xref: /openbmc/linux/drivers/mtd/nand/raw/mtk_nand.c (revision 8e2a46a4)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * MTK NAND Flash controller driver.
4  * Copyright (C) 2016 MediaTek Inc.
5  * Authors:	Xiaolei Li		<xiaolei.li@mediatek.com>
6  *		Jorge Ramirez-Ortiz	<jorge.ramirez-ortiz@linaro.org>
7  */
8 
9 #include <linux/platform_device.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/interrupt.h>
12 #include <linux/delay.h>
13 #include <linux/clk.h>
14 #include <linux/mtd/rawnand.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/module.h>
17 #include <linux/iopoll.h>
18 #include <linux/of.h>
19 #include <linux/of_device.h>
20 #include "mtk_ecc.h"
21 
22 /* NAND controller register definition */
23 #define NFI_CNFG		(0x00)
24 #define		CNFG_AHB		BIT(0)
25 #define		CNFG_READ_EN		BIT(1)
26 #define		CNFG_DMA_BURST_EN	BIT(2)
27 #define		CNFG_BYTE_RW		BIT(6)
28 #define		CNFG_HW_ECC_EN		BIT(8)
29 #define		CNFG_AUTO_FMT_EN	BIT(9)
30 #define		CNFG_OP_CUST		(6 << 12)
31 #define NFI_PAGEFMT		(0x04)
32 #define		PAGEFMT_FDM_ECC_SHIFT	(12)
33 #define		PAGEFMT_FDM_SHIFT	(8)
34 #define		PAGEFMT_SEC_SEL_512	BIT(2)
35 #define		PAGEFMT_512_2K		(0)
36 #define		PAGEFMT_2K_4K		(1)
37 #define		PAGEFMT_4K_8K		(2)
38 #define		PAGEFMT_8K_16K		(3)
39 /* NFI control */
40 #define NFI_CON			(0x08)
41 #define		CON_FIFO_FLUSH		BIT(0)
42 #define		CON_NFI_RST		BIT(1)
43 #define		CON_BRD			BIT(8)  /* burst  read */
44 #define		CON_BWR			BIT(9)	/* burst  write */
45 #define		CON_SEC_SHIFT		(12)
46 /* Timming control register */
47 #define NFI_ACCCON		(0x0C)
48 #define NFI_INTR_EN		(0x10)
49 #define		INTR_AHB_DONE_EN	BIT(6)
50 #define NFI_INTR_STA		(0x14)
51 #define NFI_CMD			(0x20)
52 #define NFI_ADDRNOB		(0x30)
53 #define NFI_COLADDR		(0x34)
54 #define NFI_ROWADDR		(0x38)
55 #define NFI_STRDATA		(0x40)
56 #define		STAR_EN			(1)
57 #define		STAR_DE			(0)
58 #define NFI_CNRNB		(0x44)
59 #define NFI_DATAW		(0x50)
60 #define NFI_DATAR		(0x54)
61 #define NFI_PIO_DIRDY		(0x58)
62 #define		PIO_DI_RDY		(0x01)
63 #define NFI_STA			(0x60)
64 #define		STA_CMD			BIT(0)
65 #define		STA_ADDR		BIT(1)
66 #define		STA_BUSY		BIT(8)
67 #define		STA_EMP_PAGE		BIT(12)
68 #define		NFI_FSM_CUSTDATA	(0xe << 16)
69 #define		NFI_FSM_MASK		(0xf << 16)
70 #define NFI_ADDRCNTR		(0x70)
71 #define		CNTR_MASK		GENMASK(16, 12)
72 #define		ADDRCNTR_SEC_SHIFT	(12)
73 #define		ADDRCNTR_SEC(val) \
74 		(((val) & CNTR_MASK) >> ADDRCNTR_SEC_SHIFT)
75 #define NFI_STRADDR		(0x80)
76 #define NFI_BYTELEN		(0x84)
77 #define NFI_CSEL		(0x90)
78 #define NFI_FDML(x)		(0xA0 + (x) * sizeof(u32) * 2)
79 #define NFI_FDMM(x)		(0xA4 + (x) * sizeof(u32) * 2)
80 #define NFI_FDM_MAX_SIZE	(8)
81 #define NFI_FDM_MIN_SIZE	(1)
82 #define NFI_DEBUG_CON1		(0x220)
83 #define		STROBE_MASK		GENMASK(4, 3)
84 #define		STROBE_SHIFT		(3)
85 #define		MAX_STROBE_DLY		(3)
86 #define NFI_MASTER_STA		(0x224)
87 #define		MASTER_STA_MASK		(0x0FFF)
88 #define NFI_EMPTY_THRESH	(0x23C)
89 
90 #define MTK_NAME		"mtk-nand"
91 #define KB(x)			((x) * 1024UL)
92 #define MB(x)			(KB(x) * 1024UL)
93 
94 #define MTK_TIMEOUT		(500000)
95 #define MTK_RESET_TIMEOUT	(1000000)
