xref: /openbmc/linux/drivers/mtd/nand/raw/fsmc_nand.c (revision fb574682)
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/dmaengine.h>
19 #include <linux/dma-direction.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/err.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/resource.h>
25 #include <linux/sched.h>
26 #include <linux/types.h>
27 #include <linux/mtd/mtd.h>
28 #include <linux/mtd/rawnand.h>
29 #include <linux/mtd/nand_ecc.h>
30 #include <linux/platform_device.h>
31 #include <linux/of.h>
32 #include <linux/mtd/partitions.h>
33 #include <linux/io.h>
34 #include <linux/slab.h>
35 #include <linux/amba/bus.h>
36 #include <mtd/mtd-abi.h>
37 
38 /* fsmc controller registers for NOR flash */
39 #define CTRL			0x0
40 	/* ctrl register definitions */
41 	#define BANK_ENABLE		BIT(0)
42 	#define MUXED			BIT(1)
43 	#define NOR_DEV			(2 << 2)
44 	#define WIDTH_16		BIT(4)
45 	#define RSTPWRDWN		BIT(6)
46 	#define WPROT			BIT(7)
47 	#define WRT_ENABLE		BIT(12)
48 	#define WAIT_ENB		BIT(13)
49 
50 #define CTRL_TIM		0x4
51 	/* ctrl_tim register definitions */
52 
53 #define FSMC_NOR_BANK_SZ	0x8
54 #define FSMC_NOR_REG_SIZE	0x40
55 
56 #define FSMC_NOR_REG(base, bank, reg)	((base) +			\
57 					 (FSMC_NOR_BANK_SZ * (bank)) +	\
58 					 (reg))
59 
60 /* fsmc controller registers for NAND flash */
61 #define FSMC_PC			0x00
62 	/* pc register definitions */
63 	#define FSMC_RESET		BIT(0)
64 	#define FSMC_WAITON		BIT(1)
65 	#define FSMC_ENABLE		BIT(2)
66 	#define FSMC_DEVTYPE_NAND	BIT(3)
67 	#define FSMC_DEVWID_16		BIT(4)
68 	#define FSMC_ECCEN		BIT(6)
69 	#define FSMC_ECCPLEN_256	BIT(7)
70 	#define FSMC_TCLR_SHIFT		(9)
71 	#define FSMC_TCLR_MASK		(0xF)
72 	#define FSMC_TAR_SHIFT		(13)
73 	#define FSMC_TAR_MASK		(0xF)
74 #define STS			0x04
75 	/* sts register definitions */
76 	#define FSMC_CODE_RDY		BIT(15)
77 #define COMM			0x08
78 	/* comm register definitions */
79 	#define FSMC_TSET_SHIFT		0
80 	#define FSMC_TSET_MASK		0xFF
81 	#define FSMC_TWAIT_SHIFT	8
82 	#define FSMC_TWAIT_MASK		0xFF
83 	#define FSMC_THOLD_SHIFT	16
84 	#define FSMC_THOLD_MASK		0xFF
85 	#define FSMC_THIZ_SHIFT		24
86 	#define FSMC_THIZ_MASK		0xFF
87 #define ATTRIB			0x0C
88 #define IOATA			0x10
89 #define ECC1			0x14
90 #define ECC2			0x18
91 #define ECC3			0x1C
92 #define FSMC_NAND_BANK_SZ	0x20
93 
94 #define FSMC_BUSY_WAIT_TIMEOUT	(1 * HZ)
95 
96 struct fsmc_nand_timings {
97 	u8 tclr;
98 	u8 tar;
99 	u8 thiz;
100 	u8 thold;
101 	u8 twait;
102 	u8 tset;
103 };
104 
105 enum access_mode {
106 	USE_DMA_ACCESS = 1,
107 	USE_WORD_ACCESS,
108 };
109 
110 /**
111  * struct fsmc_nand_data - structure for FSMC NAND device state
112  *
113  * @base:		Inherit from the nand_controller struct
114  * @pid:		Part ID on the AMBA PrimeCell format
115  * @nand:		Chip related info for a NAND flash.
116  *
117  * @bank:		Bank number for probed device.
118  * @dev:		Parent device
119  * @mode:		Access mode
120  * @clk:		Clock structure for FSMC.
121  *
122  * @read_dma_chan:	DMA channel for read access
123  * @write_dma_chan:	DMA channel for write access to NAND
124  * @dma_access_complete: Completion structure
125  *
126  * @dev_timings:	NAND timings
127  *
128  * @data_pa:		NAND Physical port for Data.
129  * @data_va:		NAND port for Data.
130  * @cmd_va:		NAND port for Command.
131  * @addr_va:		NAND port for Address.
132  * @regs_va:		Registers base address for a given bank.
