1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * (C) Copyright 2004-2008 Texas Instruments, <www.ti.com>
4 * Rohit Choraria <rohitkc@ti.com>
5 */
6
7#include <common.h>
8#include <log.h>
9#include <system-constants.h>
10#include <asm/io.h>
11#include <dm.h>
12#include <linux/errno.h>
13
14#ifdef CONFIG_ARCH_OMAP2PLUS
15#include <asm/arch/mem.h>
16#endif
17
18#include <linux/io.h>
19#include <linux/ioport.h>
20#include <linux/mtd/omap_gpmc.h>
21#include <linux/mtd/nand_ecc.h>
22#include <linux/mtd/rawnand.h>
23#include <linux/bch.h>
24#include <linux/compiler.h>
25#include <nand.h>
26
27#include "omap_elm.h"
28
29#ifndef GPMC_MAX_CS
30#define GPMC_MAX_CS	4
31#endif
32
33#define BADBLOCK_MARKER_LENGTH	2
34#define SECTOR_BYTES		512
35#define ECCSIZE0_SHIFT		12
36#define ECCSIZE1_SHIFT		22
37#define ECC1RESULTSIZE		0x1
38#define ECCCLEAR		(0x1 << 8)
39#define ECCRESULTREG1		(0x1 << 0)
40/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
41#define BCH4_BIT_PAD		4
42
43#ifdef CONFIG_BCH
44static u8  bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
45				0x97, 0x79, 0xe5, 0x24, 0xb5};
46#endif
47static uint8_t cs_next;
48
49#if defined(CONFIG_NAND_OMAP_GPMC_WSCFG)
50static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE] =
51	{ CONFIG_NAND_OMAP_GPMC_WSCFG };
52#else
53/* wscfg is preset to zero since its a static variable */
54static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE];
55#endif
56
57/*
58 * Driver configurations
59 */
60struct omap_nand_info {
61	struct bch_control *control;
62	enum omap_ecc ecc_scheme;
63	uint8_t cs;
64	uint8_t ws;		/* wait status pin (0,1) */
65	void __iomem *fifo;
66};
67
68/* We are wasting a bit of memory but al least we are safe */
69static struct omap_nand_info omap_nand_info[GPMC_MAX_CS];
70
71/*
72 * omap_nand_hwcontrol - Set the address pointers corretly for the
73 *			following address/data/command operation
74 */
75static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd,
76				uint32_t ctrl)
77{
78	register struct nand_chip *this = mtd_to_nand(mtd);
79	struct omap_nand_info *info = nand_get_controller_data(this);
80	int cs = info->cs;
81
82	/*
83	 * Point the IO_ADDR to DATA and ADDRESS registers instead
84	 * of chip address
85	 */
86	switch (ctrl) {
87	case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
88		this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
89		break;
90	case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
91		this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_adr;
92		break;
93	case NAND_CTRL_CHANGE | NAND_NCE:
94		this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
95		break;
96	}
97
98	if (cmd != NAND_CMD_NONE)
99		writeb(cmd, this->IO_ADDR_W);
100}
101
102/* Check wait pin as dev ready indicator */
103static int omap_dev_ready(struct mtd_info *mtd)
104{
105	register struct nand_chip *this = mtd_to_nand(mtd);
106	struct omap_nand_info *info = nand_get_controller_data(this);
107	return gpmc_cfg->status & (1 << (8 + info->ws));
108}
109
110/*
111 * gen_true_ecc - This function will generate true ECC value, which
112 * can be used when correcting data read from NAND flash memory core
113 *
114 * @ecc_buf:	buffer to store ecc code
115 *
116 * @return:	re-formatted ECC value
117 */
118static uint32_t gen_true_ecc(uint8_t *ecc_buf)
119{
120	return ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) |
121		((ecc_buf[2] & 0x0F) << 8);
122}
123
124/*
125 * omap_correct_data - Compares the ecc read from nand spare area with ECC
126 * registers values and corrects one bit error if it has occurred
127 * Further details can be had from OMAP TRM and the following selected links:
128 * http://en.wikipedia.org/wiki/Hamming_code
129 * http://www.cs.utexas.edu/users/plaxton/c/337/05f/slides/ErrorCorrection-4.pdf
130 *
131 * @mtd:		 MTD device structure
132 * @dat:		 page data
133 * @read_ecc:		 ecc read from nand flash
134 * @calc_ecc:		 ecc read from ECC registers
135 *
136 * Return: 0 if data is OK or corrected, else returns -1
137 */
138static int __maybe_unused omap_correct_data(struct mtd_info *mtd, uint8_t *dat,
139				uint8_t *read_ecc, uint8_t *calc_ecc)
140{
141	uint32_t orig_ecc, new_ecc, res, hm;
142	uint16_t parity_bits, byte;
143	uint8_t bit;
144
145	/* Regenerate the orginal ECC */
146	orig_ecc = gen_true_ecc(read_ecc);
147	new_ecc = gen_true_ecc(calc_ecc);
148	/* Get the XOR of real ecc */
149	res = orig_ecc ^ new_ecc;
150	if (res) {
151		/* Get the hamming width */
152		hm = hweight32(res);
153		/* Single bit errors can be corrected! */
154		if (hm == 12) {
155			/* Correctable data! */
156			parity_bits = res >> 16;
157			bit = (parity_bits & 0x7);
158			byte = (parity_bits >> 3) & 0x1FF;
159			/* Flip the bit to correct */
160			dat[byte] ^= (0x1 << bit);
161		} else if (hm == 1) {
162			printf("Error: Ecc is wrong\n");
163			/* ECC itself is corrupted */
164			return 2;
165		} else {
166			/*
167			 * hm distance != parity pairs OR one, could mean 2 bit
168			 * error OR potentially be on a blank page..
169			 * orig_ecc: contains spare area data from nand flash.
170			 * new_ecc: generated ecc while reading data area.
171			 * Note: if the ecc = 0, all data bits from which it was
172			 * generated are 0xFF.
173			 * The 3 byte(24 bits) ecc is generated per 512byte
174			 * chunk of a page. If orig_ecc(from spare area)
175			 * is 0xFF && new_ecc(computed now from data area)=0x0,
176			 * this means that data area is 0xFF and spare area is
177			 * 0xFF. A sure sign of a erased page!