96 #define MTK_NAND_MAX_NSELS	(2)
97 #define MTK_NFC_MIN_SPARE	(16)
98 #define ACCTIMING(tpoecs, tprecs, tc2r, tw2r, twh, twst, trlt) \
99 	((tpoecs) << 28 | (tprecs) << 22 | (tc2r) << 16 | \
100 	(tw2r) << 12 | (twh) << 8 | (twst) << 4 | (trlt))
101 
102 struct mtk_nfc_caps {
103 	const u8 *spare_size;
104 	u8 num_spare_size;
105 	u8 pageformat_spare_shift;
106 	u8 nfi_clk_div;
107 	u8 max_sector;
108 	u32 max_sector_size;
109 };
110 
111 struct mtk_nfc_bad_mark_ctl {
112 	void (*bm_swap)(struct mtd_info *, u8 *buf, int raw);
113 	u32 sec;
114 	u32 pos;
115 };
116 
117 /*
118  * FDM: region used to store free OOB data
119  */
120 struct mtk_nfc_fdm {
121 	u32 reg_size;
122 	u32 ecc_size;
123 };
124 
125 struct mtk_nfc_nand_chip {
126 	struct list_head node;
127 	struct nand_chip nand;
128 
129 	struct mtk_nfc_bad_mark_ctl bad_mark;
130 	struct mtk_nfc_fdm fdm;
131 	u32 spare_per_sector;
132 
133 	int nsels;
134 	u8 sels[];
135 	/* nothing after this field */
136 };
137 
138 struct mtk_nfc_clk {
139 	struct clk *nfi_clk;
140 	struct clk *pad_clk;
141 };
142 
143 struct mtk_nfc {
144 	struct nand_controller controller;
145 	struct mtk_ecc_config ecc_cfg;
146 	struct mtk_nfc_clk clk;
147 	struct mtk_ecc *ecc;
148 
149 	struct device *dev;
150 	const struct mtk_nfc_caps *caps;
151 	void __iomem *regs;
152 
153 	struct completion done;
154 	struct list_head chips;
155 
156 	u8 *buffer;
157 
158 	unsigned long assigned_cs;
159 };
160 
161 /*
162  * supported spare size of each IP.
163  * order should be the same with the spare size bitfiled defination of
164  * register NFI_PAGEFMT.
165  */
166 static const u8 spare_size_mt2701[] = {
167 	16, 26, 27, 28, 32, 36, 40, 44,	48, 49, 50, 51, 52, 62, 63, 64
168 };
169 
170 static const u8 spare_size_mt2712[] = {
171 	16, 26, 27, 28, 32, 36, 40, 44, 48, 49, 50, 51, 52, 62, 61, 63, 64, 67,
172 	74
173 };
174 
175 static const u8 spare_size_mt7622[] = {
176 	16, 26, 27, 28
177 };
178 
179 static inline struct mtk_nfc_nand_chip *to_mtk_nand(struct nand_chip *nand)
180 {
181 	return container_of(nand, struct mtk_nfc_nand_chip, nand);
182 }
183 
184 static inline u8 *data_ptr(struct nand_chip *chip, const u8 *p, int i)
185 {
186 	return (u8 *)p + i * chip->ecc.size;
187 }
188 
189 static inline u8 *oob_ptr(struct nand_chip *chip, int i)
190 {
191 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
192 	u8 *poi;
193 
194 	/* map the sector's FDM data to free oob:
195 	 * the beginning of the oob area stores the FDM data of bad mark sectors
196 	 */
197 
198 	if (i < mtk_nand->bad_mark.sec)
199 		poi = chip->oob_poi + (i + 1) * mtk_nand->fdm.reg_size;
200 	else if (i == mtk_nand->bad_mark.sec)
201 		poi = chip->oob_poi;
202 	else
203 		poi = chip->oob_poi + i * mtk_nand->fdm.reg_size;
204 
205 	return poi;
206 }
207 
208 static inline int mtk_data_len(struct nand_chip *chip)
209 {
210 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
211 
212 	return chip->ecc.size + mtk_nand->spare_per_sector;
213 }
214 
215 static inline u8 *mtk_data_ptr(struct nand_chip *chip,  int i)
216 {
217 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
