1/*
2 *  Copyright �� 2003 Rick Bronson
3 *
4 *  Derived from drivers/mtd/nand/autcpu12.c
5 *	 Copyright �� 2001 Thomas Gleixner (gleixner@autronix.de)
6 *
7 *  Derived from drivers/mtd/spia.c
8 *	 Copyright �� 2000 Steven J. Hill (sjhill@cotw.com)
9 *
10 *
11 *  Add Hardware ECC support for AT91SAM9260 / AT91SAM9263
12 *     Richard Genoud (richard.genoud@gmail.com), Adeneo Copyright �� 2007
13 *
14 *     Derived from Das U-Boot source code
15 *     		(u-boot-1.1.5/board/atmel/at91sam9263ek/nand.c)
16 *     �� Copyright 2006 ATMEL Rousset, Lacressonniere Nicolas
17 *
18 *  Add Programmable Multibit ECC support for various AT91 SoC
19 *     �� Copyright 2012 ATMEL, Hong Xu
20 *
21 *  Add Nand Flash Controller support for SAMA5 SoC
22 *     �� Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
23 *
24 * This program is free software; you can redistribute it and/or modify
25 * it under the terms of the GNU General Public License version 2 as
26 * published by the Free Software Foundation.
27 *
28 */
29
30#include <linux/clk.h>
31#include <linux/dma-mapping.h>
32#include <linux/slab.h>
33#include <linux/module.h>
34#include <linux/moduleparam.h>
35#include <linux/platform_device.h>
36#include <linux/of.h>
37#include <linux/of_device.h>
38#include <linux/of_gpio.h>
39#include <linux/of_mtd.h>
40#include <linux/mtd/mtd.h>
41#include <linux/mtd/nand.h>
42#include <linux/mtd/partitions.h>
43
44#include <linux/delay.h>
45#include <linux/dmaengine.h>
46#include <linux/gpio.h>
47#include <linux/interrupt.h>
48#include <linux/io.h>
49#include <linux/platform_data/atmel.h>
50
51static int use_dma = 1;
52module_param(use_dma, int, 0);
53
54static int on_flash_bbt = 0;
55module_param(on_flash_bbt, int, 0);
56
57/* Register access macros */
58#define ecc_readl(add, reg)				\
59	__raw_readl(add + ATMEL_ECC_##reg)
60#define ecc_writel(add, reg, value)			\
61	__raw_writel((value), add + ATMEL_ECC_##reg)
62
63#include "atmel_nand_ecc.h"	/* Hardware ECC registers */
64#include "atmel_nand_nfc.h"	/* Nand Flash Controller definition */
65
66struct atmel_nand_caps {
67	bool pmecc_correct_erase_page;
68};
69
70/* oob layout for large page size
71 * bad block info is on bytes 0 and 1
72 * the bytes have to be consecutives to avoid
73 * several NAND_CMD_RNDOUT during read
74 */
75static struct nand_ecclayout atmel_oobinfo_large = {
76	.eccbytes = 4,
77	.eccpos = {60, 61, 62, 63},
78	.oobfree = {
79		{2, 58}
80	},
81};
82
83/* oob layout for small page size
84 * bad block info is on bytes 4 and 5
85 * the bytes have to be consecutives to avoid
86 * several NAND_CMD_RNDOUT during read
87 */
88static struct nand_ecclayout atmel_oobinfo_small = {
89	.eccbytes = 4,
90	.eccpos = {0, 1, 2, 3},
91	.oobfree = {
92		{6, 10}
93	},
94};
95
96struct atmel_nfc {
97	void __iomem		*base_cmd_regs;
98	void __iomem		*hsmc_regs;
99	void			*sram_bank0;
100	dma_addr_t		sram_bank0_phys;
101	bool			use_nfc_sram;
102	bool			write_by_sram;
103
104	struct clk		*clk;
105
106	bool			is_initialized;
107	struct completion	comp_ready;
108	struct completion	comp_cmd_done;
109	struct completion	comp_xfer_done;
110
111	/* Point to the sram bank which include readed data via NFC */
112	void			*data_in_sram;
113	bool			will_write_sram;
114};
115static struct atmel_nfc	nand_nfc;
116
117struct atmel_nand_host {
118	struct nand_chip	nand_chip;
119	struct mtd_info		mtd;
120	void __iomem		*io_base;
121	dma_addr_t		io_phys;
122	struct atmel_nand_data	board;
123	struct device		*dev;
124	void __iomem		*ecc;
125
126	struct completion	comp;
127	struct dma_chan		*dma_chan;
128
129	struct atmel_nfc	*nfc;
130
131	struct atmel_nand_caps	*caps;
132	bool			has_pmecc;
133	u8			pmecc_corr_cap;
134	u16			pmecc_sector_size;
135	bool			has_no_lookup_table;
136	u32			pmecc_lookup_table_offset;
137	u32			pmecc_lookup_table_offset_512;
138	u32			pmecc_lookup_table_offset_1024;
139
140	int			pmecc_degree;	/* Degree of remainders */
141	int			pmecc_cw_len;	/* Length of codeword */
142
143	void __iomem		*pmerrloc_base;
144	void __iomem		*pmecc_rom_base;
145
146	/* lookup table for alpha_to and index_of */
147	void __iomem		*pmecc_alpha_to;
148	void __iomem		*pmecc_index_of;
149
150	/* data for pmecc computation */
151	int16_t			*pmecc_partial_syn;
152	int16_t			*pmecc_si;
153	int16_t			*pmecc_smu;	/* Sigma table */
154	int16_t			*pmecc_lmu;	/* polynomal order */
155	int			*pmecc_mu;
156	int			*pmecc_dmu;
157	int			*pmecc_delta;
158};
159
160static struct nand_ecclayout atmel_pmecc_oobinfo;
161
162/*
163 * Enable NAND.
164 */
165static void atmel_nand_enable(struct atmel_nand_host *host)
166{
167	if (gpio_is_valid(host->board.enable_pin))
168		gpio_set_value(host->board.enable_pin, 0);
169}
170
171/*
172 * Disable NAND.
173 */
174static void atmel_nand_disable(struct atmel_nand_host *host)
175{
176	if (gpio_is_valid(host->board.enable_pin))
177		gpio_set_value(host->board.enable_pin, 1);
178}
179
180/*
181 * Hardware specific access to control-lines
182 */
183static void atmel_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
184{
185	struct nand_chip *nand_chip = mtd->priv;
186	struct atmel_nand_host *host = nand_chip->priv;
187
188	if (ctrl & NAND_CTRL_CHANGE) {
189		if (ctrl & NAND_NCE)
190			atmel_nand_enable(host);
191		else
192			atmel_nand_disable(host);
193	}
194	if (cmd == NAND_CMD_NONE)
195		return;
196
197	if (ctrl & NAND_CLE)
198		writeb(cmd, host->io_base + (1 << host->board.cle));
199	else
200		writeb(cmd, host->io_base + (1 << host->board.ale));
201}
202
203/*
204 * Read the Device Ready pin.
205 */
206static int atmel_nand_device_ready(struct mtd_info *mtd)
207{
208	struct nand_chip *nand_chip = mtd->priv;
209	struct atmel_nand_host *host = nand_chip->priv;
210
211	return gpio_get_value(host->board.rdy_pin) ^
212                !!host->board.rdy_pin_active_low;
213}
214
215/* Set up for hardware ready pin and enable pin. */
216static int atmel_nand_set_enable_ready_pins(struct mtd_info *mtd)
217{
218	struct nand_chip *chip = mtd->priv;
219	struct atmel_nand_host *host = chip->priv;
220	int res = 0;
221
222	if (gpio_is_valid(host->board.rdy_pin)) {
223		res = devm_gpio_request(host->dev,
224				host->board.rdy_pin, "nand_rdy");
225		if (res < 0) {
226			dev_err(host->dev,
227				"can't request rdy gpio %d\n",
228				host->board.rdy_pin);
229			return res;
230		}
231
232		res = gpio_direction_input(host->board.rdy_pin);
233		if (res < 0) {
234			dev_err(host->dev,
235				"can't request input direction rdy gpio %d\n",
236				host->board.rdy_pin);
237			return res;
238		}
239
240		chip->dev_ready = atmel_nand_device_ready;
241	}
242
243	if (gpio_is_valid(host->board.enable_pin)) {
244		res = devm_gpio_request(host->dev,
245				host->board.enable_pin, "nand_enable");
246		if (res < 0) {
247			dev_err(host->dev,
248				"can't request enable gpio %d\n",
249				host->board.enable_pin);
250			return res;
251		}
252
253		res = gpio_direction_output(host->board.enable_pin, 1);
254		if (res < 0) {
255			dev_err(host->dev,
256				"can't request output direction enable gpio %d\n",
257				host->board.enable_pin);
258			return res;
259		}
260	}
261
262	return res;
263}
264
265/*
266 * Minimal-overhead PIO for data access.
