module_spi_driver(spi_loopback_test_driver);
362 
363 MODULE_AUTHOR("Martin Sperl <kernel@martin.sperl.org>");
364 MODULE_DESCRIPTION("test spi_driver to check core functionality");
365 MODULE_LICENSE("GPL");
366 
367 /*-------------------------------------------------------------------------*/
368 
369 /* spi_test implementation */
370 
371 #define RANGE_CHECK(ptr, plen, start, slen) \
372 	((ptr >= start) && (ptr + plen <= start + slen))
373 
374 /* we allocate one page more, to allow for offsets */
375 #define SPI_TEST_MAX_SIZE_PLUS (SPI_TEST_MAX_SIZE + PAGE_SIZE)
376 
377 static void spi_test_print_hex_dump(char *pre, const void *ptr, size_t len)
378 {
379 	/* limit the hex_dump */
380 	if (len < 1024) {
381 		print_hex_dump(KERN_INFO, pre,
382 			       DUMP_PREFIX_OFFSET, 16, 1,
383 			       ptr, len, 0);
384 		return;
385 	}
386 	/* print head */
387 	print_hex_dump(KERN_INFO, pre,
388 		       DUMP_PREFIX_OFFSET, 16, 1,
389 		       ptr, 512, 0);
390 	/* print tail */
391 	pr_info("%s truncated - continuing at offset %04zx\n",
392 		pre, len - 512);
393 	print_hex_dump(KERN_INFO, pre,
394 		       DUMP_PREFIX_OFFSET, 16, 1,
395 		       ptr + (len - 512), 512, 0);
396 }
397 
398 static void spi_test_dump_message(struct spi_device *spi,
399 				  struct spi_message *msg,
400 				  bool dump_data)
401 {
402 	struct spi_transfer *xfer;
403 	int i;
404 	u8 b;
405 
406 	dev_info(&spi->dev, "  spi_msg@%pK\n", msg);
407 	if (msg->status)
408 		dev_info(&spi->dev, "    status:        %i\n",
409 			 msg->status);
410 	dev_info(&spi->dev, "    frame_length:  %i\n",
411 		 msg->frame_length);
412 	dev_info(&spi->dev, "    actual_length: %i\n",
413 		 msg->actual_length);
414 
415 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
416 		dev_info(&spi->dev, "    spi_transfer@%pK\n", xfer);
417 		dev_info(&spi->dev, "      len:    %i\n", xfer->len);
418 		dev_info(&spi->dev, "      tx_buf: %pK\n", xfer->tx_buf);
419 		if (dump_data && xfer->tx_buf)
420 			spi_test_print_hex_dump("          TX: ",
421 						xfer->tx_buf,
422 						xfer->len);
423 
424 		dev_info(&spi->dev, "      rx_buf: %pK\n", xfer->rx_buf);
425 		if (dump_data && xfer->rx_buf)
426 			spi_test_print_hex_dump("          RX: ",
427 						xfer->rx_buf,
428 						xfer->len);
429 		/* check for unwritten test pattern on rx_buf */
430 		if (xfer->rx_buf) {
431 			for (i = 0 ; i < xfer->len ; i++) {
432 				b = ((u8 *)xfer->rx_buf)[xfer->len - 1 - i];
433 				if (b != SPI_TEST_PATTERN_UNWRITTEN)
434 					break;
435 			}
436 			if (i)
437 				dev_info(&spi->dev,
438 					 "      rx_buf filled with %02x starts at offset: %i\n",
439 					 SPI_TEST_PATTERN_UNWRITTEN,
440 					 xfer->len - i);
441 		}
442 	}
443 }
444 
445 struct rx_ranges {
446 	struct list_head list;
447 	u8 *start;
448 	u8 *end;
449 };
450 
451 static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b)
452 {
453 	struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list);
454 	struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list);
455 
456 	if (rx_a->start > rx_b->start)
457 		return 1;
458 	if (rx_a->start < rx_b->start)
459 		return -1;
460 	return 0;
461 }
462 
463 static int spi_check_rx_ranges(struct spi_device *spi,
464 			       struct spi_message *msg,
465 			       void *rx)
466 {
467 	struct spi_transfer *xfer;
468 	struct rx_ranges ranges[SPI_TEST_MAX_TRANSFERS], *r;
469 	int i = 0;
470 	LIST_HEAD(ranges_list);
471 	u8 *addr;
472 	int ret = 0;
473 
474 	/* loop over all transfers to fill in the rx_ranges */
475 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
476 		/* if there is no rx, then no check is needed */
477 		if (!xfer->rx_buf)
478 			continue;
479 		/* fill in the rx_range */
480 		if (RANGE_CHECK(xfer->rx_buf, xfer->len,
481 				rx, SPI_TEST_MAX_SIZE_PLUS)) {
482 			ranges[i].start = xfer->rx_buf;
483 			ranges[i].end = xfer->rx_buf + xfer->len;
484 			list_add(&ranges[i].list, &ranges_list);
485 			i++;
486 		}
487 	}
488 
489 	/* if no ranges, then we can return and avoid the checks...*/
490 	if (!i)
491 		return 0;
492 
493 	/* sort the list */
494 	list_sort(NULL, &ranges_list, rx_ranges_cmp);
495 
496 	/* and iterate over all the rx addresses */
497 	for (addr = rx; addr < (u8 *)rx + SPI_TEST_MAX_SIZE_PLUS; addr++) {
498 		/* if we are the DO not write pattern,
499 		 * then continue with the loop...