218 
219 	return nfc->buffer + i * mtk_data_len(chip);
220 }
221 
222 static inline u8 *mtk_oob_ptr(struct nand_chip *chip, int i)
223 {
224 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
225 
226 	return nfc->buffer + i * mtk_data_len(chip) + chip->ecc.size;
227 }
228 
229 static inline void nfi_writel(struct mtk_nfc *nfc, u32 val, u32 reg)
230 {
231 	writel(val, nfc->regs + reg);
232 }
233 
234 static inline void nfi_writew(struct mtk_nfc *nfc, u16 val, u32 reg)
235 {
236 	writew(val, nfc->regs + reg);
237 }
238 
239 static inline void nfi_writeb(struct mtk_nfc *nfc, u8 val, u32 reg)
240 {
241 	writeb(val, nfc->regs + reg);
242 }
243 
244 static inline u32 nfi_readl(struct mtk_nfc *nfc, u32 reg)
245 {
246 	return readl_relaxed(nfc->regs + reg);
247 }
248 
249 static inline u16 nfi_readw(struct mtk_nfc *nfc, u32 reg)
250 {
251 	return readw_relaxed(nfc->regs + reg);
252 }
253 
254 static inline u8 nfi_readb(struct mtk_nfc *nfc, u32 reg)
255 {
256 	return readb_relaxed(nfc->regs + reg);
257 }
258 
259 static void mtk_nfc_hw_reset(struct mtk_nfc *nfc)
260 {
261 	struct device *dev = nfc->dev;
262 	u32 val;
263 	int ret;
264 
265 	/* reset all registers and force the NFI master to terminate */
266 	nfi_writel(nfc, CON_FIFO_FLUSH | CON_NFI_RST, NFI_CON);
267 
268 	/* wait for the master to finish the last transaction */
269 	ret = readl_poll_timeout(nfc->regs + NFI_MASTER_STA, val,
270 				 !(val & MASTER_STA_MASK), 50,
271 				 MTK_RESET_TIMEOUT);
272 	if (ret)
273 		dev_warn(dev, "master active in reset [0x%x] = 0x%x\n",
274 			 NFI_MASTER_STA, val);
275 
276 	/* ensure any status register affected by the NFI master is reset */
277 	nfi_writel(nfc, CON_FIFO_FLUSH | CON_NFI_RST, NFI_CON);
278 	nfi_writew(nfc, STAR_DE, NFI_STRDATA);
279 }
280 
281 static int mtk_nfc_send_command(struct mtk_nfc *nfc, u8 command)
282 {
283 	struct device *dev = nfc->dev;
284 	u32 val;
285 	int ret;
286 
287 	nfi_writel(nfc, command, NFI_CMD);
288 
289 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_STA, val,
290 					!(val & STA_CMD), 10,  MTK_TIMEOUT);
291 	if (ret) {
292 		dev_warn(dev, "nfi core timed out entering command mode\n");
293 		return -EIO;
294 	}
295 
296 	return 0;
297 }
298 
299 static int mtk_nfc_send_address(struct mtk_nfc *nfc, int addr)
300 {
301 	struct device *dev = nfc->dev;
302 	u32 val;
303 	int ret;
304 
305 	nfi_writel(nfc, addr, NFI_COLADDR);
306 	nfi_writel(nfc, 0, NFI_ROWADDR);
307 	nfi_writew(nfc, 1, NFI_ADDRNOB);
308 
309 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_STA, val,
310 					!(val & STA_ADDR), 10, MTK_TIMEOUT);
311 	if (ret) {
312 		dev_warn(dev, "nfi core timed out entering address mode\n");
313 		return -EIO;
314 	}
315 
316 	return 0;
317 }
318 
319 static int mtk_nfc_hw_runtime_config(struct mtd_info *mtd)
320 {
321 	struct nand_chip *chip = mtd_to_nand(mtd);
322 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
323 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
324 	u32 fmt, spare, i;
325 
326 	if (!mtd->writesize)
327 		return 0;
328 
329 	spare = mtk_nand->spare_per_sector;