267 */
268static void atmel_read_buf8(struct mtd_info *mtd, u8 *buf, int len)
269{
270	struct nand_chip	*nand_chip = mtd->priv;
271	struct atmel_nand_host *host = nand_chip->priv;
272
273	if (host->nfc && host->nfc->use_nfc_sram && host->nfc->data_in_sram) {
274		memcpy(buf, host->nfc->data_in_sram, len);
275		host->nfc->data_in_sram += len;
276	} else {
277		__raw_readsb(nand_chip->IO_ADDR_R, buf, len);
278	}
279}
280
281static void atmel_read_buf16(struct mtd_info *mtd, u8 *buf, int len)
282{
283	struct nand_chip	*nand_chip = mtd->priv;
284	struct atmel_nand_host *host = nand_chip->priv;
285
286	if (host->nfc && host->nfc->use_nfc_sram && host->nfc->data_in_sram) {
287		memcpy(buf, host->nfc->data_in_sram, len);
288		host->nfc->data_in_sram += len;
289	} else {
290		__raw_readsw(nand_chip->IO_ADDR_R, buf, len / 2);
291	}
292}
293
294static void atmel_write_buf8(struct mtd_info *mtd, const u8 *buf, int len)
295{
296	struct nand_chip	*nand_chip = mtd->priv;
297
298	__raw_writesb(nand_chip->IO_ADDR_W, buf, len);
299}
300
301static void atmel_write_buf16(struct mtd_info *mtd, const u8 *buf, int len)
302{
303	struct nand_chip	*nand_chip = mtd->priv;
304
305	__raw_writesw(nand_chip->IO_ADDR_W, buf, len / 2);
306}
307
308static void dma_complete_func(void *completion)
309{
310	complete(completion);
311}
312
313static int nfc_set_sram_bank(struct atmel_nand_host *host, unsigned int bank)
314{
315	/* NFC only has two banks. Must be 0 or 1 */
316	if (bank > 1)
317		return -EINVAL;
318
319	if (bank) {
320		/* Only for a 2k-page or lower flash, NFC can handle 2 banks */
321		if (host->mtd.writesize > 2048)
322			return -EINVAL;
323		nfc_writel(host->nfc->hsmc_regs, BANK, ATMEL_HSMC_NFC_BANK1);
324	} else {
325		nfc_writel(host->nfc->hsmc_regs, BANK, ATMEL_HSMC_NFC_BANK0);
326	}
327
328	return 0;
329}
330
331static uint nfc_get_sram_off(struct atmel_nand_host *host)
332{
333	if (nfc_readl(host->nfc->hsmc_regs, BANK) & ATMEL_HSMC_NFC_BANK1)
334		return NFC_SRAM_BANK1_OFFSET;
335	else
336		return 0;
337}
338
339static dma_addr_t nfc_sram_phys(struct atmel_nand_host *host)
340{
341	if (nfc_readl(host->nfc->hsmc_regs, BANK) & ATMEL_HSMC_NFC_BANK1)
342		return host->nfc->sram_bank0_phys + NFC_SRAM_BANK1_OFFSET;
343	else
344		return host->nfc->sram_bank0_phys;
345}
346
347static int atmel_nand_dma_op(struct mtd_info *mtd, void *buf, int len,
348			       int is_read)
349{
350	struct dma_device *dma_dev;
351	enum dma_ctrl_flags flags;
352	dma_addr_t dma_src_addr, dma_dst_addr, phys_addr;
353	struct dma_async_tx_descriptor *tx = NULL;
354	dma_cookie_t cookie;
355	struct nand_chip *chip = mtd->priv;
356	struct atmel_nand_host *host = chip->priv;
357	void *p = buf;
358	int err = -EIO;
359	enum dma_data_direction dir = is_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
360	struct atmel_nfc *nfc = host->nfc;
361
362	if (buf >= high_memory)
363		goto err_buf;
364
365	dma_dev = host->dma_chan->device;
366
367	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
368
369	phys_addr = dma_map_single(dma_dev->dev, p, len, dir);
370	if (dma_mapping_error(dma_dev->dev, phys_addr)) {
371		dev_err(host->dev, "Failed to dma_map_single\n");
372		goto err_buf;
373	}
374
375	if (is_read) {
376		if (nfc && nfc->data_in_sram)
377			dma_src_addr = nfc_sram_phys(host) + (nfc->data_in_sram
378				- (nfc->sram_bank0 + nfc_get_sram_off(host)));
379		else
380			dma_src_addr = host->io_phys;
381
382		dma_dst_addr = phys_addr;
383	} else {
384		dma_src_addr = phys_addr;
385
386		if (nfc && nfc->write_by_sram)
387			dma_dst_addr = nfc_sram_phys(host);
388		else
389			dma_dst_addr = host->io_phys;
390	}
391
392	tx = dma_dev->device_prep_dma_memcpy(host->dma_chan, dma_dst_addr,
393					     dma_src_addr, len, flags);
394	if (!tx) {
395		dev_err(host->dev, "Failed to prepare DMA memcpy\n");
396		goto err_dma;
397	}
398
399	init_completion(&host->comp);
400	tx->callback = dma_complete_func;
401	tx->callback_param = &host->comp;
402
403	cookie = tx->tx_submit(tx);
404	if (dma_submit_error(cookie)) {
405		dev_err(host->dev, "Failed to do DMA tx_submit\n");
406		goto err_dma;
407	}
408
409	dma_async_issue_pending(host->dma_chan);
410	wait_for_completion(&host->comp);
411
412	if (is_read && nfc && nfc->data_in_sram)
413		/* After read data from SRAM, need to increase the position */
414		nfc->data_in_sram += len;
415
416	err = 0;
417
418err_dma:
419	dma_unmap_single(dma_dev->dev, phys_addr, len, dir);
420err_buf:
421	if (err != 0)
422		dev_dbg(host->dev, "Fall back to CPU I/O\n");
423	return err;
424}
425
426static void atmel_read_buf(struct mtd_info *mtd, u8 *buf, int len)
427{
428	struct nand_chip *chip = mtd->priv;
429	struct atmel_nand_host *host = chip->priv;
430
431	if (use_dma && len > mtd->oobsize)
432		/* only use DMA for bigger than oob size: better performances */
433		if (atmel_nand_dma_op(mtd, buf, len, 1) == 0)
434			return;
435
436	if (host->board.bus_width_16)
437		atmel_read_buf16(mtd, buf, len);
438	else
439		atmel_read_buf8(mtd, buf, len);
440}
441
442static void atmel_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
443{
444	struct nand_chip *chip = mtd->priv;
445	struct atmel_nand_host *host = chip->priv;
446
447	if (use_dma && len > mtd->oobsize)
448		/* only use DMA for bigger than oob size: better performances */
449		if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) == 0)
450			return;
451
452	if (host->board.bus_width_16)
453		atmel_write_buf16(mtd, buf, len);
454	else
455		atmel_write_buf8(mtd, buf, len);
456}
457
458/*
459 * Return number of ecc bytes per sector according to sector size and
460 * correction capability
461 *
462 * Following table shows what at91 PMECC supported:
463 * Correction Capability	Sector_512_bytes	Sector_1024_bytes
464 * =====================	================	=================
465 *                2-bits                 4-bytes                  4-bytes
466 *                4-bits                 7-bytes                  7-bytes
467 *                8-bits                13-bytes                 14-bytes
468 *               12-bits                20-bytes                 21-bytes
469 *               24-bits                39-bytes                 42-bytes
470 */
471static int pmecc_get_ecc_bytes(int cap, int sector_size)
472{
473	int m = 12 + sector_size / 512;
474	return (m * cap + 7) / 8;
475}
476
477static void pmecc_config_ecc_layout(struct nand_ecclayout *layout,
478				    int oobsize, int ecc_len)
479{
480	int i;
481
482	layout->eccbytes = ecc_len;
483
484	/* ECC will occupy the last ecc_len bytes continuously */
485	for (i = 0; i < ecc_len; i++)
486		layout->eccpos[i] = oobsize - ecc_len + i;
487
488	layout->oobfree[0].offset = PMECC_OOB_RESERVED_BYTES;
489	layout->oobfree[0].length =
490		oobsize - ecc_len - layout->oobfree[0].offset;
491}
492
493static void __iomem *pmecc_get_alpha_to(struct atmel_nand_host *host)
494{
495	int table_size;
496
497	table_size = host->pmecc_sector_size == 512 ?
498		PMECC_LOOKUP_TABLE_SIZE_512 : PMECC_LOOKUP_TABLE_SIZE_1024;
499
500	return host->pmecc_rom_base + host->pmecc_lookup_table_offset +
501			table_size * sizeof(int16_t);
502}
503
504static int pmecc_data_alloc(struct atmel_nand_host *host)
505{
506	const int cap = host->pmecc_corr_cap;
507	int size;
508
509	size = (2 * cap + 1) * sizeof(int16_t);
510	host->pmecc_partial_syn = devm_kzalloc(host->dev, size, GFP_KERNEL);
511	host->pmecc_si = devm_kzalloc(host->dev, size, GFP_KERNEL);
512	host->pmecc_lmu = devm_kzalloc(host->dev,
513			(cap + 1) * sizeof(int16_t), GFP_KERNEL);
514	host->pmecc_smu = devm_kzalloc(host->dev,
515			(cap + 2) * size, GFP_KERNEL);
516
517	size = (cap + 1) * sizeof(int);
518	host->pmecc_mu = devm_kzalloc(host->dev, size, GFP_KERNEL);
519	host->pmecc_dmu = devm_kzalloc(host->dev, size, GFP_KERNEL);
520	host->pmecc_delta = devm_kzalloc(host->dev, size, GFP_KERNEL);
521
522	if (!host->pmecc_partial_syn ||
523		!host->pmecc_si ||
524		!host->pmecc_lmu ||
525		!host->pmecc_smu ||
526		!host->pmecc_mu ||
527		!host->pmecc_dmu ||
528		!host->pmecc_delta)
529		return -ENOMEM;
530
531	return 0;
532}
533
534static void pmecc_gen_syndrome(struct mtd_info *mtd, int sector)
535{
536	struct nand_chip *nand_chip = mtd->priv;
537	struct atmel_nand_host *host = nand_chip->priv;
538	int i;
539	uint32_t value;
540
541	/* Fill odd syndromes */
542	for (i = 0; i < host->pmecc_corr_cap; i++) {
543		value = pmecc_readl_rem_relaxed(host->ecc, sector, i / 2);
544		if (i & 1)
545			value >>= 16;
546		value &= 0xffff;
547		host->pmecc_partial_syn[(2 * i) + 1] = (int16_t)value;
548	}
549}
550
551static void pmecc_substitute(struct mtd_info *mtd)
552{
553	struct nand_chip *nand_chip = mtd->priv;
554	struct atmel_nand_host *host = nand_chip->priv;
555	int16_t __iomem *alpha_to = host->pmecc_alpha_to;
556	int16_t __iomem *index_of = host->pmecc_index_of;
557	int16_t *partial_syn = host->pmecc_partial_syn;
558	const int cap = host->pmecc_corr_cap;
559	int16_t *si;
560	int i, j;
561
562	/* si[] is a table that holds the current syndrome value,
563	 * an element of that table belongs to the field
564	 */
565	si = host->pmecc_si;
566
567	memset(&si[1], 0, sizeof(int16_t) * (2 * cap - 1));
568
569	/* Computation 2t syndromes based on S(x) */
570	/* Odd syndromes */
571	for (i = 1; i < 2 * cap; i += 2) {
572		for (j = 0; j < host->pmecc_degree; j++) {
573			if (partial_syn[i] & ((unsigned short)0x1 << j))
574				si[i] = readw_relaxed(alpha_to + i * j) ^ si[i];
575		}
576	}
577	/* Even syndrome = (Odd syndrome) ** 2 */
578	for (i = 2, j = 1; j <= cap; i = ++j << 1) {
579		if (si[j] == 0) {
580			si[i] = 0;
581		} else {
582			int16_t tmp;
583
584			tmp = readw_relaxed(index_of + si[j]);
585			tmp = (tmp * 2) % host->pmecc_cw_len;