133  */
134 struct fsmc_nand_data {
135 	struct nand_controller	base;
136 	u32			pid;
137 	struct nand_chip	nand;
138 
139 	unsigned int		bank;
140 	struct device		*dev;
141 	enum access_mode	mode;
142 	struct clk		*clk;
143 
144 	/* DMA related objects */
145 	struct dma_chan		*read_dma_chan;
146 	struct dma_chan		*write_dma_chan;
147 	struct completion	dma_access_complete;
148 
149 	struct fsmc_nand_timings *dev_timings;
150 
151 	dma_addr_t		data_pa;
152 	void __iomem		*data_va;
153 	void __iomem		*cmd_va;
154 	void __iomem		*addr_va;
155 	void __iomem		*regs_va;
156 };
157 
158 static int fsmc_ecc1_ooblayout_ecc(struct mtd_info *mtd, int section,
159 				   struct mtd_oob_region *oobregion)
160 {
161 	struct nand_chip *chip = mtd_to_nand(mtd);
162 
163 	if (section >= chip->ecc.steps)
164 		return -ERANGE;
165 
166 	oobregion->offset = (section * 16) + 2;
167 	oobregion->length = 3;
168 
169 	return 0;
170 }
171 
172 static int fsmc_ecc1_ooblayout_free(struct mtd_info *mtd, int section,
173 				    struct mtd_oob_region *oobregion)
174 {
175 	struct nand_chip *chip = mtd_to_nand(mtd);
176 
177 	if (section >= chip->ecc.steps)
178 		return -ERANGE;
179 
180 	oobregion->offset = (section * 16) + 8;
181 
182 	if (section < chip->ecc.steps - 1)
183 		oobregion->length = 8;
184 	else
185 		oobregion->length = mtd->oobsize - oobregion->offset;
186 
187 	return 0;
188 }
189 
190 static const struct mtd_ooblayout_ops fsmc_ecc1_ooblayout_ops = {
191 	.ecc = fsmc_ecc1_ooblayout_ecc,
192 	.free = fsmc_ecc1_ooblayout_free,
193 };
194 
195 /*
196  * ECC placement definitions in oobfree type format.
197  * There are 13 bytes of ecc for every 512 byte block and it has to be read
198  * consecutively and immediately after the 512 byte data block for hardware to
199  * generate the error bit offsets in 512 byte data.
200  */
201 static int fsmc_ecc4_ooblayout_ecc(struct mtd_info *mtd, int section,
202 				   struct mtd_oob_region *oobregion)
203 {
204 	struct nand_chip *chip = mtd_to_nand(mtd);
205 
206 	if (section >= chip->ecc.steps)
207 		return -ERANGE;
208 
209 	oobregion->length = chip->ecc.bytes;
210 
211 	if (!section && mtd->writesize <= 512)
212 		oobregion->offset = 0;
213 	else
214 		oobregion->offset = (section * 16) + 2;
215 
216 	return 0;
217 }
218 
219 static int fsmc_ecc4_ooblayout_free(struct mtd_info *mtd, int section,
220 				    struct mtd_oob_region *oobregion)
221 {
222 	struct nand_chip *chip = mtd_to_nand(mtd);
223 
224 	if (section >= chip->ecc.steps)
225 		return -ERANGE;
226 
227 	oobregion->offset = (section * 16) + 15;
228 
229 	if (section < chip->ecc.steps - 1)
230 		oobregion->length = 3;
231 	else
232 		oobregion->length = mtd->oobsize - oobregion->offset;
233 
234 	return 0;
235 }
236 
237 static const struct mtd_ooblayout_ops fsmc_ecc4_ooblayout_ops = {
238 	.ecc = fsmc_ecc4_ooblayout_ecc,
239 	.free = fsmc_ecc4_ooblayout_free,
240 };
241 
242 static inline struct fsmc_nand_data *nand_to_fsmc(struct nand_chip *chip)
243 {
244 	return container_of(chip, struct fsmc_nand_data, nand);
245 }
246 
247 /*
248  * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
249  *
250  * This routine initializes timing parameters related to NAND memory access in
251  * FSMC registers
252  */
253 static void fsmc_nand_setup(struct fsmc_nand_data *host,
254 			    struct fsmc_nand_timings *tims)
255 {
256 	u32 value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
257 	u32 tclr, tar, thiz, thold, twait, tset;
258 
259 	tclr = (tims->tclr & FSMC_TCLR_MASK) << FSMC_TCLR_SHIFT;
260 	tar = (tims->tar & FSMC_TAR_MASK) << FSMC_TAR_SHIFT;
261 	thiz = (tims->thiz & FSMC_THIZ_MASK) << FSMC_THIZ_SHIFT;
262 	thold = (tims->thold & FSMC_THOLD_MASK) << FSMC_THOLD_SHIFT;
263 	twait = (tims->twait & FSMC_TWAIT_MASK) << FSMC_TWAIT_SHIFT;
264 	tset = (tims->tset & FSMC_TSET_MASK) << FSMC_TSET_SHIFT;
265 
266 	if (host->nand.options & NAND_BUSWIDTH_16)
267 		value |= FSMC_DEVWID_16;
268 
269 	writel_relaxed(value | tclr | tar, host->regs_va + FSMC_PC);
270 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + COMM);
271 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + ATTRIB);
272 }
273 
274 static int fsmc_calc_timings(struct fsmc_nand_data *host,
275 			     const struct nand_sdr_timings *sdrt,
276 			     struct fsmc_nand_timings *tims)
277 {
278 	unsigned long hclk = clk_get_rate(host->clk);
279 	unsigned long hclkn = NSEC_PER_SEC / hclk;
280 	u32 thiz, thold, twait, tset;
