xref: /openbmc/linux/drivers/mtd/nand/raw/fsmc_nand.c (revision 63705da3)
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/nand-ecc-sw-hamming.h>
29 #include <linux/mtd/rawnand.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_interface(struct nand_chip *nand, int csline,
331 				const struct nand_interface_config *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 static int fsmc_correct_ecc1(struct nand_chip *chip,
437 			     unsigned char *buf,
438 			     unsigned char *read_ecc,
439 			     unsigned char *calc_ecc)
440 {
441 	bool sm_order = chip->ecc.options & NAND_ECC_SOFT_HAMMING_SM_ORDER;
442 
443 	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
444 				      chip->ecc.size, sm_order);
445 }
446 
447 /* Count the number of 0's in buff upto a max of max_bits */
448 static int count_written_bits(u8 *buff, int size, int max_bits)
449 {
450 	int k, written_bits = 0;
451 
452 	for (k = 0; k < size; k++) {
453 		written_bits += hweight8(~buff[k]);
454 		if (written_bits > max_bits)
455 			break;
456 	}
457 
458 	return written_bits;
459 }
460 
461 static void dma_complete(void *param)
462 {
463 	struct fsmc_nand_data *host = param;
464 
465 	complete(&host->dma_access_complete);
466 }
467 
468 static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
469 		    enum dma_data_direction direction)
470 {
471 	struct dma_chan *chan;
472 	struct dma_device *dma_dev;
473 	struct dma_async_tx_descriptor *tx;
474 	dma_addr_t dma_dst, dma_src, dma_addr;
475 	dma_cookie_t cookie;
476 	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
477 	int ret;
478 	unsigned long time_left;
479 
480 	if (direction == DMA_TO_DEVICE)
481 		chan = host->write_dma_chan;
482 	else if (direction == DMA_FROM_DEVICE)
483 		chan = host->read_dma_chan;
484 	else
485 		return -EINVAL;
486 
487 	dma_dev = chan->device;
488 	dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
489 
490 	if (direction == DMA_TO_DEVICE) {
491 		dma_src = dma_addr;
492 		dma_dst = host->data_pa;
493 	} else {
494 		dma_src = host->data_pa;
495 		dma_dst = dma_addr;
496 	}
497 
498 	tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
499 			len, flags);
500 	if (!tx) {
501 		dev_err(host->dev, "device_prep_dma_memcpy error\n");
502 		ret = -EIO;
503 		goto unmap_dma;
504 	}
505 
506 	tx->callback = dma_complete;
507 	tx->callback_param = host;
508 	cookie = tx->tx_submit(tx);
509 
510 	ret = dma_submit_error(cookie);
511 	if (ret) {
512 		dev_err(host->dev, "dma_submit_error %d\n", cookie);
513 		goto unmap_dma;
514 	}
515 
516 	dma_async_issue_pending(chan);
517 
518 	time_left =
519 	wait_for_completion_timeout(&host->dma_access_complete,
520 				    msecs_to_jiffies(3000));
521 	if (time_left == 0) {
522 		dmaengine_terminate_all(chan);
523 		dev_err(host->dev, "wait_for_completion_timeout\n");
524 		ret = -ETIMEDOUT;
525 		goto unmap_dma;
526 	}
527 
528 	ret = 0;
529 
530 unmap_dma:
531 	dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
532 
533 	return ret;
534 }
535 
536 /*
537  * fsmc_write_buf - write buffer to chip
538  * @host:	FSMC NAND controller
539  * @buf:	data buffer
540  * @len:	number of bytes to write
541  */
542 static void fsmc_write_buf(struct fsmc_nand_data *host, const u8 *buf,
543 			   int len)
544 {
545 	int i;
546 
547 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
548 	    IS_ALIGNED(len, sizeof(u32))) {
549 		u32 *p = (u32 *)buf;
550 