500 		 */
501 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
502 			continue;
503 
504 		/* check if we are inside a range */
505 		list_for_each_entry(r, &ranges_list, list) {
506 			/* if so then set to end... */
507 			if ((addr >= r->start) && (addr < r->end))
508 				addr = r->end;
509 		}
510 		/* second test after a (hopefull) translation */
511 		if (*addr == SPI_TEST_PATTERN_DO_NOT_WRITE)
512 			continue;
513 
514 		/* if still not found then something has modified too much */
515 		/* we could list the "closest" transfer here... */
516 		dev_err(&spi->dev,
517 			"loopback strangeness - rx changed outside of allowed range at: %pK\n",
518 			addr);
519 		/* do not return, only set ret,
520 		 * so that we list all addresses
521 		 */
522 		ret = -ERANGE;
523 	}
524 
525 	return ret;
526 }
527 
528 static int spi_test_check_elapsed_time(struct spi_device *spi,
529 				       struct spi_test *test)
530 {
531 	int i;
532 	unsigned long long estimated_time = 0;
533 	unsigned long long delay_usecs = 0;
534 
535 	for (i = 0; i < test->transfer_count; i++) {
536 		struct spi_transfer *xfer = test->transfers + i;
537 		unsigned long long nbits = (unsigned long long)BITS_PER_BYTE *
538 					   xfer->len;
539 
540 		delay_usecs += xfer->delay_usecs;
541 		if (!xfer->speed_hz)
542 			continue;
543 		estimated_time += div_u64(nbits * NSEC_PER_SEC, xfer->speed_hz);
544 	}
545 
546 	estimated_time += delay_usecs * NSEC_PER_USEC;
547 	if (test->elapsed_time < estimated_time) {
548 		dev_err(&spi->dev,
549 			"elapsed time %lld ns is shorter than minimum estimated time %lld ns\n",
550 			test->elapsed_time, estimated_time);
551 
552 		return -EINVAL;
553 	}
554 
555 	return 0;
556 }
557 
558 static int spi_test_check_loopback_result(struct spi_device *spi,
559 					  struct spi_message *msg,
560 					  void *tx, void *rx)
561 {
562 	struct spi_transfer *xfer;
563 	u8 rxb, txb;
564 	size_t i;
565 	int ret;
566 
567 	/* checks rx_buffer pattern are valid with loopback or without */
568 	if (check_ranges) {
569 		ret = spi_check_rx_ranges(spi, msg, rx);
570 		if (ret)
571 			return ret;
572 	}
573 
574 	/* if we run without loopback, then return now */
575 	if (!loopback)
576 		return 0;
577 
578 	/* if applicable to transfer check that rx_buf is equal to tx_buf */
579 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
580 		/* if there is no rx, then no check is needed */
581 		if (!xfer->len || !xfer->rx_buf)
582 			continue;
583 		/* so depending on tx_buf we need to handle things */
584 		if (xfer->tx_buf) {
585 			for (i = 0; i < xfer->len; i++) {
586 				txb = ((u8 *)xfer->tx_buf)[i];
587 				rxb = ((u8 *)xfer->rx_buf)[i];
588 				if (txb != rxb)
589 					goto mismatch_error;
590 			}
591 		} else {
592 			/* first byte received */
593 			txb = ((u8 *)xfer->rx_buf)[0];
594 			/* first byte may be 0 or xff */
595 			if (!((txb == 0) || (txb == 0xff))) {
596 				dev_err(&spi->dev,
597 					"loopback strangeness - we expect 0x00 or 0xff, but not 0x%02x\n",
598 					txb);
599 				return -EINVAL;
600 			}
601 			/* check that all bytes are identical */
602 			for (i = 1; i < xfer->len; i++) {
603 				rxb = ((u8 *)xfer->rx_buf)[i];
604 				if (rxb != txb)
