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{
959	struct atmel_nand_host *host = chip->priv;
960	uint32_t *eccpos = chip->ecc.layout->eccpos;
961	int i, j;
962	unsigned long end_time;
963
964	if (!host->nfc || !host->nfc->write_by_sram) {
965		pmecc_enable(host, NAND_ECC_WRITE);
966		chip->write_buf(mtd, (u8 *)buf, mtd->writesize);
967	}
968
969	end_time = jiffies + msecs_to_jiffies(PMECC_MAX_TIMEOUT_MS);
970	while ((pmecc_readl_relaxed(host->ecc, SR) & PMECC_SR_BUSY)) {
971		if (unlikely(time_after(jiffies, end_time))) {
972			dev_err(host->dev, "PMECC: Timeout to get ECC value.\n");
973			return -EIO;
974		}
975		cpu_relax();
976	}
977
978	for (i = 0; i < chip->ecc.steps; i++) {
979		for (j = 0; j < chip->ecc.bytes; j++) {
980			int pos;
981
982			pos = i * chip->ecc.bytes + j;
983			chip->oob_poi[eccpos[pos]] =
984				pmecc_readb_ecc_relaxed(host->ecc, i, j);
985		}
986	}
987	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
988
989	return 0;
990}
991
992static void atmel_pmecc_core_init(struct mtd_info *mtd)
993{
994	struct nand_chip *nand_chip = mtd->priv;
995	struct atmel_nand_host *host = nand_chip->priv;
996	uint32_t val = 0;
997	struct nand_ecclayout *ecc_layout;
998
999	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_RST);
1000	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
1001
1002	switch (host->pmecc_corr_cap) {
1003	case 2:
1004		val = PMECC_CFG_BCH_ERR2;
1005		break;
1006	case 4:
1007		val = PMECC_CFG_BCH_ERR4;
1008		break;
1009	case 8:
1010		val = PMECC_CFG_BCH_ERR8;
1011		break;
1012	case 12:
1013		val = PMECC_CFG_BCH_ERR12;
1014		break;
1015	case 24:
1016		val = PMECC_CFG_BCH_ERR24;
1017		break;
1018	}
1019
1020	if (host->pmecc_sector_size == 512)
1021		val |= PMECC_CFG_SECTOR512;
1022	else if (host->pmecc_sector_size == 1024)
1023		val |= PMECC_CFG_SECTOR1024;
1024
1025	switch (nand_chip->ecc.steps) {
1026	case 1:
1027		val |= PMECC_CFG_PAGE_1SECTOR;
1028		break;
1029	case 2:
1030		val |= PMECC_CFG_PAGE_2SECTORS;
1031		break;
1032	case 4:
1033		val |= PMECC_CFG_PAGE_4SECTORS;
1034		break;
1035	case 8:
1036		val |= PMECC_CFG_PAGE_8SECTORS;
1037		break;
1038	}
1039
1040	val |= (PMECC_CFG_READ_OP | PMECC_CFG_SPARE_DISABLE
1041		| PMECC_CFG_AUTO_DISABLE);
1042	pmecc_writel(host->ecc, CFG, val);
1043
1044	ecc_layout = nand_chip->ecc.layout;
1045	pmecc_writel(host->ecc, SAREA, mtd->oobsize - 1);
1046	pmecc_writel(host->ecc, SADDR, ecc_layout->eccpos[0]);
1047	pmecc_writel(host->ecc, EADDR,
1048			ecc_layout->eccpos[ecc_layout->eccbytes - 1]);
1049	/* See datasheet about PMECC Clock Control Register */
1050	pmecc_writel(host->ecc, CLK, 2);
1051	pmecc_writel(host->ecc, IDR, 0xff);
1052	pmecc_writel(host->ecc, CTRL, PMECC_CTRL_ENABLE);
1053}
1054
1055/*
1056 * Get minimum ecc requirements from NAND.
1057 * If pmecc-cap, pmecc-sector-size in DTS are not specified, this function
1058 * will set them according to minimum ecc requirement. Otherwise, use the
1059 * value in DTS file.
1060 * return 0 if success. otherwise return error code.
1061 */
1062static int pmecc_choose_ecc(struct atmel_nand_host *host,
1063		int *cap, int *sector_size)
1064{
1065	/* Get minimum ECC requirements */
1066	if (host->nand_chip.ecc_strength_ds) {
1067		*cap = host->nand_chip.ecc_strength_ds;
1068		*sector_size = host->nand_chip.ecc_step_ds;
1069		dev_info(host->dev, "minimum ECC: %d bits in %d bytes\n",
1070				*cap, *sector_size);
1071	} else {
1072		*cap = 2;
1073		*sector_size = 512;
1074		dev_info(host->dev, "can't detect min. ECC, assume 2 bits in 512 bytes\n");
1075	}
1076
1077	/* If device tree doesn't specify, use NAND's minimum ECC parameters */
1078	if (host->pmecc_corr_cap == 0) {
1079		/* use the most fitable ecc bits (the near bigger one ) */
1080		if (*cap <= 2)
1081			host->pmecc_corr_cap = 2;
1082		else if (*cap <= 4)
1083			host->pmecc_corr_cap = 4;
1084		else if (*cap <= 8)
1085			host->pmecc_corr_cap = 8;
1086		else if (*cap <= 12)
1087			host->pmecc_corr_cap = 12;
1088		else if (*cap <= 24)
1089			host->pmecc_corr_cap = 24;
1090		else
1091			return -EINVAL;
1092	}
1093	if (host->pmecc_sector_size == 0) {
1094		/* use the most fitable sector size (the near smaller one ) */
1095		if (*sector_size >= 1024)
1096			host->pmecc_sector_size = 1024;
1097		else if (*sector_size >= 512)
1098			host->pmecc_sector_size = 512;
1099		else
1100			return -EINVAL;
1101	}
1102	return 0;
1103}
1104
1105static inline int deg(unsigned int poly)
1106{
1107	/* polynomial degree is the most-significant bit index */
1108	return fls(poly) - 1;
1109}
1110
1111static int build_gf_tables(int mm, unsigned int poly,
1112		int16_t *index_of, int16_t *alpha_to)
1113{
1114	unsigned int i, x = 1;
1115	const unsigned int k = 1 << deg(poly);
1116	unsigned int nn = (1 << mm) - 1;
1117
1118	/* primitive polynomial must be of degree m */
1119	if (k != (1u << mm))
1120		return -EINVAL;
1121
1122	for (i = 0; i < nn; i++) {
1123		alpha_to[i] = x;
1124		index_of[x] = i;
1125		if (i && (x == 1))
1126			/* polynomial is not primitive (a^i=1 with 0<i<2^m-1) */
1127			return -EINVAL;
1128		x <<= 1;
1129		if (x & k)
1130			x ^= poly;
1131	}
1132	alpha_to[nn] = 1;
1133	index_of[0] = 0;
1134
1135	return 0;
1136}
1137
1138static uint16_t *create_lookup_table(struct device *dev, int sector_size)
1139{
1140	int degree = (sector_size == 512) ?
1141			PMECC_GF_DIMENSION_13 :
1142			PMECC_GF_DIMENSION_14;
1143	unsigned int poly = (sector_size == 512) ?
1144			PMECC_GF_13_PRIMITIVE_POLY :
1145			PMECC_GF_14_PRIMITIVE_POLY;
1146	int table_size = (sector_size == 512) ?