281 
282 	if (sdrt->tRC_min < 30000)
283 		return -EOPNOTSUPP;
284 
285 	tims->tar = DIV_ROUND_UP(sdrt->tAR_min / 1000, hclkn) - 1;
286 	if (tims->tar > FSMC_TAR_MASK)
287 		tims->tar = FSMC_TAR_MASK;
288 	tims->tclr = DIV_ROUND_UP(sdrt->tCLR_min / 1000, hclkn) - 1;
289 	if (tims->tclr > FSMC_TCLR_MASK)
290 		tims->tclr = FSMC_TCLR_MASK;
291 
292 	thiz = sdrt->tCS_min - sdrt->tWP_min;
293 	tims->thiz = DIV_ROUND_UP(thiz / 1000, hclkn);
294 
295 	thold = sdrt->tDH_min;
296 	if (thold < sdrt->tCH_min)
297 		thold = sdrt->tCH_min;
298 	if (thold < sdrt->tCLH_min)
299 		thold = sdrt->tCLH_min;
300 	if (thold < sdrt->tWH_min)
301 		thold = sdrt->tWH_min;
302 	if (thold < sdrt->tALH_min)
303 		thold = sdrt->tALH_min;
304 	if (thold < sdrt->tREH_min)
305 		thold = sdrt->tREH_min;
306 	tims->thold = DIV_ROUND_UP(thold / 1000, hclkn);
307 	if (tims->thold == 0)
308 		tims->thold = 1;
309 	else if (tims->thold > FSMC_THOLD_MASK)
310 		tims->thold = FSMC_THOLD_MASK;
311 
312 	twait = max(sdrt->tRP_min, sdrt->tWP_min);
313 	tims->twait = DIV_ROUND_UP(twait / 1000, hclkn) - 1;
314 	if (tims->twait == 0)
315 		tims->twait = 1;
316 	else if (tims->twait > FSMC_TWAIT_MASK)
317 		tims->twait = FSMC_TWAIT_MASK;
318 
319 	tset = max(sdrt->tCS_min - sdrt->tWP_min,
320 		   sdrt->tCEA_max - sdrt->tREA_max);
321 	tims->tset = DIV_ROUND_UP(tset / 1000, hclkn) - 1;
322 	if (tims->tset == 0)
323 		tims->tset = 1;
324 	else if (tims->tset > FSMC_TSET_MASK)
325 		tims->tset = FSMC_TSET_MASK;
326 
327 	return 0;
328 }
329 
330 static int fsmc_setup_data_interface(struct nand_chip *nand, int csline,
331 				     const struct nand_data_interface *conf)
332 {
333 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
334 	struct fsmc_nand_timings tims;
335 	const struct nand_sdr_timings *sdrt;
336 	int ret;
337 
338 	sdrt = nand_get_sdr_timings(conf);
339 	if (IS_ERR(sdrt))
340 		return PTR_ERR(sdrt);
341 
342 	ret = fsmc_calc_timings(host, sdrt, &tims);
343 	if (ret)
344 		return ret;
345 
346 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
347 		return 0;
348 
349 	fsmc_nand_setup(host, &tims);
350 
351 	return 0;
352 }
353 
354 /*
355  * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
356  */
357 static void fsmc_enable_hwecc(struct nand_chip *chip, int mode)
358 {
359 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
360 
361 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCPLEN_256,
362 		       host->regs_va + FSMC_PC);
363 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCEN,
364 		       host->regs_va + FSMC_PC);
365 	writel_relaxed(readl(host->regs_va + FSMC_PC) | FSMC_ECCEN,
366 		       host->regs_va + FSMC_PC);
367 }
368 
369 /*
370  * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
371  * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
372  * max of 8-bits)
373  */
374 static int fsmc_read_hwecc_ecc4(struct nand_chip *chip, const u8 *data,
375 				u8 *ecc)
376 {
377 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
378 	u32 ecc_tmp;
379 	unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;
380 
381 	do {
382 		if (readl_relaxed(host->regs_va + STS) & FSMC_CODE_RDY)
383 			break;
384 
385 		cond_resched();
386 	} while (!time_after_eq(jiffies, deadline));
387 
388 	if (time_after_eq(jiffies, deadline)) {
389 		dev_err(host->dev, "calculate ecc timed out\n");
390 		return -ETIMEDOUT;
391 	}
392 
393 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
394 	ecc[0] = ecc_tmp;
395 	ecc[1] = ecc_tmp >> 8;
396 	ecc[2] = ecc_tmp >> 16;
397 	ecc[3] = ecc_tmp >> 24;
398 
399 	ecc_tmp = readl_relaxed(host->regs_va + ECC2);
400 	ecc[4] = ecc_tmp;
401 	ecc[5] = ecc_tmp >> 8;
402 	ecc[6] = ecc_tmp >> 16;
403 	ecc[7] = ecc_tmp >> 24;
404 
405 	ecc_tmp = readl_relaxed(host->regs_va + ECC3);
406 	ecc[8] = ecc_tmp;
407 	ecc[9] = ecc_tmp >> 8;
408 	ecc[10] = ecc_tmp >> 16;
409 	ecc[11] = ecc_tmp >> 24;
410 
411 	ecc_tmp = readl_relaxed(host->regs_va + STS);
412 	ecc[12] = ecc_tmp >> 16;
413 
414 	return 0;
415 }
416 
417 /*
418  * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
419  * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
420  * max of 1-bit)
421  */
422 static int fsmc_read_hwecc_ecc1(struct nand_chip *chip, const u8 *data,
423 				u8 *ecc)
424 {
425 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
426 	u32 ecc_tmp;
427 
428 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
429 	ecc[0] = ecc_tmp;
430 	ecc[1] = ecc_tmp >> 8;