330 
331 	switch (mtd->writesize) {
332 	case 512:
333 		fmt = PAGEFMT_512_2K | PAGEFMT_SEC_SEL_512;
334 		break;
335 	case KB(2):
336 		if (chip->ecc.size == 512)
337 			fmt = PAGEFMT_2K_4K | PAGEFMT_SEC_SEL_512;
338 		else
339 			fmt = PAGEFMT_512_2K;
340 		break;
341 	case KB(4):
342 		if (chip->ecc.size == 512)
343 			fmt = PAGEFMT_4K_8K | PAGEFMT_SEC_SEL_512;
344 		else
345 			fmt = PAGEFMT_2K_4K;
346 		break;
347 	case KB(8):
348 		if (chip->ecc.size == 512)
349 			fmt = PAGEFMT_8K_16K | PAGEFMT_SEC_SEL_512;
350 		else
351 			fmt = PAGEFMT_4K_8K;
352 		break;
353 	case KB(16):
354 		fmt = PAGEFMT_8K_16K;
355 		break;
356 	default:
357 		dev_err(nfc->dev, "invalid page len: %d\n", mtd->writesize);
358 		return -EINVAL;
359 	}
360 
361 	/*
362 	 * the hardware will double the value for this eccsize, so we need to
363 	 * halve it
364 	 */
365 	if (chip->ecc.size == 1024)
366 		spare >>= 1;
367 
368 	for (i = 0; i < nfc->caps->num_spare_size; i++) {
369 		if (nfc->caps->spare_size[i] == spare)
370 			break;
371 	}
372 
373 	if (i == nfc->caps->num_spare_size) {
374 		dev_err(nfc->dev, "invalid spare size %d\n", spare);
375 		return -EINVAL;
376 	}
377 
378 	fmt |= i << nfc->caps->pageformat_spare_shift;
379 
380 	fmt |= mtk_nand->fdm.reg_size << PAGEFMT_FDM_SHIFT;
381 	fmt |= mtk_nand->fdm.ecc_size << PAGEFMT_FDM_ECC_SHIFT;
382 	nfi_writel(nfc, fmt, NFI_PAGEFMT);
383 
384 	nfc->ecc_cfg.strength = chip->ecc.strength;
385 	nfc->ecc_cfg.len = chip->ecc.size + mtk_nand->fdm.ecc_size;
386 
387 	return 0;
388 }
389 
390 static void mtk_nfc_select_chip(struct nand_chip *nand, int chip)
391 {
392 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
393 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(nand);
394 
395 	if (chip < 0)
396 		return;
397 
398 	mtk_nfc_hw_runtime_config(nand_to_mtd(nand));
399 
400 	nfi_writel(nfc, mtk_nand->sels[chip], NFI_CSEL);
401 }
402 
403 static int mtk_nfc_dev_ready(struct nand_chip *nand)
404 {
405 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
406 
407 	if (nfi_readl(nfc, NFI_STA) & STA_BUSY)
408 		return 0;
409 
410 	return 1;
411 }
412 
413 static void mtk_nfc_cmd_ctrl(struct nand_chip *chip, int dat,
414 			     unsigned int ctrl)
415 {
416 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
417 
418 	if (ctrl & NAND_ALE) {
419 		mtk_nfc_send_address(nfc, dat);
420 	} else if (ctrl & NAND_CLE) {
421 		mtk_nfc_hw_reset(nfc);
422 
423 		nfi_writew(nfc, CNFG_OP_CUST, NFI_CNFG);
424 		mtk_nfc_send_command(nfc, dat);
425 	}
426 }
427 
428 static inline void mtk_nfc_wait_ioready(struct mtk_nfc *nfc)
429 {
430 	int rc;
431 	u8 val;
432 
433 	rc = readb_poll_timeout_atomic(nfc->regs + NFI_PIO_DIRDY, val,
434 				       val & PIO_DI_RDY, 10, MTK_TIMEOUT);
435 	if (rc < 0)
436 		dev_err(nfc->dev, "data not ready\n");
437 }
438 
439 static inline u8 mtk_nfc_read_byte(struct nand_chip *chip)
440 {
441 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
442 	u32 reg;
443 
444 	/* after each byte read, the NFI_STA reg is reset by the hardware */
445 	reg = nfi_readl(nfc, NFI_STA) & NFI_FSM_MASK;
446 	if (reg != NFI_FSM_CUSTDATA) {