1147			PMECC_LOOKUP_TABLE_SIZE_512 :
1148			PMECC_LOOKUP_TABLE_SIZE_1024;
1149
1150	int16_t *addr = devm_kzalloc(dev, 2 * table_size * sizeof(uint16_t),
1151			GFP_KERNEL);
1152	if (addr && build_gf_tables(degree, poly, addr, addr + table_size))
1153		return NULL;
1154
1155	return addr;
1156}
1157
1158static int atmel_pmecc_nand_init_params(struct platform_device *pdev,
1159					 struct atmel_nand_host *host)
1160{
1161	struct mtd_info *mtd = &host->mtd;
1162	struct nand_chip *nand_chip = &host->nand_chip;
1163	struct resource *regs, *regs_pmerr, *regs_rom;
1164	uint16_t *galois_table;
1165	int cap, sector_size, err_no;
1166
1167	err_no = pmecc_choose_ecc(host, &cap, &sector_size);
1168	if (err_no) {
1169		dev_err(host->dev, "The NAND flash's ECC requirement are not support!");
1170		return err_no;
1171	}
1172
1173	if (cap > host->pmecc_corr_cap ||
1174			sector_size != host->pmecc_sector_size)
1175		dev_info(host->dev, "WARNING: Be Caution! Using different PMECC parameters from Nand ONFI ECC reqirement.\n");
1176
1177	cap = host->pmecc_corr_cap;
1178	sector_size = host->pmecc_sector_size;
1179	host->pmecc_lookup_table_offset = (sector_size == 512) ?
1180			host->pmecc_lookup_table_offset_512 :
1181			host->pmecc_lookup_table_offset_1024;
1182
1183	dev_info(host->dev, "Initialize PMECC params, cap: %d, sector: %d\n",
1184		 cap, sector_size);
1185
1186	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1187	if (!regs) {
1188		dev_warn(host->dev,
1189			"Can't get I/O resource regs for PMECC controller, rolling back on software ECC\n");
1190		nand_chip->ecc.mode = NAND_ECC_SOFT;
1191		return 0;
1192	}
1193
1194	host->ecc = devm_ioremap_resource(&pdev->dev, regs);
1195	if (IS_ERR(host->ecc)) {
1196		err_no = PTR_ERR(host->ecc);
1197		goto err;
1198	}
1199
1200	regs_pmerr = platform_get_resource(pdev, IORESOURCE_MEM, 2);
1201	host->pmerrloc_base = devm_ioremap_resource(&pdev->dev, regs_pmerr);
1202	if (IS_ERR(host->pmerrloc_base)) {
1203		err_no = PTR_ERR(host->pmerrloc_base);
1204		goto err;
1205	}
1206
1207	if (!host->has_no_lookup_table) {
1208		regs_rom = platform_get_resource(pdev, IORESOURCE_MEM, 3);
1209		host->pmecc_rom_base = devm_ioremap_resource(&pdev->dev,
1210								regs_rom);
1211		if (IS_ERR(host->pmecc_rom_base)) {
1212			dev_err(host->dev, "Can not get I/O resource for ROM, will build a lookup table in runtime!\n");
1213			host->has_no_lookup_table = true;
1214		}
1215	}
1216
1217	if (host->has_no_lookup_table) {
1218		/* Build the look-up table in runtime */
1219		galois_table = create_lookup_table(host->dev, sector_size);
1220		if (!galois_table) {
1221			dev_err(host->dev, "Failed to build a lookup table in runtime!\n");
1222			err_no = -EINVAL;
1223			goto err;
1224		}
1225
1226		host->pmecc_rom_base = (void __iomem *)galois_table;
1227		host->pmecc_lookup_table_offset = 0;
1228	}
1229
1230	nand_chip->ecc.size = sector_size;
1231
1232	/* set ECC page size and oob layout */
1233	switch (mtd->writesize) {
1234	case 512:
1235	case 1024:
1236	case 2048:
1237	case 4096:
1238	case 8192:
1239		if (sector_size > mtd->writesize) {
1240			dev_err(host->dev, "pmecc sector size is bigger than the page size!\n");
1241			err_no = -EINVAL;
1242			goto err;
1243		}
1244
1245		host->pmecc_degree = (sector_size == 512) ?
1246			PMECC_GF_DIMENSION_13 : PMECC_GF_DIMENSION_14;
1247		host->pmecc_cw_len = (1 << host->pmecc_degree) - 1;
1248		host->pmecc_alpha_to = pmecc_get_alpha_to(host);
1249		host->pmecc_index_of = host->pmecc_rom_base +
1250			host->pmecc_lookup_table_offset;
1251
1252		nand_chip->ecc.strength = cap;
1253		nand_chip->ecc.bytes = pmecc_get_ecc_bytes(cap, sector_size);
1254		nand_chip->ecc.steps = mtd->writesize / sector_size;
1255		nand_chip->ecc.total = nand_chip->ecc.bytes *
1256			nand_chip->ecc.steps;
1257		if (nand_chip->ecc.total >
1258				mtd->oobsize - PMECC_OOB_RESERVED_BYTES) {
1259			dev_err(host->dev, "No room for ECC bytes\n");
1260			err_no = -EINVAL;
1261			goto err;
1262		}
1263		pmecc_config_ecc_layout(&atmel_pmecc_oobinfo,
1264					mtd->oobsize,
1265					nand_chip->ecc.total);
1266
1267		nand_chip->ecc.layout = &atmel_pmecc_oobinfo;
1268		break;
1269	default:
1270		dev_warn(host->dev,
1271			"Unsupported page size for PMECC, use Software ECC\n");
1272		/* page size not handled by HW ECC */
1273		/* switching back to soft ECC */
1274		nand_chip->ecc.mode = NAND_ECC_SOFT;
1275		return 0;
1276	}
1277
1278	/* Allocate data for PMECC computation */
1279	err_no = pmecc_data_alloc(host);
1280	if (err_no) {
1281		dev_err(host->dev,
1282				"Cannot allocate memory for PMECC computation!\n");
1283		goto err;
1284	}
1285
1286	nand_chip->options |= NAND_NO_SUBPAGE_WRITE;
1287	nand_chip->ecc.read_page = atmel_nand_pmecc_read_page;
1288	nand_chip->ecc.write_page = atmel_nand_pmecc_write_page;
1289
1290	atmel_pmecc_core_init(mtd);
1291
1292	return 0;
1293
1294err:
1295	return err_no;
1296}
1297
1298/*
1299 * Calculate HW ECC
1300 *
1301 * function called after a write
1302 *
1303 * mtd:        MTD block structure
1304 * dat:        raw data (unused)
1305 * ecc_code:   buffer for ECC
1306 */
1307static int atmel_nand_calculate(struct mtd_info *mtd,
1308		const u_char *dat, unsigned char *ecc_code)
1309{
1310	struct nand_chip *nand_chip = mtd->priv;
1311	struct atmel_nand_host *host = nand_chip->priv;
1312	unsigned int ecc_value;
1313
1314	/* get the first 2 ECC bytes */
1315	ecc_value = ecc_readl(host->ecc, PR);
1316
1317	ecc_code[0] = ecc_value & 0xFF;
1318	ecc_code[1] = (ecc_value >> 8) & 0xFF;
1319
1320	/* get the last 2 ECC bytes */
1321	ecc_value = ecc_readl(host->ecc, NPR) & ATMEL_ECC_NPARITY;
1322
1323	ecc_code[2] = ecc_value & 0xFF;
1324	ecc_code[3] = (ecc_value >> 8) & 0xFF;
1325
1326	return 0;
1327}
1328
1329/*
1330 * HW ECC read page function
1331 *
1332 * mtd:        mtd info structure
1333 * chip:       nand chip info structure
1334 * buf:        buffer to store read data
1335 * oob_required:    caller expects OOB data read to chip->oob_poi
1336 */
1337static int atmel_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
1338				uint8_t *buf, int oob_required, int page)
1339{
1340	int eccsize = chip->ecc.size;
1341	int eccbytes = chip->ecc.bytes;
1342	uint32_t *eccpos = chip->ecc.layout->eccpos;
1343	uint8_t *p = buf;
1344	uint8_t *oob = chip->oob_poi;
1345	uint8_t *ecc_pos;
1346	int stat;
1347	unsigned int max_bitflips = 0;
1348
1349	/*
1350	 * Errata: ALE is incorrectly wired up to the ECC controller
1351	 * on the AP7000, so it will include the address cycles in the
1352	 * ECC calculation.
