1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * davinci_nand.c - NAND Flash Driver for DaVinci family chips
4 *
5 * Copyright © 2006 Texas Instruments.
6 *
7 * Port to 2.6.23 Copyright © 2008 by:
8 *   Sander Huijsen <Shuijsen@optelecom-nkf.com>
9 *   Troy Kisky <troy.kisky@boundarydevices.com>
10 *   Dirk Behme <Dirk.Behme@gmail.com>
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/err.h>
17#include <linux/iopoll.h>
18#include <linux/mtd/rawnand.h>
19#include <linux/mtd/partitions.h>
20#include <linux/slab.h>
21#include <linux/of_device.h>
22#include <linux/of.h>
23
24#include <linux/platform_data/mtd-davinci.h>
25#include <linux/platform_data/mtd-davinci-aemif.h>
26
27/*
28 * This is a device driver for the NAND flash controller found on the
29 * various DaVinci family chips.  It handles up to four SoC chipselects,
30 * and some flavors of secondary chipselect (e.g. based on A12) as used
31 * with multichip packages.
32 *
33 * The 1-bit ECC hardware is supported, as well as the newer 4-bit ECC
34 * available on chips like the DM355 and OMAP-L137 and needed with the
35 * more error-prone MLC NAND chips.
36 *
37 * This driver assumes EM_WAIT connects all the NAND devices' RDY/nBUSY
38 * outputs in a "wire-AND" configuration, with no per-chip signals.
39 */
40struct davinci_nand_info {
41	struct nand_controller	controller;
42	struct nand_chip	chip;
43
44	struct platform_device	*pdev;
45
46	bool			is_readmode;
47
48	void __iomem		*base;
49	void __iomem		*vaddr;
50
51	void __iomem		*current_cs;
52
53	uint32_t		mask_chipsel;
54	uint32_t		mask_ale;
55	uint32_t		mask_cle;
56
57	uint32_t		core_chipsel;
58
59	struct davinci_aemif_timing	*timing;
60};
61
62static DEFINE_SPINLOCK(davinci_nand_lock);
63static bool ecc4_busy;
64
65static inline struct davinci_nand_info *to_davinci_nand(struct mtd_info *mtd)
66{
67	return container_of(mtd_to_nand(mtd), struct davinci_nand_info, chip);
68}
69
70static inline unsigned int davinci_nand_readl(struct davinci_nand_info *info,
71		int offset)
72{
73	return __raw_readl(info->base + offset);
74}
75
76static inline void davinci_nand_writel(struct davinci_nand_info *info,
77		int offset, unsigned long value)
78{
79	__raw_writel(value, info->base + offset);
80}
81
82/*----------------------------------------------------------------------*/
83
84/*
85 * 1-bit hardware ECC ... context maintained for each core chipselect
86 */
87
88static inline uint32_t nand_davinci_readecc_1bit(struct mtd_info *mtd)
89{
90	struct davinci_nand_info *info = to_davinci_nand(mtd);
91
92	return davinci_nand_readl(info, NANDF1ECC_OFFSET
93			+ 4 * info->core_chipsel);
94}
95
96static void nand_davinci_hwctl_1bit(struct nand_chip *chip, int mode)
97{
98	struct davinci_nand_info *info;
99	uint32_t nandcfr;
100	unsigned long flags;
101
102	info = to_davinci_nand(nand_to_mtd(chip));
103
104	/* Reset ECC hardware */
105	nand_davinci_readecc_1bit(nand_to_mtd(chip));
106
107	spin_lock_irqsave(&davinci_nand_lock, flags);
108
109	/* Restart ECC hardware */
110	nandcfr = davinci_nand_readl(info, NANDFCR_OFFSET);
111	nandcfr |= BIT(8 + info->core_chipsel);
112	davinci_nand_writel(info, NANDFCR_OFFSET, nandcfr);
113
114	spin_unlock_irqrestore(&davinci_nand_lock, flags);
115}
116
117/*
118 * Read hardware ECC value and pack into three bytes
119 */
120static int nand_davinci_calculate_1bit(struct nand_chip *chip,
121				       const u_char *dat, u_char *ecc_code)
122{
123	unsigned int ecc_val = nand_davinci_readecc_1bit(nand_to_mtd(chip));
124	unsigned int ecc24 = (ecc_val & 0x0fff) | ((ecc_val & 0x0fff0000) >> 4);
125
126	/* invert so that erased block ecc is correct */
127	ecc24 = ~ecc24;
128	ecc_code[0] = (u_char)(ecc24);