586			si[i] = readw_relaxed(alpha_to + tmp);
587		}
588	}
589
590	return;
591}
592
593static void pmecc_get_sigma(struct mtd_info *mtd)
594{
595	struct nand_chip *nand_chip = mtd->priv;
596	struct atmel_nand_host *host = nand_chip->priv;
597
598	int16_t *lmu = host->pmecc_lmu;
599	int16_t *si = host->pmecc_si;
600	int *mu = host->pmecc_mu;
601	int *dmu = host->pmecc_dmu;	/* Discrepancy */
602	int *delta = host->pmecc_delta; /* Delta order */
603	int cw_len = host->pmecc_cw_len;
604	const int16_t cap = host->pmecc_corr_cap;
605	const int num = 2 * cap + 1;
606	int16_t __iomem	*index_of = host->pmecc_index_of;
607	int16_t __iomem	*alpha_to = host->pmecc_alpha_to;
608	int i, j, k;
609	uint32_t dmu_0_count, tmp;
610	int16_t *smu = host->pmecc_smu;
611
612	/* index of largest delta */
613	int ro;
614	int largest;
615	int diff;
616
617	dmu_0_count = 0;
618
619	/* First Row */
620
621	/* Mu */
622	mu[0] = -1;
623
624	memset(smu, 0, sizeof(int16_t) * num);
625	smu[0] = 1;
626
627	/* discrepancy set to 1 */
628	dmu[0] = 1;
629	/* polynom order set to 0 */
630	lmu[0] = 0;
631	delta[0] = (mu[0] * 2 - lmu[0]) >> 1;
632
633	/* Second Row */
634
635	/* Mu */
636	mu[1] = 0;
637	/* Sigma(x) set to 1 */
638	memset(&smu[num], 0, sizeof(int16_t) * num);
639	smu[num] = 1;
640
641	/* discrepancy set to S1 */
642	dmu[1] = si[1];
643
644	/* polynom order set to 0 */
645	lmu[1] = 0;
646
647	delta[1] = (mu[1] * 2 - lmu[1]) >> 1;
648
649	/* Init the Sigma(x) last row */
650	memset(&smu[(cap + 1) * num], 0, sizeof(int16_t) * num);
651
652	for (i = 1; i <= cap; i++) {
653		mu[i + 1] = i << 1;
654		/* Begin Computing Sigma (Mu+1) and L(mu) */
655		/* check if discrepancy is set to 0 */
656		if (dmu[i] == 0) {
657			dmu_0_count++;
658
659			tmp = ((cap - (lmu[i] >> 1) - 1) / 2);
660			if ((cap - (lmu[i] >> 1) - 1) & 0x1)
661				tmp += 2;
662			else
663				tmp += 1;
664
665			if (dmu_0_count == tmp) {
666				for (j = 0; j <= (lmu[i] >> 1) + 1; j++)
667					smu[(cap + 1) * num + j] =
668							smu[i * num + j];
669
670				lmu[cap + 1] = lmu[i];
671				return;
672			}
673
674			/* copy polynom */
675			for (j = 0; j <= lmu[i] >> 1; j++)
676				smu[(i + 1) * num + j] = smu[i * num + j];
677
678			/* copy previous polynom order to the next */
679			lmu[i + 1] = lmu[i];
680		} else {
681			ro = 0;
682			largest = -1;
683			/* find largest delta with dmu != 0 */
684			for (j = 0; j < i; j++) {
685				if ((dmu[j]) && (delta[j] > largest)) {
686					largest = delta[j];
687					ro = j;
688				}
689			}
690
691			/* compute difference */
692			diff = (mu[i] - mu[ro]);
693
694			/* Compute degree of the new smu polynomial */
695			if ((lmu[i] >> 1) > ((lmu[ro] >> 1) + diff))
696				lmu[i + 1] = lmu[i];
697			else
698				lmu[i + 1] = ((lmu[ro] >> 1) + diff) * 2;
699
700			/* Init smu[i+1] with 0 */
701			for (k = 0; k < num; k++)
702				smu[(i + 1) * num + k] = 0;
703
704			/* Compute smu[i+1] */
705			for (k = 0; k <= lmu[ro] >> 1; k++) {
706				int16_t a, b, c;
707
708				if (!(smu[ro * num + k] && dmu[i]))
709					continue;
710				a = readw_relaxed(index_of + dmu[i]);
711				b = readw_relaxed(index_of + dmu[ro]);
712				c = readw_relaxed(index_of + smu[ro * num + k]);
713				tmp = a + (cw_len - b) + c;
714				a = readw_relaxed(alpha_to + tmp % cw_len);
715				smu[(i + 1) * num + (k + diff)] = a;
716			}
717
718			for (k = 0; k <= lmu[i] >> 1; k++)
719				smu[(i + 1) * num + k] ^= smu[i * num + k];
720		}
721
722		/* End Computing Sigma (Mu+1) and L(mu) */
723		/* In either case compute delta */
724		delta[i + 1] = (mu[i + 1] * 2 - lmu[i + 1]) >> 1;
725
726		/* Do not compute discrepancy for the last iteration */
727		if (i >= cap)
728			continue;
729
730		for (k = 0; k <= (lmu[i + 1] >> 1); k++) {
731			tmp = 2 * (i - 1);
732			if (k == 0) {
733				dmu[i + 1] = si[tmp + 3];
734			} else if (smu[(i + 1) * num + k] && si[tmp + 3 - k]) {
735				int16_t a, b, c;
736				a = readw_relaxed(index_of +
737						smu[(i + 1) * num + k]);
738				b = si[2 * (i - 1) + 3 - k];
739				c = readw_relaxed(index_of + b);
740				tmp = a + c;
741				tmp %= cw_len;
742				dmu[i + 1] = readw_relaxed(alpha_to + tmp) ^
743					dmu[i + 1];
744			}
745		}
746	}
747
748	return;
749}
750
751static int pmecc_err_location(struct mtd_info *mtd)
752{
753	struct nand_chip *nand_chip = mtd->priv;
754	struct atmel_nand_host *host = nand_chip->priv;
755	unsigned long end_time;
756	const int cap = host->pmecc_corr_cap;
757	const int num = 2 * cap + 1;
758	int sector_size = host->pmecc_sector_size;
759	int err_nbr = 0;	/* number of error */
760	int roots_nbr;		/* number of roots */
761	int i;
762	uint32_t val;
763	int16_t *smu = host->pmecc_smu;
764
765	pmerrloc_writel(host->pmerrloc_base, ELDIS, PMERRLOC_DISABLE);
766
767	for (i = 0; i <= host->pmecc_lmu[cap + 1] >> 1; i++) {
768		pmerrloc_writel_sigma_relaxed(host->pmerrloc_base, i,
769				      smu[(cap + 1) * num + i]);
770		err_nbr++;
771	}
772
773	val = (err_nbr - 1) << 16;
774	if (sector_size == 1024)
775		val |= 1;
776
777	pmerrloc_writel(host->pmerrloc_base, ELCFG, val);
778	pmerrloc_writel(host->pmerrloc_base, ELEN,
779			sector_size * 8 + host->pmecc_degree * cap);
780
781	end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
782	while (!(pmerrloc_readl_relaxed(host->pmerrloc_base, ELISR)
783		 & PMERRLOC_CALC_DONE)) {
784		if (unlikely(time_after(jiffies, end_time))) {
785			dev_err(host->dev, "PMECC: Timeout to calculate error location.\n");
786			return -1;
787		}
788		cpu_relax();
789	}
790
791	roots_nbr = (pmerrloc_readl_relaxed(host->pmerrloc_base, ELISR)
792		& PMERRLOC_ERR_NUM_MASK) >> 8;
793	/* Number of roots == degree of smu hence <= cap */
794	if (roots_nbr == host->pmecc_lmu[cap + 1] >> 1)
795		return err_nbr - 1;
796
797	/* Number of roots does not match the degree of smu
798	 * unable to correct error */
799	return -1;
800}
801
802static void pmecc_correct_data(struct mtd_info *mtd, uint8_t *buf, uint8_t *ecc,
803		int sector_num, int extra_bytes, int err_nbr)
804{
805	struct nand_chip *nand_chip = mtd->priv;
806	struct atmel_nand_host *host = nand_chip->priv;
807	int i = 0;
808	int byte_pos, bit_pos, sector_size, pos;
809	uint32_t tmp;
810	uint8_t err_byte;
811
812	sector_size = host->pmecc_sector_size;
813
814	while (err_nbr) {
815		tmp = pmerrloc_readl_el_relaxed(host->pmerrloc_base, i) - 1;
816		byte_pos = tmp / 8;
817		bit_pos  = tmp % 8;
818
819		if (byte_pos >= (sector_size + extra_bytes))
820			BUG();	/* should never happen */
821
822		if (byte_pos < sector_size) {
823			err_byte = *(buf + byte_pos);
824			*(buf + byte_pos) ^= (1 << bit_pos);
825
826			pos = sector_num * host->pmecc_sector_size + byte_pos;
827			dev_info(host->dev, "Bit flip in data area, byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
828				pos, bit_pos, err_byte, *(buf + byte_pos));
829		} else {
830			/* Bit flip in OOB area */
831			tmp = sector_num * nand_chip->ecc.bytes
832					+ (byte_pos - sector_size);
833			err_byte = ecc[tmp];
834			ecc[tmp] ^= (1 << bit_pos);
835
836			pos = tmp + nand_chip->ecc.layout->eccpos[0];
837			dev_info(host->dev, "Bit flip in OOB, oob_byte_pos: %d, bit_pos: %d, 0x%02x -> 0x%02x\n",
838				pos, bit_pos, err_byte, ecc[tmp]);
839		}
840
841		i++;
842		err_nbr--;
843	}
844
845	return;
846}
847
848static int pmecc_correction(struct mtd_info *mtd, u32 pmecc_stat, uint8_t *buf,
849	u8 *ecc)
850{
851	struct nand_chip *nand_chip = mtd->priv;
852	struct atmel_nand_host *host = nand_chip->priv;
853	int i, err_nbr;
854	uint8_t *buf_pos;
855	int max_bitflips = 0;
856
857	/* If can correct bitfilps from erased page, do the normal check */
858	if (host->caps->pmecc_correct_erase_page)
859		goto normal_check;
860
861	for (i = 0; i < nand_chip->ecc.total; i++)
862		if (ecc[i] != 0xff)
863			goto normal_check;
864	/* Erased page, return OK */
865	return 0;
866
867normal_check:
868	for (i = 0; i < nand_chip->ecc.steps; i++) {
869		err_nbr = 0;
870		if (pmecc_stat & 0x1) {
871			buf_pos = buf + i * host->pmecc_sector_size;
872
873			pmecc_gen_syndrome(mtd, i);
874			pmecc_substitute(mtd);
875			pmecc_get_sigma(mtd);
876
877			err_nbr = pmecc_err_location(mtd);
878			if (err_nbr == -1) {
879				dev_err(host->dev, "PMECC: Too many errors\n");
880				mtd->ecc_stats.failed++;
881				return -EIO;
882			} else {
883				pmecc_correct_data(mtd, buf_pos, ecc, i,
884					nand_chip->ecc.bytes, err_nbr);
885				mtd->ecc_stats.corrected += err_nbr;
886				max_bitflips = max_t(int, max_bitflips, err_nbr);
887			}
888		}
889		pmecc_stat >>= 1;
890	}
891
892	return max_bitflips;
893}
894
895static void pmecc_enable(struct atmel_nand_host *host, int ecc_op)
896{
897	u32 val;
898
899	if (ecc_op != NAND_ECC_READ && ecc_op != NAND_ECC_WRITE) {
900		dev_err(host->dev, "atmel_nand: wrong pmecc operation type!");
901		return;
902	}
903
904	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
905	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
906	val = pmecc_readl_relaxed(host->ecc, CFG);
907
908	if (ecc_op == NAND_ECC_READ)
909		pmecc_writel(host->ecc, CFG, (val & ~PMECC_CFG_WRITE_OP)
910			| PMECC_CFG_AUTO_ENABLE);
911	else
912		pmecc_writel(host->ecc, CFG, (val | PMECC_CFG_WRITE_OP)
913			& ~PMECC_CFG_AUTO_ENABLE);
914
915	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
916	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DATA);
917}
918
919static int atmel_nand_pmecc_read_page(struct mtd_info *mtd,
920	struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
921{
922	struct atmel_nand_host *host = chip->priv;
923	int eccsize = chip->ecc.size * chip->ecc.steps;
924	uint8_t *oob = chip->oob_poi;
925	uint32_t *eccpos = chip->ecc.layout->eccpos;
926	uint32_t stat;
927	unsigned long end_time;
