1// SPDX-License-Identifier: GPL-2.0
2/*
3 * ST Microelectronics
4 * Flexible Static Memory Controller (FSMC)
5 * Driver for NAND portions
6 *
7 * Copyright © 2010 ST Microelectronics
8 * Vipin Kumar <vipin.kumar@st.com>
9 * Ashish Priyadarshi
10 *
11 * Based on drivers/mtd/nand/nomadik_nand.c (removed in v3.8)
12 *  Copyright © 2007 STMicroelectronics Pvt. Ltd.
13 *  Copyright © 2009 Alessandro Rubini
14 */
15
16#include <linux/clk.h>
17#include <linux/completion.h>
18#include <linux/delay.h>
19#include <linux/dmaengine.h>
20#include <linux/dma-direction.h>
21#include <linux/dma-mapping.h>
22#include <linux/err.h>
23#include <linux/init.h>
24#include <linux/module.h>
25#include <linux/resource.h>
26#include <linux/sched.h>
27#include <linux/types.h>
28#include <linux/mtd/mtd.h>
29#include <linux/mtd/rawnand.h>
30#include <linux/mtd/nand_ecc.h>
31#include <linux/platform_device.h>
32#include <linux/of.h>
33#include <linux/mtd/partitions.h>
34#include <linux/io.h>
35#include <linux/slab.h>
36#include <linux/amba/bus.h>
37#include <mtd/mtd-abi.h>
38
39/* fsmc controller registers for NOR flash */
40#define CTRL			0x0
41	/* ctrl register definitions */
42	#define BANK_ENABLE		BIT(0)
43	#define MUXED			BIT(1)
44	#define NOR_DEV			(2 << 2)
45	#define WIDTH_16		BIT(4)
46	#define RSTPWRDWN		BIT(6)
47	#define WPROT			BIT(7)
48	#define WRT_ENABLE		BIT(12)
49	#define WAIT_ENB		BIT(13)
50
51#define CTRL_TIM		0x4
52	/* ctrl_tim register definitions */
53
54#define FSMC_NOR_BANK_SZ	0x8
55#define FSMC_NOR_REG_SIZE	0x40
56
57#define FSMC_NOR_REG(base, bank, reg)	((base) +			\
58					 (FSMC_NOR_BANK_SZ * (bank)) +	\
59					 (reg))
60
61/* fsmc controller registers for NAND flash */
62#define FSMC_PC			0x00
63	/* pc register definitions */
64	#define FSMC_RESET		BIT(0)
65	#define FSMC_WAITON		BIT(1)
66	#define FSMC_ENABLE		BIT(2)
67	#define FSMC_DEVTYPE_NAND	BIT(3)
68	#define FSMC_DEVWID_16		BIT(4)
69	#define FSMC_ECCEN		BIT(6)
70	#define FSMC_ECCPLEN_256	BIT(7)
71	#define FSMC_TCLR_SHIFT		(9)
72	#define FSMC_TCLR_MASK		(0xF)
73	#define FSMC_TAR_SHIFT		(13)
74	#define FSMC_TAR_MASK		(0xF)
75#define STS			0x04
76	/* sts register definitions */
77	#define FSMC_CODE_RDY		BIT(15)
78#define COMM			0x08
79	/* comm register definitions */
80	#define FSMC_TSET_SHIFT		0
81	#define FSMC_TSET_MASK		0xFF
82	#define FSMC_TWAIT_SHIFT	8
83	#define FSMC_TWAIT_MASK		0xFF
84	#define FSMC_THOLD_SHIFT	16
85	#define FSMC_THOLD_MASK		0xFF
86	#define FSMC_THIZ_SHIFT		24
87	#define FSMC_THIZ_MASK		0xFF
88#define ATTRIB			0x0C
89#define IOATA			0x10
90#define ECC1			0x14
91#define ECC2			0x18
92#define ECC3			0x1C
93#define FSMC_NAND_BANK_SZ	0x20
94
95#define FSMC_BUSY_WAIT_TIMEOUT	(1 * HZ)
96
97/*
98 * According to SPEAr300 Reference Manual (RM0082)
99 *  TOUDEL = 7ns (Output delay from the flip-flops to the board)
100 *  TINDEL = 5ns (Input delay from the board to the flipflop)
101 */
102#define TOUTDEL	7000
103#define TINDEL	5000
104
105struct fsmc_nand_timings {
106	u8 tclr;
107	u8 tar;
108	u8 thiz;
109	u8 thold;
110	u8 twait;
111	u8 tset;
112};
113
114enum access_mode {
115	USE_DMA_ACCESS = 1,
116	USE_WORD_ACCESS,
117};
118
119/**
120 * struct fsmc_nand_data - structure for FSMC NAND device state
121 *
122 * @base:		Inherit from the nand_controller struct
123 * @pid:		Part ID on the AMBA PrimeCell format
124 * @nand:		Chip related info for a NAND flash.
125 *
126 * @bank:		Bank number for probed device.
127 * @dev:		Parent device
128 * @mode:		Access mode
129 * @clk:		Clock structure for FSMC.
130 *
131 * @read_dma_chan:	DMA channel for read access
132 * @write_dma_chan:	DMA channel for write access to NAND
133 * @dma_access_complete: Completion structure
134 *
135 * @dev_timings:	NAND timings
136 *
137 * @data_pa:		NAND Physical port for Data.