129	ecc_code[1] = (u_char)(ecc24 >> 8);
130	ecc_code[2] = (u_char)(ecc24 >> 16);
131
132	return 0;
133}
134
135static int nand_davinci_correct_1bit(struct nand_chip *chip, u_char *dat,
136				     u_char *read_ecc, u_char *calc_ecc)
137{
138	uint32_t eccNand = read_ecc[0] | (read_ecc[1] << 8) |
139					  (read_ecc[2] << 16);
140	uint32_t eccCalc = calc_ecc[0] | (calc_ecc[1] << 8) |
141					  (calc_ecc[2] << 16);
142	uint32_t diff = eccCalc ^ eccNand;
143
144	if (diff) {
145		if ((((diff >> 12) ^ diff) & 0xfff) == 0xfff) {
146			/* Correctable error */
147			if ((diff >> (12 + 3)) < chip->ecc.size) {
148				dat[diff >> (12 + 3)] ^= BIT((diff >> 12) & 7);
149				return 1;
150			} else {
151				return -EBADMSG;
152			}
153		} else if (!(diff & (diff - 1))) {
154			/* Single bit ECC error in the ECC itself,
155			 * nothing to fix */
156			return 1;
157		} else {
158			/* Uncorrectable error */
159			return -EBADMSG;
160		}
161
162	}
163	return 0;
164}
165
166/*----------------------------------------------------------------------*/
167
168/*
169 * 4-bit hardware ECC ... context maintained over entire AEMIF
170 *
171 * This is a syndrome engine, but we avoid NAND_ECC_PLACEMENT_INTERLEAVED
172 * since that forces use of a problematic "infix OOB" layout.
173 * Among other things, it trashes manufacturer bad block markers.
174 * Also, and specific to this hardware, it ECC-protects the "prepad"
175 * in the OOB ... while having ECC protection for parts of OOB would
176 * seem useful, the current MTD stack sometimes wants to update the
177 * OOB without recomputing ECC.
178 */
179
180static void nand_davinci_hwctl_4bit(struct nand_chip *chip, int mode)
181{
182	struct davinci_nand_info *info = to_davinci_nand(nand_to_mtd(chip));
183	unsigned long flags;
184	u32 val;
185
186	/* Reset ECC hardware */
187	davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET);
188
189	spin_lock_irqsave(&davinci_nand_lock, flags);
190
191	/* Start 4-bit ECC calculation for read/write */
192	val = davinci_nand_readl(info, NANDFCR_OFFSET);
193	val &= ~(0x03 << 4);
194	val |= (info->core_chipsel << 4) | BIT(12);
195	davinci_nand_writel(info, NANDFCR_OFFSET, val);
196
197	info->is_readmode = (mode == NAND_ECC_READ);
198
199	spin_unlock_irqrestore(&davinci_nand_lock, flags);
200}
201
202/* Read raw ECC code after writing to NAND. */
203static void
204nand_davinci_readecc_4bit(struct davinci_nand_info *info, u32 code[4])
205{
206	const u32 mask = 0x03ff03ff;
207
208	code[0] = davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET) & mask;
209	code[1] = davinci_nand_readl(info, NAND_4BIT_ECC2_OFFSET) & mask;
210	code[2] = davinci_nand_readl(info, NAND_4BIT_ECC3_OFFSET) & mask;
211	code[3] = davinci_nand_readl(info, NAND_4BIT_ECC4_OFFSET) & mask;
212}
213
214/* Terminate read ECC; or return ECC (as bytes) of data written to NAND. */
215static int nand_davinci_calculate_4bit(struct nand_chip *chip,
216				       const u_char *dat, u_char *ecc_code)
217{
218	struct davinci_nand_info *info = to_davinci_nand(nand_to_mtd(chip));
219	u32 raw_ecc[4], *p;
220	unsigned i;
221
222	/* After a read, terminate ECC calculation by a dummy read
223	 * of some 4-bit ECC register.  ECC covers everything that
224	 * was read; correct() just uses the hardware state, so
225	 * ecc_code is not needed.
226	 */
227	if (info->is_readmode) {
228		davinci_nand_readl(info, NAND_4BIT_ECC1_OFFSET);
229		return 0;
230	}
231
232	/* Pack eight raw 10-bit ecc values into ten bytes, making
233	 * two passes which each convert four values (in upper and
234	 * lower halves of two 32-bit words) into five bytes.  The
235	 * ROM boot loader uses this same packing scheme.