928	int bitflips = 0;
929
930	if (!host->nfc || !host->nfc->use_nfc_sram)
931		pmecc_enable(host, NAND_ECC_READ);
932
933	chip->read_buf(mtd, buf, eccsize);
934	chip->read_buf(mtd, oob, mtd->oobsize);
935
936	end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
937	while ((pmecc_readl_relaxed(host->ecc, SR) & PMECC_SR_BUSY)) {
938		if (unlikely(time_after(jiffies, end_time))) {
939			dev_err(host->dev, "PMECC: Timeout to get error status.\n");
940			return -EIO;
941		}
942		cpu_relax();
943	}
944
945	stat = pmecc_readl_relaxed(host->ecc, ISR);
946	if (stat != 0) {
947		bitflips = pmecc_correction(mtd, stat, buf, &oob[eccpos[0]]);
948		if (bitflips < 0)
949			/* uncorrectable errors */
950			return 0;
951	}
952
953	return bitflips;
954}
955
956static int atmel_nand_pmecc_write_page(struct mtd_info *mtd,
957		struct nand_chip *chip, const uint8_t *buf, int oob_required,
958		int page)
959{
960	struct atmel_nand_host *host = chip->priv;
961	uint32_t *eccpos = chip->ecc.layout->eccpos;
962	int i, j;
963	unsigned long end_time;
964
965	if (!host->nfc || !host->nfc->write_by_sram) {
966		pmecc_enable(host, NAND_ECC_WRITE);
967		chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
968	}
969
970	end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
971	while ((pmecc_readl_relaxed(host->ecc, SR) & PMECC_SR_BUSY)) {
972		if (unlikely(time_after(jiffies, end_time))) {
973			dev_err(host->dev, "PMECC: Timeout to get ECC value.\n");
974			return -EIO;
975		}
976		cpu_relax();
977	}
978
979	for (i = 0; i < chip->ecc.steps; i++) {
980		for (j = 0; j < chip->ecc.bytes; j++) {
981			int pos;
982
983			pos = i * chip->ecc.bytes + j;
984			chip->oob_poi[eccpos[pos]] =
985				pmecc_readb_ecc_relaxed(host->ecc, i, j);
986		}
987	}
988	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
989
990	return 0;
991}
992
993static void atmel_pmecc_core_init(struct mtd_info *mtd)
994{
995	struct nand_chip *nand_chip = mtd->priv;
996	struct atmel_nand_host *host = nand_chip->priv;
997	uint32_t val = 0;
998	struct nand_ecclayout *ecc_layout;
999
1000	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
1001	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
1002
1003	switch (host->pmecc_corr_cap) {
1004	case 2:
1005		val = PMECC_CFG_BCH_ERR2;
1006		break;
1007	case 4:
1008		val = PMECC_CFG_BCH_ERR4;
1009		break;
1010	case 8:
1011		val = PMECC_CFG_BCH_ERR8;
1012		break;
1013	case 12:
1014		val = PMECC_CFG_BCH_ERR12;
1015		break;
1016	case 24:
1017		val = PMECC_CFG_BCH_ERR24;
1018		break;
1019	}
1020
1021	if (host->pmecc_sector_size == 512)
1022		val |= PMECC_CFG_SECTOR512;
1023	else if (host->pmecc_sector_size == 1024)
1024		val |= PMECC_CFG_SECTOR1024;
1025
1026	switch (nand_chip->ecc.steps) {
1027	case 1:
1028		val |= PMECC_CFG_PAGE_1SECTOR;
1029		break;
1030	case 2:
1031		val |= PMECC_CFG_PAGE_2SECTORS;
1032		break;
1033	case 4:
1034		val |= PMECC_CFG_PAGE_4SECTORS;
1035		break;
1036	case 8:
1037		val |= PMECC_CFG_PAGE_8SECTORS;
1038		break;
1039	}
1040
1041	val |= (PMECC_CFG_READ_OP | PMECC_CFG_SPARE_DISABLE
1042		| PMECC_CFG_AUTO_DISABLE);
1043	pmecc_writel(host->ecc, CFG, val);
1044
1045	ecc_layout = nand_chip->ecc.layout;
1046	pmecc_writel(host->ecc, SAREA, mtd->oobsize - 1);
1047	pmecc_writel(host->ecc, SADDR, ecc_layout->eccpos[0]);
1048	pmecc_writel(host->ecc, EADDR,
1049			ecc_layout->eccpos[ecc_layout->eccbytes - 1]);
1050	/* See datasheet about PMECC Clock Control Register */
1051	pmecc_writel(host->ecc, CLK, 2);
1052	pmecc_writel(host->ecc, IDR, 0xff);
1053	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
1054}
1055
1056/*
1057 * Get minimum ecc requirements from NAND.
1058 * If pmecc-cap, pmecc-sector-size in DTS are not specified, this function
1059 * will set them according to minimum ecc requirement. Otherwise, use the
1060 * value in DTS file.
1061 * return 0 if success. otherwise return error code.
1062 */
1063static int pmecc_choose_ecc(struct atmel_nand_host *host,
1064		int *cap, int *sector_size)
1065{
1066	/* Get minimum ECC requirements */
1067	if (host->nand_chip.ecc_strength_ds) {
1068		*cap = host->nand_chip.ecc_strength_ds;
1069		*sector_size = host->nand_chip.ecc_step_ds;
1070		dev_info(host->dev, "minimum ECC: %d bits in %d bytes\n",
1071				*cap, *sector_size);
1072	} else {
1073		*cap = 2;
1074		*sector_size = 512;
1075		dev_info(host->dev, "can't detect min. ECC, assume 2 bits in 512 bytes\n");
1076	}
1077
1078	/* If device tree doesn't specify, use NAND's minimum ECC parameters */
1079	if (host->pmecc_corr_cap == 0) {
1080		/* use the most fitable ecc bits (the near bigger one ) */
1081		if (*cap <= 2)
1082			host->pmecc_corr_cap = 2;
1083		else if (*cap <= 4)
1084			host->pmecc_corr_cap = 4;
1085		else if (*cap <= 8)
1086			host->pmecc_corr_cap = 8;
1087		else if (*cap <= 12)
1088			host->pmecc_corr_cap = 12;
1089		else if (*cap <= 24)
1090			host->pmecc_corr_cap = 24;
1091		else
1092			return -EINVAL;
1093	}
1094	if (host->pmecc_sector_size == 0) {
1095		/* use the most fitable sector size (the near smaller one ) */
1096		if (*sector_size >= 1024)
1097			host->pmecc_sector_size = 1024;
1098		else if (*sector_size >= 512)
1099			host->pmecc_sector_size = 512;
1100		else
1101			return -EINVAL;
1102	}
1103	return 0;
1104}
1105
1106static inline int deg(unsigned int poly)
1107{
1108	/* polynomial degree is the most-significant bit index */
1109	return fls(poly) - 1;
1110}
1111
1112static int build_gf_tables(int mm, unsigned int poly,
1113		int16_t *index_of, int16_t *alpha_to)
1114{
1115	unsigned int i, x = 1;
1116	const unsigned int k = 1 << deg(poly);
1117	unsigned int nn = (1 << mm) - 1;
1118
1119	/* primitive polynomial must be of degree m */
1120	if (k != (1u << mm))
1121		return -EINVAL;
1122
1123	for (i = 0; i < nn; i++) {
1124		alpha_to[i] = x;
1125		index_of[x] = i;
1126		if (i && (x == 1))
1127			/* polynomial is not primitive (a^i=1 with 0<i<2^m-1) */
1128			return -EINVAL;
1129		x <<= 1;
1130		if (x & k)
1131			x ^= poly;
1132	}
1133	alpha_to[nn] = 1;
1134	index_of[0] = 0;
1135
1136	return 0;
1137}
1138
1139static uint16_t *create_lookup_table(struct device *dev, int sector_size)
1140{
1141	int degree = (sector_size == 512) ?
1142			PMECC_GF_DIMENSION_13 :
1143			PMECC_GF_DIMENSION_14;
1144	unsigned int poly = (sector_size == 512) ?
1145			PMECC_GF_13_PRIMITIVE_POLY :
1146			PMECC_GF_14_PRIMITIVE_POLY;
1147	int table_size = (sector_size == 512) ?
1148			PMECC_LOOKUP_TABLE_SIZE_512 :
1149			PMECC_LOOKUP_TABLE_SIZE_1024;
1150
1151	int16_t *addr = devm_kzalloc(dev, 2 * table_size * sizeof(uint16_t),
1152			GFP_KERNEL);
1153	if (addr && build_gf_tables(degree, poly, addr, addr + table_size))
1154		return NULL;
1155
1156	return addr;
1157}
1158
1159static int atmel_pmecc_nand_init_params(struct platform_device *pdev,
1160					 struct atmel_nand_host *host)
1161{
1162	struct mtd_info *mtd = &host->mtd;
1163	struct nand_chip *nand_chip = &host->nand_chip;
1164	struct resource *regs, *regs_pmerr, *regs_rom;
1165	uint16_t *galois_table;
1166	int cap, sector_size, err_no;
1167
1168	err_no = pmecc_choose_ecc(host, &cap, &sector_size);
1169	if (err_no) {
1170		dev_err(host->dev, "The NAND flash's ECC requirement are not support!");
1171		return err_no;
1172	}
1173
1174	if (cap > host->pmecc_corr_cap ||
1175			sector_size != host->pmecc_sector_size)
1176		dev_info(host->dev, "WARNING: Be Caution! Using different PMECC parameters from Nand ONFI ECC reqirement.\n");
1177
1178	cap = host->pmecc_corr_cap;
1179	sector_size = host->pmecc_sector_size;
1180	host->pmecc_lookup_table_offset = (sector_size == 512) ?
1181			host->pmecc_lookup_table_offset_512 :
1182			host->pmecc_lookup_table_offset_1024;
1183
1184	dev_info(host->dev, "Initialize PMECC params, cap: %d, sector: %d\n",
1185		 cap, sector_size);
1186
1187	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1188	if (!regs) {
1189		dev_warn(host->dev,
1190			"Can't get I/O resource regs for PMECC controller, rolling back on software ECC\n");
1191		nand_chip->ecc.mode = NAND_ECC_SOFT;
1192		return 0;
1193	}
1194
1195	host->ecc = devm_ioremap_resource(&pdev->dev, regs);
1196	if (IS_ERR(host->ecc)) {
1197		err_no = PTR_ERR(host->ecc);
1198		goto err;
1199	}
1200
1201	regs_pmerr = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1202	host->pmerrloc_base = devm_ioremap_resource(&pdev->dev, regs_pmerr);
1203	if (IS_ERR(host->pmerrloc_base)) {
1204		err_no = PTR_ERR(host->pmerrloc_base);
1205		goto err;
1206	}
1207
1208	if (!host->has_no_lookup_table) {
1209		regs_rom = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1210		host->pmecc_rom_base = devm_ioremap_resource(&pdev->dev,
1211								regs_rom);
1212		if (IS_ERR(host->pmecc_rom_base)) {
1213			dev_err(host->dev, "Can not get I/O resource for ROM, will build a lookup table in runtime!\n");
1214			host->has_no_lookup_table = true;
1215		}
1216	}
1217
1218	if (host->has_no_lookup_table) {
1219		/* Build the look-up table in runtime */
1220		galois_table = create_lookup_table(host->dev, sector_size);
1221		if (!galois_table) {
1222			dev_err(host->dev, "Failed to build a lookup table in runtime!\n");
1223			err_no = -EINVAL;
1224			goto err;
1225		}
1226
1227		host->pmecc_rom_base = (void __iomem *)galois_table;
1228		host->pmecc_lookup_table_offset = 0;
1229	}
1230
1231	nand_chip->ecc.size = sector_size;
1232
1233	/* set ECC page size and oob layout */
1234	switch (mtd->writesize) {
1235	case 512:
1236	case 1024:
1237	case 2048:
1238	case 4096:
1239	case 8192:
1240		if (sector_size > mtd->writesize) {
1241			dev_err(host->dev, "pmecc sector size is bigger than the page size!\n");
1242			err_no = -EINVAL;
1243			goto err;
1244		}
1245
1246		host->pmecc_degree = (sector_size == 512) ?