178			 */
179			if ((orig_ecc == 0x0FFF0FFF) && (new_ecc == 0x00000000))
180				return 0;
181			printf("Error: Bad compare! failed\n");
182			/* detected 2 bit error */
183			return -EBADMSG;
184		}
185	}
186	return 0;
187}
188
189/*
190 * omap_enable_hwecc - configures GPMC as per ECC scheme before read/write
191 * @mtd:	MTD device structure
192 * @mode:	Read/Write mode
193 */
194__maybe_unused
195static void omap_enable_hwecc(struct mtd_info *mtd, int32_t mode)
196{
197	struct nand_chip *nand = mtd_to_nand(mtd);
198	struct omap_nand_info *info = nand_get_controller_data(nand);
199	unsigned int dev_width = (nand->options & NAND_BUSWIDTH_16) ? 1 : 0;
200	u32 val;
201
202	/* Clear ecc and enable bits */
203	writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
204
205	/* program ecc and result sizes */
206	val = ((((nand->ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
207			ECC1RESULTSIZE);
208	writel(val, &gpmc_cfg->ecc_size_config);
209
210	switch (mode) {
211	case NAND_ECC_READ:
212	case NAND_ECC_WRITE:
213		writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
214		break;
215	case NAND_ECC_READSYN:
216		writel(ECCCLEAR, &gpmc_cfg->ecc_control);
217		break;
218	default:
219		printf("%s: error: unrecognized Mode[%d]!\n", __func__, mode);
220		break;
221	}
222
223	/* (ECC 16 or 8 bit col) | ( CS  )  | ECC Enable */
224	val = (dev_width << 7) | (info->cs << 1) | (0x1);
225	writel(val, &gpmc_cfg->ecc_config);
226}
227
228/*
229 *  omap_calculate_ecc - Read ECC result
230 *  @mtd:	MTD structure
231 *  @dat:	unused
232 *  @ecc_code:	ecc_code buffer
233 *  Using noninverted ECC can be considered ugly since writing a blank
234 *  page ie. padding will clear the ECC bytes. This is no problem as
235 *  long nobody is trying to write data on the seemingly unused page.
236 *  Reading an erased page will produce an ECC mismatch between
237 *  generated and read ECC bytes that has to be dealt with separately.
238 *  E.g. if page is 0xFF (fresh erased), and if HW ECC engine within GPMC
239 *  is used, the result of read will be 0x0 while the ECC offsets of the
240 *  spare area will be 0xFF which will result in an ECC mismatch.
241 */
242static int omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat,
243				uint8_t *ecc_code)
244{
245	u32 val;
246
247	val = readl(&gpmc_cfg->ecc1_result);
248	ecc_code[0] = val & 0xFF;
249	ecc_code[1] = (val >> 16) & 0xFF;
250	ecc_code[2] = ((val >> 8) & 0x0F) | ((val >> 20) & 0xF0);
251
252	return 0;
253}
254
255/* GPMC ecc engine settings for read */
256#define BCH_WRAPMODE_1          1       /* BCH wrap mode 1 */
257#define BCH8R_ECC_SIZE0         0x1a    /* ecc_size0 = 26 */
258#define BCH8R_ECC_SIZE1         0x2     /* ecc_size1 = 2 */
259#define BCH4R_ECC_SIZE0         0xd     /* ecc_size0 = 13 */
260#define BCH4R_ECC_SIZE1         0x3     /* ecc_size1 = 3 */
261
262/* GPMC ecc engine settings for write */
263#define BCH_WRAPMODE_6          6       /* BCH wrap mode 6 */
264#define BCH_ECC_SIZE0           0x0     /* ecc_size0 = 0, no oob protection */
265#define BCH_ECC_SIZE1           0x20    /* ecc_size1 = 32 */
266
267/**
268 * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
269 * @mtd: MTD device structure
270 * @mode: Read/Write mode
271 *
272 * When using BCH with SW correction (i.e. no ELM), sector size is set
273 * to 512 bytes and we use BCH_WRAPMODE_6 wrapping mode
274 * for both reading and writing with:
275 * eccsize0 = 0  (no additional protected byte in spare area)
276 * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
277 */
278static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd,
279						 int mode)
280{
281	unsigned int bch_type;
282	unsigned int dev_width, nsectors;
283	struct nand_chip *chip = mtd_to_nand(mtd);
284	struct omap_nand_info *info = nand_get_controller_data(chip);
285	u32 val, wr_mode;
286	unsigned int ecc_size1, ecc_size0;
287
288	/* GPMC configurations for calculating ECC */
289	switch (info->ecc_scheme) {
290	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
291		bch_type = 1;
292		nsectors = 1;
293		wr_mode   = BCH_WRAPMODE_6;
294		ecc_size0 = BCH_ECC_SIZE0;
295		ecc_size1 = BCH_ECC_SIZE1;
296		break;
297	case OMAP_ECC_BCH8_CODE_HW:
298		bch_type = 1;
299		nsectors = 1;
300		if (mode == NAND_ECC_READ) {
301			wr_mode   = BCH_WRAPMODE_1;
302			ecc_size0 = BCH8R_ECC_SIZE0;
303			ecc_size1 = BCH8R_ECC_SIZE1;
304		} else {
305			wr_mode   = BCH_WRAPMODE_6;
306			ecc_size0 = BCH_ECC_SIZE0;
307			ecc_size1 = BCH_ECC_SIZE1;
308		}
309		break;
310	case OMAP_ECC_BCH16_CODE_HW:
311		bch_type = 0x2;
312		nsectors = 1;
313		if (mode == NAND_ECC_READ) {
314			wr_mode   = 0x01;
315			ecc_size0 = 52; /* ECC bits in nibbles per sector */
316			ecc_size1 = 0;  /* non-ECC bits in nibbles per sector */
317		} else {
318			wr_mode   = 0x01;
319			ecc_size0 = 0;  /* extra bits in nibbles per sector */
320			ecc_size1 = 52; /* OOB bits in nibbles per sector */
321		}
322		break;
323	default:
324		return;
325	}
326
327	writel(ECCRESULTREG1, &gpmc_cfg->ecc_control);
328
329	/* Configure ecc size for BCH */
330	val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
331	writel(val, &gpmc_cfg->ecc_size_config);
332
333	dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
334
335	/* BCH configuration */
336	val = ((1			<< 16) | /* enable BCH */
337	       (bch_type		<< 12) | /* BCH4/BCH8/BCH16 */
338	       (wr_mode			<<  8) | /* wrap mode */
339	       (dev_width		<<  7) | /* bus width */
340	       (((nsectors - 1) & 0x7)	<<  4) | /* number of sectors */
341	       (info->cs		<<  1) | /* ECC CS */
342	       (0x1));				 /* enable ECC */
343
344	writel(val, &gpmc_cfg->ecc_config);
345
346	/* Clear ecc and enable bits */
347	writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
348}
349
350/**
351 * omap_calculate_ecc_bch - Generate BCH ECC bytes for one sector
352 * @mtd:        MTD device structure
353 * @dat:        The pointer to data on which ecc is computed
354 * @ecc_code:   The ecc_code buffer
355 *
356 * Support calculating of BCH4/8/16 ECC vectors for one sector
357 * within a page. Sector number is in @sector.