431 	ecc[2] = ecc_tmp >> 16;
432 
433 	return 0;
434 }
435 
436 /* Count the number of 0's in buff upto a max of max_bits */
437 static int count_written_bits(u8 *buff, int size, int max_bits)
438 {
439 	int k, written_bits = 0;
440 
441 	for (k = 0; k < size; k++) {
442 		written_bits += hweight8(~buff[k]);
443 		if (written_bits > max_bits)
444 			break;
445 	}
446 
447 	return written_bits;
448 }
449 
450 static void dma_complete(void *param)
451 {
452 	struct fsmc_nand_data *host = param;
453 
454 	complete(&host->dma_access_complete);
455 }
456 
457 static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
458 		    enum dma_data_direction direction)
459 {
460 	struct dma_chan *chan;
461 	struct dma_device *dma_dev;
462 	struct dma_async_tx_descriptor *tx;
463 	dma_addr_t dma_dst, dma_src, dma_addr;
464 	dma_cookie_t cookie;
465 	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
466 	int ret;
467 	unsigned long time_left;
468 
469 	if (direction == DMA_TO_DEVICE)
470 		chan = host->write_dma_chan;
471 	else if (direction == DMA_FROM_DEVICE)
472 		chan = host->read_dma_chan;
473 	else
474 		return -EINVAL;
475 
476 	dma_dev = chan->device;
477 	dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
478 
479 	if (direction == DMA_TO_DEVICE) {
480 		dma_src = dma_addr;
481 		dma_dst = host->data_pa;
482 	} else {
483 		dma_src = host->data_pa;
484 		dma_dst = dma_addr;
485 	}
486 
487 	tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
488 			len, flags);
489 	if (!tx) {
490 		dev_err(host->dev, "device_prep_dma_memcpy error\n");
491 		ret = -EIO;
492 		goto unmap_dma;
493 	}
494 
495 	tx->callback = dma_complete;
496 	tx->callback_param = host;
497 	cookie = tx->tx_submit(tx);
498 
499 	ret = dma_submit_error(cookie);
500 	if (ret) {
501 		dev_err(host->dev, "dma_submit_error %d\n", cookie);
502 		goto unmap_dma;
503 	}
504 
505 	dma_async_issue_pending(chan);
506 
507 	time_left =
508 	wait_for_completion_timeout(&host->dma_access_complete,
509 				    msecs_to_jiffies(3000));
510 	if (time_left == 0) {
511 		dmaengine_terminate_all(chan);
512 		dev_err(host->dev, "wait_for_completion_timeout\n");
513 		ret = -ETIMEDOUT;
514 		goto unmap_dma;
515 	}
516 
517 	ret = 0;
518 
519 unmap_dma:
520 	dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
521 
522 	return ret;
523 }
524 
525 /*
526  * fsmc_write_buf - write buffer to chip
527  * @host:	FSMC NAND controller
528  * @buf:	data buffer
529  * @len:	number of bytes to write
530  */
531 static void fsmc_write_buf(struct fsmc_nand_data *host, const u8 *buf,
532 			   int len)
533 {
534 	int i;
535 
536 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
537 	    IS_ALIGNED(len, sizeof(u32))) {
538 		u32 *p = (u32 *)buf;
539 
540 		len = len >> 2;
541 		for (i = 0; i < len; i++)
542 			writel_relaxed(p[i], host->data_va);
543 	} else {
544 		for (i = 0; i < len; i++)
545 			writeb_relaxed(buf[i], host->data_va);
546 	}
547 }
548 
549 /*
550  * fsmc_read_buf - read chip data into buffer
551  * @host:	FSMC NAND controller
552  * @buf:	buffer to store date
553  * @len:	number of bytes to read
554  */
555 static void fsmc_read_buf(struct fsmc_nand_data *host, u8 *buf, int len)
556 {
557 	int i;
558 
559 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
560 	    IS_ALIGNED(len, sizeof(u32))) {
561 		u32 *p = (u32 *)buf;
562 
563 		len = len >> 2;
564 		for (i = 0; i < len; i++)
565 			p[i] = readl_relaxed(host->data_va);
566 	} else {
567 		for (i = 0; i < len; i++)
568 			buf[i] = readb_relaxed(host->data_va);
569 	}
570 }
571 
572 /*
573  * fsmc_read_buf_dma - read chip data into buffer
574  * @host:	FSMC NAND controller
575  * @buf:	buffer to store date
576  * @len:	number of bytes to read
577  */
578 static void fsmc_read_buf_dma(struct fsmc_nand_data *host, u8 *buf,
579 			      int len)
580 {
581 	dma_xfer(host, buf, len, DMA_FROM_DEVICE);
582 }
583 
584 /*
585  * fsmc_write_buf_dma - write buffer to chip
586  * @host:	FSMC NAND controller
587  * @buf:	data buffer
588  * @len:	number of bytes to write
589  */
590 static void fsmc_write_buf_dma(struct fsmc_nand_data *host, const u8 *buf,
591 			       int len)
592 {
593 	dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
594 }
595 
596 /*
597  * fsmc_exec_op - hook called by the core to execute NAND operations
598  *
599  * This controller is simple enough and thus does not need to use the parser
600  * provided by the core, instead, handle every situation here.