551 		len = len >> 2;
552 		for (i = 0; i < len; i++)
553 			writel_relaxed(p[i], host->data_va);
554 	} else {
555 		for (i = 0; i < len; i++)
556 			writeb_relaxed(buf[i], host->data_va);
557 	}
558 }
559 
560 /*
561  * fsmc_read_buf - read chip data into buffer
562  * @host:	FSMC NAND controller
563  * @buf:	buffer to store date
564  * @len:	number of bytes to read
565  */
566 static void fsmc_read_buf(struct fsmc_nand_data *host, u8 *buf, int len)
567 {
568 	int i;
569 
570 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
571 	    IS_ALIGNED(len, sizeof(u32))) {
572 		u32 *p = (u32 *)buf;
573 
574 		len = len >> 2;
575 		for (i = 0; i < len; i++)
576 			p[i] = readl_relaxed(host->data_va);
577 	} else {
578 		for (i = 0; i < len; i++)
579 			buf[i] = readb_relaxed(host->data_va);
580 	}
581 }
582 
583 /*
584  * fsmc_read_buf_dma - read chip data into buffer
585  * @host:	FSMC NAND controller
586  * @buf:	buffer to store date
587  * @len:	number of bytes to read
588  */
589 static void fsmc_read_buf_dma(struct fsmc_nand_data *host, u8 *buf,
590 			      int len)
591 {
592 	dma_xfer(host, buf, len, DMA_FROM_DEVICE);
593 }
594 
595 /*
596  * fsmc_write_buf_dma - write buffer to chip
597  * @host:	FSMC NAND controller
598  * @buf:	data buffer
599  * @len:	number of bytes to write
600  */
601 static void fsmc_write_buf_dma(struct fsmc_nand_data *host, const u8 *buf,
602 			       int len)
603 {
604 	dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
605 }
606 
607 /*
608  * fsmc_exec_op - hook called by the core to execute NAND operations
609  *
610  * This controller is simple enough and thus does not need to use the parser
611  * provided by the core, instead, handle every situation here.
612  */
613 static int fsmc_exec_op(struct nand_chip *chip, const struct nand_operation *op,
614 			bool check_only)
615 {
616 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
617 	const struct nand_op_instr *instr = NULL;
618 	int ret = 0;
619 	unsigned int op_id;
620 	int i;
621 
622 	if (check_only)
623 		return 0;
624 
625 	pr_debug("Executing operation [%d instructions]:\n", op->ninstrs);
626 
627 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
628 		instr = &op->instrs[op_id];
629 
630 		nand_op_trace("  ", instr);
631 
632 		switch (instr->type) {
633 		case NAND_OP_CMD_INSTR:
634 			writeb_relaxed(instr->ctx.cmd.opcode, host->cmd_va);
635 			break;
636 
637 		case NAND_OP_ADDR_INSTR:
638 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
639 				writeb_relaxed(instr->ctx.addr.addrs[i],
640 					       host->addr_va);
641 			break;
642 
643 		case NAND_OP_DATA_IN_INSTR:
644 			if (host->mode == USE_DMA_ACCESS)
645 				fsmc_read_buf_dma(host, instr->ctx.data.buf.in,
646 						  instr->ctx.data.len);
647 			else
648 				fsmc_read_buf(host, instr->ctx.data.buf.in,
649 					      instr->ctx.data.len);
650 			break;
651 
652 		case NAND_OP_DATA_OUT_INSTR:
653 			if (host->mode == USE_DMA_ACCESS)
654 				fsmc_write_buf_dma(host,
655 						   instr->ctx.data.buf.out,
656 						   instr->ctx.data.len);
657 			else
658 				fsmc_write_buf(host, instr->ctx.data.buf.out,
659 					       instr->ctx.data.len);
660 			break;
661 
662 		case NAND_OP_WAITRDY_INSTR:
663 			ret = nand_soft_waitrdy(chip,
664 						instr->ctx.waitrdy.timeout_ms);
665 			break;
666 		}
667 	}
668 
669 	return ret;
670 }
671 
672 /*
673  * fsmc_read_page_hwecc
674  * @chip:	nand chip info structure