236	 */
237	nand_davinci_readecc_4bit(info, raw_ecc);
238	for (i = 0, p = raw_ecc; i < 2; i++, p += 2) {
239		*ecc_code++ =   p[0]        & 0xff;
240		*ecc_code++ = ((p[0] >>  8) & 0x03) | ((p[0] >> 14) & 0xfc);
241		*ecc_code++ = ((p[0] >> 22) & 0x0f) | ((p[1] <<  4) & 0xf0);
242		*ecc_code++ = ((p[1] >>  4) & 0x3f) | ((p[1] >> 10) & 0xc0);
243		*ecc_code++ =  (p[1] >> 18) & 0xff;
244	}
245
246	return 0;
247}
248
249/* Correct up to 4 bits in data we just read, using state left in the
250 * hardware plus the ecc_code computed when it was first written.
251 */
252static int nand_davinci_correct_4bit(struct nand_chip *chip, u_char *data,
253				     u_char *ecc_code, u_char *null)
254{
255	int i;
256	struct davinci_nand_info *info = to_davinci_nand(nand_to_mtd(chip));
257	unsigned short ecc10[8];
258	unsigned short *ecc16;
259	u32 syndrome[4];
260	u32 ecc_state;
261	unsigned num_errors, corrected;
262	unsigned long timeo;
263
264	/* Unpack ten bytes into eight 10 bit values.  We know we're
265	 * little-endian, and use type punning for less shifting/masking.
266	 */
267	if (WARN_ON(0x01 & (uintptr_t)ecc_code))
268		return -EINVAL;
269	ecc16 = (unsigned short *)ecc_code;
270
271	ecc10[0] =  (ecc16[0] >>  0) & 0x3ff;
272	ecc10[1] = ((ecc16[0] >> 10) & 0x3f) | ((ecc16[1] << 6) & 0x3c0);
273	ecc10[2] =  (ecc16[1] >>  4) & 0x3ff;
274	ecc10[3] = ((ecc16[1] >> 14) & 0x3)  | ((ecc16[2] << 2) & 0x3fc);
275	ecc10[4] =  (ecc16[2] >>  8)         | ((ecc16[3] << 8) & 0x300);
276	ecc10[5] =  (ecc16[3] >>  2) & 0x3ff;
277	ecc10[6] = ((ecc16[3] >> 12) & 0xf)  | ((ecc16[4] << 4) & 0x3f0);
278	ecc10[7] =  (ecc16[4] >>  6) & 0x3ff;
279
280	/* Tell ECC controller about the expected ECC codes. */
281	for (i = 7; i >= 0; i--)
282		davinci_nand_writel(info, NAND_4BIT_ECC_LOAD_OFFSET, ecc10[i]);
283
284	/* Allow time for syndrome calculation ... then read it.
285	 * A syndrome of all zeroes 0 means no detected errors.
286	 */
287	davinci_nand_readl(info, NANDFSR_OFFSET);
288	nand_davinci_readecc_4bit(info, syndrome);
289	if (!(syndrome[0] | syndrome[1] | syndrome[2] | syndrome[3]))
290		return 0;
291
292	/*
293	 * Clear any previous address calculation by doing a dummy read of an
294	 * error address register.
295	 */
296	davinci_nand_readl(info, NAND_ERR_ADD1_OFFSET);
297
298	/* Start address calculation, and wait for it to complete.
299	 * We _could_ start reading more data while this is working,
300	 * to speed up the overall page read.
301	 */
302	davinci_nand_writel(info, NANDFCR_OFFSET,
303			davinci_nand_readl(info, NANDFCR_OFFSET) | BIT(13));
304
305	/*
306	 * ECC_STATE field reads 0x3 (Error correction complete) immediately
307	 * after setting the 4BITECC_ADD_CALC_START bit. So if you immediately
308	 * begin trying to poll for the state, you may fall right out of your
309	 * loop without any of the correction calculations having taken place.
310	 * The recommendation from the hardware team is to initially delay as
311	 * long as ECC_STATE reads less than 4. After that, ECC HW has entered
312	 * correction state.