358 */
359static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, const u8 *dat,
360						 u8 *ecc_code)
361{
362	struct nand_chip *chip = mtd_to_nand(mtd);
363	struct omap_nand_info *info = nand_get_controller_data(chip);
364	const uint32_t *ptr;
365	uint32_t val = 0;
366	int8_t i = 0, j;
367
368	switch (info->ecc_scheme) {
369#ifdef CONFIG_BCH
370	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
371#endif
372	case OMAP_ECC_BCH8_CODE_HW:
373		ptr = &gpmc_cfg->bch_result_0_3[0].bch_result_x[3];
374		val = readl(ptr);
375		ecc_code[i++] = (val >>  0) & 0xFF;
376		ptr--;
377		for (j = 0; j < 3; j++) {
378			val = readl(ptr);
379			ecc_code[i++] = (val >> 24) & 0xFF;
380			ecc_code[i++] = (val >> 16) & 0xFF;
381			ecc_code[i++] = (val >>  8) & 0xFF;
382			ecc_code[i++] = (val >>  0) & 0xFF;
383			ptr--;
384		}
385
386		break;
387	case OMAP_ECC_BCH16_CODE_HW:
388		val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[2]);
389		ecc_code[i++] = (val >>  8) & 0xFF;
390		ecc_code[i++] = (val >>  0) & 0xFF;
391		val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[1]);
392		ecc_code[i++] = (val >> 24) & 0xFF;
393		ecc_code[i++] = (val >> 16) & 0xFF;
394		ecc_code[i++] = (val >>  8) & 0xFF;
395		ecc_code[i++] = (val >>  0) & 0xFF;
396		val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[0]);
397		ecc_code[i++] = (val >> 24) & 0xFF;
398		ecc_code[i++] = (val >> 16) & 0xFF;
399		ecc_code[i++] = (val >>  8) & 0xFF;
400		ecc_code[i++] = (val >>  0) & 0xFF;
401		for (j = 3; j >= 0; j--) {
402			val = readl(&gpmc_cfg->bch_result_0_3[0].bch_result_x[j]
403									);
404			ecc_code[i++] = (val >> 24) & 0xFF;
405			ecc_code[i++] = (val >> 16) & 0xFF;
406			ecc_code[i++] = (val >>  8) & 0xFF;
407			ecc_code[i++] = (val >>  0) & 0xFF;
408		}
409		break;
410	default:
411		return -EINVAL;
412	}
413	/* ECC scheme specific syndrome customizations */
414	switch (info->ecc_scheme) {
415#ifdef CONFIG_BCH
416	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
417		/* Add constant polynomial to remainder, so that
418		 * ECC of blank pages results in 0x0 on reading back
419		 */
420		for (i = 0; i < chip->ecc.bytes; i++)
421			ecc_code[i] ^= bch8_polynomial[i];
422		break;
423#endif
424	case OMAP_ECC_BCH8_CODE_HW:
425		/* Set 14th ECC byte as 0x0 for ROM compatibility */
426		ecc_code[chip->ecc.bytes - 1] = 0x0;
427		break;
428	case OMAP_ECC_BCH16_CODE_HW:
429		break;
430	default:
431		return -EINVAL;
432	}
433	return 0;
434}
435
436static inline void omap_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
437{
438	struct nand_chip *chip = mtd_to_nand(mtd);
439	struct omap_nand_info *info = nand_get_controller_data(chip);
440	u32 alignment = ((uintptr_t)buf | len) & 3;
441
442	if (alignment & 1)
443		readsb(info->fifo, buf, len);
444	else if (alignment & 3)
445		readsw(info->fifo, buf, len >> 1);
446	else
447		readsl(info->fifo, buf, len >> 2);
448}
449
450#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
451
452#define PREFETCH_CONFIG1_CS_SHIFT	24
453#define PREFETCH_FIFOTHRESHOLD_MAX	0x40
454#define PREFETCH_FIFOTHRESHOLD(val)	((val) << 8)
455#define PREFETCH_STATUS_COUNT(val)	(val & 0x00003fff)
456#define PREFETCH_STATUS_FIFO_CNT(val)	((val >> 24) & 0x7F)
457#define ENABLE_PREFETCH			(1 << 7)
458
459/**
460 * omap_prefetch_enable - configures and starts prefetch transfer
461 * @fifo_th: fifo threshold to be used for read/ write
462 * @count: number of bytes to be transferred
463 * @is_write: prefetch read(0) or write post(1) mode
464 * @cs: chip select to use
465 */
466static int omap_prefetch_enable(int fifo_th, unsigned int count, int is_write, int cs)
467{
468	uint32_t val;
469
470	if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
471		return -EINVAL;
472
473	if (readl(&gpmc_cfg->prefetch_control))
474		return -EBUSY;
475
476	/* Set the amount of bytes to be prefetched */
477	writel(count, &gpmc_cfg->prefetch_config2);
478
479	val = (cs << PREFETCH_CONFIG1_CS_SHIFT) | (is_write & 1) |
480		PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH;
481	writel(val, &gpmc_cfg->prefetch_config1);
482
483	/*  Start the prefetch engine */
484	writel(1, &gpmc_cfg->prefetch_control);
485
486	return 0;
487}
488
489/**
490 * omap_prefetch_reset - disables and stops the prefetch engine
491 */
492static void omap_prefetch_reset(void)
493{
494	writel(0, &gpmc_cfg->prefetch_control);
495	writel(0, &gpmc_cfg->prefetch_config1);
496}
497
498static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int len)
499{
500	int ret;
501	uint32_t cnt;
502	struct omap_nand_info *info = nand_get_controller_data(chip);
503
504	ret = omap_prefetch_enable(PREFETCH_FIFOTHRESHOLD_MAX, len, 0, info->cs);
505	if (ret < 0)
506		return ret;
507
508	do {
509		int i;
510
511		cnt = readl(&gpmc_cfg->prefetch_status);
512		cnt = PREFETCH_STATUS_FIFO_CNT(cnt);
513
514		for (i = 0; i < cnt / 4; i++) {
515			*buf++ = readl(info->fifo);
516			len -= 4;
517		}
518	} while (len);
519
520	omap_prefetch_reset();
521
522	return 0;
523}
524
525static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len)
526{
527	int ret;
528	uintptr_t head, tail;
529	struct nand_chip *chip = mtd_to_nand(mtd);
530
531	/*
532	 * If the destination buffer is unaligned, start with reading
533	 * the overlap byte-wise.