1247			PMECC_GF_DIMENSION_13 : PMECC_GF_DIMENSION_14;
1248		host->pmecc_cw_len = (1 << host->pmecc_degree) - 1;
1249		host->pmecc_alpha_to = pmecc_get_alpha_to(host);
1250		host->pmecc_index_of = host->pmecc_rom_base +
1251			host->pmecc_lookup_table_offset;
1252
1253		nand_chip->ecc.strength = cap;
1254		nand_chip->ecc.bytes = pmecc_get_ecc_bytes(cap, sector_size);
1255		nand_chip->ecc.steps = mtd->writesize / sector_size;
1256		nand_chip->ecc.total = nand_chip->ecc.bytes *
1257			nand_chip->ecc.steps;
1258		if (nand_chip->ecc.total >
1259				mtd->oobsize - PMECC_OOB_RESERVED_BYTES) {
1260			dev_err(host->dev, "No room for ECC bytes\n");
1261			err_no = -EINVAL;
1262			goto err;
1263		}
1264		pmecc_config_ecc_layout(&atmel_pmecc_oobinfo,
1265					mtd->oobsize,
1266					nand_chip->ecc.total);
1267
1268		nand_chip->ecc.layout = &atmel_pmecc_oobinfo;
1269		break;
1270	default:
1271		dev_warn(host->dev,
1272			"Unsupported page size for PMECC, use Software ECC\n");
1273		/* page size not handled by HW ECC */
1274		/* switching back to soft ECC */
1275		nand_chip->ecc.mode = NAND_ECC_SOFT;
1276		return 0;
1277	}
1278
1279	/* Allocate data for PMECC computation */
1280	err_no = pmecc_data_alloc(host);
1281	if (err_no) {
1282		dev_err(host->dev,
1283				"Cannot allocate memory for PMECC computation!\n");
1284		goto err;
1285	}
1286
1287	nand_chip->options |= NAND_NO_SUBPAGE_WRITE;
1288	nand_chip->ecc.read_page = atmel_nand_pmecc_read_page;
1289	nand_chip->ecc.write_page = atmel_nand_pmecc_write_page;
1290
1291	atmel_pmecc_core_init(mtd);
1292
1293	return 0;
1294
1295err:
1296	return err_no;
1297}
1298
1299/*
1300 * Calculate HW ECC
1301 *
1302 * function called after a write
1303 *
1304 * mtd:        MTD block structure
1305 * dat:        raw data (unused)
1306 * ecc_code:   buffer for ECC
1307 */
1308static int atmel_nand_calculate(struct mtd_info *mtd,
1309		const u_char *dat, unsigned char *ecc_code)
1310{
1311	struct nand_chip *nand_chip = mtd->priv;
1312	struct atmel_nand_host *host = nand_chip->priv;
1313	unsigned int ecc_value;
1314
1315	/* get the first 2 ECC bytes */
1316	ecc_value = ecc_readl(host->ecc, PR);
1317
1318	ecc_code[0] = ecc_value & 0xFF;
1319	ecc_code[1] = (ecc_value >> 8) & 0xFF;
1320
1321	/* get the last 2 ECC bytes */
1322	ecc_value = ecc_readl(host->ecc, NPR) & ATMEL_ECC_NPARITY;
1323
1324	ecc_code[2] = ecc_value & 0xFF;
1325	ecc_code[3] = (ecc_value >> 8) & 0xFF;
1326
1327	return 0;
1328}
1329
1330/*
1331 * HW ECC read page function
1332 *
1333 * mtd:        mtd info structure
1334 * chip:       nand chip info structure
1335 * buf:        buffer to store read data
1336 * oob_required:    caller expects OOB data read to chip->oob_poi
1337 */
1338static int atmel_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
1339				uint8_t *buf, int oob_required, int page)
1340{
1341	int eccsize = chip->ecc.size;
1342	int eccbytes = chip->ecc.bytes;
1343	uint32_t *eccpos = chip->ecc.layout->eccpos;
1344	uint8_t *p = buf;
1345	uint8_t *oob = chip->oob_poi;
1346	uint8_t *ecc_pos;
1347	int stat;
1348	unsigned int max_bitflips = 0;
1349
1350	/*
1351	 * Errata: ALE is incorrectly wired up to the ECC controller
1352	 * on the AP7000, so it will include the address cycles in the
1353	 * ECC calculation.
1354	 *
1355	 * Workaround: Reset the parity registers before reading the
1356	 * actual data.
1357	 */
1358	struct atmel_nand_host *host = chip->priv;
1359	if (host->board.need_reset_workaround)
1360		ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
1361
1362	/* read the page */
1363	chip->read_buf(mtd, p, eccsize);
1364
1365	/* move to ECC position if needed */
1366	if (eccpos[0] != 0) {
1367		/* This only works on large pages
1368		 * because the ECC controller waits for
1369		 * NAND_CMD_RNDOUTSTART after the
1370		 * NAND_CMD_RNDOUT.
1371		 * anyway, for small pages, the eccpos[0] == 0
1372		 */
1373		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
1374				mtd->writesize + eccpos[0], -1);
1375	}
1376
1377	/* the ECC controller needs to read the ECC just after the data */
1378	ecc_pos = oob + eccpos[0];
1379	chip->read_buf(mtd, ecc_pos, eccbytes);
1380
1381	/* check if there's an error */
1382	stat = chip->ecc.correct(mtd, p, oob, NULL);
1383
1384	if (stat < 0) {
1385		mtd->ecc_stats.failed++;
1386	} else {
1387		mtd->ecc_stats.corrected += stat;
1388		max_bitflips = max_t(unsigned int, max_bitflips, stat);
1389	}
1390
1391	/* get back to oob start (end of page) */
1392	chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
1393
1394	/* read the oob */
1395	chip->read_buf(mtd, oob, mtd->oobsize);
1396
1397	return max_bitflips;
1398}
1399
1400/*
1401 * HW ECC Correction
1402 *
1403 * function called after a read
1404 *
1405 * mtd:        MTD block structure
1406 * dat:        raw data read from the chip
1407 * read_ecc:   ECC from the chip (unused)
1408 * isnull:     unused
1409 *
1410 * Detect and correct a 1 bit error for a page
1411 */
1412static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
1413		u_char *read_ecc, u_char *isnull)
1414{
1415	struct nand_chip *nand_chip = mtd->priv;
1416	struct atmel_nand_host *host = nand_chip->priv;
1417	unsigned int ecc_status;
1418	unsigned int ecc_word, ecc_bit;
1419
1420	/* get the status from the Status Register */
1421	ecc_status = ecc_readl(host->ecc, SR);
1422
1423	/* if there's no error */
1424	if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
1425		return 0;
1426
1427	/* get error bit offset (4 bits) */
1428	ecc_bit = ecc_readl(host->ecc, PR) & ATMEL_ECC_BITADDR;
1429	/* get word address (12 bits) */
1430	ecc_word = ecc_readl(host->ecc, PR) & ATMEL_ECC_WORDADDR;
1431	ecc_word >>= 4;
1432
1433	/* if there are multiple errors */
1434	if (ecc_status & ATMEL_ECC_MULERR) {
1435		/* check if it is a freshly erased block
1436		 * (filled with 0xff) */
1437		if ((ecc_bit == ATMEL_ECC_BITADDR)
1438				&& (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
1439			/* the block has just been erased, return OK */
1440			return 0;
1441		}
1442		/* it doesn't seems to be a freshly
1443		 * erased block.
1444		 * We can't correct so many errors */
1445		dev_dbg(host->dev, "atmel_nand : multiple errors detected."
1446				" Unable to correct.\n");
1447		return -EIO;
1448	}
1449
1450	/* if there's a single bit error : we can correct it */
1451	if (ecc_status & ATMEL_ECC_ECCERR) {
1452		/* there's nothing much to do here.
1453		 * the bit error is on the ECC itself.
1454		 */
1455		dev_dbg(host->dev, "atmel_nand : one bit error on ECC code."
1456				" Nothing to correct\n");
1457		return 0;
1458	}
1459
1460	dev_dbg(host->dev, "atmel_nand : one bit error on data."
1461			" (word offset in the page :"
1462			" 0x%x bit offset : 0x%x)\n",
1463			ecc_word, ecc_bit);
1464	/* correct the error */
1465	if (nand_chip->options & NAND_BUSWIDTH_16) {
1466		/* 16 bits words */
1467		((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
1468	} else {
1469		/* 8 bits words */
1470		dat[ecc_word] ^= (1 << ecc_bit);
1471	}
1472	dev_dbg(host->dev, "atmel_nand : error corrected\n");
1473	return 1;
1474}
1475
1476/*
1477 * Enable HW ECC : unused on most chips
1478 */
1479static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
1480{
1481	struct nand_chip *nand_chip = mtd->priv;
1482	struct atmel_nand_host *host = nand_chip->priv;
1483
1484	if (host->board.need_reset_workaround)
1485		ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
1486}
1487
1488static const struct of_device_id atmel_nand_dt_ids[];
1489
1490static int atmel_of_init_port(struct atmel_nand_host *host,
1491			      struct device_node *np)
1492{
1493	u32 val;
1494	u32 offset[2];
1495	int ecc_mode;
1496	struct atmel_nand_data *board = &host->board;
1497	enum of_gpio_flags flags = 0;
1498
1499	host->caps = (struct atmel_nand_caps *)
1500		of_match_device(atmel_nand_dt_ids, host->dev)->data;
1501
1502	if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) {
1503		if (val >= 32) {
1504			dev_err(host->dev, "invalid addr-offset %u\n", val);
1505			return -EINVAL;
1506		}
1507		board->ale = val;
1508	}
1509
1510	if (of_property_read_u32(np, "atmel,nand-cmd-offset", &val) == 0) {
1511		if (val >= 32) {
1512			dev_err(host->dev, "invalid cmd-offset %u\n", val);
1513			return -EINVAL;
1514		}
1515		board->cle = val;
1516	}
1517
1518	ecc_mode = of_get_nand_ecc_mode(np);
1519
1520	board->ecc_mode = ecc_mode < 0 ? NAND_ECC_SOFT : ecc_mode;
1521
1522	board->on_flash_bbt = of_get_nand_on_flash_bbt(np);
1523
1524	board->has_dma = of_property_read_bool(np, "atmel,nand-has-dma");
1525
1526	if (of_get_nand_bus_width(np) == 16)
1527		board->bus_width_16 = 1;
1528
1529	board->rdy_pin = of_get_gpio_flags(np, 0, &flags);
1530	board->rdy_pin_active_low = (flags == OF_GPIO_ACTIVE_LOW);
1531
1532	board->enable_pin = of_get_gpio(np, 1);
1533	board->det_pin = of_get_gpio(np, 2);
1534
1535	host->has_pmecc = of_property_read_bool(np, "atmel,has-pmecc");
1536
1537	/* load the nfc driver if there is */
1538	of_platform_populate(np, NULL, NULL, host->dev);
1539
1540	if (!(board->ecc_mode == NAND_ECC_HW) || !host->has_pmecc)
1541		return 0;	/* Not using PMECC */
1542
1543	/* use PMECC, get correction capability, sector size and lookup
1544	 * table offset.
1545	 * If correction bits and sector size are not specified, then find
1546	 * them from NAND ONFI parameters.