605 					goto mismatch_error;
606 			}
607 		}
608 	}
609 
610 	return 0;
611 
612 mismatch_error:
613 	dev_err(&spi->dev,
614 		"loopback strangeness - transfer mismatch on byte %04zx - expected 0x%02x, but got 0x%02x\n",
615 		i, txb, rxb);
616 
617 	return -EINVAL;
618 }
619 
620 static int spi_test_translate(struct spi_device *spi,
621 			      void **ptr, size_t len,
622 			      void *tx, void *rx)
623 {
624 	size_t off;
625 
626 	/* return on null */
627 	if (!*ptr)
628 		return 0;
629 
630 	/* in the MAX_SIZE_HALF case modify the pointer */
631 	if (((size_t)*ptr) & SPI_TEST_MAX_SIZE_HALF)
632 		/* move the pointer to the correct range */
633 		*ptr += (SPI_TEST_MAX_SIZE_PLUS / 2) -
634 			SPI_TEST_MAX_SIZE_HALF;
635 
636 	/* RX range
637 	 * - we check against MAX_SIZE_PLUS to allow for automated alignment
638 	 */
639 	if (RANGE_CHECK(*ptr, len,  RX(0), SPI_TEST_MAX_SIZE_PLUS)) {
640 		off = *ptr - RX(0);
641 		*ptr = rx + off;
642 
643 		return 0;
644 	}
645 
646 	/* TX range */
647 	if (RANGE_CHECK(*ptr, len,  TX(0), SPI_TEST_MAX_SIZE_PLUS)) {
648 		off = *ptr - TX(0);
649 		*ptr = tx + off;
650 
651 		return 0;
652 	}
653 
654 	dev_err(&spi->dev,
655 		"PointerRange [%pK:%pK[ not in range [%pK:%pK[ or [%pK:%pK[\n",
656 		*ptr, *ptr + len,
657 		RX(0), RX(SPI_TEST_MAX_SIZE),
658 		TX(0), TX(SPI_TEST_MAX_SIZE));
659 
660 	return -EINVAL;
661 }
662 
663 static int spi_test_fill_pattern(struct spi_device *spi,
664 				 struct spi_test *test)
665 {
666 	struct spi_transfer *xfers = test->transfers;
667 	u8 *tx_buf;
668 	size_t count = 0;
669 	int i, j;
670 
671 #ifdef __BIG_ENDIAN
672 #define GET_VALUE_BYTE(value, index, bytes) \
673 	(value >> (8 * (bytes - 1 - count % bytes)))
674 #else
675 #define GET_VALUE_BYTE(value, index, bytes) \
676 	(value >> (8 * (count % bytes)))
677 #endif
678 
679 	/* fill all transfers with the pattern requested */
680 	for (i = 0; i < test->transfer_count; i++) {
681 		/* fill rx_buf with SPI_TEST_PATTERN_UNWRITTEN */
682 		if (xfers[i].rx_buf)
683 			memset(xfers[i].rx_buf, SPI_TEST_PATTERN_UNWRITTEN,
684 			       xfers[i].len);
685 		/* if tx_buf is NULL then skip */
686 		tx_buf = (u8 *)xfers[i].tx_buf;
687 		if (!tx_buf)
688 			continue;
689 		/* modify all the transfers */
690 		for (j = 0; j < xfers[i].len; j++, tx_buf++, count++) {
691 			/* fill tx */
692 			switch (test->fill_option) {
693 			case FILL_MEMSET_8:
694 				*tx_buf = test->fill_pattern;
695 				break;
696 			case FILL_MEMSET_16:
697 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
698 							 count, 2);
699 				break;
700 			case FILL_MEMSET_24:
701 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
702 							 count, 3);
703 				break;
704 			case FILL_MEMSET_32:
705 				*tx_buf = GET_VALUE_BYTE(test->fill_pattern,
706 							 count, 4);
707 				break;
708 			case FILL_COUNT_8:
709 				*tx_buf = count;
710 				break;
711 			case FILL_COUNT_16:
712 				*tx_buf = GET_VALUE_BYTE(count, count, 2);
713 				break;
714 			case FILL_COUNT_24:
715 				*tx_buf = GET_VALUE_BYTE(count, count, 3);
716 				break;
717 			case FILL_COUNT_32:
718 				*tx_buf = GET_VALUE_BYTE(count, count, 4);
719 				break;
720 			case FILL_TRANSFER_BYTE_8:
721 				*tx_buf = j;