313	 */
314	timeo = jiffies + usecs_to_jiffies(100);
315	do {
316		ecc_state = (davinci_nand_readl(info,
317				NANDFSR_OFFSET) >> 8) & 0x0f;
318		cpu_relax();
319	} while ((ecc_state < 4) && time_before(jiffies, timeo));
320
321	for (;;) {
322		u32	fsr = davinci_nand_readl(info, NANDFSR_OFFSET);
323
324		switch ((fsr >> 8) & 0x0f) {
325		case 0:		/* no error, should not happen */
326			davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET);
327			return 0;
328		case 1:		/* five or more errors detected */
329			davinci_nand_readl(info, NAND_ERR_ERRVAL1_OFFSET);
330			return -EBADMSG;
331		case 2:		/* error addresses computed */
332		case 3:
333			num_errors = 1 + ((fsr >> 16) & 0x03);
334			goto correct;
335		default:	/* still working on it */
336			cpu_relax();
337			continue;
338		}
339	}
340
341correct:
342	/* correct each error */
343	for (i = 0, corrected = 0; i < num_errors; i++) {
344		int error_address, error_value;
345
346		if (i > 1) {
347			error_address = davinci_nand_readl(info,
348						NAND_ERR_ADD2_OFFSET);
349			error_value = davinci_nand_readl(info,
350						NAND_ERR_ERRVAL2_OFFSET);
351		} else {
352			error_address = davinci_nand_readl(info,
353						NAND_ERR_ADD1_OFFSET);
354			error_value = davinci_nand_readl(info,
355						NAND_ERR_ERRVAL1_OFFSET);
356		}
357
358		if (i & 1) {
359			error_address >>= 16;
360			error_value >>= 16;
361		}
362		error_address &= 0x3ff;
363		error_address = (512 + 7) - error_address;
364
365		if (error_address < 512) {
366			data[error_address] ^= error_value;
367			corrected++;
368		}
369	}
370
371	return corrected;
372}
373
374/**
375 * nand_davinci_read_page_hwecc_oob_first - Hardware ECC page read with ECC
376 *                                          data read from OOB area
377 * @chip: nand chip info structure
378 * @buf: buffer to store read data
379 * @oob_required: caller requires OOB data read to chip->oob_poi
380 * @page: page number to read
381 *
382 * Hardware ECC for large page chips, which requires the ECC data to be
383 * extracted from the OOB before the actual data is read.
384 */
385static int nand_davinci_read_page_hwecc_oob_first(struct nand_chip *chip,
386						  uint8_t *buf,
387						  int oob_required, int page)
388{
389	struct mtd_info *mtd = nand_to_mtd(chip);
390	int i, eccsize = chip->ecc.size, ret;
391	int eccbytes = chip->ecc.bytes;
392	int eccsteps = chip->ecc.steps;
393	uint8_t *p = buf;
394	uint8_t *ecc_code = chip->ecc.code_buf;
395	unsigned int max_bitflips = 0;
396
397	/* Read the OOB area first */
398	ret = nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
399	if (ret)
400		return ret;
401
402	/* Move read cursor to start of page */
403	ret = nand_change_read_column_op(chip, 0, NULL, 0, false);
404	if (ret)
405		return ret;
406
407	ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
408					 chip->ecc.total);
409	if (ret)
410		return ret;
411
412	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
413		int stat;
414
415		chip->ecc.hwctl(chip, NAND_ECC_READ);
416
417		ret = nand_read_data_op(chip, p, eccsize, false, false);
418		if (ret)
419			return ret;
420
421		stat = chip->ecc.correct(chip, p, &ecc_code[i], NULL);
422		if (stat == -EBADMSG &&
423		    (chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
424			/* check for empty pages with bitflips */
425			stat = nand_check_erased_ecc_chunk(p, eccsize,
426							   &ecc_code[i],
427							   eccbytes, NULL, 0,
428							   chip->ecc.strength);
429		}
430
431		if (stat < 0) {
432			mtd->ecc_stats.failed++;
433		} else {
434			mtd->ecc_stats.corrected += stat;
435			max_bitflips = max_t(unsigned int, max_bitflips, stat);
436		}
437	}
438	return max_bitflips;
439}
440
441/*----------------------------------------------------------------------*/
442
443/* An ECC layout for using 4-bit ECC with small-page flash, storing
444 * ten ECC bytes plus the manufacturer's bad block marker byte, and
445 * and not overlapping the default BBT markers.