675  * @buf:	buffer to store read data
676  * @oob_required:	caller expects OOB data read to chip->oob_poi
677  * @page:	page number to read
678  *
679  * This routine is needed for fsmc version 8 as reading from NAND chip has to be
680  * performed in a strict sequence as follows:
681  * data(512 byte) -> ecc(13 byte)
682  * After this read, fsmc hardware generates and reports error data bits(up to a
683  * max of 8 bits)
684  */
685 static int fsmc_read_page_hwecc(struct nand_chip *chip, u8 *buf,
686 				int oob_required, int page)
687 {
688 	struct mtd_info *mtd = nand_to_mtd(chip);
689 	int i, j, s, stat, eccsize = chip->ecc.size;
690 	int eccbytes = chip->ecc.bytes;
691 	int eccsteps = chip->ecc.steps;
692 	u8 *p = buf;
693 	u8 *ecc_calc = chip->ecc.calc_buf;
694 	u8 *ecc_code = chip->ecc.code_buf;
695 	int off, len, ret, group = 0;
696 	/*
697 	 * ecc_oob is intentionally taken as u16. In 16bit devices, we
698 	 * end up reading 14 bytes (7 words) from oob. The local array is
699 	 * to maintain word alignment
700 	 */
701 	u16 ecc_oob[7];
702 	u8 *oob = (u8 *)&ecc_oob[0];
703 	unsigned int max_bitflips = 0;
704 
705 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
706 		nand_read_page_op(chip, page, s * eccsize, NULL, 0);
707 		chip->ecc.hwctl(chip, NAND_ECC_READ);
708 		ret = nand_read_data_op(chip, p, eccsize, false, false);
709 		if (ret)
710 			return ret;
711 
712 		for (j = 0; j < eccbytes;) {
713 			struct mtd_oob_region oobregion;
714 
715 			ret = mtd_ooblayout_ecc(mtd, group++, &oobregion);
716 			if (ret)
717 				return ret;
718 
719 			off = oobregion.offset;
720 			len = oobregion.length;
721 
722 			/*
723 			 * length is intentionally kept a higher multiple of 2
724 			 * to read at least 13 bytes even in case of 16 bit NAND
725 			 * devices
726 			 */
727 			if (chip->options & NAND_BUSWIDTH_16)
728 				len = roundup(len, 2);
729 
730 			nand_read_oob_op(chip, page, off, oob + j, len);
731 			j += len;
732 		}
733 
734 		memcpy(&ecc_code[i], oob, chip->ecc.bytes);
735 		chip->ecc.calculate(chip, p, &ecc_calc[i]);
736 
737 		stat = chip->ecc.correct(chip, p, &ecc_code[i], &ecc_calc[i]);
738 		if (stat < 0) {
739 			mtd->ecc_stats.failed++;
740 		} else {
741 			mtd->ecc_stats.corrected += stat;
742 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
743 		}
744 	}
745 
746 	return max_bitflips;
747 }
748 
749 /*
750  * fsmc_bch8_correct_data
751  * @mtd:	mtd info structure
752  * @dat:	buffer of read data
753  * @read_ecc:	ecc read from device spare area
754  * @calc_ecc:	ecc calculated from read data
755  *
756  * calc_ecc is a 104 bit information containing maximum of 8 error
757  * offset information of 13 bits each in 512 bytes of read data.
758  */
759 static int fsmc_bch8_correct_data(struct nand_chip *chip, u8 *dat,
760 				  u8 *read_ecc, u8 *calc_ecc)
761 {
762 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
763 	u32 err_idx[8];
764 	u32 num_err, i;
765 	u32 ecc1, ecc2, ecc3, ecc4;
766 
767 	num_err = (readl_relaxed(host->regs_va + STS) >> 10) & 0xF;
768 
769 	/* no bit flipping */
770 	if (likely(num_err == 0))
771 		return 0;
772 
773 	/* too many errors */
774 	if (unlikely(num_err > 8)) {
775 		/*
776 		 * This is a temporary erase check. A newly erased page read
777 		 * would result in an ecc error because the oob data is also
778 		 * erased to FF and the calculated ecc for an FF data is not
779 		 * FF..FF.