138 * @data_va:		NAND port for Data.
139 * @cmd_va:		NAND port for Command.
140 * @addr_va:		NAND port for Address.
141 * @regs_va:		Registers base address for a given bank.
142 */
143struct fsmc_nand_data {
144	struct nand_controller	base;
145	u32			pid;
146	struct nand_chip	nand;
147
148	unsigned int		bank;
149	struct device		*dev;
150	enum access_mode	mode;
151	struct clk		*clk;
152
153	/* DMA related objects */
154	struct dma_chan		*read_dma_chan;
155	struct dma_chan		*write_dma_chan;
156	struct completion	dma_access_complete;
157
158	struct fsmc_nand_timings *dev_timings;
159
160	dma_addr_t		data_pa;
161	void __iomem		*data_va;
162	void __iomem		*cmd_va;
163	void __iomem		*addr_va;
164	void __iomem		*regs_va;
165};
166
167static int fsmc_ecc1_ooblayout_ecc(struct mtd_info *mtd, int section,
168				   struct mtd_oob_region *oobregion)
169{
170	struct nand_chip *chip = mtd_to_nand(mtd);
171
172	if (section >= chip->ecc.steps)
173		return -ERANGE;
174
175	oobregion->offset = (section * 16) + 2;
176	oobregion->length = 3;
177
178	return 0;
179}
180
181static int fsmc_ecc1_ooblayout_free(struct mtd_info *mtd, int section,
182				    struct mtd_oob_region *oobregion)
183{
184	struct nand_chip *chip = mtd_to_nand(mtd);
185
186	if (section >= chip->ecc.steps)
187		return -ERANGE;
188
189	oobregion->offset = (section * 16) + 8;
190
191	if (section < chip->ecc.steps - 1)
192		oobregion->length = 8;
193	else
194		oobregion->length = mtd->oobsize - oobregion->offset;
195
196	return 0;
197}
198
199static const struct mtd_ooblayout_ops fsmc_ecc1_ooblayout_ops = {
200	.ecc = fsmc_ecc1_ooblayout_ecc,
201	.free = fsmc_ecc1_ooblayout_free,
202};
203
204/*
205 * ECC placement definitions in oobfree type format.
206 * There are 13 bytes of ecc for every 512 byte block and it has to be read
207 * consecutively and immediately after the 512 byte data block for hardware to
208 * generate the error bit offsets in 512 byte data.
209 */
210static int fsmc_ecc4_ooblayout_ecc(struct mtd_info *mtd, int section,
211				   struct mtd_oob_region *oobregion)
212{
213	struct nand_chip *chip = mtd_to_nand(mtd);
214
215	if (section >= chip->ecc.steps)
216		return -ERANGE;
217
218	oobregion->length = chip->ecc.bytes;
219
220	if (!section && mtd->writesize <= 512)
221		oobregion->offset = 0;
222	else
223		oobregion->offset = (section * 16) + 2;
224
225	return 0;
226}
227
228static int fsmc_ecc4_ooblayout_free(struct mtd_info *mtd, int section,
229				    struct mtd_oob_region *oobregion)
230{
231	struct nand_chip *chip = mtd_to_nand(mtd);
232
233	if (section >= chip->ecc.steps)
234		return -ERANGE;
235
236	oobregion->offset = (section * 16) + 15;
237
238	if (section < chip->ecc.steps - 1)
239		oobregion->length = 3;
240	else
241		oobregion->length = mtd->oobsize - oobregion->offset;
242
243	return 0;
244}
245
246static const struct mtd_ooblayout_ops fsmc_ecc4_ooblayout_ops = {
247	.ecc = fsmc_ecc4_ooblayout_ecc,
248	.free = fsmc_ecc4_ooblayout_free,
249};
250
251static inline struct fsmc_nand_data *nand_to_fsmc(struct nand_chip *chip)
252{
253	return container_of(chip, struct fsmc_nand_data, nand);
254}
255
256/*
257 * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
258 *
259 * This routine initializes timing parameters related to NAND memory access in
260 * FSMC registers
261 */
262static void fsmc_nand_setup(struct fsmc_nand_data *host,
263			    struct fsmc_nand_timings *tims)
264{
265	u32 value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
266	u32 tclr, tar, thiz, thold, twait, tset;
267
268	tclr = (tims->tclr & FSMC_TCLR_MASK) << FSMC_TCLR_SHIFT;
269	tar = (tims->tar & FSMC_TAR_MASK) << FSMC_TAR_SHIFT;
270	thiz = (tims->thiz & FSMC_THIZ_MASK) << FSMC_THIZ_SHIFT;
271	thold = (tims->thold & FSMC_THOLD_MASK) << FSMC_THOLD_SHIFT;
272	twait = (tims->twait & FSMC_TWAIT_MASK) << FSMC_TWAIT_SHIFT;
273	tset = (tims->tset & FSMC_TSET_MASK) << FSMC_TSET_SHIFT;
274
275	if (host->nand.options & NAND_BUSWIDTH_16)
276		value |= FSMC_DEVWID_16;
277
278	writel_relaxed(value | tclr | tar, host->regs_va + FSMC_PC);
279	writel_relaxed(thiz | thold | twait | tset, host->regs_va + COMM);
280	writel_relaxed(thiz | thold | twait | tset, host->regs_va + ATTRIB);
281}
282
283static int fsmc_calc_timings(struct fsmc_nand_data *host,
284			     const struct nand_sdr_timings *sdrt,
285			     struct fsmc_nand_timings *tims)
286{
287	unsigned long hclk = clk_get_rate(host->clk);
288	unsigned long hclkn = NSEC_PER_SEC / hclk;