446 */
447static int hwecc4_ooblayout_small_ecc(struct mtd_info *mtd, int section,
448				      struct mtd_oob_region *oobregion)
449{
450	if (section > 2)
451		return -ERANGE;
452
453	if (!section) {
454		oobregion->offset = 0;
455		oobregion->length = 5;
456	} else if (section == 1) {
457		oobregion->offset = 6;
458		oobregion->length = 2;
459	} else {
460		oobregion->offset = 13;
461		oobregion->length = 3;
462	}
463
464	return 0;
465}
466
467static int hwecc4_ooblayout_small_free(struct mtd_info *mtd, int section,
468				       struct mtd_oob_region *oobregion)
469{
470	if (section > 1)
471		return -ERANGE;
472
473	if (!section) {
474		oobregion->offset = 8;
475		oobregion->length = 5;
476	} else {
477		oobregion->offset = 16;
478		oobregion->length = mtd->oobsize - 16;
479	}
480
481	return 0;
482}
483
484static const struct mtd_ooblayout_ops hwecc4_small_ooblayout_ops = {
485	.ecc = hwecc4_ooblayout_small_ecc,
486	.free = hwecc4_ooblayout_small_free,
487};
488
489#if defined(CONFIG_OF)
490static const struct of_device_id davinci_nand_of_match[] = {
491	{.compatible = "ti,davinci-nand", },
492	{.compatible = "ti,keystone-nand", },
493	{},
494};
495MODULE_DEVICE_TABLE(of, davinci_nand_of_match);
496
497static struct davinci_nand_pdata
498	*nand_davinci_get_pdata(struct platform_device *pdev)
499{
500	if (!dev_get_platdata(&pdev->dev) && pdev->dev.of_node) {
501		struct davinci_nand_pdata *pdata;
502		const char *mode;
503		u32 prop;
504
505		pdata =  devm_kzalloc(&pdev->dev,
506				sizeof(struct davinci_nand_pdata),
507				GFP_KERNEL);
508		pdev->dev.platform_data = pdata;
509		if (!pdata)
510			return ERR_PTR(-ENOMEM);
511		if (!of_property_read_u32(pdev->dev.of_node,
512			"ti,davinci-chipselect", &prop))
513			pdata->core_chipsel = prop;
514		else
515			return ERR_PTR(-EINVAL);
516
517		if (!of_property_read_u32(pdev->dev.of_node,
518			"ti,davinci-mask-ale", &prop))
519			pdata->mask_ale = prop;
520		if (!of_property_read_u32(pdev->dev.of_node,
521			"ti,davinci-mask-cle", &prop))
522			pdata->mask_cle = prop;
523		if (!of_property_read_u32(pdev->dev.of_node,
524			"ti,davinci-mask-chipsel", &prop))
525			pdata->mask_chipsel = prop;
526		if (!of_property_read_string(pdev->dev.of_node,
527			"ti,davinci-ecc-mode", &mode)) {
528			if (!strncmp("none", mode, 4))
529				pdata->engine_type = NAND_ECC_ENGINE_TYPE_NONE;
530			if (!strncmp("soft", mode, 4))
531				pdata->engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
532			if (!strncmp("hw", mode, 2))
533				pdata->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
534		}
535		if (!of_property_read_u32(pdev->dev.of_node,
536			"ti,davinci-ecc-bits", &prop))
537			pdata->ecc_bits = prop;
538
539		if (!of_property_read_u32(pdev->dev.of_node,
540			"ti,davinci-nand-buswidth", &prop) && prop == 16)
541			pdata->options |= NAND_BUSWIDTH_16;
542
543		if (of_property_read_bool(pdev->dev.of_node,
544			"ti,davinci-nand-use-bbt"))
545			pdata->bbt_options = NAND_BBT_USE_FLASH;
546
547		/*
548		 * Since kernel v4.8, this driver has been fixed to enable
549		 * use of 4-bit hardware ECC with subpages and verified on
550		 * TI's keystone EVMs (K2L, K2HK and K2E).
551		 * However, in the interest of not breaking systems using
552		 * existing UBI partitions, sub-page writes are not being
553		 * (re)enabled. If you want to use subpage writes on Keystone
554		 * platforms (i.e. do not have any existing UBI partitions),
555		 * then use "ti,davinci-nand" as the compatible in your
556		 * device-tree file.