1547	 */
1548	if (of_property_read_u32(np, "atmel,pmecc-cap", &val) == 0) {
1549		if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
1550				(val != 24)) {
1551			dev_err(host->dev,
1552				"Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
1553				val);
1554			return -EINVAL;
1555		}
1556		host->pmecc_corr_cap = (u8)val;
1557	}
1558
1559	if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) == 0) {
1560		if ((val != 512) && (val != 1024)) {
1561			dev_err(host->dev,
1562				"Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
1563				val);
1564			return -EINVAL;
1565		}
1566		host->pmecc_sector_size = (u16)val;
1567	}
1568
1569	if (of_property_read_u32_array(np, "atmel,pmecc-lookup-table-offset",
1570			offset, 2) != 0) {
1571		dev_err(host->dev, "Cannot get PMECC lookup table offset, will build a lookup table in runtime.\n");
1572		host->has_no_lookup_table = true;
1573		/* Will build a lookup table and initialize the offset later */
1574		return 0;
1575	}
1576	if (!offset[0] && !offset[1]) {
1577		dev_err(host->dev, "Invalid PMECC lookup table offset\n");
1578		return -EINVAL;
1579	}
1580	host->pmecc_lookup_table_offset_512 = offset[0];
1581	host->pmecc_lookup_table_offset_1024 = offset[1];
1582
1583	return 0;
1584}
1585
1586static int atmel_hw_nand_init_params(struct platform_device *pdev,
1587					 struct atmel_nand_host *host)
1588{
1589	struct mtd_info *mtd = &host->mtd;
1590	struct nand_chip *nand_chip = &host->nand_chip;
1591	struct resource		*regs;
1592
1593	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1594	if (!regs) {
1595		dev_err(host->dev,
1596			"Can't get I/O resource regs, use software ECC\n");
1597		nand_chip->ecc.mode = NAND_ECC_SOFT;
1598		return 0;
1599	}
1600
1601	host->ecc = devm_ioremap_resource(&pdev->dev, regs);
1602	if (IS_ERR(host->ecc))
1603		return PTR_ERR(host->ecc);
1604
1605	/* ECC is calculated for the whole page (1 step) */
1606	nand_chip->ecc.size = mtd->writesize;
1607
1608	/* set ECC page size and oob layout */
1609	switch (mtd->writesize) {
1610	case 512:
1611		nand_chip->ecc.layout = &atmel_oobinfo_small;
1612		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_528);
1613		break;
1614	case 1024:
1615		nand_chip->ecc.layout = &atmel_oobinfo_large;
1616		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_1056);
1617		break;
1618	case 2048:
1619		nand_chip->ecc.layout = &atmel_oobinfo_large;
1620		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_2112);
1621		break;
1622	case 4096:
1623		nand_chip->ecc.layout = &atmel_oobinfo_large;
1624		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_4224);
1625		break;
1626	default:
1627		/* page size not handled by HW ECC */
1628		/* switching back to soft ECC */
1629		nand_chip->ecc.mode = NAND_ECC_SOFT;
1630		return 0;
1631	}
1632
1633	/* set up for HW ECC */
1634	nand_chip->ecc.calculate = atmel_nand_calculate;
1635	nand_chip->ecc.correct = atmel_nand_correct;
1636	nand_chip->ecc.hwctl = atmel_nand_hwctl;
1637	nand_chip->ecc.read_page = atmel_nand_read_page;
1638	nand_chip->ecc.bytes = 4;
1639	nand_chip->ecc.strength = 1;
1640
1641	return 0;
1642}
1643
1644static inline u32 nfc_read_status(struct atmel_nand_host *host)
1645{
1646	u32 err_flags = NFC_SR_DTOE | NFC_SR_UNDEF | NFC_SR_AWB | NFC_SR_ASE;
1647	u32 nfc_status = nfc_readl(host->nfc->hsmc_regs, SR);
1648
1649	if (unlikely(nfc_status & err_flags)) {
1650		if (nfc_status & NFC_SR_DTOE)
1651			dev_err(host->dev, "NFC: Waiting Nand R/B Timeout Error\n");
1652		else if (nfc_status & NFC_SR_UNDEF)
1653			dev_err(host->dev, "NFC: Access Undefined Area Error\n");
1654		else if (nfc_status & NFC_SR_AWB)
1655			dev_err(host->dev, "NFC: Access memory While NFC is busy\n");
1656		else if (nfc_status & NFC_SR_ASE)
1657			dev_err(host->dev, "NFC: Access memory Size Error\n");
1658	}
1659
1660	return nfc_status;
1661}
1662
1663/* SMC interrupt service routine */
1664static irqreturn_t hsmc_interrupt(int irq, void *dev_id)
1665{
1666	struct atmel_nand_host *host = dev_id;
1667	u32 status, mask, pending;
1668	irqreturn_t ret = IRQ_NONE;
1669
1670	status = nfc_read_status(host);
1671	mask = nfc_readl(host->nfc->hsmc_regs, IMR);
1672	pending = status & mask;
1673
1674	if (pending & NFC_SR_XFR_DONE) {
1675		complete(&host->nfc->comp_xfer_done);
1676		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_XFR_DONE);
1677		ret = IRQ_HANDLED;
1678	}
1679	if (pending & NFC_SR_RB_EDGE) {
1680		complete(&host->nfc->comp_ready);
1681		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_RB_EDGE);
1682		ret = IRQ_HANDLED;
1683	}
1684	if (pending & NFC_SR_CMD_DONE) {
1685		complete(&host->nfc->comp_cmd_done);
1686		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_CMD_DONE);
1687		ret = IRQ_HANDLED;
1688	}
1689
1690	return ret;
1691}
1692
1693/* NFC(Nand Flash Controller) related functions */
1694static void nfc_prepare_interrupt(struct atmel_nand_host *host, u32 flag)
1695{
1696	if (flag & NFC_SR_XFR_DONE)
1697		init_completion(&host->nfc->comp_xfer_done);
1698
1699	if (flag & NFC_SR_RB_EDGE)
1700		init_completion(&host->nfc->comp_ready);
1701
1702	if (flag & NFC_SR_CMD_DONE)
1703		init_completion(&host->nfc->comp_cmd_done);
1704
1705	/* Enable interrupt that need to wait for */
1706	nfc_writel(host->nfc->hsmc_regs, IER, flag);
1707}
1708
1709static int nfc_wait_interrupt(struct atmel_nand_host *host, u32 flag)
1710{
1711	int i, index = 0;
1712	struct completion *comp[3];	/* Support 3 interrupt completion */
1713
1714	if (flag & NFC_SR_XFR_DONE)
1715		comp[index++] = &host->nfc->comp_xfer_done;
1716
1717	if (flag & NFC_SR_RB_EDGE)
1718		comp[index++] = &host->nfc->comp_ready;
1719
1720	if (flag & NFC_SR_CMD_DONE)
1721		comp[index++] = &host->nfc->comp_cmd_done;
1722
1723	if (index == 0) {
1724		dev_err(host->dev, "Unknown interrupt flag: 0x%08x\n", flag);
1725		return -EINVAL;
1726	}
1727
1728	for (i = 0; i < index; i++) {
1729		if (wait_for_completion_timeout(comp[i],
1730				msecs_to_jiffies(NFC_TIME_OUT_MS)))
1731			continue;	/* wait for next completion */
1732		else
1733			goto err_timeout;
1734	}
1735
1736	return 0;
1737
1738err_timeout:
1739	dev_err(host->dev, "Time out to wait for interrupt: 0x%08x\n", flag);
1740	/* Disable the interrupt as it is not handled by interrupt handler */
1741	nfc_writel(host->nfc->hsmc_regs, IDR, flag);
1742	return -ETIMEDOUT;
1743}
1744
1745static int nfc_send_command(struct atmel_nand_host *host,
1746	unsigned int cmd, unsigned int addr, unsigned char cycle0)
1747{
1748	unsigned long timeout;
1749	u32 flag = NFC_SR_CMD_DONE;
1750	flag |= cmd & NFCADDR_CMD_DATAEN ? NFC_SR_XFR_DONE : 0;
1751
1752	dev_dbg(host->dev,
1753		"nfc_cmd: 0x%08x, addr1234: 0x%08x, cycle0: 0x%02x\n",
1754		cmd, addr, cycle0);
1755
1756	timeout = jiffies + msecs_to_jiffies(NFC_TIME_OUT_MS);
1757	while (nfc_readl(host->nfc->hsmc_regs, SR) & NFC_SR_BUSY) {
1758		if (time_after(jiffies, timeout)) {
1759			dev_err(host->dev,
1760				"Time out to wait for NFC ready!\n");
1761			return -ETIMEDOUT;
1762		}
1763	}
1764
1765	nfc_prepare_interrupt(host, flag);
1766	nfc_writel(host->nfc->hsmc_regs, CYCLE0, cycle0);
1767	nfc_cmd_addr1234_writel(cmd, addr, host->nfc->base_cmd_regs);
1768	return nfc_wait_interrupt(host, flag);
1769}
1770
1771static int nfc_device_ready(struct mtd_info *mtd)
1772{
1773	u32 status, mask;
1774	struct nand_chip *nand_chip = mtd->priv;
1775	struct atmel_nand_host *host = nand_chip->priv;
1776
1777	status = nfc_read_status(host);
1778	mask = nfc_readl(host->nfc->hsmc_regs, IMR);
1779
1780	/* The mask should be 0. If not we may lost interrupts */
1781	if (unlikely(mask & status))
1782		dev_err(host->dev, "Lost the interrupt flags: 0x%08x\n",
1783				mask & status);
1784
1785	return status & NFC_SR_RB_EDGE;
1786}
1787
1788static void nfc_select_chip(struct mtd_info *mtd, int chip)
1789{
1790	struct nand_chip *nand_chip = mtd->priv;
1791	struct atmel_nand_host *host = nand_chip->priv;
1792
1793	if (chip == -1)
1794		nfc_writel(host->nfc->hsmc_regs, CTRL, NFC_CTRL_DISABLE);
1795	else
1796		nfc_writel(host->nfc->hsmc_regs, CTRL, NFC_CTRL_ENABLE);
1797}
1798
1799static int nfc_make_addr(struct mtd_info *mtd, int command, int column,
1800		int page_addr, unsigned int *addr1234, unsigned int *cycle0)
1801{
1802	struct nand_chip *chip = mtd->priv;
1803
1804	int acycle = 0;
1805	unsigned char addr_bytes[8];
1806	int index = 0, bit_shift;
1807
1808	BUG_ON(addr1234 == NULL || cycle0 == NULL);
1809
1810	*cycle0 = 0;
1811	*addr1234 = 0;
1812
1813	if (column != -1) {
1814		if (chip->options & NAND_BUSWIDTH_16 &&
1815				!nand_opcode_8bits(command))
1816			column >>= 1;
1817		addr_bytes[acycle++] = column & 0xff;
1818		if (mtd->writesize > 512)
1819			addr_bytes[acycle++] = (column >> 8) & 0xff;
1820	}
1821
1822	if (page_addr != -1) {
1823		addr_bytes[acycle++] = page_addr & 0xff;
1824		addr_bytes[acycle++] = (page_addr >> 8) & 0xff;
1825		if (chip->chipsize > (128 << 20))
1826			addr_bytes[acycle++] = (page_addr >> 16) & 0xff;
1827	}
1828
1829	if (acycle > 4)
1830		*cycle0 = addr_bytes[index++];
1831
1832	for (bit_shift = 0; index < acycle; bit_shift += 8)
1833		*addr1234 += addr_bytes[index++] << bit_shift;
1834
1835	/* return acycle in cmd register */
1836	return acycle << NFCADDR_CMD_ACYCLE_BIT_POS;
1837}
1838
1839static void nfc_nand_command(struct mtd_info *mtd, unsigned int command,
1840				int column, int page_addr)
1841{
1842	struct nand_chip *chip = mtd->priv;
1843	struct atmel_nand_host *host = chip->priv;
1844	unsigned long timeout;
1845	unsigned int nfc_addr_cmd = 0;
1846
1847	unsigned int cmd1 = command << NFCADDR_CMD_CMD1_BIT_POS;
1848
1849	/* Set default settings: no cmd2, no addr cycle. read from nand */
1850	unsigned int cmd2 = 0;
1851	unsigned int vcmd2 = 0;
1852	int acycle = NFCADDR_CMD_ACYCLE_NONE;
1853	int csid = NFCADDR_CMD_CSID_3;
1854	int dataen = NFCADDR_CMD_DATADIS;
1855	int nfcwr = NFCADDR_CMD_NFCRD;
1856	unsigned int addr1234 = 0;
1857	unsigned int cycle0 = 0;
1858	bool do_addr = true;
1859	host->nfc->data_in_sram = NULL;
1860
1861	dev_dbg(host->dev, "%s: cmd = 0x%02x, col = 0x%08x, page = 0x%08x\n",
1862	     __func__, command, column, page_addr);
1863
1864	switch (command) {
1865	case NAND_CMD_RESET:
1866		nfc_addr_cmd = cmd1 | acycle | csid | dataen | nfcwr;
1867		nfc_send_command(host, nfc_addr_cmd, addr1234, cycle0);
1868		udelay(chip->chip_delay);
1869
1870		nfc_nand_command(mtd, NAND_CMD_STATUS, -1, -1);
1871		timeout = jiffies + msecs_to_jiffies(NFC_TIME_OUT_MS);
1872		while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) {
1873			if (time_after(jiffies, timeout)) {
1874				dev_err(host->dev,
1875					"Time out to wait status ready!\n");
1876				break;
1877			}
1878		}
1879		return;
1880	case NAND_CMD_STATUS:
1881		do_addr = false;
1882		break;
1883	case NAND_CMD_PARAM:
1884	case NAND_CMD_READID:
1885		do_addr = false;
1886		acycle = NFCADDR_CMD_ACYCLE_1;
1887		if (column != -1)
1888			addr1234 = column;
1889		break;
1890	case NAND_CMD_RNDOUT:
1891		cmd2 = NAND_CMD_RNDOUTSTART << NFCADDR_CMD_CMD2_BIT_POS;
1892		vcmd2 = NFCADDR_CMD_VCMD2;
1893		break;
1894	case NAND_CMD_READ0:
1895	case NAND_CMD_READOOB:
1896		if (command == NAND_CMD_READOOB) {
1897			column += mtd->writesize;
1898			command = NAND_CMD_READ0; /* only READ0 is valid */
1899			cmd1 = command << NFCADDR_CMD_CMD1_BIT_POS;
1900		}
1901		if (host->nfc->use_nfc_sram) {
1902			/* Enable Data transfer to sram */
1903			dataen = NFCADDR_CMD_DATAEN;
1904
1905			/* Need enable PMECC now, since NFC will transfer
1906			 * data in bus after sending nfc read command.