1353	 *
1354	 * Workaround: Reset the parity registers before reading the
1355	 * actual data.
1356	 */
1357	struct atmel_nand_host *host = chip->priv;
1358	if (host->board.need_reset_workaround)
1359		ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
1360
1361	/* read the page */
1362	chip->read_buf(mtd, p, eccsize);
1363
1364	/* move to ECC position if needed */
1365	if (eccpos[0] != 0) {
1366		/* This only works on large pages
1367		 * because the ECC controller waits for
1368		 * NAND_CMD_RNDOUTSTART after the
1369		 * NAND_CMD_RNDOUT.
1370		 * anyway, for small pages, the eccpos[0] == 0
1371		 */
1372		chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
1373				mtd->writesize + eccpos[0], -1);
1374	}
1375
1376	/* the ECC controller needs to read the ECC just after the data */
1377	ecc_pos = oob + eccpos[0];
1378	chip->read_buf(mtd, ecc_pos, eccbytes);
1379
1380	/* check if there's an error */
1381	stat = chip->ecc.correct(mtd, p, oob, NULL);
1382
1383	if (stat < 0) {
1384		mtd->ecc_stats.failed++;
1385	} else {
1386		mtd->ecc_stats.corrected += stat;
1387		max_bitflips = max_t(unsigned int, max_bitflips, stat);
1388	}
1389
1390	/* get back to oob start (end of page) */
1391	chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
1392
1393	/* read the oob */
1394	chip->read_buf(mtd, oob, mtd->oobsize);
1395
1396	return max_bitflips;
1397}
1398
1399/*
1400 * HW ECC Correction
1401 *
1402 * function called after a read
1403 *
1404 * mtd:        MTD block structure
1405 * dat:        raw data read from the chip
1406 * read_ecc:   ECC from the chip (unused)
1407 * isnull:     unused
1408 *
1409 * Detect and correct a 1 bit error for a page
1410 */
1411static int atmel_nand_correct(struct mtd_info *mtd, u_char *dat,
1412		u_char *read_ecc, u_char *isnull)
1413{
1414	struct nand_chip *nand_chip = mtd->priv;
1415	struct atmel_nand_host *host = nand_chip->priv;
1416	unsigned int ecc_status;
1417	unsigned int ecc_word, ecc_bit;
1418
1419	/* get the status from the Status Register */
1420	ecc_status = ecc_readl(host->ecc, SR);
1421
1422	/* if there's no error */
1423	if (likely(!(ecc_status & ATMEL_ECC_RECERR)))
1424		return 0;
1425
1426	/* get error bit offset (4 bits) */
1427	ecc_bit = ecc_readl(host->ecc, PR) & ATMEL_ECC_BITADDR;
1428	/* get word address (12 bits) */
1429	ecc_word = ecc_readl(host->ecc, PR) & ATMEL_ECC_WORDADDR;
1430	ecc_word >>= 4;
1431
1432	/* if there are multiple errors */
1433	if (ecc_status & ATMEL_ECC_MULERR) {
1434		/* check if it is a freshly erased block
1435		 * (filled with 0xff) */
1436		if ((ecc_bit == ATMEL_ECC_BITADDR)
1437				&& (ecc_word == (ATMEL_ECC_WORDADDR >> 4))) {
1438			/* the block has just been erased, return OK */
1439			return 0;
1440		}
1441		/* it doesn't seems to be a freshly
1442		 * erased block.
1443		 * We can't correct so many errors */
1444		dev_dbg(host->dev, "atmel_nand : multiple errors detected."
1445				" Unable to correct.\n");
1446		return -EIO;
1447	}
1448
1449	/* if there's a single bit error : we can correct it */
1450	if (ecc_status & ATMEL_ECC_ECCERR) {
1451		/* there's nothing much to do here.
1452		 * the bit error is on the ECC itself.
1453		 */
1454		dev_dbg(host->dev, "atmel_nand : one bit error on ECC code."
1455				" Nothing to correct\n");
1456		return 0;
1457	}
1458
1459	dev_dbg(host->dev, "atmel_nand : one bit error on data."
1460			" (word offset in the page :"
1461			" 0x%x bit offset : 0x%x)\n",
1462			ecc_word, ecc_bit);
1463	/* correct the error */
1464	if (nand_chip->options & NAND_BUSWIDTH_16) {
1465		/* 16 bits words */
1466		((unsigned short *) dat)[ecc_word] ^= (1 << ecc_bit);
1467	} else {
1468		/* 8 bits words */
1469		dat[ecc_word] ^= (1 << ecc_bit);
1470	}
1471	dev_dbg(host->dev, "atmel_nand : error corrected\n");
1472	return 1;
1473}
1474
1475/*
1476 * Enable HW ECC : unused on most chips
1477 */
1478static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
1479{
1480	struct nand_chip *nand_chip = mtd->priv;
1481	struct atmel_nand_host *host = nand_chip->priv;
1482
1483	if (host->board.need_reset_workaround)
1484		ecc_writel(host->ecc, CR, ATMEL_ECC_RST);
1485}
1486
1487static const struct of_device_id atmel_nand_dt_ids[];
1488
1489static int atmel_of_init_port(struct atmel_nand_host *host,
1490			      struct device_node *np)
1491{
1492	u32 val;
1493	u32 offset[2];
1494	int ecc_mode;
1495	struct atmel_nand_data *board = &host->board;
1496	enum of_gpio_flags flags = 0;
1497
1498	host->caps = (struct atmel_nand_caps *)
1499		of_match_device(atmel_nand_dt_ids, host->dev)->data;
1500
1501	if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) {
1502		if (val >= 32) {
1503			dev_err(host->dev, "invalid addr-offset %u\n", val);
1504			return -EINVAL;
1505		}
1506		board->ale = val;
1507	}
1508
1509	if (of_property_read_u32(np, "atmel,nand-cmd-offset", &val) == 0) {
1510		if (val >= 32) {
1511			dev_err(host->dev, "invalid cmd-offset %u\n", val);
1512			return -EINVAL;
1513		}
1514		board->cle = val;
1515	}
1516
1517	ecc_mode = of_get_nand_ecc_mode(np);
1518
1519	board->ecc_mode = ecc_mode < 0 ? NAND_ECC_SOFT : ecc_mode;
1520
1521	board->on_flash_bbt = of_get_nand_on_flash_bbt(np);
1522
1523	board->has_dma = of_property_read_bool(np, "atmel,nand-has-dma");
1524
1525	if (of_get_nand_bus_width(np) == 16)
1526		board->bus_width_16 = 1;
1527
1528	board->rdy_pin = of_get_gpio_flags(np, 0, &flags);
1529	board->rdy_pin_active_low = (flags == OF_GPIO_ACTIVE_LOW);
1530
1531	board->enable_pin = of_get_gpio(np, 1);
1532	board->det_pin = of_get_gpio(np, 2);
1533
1534	host->has_pmecc = of_property_read_bool(np, "atmel,has-pmecc");
1535
1536	/* load the nfc driver if there is */
1537	of_platform_populate(np, NULL, NULL, host->dev);
1538
1539	if (!(board->ecc_mode == NAND_ECC_HW) || !host->has_pmecc)
1540		return 0;	/* Not using PMECC */
1541
1542	/* use PMECC, get correction capability, sector size and lookup
1543	 * table offset.