447 		reg = nfi_readw(nfc, NFI_CNFG);
448 		reg |= CNFG_BYTE_RW | CNFG_READ_EN;
449 		nfi_writew(nfc, reg, NFI_CNFG);
450 
451 		/*
452 		 * set to max sector to allow the HW to continue reading over
453 		 * unaligned accesses
454 		 */
455 		reg = (nfc->caps->max_sector << CON_SEC_SHIFT) | CON_BRD;
456 		nfi_writel(nfc, reg, NFI_CON);
457 
458 		/* trigger to fetch data */
459 		nfi_writew(nfc, STAR_EN, NFI_STRDATA);
460 	}
461 
462 	mtk_nfc_wait_ioready(nfc);
463 
464 	return nfi_readb(nfc, NFI_DATAR);
465 }
466 
467 static void mtk_nfc_read_buf(struct nand_chip *chip, u8 *buf, int len)
468 {
469 	int i;
470 
471 	for (i = 0; i < len; i++)
472 		buf[i] = mtk_nfc_read_byte(chip);
473 }
474 
475 static void mtk_nfc_write_byte(struct nand_chip *chip, u8 byte)
476 {
477 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
478 	u32 reg;
479 
480 	reg = nfi_readl(nfc, NFI_STA) & NFI_FSM_MASK;
481 
482 	if (reg != NFI_FSM_CUSTDATA) {
483 		reg = nfi_readw(nfc, NFI_CNFG) | CNFG_BYTE_RW;
484 		nfi_writew(nfc, reg, NFI_CNFG);
485 
486 		reg = nfc->caps->max_sector << CON_SEC_SHIFT | CON_BWR;
487 		nfi_writel(nfc, reg, NFI_CON);
488 
489 		nfi_writew(nfc, STAR_EN, NFI_STRDATA);
490 	}
491 
492 	mtk_nfc_wait_ioready(nfc);
493 	nfi_writeb(nfc, byte, NFI_DATAW);
494 }
495 
496 static void mtk_nfc_write_buf(struct nand_chip *chip, const u8 *buf, int len)
497 {
498 	int i;
499 
500 	for (i = 0; i < len; i++)
501 		mtk_nfc_write_byte(chip, buf[i]);
502 }
503 
504 static int mtk_nfc_setup_data_interface(struct nand_chip *chip, int csline,
505 					const struct nand_data_interface *conf)
506 {
507 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
508 	const struct nand_sdr_timings *timings;
509 	u32 rate, tpoecs, tprecs, tc2r, tw2r, twh, twst = 0, trlt = 0;
510 	u32 temp, tsel = 0;
511 
512 	timings = nand_get_sdr_timings(conf);
513 	if (IS_ERR(timings))
514 		return -ENOTSUPP;
515 
516 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
517 		return 0;
518 
519 	rate = clk_get_rate(nfc->clk.nfi_clk);
520 	/* There is a frequency divider in some IPs */
521 	rate /= nfc->caps->nfi_clk_div;
522 
523 	/* turn clock rate into KHZ */
524 	rate /= 1000;
525 
526 	tpoecs = max(timings->tALH_min, timings->tCLH_min) / 1000;
527 	tpoecs = DIV_ROUND_UP(tpoecs * rate, 1000000);
528 	tpoecs &= 0xf;
529 
530 	tprecs = max(timings->tCLS_min, timings->tALS_min) / 1000;
531 	tprecs = DIV_ROUND_UP(tprecs * rate, 1000000);
532 	tprecs &= 0x3f;
533 
534 	/* sdr interface has no tCR which means CE# low to RE# low */
535 	tc2r = 0;
536 
537 	tw2r = timings->tWHR_min / 1000;
538 	tw2r = DIV_ROUND_UP(tw2r * rate, 1000000);
539 	tw2r = DIV_ROUND_UP(tw2r - 1, 2);
540 	tw2r &= 0xf;
541 
542 	twh = max(timings->tREH_min, timings->tWH_min) / 1000;
543 	twh = DIV_ROUND_UP(twh * rate, 1000000) - 1;
544 	twh &= 0xf;
545 
546 	/* Calculate real WE#/RE# hold time in nanosecond */
547 	temp = (twh + 1) * 1000000 / rate;
548 	/* nanosecond to picosecond */
549 	temp *= 1000;
550 
551 	/*
552 	 * WE# low level time should be expaned to meet WE# pulse time
553 	 * and WE# cycle time at the same time.