1907			 */
1908			if (chip->ecc.mode == NAND_ECC_HW && host->has_pmecc)
1909				pmecc_enable(host, NAND_ECC_READ);
1910		}
1911
1912		cmd2 = NAND_CMD_READSTART << NFCADDR_CMD_CMD2_BIT_POS;
1913		vcmd2 = NFCADDR_CMD_VCMD2;
1914		break;
1915	/* For prgramming command, the cmd need set to write enable */
1916	case NAND_CMD_PAGEPROG:
1917	case NAND_CMD_SEQIN:
1918	case NAND_CMD_RNDIN:
1919		nfcwr = NFCADDR_CMD_NFCWR;
1920		if (host->nfc->will_write_sram && command == NAND_CMD_SEQIN)
1921			dataen = NFCADDR_CMD_DATAEN;
1922		break;
1923	default:
1924		break;
1925	}
1926
1927	if (do_addr)
1928		acycle = nfc_make_addr(mtd, command, column, page_addr,
1929				&addr1234, &cycle0);
1930
1931	nfc_addr_cmd = cmd1 | cmd2 | vcmd2 | acycle | csid | dataen | nfcwr;
1932	nfc_send_command(host, nfc_addr_cmd, addr1234, cycle0);
1933
1934	/*
1935	 * Program and erase have their own busy handlers status, sequential
1936	 * in, and deplete1 need no delay.
1937	 */
1938	switch (command) {
1939	case NAND_CMD_CACHEDPROG:
1940	case NAND_CMD_PAGEPROG:
1941	case NAND_CMD_ERASE1:
1942	case NAND_CMD_ERASE2:
1943	case NAND_CMD_RNDIN:
1944	case NAND_CMD_STATUS:
1945	case NAND_CMD_RNDOUT:
1946	case NAND_CMD_SEQIN:
1947	case NAND_CMD_READID:
1948		return;
1949
1950	case NAND_CMD_READ0:
1951		if (dataen == NFCADDR_CMD_DATAEN) {
1952			host->nfc->data_in_sram = host->nfc->sram_bank0 +
1953				nfc_get_sram_off(host);
1954			return;
1955		}
1956		/* fall through */
1957	default:
1958		nfc_prepare_interrupt(host, NFC_SR_RB_EDGE);
1959		nfc_wait_interrupt(host, NFC_SR_RB_EDGE);
1960	}
1961}
1962
1963static int nfc_sram_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1964			uint32_t offset, int data_len, const uint8_t *buf,
1965			int oob_required, int page, int cached, int raw)
1966{
1967	int cfg, len;
1968	int status = 0;
1969	struct atmel_nand_host *host = chip->priv;
1970	void *sram = host->nfc->sram_bank0 + nfc_get_sram_off(host);
1971
1972	/* Subpage write is not supported */
1973	if (offset || (data_len < mtd->writesize))
1974		return -EINVAL;
1975
1976	len = mtd->writesize;
1977	/* Copy page data to sram that will write to nand via NFC */
1978	if (use_dma) {
1979		if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) != 0)
1980			/* Fall back to use cpu copy */
1981			memcpy(sram, buf, len);
1982	} else {
1983		memcpy(sram, buf, len);
1984	}
1985
1986	cfg = nfc_readl(host->nfc->hsmc_regs, CFG);
1987	if (unlikely(raw) && oob_required) {
1988		memcpy(sram + len, chip->oob_poi, mtd->oobsize);
1989		len += mtd->oobsize;
1990		nfc_writel(host->nfc->hsmc_regs, CFG, cfg | NFC_CFG_WSPARE);
1991	} else {
1992		nfc_writel(host->nfc->hsmc_regs, CFG, cfg & ~NFC_CFG_WSPARE);
1993	}
1994
1995	if (chip->ecc.mode == NAND_ECC_HW && host->has_pmecc)
1996		/*
1997		 * When use NFC sram, need set up PMECC before send
1998		 * NAND_CMD_SEQIN command. Since when the nand command
1999		 * is sent, nfc will do transfer from sram and nand.
2000		 */
2001		pmecc_enable(host, NAND_ECC_WRITE);
2002
2003	host->nfc->will_write_sram = true;
2004	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
2005	host->nfc->will_write_sram = false;
2006
2007	if (likely(!raw))
2008		/* Need to write ecc into oob */
2009		status = chip->ecc.write_page(mtd, chip, buf, oob_required,
2010					      page);
2011
2012	if (status < 0)
2013		return status;
2014
2015	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2016	status = chip->waitfunc(mtd, chip);
2017
2018	if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2019		status = chip->errstat(mtd, chip, FL_WRITING, status, page);
2020
2021	if (status & NAND_STATUS_FAIL)
2022		return -EIO;
2023
2024	return 0;
2025}
2026
2027static int nfc_sram_init(struct mtd_info *mtd)
2028{
2029	struct nand_chip *chip = mtd->priv;
2030	struct atmel_nand_host *host = chip->priv;
2031	int res = 0;
2032
2033	/* Initialize the NFC CFG register */
2034	unsigned int cfg_nfc = 0;
2035
2036	/* set page size and oob layout */
2037	switch (mtd->writesize) {
2038	case 512:
2039		cfg_nfc = NFC_CFG_PAGESIZE_512;
2040		break;
2041	case 1024:
2042		cfg_nfc = NFC_CFG_PAGESIZE_1024;
2043		break;
2044	case 2048:
2045		cfg_nfc = NFC_CFG_PAGESIZE_2048;
2046		break;
2047	case 4096:
2048		cfg_nfc = NFC_CFG_PAGESIZE_4096;
2049		break;
2050	case 8192:
2051		cfg_nfc = NFC_CFG_PAGESIZE_8192;
2052		break;
2053	default:
2054		dev_err(host->dev, "Unsupported page size for NFC.\n");
2055		res = -ENXIO;
2056		return res;
2057	}
2058
2059	/* oob bytes size = (NFCSPARESIZE + 1) * 4
2060	 * Max support spare size is 512 bytes. */
2061	cfg_nfc |= (((mtd->oobsize / 4) - 1) << NFC_CFG_NFC_SPARESIZE_BIT_POS
2062		& NFC_CFG_NFC_SPARESIZE);
2063	/* default set a max timeout */
2064	cfg_nfc |= NFC_CFG_RSPARE |
2065			NFC_CFG_NFC_DTOCYC | NFC_CFG_NFC_DTOMUL;
2066
2067	nfc_writel(host->nfc->hsmc_regs, CFG, cfg_nfc);
2068
2069	host->nfc->will_write_sram = false;
2070	nfc_set_sram_bank(host, 0);
2071
2072	/* Use Write page with NFC SRAM only for PMECC or ECC NONE. */
2073	if (host->nfc->write_by_sram) {
2074		if ((chip->ecc.mode == NAND_ECC_HW && host->has_pmecc) ||
2075				chip->ecc.mode == NAND_ECC_NONE)
2076			chip->write_page = nfc_sram_write_page;
2077		else
2078			host->nfc->write_by_sram = false;
2079	}
2080
2081	dev_info(host->dev, "Using NFC Sram read %s\n",
2082			host->nfc->write_by_sram ? "and write" : "");
2083	return 0;
2084}
2085
2086static struct platform_driver atmel_nand_nfc_driver;
2087/*
2088 * Probe for the NAND device.