780 		 * This is a workaround to skip performing correction in case
781 		 * data is FF..FF
782 		 *
783 		 * Logic:
784 		 * For every page, each bit written as 0 is counted until these
785 		 * number of bits are greater than 8 (the maximum correction
786 		 * capability of FSMC for each 512 + 13 bytes)
787 		 */
788 
789 		int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
790 		int bits_data = count_written_bits(dat, chip->ecc.size, 8);
791 
792 		if ((bits_ecc + bits_data) <= 8) {
793 			if (bits_data)
794 				memset(dat, 0xff, chip->ecc.size);
795 			return bits_data;
796 		}
797 
798 		return -EBADMSG;
799 	}
800 
801 	/*
802 	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
803 	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
804 	 *
805 	 * calc_ecc is a 104 bit information containing maximum of 8 error
806 	 * offset information of 13 bits each. calc_ecc is copied into a
807 	 * u64 array and error offset indexes are populated in err_idx
808 	 * array
809 	 */
810 	ecc1 = readl_relaxed(host->regs_va + ECC1);
811 	ecc2 = readl_relaxed(host->regs_va + ECC2);
812 	ecc3 = readl_relaxed(host->regs_va + ECC3);
813 	ecc4 = readl_relaxed(host->regs_va + STS);
814 
815 	err_idx[0] = (ecc1 >> 0) & 0x1FFF;
816 	err_idx[1] = (ecc1 >> 13) & 0x1FFF;
817 	err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
818 	err_idx[3] = (ecc2 >> 7) & 0x1FFF;
819 	err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
820 	err_idx[5] = (ecc3 >> 1) & 0x1FFF;
821 	err_idx[6] = (ecc3 >> 14) & 0x1FFF;
822 	err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
823 
824 	i = 0;
825 	while (num_err--) {
826 		err_idx[i] ^= 3;
827 
828 		if (err_idx[i] < chip->ecc.size * 8) {
829 			int err = err_idx[i];
830 
831 			dat[err >> 3] ^= BIT(err & 7);
832 			i++;
833 		}
834 	}
835 	return i;
836 }
837 
838 static bool filter(struct dma_chan *chan, void *slave)
839 {
840 	chan->private = slave;
841 	return true;
842 }
843 
844 static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
845 				     struct fsmc_nand_data *host,
846 				     struct nand_chip *nand)
847 {
848 	struct device_node *np = pdev->dev.of_node;
849 	u32 val;
850 	int ret;
851 
852 	nand->options = 0;
853 
854 	if (!of_property_read_u32(np, "bank-width", &val)) {
855 		if (val == 2) {
856 			nand->options |= NAND_BUSWIDTH_16;
857 		} else if (val != 1) {
858 			dev_err(&pdev->dev, "invalid bank-width %u\n", val);
859 			return -EINVAL;
860 		}
861 	}
862 
863 	if (of_get_property(np, "nand-skip-bbtscan", NULL))
864 		nand->options |= NAND_SKIP_BBTSCAN;
865 
866 	host->dev_timings = devm_kzalloc(&pdev->dev,
867 					 sizeof(*host->dev_timings),
868 					 GFP_KERNEL);
869 	if (!host->dev_timings)
870 		return -ENOMEM;
871 
872 	ret = of_property_read_u8_array(np, "timings", (u8 *)host->dev_timings,
873 					sizeof(*host->dev_timings));
874 	if (ret)
875 		host->dev_timings = NULL;
876 
877 	/* Set default NAND bank to 0 */
878 	host->bank = 0;
879 	if (!of_property_read_u32(np, "bank", &val)) {
880 		if (val > 3) {
881 			dev_err(&pdev->dev, "invalid bank %u\n", val);
882 			return -EINVAL;
883 		}
884 		host->bank = val;