289	u32 thiz, thold, twait, tset, twait_min;
290
291	if (sdrt->tRC_min < 30000)
292		return -EOPNOTSUPP;
293
294	tims->tar = DIV_ROUND_UP(sdrt->tAR_min / 1000, hclkn) - 1;
295	if (tims->tar > FSMC_TAR_MASK)
296		tims->tar = FSMC_TAR_MASK;
297	tims->tclr = DIV_ROUND_UP(sdrt->tCLR_min / 1000, hclkn) - 1;
298	if (tims->tclr > FSMC_TCLR_MASK)
299		tims->tclr = FSMC_TCLR_MASK;
300
301	thiz = sdrt->tCS_min - sdrt->tWP_min;
302	tims->thiz = DIV_ROUND_UP(thiz / 1000, hclkn);
303
304	thold = sdrt->tDH_min;
305	if (thold < sdrt->tCH_min)
306		thold = sdrt->tCH_min;
307	if (thold < sdrt->tCLH_min)
308		thold = sdrt->tCLH_min;
309	if (thold < sdrt->tWH_min)
310		thold = sdrt->tWH_min;
311	if (thold < sdrt->tALH_min)
312		thold = sdrt->tALH_min;
313	if (thold < sdrt->tREH_min)
314		thold = sdrt->tREH_min;
315	tims->thold = DIV_ROUND_UP(thold / 1000, hclkn);
316	if (tims->thold == 0)
317		tims->thold = 1;
318	else if (tims->thold > FSMC_THOLD_MASK)
319		tims->thold = FSMC_THOLD_MASK;
320
321	tset = max(sdrt->tCS_min - sdrt->tWP_min,
322		   sdrt->tCEA_max - sdrt->tREA_max);
323	tims->tset = DIV_ROUND_UP(tset / 1000, hclkn) - 1;
324	if (tims->tset == 0)
325		tims->tset = 1;
326	else if (tims->tset > FSMC_TSET_MASK)
327		tims->tset = FSMC_TSET_MASK;
328
329	/*
330	 * According to SPEAr300 Reference Manual (RM0082) which gives more
331	 * information related to FSMSC timings than the SPEAr600 one (RM0305),
332	 *   twait >= tCEA - (tset * TCLK) + TOUTDEL + TINDEL
333	 */
334	twait_min = sdrt->tCEA_max - ((tims->tset + 1) * hclkn * 1000)
335		    + TOUTDEL + TINDEL;
336	twait = max3(sdrt->tRP_min, sdrt->tWP_min, twait_min);
337
338	tims->twait = DIV_ROUND_UP(twait / 1000, hclkn) - 1;
339	if (tims->twait == 0)
340		tims->twait = 1;
341	else if (tims->twait > FSMC_TWAIT_MASK)
342		tims->twait = FSMC_TWAIT_MASK;
343
344	return 0;
345}
346
347static int fsmc_setup_interface(struct nand_chip *nand, int csline,
348				const struct nand_interface_config *conf)
349{
350	struct fsmc_nand_data *host = nand_to_fsmc(nand);
351	struct fsmc_nand_timings tims;
352	const struct nand_sdr_timings *sdrt;
353	int ret;
354
355	sdrt = nand_get_sdr_timings(conf);
356	if (IS_ERR(sdrt))
357		return PTR_ERR(sdrt);
358
359	ret = fsmc_calc_timings(host, sdrt, &tims);
360	if (ret)
361		return ret;
362
363	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
364		return 0;
365
366	fsmc_nand_setup(host, &tims);
367
368	return 0;
369}
370
371/*
372 * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
373 */
374static void fsmc_enable_hwecc(struct nand_chip *chip, int mode)
375{
376	struct fsmc_nand_data *host = nand_to_fsmc(chip);
377
378	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCPLEN_256,
379		       host->regs_va + FSMC_PC);
380	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCEN,
381		       host->regs_va + FSMC_PC);
382	writel_relaxed(readl(host->regs_va + FSMC_PC) | FSMC_ECCEN,
383		       host->regs_va + FSMC_PC);
384}
385
386/*
387 * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
388 * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
389 * max of 8-bits)
390 */
391static int fsmc_read_hwecc_ecc4(struct nand_chip *chip, const u8 *data,
392				u8 *ecc)
393{
394	struct fsmc_nand_data *host = nand_to_fsmc(chip);
395	u32 ecc_tmp;
396	unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;
397
398	do {
399		if (readl_relaxed(host->regs_va + STS) & FSMC_CODE_RDY)
400			break;
401
402		cond_resched();
403	} while (!time_after_eq(jiffies, deadline));
404
405	if (time_after_eq(jiffies, deadline)) {
406		dev_err(host->dev, "calculate ecc timed out\n");
407		return -ETIMEDOUT;
408	}
409
410	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
411	ecc[0] = ecc_tmp;
412	ecc[1] = ecc_tmp >> 8;
413	ecc[2] = ecc_tmp >> 16;
414	ecc[3] = ecc_tmp >> 24;
415
416	ecc_tmp = readl_relaxed(host->regs_va + ECC2);
417	ecc[4] = ecc_tmp;
418	ecc[5] = ecc_tmp >> 8;
419	ecc[6] = ecc_tmp >> 16;
420	ecc[7] = ecc_tmp >> 24;
421
422	ecc_tmp = readl_relaxed(host->regs_va + ECC3);
423	ecc[8] = ecc_tmp;
424	ecc[9] = ecc_tmp >> 8;
425	ecc[10] = ecc_tmp >> 16;
426	ecc[11] = ecc_tmp >> 24;
427
428	ecc_tmp = readl_relaxed(host->regs_va + STS);
429	ecc[12] = ecc_tmp >> 16;
430
431	return 0;
432}
433
434/*
435 * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
436 * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
437 * max of 1-bit)
438 */
439static int fsmc_read_hwecc_ecc1(struct nand_chip *chip, const u8 *data,
440				u8 *ecc)
441{