601  */
602 static int fsmc_exec_op(struct nand_chip *chip, const struct nand_operation *op,
603 			bool check_only)
604 {
605 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
606 	const struct nand_op_instr *instr = NULL;
607 	int ret = 0;
608 	unsigned int op_id;
609 	int i;
610 
611 	if (check_only)
612 		return 0;
613 
614 	pr_debug("Executing operation [%d instructions]:\n", op->ninstrs);
615 
616 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
617 		instr = &op->instrs[op_id];
618 
619 		nand_op_trace("  ", instr);
620 
621 		switch (instr->type) {
622 		case NAND_OP_CMD_INSTR:
623 			writeb_relaxed(instr->ctx.cmd.opcode, host->cmd_va);
624 			break;
625 
626 		case NAND_OP_ADDR_INSTR:
627 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
628 				writeb_relaxed(instr->ctx.addr.addrs[i],
629 					       host->addr_va);
630 			break;
631 
632 		case NAND_OP_DATA_IN_INSTR:
633 			if (host->mode == USE_DMA_ACCESS)
634 				fsmc_read_buf_dma(host, instr->ctx.data.buf.in,
635 						  instr->ctx.data.len);
636 			else
637 				fsmc_read_buf(host, instr->ctx.data.buf.in,
638 					      instr->ctx.data.len);
639 			break;
640 
641 		case NAND_OP_DATA_OUT_INSTR:
642 			if (host->mode == USE_DMA_ACCESS)
643 				fsmc_write_buf_dma(host,
644 						   instr->ctx.data.buf.out,
645 						   instr->ctx.data.len);
646 			else
647 				fsmc_write_buf(host, instr->ctx.data.buf.out,
648 					       instr->ctx.data.len);
649 			break;
650 
651 		case NAND_OP_WAITRDY_INSTR:
652 			ret = nand_soft_waitrdy(chip,
653 						instr->ctx.waitrdy.timeout_ms);
654 			break;
655 		}
656 	}
657 
658 	return ret;
659 }
660 
661 /*
662  * fsmc_read_page_hwecc
663  * @chip:	nand chip info structure
664  * @buf:	buffer to store read data
665  * @oob_required:	caller expects OOB data read to chip->oob_poi
666  * @page:	page number to read
667  *
668  * This routine is needed for fsmc version 8 as reading from NAND chip has to be
669  * performed in a strict sequence as follows:
670  * data(512 byte) -> ecc(13 byte)
671  * After this read, fsmc hardware generates and reports error data bits(up to a
672  * max of 8 bits)
673  */
674 static int fsmc_read_page_hwecc(struct nand_chip *chip, u8 *buf,
675 				int oob_required, int page)
676 {
677 	struct mtd_info *mtd = nand_to_mtd(chip);
678 	int i, j, s, stat, eccsize = chip->ecc.size;
679 	int eccbytes = chip->ecc.bytes;
680 	int eccsteps = chip->ecc.steps;
681 	u8 *p = buf;
682 	u8 *ecc_calc = chip->ecc.calc_buf;
683 	u8 *ecc_code = chip->ecc.code_buf;
684 	int off, len, ret, group = 0;
685 	/*
686 	 * ecc_oob is intentionally taken as u16. In 16bit devices, we
687 	 * end up reading 14 bytes (7 words) from oob. The local array is
688 	 * to maintain word alignment
689 	 */
690 	u16 ecc_oob[7];
691 	u8 *oob = (u8 *)&ecc_oob[0];
692 	unsigned int max_bitflips = 0;
693 
694 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
695 		nand_read_page_op(chip, page, s * eccsize, NULL, 0);
696 		chip->ecc.hwctl(chip, NAND_ECC_READ);
697 		ret = nand_read_data_op(chip, p, eccsize, false, false);
698 		if (ret)
699 			return ret;
700 
701 		for (j = 0; j < eccbytes;) {
702 			struct mtd_oob_region oobregion;
703 
704 			ret = mtd_ooblayout_ecc(mtd, group++, &oobregion);
705 			if (ret)
706 				return ret;
707 
708 			off = oobregion.offset;
709 			len = oobregion.length;
710 
711 			/*
712 			 * length is intentionally kept a higher multiple of 2
713 			 * to read at least 13 bytes even in case of 16 bit NAND
714 			 * devices
715 			 */
716 			if (chip->options & NAND_BUSWIDTH_16)
717 				len = roundup(len, 2);
718 
719 			nand_read_oob_op(chip, page, off, oob + j, len);
720 			j += len;
721 		}
722 
723 		memcpy(&ecc_code[i], oob, chip->ecc.bytes);
724 		chip->ecc.calculate(chip, p, &ecc_calc[i]);
725 
726 		stat = chip->ecc.correct(chip, p, &ecc_code[i], &ecc_calc[i]);
727 		if (stat < 0) {
728 			mtd->ecc_stats.failed++;
729 		} else {
730 			mtd->ecc_stats.corrected += stat;
731 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
732 		}
733 	}
734 
735 	return max_bitflips;
736 }
737 
738 /*
739  * fsmc_bch8_correct_data
740  * @mtd:	mtd info structure
741  * @dat:	buffer of read data
742  * @read_ecc:	ecc read from device spare area
743  * @calc_ecc:	ecc calculated from read data
744  *
745  * calc_ecc is a 104 bit information containing maximum of 8 error
746  * offset information of 13 bits each in 512 bytes of read data.