722 				break;
723 			case FILL_TRANSFER_BYTE_16:
724 				*tx_buf = GET_VALUE_BYTE(j, j, 2);
725 				break;
726 			case FILL_TRANSFER_BYTE_24:
727 				*tx_buf = GET_VALUE_BYTE(j, j, 3);
728 				break;
729 			case FILL_TRANSFER_BYTE_32:
730 				*tx_buf = GET_VALUE_BYTE(j, j, 4);
731 				break;
732 			case FILL_TRANSFER_NUM:
733 				*tx_buf = i;
734 				break;
735 			default:
736 				dev_err(&spi->dev,
737 					"unsupported fill_option: %i\n",
738 					test->fill_option);
739 				return -EINVAL;
740 			}
741 		}
742 	}
743 
744 	return 0;
745 }
746 
747 static int _spi_test_run_iter(struct spi_device *spi,
748 			      struct spi_test *test,
749 			      void *tx, void *rx)
750 {
751 	struct spi_message *msg = &test->msg;
752 	struct spi_transfer *x;
753 	int i, ret;
754 
755 	/* initialize message - zero-filled via static initialization */
756 	spi_message_init_no_memset(msg);
757 
758 	/* fill rx with the DO_NOT_WRITE pattern */
759 	memset(rx, SPI_TEST_PATTERN_DO_NOT_WRITE, SPI_TEST_MAX_SIZE_PLUS);
760 
761 	/* add the individual transfers */
762 	for (i = 0; i < test->transfer_count; i++) {
763 		x = &test->transfers[i];
764 
765 		/* patch the values of tx_buf */
766 		ret = spi_test_translate(spi, (void **)&x->tx_buf, x->len,
767 					 (void *)tx, rx);
768 		if (ret)
769 			return ret;
770 
771 		/* patch the values of rx_buf */
772 		ret = spi_test_translate(spi, &x->rx_buf, x->len,
773 					 (void *)tx, rx);
774 		if (ret)
775 			return ret;
776 
777 		/* and add it to the list */
778 		spi_message_add_tail(x, msg);
779 	}
780 
781 	/* fill in the transfer buffers with pattern */
782 	ret = spi_test_fill_pattern(spi, test);
783 	if (ret)
784 		return ret;
785 
786 	/* and execute */
787 	if (test->execute_msg)
788 		ret = test->execute_msg(spi, test, tx, rx);
789 	else
790 		ret = spi_test_execute_msg(spi, test, tx, rx);
791 
792 	/* handle result */
793 	if (ret == test->expected_return)
794 		return 0;
795 
796 	dev_err(&spi->dev,
797 		"test failed - test returned %i, but we expect %i\n",
798 		ret, test->expected_return);
799 
800 	if (ret)
801 		return ret;
802 
803 	/* if it is 0, as we expected something else,
804 	 * then return something special
805 	 */
806 	return -EFAULT;
807 }
808 
809 static int spi_test_run_iter(struct spi_device *spi,
810 			     const struct spi_test *testtemplate,
811 			     void *tx, void *rx,
812 			     size_t len,
813 			     size_t tx_off,
814 			     size_t rx_off
815 	)
816 {
817 	struct spi_test test;
818 	int i, tx_count, rx_count;
819 
820 	/* copy the test template to test */
821 	memcpy(&test, testtemplate, sizeof(test));
822 
823 	/* if iterate_transfer_mask is not set,
824 	 * then set it to first transfer only
825 	 */
826 	if (!(test.iterate_transfer_mask & (BIT(test.transfer_count) - 1)))
827 		test.iterate_transfer_mask = 1;
828 
829 	/* count number of transfers with tx/rx_buf != NULL */
830 	rx_count = tx_count = 0;
831 	for (i = 0; i < test.transfer_count; i++) {
832 		if (test.transfers[i].tx_buf)
833 			tx_count++;
834 		if (test.transfers[i].rx_buf)
835 			rx_count++;
836 	}
837 
838 	/* in some iteration cases warn and exit early,
839 	 * as there is nothing to do, that has not been tested already...
