xref: /openbmc/linux/drivers/mtd/nand/raw/fsmc_nand.c (revision 28dce2c4)
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/platform_device.h>
30 #include <linux/of.h>
31 #include <linux/mtd/partitions.h>
32 #include <linux/io.h>
33 #include <linux/slab.h>
34 #include <linux/amba/bus.h>
35 #include <mtd/mtd-abi.h>
36 
37 /* fsmc controller registers for NOR flash */
38 #define CTRL			0x0
39 	/* ctrl register definitions */
40 	#define BANK_ENABLE		BIT(0)
41 	#define MUXED			BIT(1)
42 	#define NOR_DEV			(2 << 2)
43 	#define WIDTH_16		BIT(4)
44 	#define RSTPWRDWN		BIT(6)
45 	#define WPROT			BIT(7)
46 	#define WRT_ENABLE		BIT(12)
47 	#define WAIT_ENB		BIT(13)
48 
49 #define CTRL_TIM		0x4
50 	/* ctrl_tim register definitions */
51 
52 #define FSMC_NOR_BANK_SZ	0x8
53 #define FSMC_NOR_REG_SIZE	0x40
54 
55 #define FSMC_NOR_REG(base, bank, reg)	((base) +			\
56 					 (FSMC_NOR_BANK_SZ * (bank)) +	\
57 					 (reg))
58 
59 /* fsmc controller registers for NAND flash */
60 #define FSMC_PC			0x00
61 	/* pc register definitions */
62 	#define FSMC_RESET		BIT(0)
63 	#define FSMC_WAITON		BIT(1)
64 	#define FSMC_ENABLE		BIT(2)
65 	#define FSMC_DEVTYPE_NAND	BIT(3)
66 	#define FSMC_DEVWID_16		BIT(4)
67 	#define FSMC_ECCEN		BIT(6)
68 	#define FSMC_ECCPLEN_256	BIT(7)
69 	#define FSMC_TCLR_SHIFT		(9)
70 	#define FSMC_TCLR_MASK		(0xF)
71 	#define FSMC_TAR_SHIFT		(13)
72 	#define FSMC_TAR_MASK		(0xF)
73 #define STS			0x04
74 	/* sts register definitions */
75 	#define FSMC_CODE_RDY		BIT(15)
76 #define COMM			0x08
77 	/* comm register definitions */
78 	#define FSMC_TSET_SHIFT		0
79 	#define FSMC_TSET_MASK		0xFF
80 	#define FSMC_TWAIT_SHIFT	8
81 	#define FSMC_TWAIT_MASK		0xFF
82 	#define FSMC_THOLD_SHIFT	16
83 	#define FSMC_THOLD_MASK		0xFF
84 	#define FSMC_THIZ_SHIFT		24
85 	#define FSMC_THIZ_MASK		0xFF
86 #define ATTRIB			0x0C
87 #define IOATA			0x10
88 #define ECC1			0x14
89 #define ECC2			0x18
90 #define ECC3			0x1C
91 #define FSMC_NAND_BANK_SZ	0x20
92 
93 #define FSMC_BUSY_WAIT_TIMEOUT	(1 * HZ)
94 
95 struct fsmc_nand_timings {
96 	u8 tclr;
97 	u8 tar;
98 	u8 thiz;
99 	u8 thold;
100 	u8 twait;
101 	u8 tset;
102 };
103 
104 enum access_mode {
105 	USE_DMA_ACCESS = 1,
106 	USE_WORD_ACCESS,
107 };
108 
109 /**
110  * struct fsmc_nand_data - structure for FSMC NAND device state
111  *
112  * @base:		Inherit from the nand_controller struct
113  * @pid:		Part ID on the AMBA PrimeCell format
114  * @nand:		Chip related info for a NAND flash.
115  *
116  * @bank:		Bank number for probed device.
117  * @dev:		Parent device
118  * @mode:		Access mode
119  * @clk:		Clock structure for FSMC.
120  *
121  * @read_dma_chan:	DMA channel for read access
122  * @write_dma_chan:	DMA channel for write access to NAND
123  * @dma_access_complete: Completion structure
124  *
125  * @dev_timings:	NAND timings
126  *
127  * @data_pa:		NAND Physical port for Data.
128  * @data_va:		NAND port for Data.
129  * @cmd_va:		NAND port for Command.
130  * @addr_va:		NAND port for Address.
131  * @regs_va:		Registers base address for a given bank.