885 	}
886 	return 0;
887 }
888 
889 static int fsmc_nand_attach_chip(struct nand_chip *nand)
890 {
891 	struct mtd_info *mtd = nand_to_mtd(nand);
892 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
893 
894 	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_INVALID)
895 		nand->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
896 
897 	if (!nand->ecc.size)
898 		nand->ecc.size = 512;
899 
900 	if (AMBA_REV_BITS(host->pid) >= 8) {
901 		nand->ecc.read_page = fsmc_read_page_hwecc;
902 		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
903 		nand->ecc.correct = fsmc_bch8_correct_data;
904 		nand->ecc.bytes = 13;
905 		nand->ecc.strength = 8;
906 	}
907 
908 	if (AMBA_REV_BITS(host->pid) >= 8) {
909 		switch (mtd->oobsize) {
910 		case 16:
911 		case 64:
912 		case 128:
913 		case 224:
914 		case 256:
915 			break;
916 		default:
917 			dev_warn(host->dev,
918 				 "No oob scheme defined for oobsize %d\n",
919 				 mtd->oobsize);
920 			return -EINVAL;
921 		}
922 
923 		mtd_set_ooblayout(mtd, &fsmc_ecc4_ooblayout_ops);
924 
925 		return 0;
926 	}
927 
928 	switch (nand->ecc.engine_type) {
929 	case NAND_ECC_ENGINE_TYPE_ON_HOST:
930 		dev_info(host->dev, "Using 1-bit HW ECC scheme\n");
931 		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
932 		nand->ecc.correct = fsmc_correct_ecc1;
933 		nand->ecc.hwctl = fsmc_enable_hwecc;
934 		nand->ecc.bytes = 3;
935 		nand->ecc.strength = 1;
936 		nand->ecc.options |= NAND_ECC_SOFT_HAMMING_SM_ORDER;
937 		break;
938 
939 	case NAND_ECC_ENGINE_TYPE_SOFT:
940 		if (nand->ecc.algo == NAND_ECC_ALGO_BCH) {
941 			dev_info(host->dev,
942 				 "Using 4-bit SW BCH ECC scheme\n");
943 			break;
944 		}
945 		break;
946 
947 	case NAND_ECC_ENGINE_TYPE_ON_DIE:
948 		break;
949 
950 	default:
951 		dev_err(host->dev, "Unsupported ECC mode!\n");
952 		return -ENOTSUPP;
953 	}
954 
955 	/*
956 	 * Don't set layout for BCH4 SW ECC. This will be
957 	 * generated later during BCH initialization.
958 	 */
959 	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST) {
960 		switch (mtd->oobsize) {
961 		case 16:
962 		case 64:
963 		case 128:
964 			mtd_set_ooblayout(mtd,
965 					  &fsmc_ecc1_ooblayout_ops);
966 			break;
967 		default:
968 			dev_warn(host->dev,
969 				 "No oob scheme defined for oobsize %d\n",
970 				 mtd->oobsize);
971 			return -EINVAL;
972 		}
973 	}
974 
975 	return 0;
976 }
977 
978 static const struct nand_controller_ops fsmc_nand_controller_ops = {
979 	.attach_chip = fsmc_nand_attach_chip,
980 	.exec_op = fsmc_exec_op,
981 	.setup_interface = fsmc_setup_interface,
982 };
983 
984 /**
985  * fsmc_nand_disable() - Disables the NAND bank
986  * @host: The instance to disable
987  */
988 static void fsmc_nand_disable(struct fsmc_nand_data *host)
989 {
990 	u32 val;
991 
992 	val = readl(host->regs_va + FSMC_PC);
993 	val &= ~FSMC_ENABLE;
994 	writel(val, host->regs_va + FSMC_PC);
995 }
996 
997 /*
998  * fsmc_nand_probe - Probe function
999  * @pdev:       platform device structure
1000  */
1001 static int __init fsmc_nand_probe(struct platform_device *pdev)
1002 {
1003 	struct fsmc_nand_data *host;