442	struct fsmc_nand_data *host = nand_to_fsmc(chip);
443	u32 ecc_tmp;
444
445	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
446	ecc[0] = ecc_tmp;
447	ecc[1] = ecc_tmp >> 8;
448	ecc[2] = ecc_tmp >> 16;
449
450	return 0;
451}
452
453/* Count the number of 0's in buff upto a max of max_bits */
454static int count_written_bits(u8 *buff, int size, int max_bits)
455{
456	int k, written_bits = 0;
457
458	for (k = 0; k < size; k++) {
459		written_bits += hweight8(~buff[k]);
460		if (written_bits > max_bits)
461			break;
462	}
463
464	return written_bits;
465}
466
467static void dma_complete(void *param)
468{
469	struct fsmc_nand_data *host = param;
470
471	complete(&host->dma_access_complete);
472}
473
474static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
475		    enum dma_data_direction direction)
476{
477	struct dma_chan *chan;
478	struct dma_device *dma_dev;
479	struct dma_async_tx_descriptor *tx;
480	dma_addr_t dma_dst, dma_src, dma_addr;
481	dma_cookie_t cookie;
482	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
483	int ret;
484	unsigned long time_left;
485
486	if (direction == DMA_TO_DEVICE)
487		chan = host->write_dma_chan;
488	else if (direction == DMA_FROM_DEVICE)
489		chan = host->read_dma_chan;
490	else
491		return -EINVAL;
492
493	dma_dev = chan->device;
494	dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
495
496	if (direction == DMA_TO_DEVICE) {
497		dma_src = dma_addr;
498		dma_dst = host->data_pa;
499	} else {
500		dma_src = host->data_pa;
501		dma_dst = dma_addr;
502	}
503
504	tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
505			len, flags);
506	if (!tx) {
507		dev_err(host->dev, "device_prep_dma_memcpy error\n");
508		ret = -EIO;
509		goto unmap_dma;
510	}
511
512	tx->callback = dma_complete;
513	tx->callback_param = host;
514	cookie = tx->tx_submit(tx);
515
516	ret = dma_submit_error(cookie);
517	if (ret) {
518		dev_err(host->dev, "dma_submit_error %d\n", cookie);
519		goto unmap_dma;
520	}
521
522	dma_async_issue_pending(chan);
523
524	time_left =
525	wait_for_completion_timeout(&host->dma_access_complete,
526				    msecs_to_jiffies(3000));
527	if (time_left == 0) {
528		dmaengine_terminate_all(chan);
529		dev_err(host->dev, "wait_for_completion_timeout\n");
530		ret = -ETIMEDOUT;
531		goto unmap_dma;
532	}
533
534	ret = 0;
535
536unmap_dma:
537	dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
538
539	return ret;
540}
541
542/*
543 * fsmc_write_buf - write buffer to chip
544 * @host:	FSMC NAND controller
545 * @buf:	data buffer
546 * @len:	number of bytes to write
547 */
548static void fsmc_write_buf(struct fsmc_nand_data *host, const u8 *buf,
549			   int len)
550{
551	int i;
552
553	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
554	    IS_ALIGNED(len, sizeof(u32))) {
555		u32 *p = (u32 *)buf;
556
557		len = len >> 2;
558		for (i = 0; i < len; i++)
559			writel_relaxed(p[i], host->data_va);
560	} else {
561		for (i = 0; i < len; i++)
562			writeb_relaxed(buf[i], host->data_va);
563	}
564}
565
566/*
567 * fsmc_read_buf - read chip data into buffer
568 * @host:	FSMC NAND controller
569 * @buf:	buffer to store date
570 * @len:	number of bytes to read
571 */
572static void fsmc_read_buf(struct fsmc_nand_data *host, u8 *buf, int len)
573{
574	int i;
575
576	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
577	    IS_ALIGNED(len, sizeof(u32))) {
578		u32 *p = (u32 *)buf;
579
580		len = len >> 2;
581		for (i = 0; i < len; i++)
582			p[i] = readl_relaxed(host->data_va);
583	} else {
584		for (i = 0; i < len; i++)
585			buf[i] = readb_relaxed(host->data_va);
586	}
587}
588
589/*
590 * fsmc_read_buf_dma - read chip data into buffer
591 * @host:	FSMC NAND controller
592 * @buf:	buffer to store date
593 * @len:	number of bytes to read
594 */
595static void fsmc_read_buf_dma(struct fsmc_nand_data *host, u8 *buf,
596			      int len)
597{
598	dma_xfer(host, buf, len, DMA_FROM_DEVICE);
599}
600
601/*
602 * fsmc_write_buf_dma - write buffer to chip
603 * @host:	FSMC NAND controller
604 * @buf:	data buffer
605 * @len:	number of bytes to write
606 */
607static void fsmc_write_buf_dma(struct fsmc_nand_data *host, const u8 *buf,
608			       int len)
609{
610	dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
611}
612
613/*
614 * fsmc_exec_op - hook called by the core to execute NAND operations
615 *
616 * This controller is simple enough and thus does not need to use the parser
617 * provided by the core, instead, handle every situation here.