132  */
133 struct fsmc_nand_data {
134 	struct nand_controller	base;
135 	u32			pid;
136 	struct nand_chip	nand;
137 
138 	unsigned int		bank;
139 	struct device		*dev;
140 	enum access_mode	mode;
141 	struct clk		*clk;
142 
143 	/* DMA related objects */
144 	struct dma_chan		*read_dma_chan;
145 	struct dma_chan		*write_dma_chan;
146 	struct completion	dma_access_complete;
147 
148 	struct fsmc_nand_timings *dev_timings;
149 
150 	dma_addr_t		data_pa;
151 	void __iomem		*data_va;
152 	void __iomem		*cmd_va;
153 	void __iomem		*addr_va;
154 	void __iomem		*regs_va;
155 };
156 
157 static int fsmc_ecc1_ooblayout_ecc(struct mtd_info *mtd, int section,
158 				   struct mtd_oob_region *oobregion)
159 {
160 	struct nand_chip *chip = mtd_to_nand(mtd);
161 
162 	if (section >= chip->ecc.steps)
163 		return -ERANGE;
164 
165 	oobregion->offset = (section * 16) + 2;
166 	oobregion->length = 3;
167 
168 	return 0;
169 }
170 
171 static int fsmc_ecc1_ooblayout_free(struct mtd_info *mtd, int section,
172 				    struct mtd_oob_region *oobregion)
173 {
174 	struct nand_chip *chip = mtd_to_nand(mtd);
175 
176 	if (section >= chip->ecc.steps)
177 		return -ERANGE;
178 
179 	oobregion->offset = (section * 16) + 8;
180 
181 	if (section < chip->ecc.steps - 1)
182 		oobregion->length = 8;
183 	else
184 		oobregion->length = mtd->oobsize - oobregion->offset;
185 
186 	return 0;
187 }
188 
189 static const struct mtd_ooblayout_ops fsmc_ecc1_ooblayout_ops = {
190 	.ecc = fsmc_ecc1_ooblayout_ecc,
191 	.free = fsmc_ecc1_ooblayout_free,
192 };
193 
194 /*
195  * ECC placement definitions in oobfree type format.
196  * There are 13 bytes of ecc for every 512 byte block and it has to be read
197  * consecutively and immediately after the 512 byte data block for hardware to
198  * generate the error bit offsets in 512 byte data.
199  */
200 static int fsmc_ecc4_ooblayout_ecc(struct mtd_info *mtd, int section,
201 				   struct mtd_oob_region *oobregion)
202 {
203 	struct nand_chip *chip = mtd_to_nand(mtd);
204 
205 	if (section >= chip->ecc.steps)
206 		return -ERANGE;
207 
208 	oobregion->length = chip->ecc.bytes;
209 
210 	if (!section && mtd->writesize <= 512)
211 		oobregion->offset = 0;
212 	else
213 		oobregion->offset = (section * 16) + 2;
214 
215 	return 0;
216 }
217 
218 static int fsmc_ecc4_ooblayout_free(struct mtd_info *mtd, int section,
219 				    struct mtd_oob_region *oobregion)
220 {
221 	struct nand_chip *chip = mtd_to_nand(mtd);
222 
223 	if (section >= chip->ecc.steps)
224 		return -ERANGE;
225 
226 	oobregion->offset = (section * 16) + 15;
227 
228 	if (section < chip->ecc.steps - 1)
229 		oobregion->length = 3;
230 	else
231 		oobregion->length = mtd->oobsize - oobregion->offset;
232 
233 	return 0;
234 }
235 
236 static const struct mtd_ooblayout_ops fsmc_ecc4_ooblayout_ops = {
237 	.ecc = fsmc_ecc4_ooblayout_ecc,
238 	.free = fsmc_ecc4_ooblayout_free,
239 };
240 
241 static inline struct fsmc_nand_data *nand_to_fsmc(struct nand_chip *chip)
242 {
243 	return container_of(chip, struct fsmc_nand_data, nand);
244 }
245 
246 /*
247  * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
248  *
249  * This routine initializes timing parameters related to NAND memory access in
250  * FSMC registers
251  */
252 static void fsmc_nand_setup(struct fsmc_nand_data *host,
253 			    struct fsmc_nand_timings *tims)
254 {
255 	u32 value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
256 	u32 tclr, tar, thiz, thold, twait, tset;
257 
258 	tclr = (tims->tclr & FSMC_TCLR_MASK) << FSMC_TCLR_SHIFT;
259 	tar = (tims->tar & FSMC_TAR_MASK) << FSMC_TAR_SHIFT;
260 	thiz = (tims->thiz & FSMC_THIZ_MASK) << FSMC_THIZ_SHIFT;
261 	thold = (tims->thold & FSMC_THOLD_MASK) << FSMC_THOLD_SHIFT;
262 	twait = (tims->twait & FSMC_TWAIT_MASK) << FSMC_TWAIT_SHIFT;
263 	tset = (tims->tset & FSMC_TSET_MASK) << FSMC_TSET_SHIFT;
264 
265 	if (host->nand.options & NAND_BUSWIDTH_16)
266 		value |= FSMC_DEVWID_16;
267 
268 	writel_relaxed(value | tclr | tar, host->regs_va + FSMC_PC);
269 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + COMM);
270 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + ATTRIB);
271 }
272 
273 static int fsmc_calc_timings(struct fsmc_nand_data *host,
274 			     const struct nand_sdr_timings *sdrt,
275 			     struct fsmc_nand_timings *tims)
276 {
277 	unsigned long hclk = clk_get_rate(host->clk);
278 	unsigned long hclkn = NSEC_PER_SEC / hclk;
279 	u32 thiz, thold, twait, tset;