557		 */
558		if (of_device_is_compatible(pdev->dev.of_node,
559					    "ti,keystone-nand")) {
560			pdata->options |= NAND_NO_SUBPAGE_WRITE;
561		}
562	}
563
564	return dev_get_platdata(&pdev->dev);
565}
566#else
567static struct davinci_nand_pdata
568	*nand_davinci_get_pdata(struct platform_device *pdev)
569{
570	return dev_get_platdata(&pdev->dev);
571}
572#endif
573
574static int davinci_nand_attach_chip(struct nand_chip *chip)
575{
576	struct mtd_info *mtd = nand_to_mtd(chip);
577	struct davinci_nand_info *info = to_davinci_nand(mtd);
578	struct davinci_nand_pdata *pdata = nand_davinci_get_pdata(info->pdev);
579	int ret = 0;
580
581	if (IS_ERR(pdata))
582		return PTR_ERR(pdata);
583
584	/* Use board-specific ECC config */
585	info->chip.ecc.engine_type = pdata->engine_type;
586	info->chip.ecc.placement = pdata->ecc_placement;
587
588	switch (info->chip.ecc.engine_type) {
589	case NAND_ECC_ENGINE_TYPE_NONE:
590		pdata->ecc_bits = 0;
591		break;
592	case NAND_ECC_ENGINE_TYPE_SOFT:
593		pdata->ecc_bits = 0;
594		/*
595		 * This driver expects Hamming based ECC when engine_type is set
596		 * to NAND_ECC_ENGINE_TYPE_SOFT. Force ecc.algo to
597		 * NAND_ECC_ALGO_HAMMING to avoid adding an extra ->ecc_algo
598		 * field to davinci_nand_pdata.
599		 */
600		info->chip.ecc.algo = NAND_ECC_ALGO_HAMMING;
601		break;
602	case NAND_ECC_ENGINE_TYPE_ON_HOST:
603		if (pdata->ecc_bits == 4) {
604			int chunks = mtd->writesize / 512;
605
606			if (!chunks || mtd->oobsize < 16) {
607				dev_dbg(&info->pdev->dev, "too small\n");
608				return -EINVAL;
609			}
610
611			/*
612			 * No sanity checks:  CPUs must support this,
613			 * and the chips may not use NAND_BUSWIDTH_16.
614			 */
615
616			/* No sharing 4-bit hardware between chipselects yet */
617			spin_lock_irq(&davinci_nand_lock);
618			if (ecc4_busy)
619				ret = -EBUSY;
620			else
621				ecc4_busy = true;
622			spin_unlock_irq(&davinci_nand_lock);
623
624			if (ret == -EBUSY)
625				return ret;
626
627			info->chip.ecc.calculate = nand_davinci_calculate_4bit;
628			info->chip.ecc.correct = nand_davinci_correct_4bit;
629			info->chip.ecc.hwctl = nand_davinci_hwctl_4bit;
630			info->chip.ecc.bytes = 10;
631			info->chip.ecc.options = NAND_ECC_GENERIC_ERASED_CHECK;
632			info->chip.ecc.algo = NAND_ECC_ALGO_BCH;
633
634			/*
635			 * Update ECC layout if needed ... for 1-bit HW ECC, the
636			 * default is OK, but it allocates 6 bytes when only 3
637			 * are needed (for each 512 bytes). For 4-bit HW ECC,
638			 * the default is not usable: 10 bytes needed, not 6.
639			 *
640			 * For small page chips, preserve the manufacturer's
641			 * badblock marking data ... and make sure a flash BBT
642			 * table marker fits in the free bytes.