1004 	struct mtd_info *mtd;
1005 	struct nand_chip *nand;
1006 	struct resource *res;
1007 	void __iomem *base;
1008 	dma_cap_mask_t mask;
1009 	int ret = 0;
1010 	u32 pid;
1011 	int i;
1012 
1013 	/* Allocate memory for the device structure (and zero it) */
1014 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
1015 	if (!host)
1016 		return -ENOMEM;
1017 
1018 	nand = &host->nand;
1019 
1020 	ret = fsmc_nand_probe_config_dt(pdev, host, nand);
1021 	if (ret)
1022 		return ret;
1023 
1024 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
1025 	host->data_va = devm_ioremap_resource(&pdev->dev, res);
1026 	if (IS_ERR(host->data_va))
1027 		return PTR_ERR(host->data_va);
1028 
1029 	host->data_pa = (dma_addr_t)res->start;
1030 
1031 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
1032 	host->addr_va = devm_ioremap_resource(&pdev->dev, res);
1033 	if (IS_ERR(host->addr_va))
1034 		return PTR_ERR(host->addr_va);
1035 
1036 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
1037 	host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
1038 	if (IS_ERR(host->cmd_va))
1039 		return PTR_ERR(host->cmd_va);
1040 
1041 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
1042 	base = devm_ioremap_resource(&pdev->dev, res);
1043 	if (IS_ERR(base))
1044 		return PTR_ERR(base);
1045 
1046 	host->regs_va = base + FSMC_NOR_REG_SIZE +
1047 		(host->bank * FSMC_NAND_BANK_SZ);
1048 
1049 	host->clk = devm_clk_get(&pdev->dev, NULL);
1050 	if (IS_ERR(host->clk)) {
1051 		dev_err(&pdev->dev, "failed to fetch block clock\n");
1052 		return PTR_ERR(host->clk);
1053 	}
1054 
1055 	ret = clk_prepare_enable(host->clk);
1056 	if (ret)
1057 		return ret;
1058 
1059 	/*
1060 	 * This device ID is actually a common AMBA ID as used on the
1061 	 * AMBA PrimeCell bus. However it is not a PrimeCell.
1062 	 */
1063 	for (pid = 0, i = 0; i < 4; i++)
1064 		pid |= (readl(base + resource_size(res) - 0x20 + 4 * i) &
1065 			255) << (i * 8);
1066 
1067 	host->pid = pid;
1068 
1069 	dev_info(&pdev->dev,
1070 		 "FSMC device partno %03x, manufacturer %02x, revision %02x, config %02x\n",
1071 		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
1072 		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
1073 
1074 	host->dev = &pdev->dev;
1075 
1076 	if (host->mode == USE_DMA_ACCESS)
1077 		init_completion(&host->dma_access_complete);
1078 
1079 	/* Link all private pointers */
1080 	mtd = nand_to_mtd(&host->nand);
1081 	nand_set_flash_node(nand, pdev->dev.of_node);
1082 
1083 	mtd->dev.parent = &pdev->dev;
1084 
1085 	nand->badblockbits = 7;
1086 
1087 	if (host->mode == USE_DMA_ACCESS) {
1088 		dma_cap_zero(mask);
1089 		dma_cap_set(DMA_MEMCPY, mask);
1090 		host->read_dma_chan = dma_request_channel(mask, filter, NULL);
1091 		if (!host->read_dma_chan) {
1092 			dev_err(&pdev->dev, "Unable to get read dma channel\n");
1093 			ret = -ENODEV;
1094 			goto disable_clk;
1095 		}
1096 		host->write_dma_chan = dma_request_channel(mask, filter, NULL);
1097 		if (!host->write_dma_chan) {
1098 			dev_err(&pdev->dev, "Unable to get write dma channel\n");
1099 			ret = -ENODEV;
1100 			goto release_dma_read_chan;