280 
281 	if (sdrt->tRC_min < 30000)
282 		return -EOPNOTSUPP;
283 
284 	tims->tar = DIV_ROUND_UP(sdrt->tAR_min / 1000, hclkn) - 1;
285 	if (tims->tar > FSMC_TAR_MASK)
286 		tims->tar = FSMC_TAR_MASK;
287 	tims->tclr = DIV_ROUND_UP(sdrt->tCLR_min / 1000, hclkn) - 1;
288 	if (tims->tclr > FSMC_TCLR_MASK)
289 		tims->tclr = FSMC_TCLR_MASK;
290 
291 	thiz = sdrt->tCS_min - sdrt->tWP_min;
292 	tims->thiz = DIV_ROUND_UP(thiz / 1000, hclkn);
293 
294 	thold = sdrt->tDH_min;
295 	if (thold < sdrt->tCH_min)
296 		thold = sdrt->tCH_min;
297 	if (thold < sdrt->tCLH_min)
298 		thold = sdrt->tCLH_min;
299 	if (thold < sdrt->tWH_min)
300 		thold = sdrt->tWH_min;
301 	if (thold < sdrt->tALH_min)
302 		thold = sdrt->tALH_min;
303 	if (thold < sdrt->tREH_min)
304 		thold = sdrt->tREH_min;
305 	tims->thold = DIV_ROUND_UP(thold / 1000, hclkn);
306 	if (tims->thold == 0)
307 		tims->thold = 1;
308 	else if (tims->thold > FSMC_THOLD_MASK)
309 		tims->thold = FSMC_THOLD_MASK;
310 
311 	twait = max(sdrt->tRP_min, sdrt->tWP_min);
312 	tims->twait = DIV_ROUND_UP(twait / 1000, hclkn) - 1;
313 	if (tims->twait == 0)
314 		tims->twait = 1;
315 	else if (tims->twait > FSMC_TWAIT_MASK)
316 		tims->twait = FSMC_TWAIT_MASK;
317 
318 	tset = max(sdrt->tCS_min - sdrt->tWP_min,
319 		   sdrt->tCEA_max - sdrt->tREA_max);
320 	tims->tset = DIV_ROUND_UP(tset / 1000, hclkn) - 1;
321 	if (tims->tset == 0)
322 		tims->tset = 1;
323 	else if (tims->tset > FSMC_TSET_MASK)
324 		tims->tset = FSMC_TSET_MASK;
325 
326 	return 0;
327 }
328 
329 static int fsmc_setup_interface(struct nand_chip *nand, int csline,
330 				const struct nand_interface_config *conf)
331 {
332 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
333 	struct fsmc_nand_timings tims;
334 	const struct nand_sdr_timings *sdrt;
335 	int ret;
336 
337 	sdrt = nand_get_sdr_timings(conf);
338 	if (IS_ERR(sdrt))
339 		return PTR_ERR(sdrt);
340 
341 	ret = fsmc_calc_timings(host, sdrt, &tims);
342 	if (ret)
343 		return ret;
344 
345 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
346 		return 0;
347 
348 	fsmc_nand_setup(host, &tims);
349 
350 	return 0;
351 }
352 
353 /*
354  * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
355  */
356 static void fsmc_enable_hwecc(struct nand_chip *chip, int mode)
357 {
358 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
359 
360 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCPLEN_256,
361 		       host->regs_va + FSMC_PC);
362 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCEN,
363 		       host->regs_va + FSMC_PC);
364 	writel_relaxed(readl(host->regs_va + FSMC_PC) | FSMC_ECCEN,
365 		       host->regs_va + FSMC_PC);
366 }
367 
368 /*
369  * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
370  * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
371  * max of 8-bits)
372  */
373 static int fsmc_read_hwecc_ecc4(struct nand_chip *chip, const u8 *data,
374 				u8 *ecc)
375 {
376 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
377 	u32 ecc_tmp;
378 	unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;
379 
380 	do {
381 		if (readl_relaxed(host->regs_va + STS) & FSMC_CODE_RDY)
382 			break;
383 
384 		cond_resched();
385 	} while (!time_after_eq(jiffies, deadline));
386 
387 	if (time_after_eq(jiffies, deadline)) {
388 		dev_err(host->dev, "calculate ecc timed out\n");
389 		return -ETIMEDOUT;
390 	}
391 
392 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
393 	ecc[0] = ecc_tmp;
394 	ecc[1] = ecc_tmp >> 8;
395 	ecc[2] = ecc_tmp >> 16;
396 	ecc[3] = ecc_tmp >> 24;
397 
398 	ecc_tmp = readl_relaxed(host->regs_va + ECC2);
399 	ecc[4] = ecc_tmp;
400 	ecc[5] = ecc_tmp >> 8;
401 	ecc[6] = ecc_tmp >> 16;
402 	ecc[7] = ecc_tmp >> 24;
403 
404 	ecc_tmp = readl_relaxed(host->regs_va + ECC3);
405 	ecc[8] = ecc_tmp;
406 	ecc[9] = ecc_tmp >> 8;
407 	ecc[10] = ecc_tmp >> 16;
408 	ecc[11] = ecc_tmp >> 24;
409 
410 	ecc_tmp = readl_relaxed(host->regs_va + STS);
411 	ecc[12] = ecc_tmp >> 16;
412 
413 	return 0;
414 }
415 
416 /*
417  * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
418  * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
419  * max of 1-bit)
420  */
421 static int fsmc_read_hwecc_ecc1(struct nand_chip *chip, const u8 *data,
422 				u8 *ecc)
423 {
424 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
425 	u32 ecc_tmp;
426 
427 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
428 	ecc[0] = ecc_tmp;
429 	ecc[1] = ecc_tmp >> 8;
430 	ecc[2] = ecc_tmp >> 16;