618 */
619static int fsmc_exec_op(struct nand_chip *chip, const struct nand_operation *op,
620			bool check_only)
621{
622	struct fsmc_nand_data *host = nand_to_fsmc(chip);
623	const struct nand_op_instr *instr = NULL;
624	int ret = 0;
625	unsigned int op_id;
626	int i;
627
628	if (check_only)
629		return 0;
630
631	pr_debug("Executing operation [%d instructions]:\n", op->ninstrs);
632
633	for (op_id = 0; op_id < op->ninstrs; op_id++) {
634		instr = &op->instrs[op_id];
635
636		nand_op_trace("  ", instr);
637
638		switch (instr->type) {
639		case NAND_OP_CMD_INSTR:
640			writeb_relaxed(instr->ctx.cmd.opcode, host->cmd_va);
641			break;
642
643		case NAND_OP_ADDR_INSTR:
644			for (i = 0; i < instr->ctx.addr.naddrs; i++)
645				writeb_relaxed(instr->ctx.addr.addrs[i],
646					       host->addr_va);
647			break;
648
649		case NAND_OP_DATA_IN_INSTR:
650			if (host->mode == USE_DMA_ACCESS)
651				fsmc_read_buf_dma(host, instr->ctx.data.buf.in,
652						  instr->ctx.data.len);
653			else
654				fsmc_read_buf(host, instr->ctx.data.buf.in,
655					      instr->ctx.data.len);
656			break;
657
658		case NAND_OP_DATA_OUT_INSTR:
659			if (host->mode == USE_DMA_ACCESS)
660				fsmc_write_buf_dma(host,
661						   instr->ctx.data.buf.out,
662						   instr->ctx.data.len);
663			else
664				fsmc_write_buf(host, instr->ctx.data.buf.out,
665					       instr->ctx.data.len);
666			break;
667
668		case NAND_OP_WAITRDY_INSTR:
669			ret = nand_soft_waitrdy(chip,
670						instr->ctx.waitrdy.timeout_ms);
671			break;
672		}
673
674		if (instr->delay_ns)
675			ndelay(instr->delay_ns);
676	}
677
678	return ret;
679}
680
681/*
682 * fsmc_read_page_hwecc
683 * @chip:	nand chip info structure
684 * @buf:	buffer to store read data
685 * @oob_required:	caller expects OOB data read to chip->oob_poi
686 * @page:	page number to read
687 *
688 * This routine is needed for fsmc version 8 as reading from NAND chip has to be
689 * performed in a strict sequence as follows:
690 * data(512 byte) -> ecc(13 byte)
691 * After this read, fsmc hardware generates and reports error data bits(up to a
692 * max of 8 bits)
693 */
694static int fsmc_read_page_hwecc(struct nand_chip *chip, u8 *buf,
695				int oob_required, int page)
696{
697	struct mtd_info *mtd = nand_to_mtd(chip);
698	int i, j, s, stat, eccsize = chip->ecc.size;
699	int eccbytes = chip->ecc.bytes;
700	int eccsteps = chip->ecc.steps;
701	u8 *p = buf;
702	u8 *ecc_calc = chip->ecc.calc_buf;
703	u8 *ecc_code = chip->ecc.code_buf;
704	int off, len, ret, group = 0;
705	/*
706	 * ecc_oob is intentionally taken as u16. In 16bit devices, we
707	 * end up reading 14 bytes (7 words) from oob. The local array is
708	 * to maintain word alignment
709	 */
710	u16 ecc_oob[7];
711	u8 *oob = (u8 *)&ecc_oob[0];
712	unsigned int max_bitflips = 0;
713
714	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
715		nand_read_page_op(chip, page, s * eccsize, NULL, 0);
716		chip->ecc.hwctl(chip, NAND_ECC_READ);
717		ret = nand_read_data_op(chip, p, eccsize, false, false);
718		if (ret)
719			return ret;
720
721		for (j = 0; j < eccbytes;) {
722			struct mtd_oob_region oobregion;
723
724			ret = mtd_ooblayout_ecc(mtd, group++, &oobregion);
725			if (ret)
726				return ret;
727
728			off = oobregion.offset;
729			len = oobregion.length;
730
731			/*
732			 * length is intentionally kept a higher multiple of 2
733			 * to read at least 13 bytes even in case of 16 bit NAND
734			 * devices
735			 */
736			if (chip->options & NAND_BUSWIDTH_16)
737				len = roundup(len, 2);
738
739			nand_read_oob_op(chip, page, off, oob + j, len);
740			j += len;
741		}
742
743		memcpy(&ecc_code[i], oob, chip->ecc.bytes);
744		chip->ecc.calculate(chip, p, &ecc_calc[i]);
745
746		stat = chip->ecc.correct(chip, p, &ecc_code[i], &ecc_calc[i]);
747		if (stat < 0) {
748			mtd->ecc_stats.failed++;
749		} else {
750			mtd->ecc_stats.corrected += stat;
751			max_bitflips = max_t(unsigned int, max_bitflips, stat);
752		}
753	}
754
755	return max_bitflips;
756}
757
758/*
759 * fsmc_bch8_correct_data
760 * @mtd:	mtd info structure
761 * @dat:	buffer of read data
762 * @read_ecc:	ecc read from device spare area
763 * @calc_ecc:	ecc calculated from read data
764 *
765 * calc_ecc is a 104 bit information containing maximum of 8 error
766 * offset information of 13 bits each in 512 bytes of read data.