1101 		}
1102 	}
1103 
1104 	if (host->dev_timings) {
1105 		fsmc_nand_setup(host, host->dev_timings);
1106 		nand->options |= NAND_KEEP_TIMINGS;
1107 	}
1108 
1109 	nand_controller_init(&host->base);
1110 	host->base.ops = &fsmc_nand_controller_ops;
1111 	nand->controller = &host->base;
1112 
1113 	/*
1114 	 * Scan to find existence of the device
1115 	 */
1116 	ret = nand_scan(nand, 1);
1117 	if (ret)
1118 		goto release_dma_write_chan;
1119 
1120 	mtd->name = "nand";
1121 	ret = mtd_device_register(mtd, NULL, 0);
1122 	if (ret)
1123 		goto cleanup_nand;
1124 
1125 	platform_set_drvdata(pdev, host);
1126 	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
1127 
1128 	return 0;
1129 
1130 cleanup_nand:
1131 	nand_cleanup(nand);
1132 release_dma_write_chan:
1133 	if (host->mode == USE_DMA_ACCESS)
1134 		dma_release_channel(host->write_dma_chan);
1135 release_dma_read_chan:
1136 	if (host->mode == USE_DMA_ACCESS)
1137 		dma_release_channel(host->read_dma_chan);
1138 disable_clk:
1139 	fsmc_nand_disable(host);
1140 	clk_disable_unprepare(host->clk);
1141 
1142 	return ret;
1143 }
1144 
1145 /*
1146  * Clean up routine
1147  */
1148 static int fsmc_nand_remove(struct platform_device *pdev)
1149 {
1150 	struct fsmc_nand_data *host = platform_get_drvdata(pdev);
1151 
1152 	if (host) {
1153 		struct nand_chip *chip = &host->nand;
1154 		int ret;
1155 
1156 		ret = mtd_device_unregister(nand_to_mtd(chip));
1157 		WARN_ON(ret);
1158 		nand_cleanup(chip);
1159 		fsmc_nand_disable(host);
1160 
1161 		if (host->mode == USE_DMA_ACCESS) {
1162 			dma_release_channel(host->write_dma_chan);
1163 			dma_release_channel(host->read_dma_chan);
1164 		}
1165 		clk_disable_unprepare(host->clk);
1166 	}
1167 
1168 	return 0;
1169 }
1170 
1171 #ifdef CONFIG_PM_SLEEP
1172 static int fsmc_nand_suspend(struct device *dev)
1173 {
1174 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1175 
1176 	if (host)
1177 		clk_disable_unprepare(host->clk);
1178 
1179 	return 0;
1180 }
1181 
1182 static int fsmc_nand_resume(struct device *dev)
1183 {
1184 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1185 
1186 	if (host) {
1187 		clk_prepare_enable(host->clk);
1188 		if (host->dev_timings)
1189 			fsmc_nand_setup(host, host->dev_timings);
1190 		nand_reset(&host->nand, 0);
1191 	}
1192 
1193 	return 0;
1194 }
1195 #endif
1196 
1197 static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
1198 
1199 static const struct of_device_id fsmc_nand_id_table[] = {
1200 	{ .compatible = "st,spear600-fsmc-nand" },
1201 	{ .compatible = "stericsson,fsmc-nand" },
1202 	{}
1203 };
1204 MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
1205 
1206 static struct platform_driver fsmc_nand_driver = {
1207 	.remove = fsmc_nand_remove,
1208 	.driver = {
1209 		.name = "fsmc-nand",
1210 		.of_match_table = fsmc_nand_id_table,
1211 		.pm = &fsmc_nand_pm_ops,
1212 	},
1213 };
1214 
1215 module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
1216 
1217 MODULE_LICENSE("GPL v2");
1218 MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
1219 MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");
1220