431 
432 	return 0;
433 }
434 
435 /* Count the number of 0's in buff upto a max of max_bits */
436 static int count_written_bits(u8 *buff, int size, int max_bits)
437 {
438 	int k, written_bits = 0;
439 
440 	for (k = 0; k < size; k++) {
441 		written_bits += hweight8(~buff[k]);
442 		if (written_bits > max_bits)
443 			break;
444 	}
445 
446 	return written_bits;
447 }
448 
449 static void dma_complete(void *param)
450 {
451 	struct fsmc_nand_data *host = param;
452 
453 	complete(&host->dma_access_complete);
454 }
455 
456 static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
457 		    enum dma_data_direction direction)
458 {
459 	struct dma_chan *chan;
460 	struct dma_device *dma_dev;
461 	struct dma_async_tx_descriptor *tx;
462 	dma_addr_t dma_dst, dma_src, dma_addr;
463 	dma_cookie_t cookie;
464 	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
465 	int ret;
466 	unsigned long time_left;
467 
468 	if (direction == DMA_TO_DEVICE)
469 		chan = host->write_dma_chan;
470 	else if (direction == DMA_FROM_DEVICE)
471 		chan = host->read_dma_chan;
472 	else
473 		return -EINVAL;
474 
475 	dma_dev = chan->device;
476 	dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
477 
478 	if (direction == DMA_TO_DEVICE) {
479 		dma_src = dma_addr;
480 		dma_dst = host->data_pa;
481 	} else {
482 		dma_src = host->data_pa;
483 		dma_dst = dma_addr;
484 	}
485 
486 	tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
487 			len, flags);
488 	if (!tx) {
489 		dev_err(host->dev, "device_prep_dma_memcpy error\n");
490 		ret = -EIO;
491 		goto unmap_dma;
492 	}
493 
494 	tx->callback = dma_complete;
495 	tx->callback_param = host;
496 	cookie = tx->tx_submit(tx);
497 
498 	ret = dma_submit_error(cookie);
499 	if (ret) {
500 		dev_err(host->dev, "dma_submit_error %d\n", cookie);
501 		goto unmap_dma;
502 	}
503 
504 	dma_async_issue_pending(chan);
505 
506 	time_left =
507 	wait_for_completion_timeout(&host->dma_access_complete,
508 				    msecs_to_jiffies(3000));
509 	if (time_left == 0) {
510 		dmaengine_terminate_all(chan);
511 		dev_err(host->dev, "wait_for_completion_timeout\n");
512 		ret = -ETIMEDOUT;
513 		goto unmap_dma;
514 	}
515 
516 	ret = 0;
517 
518 unmap_dma:
519 	dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
520 
521 	return ret;
522 }
523 
524 /*
525  * fsmc_write_buf - write buffer to chip
526  * @host:	FSMC NAND controller
527  * @buf:	data buffer
528  * @len:	number of bytes to write
529  */
530 static void fsmc_write_buf(struct fsmc_nand_data *host, const u8 *buf,
531 			   int len)
532 {
533 	int i;
534 
535 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
536 	    IS_ALIGNED(len, sizeof(u32))) {
537 		u32 *p = (u32 *)buf;
538 
539 		len = len >> 2;
540 		for (i = 0; i < len; i++)
541 			writel_relaxed(p[i], host->data_va);
542 	} else {
543 		for (i = 0; i < len; i++)
544 			writeb_relaxed(buf[i], host->data_va);
545 	}
546 }
547 
548 /*
549  * fsmc_read_buf - read chip data into buffer
550  * @host:	FSMC NAND controller
551  * @buf:	buffer to store date
552  * @len:	number of bytes to read
553  */
554 static void fsmc_read_buf(struct fsmc_nand_data *host, u8 *buf, int len)
555 {
556 	int i;
557 
558 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
559 	    IS_ALIGNED(len, sizeof(u32))) {
560 		u32 *p = (u32 *)buf;
561 
562 		len = len >> 2;
563 		for (i = 0; i < len; i++)
564 			p[i] = readl_relaxed(host->data_va);
565 	} else {
566 		for (i = 0; i < len; i++)
567 			buf[i] = readb_relaxed(host->data_va);
568 	}
569 }
570 
571 /*
572  * fsmc_read_buf_dma - read chip data into buffer
573  * @host:	FSMC NAND controller
574  * @buf:	buffer to store date
575  * @len:	number of bytes to read
576  */
577 static void fsmc_read_buf_dma(struct fsmc_nand_data *host, u8 *buf,
578 			      int len)
579 {
580 	dma_xfer(host, buf, len, DMA_FROM_DEVICE);
581 }
582 
583 /*
584  * fsmc_write_buf_dma - write buffer to chip
585  * @host:	FSMC NAND controller
586  * @buf:	data buffer
587  * @len:	number of bytes to write
588  */
589 static void fsmc_write_buf_dma(struct fsmc_nand_data *host, const u8 *buf,
590 			       int len)
591 {
592 	dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
593 }
594 
595 /*
596  * fsmc_exec_op - hook called by the core to execute NAND operations
597  *
598  * This controller is simple enough and thus does not need to use the parser
599  * provided by the core, instead, handle every situation here.