840 	 */
841 	if (tx_off && (!tx_count)) {
842 		dev_warn_once(&spi->dev,
843 			      "%s: iterate_tx_off configured with tx_buf==NULL - ignoring\n",
844 			      test.description);
845 		return 0;
846 	}
847 	if (rx_off && (!rx_count)) {
848 		dev_warn_once(&spi->dev,
849 			      "%s: iterate_rx_off configured with rx_buf==NULL - ignoring\n",
850 			      test.description);
851 		return 0;
852 	}
853 
854 	/* write out info */
855 	if (!(len || tx_off || rx_off)) {
856 		dev_info(&spi->dev, "Running test %s\n", test.description);
857 	} else {
858 		dev_info(&spi->dev,
859 			 "  with iteration values: len = %zu, tx_off = %zu, rx_off = %zu\n",
860 			 len, tx_off, rx_off);
861 	}
862 
863 	/* update in the values from iteration values */
864 	for (i = 0; i < test.transfer_count; i++) {
865 		/* only when bit in transfer mask is set */
866 		if (!(test.iterate_transfer_mask & BIT(i)))
867 			continue;
868 		test.transfers[i].len = len;
869 		if (test.transfers[i].tx_buf)
870 			test.transfers[i].tx_buf += tx_off;
871 		if (test.transfers[i].tx_buf)
872 			test.transfers[i].rx_buf += rx_off;
873 	}
874 
875 	/* and execute */
876 	return _spi_test_run_iter(spi, &test, tx, rx);
877 }
878 
879 /**
880  * spi_test_execute_msg - default implementation to run a test
881  *
882  * spi: @spi_device on which to run the @spi_message
883  * test: the test to execute, which already contains @msg
884  * tx:   the tx buffer allocated for the test sequence
885  * rx:   the rx buffer allocated for the test sequence
886  *
887  * Returns: error code of spi_sync as well as basic error checking
888  */
889 int spi_test_execute_msg(struct spi_device *spi, struct spi_test *test,
890 			 void *tx, void *rx)
891 {
892 	struct spi_message *msg = &test->msg;
893 	int ret = 0;
894 	int i;
895 
896 	/* only if we do not simulate */
897 	if (!simulate_only) {
898 		ktime_t start;
899 
900 		/* dump the complete message before and after the transfer */
901 		if (dump_messages == 3)
902 			spi_test_dump_message(spi, msg, true);
903 
904 		start = ktime_get();
905 		/* run spi message */
906 		ret = spi_sync(spi, msg);
907 		test->elapsed_time = ktime_to_ns(ktime_sub(ktime_get(), start));
908 		if (ret == -ETIMEDOUT) {
909 			dev_info(&spi->dev,
910 				 "spi-message timed out - rerunning...\n");
911 			/* rerun after a few explicit schedules */
912 			for (i = 0; i < 16; i++)
913 				schedule();
914 			ret = spi_sync(spi, msg);
915 		}
916 		if (ret) {
917 			dev_err(&spi->dev,
918 				"Failed to execute spi_message: %i\n",
919 				ret);
920 			goto exit;
921 		}
922 
923 		/* do some extra error checks */
924 		if (msg->frame_length != msg->actual_length) {
925 			dev_err(&spi->dev,
926 				"actual length differs from expected\n");
927 			ret = -EIO;
928 			goto exit;
929 		}
930 
931 		/* run rx-buffer tests */
932 		ret = spi_test_check_loopback_result(spi, msg, tx, rx);
933 		if (ret)
934 			goto exit;
935 
936 		ret = spi_test_check_elapsed_time(spi, test);
937 	}
938 
939 	/* if requested or on error dump message (including data) */
940 exit:
941 	if (dump_messages || ret)
942 		spi_test_dump_message(spi, msg,
943 				      (dump_messages >= 2) || (ret));
944 
945 	return ret;
946 }
947 EXPORT_SYMBOL_GPL(spi_test_execute_msg);
948 
949 /**
950  * spi_test_run_test - run an individual spi_test
951  *                     including all the relevant iterations on:
952  *                     length and buffer alignment
953  *
954  * spi:  the spi_device to send the messages to
955  * test: the test which we need to execute
956  * tx:   the tx buffer allocated for the test sequence
957  * rx:   the rx buffer allocated for the test sequence
958  *
959  * Returns: status code of spi_sync or other failures
960  */
961 
962 int spi_test_run_test(struct spi_device *spi, const struct spi_test *test,
963 		      void *tx, void *rx)
964 {
965 	int idx_len;
966 	size_t len;
967 	size_t tx_align, rx_align;
968 	int ret;
969 
970 	/* test for transfer limits */
971 	if (test->transfer_count >= SPI_TEST_MAX_TRANSFERS) {
972 		dev_err(&spi->dev,
973 			"%s: Exceeded max number of transfers with %i\n",
974 			test->description, test->transfer_count);
975 		return -E2BIG;
976 	}
977 
978 	/* setting up some values in spi_message
979 	 * based on some settings in spi_master
980 	 * some of this can also get done in the run() method
981 	 */
982 
983 	/* iterate over all the iterable values using macros
984 	 * (to make it a bit more readable...