1544	 * If correction bits and sector size are not specified, then find
1545	 * them from NAND ONFI parameters.
1546	 */
1547	if (of_property_read_u32(np, "atmel,pmecc-cap", &val) == 0) {
1548		if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
1549				(val != 24)) {
1550			dev_err(host->dev,
1551				"Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
1552				val);
1553			return -EINVAL;
1554		}
1555		host->pmecc_corr_cap = (u8)val;
1556	}
1557
1558	if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) == 0) {
1559		if ((val != 512) && (val != 1024)) {
1560			dev_err(host->dev,
1561				"Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
1562				val);
1563			return -EINVAL;
1564		}
1565		host->pmecc_sector_size = (u16)val;
1566	}
1567
1568	if (of_property_read_u32_array(np, "atmel,pmecc-lookup-table-offset",
1569			offset, 2) != 0) {
1570		dev_err(host->dev, "Cannot get PMECC lookup table offset, will build a lookup table in runtime.\n");
1571		host->has_no_lookup_table = true;
1572		/* Will build a lookup table and initialize the offset later */
1573		return 0;
1574	}
1575	if (!offset[0] && !offset[1]) {
1576		dev_err(host->dev, "Invalid PMECC lookup table offset\n");
1577		return -EINVAL;
1578	}
1579	host->pmecc_lookup_table_offset_512 = offset[0];
1580	host->pmecc_lookup_table_offset_1024 = offset[1];
1581
1582	return 0;
1583}
1584
1585static int atmel_hw_nand_init_params(struct platform_device *pdev,
1586					 struct atmel_nand_host *host)
1587{
1588	struct mtd_info *mtd = &host->mtd;
1589	struct nand_chip *nand_chip = &host->nand_chip;
1590	struct resource		*regs;
1591
1592	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1593	if (!regs) {
1594		dev_err(host->dev,
1595			"Can't get I/O resource regs, use software ECC\n");
1596		nand_chip->ecc.mode = NAND_ECC_SOFT;
1597		return 0;
1598	}
1599
1600	host->ecc = devm_ioremap_resource(&pdev->dev, regs);
1601	if (IS_ERR(host->ecc))
1602		return PTR_ERR(host->ecc);
1603
1604	/* ECC is calculated for the whole page (1 step) */
1605	nand_chip->ecc.size = mtd->writesize;
1606
1607	/* set ECC page size and oob layout */
1608	switch (mtd->writesize) {
1609	case 512:
1610		nand_chip->ecc.layout = &atmel_oobinfo_small;
1611		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_528);
1612		break;
1613	case 1024:
1614		nand_chip->ecc.layout = &atmel_oobinfo_large;
1615		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_1056);
1616		break;
1617	case 2048:
1618		nand_chip->ecc.layout = &atmel_oobinfo_large;
1619		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_2112);
1620		break;
1621	case 4096:
1622		nand_chip->ecc.layout = &atmel_oobinfo_large;
1623		ecc_writel(host->ecc, MR, ATMEL_ECC_PAGESIZE_4224);
1624		break;
1625	default:
1626		/* page size not handled by HW ECC */
1627		/* switching back to soft ECC */
1628		nand_chip->ecc.mode = NAND_ECC_SOFT;
1629		return 0;
1630	}
1631
1632	/* set up for HW ECC */
1633	nand_chip->ecc.calculate = atmel_nand_calculate;
1634	nand_chip->ecc.correct = atmel_nand_correct;
1635	nand_chip->ecc.hwctl = atmel_nand_hwctl;
1636	nand_chip->ecc.read_page = atmel_nand_read_page;
1637	nand_chip->ecc.bytes = 4;
1638	nand_chip->ecc.strength = 1;
1639
1640	return 0;
1641}
1642
1643static inline u32 nfc_read_status(struct atmel_nand_host *host)
1644{
1645	u32 err_flags = NFC_SR_DTOE | NFC_SR_UNDEF | NFC_SR_AWB | NFC_SR_ASE;
1646	u32 nfc_status = nfc_readl(host->nfc->hsmc_regs, SR);
1647
1648	if (unlikely(nfc_status & err_flags)) {
1649		if (nfc_status & NFC_SR_DTOE)
1650			dev_err(host->dev, "NFC: Waiting Nand R/B Timeout Error\n");
1651		else if (nfc_status & NFC_SR_UNDEF)
1652			dev_err(host->dev, "NFC: Access Undefined Area Error\n");
1653		else if (nfc_status & NFC_SR_AWB)
1654			dev_err(host->dev, "NFC: Access memory While NFC is busy\n");
1655		else if (nfc_status & NFC_SR_ASE)
1656			dev_err(host->dev, "NFC: Access memory Size Error\n");
1657	}
1658
1659	return nfc_status;
1660}
1661
1662/* SMC interrupt service routine */
1663static irqreturn_t hsmc_interrupt(int irq, void *dev_id)
1664{
1665	struct atmel_nand_host *host = dev_id;
1666	u32 status, mask, pending;
1667	irqreturn_t ret = IRQ_NONE;
1668
1669	status = nfc_read_status(host);
1670	mask = nfc_readl(host->nfc->hsmc_regs, IMR);
1671	pending = status & mask;
1672
1673	if (pending & NFC_SR_XFR_DONE) {
1674		complete(&host->nfc->comp_xfer_done);
1675		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_XFR_DONE);
1676		ret = IRQ_HANDLED;
1677	}
1678	if (pending & NFC_SR_RB_EDGE) {
1679		complete(&host->nfc->comp_ready);
1680		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_RB_EDGE);
1681		ret = IRQ_HANDLED;
1682	}
1683	if (pending & NFC_SR_CMD_DONE) {
1684		complete(&host->nfc->comp_cmd_done);
1685		nfc_writel(host->nfc->hsmc_regs, IDR, NFC_SR_CMD_DONE);
1686		ret = IRQ_HANDLED;
1687	}
1688
1689	return ret;
1690}
1691
1692/* NFC(Nand Flash Controller) related functions */
1693static void nfc_prepare_interrupt(struct atmel_nand_host *host, u32 flag)
1694{
1695	if (flag & NFC_SR_XFR_DONE)
1696		init_completion(&host->nfc->comp_xfer_done);
1697
1698	if (flag & NFC_SR_RB_EDGE)
1699		init_completion(&host->nfc->comp_ready);
1700
1701	if (flag & NFC_SR_CMD_DONE)
1702		init_completion(&host->nfc->comp_cmd_done);
1703
1704	/* Enable interrupt that need to wait for */
1705	nfc_writel(host->nfc->hsmc_regs, IER, flag);
1706}
1707
1708static int nfc_wait_interrupt(struct atmel_nand_host *host, u32 flag)
1709{
1710	int i, index = 0;
1711	struct completion *comp[3];	/* Support 3 interrupt completion */
1712
1713	if (flag & NFC_SR_XFR_DONE)
1714		comp[index++] = &host->nfc->comp_xfer_done;
1715
1716	if (flag & NFC_SR_RB_EDGE)
1717		comp[index++] = &host->nfc->comp_ready;
1718
1719	if (flag & NFC_SR_CMD_DONE)
1720		comp[index++] = &host->nfc->comp_cmd_done;
1721