767 */
768static int fsmc_bch8_correct_data(struct nand_chip *chip, u8 *dat,
769				  u8 *read_ecc, u8 *calc_ecc)
770{
771	struct fsmc_nand_data *host = nand_to_fsmc(chip);
772	u32 err_idx[8];
773	u32 num_err, i;
774	u32 ecc1, ecc2, ecc3, ecc4;
775
776	num_err = (readl_relaxed(host->regs_va + STS) >> 10) & 0xF;
777
778	/* no bit flipping */
779	if (likely(num_err == 0))
780		return 0;
781
782	/* too many errors */
783	if (unlikely(num_err > 8)) {
784		/*
785		 * This is a temporary erase check. A newly erased page read
786		 * would result in an ecc error because the oob data is also
787		 * erased to FF and the calculated ecc for an FF data is not
788		 * FF..FF.
789		 * This is a workaround to skip performing correction in case
790		 * data is FF..FF
791		 *
792		 * Logic:
793		 * For every page, each bit written as 0 is counted until these
794		 * number of bits are greater than 8 (the maximum correction
795		 * capability of FSMC for each 512 + 13 bytes)
796		 */
797
798		int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
799		int bits_data = count_written_bits(dat, chip->ecc.size, 8);
800
801		if ((bits_ecc + bits_data) <= 8) {
802			if (bits_data)
803				memset(dat, 0xff, chip->ecc.size);
804			return bits_data;
805		}
806
807		return -EBADMSG;
808	}
809
810	/*
811	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
812	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
813	 *
814	 * calc_ecc is a 104 bit information containing maximum of 8 error
815	 * offset information of 13 bits each. calc_ecc is copied into a
816	 * u64 array and error offset indexes are populated in err_idx
817	 * array
818	 */
819	ecc1 = readl_relaxed(host->regs_va + ECC1);
820	ecc2 = readl_relaxed(host->regs_va + ECC2);
821	ecc3 = readl_relaxed(host->regs_va + ECC3);
822	ecc4 = readl_relaxed(host->regs_va + STS);
823
824	err_idx[0] = (ecc1 >> 0) & 0x1FFF;
825	err_idx[1] = (ecc1 >> 13) & 0x1FFF;
826	err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
827	err_idx[3] = (ecc2 >> 7) & 0x1FFF;
828	err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
829	err_idx[5] = (ecc3 >> 1) & 0x1FFF;
830	err_idx[6] = (ecc3 >> 14) & 0x1FFF;
831	err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
832
833	i = 0;
834	while (num_err--) {
835		err_idx[i] ^= 3;
836
837		if (err_idx[i] < chip->ecc.size * 8) {
838			int err = err_idx[i];
839
840			dat[err >> 3] ^= BIT(err & 7);
841			i++;
842		}
843	}
844	return i;
845}
846
847static bool filter(struct dma_chan *chan, void *slave)
848{
849	chan->private = slave;
850	return true;
851}
852
853static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
854				     struct fsmc_nand_data *host,
855				     struct nand_chip *nand)
856{
857	struct device_node *np = pdev->dev.of_node;
858	u32 val;
859	int ret;
860
861	nand->options = 0;
862
863	if (!of_property_read_u32(np, "bank-width", &val)) {
864		if (val == 2) {
865			nand->options |= NAND_BUSWIDTH_16;
866		} else if (val != 1) {
867			dev_err(&pdev->dev, "invalid bank-width %u\n", val);
868			return -EINVAL;
869		}
870	}
871
872	if (of_get_property(np, "nand-skip-bbtscan", NULL))
873		nand->options |= NAND_SKIP_BBTSCAN;
874
875	host->dev_timings = devm_kzalloc(&pdev->dev,
876					 sizeof(*host->dev_timings),
877					 GFP_KERNEL);
878	if (!host->dev_timings)
879		return -ENOMEM;
880
881	ret = of_property_read_u8_array(np, "timings", (u8 *)host->dev_timings,
882					sizeof(*host->dev_timings));
883	if (ret)
884		host->dev_timings = NULL;
885
886	/* Set default NAND bank to 0 */
887	host->bank = 0;
888	if (!of_property_read_u32(np, "bank", &val)) {
889		if (val > 3) {
890			dev_err(&pdev->dev, "invalid bank %u\n", val);
891			return -EINVAL;
892		}
893		host->bank = val;
894	}
895	return 0;
896}
897
898static int fsmc_nand_attach_chip(struct nand_chip *nand)
899{
900	struct mtd_info *mtd = nand_to_mtd(nand);
901	struct fsmc_nand_data *host = nand_to_fsmc(nand);
902
903	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_INVALID)
904		nand->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
905
906	if (!nand->ecc.size)
907		nand->ecc.size = 512;
908
909	if (AMBA_REV_BITS(host->pid) >= 8) {
910		nand->ecc.read_page = fsmc_read_page_hwecc;
911		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