600  */
601 static int fsmc_exec_op(struct nand_chip *chip, const struct nand_operation *op,
602 			bool check_only)
603 {
604 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
605 	const struct nand_op_instr *instr = NULL;
606 	int ret = 0;
607 	unsigned int op_id;
608 	int i;
609 
610 	if (check_only)
611 		return 0;
612 
613 	pr_debug("Executing operation [%d instructions]:\n", op->ninstrs);
614 
615 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
616 		instr = &op->instrs[op_id];
617 
618 		nand_op_trace("  ", instr);
619 
620 		switch (instr->type) {
621 		case NAND_OP_CMD_INSTR:
622 			writeb_relaxed(instr->ctx.cmd.opcode, host->cmd_va);
623 			break;
624 
625 		case NAND_OP_ADDR_INSTR:
626 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
627 				writeb_relaxed(instr->ctx.addr.addrs[i],
628 					       host->addr_va);
629 			break;
630 
631 		case NAND_OP_DATA_IN_INSTR:
632 			if (host->mode == USE_DMA_ACCESS)
633 				fsmc_read_buf_dma(host, instr->ctx.data.buf.in,
634 						  instr->ctx.data.len);
635 			else
636 				fsmc_read_buf(host, instr->ctx.data.buf.in,
637 					      instr->ctx.data.len);
638 			break;
639 
640 		case NAND_OP_DATA_OUT_INSTR:
641 			if (host->mode == USE_DMA_ACCESS)
642 				fsmc_write_buf_dma(host,
643 						   instr->ctx.data.buf.out,
644 						   instr->ctx.data.len);
645 			else
646 				fsmc_write_buf(host, instr->ctx.data.buf.out,
647 					       instr->ctx.data.len);
648 			break;
649 
650 		case NAND_OP_WAITRDY_INSTR:
651 			ret = nand_soft_waitrdy(chip,
652 						instr->ctx.waitrdy.timeout_ms);
653 			break;
654 		}
655 	}
656 
657 	return ret;
658 }
659 
660 /*
661  * fsmc_read_page_hwecc
662  * @chip:	nand chip info structure
663  * @buf:	buffer to store read data
664  * @oob_required:	caller expects OOB data read to chip->oob_poi
665  * @page:	page number to read
666  *
667  * This routine is needed for fsmc version 8 as reading from NAND chip has to be
668  * performed in a strict sequence as follows:
669  * data(512 byte) -> ecc(13 byte)
670  * After this read, fsmc hardware generates and reports error data bits(up to a
671  * max of 8 bits)
672  */
673 static int fsmc_read_page_hwecc(struct nand_chip *chip, u8 *buf,
674 				int oob_required, int page)
675 {
676 	struct mtd_info *mtd = nand_to_mtd(chip);
677 	int i, j, s, stat, eccsize = chip->ecc.size;
678 	int eccbytes = chip->ecc.bytes;
679 	int eccsteps = chip->ecc.steps;
680 	u8 *p = buf;
681 	u8 *ecc_calc = chip->ecc.calc_buf;
682 	u8 *ecc_code = chip->ecc.code_buf;
683 	int off, len, ret, group = 0;
684 	/*
685 	 * ecc_oob is intentionally taken as u16. In 16bit devices, we
686 	 * end up reading 14 bytes (7 words) from oob. The local array is
687 	 * to maintain word alignment
688 	 */
689 	u16 ecc_oob[7];
690 	u8 *oob = (u8 *)&ecc_oob[0];
691 	unsigned int max_bitflips = 0;
692 
693 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
694 		nand_read_page_op(chip, page, s * eccsize, NULL, 0);
695 		chip->ecc.hwctl(chip, NAND_ECC_READ);
696 		ret = nand_read_data_op(chip, p, eccsize, false, false);
697 		if (ret)
698 			return ret;
699 
700 		for (j = 0; j < eccbytes;) {
701 			struct mtd_oob_region oobregion;
702 
703 			ret = mtd_ooblayout_ecc(mtd, group++, &oobregion);
704 			if (ret)
705 				return ret;
706 
707 			off = oobregion.offset;
708 			len = oobregion.length;
709 
710 			/*
711 			 * length is intentionally kept a higher multiple of 2
712 			 * to read at least 13 bytes even in case of 16 bit NAND
713 			 * devices
714 			 */
715 			if (chip->options & NAND_BUSWIDTH_16)
716 				len = roundup(len, 2);
717 
718 			nand_read_oob_op(chip, page, off, oob + j, len);
719 			j += len;
720 		}
721 
722 		memcpy(&ecc_code[i], oob, chip->ecc.bytes);
723 		chip->ecc.calculate(chip, p, &ecc_calc[i]);
724 
725 		stat = chip->ecc.correct(chip, p, &ecc_code[i], &ecc_calc[i]);
726 		if (stat < 0) {
727 			mtd->ecc_stats.failed++;
728 		} else {
729 			mtd->ecc_stats.corrected += stat;
730 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
731 		}
732 	}
733 
734 	return max_bitflips;
735 }
736 
737 /*
738  * fsmc_bch8_correct_data
739  * @mtd:	mtd info structure
740  * @dat:	buffer of read data
741  * @read_ecc:	ecc read from device spare area
742  * @calc_ecc:	ecc calculated from read data
743  *
744  * calc_ecc is a 104 bit information containing maximum of 8 error
745  * offset information of 13 bits each in 512 bytes of read data.