643			 */
644			if (chunks == 1) {
645				mtd_set_ooblayout(mtd,
646						  &hwecc4_small_ooblayout_ops);
647			} else if (chunks == 4 || chunks == 8) {
648				mtd_set_ooblayout(mtd,
649						  nand_get_large_page_ooblayout());
650				info->chip.ecc.read_page = nand_davinci_read_page_hwecc_oob_first;
651			} else {
652				return -EIO;
653			}
654		} else {
655			/* 1bit ecc hamming */
656			info->chip.ecc.calculate = nand_davinci_calculate_1bit;
657			info->chip.ecc.correct = nand_davinci_correct_1bit;
658			info->chip.ecc.hwctl = nand_davinci_hwctl_1bit;
659			info->chip.ecc.bytes = 3;
660			info->chip.ecc.algo = NAND_ECC_ALGO_HAMMING;
661		}
662		info->chip.ecc.size = 512;
663		info->chip.ecc.strength = pdata->ecc_bits;
664		break;
665	default:
666		return -EINVAL;
667	}
668
669	return ret;
670}
671
672static void nand_davinci_data_in(struct davinci_nand_info *info, void *buf,
673				 unsigned int len, bool force_8bit)
674{
675	u32 alignment = ((uintptr_t)buf | len) & 3;
676
677	if (force_8bit || (alignment & 1))
678		ioread8_rep(info->current_cs, buf, len);
679	else if (alignment & 3)
680		ioread16_rep(info->current_cs, buf, len >> 1);
681	else
682		ioread32_rep(info->current_cs, buf, len >> 2);
683}
684
685static void nand_davinci_data_out(struct davinci_nand_info *info,
686				  const void *buf, unsigned int len,
687				  bool force_8bit)
688{
689	u32 alignment = ((uintptr_t)buf | len) & 3;
690
691	if (force_8bit || (alignment & 1))
692		iowrite8_rep(info->current_cs, buf, len);
693	else if (alignment & 3)
694		iowrite16_rep(info->current_cs, buf, len >> 1);
695	else
696		iowrite32_rep(info->current_cs, buf, len >> 2);
697}
698
699static int davinci_nand_exec_instr(struct davinci_nand_info *info,
700				   const struct nand_op_instr *instr)
701{
702	unsigned int i, timeout_us;
703	u32 status;
704	int ret;
705
706	switch (instr->type) {
707	case NAND_OP_CMD_INSTR:
708		iowrite8(instr->ctx.cmd.opcode,
709			 info->current_cs + info->mask_cle);
710		break;
711
712	case NAND_OP_ADDR_INSTR:
713		for (i = 0; i < instr->ctx.addr.naddrs; i++) {
714			iowrite8(instr->ctx.addr.addrs[i],
715				 info->current_cs + info->mask_ale);
716		}
717		break;
718
719	case NAND_OP_DATA_IN_INSTR:
720		nand_davinci_data_in(info, instr->ctx.data.buf.in,
721				     instr->ctx.data.len,
722				     instr->ctx.data.force_8bit);
723		break;
724
725	case NAND_OP_DATA_OUT_INSTR:
726		nand_davinci_data_out(info, instr->ctx.data.buf.out,
727				      instr->ctx.data.len,
728				      instr->ctx.data.force_8bit);
729		break;
730
731	case NAND_OP_WAITRDY_INSTR:
732		timeout_us = instr->ctx.waitrdy.timeout_ms * 1000;
733		ret = readl_relaxed_poll_timeout(info->base + NANDFSR_OFFSET,
734						 status, status & BIT(0), 100,
735						 timeout_us);
736		if (ret)
737			return ret;
738
739		break;
740	}
741
742	if (instr->delay_ns)
743		ndelay(instr->delay_ns);
744
745	return 0;
746}
747
748static int davinci_nand_exec_op(struct nand_chip *chip,
749				const struct nand_operation *op,
750				bool check_only)
751{
752	struct davinci_nand_info *info = to_davinci_nand(nand_to_mtd(chip));
753	unsigned int i;
754
755	if (check_only)
756		return 0;
757
758	info->current_cs = info->vaddr + (op->cs * info->mask_chipsel);
759
760	for (i = 0; i < op->ninstrs; i++) {
761		int ret;
762
763		ret = davinci_nand_exec_instr(info, &op->instrs[i]);
764		if (ret)
765			return ret;
766	}
767
768	return 0;
769}
770
771static const struct nand_controller_ops davinci_nand_controller_ops = {
772	.attach_chip = davinci_nand_attach_chip,
773	.exec_op = davinci_nand_exec_op,
774};
775
776static int nand_davinci_probe(struct platform_device *pdev)
777{
778	struct davinci_nand_pdata	*pdata;
779	struct davinci_nand_info	*info;
780	struct resource			*res1;
781	struct resource			*res2;
782	void __iomem			*vaddr;
783	void __iomem			*base;
784	int				ret;
785	uint32_t			val;
786	struct mtd_info			*mtd;
787
788	pdata = nand_davinci_get_pdata(pdev);
789	if (IS_ERR(pdata))
790		return PTR_ERR(pdata);
791
792	/* insist on board-specific configuration */
793	if (!pdata)
794		return -ENODEV;
795
796	/* which external chipselect will we be managing? */
797	if (pdata->core_chipsel < 0 || pdata->core_chipsel > 3)
798		return -ENODEV;
799
800	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
801	if (!info)
802		return -ENOMEM;
803
804	platform_set_drvdata(pdev, info);
805
806	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
807	res2 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
808	if (!res1 || !res2) {
809		dev_err(&pdev->dev, "resource missing\n");
810		return -EINVAL;
811	}
812
813	vaddr = devm_ioremap_resource(&pdev->dev, res1);
814	if (IS_ERR(vaddr))
815		return PTR_ERR(vaddr);
816
817	/*
818	 * This registers range is used to setup NAND settings. In case with
819	 * TI AEMIF driver, the same memory address range is requested already
820	 * by AEMIF, so we cannot request it twice, just ioremap.