747  */
748 static int fsmc_bch8_correct_data(struct nand_chip *chip, u8 *dat,
749 				  u8 *read_ecc, u8 *calc_ecc)
750 {
751 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
752 	u32 err_idx[8];
753 	u32 num_err, i;
754 	u32 ecc1, ecc2, ecc3, ecc4;
755 
756 	num_err = (readl_relaxed(host->regs_va + STS) >> 10) & 0xF;
757 
758 	/* no bit flipping */
759 	if (likely(num_err == 0))
760 		return 0;
761 
762 	/* too many errors */
763 	if (unlikely(num_err > 8)) {
764 		/*
765 		 * This is a temporary erase check. A newly erased page read
766 		 * would result in an ecc error because the oob data is also
767 		 * erased to FF and the calculated ecc for an FF data is not
768 		 * FF..FF.
769 		 * This is a workaround to skip performing correction in case
770 		 * data is FF..FF
771 		 *
772 		 * Logic:
773 		 * For every page, each bit written as 0 is counted until these
774 		 * number of bits are greater than 8 (the maximum correction
775 		 * capability of FSMC for each 512 + 13 bytes)
776 		 */
777 
778 		int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
779 		int bits_data = count_written_bits(dat, chip->ecc.size, 8);
780 
781 		if ((bits_ecc + bits_data) <= 8) {
782 			if (bits_data)
783 				memset(dat, 0xff, chip->ecc.size);
784 			return bits_data;
785 		}
786 
787 		return -EBADMSG;
788 	}
789 
790 	/*
791 	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
792 	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
793 	 *
794 	 * calc_ecc is a 104 bit information containing maximum of 8 error
795 	 * offset information of 13 bits each. calc_ecc is copied into a
796 	 * u64 array and error offset indexes are populated in err_idx
797 	 * array
798 	 */
799 	ecc1 = readl_relaxed(host->regs_va + ECC1);
800 	ecc2 = readl_relaxed(host->regs_va + ECC2);
801 	ecc3 = readl_relaxed(host->regs_va + ECC3);
802 	ecc4 = readl_relaxed(host->regs_va + STS);
803 
804 	err_idx[0] = (ecc1 >> 0) & 0x1FFF;
805 	err_idx[1] = (ecc1 >> 13) & 0x1FFF;
806 	err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
807 	err_idx[3] = (ecc2 >> 7) & 0x1FFF;
808 	err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
809 	err_idx[5] = (ecc3 >> 1) & 0x1FFF;
810 	err_idx[6] = (ecc3 >> 14) & 0x1FFF;
811 	err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
812 
813 	i = 0;
814 	while (num_err--) {
815 		err_idx[i] ^= 3;
816 
817 		if (err_idx[i] < chip->ecc.size * 8) {
818 			int err = err_idx[i];
819 
820 			dat[err >> 3] ^= BIT(err & 7);
821 			i++;
822 		}
823 	}
824 	return i;
825 }
826 
827 static bool filter(struct dma_chan *chan, void *slave)
828 {
829 	chan->private = slave;
830 	return true;
831 }
832 
833 static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
834 				     struct fsmc_nand_data *host,
835 				     struct nand_chip *nand)
836 {
837 	struct device_node *np = pdev->dev.of_node;
838 	u32 val;
839 	int ret;
840 
841 	nand->options = 0;
842 
843 	if (!of_property_read_u32(np, "bank-width", &val)) {
844 		if (val == 2) {
845 			nand->options |= NAND_BUSWIDTH_16;
846 		} else if (val != 1) {
847 			dev_err(&pdev->dev, "invalid bank-width %u\n", val);
848 			return -EINVAL;
849 		}
850 	}
851 
852 	if (of_get_property(np, "nand-skip-bbtscan", NULL))
853 		nand->options |= NAND_SKIP_BBTSCAN;
854 
855 	host->dev_timings = devm_kzalloc(&pdev->dev,
856 					 sizeof(*host->dev_timings),
857 					 GFP_KERNEL);
858 	if (!host->dev_timings)
859 		return -ENOMEM;
860 
861 	ret = of_property_read_u8_array(np, "timings", (u8 *)host->dev_timings,
862 					sizeof(*host->dev_timings));
863 	if (ret)
864 		host->dev_timings = NULL;
865 
866 	/* Set default NAND bank to 0 */
867 	host->bank = 0;
868 	if (!of_property_read_u32(np, "bank", &val)) {
869 		if (val > 3) {
870 			dev_err(&pdev->dev, "invalid bank %u\n", val);
871 			return -EINVAL;
872 		}
873 		host->bank = val;
874 	}
875 	return 0;
876 }
877 
878 static int fsmc_nand_attach_chip(struct nand_chip *nand)
879 {
880 	struct mtd_info *mtd = nand_to_mtd(nand);
881 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
882 
883 	if (AMBA_REV_BITS(host->pid) >= 8) {
884 		switch (mtd->oobsize) {
885 		case 16:
886 		case 64:
887 		case 128:
888 		case 224:
889 		case 256:
890 			break;
891 		default:
892 			dev_warn(host->dev,
893 				 "No oob scheme defined for oobsize %d\n",
894 				 mtd->oobsize);
895 			return -EINVAL;
896 		}
897 
898 		mtd_set_ooblayout(mtd, &fsmc_ecc4_ooblayout_ops);
899 
900 		return 0;
901 	}
902 
903 	switch (nand->ecc.mode) {
904 	case NAND_ECC_HW:
905 		dev_info(host->dev, "Using 1-bit HW ECC scheme\n");
906 		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
907 		nand->ecc.correct = nand_correct_data;
908 		nand->ecc.bytes = 3;
909 		nand->ecc.strength = 1;
910 		nand->ecc.options |= NAND_ECC_SOFT_HAMMING_SM_ORDER;
911 		break;
912 
913 	case NAND_ECC_SOFT:
914 		if (nand->ecc.algo == NAND_ECC_BCH) {
915 			dev_info(host->dev,
916 				 "Using 4-bit SW BCH ECC scheme\n");
917 			break;
918 		}
919 
920 	case NAND_ECC_ON_DIE:
921 		break;
922 
923 	default:
924 		dev_err(host->dev, "Unsupported ECC mode!\n");
925 		return -ENOTSUPP;
926 	}
927 
928 	/*
929 	 * Don't set layout for BCH4 SW ECC. This will be
930 	 * generated later in nand_bch_init() later.