746  */
747 static int fsmc_bch8_correct_data(struct nand_chip *chip, u8 *dat,
748 				  u8 *read_ecc, u8 *calc_ecc)
749 {
750 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
751 	u32 err_idx[8];
752 	u32 num_err, i;
753 	u32 ecc1, ecc2, ecc3, ecc4;
754 
755 	num_err = (readl_relaxed(host->regs_va + STS) >> 10) & 0xF;
756 
757 	/* no bit flipping */
758 	if (likely(num_err == 0))
759 		return 0;
760 
761 	/* too many errors */
762 	if (unlikely(num_err > 8)) {
763 		/*
764 		 * This is a temporary erase check. A newly erased page read
765 		 * would result in an ecc error because the oob data is also
766 		 * erased to FF and the calculated ecc for an FF data is not
767 		 * FF..FF.
768 		 * This is a workaround to skip performing correction in case
769 		 * data is FF..FF
770 		 *
771 		 * Logic:
772 		 * For every page, each bit written as 0 is counted until these
773 		 * number of bits are greater than 8 (the maximum correction
774 		 * capability of FSMC for each 512 + 13 bytes)
775 		 */
776 
777 		int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
778 		int bits_data = count_written_bits(dat, chip->ecc.size, 8);
779 
780 		if ((bits_ecc + bits_data) <= 8) {
781 			if (bits_data)
782 				memset(dat, 0xff, chip->ecc.size);
783 			return bits_data;
784 		}
785 
786 		return -EBADMSG;
787 	}
788 
789 	/*
790 	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
791 	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
792 	 *
793 	 * calc_ecc is a 104 bit information containing maximum of 8 error
794 	 * offset information of 13 bits each. calc_ecc is copied into a
795 	 * u64 array and error offset indexes are populated in err_idx
796 	 * array
797 	 */
798 	ecc1 = readl_relaxed(host->regs_va + ECC1);
799 	ecc2 = readl_relaxed(host->regs_va + ECC2);
800 	ecc3 = readl_relaxed(host->regs_va + ECC3);
801 	ecc4 = readl_relaxed(host->regs_va + STS);
802 
803 	err_idx[0] = (ecc1 >> 0) & 0x1FFF;
804 	err_idx[1] = (ecc1 >> 13) & 0x1FFF;
805 	err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
806 	err_idx[3] = (ecc2 >> 7) & 0x1FFF;
807 	err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
808 	err_idx[5] = (ecc3 >> 1) & 0x1FFF;
809 	err_idx[6] = (ecc3 >> 14) & 0x1FFF;
810 	err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
811 
812 	i = 0;
813 	while (num_err--) {
814 		err_idx[i] ^= 3;
815 
816 		if (err_idx[i] < chip->ecc.size * 8) {
817 			int err = err_idx[i];
818 
819 			dat[err >> 3] ^= BIT(err & 7);
820 			i++;
821 		}
822 	}
823 	return i;
824 }
825 
826 static bool filter(struct dma_chan *chan, void *slave)
827 {
828 	chan->private = slave;
829 	return true;
830 }
831 
832 static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
833 				     struct fsmc_nand_data *host,
834 				     struct nand_chip *nand)
835 {
836 	struct device_node *np = pdev->dev.of_node;
837 	u32 val;
838 	int ret;
839 
840 	nand->options = 0;
841 
842 	if (!of_property_read_u32(np, "bank-width", &val)) {
843 		if (val == 2) {
844 			nand->options |= NAND_BUSWIDTH_16;
845 		} else if (val != 1) {
846 			dev_err(&pdev->dev, "invalid bank-width %u\n", val);
847 			return -EINVAL;
848 		}
849 	}
850 
851 	if (of_get_property(np, "nand-skip-bbtscan", NULL))
852 		nand->options |= NAND_SKIP_BBTSCAN;
853 
854 	host->dev_timings = devm_kzalloc(&pdev->dev,
855 					 sizeof(*host->dev_timings),
856 					 GFP_KERNEL);
857 	if (!host->dev_timings)
858 		return -ENOMEM;
859 
860 	ret = of_property_read_u8_array(np, "timings", (u8 *)host->dev_timings,
861 					sizeof(*host->dev_timings));
862 	if (ret)
863 		host->dev_timings = NULL;
864 
865 	/* Set default NAND bank to 0 */
866 	host->bank = 0;
867 	if (!of_property_read_u32(np, "bank", &val)) {
868 		if (val > 3) {
869 			dev_err(&pdev->dev, "invalid bank %u\n", val);
870 			return -EINVAL;
871 		}
872 		host->bank = val;
873 	}
874 	return 0;
875 }
876 
877 static int fsmc_nand_attach_chip(struct nand_chip *nand)
878 {
879 	struct mtd_info *mtd = nand_to_mtd(nand);
880 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
881 
882 	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_INVALID)
883 		nand->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
884 
885 	if (!nand->ecc.size)
886 		nand->ecc.size = 512;
887 
888 	if (AMBA_REV_BITS(host->pid) >= 8) {
889 		nand->ecc.read_page = fsmc_read_page_hwecc;
890 		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