821	 * The AEMIF and NAND drivers not use the same registers in this range.
822	 */
823	base = devm_ioremap(&pdev->dev, res2->start, resource_size(res2));
824	if (!base) {
825		dev_err(&pdev->dev, "ioremap failed for resource %pR\n", res2);
826		return -EADDRNOTAVAIL;
827	}
828
829	info->pdev		= pdev;
830	info->base		= base;
831	info->vaddr		= vaddr;
832
833	mtd			= nand_to_mtd(&info->chip);
834	mtd->dev.parent		= &pdev->dev;
835	nand_set_flash_node(&info->chip, pdev->dev.of_node);
836
837	/* options such as NAND_BBT_USE_FLASH */
838	info->chip.bbt_options	= pdata->bbt_options;
839	/* options such as 16-bit widths */
840	info->chip.options	= pdata->options;
841	info->chip.bbt_td	= pdata->bbt_td;
842	info->chip.bbt_md	= pdata->bbt_md;
843	info->timing		= pdata->timing;
844
845	info->current_cs	= info->vaddr;
846	info->core_chipsel	= pdata->core_chipsel;
847	info->mask_chipsel	= pdata->mask_chipsel;
848
849	/* use nandboot-capable ALE/CLE masks by default */
850	info->mask_ale		= pdata->mask_ale ? : MASK_ALE;
851	info->mask_cle		= pdata->mask_cle ? : MASK_CLE;
852
853	spin_lock_irq(&davinci_nand_lock);
854
855	/* put CSxNAND into NAND mode */
856	val = davinci_nand_readl(info, NANDFCR_OFFSET);
857	val |= BIT(info->core_chipsel);
858	davinci_nand_writel(info, NANDFCR_OFFSET, val);
859
860	spin_unlock_irq(&davinci_nand_lock);
861
862	/* Scan to find existence of the device(s) */
863	nand_controller_init(&info->controller);
864	info->controller.ops = &davinci_nand_controller_ops;
865	info->chip.controller = &info->controller;
866	ret = nand_scan(&info->chip, pdata->mask_chipsel ? 2 : 1);
867	if (ret < 0) {
868		dev_dbg(&pdev->dev, "no NAND chip(s) found\n");
869		return ret;
870	}
871
872	if (pdata->parts)
873		ret = mtd_device_register(mtd, pdata->parts, pdata->nr_parts);
874	else
875		ret = mtd_device_register(mtd, NULL, 0);
876	if (ret < 0)
877		goto err_cleanup_nand;
878
879	val = davinci_nand_readl(info, NRCSR_OFFSET);
880	dev_info(&pdev->dev, "controller rev. %d.%d\n",
881	       (val >> 8) & 0xff, val & 0xff);
882
883	return 0;
884
885err_cleanup_nand:
886	nand_cleanup(&info->chip);
887
888	return ret;
889}
890
891static int nand_davinci_remove(struct platform_device *pdev)
892{
893	struct davinci_nand_info *info = platform_get_drvdata(pdev);
894	struct nand_chip *chip = &info->chip;
895	int ret;
896
897	spin_lock_irq(&davinci_nand_lock);
898	if (info->chip.ecc.placement == NAND_ECC_PLACEMENT_INTERLEAVED)
899		ecc4_busy = false;
900	spin_unlock_irq(&davinci_nand_lock);
901
902	ret = mtd_device_unregister(nand_to_mtd(chip));
903	WARN_ON(ret);
904	nand_cleanup(chip);
905
906	return 0;
907}
908
909static struct platform_driver nand_davinci_driver = {
910	.probe		= nand_davinci_probe,
911	.remove		= nand_davinci_remove,
912	.driver		= {
913		.name	= "davinci_nand",
914		.of_match_table = of_match_ptr(davinci_nand_of_match),
915	},
916};
917MODULE_ALIAS("platform:davinci_nand");
918
919module_platform_driver(nand_davinci_driver);
920
921MODULE_LICENSE("GPL");
922MODULE_AUTHOR("Texas Instruments");
923MODULE_DESCRIPTION("Davinci NAND flash driver");
924
925