931 	 */
932 	if (nand->ecc.mode == NAND_ECC_HW) {
933 		switch (mtd->oobsize) {
934 		case 16:
935 		case 64:
936 		case 128:
937 			mtd_set_ooblayout(mtd,
938 					  &fsmc_ecc1_ooblayout_ops);
939 			break;
940 		default:
941 			dev_warn(host->dev,
942 				 "No oob scheme defined for oobsize %d\n",
943 				 mtd->oobsize);
944 			return -EINVAL;
945 		}
946 	}
947 
948 	return 0;
949 }
950 
951 static const struct nand_controller_ops fsmc_nand_controller_ops = {
952 	.attach_chip = fsmc_nand_attach_chip,
953 	.exec_op = fsmc_exec_op,
954 	.setup_data_interface = fsmc_setup_data_interface,
955 };
956 
957 /**
958  * fsmc_nand_disable() - Disables the NAND bank
959  * @host: The instance to disable
960  */
961 static void fsmc_nand_disable(struct fsmc_nand_data *host)
962 {
963 	u32 val;
964 
965 	val = readl(host->regs_va + FSMC_PC);
966 	val &= ~FSMC_ENABLE;
967 	writel(val, host->regs_va + FSMC_PC);
968 }
969 
970 /*
971  * fsmc_nand_probe - Probe function
972  * @pdev:       platform device structure
973  */
974 static int __init fsmc_nand_probe(struct platform_device *pdev)
975 {
976 	struct fsmc_nand_data *host;
977 	struct mtd_info *mtd;
978 	struct nand_chip *nand;
979 	struct resource *res;
980 	void __iomem *base;
981 	dma_cap_mask_t mask;
982 	int ret = 0;
983 	u32 pid;
984 	int i;
985 
986 	/* Allocate memory for the device structure (and zero it) */
987 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
988 	if (!host)
989 		return -ENOMEM;
990 
991 	nand = &host->nand;
992 
993 	ret = fsmc_nand_probe_config_dt(pdev, host, nand);
994 	if (ret)
995 		return ret;
996 
997 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
998 	host->data_va = devm_ioremap_resource(&pdev->dev, res);
999 	if (IS_ERR(host->data_va))
1000 		return PTR_ERR(host->data_va);
1001 
1002 	host->data_pa = (dma_addr_t)res->start;
1003 
1004 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
1005 	host->addr_va = devm_ioremap_resource(&pdev->dev, res);
1006 	if (IS_ERR(host->addr_va))
1007 		return PTR_ERR(host->addr_va);
1008 
1009 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
1010 	host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
1011 	if (IS_ERR(host->cmd_va))
1012 		return PTR_ERR(host->cmd_va);
1013 
1014 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
1015 	base = devm_ioremap_resource(&pdev->dev, res);
1016 	if (IS_ERR(base))
1017 		return PTR_ERR(base);
1018 
1019 	host->regs_va = base + FSMC_NOR_REG_SIZE +
1020 		(host->bank * FSMC_NAND_BANK_SZ);
1021 
1022 	host->clk = devm_clk_get(&pdev->dev, NULL);
1023 	if (IS_ERR(host->clk)) {
1024 		dev_err(&pdev->dev, "failed to fetch block clock\n");
1025 		return PTR_ERR(host->clk);
1026 	}
1027 
1028 	ret = clk_prepare_enable(host->clk);
1029 	if (ret)
1030 		return ret;
1031 
1032 	/*
1033 	 * This device ID is actually a common AMBA ID as used on the
1034 	 * AMBA PrimeCell bus. However it is not a PrimeCell.
1035 	 */
1036 	for (pid = 0, i = 0; i < 4; i++)
1037 		pid |= (readl(base + resource_size(res) - 0x20 + 4 * i) &
1038 			255) << (i * 8);
1039 
1040 	host->pid = pid;
1041 
1042 	dev_info(&pdev->dev,
1043 		 "FSMC device partno %03x, manufacturer %02x, revision %02x, config %02x\n",
1044 		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
1045 		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
1046 
1047 	host->dev = &pdev->dev;
1048 
1049 	if (host->mode == USE_DMA_ACCESS)
1050 		init_completion(&host->dma_access_complete);
1051 
1052 	/* Link all private pointers */
1053 	mtd = nand_to_mtd(&host->nand);
1054 	nand_set_flash_node(nand, pdev->dev.of_node);
1055 
1056 	mtd->dev.parent = &pdev->dev;
1057 
1058 	/*
1059 	 * Setup default ECC mode. nand_dt_init() called from nand_scan_ident()
1060 	 * can overwrite this value if the DT provides a different value.