891 		nand->ecc.correct = fsmc_bch8_correct_data;
892 		nand->ecc.bytes = 13;
893 		nand->ecc.strength = 8;
894 	}
895 
896 	if (AMBA_REV_BITS(host->pid) >= 8) {
897 		switch (mtd->oobsize) {
898 		case 16:
899 		case 64:
900 		case 128:
901 		case 224:
902 		case 256:
903 			break;
904 		default:
905 			dev_warn(host->dev,
906 				 "No oob scheme defined for oobsize %d\n",
907 				 mtd->oobsize);
908 			return -EINVAL;
909 		}
910 
911 		mtd_set_ooblayout(mtd, &fsmc_ecc4_ooblayout_ops);
912 
913 		return 0;
914 	}
915 
916 	switch (nand->ecc.engine_type) {
917 	case NAND_ECC_ENGINE_TYPE_ON_HOST:
918 		dev_info(host->dev, "Using 1-bit HW ECC scheme\n");
919 		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
920 		nand->ecc.correct = rawnand_sw_hamming_correct;
921 		nand->ecc.hwctl = fsmc_enable_hwecc;
922 		nand->ecc.bytes = 3;
923 		nand->ecc.strength = 1;
924 		nand->ecc.options |= NAND_ECC_SOFT_HAMMING_SM_ORDER;
925 		break;
926 
927 	case NAND_ECC_ENGINE_TYPE_SOFT:
928 		if (nand->ecc.algo == NAND_ECC_ALGO_BCH) {
929 			dev_info(host->dev,
930 				 "Using 4-bit SW BCH ECC scheme\n");
931 			break;
932 		}
933 		break;
934 
935 	case NAND_ECC_ENGINE_TYPE_ON_DIE:
936 		break;
937 
938 	default:
939 		dev_err(host->dev, "Unsupported ECC mode!\n");
940 		return -ENOTSUPP;
941 	}
942 
943 	/*
944 	 * Don't set layout for BCH4 SW ECC. This will be
945 	 * generated later during BCH initialization.
946 	 */
947 	if (nand->ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST) {
948 		switch (mtd->oobsize) {
949 		case 16:
950 		case 64:
951 		case 128:
952 			mtd_set_ooblayout(mtd,
953 					  &fsmc_ecc1_ooblayout_ops);
954 			break;
955 		default:
956 			dev_warn(host->dev,
957 				 "No oob scheme defined for oobsize %d\n",
958 				 mtd->oobsize);
959 			return -EINVAL;
960 		}
961 	}
962 
963 	return 0;
964 }
965 
966 static const struct nand_controller_ops fsmc_nand_controller_ops = {
967 	.attach_chip = fsmc_nand_attach_chip,
968 	.exec_op = fsmc_exec_op,
969 	.setup_interface = fsmc_setup_interface,
970 };
971 
972 /**
973  * fsmc_nand_disable() - Disables the NAND bank
974  * @host: The instance to disable
975  */
976 static void fsmc_nand_disable(struct fsmc_nand_data *host)
977 {
978 	u32 val;
979 
980 	val = readl(host->regs_va + FSMC_PC);
981 	val &= ~FSMC_ENABLE;
982 	writel(val, host->regs_va + FSMC_PC);
983 }
984 
985 /*
986  * fsmc_nand_probe - Probe function
987  * @pdev:       platform device structure
988  */
989 static int __init fsmc_nand_probe(struct platform_device *pdev)
990 {
991 	struct fsmc_nand_data *host;
992 	struct mtd_info *mtd;
993 	struct nand_chip *nand;
994 	struct resource *res;
995 	void __iomem *base;
996 	dma_cap_mask_t mask;
997 	int ret = 0;
998 	u32 pid;
999 	int i;
1000 
1001 	/* Allocate memory for the device structure (and zero it) */
1002 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
1003 	if (!host)
1004 		return -ENOMEM;
1005 
1006 	nand = &host->nand;
1007 
1008 	ret = fsmc_nand_probe_config_dt(pdev, host, nand);
1009 	if (ret)
1010 		return ret;
1011 
1012 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
1013 	host->data_va = devm_ioremap_resource(&pdev->dev, res);
1014 	if (IS_ERR(host->data_va))
1015 		return PTR_ERR(host->data_va);
1016 
1017 	host->data_pa = (dma_addr_t)res->start;
1018 
1019 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
1020 	host->addr_va = devm_ioremap_resource(&pdev->dev, res);
1021 	if (IS_ERR(host->addr_va))
1022 		return PTR_ERR(host->addr_va);
1023 
1024 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
1025 	host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
1026 	if (IS_ERR(host->cmd_va))
1027 		return PTR_ERR(host->cmd_va);
1028 
1029 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
1030 	base = devm_ioremap_resource(&pdev->dev, res);
1031 	if (IS_ERR(base))
1032 		return PTR_ERR(base);
1033 
1034 	host->regs_va = base + FSMC_NOR_REG_SIZE +
1035 		(host->bank * FSMC_NAND_BANK_SZ);
1036 
1037 	host->clk = devm_clk_get(&pdev->dev, NULL);
1038 	if (IS_ERR(host->clk)) {
1039 		dev_err(&pdev->dev, "failed to fetch block clock\n");
1040 		return PTR_ERR(host->clk);
1041 	}
1042 
1043 	ret = clk_prepare_enable(host->clk);
1044 	if (ret)
1045 		return ret;
1046 
1047 	/*
1048 	 * This device ID is actually a common AMBA ID as used on the
1049 	 * AMBA PrimeCell bus. However it is not a PrimeCell.