1722	if (index == 0) {
1723		dev_err(host->dev, "Unknown interrupt flag: 0x%08x\n", flag);
1724		return -EINVAL;
1725	}
1726
1727	for (i = 0; i < index; i++) {
1728		if (wait_for_completion_timeout(comp[i],
1729				msecs_to_jiffies(NFC_TIME_OUT_MS)))
1730			continue;	/* wait for next completion */
1731		else
1732			goto err_timeout;
1733	}
1734
1735	return 0;
1736
1737err_timeout:
1738	dev_err(host->dev, "Time out to wait for interrupt: 0x%08x\n", flag);
1739	/* Disable the interrupt as it is not handled by interrupt handler */
1740	nfc_writel(host->nfc->hsmc_regs, IDR, flag);
1741	return -ETIMEDOUT;
1742}
1743
1744static int nfc_send_command(struct atmel_nand_host *host,
1745	unsigned int cmd, unsigned int addr, unsigned char cycle0)
1746{
1747	unsigned long timeout;
1748	u32 flag = NFC_SR_CMD_DONE;
1749	flag |= cmd & NFCADDR_CMD_DATAEN ? NFC_SR_XFR_DONE : 0;
1750
1751	dev_dbg(host->dev,
1752		"nfc_cmd: 0x%08x, addr1234: 0x%08x, cycle0: 0x%02x\n",
1753		cmd, addr, cycle0);
1754
1755	timeout = jiffies + msecs_to_jiffies(NFC_TIME_OUT_MS);
1756	while (nfc_readl(host->nfc->hsmc_regs, SR) & NFC_SR_BUSY) {
1757		if (time_after(jiffies, timeout)) {
1758			dev_err(host->dev,
1759				"Time out to wait for NFC ready!\n");
1760			return -ETIMEDOUT;
1761		}
1762	}
1763
1764	nfc_prepare_interrupt(host, flag);
1765	nfc_writel(host->nfc->hsmc_regs, CYCLE0, cycle0);
1766	nfc_cmd_addr1234_writel(cmd, addr, host->nfc->base_cmd_regs);
1767	return nfc_wait_interrupt(host, flag);
1768}
1769
1770static int nfc_device_ready(struct mtd_info *mtd)
1771{
1772	u32 status, mask;
1773	struct nand_chip *nand_chip = mtd->priv;
1774	struct atmel_nand_host *host = nand_chip->priv;
1775
1776	status = nfc_read_status(host);
1777	mask = nfc_readl(host->nfc->hsmc_regs, IMR);
1778
1779	/* The mask should be 0. If not we may lost interrupts */
1780	if (unlikely(mask & status))
1781		dev_err(host->dev, "Lost the interrupt flags: 0x%08x\n",
1782				mask & status);
1783
1784	return status & NFC_SR_RB_EDGE;
1785}
1786
1787static void nfc_select_chip(struct mtd_info *mtd, int chip)
1788{
1789	struct nand_chip *nand_chip = mtd->priv;
1790	struct atmel_nand_host *host = nand_chip->priv;
1791
1792	if (chip == -1)
1793		nfc_writel(host->nfc->hsmc_regs, CTRL, NFC_CTRL_DISABLE);
1794	else
1795		nfc_writel(host->nfc->hsmc_regs, CTRL, NFC_CTRL_ENABLE);
1796}
1797
1798static int nfc_make_addr(struct mtd_info *mtd, int command, int column,
1799		int page_addr, unsigned int *addr1234, unsigned int *cycle0)
1800{
1801	struct nand_chip *chip = mtd->priv;
1802
1803	int acycle = 0;
1804	unsigned char addr_bytes[8];
1805	int index = 0, bit_shift;
1806
1807	BUG_ON(addr1234 == NULL || cycle0 == NULL);
1808
1809	*cycle0 = 0;
1810	*addr1234 = 0;
1811
1812	if (column != -1) {
1813		if (chip->options & NAND_BUSWIDTH_16 &&
1814				!nand_opcode_8bits(command))
1815			column >>= 1;
1816		addr_bytes[acycle++] = column & 0xff;
1817		if (mtd->writesize > 512)
1818			addr_bytes[acycle++] = (column >> 8) & 0xff;
1819	}
1820
1821	if (page_addr != -1) {
1822		addr_bytes[acycle++] = page_addr & 0xff;
1823		addr_bytes[acycle++] = (page_addr >> 8) & 0xff;
1824		if (chip->chipsize > (128 << 20))
1825			addr_bytes[acycle++] = (page_addr >> 16) & 0xff;
1826	}
1827
1828	if (acycle > 4)
1829		*cycle0 = addr_bytes[index++];
1830
1831	for (bit_shift = 0; index < acycle; bit_shift += 8)
1832		*addr1234 += addr_bytes[index++] << bit_shift;
1833
1834	/* return acycle in cmd register */
1835	return acycle << NFCADDR_CMD_ACYCLE_BIT_POS;
1836}
1837
1838static void nfc_nand_command(struct mtd_info *mtd, unsigned int command,
1839				int column, int page_addr)
1840{
1841	struct nand_chip *chip = mtd->priv;
1842	struct atmel_nand_host *host = chip->priv;
1843	unsigned long timeout;
1844	unsigned int nfc_addr_cmd = 0;
1845
1846	unsigned int cmd1 = command << NFCADDR_CMD_CMD1_BIT_POS;
1847
1848	/* Set default settings: no cmd2, no addr cycle. read from nand */
1849	unsigned int cmd2 = 0;
1850	unsigned int vcmd2 = 0;
1851	int acycle = NFCADDR_CMD_ACYCLE_NONE;
1852	int csid = NFCADDR_CMD_CSID_3;
1853	int dataen = NFCADDR_CMD_DATADIS;
1854	int nfcwr = NFCADDR_CMD_NFCRD;
1855	unsigned int addr1234 = 0;
1856	unsigned int cycle0 = 0;
1857	bool do_addr = true;
1858	host->nfc->data_in_sram = NULL;
1859
1860	dev_dbg(host->dev, "%s: cmd = 0x%02x, col = 0x%08x, page = 0x%08x\n",
1861	     __func__, command, column, page_addr);
1862
1863	switch (command) {
1864	case NAND_CMD_RESET:
1865		nfc_addr_cmd = cmd1 | acycle | csid | dataen | nfcwr;
1866		nfc_send_command(host, nfc_addr_cmd, addr1234, cycle0);
1867		udelay(chip->chip_delay);
1868
1869		nfc_nand_command(mtd, NAND_CMD_STATUS, -1, -1);
1870		timeout = jiffies + msecs_to_jiffies(NFC_TIME_OUT_MS);
1871		while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) {
1872			if (time_after(jiffies, timeout)) {
1873				dev_err(host->dev,
1874					"Time out to wait status ready!\n");
1875				break;
1876			}
1877		}
1878		return;
1879	case NAND_CMD_STATUS:
1880		do_addr = false;
1881		break;
1882	case NAND_CMD_PARAM:
1883	case NAND_CMD_READID:
1884		do_addr = false;
1885		acycle = NFCADDR_CMD_ACYCLE_1;
1886		if (column != -1)
1887			addr1234 = column;
1888		break;
1889	case NAND_CMD_RNDOUT:
1890		cmd2 = NAND_CMD_RNDOUTSTART << NFCADDR_CMD_CMD2_BIT_POS;
1891		vcmd2 = NFCADDR_CMD_VCMD2;
1892		break;
1893	case NAND_CMD_READ0:
1894	case NAND_CMD_READOOB:
1895		if (command == NAND_CMD_READOOB) {
1896			column += mtd->writesize;
1897			command = NAND_CMD_READ0; /* only READ0 is valid */
1898			cmd1 = command << NFCADDR_CMD_CMD1_BIT_POS;
1899		}
1900		if (host->nfc->use_nfc_sram) {
1901			/* Enable Data transfer to sram */
1902			dataen = NFCADDR_CMD_DATAEN;
1903
1904			/* Need enable PMECC now, since NFC will transfer
1905			 * data in bus after sending nfc read command.