534	 */
535	head = ((uintptr_t)buf) % 4;
536	if (head) {
537		omap_nand_read_buf(mtd, buf, head);
538		buf += head;
539		len -= head;
540	}
541
542	/*
543	 * Only transfer multiples of 4 bytes in a pre-fetched fashion.
544	 * If there's a residue, care for it byte-wise afterwards.
545	 */
546	tail = len % 4;
547
548	ret = __read_prefetch_aligned(chip, (uint32_t *)buf, len - tail);
549	if (ret < 0) {
550		/* fallback in case the prefetch engine is busy */
551		omap_nand_read_buf(mtd, buf, len);
552	} else if (tail) {
553		buf += len - tail;
554		omap_nand_read_buf(mtd, buf, tail);
555	}
556}
557#endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */
558
559#ifdef CONFIG_NAND_OMAP_ELM
560
561/*
562 * omap_reverse_list - re-orders list elements in reverse order [internal]
563 * @list:	pointer to start of list
564 * @length:	length of list
565*/
566static void omap_reverse_list(u8 *list, unsigned int length)
567{
568	unsigned int i, j;
569	unsigned int half_length = length / 2;
570	u8 tmp;
571	for (i = 0, j = length - 1; i < half_length; i++, j--) {
572		tmp = list[i];
573		list[i] = list[j];
574		list[j] = tmp;
575	}
576}
577
578/*
579 * omap_correct_data_bch - Compares the ecc read from nand spare area
580 * with ECC registers values and corrects one bit error if it has occurred
581 *
582 * @mtd:	MTD device structure
583 * @dat:	page data
584 * @read_ecc:	ecc read from nand flash (ignored)
585 * @calc_ecc:	ecc read from ECC registers
586 *
587 * Return: 0 if data is OK or corrected, else returns -1
588 */
589static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
590				uint8_t *read_ecc, uint8_t *calc_ecc)
591{
592	struct nand_chip *chip = mtd_to_nand(mtd);
593	struct omap_nand_info *info = nand_get_controller_data(chip);
594	struct nand_ecc_ctrl *ecc = &chip->ecc;
595	uint32_t error_count = 0, error_max;
596	uint32_t error_loc[ELM_MAX_ERROR_COUNT];
597	enum bch_level bch_type;
598	uint32_t i, ecc_flag = 0;
599	uint8_t count;
600	uint32_t byte_pos, bit_pos;
601	int err = 0;
602
603	/* check calculated ecc */
604	for (i = 0; i < ecc->bytes && !ecc_flag; i++) {
605		if (calc_ecc[i] != 0x00)
606			goto not_ecc_match;
607	}
608	return 0;
609not_ecc_match:
610
611	/* check for whether it's an erased-page */
612	for (i = 0; i < ecc->bytes; i++) {
613		if (read_ecc[i] != 0xff)
614			goto not_erased;
615	}
616	for (i = 0; i < SECTOR_BYTES; i++) {
617		if (dat[i] != 0xff)
618			goto not_erased;
619	}
620	return 0;
621not_erased:
622
623	/*
624	 * Check for whether it's an erased page with a correctable
625	 * number of bitflips. Erased pages have all 1's in the data,
626	 * so we just compute the number of 0 bits in the data and
627	 * see if it's under the correction threshold.
628	 *
629	 * NOTE: The check for a perfect erased page above is faster for
630	 * the more common case, even though it's logically redundant.
631	 */
632	for (i = 0; i < ecc->bytes; i++)
633		error_count += hweight8(~read_ecc[i]);
634
635	for (i = 0; i < SECTOR_BYTES; i++)
636		error_count += hweight8(~dat[i]);
637
638	if (error_count <= ecc->strength) {
639		memset(read_ecc, 0xFF, ecc->bytes);
640		memset(dat, 0xFF, SECTOR_BYTES);
641		debug("nand: %u bit-flip(s) corrected in erased page\n",
642		      error_count);
643		return error_count;
644	}
645
646	/*
647	 * while reading ECC result we read it in big endian.
648	 * Hence while loading to ELM we have rotate to get the right endian.