1050 	 */
1051 	for (pid = 0, i = 0; i < 4; i++)
1052 		pid |= (readl(base + resource_size(res) - 0x20 + 4 * i) &
1053 			255) << (i * 8);
1054 
1055 	host->pid = pid;
1056 
1057 	dev_info(&pdev->dev,
1058 		 "FSMC device partno %03x, manufacturer %02x, revision %02x, config %02x\n",
1059 		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
1060 		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
1061 
1062 	host->dev = &pdev->dev;
1063 
1064 	if (host->mode == USE_DMA_ACCESS)
1065 		init_completion(&host->dma_access_complete);
1066 
1067 	/* Link all private pointers */
1068 	mtd = nand_to_mtd(&host->nand);
1069 	nand_set_flash_node(nand, pdev->dev.of_node);
1070 
1071 	mtd->dev.parent = &pdev->dev;
1072 
1073 	nand->badblockbits = 7;
1074 
1075 	if (host->mode == USE_DMA_ACCESS) {
1076 		dma_cap_zero(mask);
1077 		dma_cap_set(DMA_MEMCPY, mask);
1078 		host->read_dma_chan = dma_request_channel(mask, filter, NULL);
1079 		if (!host->read_dma_chan) {
1080 			dev_err(&pdev->dev, "Unable to get read dma channel\n");
1081 			ret = -ENODEV;
1082 			goto disable_clk;
1083 		}
1084 		host->write_dma_chan = dma_request_channel(mask, filter, NULL);
1085 		if (!host->write_dma_chan) {
1086 			dev_err(&pdev->dev, "Unable to get write dma channel\n");
1087 			ret = -ENODEV;
1088 			goto release_dma_read_chan;
1089 		}
1090 	}
1091 
1092 	if (host->dev_timings) {
1093 		fsmc_nand_setup(host, host->dev_timings);
1094 		nand->options |= NAND_KEEP_TIMINGS;
1095 	}
1096 
1097 	nand_controller_init(&host->base);
1098 	host->base.ops = &fsmc_nand_controller_ops;
1099 	nand->controller = &host->base;
1100 
1101 	/*
1102 	 * Scan to find existence of the device
1103 	 */
1104 	ret = nand_scan(nand, 1);
1105 	if (ret)
1106 		goto release_dma_write_chan;
1107 
1108 	mtd->name = "nand";
1109 	ret = mtd_device_register(mtd, NULL, 0);
1110 	if (ret)
1111 		goto cleanup_nand;
1112 
1113 	platform_set_drvdata(pdev, host);
1114 	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
1115 
1116 	return 0;
1117 
1118 cleanup_nand:
1119 	nand_cleanup(nand);
1120 release_dma_write_chan:
1121 	if (host->mode == USE_DMA_ACCESS)
1122 		dma_release_channel(host->write_dma_chan);
1123 release_dma_read_chan:
1124 	if (host->mode == USE_DMA_ACCESS)
1125 		dma_release_channel(host->read_dma_chan);
1126 disable_clk:
1127 	fsmc_nand_disable(host);
1128 	clk_disable_unprepare(host->clk);
1129 
1130 	return ret;
1131 }
1132 
1133 /*
1134  * Clean up routine
1135  */
1136 static int fsmc_nand_remove(struct platform_device *pdev)
1137 {
1138 	struct fsmc_nand_data *host = platform_get_drvdata(pdev);
1139 
1140 	if (host) {
1141 		struct nand_chip *chip = &host->nand;
1142 		int ret;
1143 
1144 		ret = mtd_device_unregister(nand_to_mtd(chip));
1145 		WARN_ON(ret);
1146 		nand_cleanup(chip);
1147 		fsmc_nand_disable(host);
1148 
1149 		if (host->mode == USE_DMA_ACCESS) {
1150 			dma_release_channel(host->write_dma_chan);
1151 			dma_release_channel(host->read_dma_chan);
1152 		}
1153 		clk_disable_unprepare(host->clk);
1154 	}
1155 
1156 	return 0;
1157 }
1158 
1159 #ifdef CONFIG_PM_SLEEP
1160 static int fsmc_nand_suspend(struct device *dev)
1161 {
1162 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1163 
1164 	if (host)
1165 		clk_disable_unprepare(host->clk);
1166 
1167 	return 0;
1168 }
1169 
1170 static int fsmc_nand_resume(struct device *dev)
1171 {
1172 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1173 
1174 	if (host) {
1175 		clk_prepare_enable(host->clk);
1176 		if (host->dev_timings)
1177 			fsmc_nand_setup(host, host->dev_timings);
1178 		nand_reset(&host->nand, 0);
1179 	}
1180 
1181 	return 0;
1182 }
1183 #endif
1184 
1185 static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
1186 
1187 static const struct of_device_id fsmc_nand_id_table[] = {
1188 	{ .compatible = "st,spear600-fsmc-nand" },
1189 	{ .compatible = "stericsson,fsmc-nand" },
1190 	{}
1191 };
1192 MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
1193 
1194 static struct platform_driver fsmc_nand_driver = {
1195 	.remove = fsmc_nand_remove,
1196 	.driver = {
1197 		.name = "fsmc-nand",
1198 		.of_match_table = fsmc_nand_id_table,
1199 		.pm = &fsmc_nand_pm_ops,
1200 	},
1201 };
1202 
1203 module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
1204 
1205 MODULE_LICENSE("GPL v2");
1206 MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
1207 MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");
1208