1906			 */
1907			if (chip->ecc.mode == NAND_ECC_HW && host->has_pmecc)
1908				pmecc_enable(host, NAND_ECC_READ);
1909		}
1910
1911		cmd2 = NAND_CMD_READSTART << NFCADDR_CMD_CMD2_BIT_POS;
1912		vcmd2 = NFCADDR_CMD_VCMD2;
1913		break;
1914	/* For prgramming command, the cmd need set to write enable */
1915	case NAND_CMD_PAGEPROG:
1916	case NAND_CMD_SEQIN:
1917	case NAND_CMD_RNDIN:
1918		nfcwr = NFCADDR_CMD_NFCWR;
1919		if (host->nfc->will_write_sram && command == NAND_CMD_SEQIN)
1920			dataen = NFCADDR_CMD_DATAEN;
1921		break;
1922	default:
1923		break;
1924	}
1925
1926	if (do_addr)
1927		acycle = nfc_make_addr(mtd, command, column, page_addr,
1928				&addr1234, &cycle0);
1929
1930	nfc_addr_cmd = cmd1 | cmd2 | vcmd2 | acycle | csid | dataen | nfcwr;
1931	nfc_send_command(host, nfc_addr_cmd, addr1234, cycle0);
1932
1933	/*
1934	 * Program and erase have their own busy handlers status, sequential
1935	 * in, and deplete1 need no delay.
1936	 */
1937	switch (command) {
1938	case NAND_CMD_CACHEDPROG:
1939	case NAND_CMD_PAGEPROG:
1940	case NAND_CMD_ERASE1:
1941	case NAND_CMD_ERASE2:
1942	case NAND_CMD_RNDIN:
1943	case NAND_CMD_STATUS:
1944	case NAND_CMD_RNDOUT:
1945	case NAND_CMD_SEQIN:
1946	case NAND_CMD_READID:
1947		return;
1948
1949	case NAND_CMD_READ0:
1950		if (dataen == NFCADDR_CMD_DATAEN) {
1951			host->nfc->data_in_sram = host->nfc->sram_bank0 +
1952				nfc_get_sram_off(host);
1953			return;
1954		}
1955		/* fall through */
1956	default:
1957		nfc_prepare_interrupt(host, NFC_SR_RB_EDGE);
1958		nfc_wait_interrupt(host, NFC_SR_RB_EDGE);
1959	}
1960}
1961
1962static int nfc_sram_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1963			uint32_t offset, int data_len, const uint8_t *buf,
1964			int oob_required, int page, int cached, int raw)
1965{
1966	int cfg, len;
1967	int status = 0;
1968	struct atmel_nand_host *host = chip->priv;
1969	void *sram = host->nfc->sram_bank0 + nfc_get_sram_off(host);
1970
1971	/* Subpage write is not supported */
1972	if (offset || (data_len < mtd->writesize))
1973		return -EINVAL;
1974
1975	len = mtd->writesize;
1976	/* Copy page data to sram that will write to nand via NFC */
1977	if (use_dma) {
1978		if (atmel_nand_dma_op(mtd, (void *)buf, len, 0) != 0)
1979			/* Fall back to use cpu copy */
1980			memcpy(sram, buf, len);
1981	} else {
1982		memcpy(sram, buf, len);
1983	}
1984
1985	cfg = nfc_readl(host->nfc->hsmc_regs, CFG);
1986	if (unlikely(raw) && oob_required) {
1987		memcpy(sram + len, chip->oob_poi, mtd->oobsize);
1988		len += mtd->oobsize;
1989		nfc_writel(host->nfc->hsmc_regs, CFG, cfg | NFC_CFG_WSPARE);
1990	} else {
1991		nfc_writel(host->nfc->hsmc_regs, CFG, cfg & ~NFC_CFG_WSPARE);
1992	}
1993
1994	if (chip->ecc.mode == NAND_ECC_HW && host->has_pmecc)
1995		/*
1996		 * When use NFC sram, need set up PMECC before send
1997		 * NAND_CMD_SEQIN command. Since when the nand command
1998		 * is sent, nfc will do transfer from sram and nand.