985 	 */
986 #define FOR_EACH_ALIGNMENT(var)						\
987 	for (var = 0;							\
988 	    var < (test->iterate_##var ?				\
989 			(spi->master->dma_alignment ?			\
990 			 spi->master->dma_alignment :			\
991 			 test->iterate_##var) :				\
992 			1);						\
993 	    var++)
994 
995 	for (idx_len = 0; idx_len < SPI_TEST_MAX_ITERATE &&
996 	     (len = test->iterate_len[idx_len]) != -1; idx_len++) {
997 		FOR_EACH_ALIGNMENT(tx_align) {
998 			FOR_EACH_ALIGNMENT(rx_align) {
999 				/* and run the iteration */
1000 				ret = spi_test_run_iter(spi, test,
1001 							tx, rx,
1002 							len,
1003 							tx_align,
1004 							rx_align);
1005 				if (ret)
1006 					return ret;
1007 			}
1008 		}
1009 	}
1010 
1011 	return 0;
1012 }
1013 EXPORT_SYMBOL_GPL(spi_test_run_test);
1014 
1015 /**
1016  * spi_test_run_tests - run an array of spi_messages tests
1017  * @spi: the spi device on which to run the tests
1018  * @tests: NULL-terminated array of @spi_test
1019  *
1020  * Returns: status errors as per @spi_test_run_test()
1021  */
1022 
1023 int spi_test_run_tests(struct spi_device *spi,
1024 		       struct spi_test *tests)
1025 {
1026 	char *rx = NULL, *tx = NULL;
1027 	int ret = 0, count = 0;
1028 	struct spi_test *test;
1029 
1030 	/* allocate rx/tx buffers of 128kB size without devm
1031 	 * in the hope that is on a page boundary
1032 	 */
1033 	if (use_vmalloc)
1034 		rx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1035 	else
1036 		rx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1037 	if (!rx)
1038 		return -ENOMEM;
1039 
1040 
1041 	if (use_vmalloc)
1042 		tx = vmalloc(SPI_TEST_MAX_SIZE_PLUS);
1043 	else
1044 		tx = kzalloc(SPI_TEST_MAX_SIZE_PLUS, GFP_KERNEL);
1045 	if (!tx) {
1046 		ret = -ENOMEM;
1047 		goto err_tx;
1048 	}
1049 
1050 	/* now run the individual tests in the table */
1051 	for (test = tests, count = 0; test->description[0];
1052 	     test++, count++) {
1053 		/* only run test if requested */
1054 		if ((run_only_test > -1) && (count != run_only_test))
1055 			continue;
1056 		/* run custom implementation */
1057 		if (test->run_test)
1058 			ret = test->run_test(spi, test, tx, rx);
1059 		else
1060 			ret = spi_test_run_test(spi, test, tx, rx);
1061 		if (ret)
1062 			goto out;
1063 		/* add some delays so that we can easily
1064 		 * detect the individual tests when using a logic analyzer
1065 		 * we also add scheduling to avoid potential spi_timeouts...
1066 		 */
1067 		mdelay(100);
1068 		schedule();
1069 	}
1070 
1071 out:
1072 	kvfree(tx);
1073 err_tx:
1074 	kvfree(rx);
1075 	return ret;
1076 }
1077 EXPORT_SYMBOL_GPL(spi_test_run_tests);
1078