912		nand->ecc.correct = fsmc_bch8_correct_data;
913		nand->ecc.bytes = 13;
914		nand->ecc.strength = 8;
915	}
916
917	if (AMBA_REV_BITS(host->pid) >= 8) {
918		switch (mtd->oobsize) {
919		case 16:
920		case 64:
921		case 128:
922		case 224:
923		case 256:
924			break;
925		default:
926			dev_warn(host->dev,
927				 "No oob scheme defined for oobsize %d\n",
928				 mtd->oobsize);
929			return -EINVAL;
930		}
931
932		mtd_set_ooblayout(mtd, &fsmc_ecc4_ooblayout_ops);
933
934		return 0;
935	}
936
937	switch (nand->ecc.engine_type) {
938	case NAND_ECC_ENGINE_TYPE_ON_HOST:
939		dev_info(host->dev, "Using 1-bit HW ECC scheme\n");
940		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
941		nand->ecc.correct = nand_correct_data;
942		nand->ecc.hwctl = fsmc_enable_hwecc;
943		nand->ecc.bytes = 3;
944		nand->ecc.strength = 1;
945		nand->ecc.options |= NAND_ECC_SOFT_HAMMING_SM_ORDER;
946		break;
947
948	case NAND_ECC_ENGINE_TYPE_SOFT:
949		if (nand->ecc.algo == NAND_ECC_ALGO_BCH) {
950			dev_info(host->dev,
951				 "Using 4-bit SW BCH ECC scheme\n");
952			break;
953		}
954
955	case NAND_ECC_ENGINE_TYPE_ON_DIE:
956		break;
957
958	default:
959		dev_err(host->dev, "Unsupported ECC mode!\n");
960		return -ENOTSUPP;
961	}
962
963	/*
964	 * Don't set layout for BCH4 SW ECC. This will be
965	 * generated later in nand_bch_init() later.
966	 */
967	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST) {
968		switch (mtd->oobsize) {
969		case 16:
970		case 64:
971		case 128:
972			mtd_set_ooblayout(mtd,
973					  &fsmc_ecc1_ooblayout_ops);
974			break;
975		default:
976			dev_warn(host->dev,
977				 "No oob scheme defined for oobsize %d\n",
978				 mtd->oobsize);
979			return -EINVAL;
980		}
981	}
982
983	return 0;
984}
985
986static const struct nand_controller_ops fsmc_nand_controller_ops = {
987	.attach_chip = fsmc_nand_attach_chip,
988	.exec_op = fsmc_exec_op,
989	.setup_interface = fsmc_setup_interface,
990};
991
992/**
993 * fsmc_nand_disable() - Disables the NAND bank
994 * @host: The instance to disable
995 */
996static void fsmc_nand_disable(struct fsmc_nand_data *host)
997{
998	u32 val;
999
1000	val = readl(host->regs_va + FSMC_PC);
1001	val &= ~FSMC_ENABLE;
1002	writel(val, host->regs_va + FSMC_PC);
1003}
1004
1005/*
1006 * fsmc_nand_probe - Probe function
1007 * @pdev:       platform device structure
1008 */
1009static int __init fsmc_nand_probe(struct platform_device *pdev)
1010{
1011	struct fsmc_nand_data *host;
1012	struct mtd_info *mtd;
1013	struct nand_chip *nand;
1014	struct resource *res;
1015	void __iomem *base;
1016	dma_cap_mask_t mask;
1017	int ret = 0;
1018	u32 pid;
1019	int i;
1020
1021	/* Allocate memory for the device structure (and zero it) */
1022	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
1023	if (!host)
1024		return -ENOMEM;
1025
1026	nand = &host->nand;
1027
1028	ret = fsmc_nand_probe_config_dt(pdev, host, nand);
1029	if (ret)
1030		return ret;
1031
1032	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
1033	host->data_va = devm_ioremap_resource(&pdev->dev, res);
1034	if (IS_ERR(host->data_va))
1035		return PTR_ERR(host->data_va);
1036
1037	host->data_pa = (dma_addr_t)res->start;
1038
1039	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
1040	host->addr_va = devm_ioremap_resource(&pdev->dev, res);
1041	if (IS_ERR(host->addr_va))
1042		return PTR_ERR(host->addr_va);
1043
1044	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
1045	host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
1046	if (IS_ERR(host->cmd_va))
1047		return PTR_ERR(host->cmd_va);
1048
1049	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
1050	base = devm_ioremap_resource(&pdev->dev, res);
1051	if (IS_ERR(base))
1052		return PTR_ERR(base);
1053
1054	host->regs_va = base + FSMC_NOR_REG_SIZE +
1055		(host->bank * FSMC_NAND_BANK_SZ);
1056
1057	host->clk = devm_clk_get(&pdev->dev, NULL);
1058	if (IS_ERR(host->clk)) {
1059		dev_err(&pdev->dev, "failed to fetch block clock\n");
1060		return PTR_ERR(host->clk);
1061	}
1062
1063	ret = clk_prepare_enable(host->clk);
1064	if (ret)
1065		return ret;
1066
1067	/*
1068	 * This device ID is actually a common AMBA ID as used on the
1069	 * AMBA PrimeCell bus. However it is not a PrimeCell.