649	 */
650	switch (info->ecc_scheme) {
651	case OMAP_ECC_BCH8_CODE_HW:
652		bch_type = BCH_8_BIT;
653		omap_reverse_list(calc_ecc, ecc->bytes - 1);
654		break;
655	case OMAP_ECC_BCH16_CODE_HW:
656		bch_type = BCH_16_BIT;
657		omap_reverse_list(calc_ecc, ecc->bytes);
658		break;
659	default:
660		return -EINVAL;
661	}
662	/* use elm module to check for errors */
663	elm_config(bch_type);
664	error_count = 0;
665	err = elm_check_error(calc_ecc, bch_type, &error_count, error_loc);
666	if (err)
667		return err;
668
669	/* correct bch error */
670	for (count = 0; count < error_count; count++) {
671		switch (info->ecc_scheme) {
672		case OMAP_ECC_BCH8_CODE_HW:
673			/* 14th byte in ECC is reserved to match ROM layout */
674			error_max = SECTOR_BYTES + (ecc->bytes - 1);
675			break;
676		case OMAP_ECC_BCH16_CODE_HW:
677			error_max = SECTOR_BYTES + ecc->bytes;
678			break;
679		default:
680			return -EINVAL;
681		}
682		byte_pos = error_max - (error_loc[count] / 8) - 1;
683		bit_pos  = error_loc[count] % 8;
684		if (byte_pos < SECTOR_BYTES) {
685			dat[byte_pos] ^= 1 << bit_pos;
686			debug("nand: bit-flip corrected @data=%d\n", byte_pos);
687		} else if (byte_pos < error_max) {
688			read_ecc[byte_pos - SECTOR_BYTES] ^= 1 << bit_pos;
689			debug("nand: bit-flip corrected @oob=%d\n", byte_pos -
690								SECTOR_BYTES);
691		} else {
692			err = -EBADMSG;
693			printf("nand: error: invalid bit-flip location\n");
694		}
695	}
696	return (err) ? err : error_count;
697}
698
699/**
700 * omap_read_page_bch - hardware ecc based page read function
701 * @mtd:	mtd info structure
702 * @chip:	nand chip info structure
703 * @buf:	buffer to store read data
704 * @oob_required: caller expects OOB data read to chip->oob_poi
705 * @page:	page number to read
706 *
707 */
708static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
709				uint8_t *buf, int oob_required, int page)
710{
711	int i, eccsize = chip->ecc.size;
712	int eccbytes = chip->ecc.bytes;
713	int eccsteps = chip->ecc.steps;
714	uint8_t *p = buf;
715	uint8_t *ecc_calc = chip->buffers->ecccalc;
716	uint8_t *ecc_code = chip->buffers->ecccode;
717	uint32_t *eccpos = chip->ecc.layout->eccpos;
718	uint8_t *oob = chip->oob_poi;
719	uint32_t oob_pos;
720	u32 data_pos = 0;
721
722	/* oob area start */
723	oob_pos = (eccsize * eccsteps) + chip->ecc.layout->eccpos[0];
724	oob += chip->ecc.layout->eccpos[0];
725
726	for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize,
727	     oob += eccbytes) {
728		/* Enable ECC engine */
729		chip->ecc.hwctl(mtd, NAND_ECC_READ);
730
731		/* read data */
732		chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_pos, -1);
733		chip->read_buf(mtd, p, eccsize);
734
735		/* read respective ecc from oob area */
736		chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
737		chip->read_buf(mtd, oob, eccbytes);
738		/* read syndrome */
739		chip->ecc.calculate(mtd, p, &ecc_calc[i]);
740
741		data_pos += eccsize;
742		oob_pos += eccbytes;
743	}
744
745	for (i = 0; i < chip->ecc.total; i++)
746		ecc_code[i] = chip->oob_poi[eccpos[i]];
747
748	/* error detect & correct */
749	eccsteps = chip->ecc.steps;
750	p = buf;
751
752	for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
753		int stat;
754		stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
755		if (stat < 0)
756			mtd->ecc_stats.failed++;
757		else
758			mtd->ecc_stats.corrected += stat;
759	}
760
761	return 0;
762}
763#endif /* CONFIG_NAND_OMAP_ELM */
764
765/*
766 * OMAP3 BCH8 support (with BCH library)
767 */
768#ifdef CONFIG_BCH
769/**
770 * omap_correct_data_bch_sw - Decode received data and correct errors
771 * @mtd: MTD device structure
772 * @data: page data
773 * @read_ecc: ecc read from nand flash
774 * @calc_ecc: ecc read from HW ECC registers
775 */
776static int omap_correct_data_bch_sw(struct mtd_info *mtd, u_char *data,
777				 u_char *read_ecc, u_char *calc_ecc)
778{
779	int i, count;
780	/* cannot correct more than 8 errors */
781	unsigned int errloc[8];
782	struct nand_chip *chip = mtd_to_nand(mtd);
783	struct omap_nand_info *info = nand_get_controller_data(chip);
784
785	count = decode_bch(info->control, NULL, SECTOR_BYTES,
786				read_ecc, calc_ecc, NULL, errloc);
787	if (count > 0) {
788		/* correct errors */
789		for (i = 0; i < count; i++) {
790			/* correct data only, not ecc bytes */
791			if (errloc[i] < SECTOR_BYTES << 3)
792				data[errloc[i] >> 3] ^= 1 << (errloc[i] & 7);
793			debug("corrected bitflip %u\n", errloc[i]);
794#ifdef DEBUG
795			puts("read_ecc: ");
796			/*
797			 * BCH8 have 13 bytes of ECC; BCH4 needs adoption
798			 * here!