1999		 */
2000		pmecc_enable(host, NAND_ECC_WRITE);
2001
2002	host->nfc->will_write_sram = true;
2003	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
2004	host->nfc->will_write_sram = false;
2005
2006	if (likely(!raw))
2007		/* Need to write ecc into oob */
2008		status = chip->ecc.write_page(mtd, chip, buf, oob_required);
2009
2010	if (status < 0)
2011		return status;
2012
2013	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
2014	status = chip->waitfunc(mtd, chip);
2015
2016	if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2017		status = chip->errstat(mtd, chip, FL_WRITING, status, page);
2018
2019	if (status & NAND_STATUS_FAIL)
2020		return -EIO;
2021
2022	return 0;
2023}
2024
2025static int nfc_sram_init(struct mtd_info *mtd)
2026{
2027	struct nand_chip *chip = mtd->priv;
2028	struct atmel_nand_host *host = chip->priv;
2029	int res = 0;
2030
2031	/* Initialize the NFC CFG register */
2032	unsigned int cfg_nfc = 0;
2033
2034	/* set page size and oob layout */
2035	switch (mtd->writesize) {
2036	case 512:
2037		cfg_nfc = NFC_CFG_PAGESIZE_512;
2038		break;
2039	case 1024:
2040		cfg_nfc = NFC_CFG_PAGESIZE_1024;
2041		break;
2042	case 2048:
2043		cfg_nfc = NFC_CFG_PAGESIZE_2048;
2044		break;
2045	case 4096:
2046		cfg_nfc = NFC_CFG_PAGESIZE_4096;
2047		break;
2048	case 8192:
2049		cfg_nfc = NFC_CFG_PAGESIZE_8192;
2050		break;
2051	default:
2052		dev_err(host->dev, "Unsupported page size for NFC.\n");
2053		res = -ENXIO;
2054		return res;
2055	}
2056
2057	/* oob bytes size = (NFCSPARESIZE + 1) * 4
2058	 * Max support spare size is 512 bytes. */
2059	cfg_nfc |= (((mtd->oobsize / 4) - 1) << NFC_CFG_NFC_SPARESIZE_BIT_POS
2060		& NFC_CFG_NFC_SPARESIZE);
2061	/* default set a max timeout */
2062	cfg_nfc |= NFC_CFG_RSPARE |
2063			NFC_CFG_NFC_DTOCYC | NFC_CFG_NFC_DTOMUL;
2064
2065	nfc_writel(host->nfc->hsmc_regs, CFG, cfg_nfc);
2066
2067	host->nfc->will_write_sram = false;
2068	nfc_set_sram_bank(host, 0);
2069
2070	/* Use Write page with NFC SRAM only for PMECC or ECC NONE. */
2071	if (host->nfc->write_by_sram) {
2072		if ((chip->ecc.mode == NAND_ECC_HW && host->has_pmecc) ||
2073				chip->ecc.mode == NAND_ECC_NONE)
2074			chip->write_page = nfc_sram_write_page;
2075		else
2076			host->nfc->write_by_sram = false;
2077	}
2078
2079	dev_info(host->dev, "Using NFC Sram read %s\n",
2080			host->nfc->write_by_sram ? "and write" : "");
2081	return 0;
2082}
2083
2084static struct platform_driver atmel_nand_nfc_driver;
2085/*
2086 * Probe for the NAND device.
2087 */
2088static int atmel_nand_probe(struct platform_device *pdev)
2089{
2090	struct atmel_nand_host *host;
2091	struct mtd_info *mtd;
2092	struct nand_chip *nand_chip;
2093	struct resource *mem;
2094	struct mtd_part_parser_data ppdata = {};
2095	int res, irq;
2096
2097	/* Allocate memory for the device structure (and zero it) */
2098	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
2099	if (!host)
2100		return -ENOMEM;
2101
2102	res = platform_driver_register(&atmel_nand_nfc_driver);
2103	if (res)
2104		dev_err(&pdev->dev, "atmel_nand: can't register NFC driver\n");
2105
2106	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2107	host->io_base = devm_ioremap_resource(&pdev->dev, mem);
2108	if (IS_ERR(host->io_base)) {
2109		res = PTR_ERR(host->io_base);
2110		goto err_nand_ioremap;
2111	}
2112	host->io_phys = (dma_addr_t)mem->start;
2113
2114	mtd = &host->mtd;
2115	nand_chip = &host->nand_chip;
2116	host->dev = &pdev->dev;
2117	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
2118		/* Only when CONFIG_OF is enabled of_node can be parsed */
2119		res = atmel_of_init_port(host, pdev->dev.of_node);
2120		if (res)
2121			goto err_nand_ioremap;
2122	} else {
2123		memcpy(&host->board, dev_get_platdata(&pdev->dev),
2124		       sizeof(struct atmel_nand_data));
2125	}
2126
2127	nand_chip->priv = host;		/* link the private data structures */
2128	mtd->priv = nand_chip;
2129	mtd->owner = THIS_MODULE;
2130
2131	/* Set address of NAND IO lines */
2132	nand_chip->IO_ADDR_R = host->io_base;
2133	nand_chip->IO_ADDR_W = host->io_base;
2134
2135	if (nand_nfc.is_initialized) {
2136		/* NFC driver is probed and initialized */
2137		host->nfc = &nand_nfc;
2138
2139		nand_chip->select_chip = nfc_select_chip;
2140		nand_chip->dev_ready = nfc_device_ready;
2141		nand_chip->cmdfunc = nfc_nand_command;
2142
2143		/* Initialize the interrupt for NFC */
2144		irq = platform_get_irq(pdev, 0);
2145		if (irq < 0) {
2146			dev_err(host->dev, "Cannot get HSMC irq!\n");
2147			res = irq;
2148			goto err_nand_ioremap;
2149		}
2150
2151		res = devm_request_irq(&pdev->dev, irq, hsmc_interrupt,
2152				0, "hsmc", host);
2153		if (res) {
2154			dev_err(&pdev->dev, "Unable to request HSMC irq %d\n",
2155				irq);
2156			goto err_nand_ioremap;
2157		}
2158	} else {
2159		res = atmel_nand_set_enable_ready_pins(mtd);
2160		if (res)
2161			goto err_nand_ioremap;
2162
2163		nand_chip->cmd_ctrl = atmel_nand_cmd_ctrl;
2164	}
2165
2166	nand_chip->ecc.mode = host->board.ecc_mode;
2167	nand_chip->chip_delay = 40;		/* 40us command delay time */
2168
2169	if (host->board.bus_width_16)	/* 16-bit bus width */
2170		nand_chip->options |= NAND_BUSWIDTH_16;
2171
2172	nand_chip->read_buf = atmel_read_buf;
2173	nand_chip->write_buf = atmel_write_buf;
2174
2175	platform_set_drvdata(pdev, host);
2176	atmel_nand_enable(host);
2177
2178	if (gpio_is_valid(host->board.det_pin)) {
2179		res = devm_gpio_request(&pdev->dev,
2180				host->board.det_pin, "nand_det");
2181		if (res < 0) {
2182			dev_err(&pdev->dev,
2183				"can't request det gpio %d\n",
2184				host->board.det_pin);
2185			goto err_no_card;
2186		}
2187
2188		res = gpio_direction_input(host->board.det_pin);
2189		if (res < 0) {
2190			dev_err(&pdev->dev,
2191				"can't request input direction det gpio %d\n",
2192				host->board.det_pin);
2193			goto err_no_card;
2194		}
2195
2196		if (gpio_get_value(host->board.det_pin)) {
2197			dev_info(&pdev->dev, "No SmartMedia card inserted.\n");
2198			res = -ENXIO;
2199			goto err_no_card;
2200		}
2201	}
2202
2203	if (host->board.on_flash_bbt || on_flash_bbt) {
2204		dev_info(&pdev->dev, "Use On Flash BBT\n");
2205		nand_chip->bbt_options |= NAND_BBT_USE_FLASH;
2206	}
2207
2208	if (!host->board.has_dma)
2209		use_dma = 0;
2210
2211	if (use_dma) {
2212		dma_cap_mask_t mask;
2213
2214		dma_cap_zero(mask);
2215		dma_cap_set(DMA_MEMCPY, mask);
2216		host->dma_chan = dma_request_channel(mask, NULL, NULL);
2217		if (!host->dma_chan) {
2218			dev_err(host->dev, "Failed to request DMA channel\n");
2219			use_dma = 0;
2220		}
2221	}
2222	if (use_dma)
2223		dev_info(host->dev, "Using %s for DMA transfers.\n",
2224					dma_chan_name(host->dma_chan));
2225	else
2226		dev_info(host->dev, "No DMA support for NAND access.\n");
2227
2228	/* first scan to find the device and get the page size */
2229	if (nand_scan_ident(mtd, 1, NULL)) {
2230		res = -ENXIO;
2231		goto err_scan_ident;
2232	}
2233
2234	if (nand_chip->ecc.mode == NAND_ECC_HW) {
2235		if (host->has_pmecc)
2236			res = atmel_pmecc_nand_init_params(pdev, host);
2237		else
2238			res = atmel_hw_nand_init_params(pdev, host);
2239
2240		if (res != 0)
2241			goto err_hw_ecc;
2242	}
2243
2244	/* initialize the nfc configuration register */
2245	if (host->nfc && host->nfc->use_nfc_sram) {
2246		res = nfc_sram_init(mtd);
2247		if (res) {
2248			host->nfc->use_nfc_sram = false;
2249			dev_err(host->dev, "Disable use nfc sram for data transfer.\n");
2250		}
2251	}
2252
2253	/* second phase scan */
2254	if (nand_scan_tail(mtd)) {
2255		res = -ENXIO;
2256		goto err_scan_tail;
2257	}
2258
2259	mtd->name = "atmel_nand";
2260	ppdata.of_node = pdev->dev.of_node;
2261	res = mtd_device_parse_register(mtd, NULL, &ppdata,
2262			host->board.parts, host->board.num_parts);
2263	if (!res)
2264		return res;
2265
2266err_scan_tail:
2267	if (host->has_pmecc && host->nand_chip.ecc.mode == NAND_ECC_HW)
2268		pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
2269err_hw_ecc:
2270err_scan_ident:
2271err_no_card:
2272	atmel_nand_disable(host);
2273	if (host->dma_chan)
2274		dma_release_channel(host->dma_chan);
2275err_nand_ioremap:
2276	return res;
2277}
2278
2279/*
2280 * Remove a NAND device.