2089 */
2090static int atmel_nand_probe(struct platform_device *pdev)
2091{
2092	struct atmel_nand_host *host;
2093	struct mtd_info *mtd;
2094	struct nand_chip *nand_chip;
2095	struct resource *mem;
2096	struct mtd_part_parser_data ppdata = {};
2097	int res, irq;
2098
2099	/* Allocate memory for the device structure (and zero it) */
2100	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
2101	if (!host)
2102		return -ENOMEM;
2103
2104	res = platform_driver_register(&atmel_nand_nfc_driver);
2105	if (res)
2106		dev_err(&pdev->dev, "atmel_nand: can't register NFC driver\n");
2107
2108	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2109	host->io_base = devm_ioremap_resource(&pdev->dev, mem);
2110	if (IS_ERR(host->io_base)) {
2111		res = PTR_ERR(host->io_base);
2112		goto err_nand_ioremap;
2113	}
2114	host->io_phys = (dma_addr_t)mem->start;
2115
2116	mtd = &host->mtd;
2117	nand_chip = &host->nand_chip;
2118	host->dev = &pdev->dev;
2119	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
2120		/* Only when CONFIG_OF is enabled of_node can be parsed */
2121		res = atmel_of_init_port(host, pdev->dev.of_node);
2122		if (res)
2123			goto err_nand_ioremap;
2124	} else {
2125		memcpy(&host->board, dev_get_platdata(&pdev->dev),
2126		       sizeof(struct atmel_nand_data));
2127	}
2128
2129	nand_chip->priv = host;		/* link the private data structures */
2130	mtd->priv = nand_chip;
2131	mtd->dev.parent = &pdev->dev;
2132
2133	/* Set address of NAND IO lines */
2134	nand_chip->IO_ADDR_R = host->io_base;
2135	nand_chip->IO_ADDR_W = host->io_base;
2136
2137	if (nand_nfc.is_initialized) {
2138		/* NFC driver is probed and initialized */
2139		host->nfc = &nand_nfc;
2140
2141		nand_chip->select_chip = nfc_select_chip;
2142		nand_chip->dev_ready = nfc_device_ready;
2143		nand_chip->cmdfunc = nfc_nand_command;
2144
2145		/* Initialize the interrupt for NFC */
2146		irq = platform_get_irq(pdev, 0);
2147		if (irq < 0) {
2148			dev_err(host->dev, "Cannot get HSMC irq!\n");
2149			res = irq;
2150			goto err_nand_ioremap;
2151		}
2152
2153		res = devm_request_irq(&pdev->dev, irq, hsmc_interrupt,
2154				0, "hsmc", host);
2155		if (res) {
2156			dev_err(&pdev->dev, "Unable to request HSMC irq %d\n",
2157				irq);
2158			goto err_nand_ioremap;
2159		}
2160	} else {
2161		res = atmel_nand_set_enable_ready_pins(mtd);
2162		if (res)
2163			goto err_nand_ioremap;
2164
2165		nand_chip->cmd_ctrl = atmel_nand_cmd_ctrl;
2166	}
2167
2168	nand_chip->ecc.mode = host->board.ecc_mode;
2169	nand_chip->chip_delay = 40;		/* 40us command delay time */
2170
2171	if (host->board.bus_width_16)	/* 16-bit bus width */
2172		nand_chip->options |= NAND_BUSWIDTH_16;
2173
2174	nand_chip->read_buf = atmel_read_buf;
2175	nand_chip->write_buf = atmel_write_buf;
2176
2177	platform_set_drvdata(pdev, host);
2178	atmel_nand_enable(host);
2179
2180	if (gpio_is_valid(host->board.det_pin)) {
2181		res = devm_gpio_request(&pdev->dev,
2182				host->board.det_pin, "nand_det");
2183		if (res < 0) {
2184			dev_err(&pdev->dev,
2185				"can't request det gpio %d\n",
2186				host->board.det_pin);
2187			goto err_no_card;
2188		}
2189
2190		res = gpio_direction_input(host->board.det_pin);
2191		if (res < 0) {
2192			dev_err(&pdev->dev,
2193				"can't request input direction det gpio %d\n",
2194				host->board.det_pin);
2195			goto err_no_card;
2196		}
2197
2198		if (gpio_get_value(host->board.det_pin)) {
2199			dev_info(&pdev->dev, "No SmartMedia card inserted.\n");
2200			res = -ENXIO;
2201			goto err_no_card;
2202		}
2203	}
2204
2205	if (host->board.on_flash_bbt || on_flash_bbt) {
2206		dev_info(&pdev->dev, "Use On Flash BBT\n");
2207		nand_chip->bbt_options |= NAND_BBT_USE_FLASH;
2208	}
2209
2210	if (!host->board.has_dma)
2211		use_dma = 0;
2212
2213	if (use_dma) {
2214		dma_cap_mask_t mask;
2215
2216		dma_cap_zero(mask);
2217		dma_cap_set(DMA_MEMCPY, mask);
2218		host->dma_chan = dma_request_channel(mask, NULL, NULL);
2219		if (!host->dma_chan) {
2220			dev_err(host->dev, "Failed to request DMA channel\n");
2221			use_dma = 0;
2222		}
2223	}
2224	if (use_dma)
2225		dev_info(host->dev, "Using %s for DMA transfers.\n",
2226					dma_chan_name(host->dma_chan));
2227	else
2228		dev_info(host->dev, "No DMA support for NAND access.\n");
2229
2230	/* first scan to find the device and get the page size */
2231	if (nand_scan_ident(mtd, 1, NULL)) {
2232		res = -ENXIO;
2233		goto err_scan_ident;
2234	}
2235
2236	if (nand_chip->ecc.mode == NAND_ECC_HW) {
2237		if (host->has_pmecc)
2238			res = atmel_pmecc_nand_init_params(pdev, host);
2239		else
2240			res = atmel_hw_nand_init_params(pdev, host);
2241
2242		if (res != 0)
2243			goto err_hw_ecc;
2244	}
2245
2246	/* initialize the nfc configuration register */
2247	if (host->nfc && host->nfc->use_nfc_sram) {
2248		res = nfc_sram_init(mtd);
2249		if (res) {
2250			host->nfc->use_nfc_sram = false;
2251			dev_err(host->dev, "Disable use nfc sram for data transfer.\n");
2252		}
2253	}
2254
2255	/* second phase scan */
2256	if (nand_scan_tail(mtd)) {
2257		res = -ENXIO;
2258		goto err_scan_tail;
2259	}
2260
2261	mtd->name = "atmel_nand";
2262	ppdata.of_node = pdev->dev.of_node;
2263	res = mtd_device_parse_register(mtd, NULL, &ppdata,
2264			host->board.parts, host->board.num_parts);
2265	if (!res)
2266		return res;
2267
2268err_scan_tail:
2269	if (host->has_pmecc && host->nand_chip.ecc.mode == NAND_ECC_HW)
2270		pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
2271err_hw_ecc:
2272err_scan_ident:
2273err_no_card:
2274	atmel_nand_disable(host);
2275	if (host->dma_chan)
2276		dma_release_channel(host->dma_chan);
2277err_nand_ioremap:
2278	return res;
2279}
2280
2281/*
2282 * Remove a NAND device.
2283 */
2284static int atmel_nand_remove(struct platform_device *pdev)
2285{
2286	struct atmel_nand_host *host = platform_get_drvdata(pdev);
2287	struct mtd_info *mtd = &host->mtd;
2288
2289	nand_release(mtd);
2290
2291	atmel_nand_disable(host);
2292
2293	if (host->has_pmecc && host->nand_chip.ecc.mode == NAND_ECC_HW) {
2294		pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
2295		pmerrloc_writel(host->pmerrloc_base, ELDIS,
2296				PMERRLOC_DISABLE);
2297	}
2298
2299	if (host->dma_chan)
2300		dma_release_channel(host->dma_chan);
2301
2302	platform_driver_unregister(&atmel_nand_nfc_driver);
2303
2304	return 0;
2305}
2306
2307static struct atmel_nand_caps at91rm9200_caps = {
2308	.pmecc_correct_erase_page = false,
2309};
2310
2311static struct atmel_nand_caps sama5d4_caps = {
2312	.pmecc_correct_erase_page = true,
2313};
2314
2315static const struct of_device_id atmel_nand_dt_ids[] = {
2316	{ .compatible = "atmel,at91rm9200-nand", .data = &at91rm9200_caps },
2317	{ .compatible = "atmel,sama5d4-nand", .data = &sama5d4_caps },
2318	{ /* sentinel */ }
2319};
2320
2321MODULE_DEVICE_TABLE(of, atmel_nand_dt_ids);
2322
2323static int atmel_nand_nfc_probe(struct platform_device *pdev)
2324{
2325	struct atmel_nfc *nfc = &nand_nfc;
2326	struct resource *nfc_cmd_regs, *nfc_hsmc_regs, *nfc_sram;
2327	int ret;
2328
2329	nfc_cmd_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2330	nfc->base_cmd_regs = devm_ioremap_resource(&pdev->dev, nfc_cmd_regs);
2331	if (IS_ERR(nfc->base_cmd_regs))
2332		return PTR_ERR(nfc->base_cmd_regs);
2333
2334	nfc_hsmc_regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
2335	nfc->hsmc_regs = devm_ioremap_resource(&pdev->dev, nfc_hsmc_regs);
2336	if (IS_ERR(nfc->hsmc_regs))
2337		return PTR_ERR(nfc->hsmc_regs);
2338
2339	nfc_sram = platform_get_resource(pdev, IORESOURCE_MEM, 2);
2340	if (nfc_sram) {
2341		nfc->sram_bank0 = (void * __force)
2342				devm_ioremap_resource(&pdev->dev, nfc_sram);
2343		if (IS_ERR(nfc->sram_bank0)) {
2344			dev_warn(&pdev->dev, "Fail to ioremap the NFC sram with error: %ld. So disable NFC sram.\n",
2345					PTR_ERR(nfc->sram_bank0));
2346		} else {
2347			nfc->use_nfc_sram = true;
2348			nfc->sram_bank0_phys = (dma_addr_t)nfc_sram->start;
2349
2350			if (pdev->dev.of_node)
2351				nfc->write_by_sram = of_property_read_bool(
2352						pdev->dev.of_node,
2353						"atmel,write-by-sram");
2354		}
2355	}
2356
2357	nfc_writel(nfc->hsmc_regs, IDR, 0xffffffff);
2358	nfc_readl(nfc->hsmc_regs, SR);	/* clear the NFC_SR */
2359
2360	nfc->clk = devm_clk_get(&pdev->dev, NULL);
2361	if (!IS_ERR(nfc->clk)) {
2362		ret = clk_prepare_enable(nfc->clk);
2363		if (ret)
2364			return ret;
2365	} else {
2366		dev_warn(&pdev->dev, "NFC clock missing, update your Device Tree");
2367	}
2368
2369	nfc->is_initialized = true;
2370	dev_info(&pdev->dev, "NFC is probed.\n");
2371
2372	return 0;
2373}
2374
2375static int atmel_nand_nfc_remove(struct platform_device *pdev)
2376{
2377	struct atmel_nfc *nfc = &nand_nfc;
2378
2379	if (!IS_ERR(nfc->clk))
2380		clk_disable_unprepare(nfc->clk);
2381
2382	return 0;
2383}
2384
2385static const struct of_device_id atmel_nand_nfc_match[] = {
2386	{ .compatible = "atmel,sama5d3-nfc" },
2387	{ /* sentinel */ }
2388};
2389MODULE_DEVICE_TABLE(of, atmel_nand_nfc_match);
2390
2391static struct platform_driver atmel_nand_nfc_driver = {
2392	.driver = {
2393		.name = "atmel_nand_nfc",
2394		.of_match_table = of_match_ptr(atmel_nand_nfc_match),
2395	},
2396	.probe = atmel_nand_nfc_probe,
2397	.remove = atmel_nand_nfc_remove,
2398};
2399
2400static struct platform_driver atmel_nand_driver = {
2401	.probe		= atmel_nand_probe,
2402	.remove		= atmel_nand_remove,
2403	.driver		= {
2404		.name	= "atmel_nand",
2405		.of_match_table	= of_match_ptr(atmel_nand_dt_ids),
2406	},
2407};
2408
2409module_platform_driver(atmel_nand_driver);
2410
2411MODULE_LICENSE("GPL");
2412MODULE_AUTHOR("Rick Bronson");
2413MODULE_DESCRIPTION("NAND/SmartMedia driver for AT91 / AVR32");
2414MODULE_ALIAS("platform:atmel_nand");
2415