799			 */
800			for (i = 0; i < 13; i++)
801				printf("%02x ", read_ecc[i]);
802			puts("\n");
803			puts("calc_ecc: ");
804			for (i = 0; i < 13; i++)
805				printf("%02x ", calc_ecc[i]);
806			puts("\n");
807#endif
808		}
809	} else if (count < 0) {
810		puts("ecc unrecoverable error\n");
811	}
812	return count;
813}
814
815/**
816 * omap_free_bch - Release BCH ecc resources
817 * @mtd: MTD device structure
818 */
819static void __maybe_unused omap_free_bch(struct mtd_info *mtd)
820{
821	struct nand_chip *chip = mtd_to_nand(mtd);
822	struct omap_nand_info *info = nand_get_controller_data(chip);
823
824	if (info->control) {
825		free_bch(info->control);
826		info->control = NULL;
827	}
828}
829#endif /* CONFIG_BCH */
830
831/**
832 * omap_select_ecc_scheme - configures driver for particular ecc-scheme
833 * @nand: NAND chip device structure
834 * @ecc_scheme: ecc scheme to configure
835 * @pagesize: number of main-area bytes per page of NAND device
836 * @oobsize: number of OOB/spare bytes per page of NAND device
837 */
838static int omap_select_ecc_scheme(struct nand_chip *nand,
839	enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) {
840	struct omap_nand_info	*info		= nand_get_controller_data(nand);
841	struct nand_ecclayout	*ecclayout	= nand->ecc.layout;
842	int eccsteps = pagesize / SECTOR_BYTES;
843	int i;
844
845	switch (ecc_scheme) {
846	case OMAP_ECC_HAM1_CODE_SW:
847		debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n");
848		/* For this ecc-scheme, ecc.bytes, ecc.layout, ... are
849		 * initialized in nand_scan_tail(), so just set ecc.mode */
850		info->control		= NULL;
851		nand->ecc.mode		= NAND_ECC_SOFT;
852		nand->ecc.layout	= NULL;
853		nand->ecc.size		= 0;
854		break;
855
856	case OMAP_ECC_HAM1_CODE_HW:
857		debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n");
858		/* check ecc-scheme requirements before updating ecc info */
859		if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
860			printf("nand: error: insufficient OOB: require=%d\n", (
861				(3 * eccsteps) + BADBLOCK_MARKER_LENGTH));
862			return -EINVAL;
863		}
864		info->control		= NULL;
865		/* populate ecc specific fields */
866		memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
867		nand->ecc.mode		= NAND_ECC_HW;
868		nand->ecc.strength	= 1;
869		nand->ecc.size		= SECTOR_BYTES;
870		nand->ecc.bytes		= 3;
871		nand->ecc.hwctl		= omap_enable_hwecc;
872		nand->ecc.correct	= omap_correct_data;
873		nand->ecc.calculate	= omap_calculate_ecc;
874		/* define ecc-layout */
875		ecclayout->eccbytes	= nand->ecc.bytes * eccsteps;
876		for (i = 0; i < ecclayout->eccbytes; i++) {
877			if (nand->options & NAND_BUSWIDTH_16)
878				ecclayout->eccpos[i] = i + 2;
879			else
880				ecclayout->eccpos[i] = i + 1;
881		}
882		ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
883		ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
884						BADBLOCK_MARKER_LENGTH;
885		break;
886
887	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
888#ifdef CONFIG_BCH
889		debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
890		/* check ecc-scheme requirements before updating ecc info */
891		if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
892			printf("nand: error: insufficient OOB: require=%d\n", (
893				(13 * eccsteps) + BADBLOCK_MARKER_LENGTH));
894			return -EINVAL;
895		}
896		/* check if BCH S/W library can be used for error detection */
897		info->control = init_bch(13, 8, 0x201b);
898		if (!info->control) {
899			printf("nand: error: could not init_bch()\n");
900			return -ENODEV;
901		}
902		/* populate ecc specific fields */
903		memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
904		nand->ecc.mode		= NAND_ECC_HW;
905		nand->ecc.strength	= 8;
906		nand->ecc.size		= SECTOR_BYTES;
907		nand->ecc.bytes		= 13;
908		nand->ecc.hwctl		= omap_enable_hwecc_bch;
909		nand->ecc.correct	= omap_correct_data_bch_sw;
910		nand->ecc.calculate	= omap_calculate_ecc_bch;
911		nand->ecc.steps		= eccsteps;
912		/* define ecc-layout */
913		ecclayout->eccbytes	= nand->ecc.bytes * eccsteps;
914		ecclayout->eccpos[0]	= BADBLOCK_MARKER_LENGTH;
915		for (i = 1; i < ecclayout->eccbytes; i++) {
916			if (i % nand->ecc.bytes)
917				ecclayout->eccpos[i] =
918						ecclayout->eccpos[i - 1] + 1;
919			else
920				ecclayout->eccpos[i] =
921						ecclayout->eccpos[i - 1] + 2;
922		}
923		ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
924		ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
925						BADBLOCK_MARKER_LENGTH;
926		break;
927#else
928		printf("nand: error: CONFIG_BCH required for ECC\n");
929		return -EINVAL;
930#endif
931
932	case OMAP_ECC_BCH8_CODE_HW:
933#ifdef CONFIG_NAND_OMAP_ELM
934		debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n");
935		/* check ecc-scheme requirements before updating ecc info */
936		if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
937			printf("nand: error: insufficient OOB: require=%d\n", (
938				(14 * eccsteps) + BADBLOCK_MARKER_LENGTH));
939			return -EINVAL;
940		}
941		/* intialize ELM for ECC error detection */
942		elm_init();
943		info->control		= NULL;
944		/* populate ecc specific fields */
945		memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
946		nand->ecc.mode		= NAND_ECC_HW;
947		nand->ecc.strength	= 8;
948		nand->ecc.size		= SECTOR_BYTES;
949		nand->ecc.bytes		= 14;
950		nand->ecc.hwctl		= omap_enable_hwecc_bch;
951		nand->ecc.correct	= omap_correct_data_bch;
952		nand->ecc.calculate	= omap_calculate_ecc_bch;