2281 */
2282static int atmel_nand_remove(struct platform_device *pdev)
2283{
2284	struct atmel_nand_host *host = platform_get_drvdata(pdev);
2285	struct mtd_info *mtd = &host->mtd;
2286
2287	nand_release(mtd);
2288
2289	atmel_nand_disable(host);
2290
2291	if (host->has_pmecc && host->nand_chip.ecc.mode == NAND_ECC_HW) {
2292		pmecc_writel(host->ecc, CTRL, PMECC_CTRL_DISABLE);
2293		pmerrloc_writel(host->pmerrloc_base, ELDIS,
2294				PMERRLOC_DISABLE);
2295	}
2296
2297	if (host->dma_chan)
2298		dma_release_channel(host->dma_chan);
2299
2300	platform_driver_unregister(&atmel_nand_nfc_driver);
2301
2302	return 0;
2303}
2304
2305static struct atmel_nand_caps at91rm9200_caps = {
2306	.pmecc_correct_erase_page = false,
2307};
2308
2309static struct atmel_nand_caps sama5d4_caps = {
2310	.pmecc_correct_erase_page = true,
2311};
2312
2313static const struct of_device_id atmel_nand_dt_ids[] = {
2314	{ .compatible = "atmel,at91rm9200-nand", .data = &at91rm9200_caps },
2315	{ .compatible = "atmel,sama5d4-nand", .data = &sama5d4_caps },
2316	{ /* sentinel */ }
2317};
2318
2319MODULE_DEVICE_TABLE(of, atmel_nand_dt_ids);
2320
2321static int atmel_nand_nfc_probe(struct platform_device *pdev)
2322{
2323	struct atmel_nfc *nfc = &nand_nfc;
2324	struct resource *nfc_cmd_regs, *nfc_hsmc_regs, *nfc_sram;
2325	int ret;
2326
2327	nfc_cmd_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2328	nfc->base_cmd_regs = devm_ioremap_resource(&pdev->dev, nfc_cmd_regs);
2329	if (IS_ERR(nfc->base_cmd_regs))
2330		return PTR_ERR(nfc->base_cmd_regs);
2331
2332	nfc_hsmc_regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
2333	nfc->hsmc_regs = devm_ioremap_resource(&pdev->dev, nfc_hsmc_regs);
2334	if (IS_ERR(nfc->hsmc_regs))
2335		return PTR_ERR(nfc->hsmc_regs);
2336
2337	nfc_sram = platform_get_resource(pdev, IORESOURCE_MEM, 2);
2338	if (nfc_sram) {
2339		nfc->sram_bank0 = (void * __force)
2340				devm_ioremap_resource(&pdev->dev, nfc_sram);
2341		if (IS_ERR(nfc->sram_bank0)) {
2342			dev_warn(&pdev->dev, "Fail to ioremap the NFC sram with error: %ld. So disable NFC sram.\n",
2343					PTR_ERR(nfc->sram_bank0));
2344		} else {
2345			nfc->use_nfc_sram = true;
2346			nfc->sram_bank0_phys = (dma_addr_t)nfc_sram->start;
2347
2348			if (pdev->dev.of_node)
2349				nfc->write_by_sram = of_property_read_bool(
2350						pdev->dev.of_node,
2351						"atmel,write-by-sram");
2352		}
2353	}
2354
2355	nfc_writel(nfc->hsmc_regs, IDR, 0xffffffff);
2356	nfc_readl(nfc->hsmc_regs, SR);	/* clear the NFC_SR */
2357
2358	nfc->clk = devm_clk_get(&pdev->dev, NULL);
2359	if (!IS_ERR(nfc->clk)) {
2360		ret = clk_prepare_enable(nfc->clk);
2361		if (ret)
2362			return ret;
2363	} else {
2364		dev_warn(&pdev->dev, "NFC clock missing, update your Device Tree");
2365	}
2366
2367	nfc->is_initialized = true;
2368	dev_info(&pdev->dev, "NFC is probed.\n");
2369
2370	return 0;
2371}
2372
2373static int atmel_nand_nfc_remove(struct platform_device *pdev)
2374{
2375	struct atmel_nfc *nfc = &nand_nfc;
2376
2377	if (!IS_ERR(nfc->clk))
2378		clk_disable_unprepare(nfc->clk);
2379
2380	return 0;
2381}
2382
2383static const struct of_device_id atmel_nand_nfc_match[] = {
2384	{ .compatible = "atmel,sama5d3-nfc" },
2385	{ /* sentinel */ }
2386};
2387MODULE_DEVICE_TABLE(of, atmel_nand_nfc_match);
2388
2389static struct platform_driver atmel_nand_nfc_driver = {
2390	.driver = {
2391		.name = "atmel_nand_nfc",
2392		.of_match_table = of_match_ptr(atmel_nand_nfc_match),
2393	},
2394	.probe = atmel_nand_nfc_probe,
2395	.remove = atmel_nand_nfc_remove,
2396};
2397
2398static struct platform_driver atmel_nand_driver = {
2399	.probe		= atmel_nand_probe,
2400	.remove		= atmel_nand_remove,
2401	.driver		= {
2402		.name	= "atmel_nand",
2403		.of_match_table	= of_match_ptr(atmel_nand_dt_ids),
2404	},
2405};
2406
2407module_platform_driver(atmel_nand_driver);
2408
2409MODULE_LICENSE("GPL");
2410MODULE_AUTHOR("Rick Bronson");
2411MODULE_DESCRIPTION("NAND/SmartMedia driver for AT91 / AVR32");
2412MODULE_ALIAS("platform:atmel_nand");
2413