1061 	 */
1062 	nand->ecc.mode = NAND_ECC_HW;
1063 	nand->ecc.hwctl = fsmc_enable_hwecc;
1064 	nand->ecc.size = 512;
1065 	nand->badblockbits = 7;
1066 
1067 	if (host->mode == USE_DMA_ACCESS) {
1068 		dma_cap_zero(mask);
1069 		dma_cap_set(DMA_MEMCPY, mask);
1070 		host->read_dma_chan = dma_request_channel(mask, filter, NULL);
1071 		if (!host->read_dma_chan) {
1072 			dev_err(&pdev->dev, "Unable to get read dma channel\n");
1073 			goto disable_clk;
1074 		}
1075 		host->write_dma_chan = dma_request_channel(mask, filter, NULL);
1076 		if (!host->write_dma_chan) {
1077 			dev_err(&pdev->dev, "Unable to get write dma channel\n");
1078 			goto release_dma_read_chan;
1079 		}
1080 	}
1081 
1082 	if (host->dev_timings) {
1083 		fsmc_nand_setup(host, host->dev_timings);
1084 		nand->options |= NAND_KEEP_TIMINGS;
1085 	}
1086 
1087 	if (AMBA_REV_BITS(host->pid) >= 8) {
1088 		nand->ecc.read_page = fsmc_read_page_hwecc;
1089 		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
1090 		nand->ecc.correct = fsmc_bch8_correct_data;
1091 		nand->ecc.bytes = 13;
1092 		nand->ecc.strength = 8;
1093 	}
1094 
1095 	nand_controller_init(&host->base);
1096 	host->base.ops = &fsmc_nand_controller_ops;
1097 	nand->controller = &host->base;
1098 
1099 	/*
1100 	 * Scan to find existence of the device
1101 	 */
1102 	ret = nand_scan(nand, 1);
1103 	if (ret)
1104 		goto release_dma_write_chan;
1105 
1106 	mtd->name = "nand";
1107 	ret = mtd_device_register(mtd, NULL, 0);
1108 	if (ret)
1109 		goto cleanup_nand;
1110 
1111 	platform_set_drvdata(pdev, host);
1112 	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
1113 
1114 	return 0;
1115 
1116 cleanup_nand:
1117 	nand_cleanup(nand);
1118 release_dma_write_chan:
1119 	if (host->mode == USE_DMA_ACCESS)
1120 		dma_release_channel(host->write_dma_chan);
1121 release_dma_read_chan:
1122 	if (host->mode == USE_DMA_ACCESS)
1123 		dma_release_channel(host->read_dma_chan);
1124 disable_clk:
1125 	fsmc_nand_disable(host);
1126 	clk_disable_unprepare(host->clk);
1127 
1128 	return ret;
1129 }
1130 
1131 /*
1132  * Clean up routine
1133  */
1134 static int fsmc_nand_remove(struct platform_device *pdev)
1135 {
1136 	struct fsmc_nand_data *host = platform_get_drvdata(pdev);
1137 
1138 	if (host) {
1139 		struct nand_chip *chip = &host->nand;
1140 		int ret;
1141 
1142 		ret = mtd_device_unregister(nand_to_mtd(chip));
1143 		WARN_ON(ret);
1144 		nand_cleanup(chip);
1145 		fsmc_nand_disable(host);
1146 
1147 		if (host->mode == USE_DMA_ACCESS) {
1148 			dma_release_channel(host->write_dma_chan);
1149 			dma_release_channel(host->read_dma_chan);
1150 		}
1151 		clk_disable_unprepare(host->clk);
1152 	}
1153 
1154 	return 0;
1155 }
1156 
1157 #ifdef CONFIG_PM_SLEEP
1158 static int fsmc_nand_suspend(struct device *dev)
1159 {
1160 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1161 
1162 	if (host)
1163 		clk_disable_unprepare(host->clk);
1164 
1165 	return 0;
1166 }
1167 
1168 static int fsmc_nand_resume(struct device *dev)
1169 {
1170 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1171 
1172 	if (host) {
1173 		clk_prepare_enable(host->clk);
1174 		if (host->dev_timings)
1175 			fsmc_nand_setup(host, host->dev_timings);
1176 		nand_reset(&host->nand, 0);
1177 	}
1178 
1179 	return 0;
1180 }
1181 #endif
1182 
1183 static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
1184 
1185 static const struct of_device_id fsmc_nand_id_table[] = {
1186 	{ .compatible = "st,spear600-fsmc-nand" },
1187 	{ .compatible = "stericsson,fsmc-nand" },
1188 	{}
1189 };
1190 MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
1191 
1192 static struct platform_driver fsmc_nand_driver = {
1193 	.remove = fsmc_nand_remove,
1194 	.driver = {
1195 		.name = "fsmc-nand",
1196 		.of_match_table = fsmc_nand_id_table,
1197 		.pm = &fsmc_nand_pm_ops,
1198 	},
1199 };
1200 
1201 module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
1202 
1203 MODULE_LICENSE("GPL v2");
1204 MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
1205 MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");
1206