953		nand->ecc.read_page	= omap_read_page_bch;
954		nand->ecc.steps		= eccsteps;
955		/* define ecc-layout */
956		ecclayout->eccbytes	= nand->ecc.bytes * eccsteps;
957		for (i = 0; i < ecclayout->eccbytes; i++)
958			ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
959		ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
960		ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
961						BADBLOCK_MARKER_LENGTH;
962		break;
963#else
964		printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
965		return -EINVAL;
966#endif
967
968	case OMAP_ECC_BCH16_CODE_HW:
969#ifdef CONFIG_NAND_OMAP_ELM
970		debug("nand: using OMAP_ECC_BCH16_CODE_HW\n");
971		/* check ecc-scheme requirements before updating ecc info */
972		if ((26 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
973			printf("nand: error: insufficient OOB: require=%d\n", (
974				(26 * eccsteps) + BADBLOCK_MARKER_LENGTH));
975			return -EINVAL;
976		}
977		/* intialize ELM for ECC error detection */
978		elm_init();
979		/* populate ecc specific fields */
980		nand->ecc.mode		= NAND_ECC_HW;
981		nand->ecc.size		= SECTOR_BYTES;
982		nand->ecc.bytes		= 26;
983		nand->ecc.strength	= 16;
984		nand->ecc.hwctl		= omap_enable_hwecc_bch;
985		nand->ecc.correct	= omap_correct_data_bch;
986		nand->ecc.calculate	= omap_calculate_ecc_bch;
987		nand->ecc.read_page	= omap_read_page_bch;
988		nand->ecc.steps		= eccsteps;
989		/* define ecc-layout */
990		ecclayout->eccbytes	= nand->ecc.bytes * eccsteps;
991		for (i = 0; i < ecclayout->eccbytes; i++)
992			ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
993		ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
994		ecclayout->oobfree[0].length = oobsize - nand->ecc.bytes -
995						BADBLOCK_MARKER_LENGTH;
996		break;
997#else
998		printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
999		return -EINVAL;
1000#endif
1001	default:
1002		debug("nand: error: ecc scheme not enabled or supported\n");
1003		return -EINVAL;
1004	}
1005
1006	/* nand_scan_tail() sets ham1 sw ecc; hw ecc layout is set by driver */
1007	if (ecc_scheme != OMAP_ECC_HAM1_CODE_SW)
1008		nand->ecc.layout = ecclayout;
1009
1010	info->ecc_scheme = ecc_scheme;
1011	return 0;
1012}
1013
1014#ifndef CONFIG_SPL_BUILD
1015/*
1016 * omap_nand_switch_ecc - switch the ECC operation between different engines
1017 * (h/w and s/w) and different algorithms (hamming and BCHx)
1018 *
1019 * @hardware		- true if one of the HW engines should be used
1020 * @eccstrength		- the number of bits that could be corrected
1021 *			  (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16)
1022 */
1023int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
1024{
1025	struct nand_chip *nand;
1026	struct mtd_info *mtd = get_nand_dev_by_index(nand_curr_device);
1027	int err = 0;
1028
1029	if (!mtd) {
1030		printf("nand: error: no NAND devices found\n");
1031		return -ENODEV;
1032	}
1033
1034	nand = mtd_to_nand(mtd);
1035	nand->options |= NAND_OWN_BUFFERS;
1036	nand->options &= ~NAND_SUBPAGE_READ;
1037	/* Setup the ecc configurations again */
1038	if (hardware) {
1039		if (eccstrength == 1) {
1040			err = omap_select_ecc_scheme(nand,
1041					OMAP_ECC_HAM1_CODE_HW,
1042					mtd->writesize, mtd->oobsize);
1043		} else if (eccstrength == 8) {
1044			err = omap_select_ecc_scheme(nand,
1045					OMAP_ECC_BCH8_CODE_HW,
1046					mtd->writesize, mtd->oobsize);
1047		} else if (eccstrength == 16) {
1048			err = omap_select_ecc_scheme(nand,
1049					OMAP_ECC_BCH16_CODE_HW,
1050					mtd->writesize, mtd->oobsize);
1051		} else {
1052			printf("nand: error: unsupported ECC scheme\n");
1053			return -EINVAL;
1054		}
1055	} else {
1056		if (eccstrength == 1) {
1057			err = omap_select_ecc_scheme(nand,
1058					OMAP_ECC_HAM1_CODE_SW,
1059					mtd->writesize, mtd->oobsize);
1060		} else if (eccstrength == 8) {
1061			err = omap_select_ecc_scheme(nand,
1062					OMAP_ECC_BCH8_CODE_HW_DETECTION_SW,
1063					mtd->writesize, mtd->oobsize);
1064		} else {
1065			printf("nand: error: unsupported ECC scheme\n");
1066			return -EINVAL;
1067		}
1068	}
1069
1070	/* Update NAND handling after ECC mode switch */
1071	if (!err)
1072		err = nand_scan_tail(mtd);
1073	return err;
1074}
1075#endif /* CONFIG_SPL_BUILD */
1076
1077/*
1078 * Board-specific NAND initialization. The following members of the
1079 * argument are board-specific:
1080 * - IO_ADDR_R: address to read the 8 I/O lines of the flash device
1081 * - IO_ADDR_W: address to write the 8 I/O lines of the flash device
1082 * - cmd_ctrl: hardwarespecific function for accesing control-lines
1083 * - waitfunc: hardwarespecific function for accesing device ready/busy line
1084 * - ecc.hwctl: function to enable (reset) hardware ecc generator
1085 * - ecc.mode: mode of ecc, see defines
1086 * - chip_delay: chip dependent delay for transfering data from array to
1087 *   read regs (tR)
1088 * - options: various chip options. They can partly be set to inform
1089 *   nand_scan about special functionality. See the defines for further
1090 *   explanation
1091 */
1092int gpmc_nand_init(struct nand_chip *nand, void __iomem *nand_base)
1093{
1094	int32_t gpmc_config = 0;
1095	int cs = cs_next++;
1096	int err = 0;
1097	struct omap_nand_info *info;
1098
1099	/*
1100	 * xloader/Uboot's gpmc configuration would have configured GPMC for
1101	 * nand type of memory. The following logic scans and latches on to the
1102	 * first CS with NAND type memory.
1103	 * TBD: need to make this logic generic to handle multiple CS NAND
1104	 * devices.