1070	 */
1071	for (pid = 0, i = 0; i < 4; i++)
1072		pid |= (readl(base + resource_size(res) - 0x20 + 4 * i) &
1073			255) << (i * 8);
1074
1075	host->pid = pid;
1076
1077	dev_info(&pdev->dev,
1078		 "FSMC device partno %03x, manufacturer %02x, revision %02x, config %02x\n",
1079		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
1080		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
1081
1082	host->dev = &pdev->dev;
1083
1084	if (host->mode == USE_DMA_ACCESS)
1085		init_completion(&host->dma_access_complete);
1086
1087	/* Link all private pointers */
1088	mtd = nand_to_mtd(&host->nand);
1089	nand_set_flash_node(nand, pdev->dev.of_node);
1090
1091	mtd->dev.parent = &pdev->dev;
1092
1093	nand->badblockbits = 7;
1094
1095	if (host->mode == USE_DMA_ACCESS) {
1096		dma_cap_zero(mask);
1097		dma_cap_set(DMA_MEMCPY, mask);
1098		host->read_dma_chan = dma_request_channel(mask, filter, NULL);
1099		if (!host->read_dma_chan) {
1100			dev_err(&pdev->dev, "Unable to get read dma channel\n");
1101			ret = -ENODEV;
1102			goto disable_clk;
1103		}
1104		host->write_dma_chan = dma_request_channel(mask, filter, NULL);
1105		if (!host->write_dma_chan) {
1106			dev_err(&pdev->dev, "Unable to get write dma channel\n");
1107			ret = -ENODEV;
1108			goto release_dma_read_chan;
1109		}
1110	}
1111
1112	if (host->dev_timings) {
1113		fsmc_nand_setup(host, host->dev_timings);
1114		nand->options |= NAND_KEEP_TIMINGS;
1115	}
1116
1117	nand_controller_init(&host->base);
1118	host->base.ops = &fsmc_nand_controller_ops;
1119	nand->controller = &host->base;
1120
1121	/*
1122	 * Scan to find existence of the device
1123	 */
1124	ret = nand_scan(nand, 1);
1125	if (ret)
1126		goto release_dma_write_chan;
1127
1128	mtd->name = "nand";
1129	ret = mtd_device_register(mtd, NULL, 0);
1130	if (ret)
1131		goto cleanup_nand;
1132
1133	platform_set_drvdata(pdev, host);
1134	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
1135
1136	return 0;
1137
1138cleanup_nand:
1139	nand_cleanup(nand);
1140release_dma_write_chan:
1141	if (host->mode == USE_DMA_ACCESS)
1142		dma_release_channel(host->write_dma_chan);
1143release_dma_read_chan:
1144	if (host->mode == USE_DMA_ACCESS)
1145		dma_release_channel(host->read_dma_chan);
1146disable_clk:
1147	fsmc_nand_disable(host);
1148	clk_disable_unprepare(host->clk);
1149
1150	return ret;
1151}
1152
1153/*
1154 * Clean up routine
1155 */
1156static int fsmc_nand_remove(struct platform_device *pdev)
1157{
1158	struct fsmc_nand_data *host = platform_get_drvdata(pdev);
1159
1160	if (host) {
1161		struct nand_chip *chip = &host->nand;
1162		int ret;
1163
1164		ret = mtd_device_unregister(nand_to_mtd(chip));
1165		WARN_ON(ret);
1166		nand_cleanup(chip);
1167		fsmc_nand_disable(host);
1168
1169		if (host->mode == USE_DMA_ACCESS) {
1170			dma_release_channel(host->write_dma_chan);
1171			dma_release_channel(host->read_dma_chan);
1172		}
1173		clk_disable_unprepare(host->clk);
1174	}
1175
1176	return 0;
1177}
1178
1179#ifdef CONFIG_PM_SLEEP
1180static int fsmc_nand_suspend(struct device *dev)
1181{
1182	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1183
1184	if (host)
1185		clk_disable_unprepare(host->clk);
1186
1187	return 0;
1188}
1189
1190static int fsmc_nand_resume(struct device *dev)
1191{
1192	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1193	int ret;
1194
1195	if (host) {
1196		ret = clk_prepare_enable(host->clk);
1197		if (ret) {
1198			dev_err(dev, "failed to enable clk\n");
1199			return ret;
1200		}
1201		if (host->dev_timings)
1202			fsmc_nand_setup(host, host->dev_timings);
1203		nand_reset(&host->nand, 0);
1204	}
1205
1206	return 0;
1207}
1208#endif
1209
1210static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
1211
1212static const struct of_device_id fsmc_nand_id_table[] = {
1213	{ .compatible = "st,spear600-fsmc-nand" },
1214	{ .compatible = "stericsson,fsmc-nand" },
1215	{}
1216};
1217MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
1218
1219static struct platform_driver fsmc_nand_driver = {
1220	.remove = fsmc_nand_remove,
1221	.driver = {
1222		.name = "fsmc-nand",
1223		.of_match_table = fsmc_nand_id_table,
1224		.pm = &fsmc_nand_pm_ops,
1225	},
1226};
1227
1228module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
1229
1230MODULE_LICENSE("GPL v2");
1231MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
1232MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");
1233