1105	 */
1106	while (cs < GPMC_MAX_CS) {
1107		/* Check if NAND type is set */
1108		if ((readl(&gpmc_cfg->cs[cs].config1) & 0xC00) == 0x800) {
1109			/* Found it!! */
1110			break;
1111		}
1112		cs++;
1113	}
1114	if (cs >= GPMC_MAX_CS) {
1115		printf("nand: error: Unable to find NAND settings in "
1116			"GPMC Configuration - quitting\n");
1117		return -ENODEV;
1118	}
1119
1120	gpmc_config = readl(&gpmc_cfg->config);
1121	/* Disable Write protect */
1122	gpmc_config |= 0x10;
1123	writel(gpmc_config, &gpmc_cfg->config);
1124
1125	nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
1126	nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
1127
1128	info = &omap_nand_info[cs];
1129	info->control = NULL;
1130	info->cs = cs;
1131	info->ws = wscfg[cs];
1132	info->fifo = nand_base;
1133	nand_set_controller_data(nand, &omap_nand_info[cs]);
1134	nand->cmd_ctrl	= omap_nand_hwcontrol;
1135	nand->options	|= NAND_NO_PADDING | NAND_CACHEPRG;
1136	nand->chip_delay = 100;
1137	nand->ecc.layout = kzalloc(sizeof(*nand->ecc.layout), GFP_KERNEL);
1138	if (!nand->ecc.layout)
1139		return -ENOMEM;
1140
1141	/* configure driver and controller based on NAND device bus-width */
1142	gpmc_config = readl(&gpmc_cfg->cs[cs].config1);
1143#if defined(CONFIG_SYS_NAND_BUSWIDTH_16BIT)
1144	nand->options |= NAND_BUSWIDTH_16;
1145	writel(gpmc_config | (0x1 << 12), &gpmc_cfg->cs[cs].config1);
1146#else
1147	nand->options &= ~NAND_BUSWIDTH_16;
1148	writel(gpmc_config & ~(0x1 << 12), &gpmc_cfg->cs[cs].config1);
1149#endif
1150	/* select ECC scheme */
1151#if defined(CONFIG_NAND_OMAP_ECCSCHEME)
1152	err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME,
1153			CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
1154#else
1155	/* pagesize and oobsize are not required to configure sw ecc-scheme */
1156	err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
1157			0, 0);
1158#endif
1159	if (err)
1160		return err;
1161
1162#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
1163	nand->read_buf = omap_nand_read_prefetch;
1164#else
1165	nand->read_buf = omap_nand_read_buf;
1166#endif
1167
1168	nand->dev_ready = omap_dev_ready;
1169
1170	return 0;
1171}
1172
1173/* First NAND chip for SPL use only */
1174static __maybe_unused struct nand_chip *nand_chip;
1175
1176#if CONFIG_IS_ENABLED(SYS_NAND_SELF_INIT)
1177
1178static int gpmc_nand_probe(struct udevice *dev)
1179{
1180	struct nand_chip *nand = dev_get_priv(dev);
1181	struct mtd_info *mtd = nand_to_mtd(nand);
1182	struct resource res;
1183	void __iomem *base;
1184	int ret;
1185
1186	ret = dev_read_resource(dev, 0, &res);
1187	if (ret)
1188		return ret;
1189
1190	base = devm_ioremap(dev, res.start, resource_size(&res));
1191	gpmc_nand_init(nand, base);
1192	mtd->dev = dev;
1193	nand_set_flash_node(nand, dev_ofnode(dev));
1194
1195	ret = nand_scan(mtd, CONFIG_SYS_NAND_MAX_CHIPS);
1196	if (ret)
1197		return ret;
1198
1199	ret = nand_register(0, mtd);
1200	if (ret)
1201		return ret;
1202
1203	if (!nand_chip)
1204		nand_chip = nand;
1205
1206	return 0;
1207}
1208
1209static const struct udevice_id gpmc_nand_ids[] = {
1210	{ .compatible = "ti,am64-nand" },
1211	{ .compatible = "ti,omap2-nand" },
1212	{ }
1213};
1214
1215U_BOOT_DRIVER(gpmc_nand) = {
1216	.name           = "gpmc-nand",
1217	.id             = UCLASS_MTD,
1218	.of_match       = gpmc_nand_ids,
1219	.probe          = gpmc_nand_probe,
1220	.priv_auto	= sizeof(struct nand_chip),
1221};
1222
1223void board_nand_init(void)
1224{
1225	struct udevice *dev;
1226	int ret;
1227
1228#ifdef CONFIG_NAND_OMAP_ELM
1229	ret = uclass_get_device_by_driver(UCLASS_MTD,
1230					  DM_DRIVER_GET(gpmc_elm), &dev);
1231	if (ret && ret != -ENODEV) {
1232		pr_err("%s: Failed to get ELM device: %d\n", __func__, ret);
1233		return;
1234	}
1235#endif
1236
1237	ret = uclass_get_device_by_driver(UCLASS_MTD,
1238					  DM_DRIVER_GET(gpmc_nand), &dev);
1239	if (ret && ret != -ENODEV)
1240		pr_err("%s: Failed to get GPMC device: %d\n", __func__, ret);
1241}
1242
1243#else
1244
1245int board_nand_init(struct nand_chip *nand)
1246{
1247	return gpmc_nand_init(nand, (void __iomem *)CFG_SYS_NAND_BASE);
1248}
1249
1250#endif /* CONFIG_SYS_NAND_SELF_INIT */
1251
1252#if defined(CONFIG_SPL_NAND_INIT)
1253
1254/* nand_init() is provided by nand.c */
1255
1256/* Unselect after operation */
1257void nand_deselect(void)
1258{
1259	struct mtd_info *mtd = nand_to_mtd(nand_chip);
1260
1261	if (nand_chip->select_chip)
1262		nand_chip->select_chip(mtd, -1);
1263}
1264
1265static int nand_is_bad_block(int block)
1266{
1267	struct mtd_info *mtd = nand_to_mtd(nand_chip);
1268
1269	loff_t ofs = block * CONFIG_SYS_NAND_BLOCK_SIZE;
1270
1271	return nand_chip->block_bad(mtd, ofs);
1272}
1273
1274static int nand_read_page(int block, int page, uchar *dst)
1275{
1276	int page_addr = block * SYS_NAND_BLOCK_PAGES + page;
1277	loff_t ofs = page_addr * CONFIG_SYS_NAND_PAGE_SIZE;
1278	int ret;
1279	size_t len = CONFIG_SYS_NAND_PAGE_SIZE;
1280	struct mtd_info *mtd = nand_to_mtd(nand_chip);
1281
1282	ret = nand_read(mtd, ofs, &len, dst);
1283	if (ret)
1284		printf("nand_read failed %d\n", ret);
1285
1286	return ret;
1287}
1288
1289#include "nand_spl_loaders.c"
1290#endif /* CONFIG_SPL_NAND_INIT */
1291