554 	 */
555 	if (temp < timings->tWC_min)
556 		twst = timings->tWC_min - temp;
557 	twst = max(timings->tWP_min, twst) / 1000;
558 	twst = DIV_ROUND_UP(twst * rate, 1000000) - 1;
559 	twst &= 0xf;
560 
561 	/*
562 	 * RE# low level time should be expaned to meet RE# pulse time
563 	 * and RE# cycle time at the same time.
564 	 */
565 	if (temp < timings->tRC_min)
566 		trlt = timings->tRC_min - temp;
567 	trlt = max(trlt, timings->tRP_min) / 1000;
568 	trlt = DIV_ROUND_UP(trlt * rate, 1000000) - 1;
569 	trlt &= 0xf;
570 
571 	/* Calculate RE# pulse time in nanosecond. */
572 	temp = (trlt + 1) * 1000000 / rate;
573 	/* nanosecond to picosecond */
574 	temp *= 1000;
575 	/*
576 	 * If RE# access time is bigger than RE# pulse time,
577 	 * delay sampling data timing.
578 	 */
579 	if (temp < timings->tREA_max) {
580 		tsel = timings->tREA_max / 1000;
581 		tsel = DIV_ROUND_UP(tsel * rate, 1000000);
582 		tsel -= (trlt + 1);
583 		if (tsel > MAX_STROBE_DLY) {
584 			trlt += tsel - MAX_STROBE_DLY;
585 			tsel = MAX_STROBE_DLY;
586 		}
587 	}
588 	temp = nfi_readl(nfc, NFI_DEBUG_CON1);
589 	temp &= ~STROBE_MASK;
590 	temp |= tsel << STROBE_SHIFT;
591 	nfi_writel(nfc, temp, NFI_DEBUG_CON1);
592 
593 	/*
594 	 * ACCON: access timing control register
595 	 * -------------------------------------
596 	 * 31:28: tpoecs, minimum required time for CS post pulling down after
597 	 *        accessing the device
598 	 * 27:22: tprecs, minimum required time for CS pre pulling down before
599 	 *        accessing the device
600 	 * 21:16: tc2r, minimum required time from NCEB low to NREB low
601 	 * 15:12: tw2r, minimum required time from NWEB high to NREB low.
602 	 * 11:08: twh, write enable hold time
603 	 * 07:04: twst, write wait states
604 	 * 03:00: trlt, read wait states
605 	 */
606 	trlt = ACCTIMING(tpoecs, tprecs, tc2r, tw2r, twh, twst, trlt);
607 	nfi_writel(nfc, trlt, NFI_ACCCON);
608 
609 	return 0;
610 }
611 
612 static int mtk_nfc_sector_encode(struct nand_chip *chip, u8 *data)
613 {
614 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
615 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
616 	int size = chip->ecc.size + mtk_nand->fdm.reg_size;
617 
618 	nfc->ecc_cfg.mode = ECC_DMA_MODE;
619 	nfc->ecc_cfg.op = ECC_ENCODE;
620 
621 	return mtk_ecc_encode(nfc->ecc, &nfc->ecc_cfg, data, size);
622 }
623 
624 static void mtk_nfc_no_bad_mark_swap(struct mtd_info *a, u8 *b, int c)
625 {
626 	/* nop */
627 }
628 
629 static void mtk_nfc_bad_mark_swap(struct mtd_info *mtd, u8 *buf, int raw)
630 {
631 	struct nand_chip *chip = mtd_to_nand(mtd);
632 	struct mtk_nfc_nand_chip *nand = to_mtk_nand(chip);
633 	u32 bad_pos = nand->bad_mark.pos;
634 
635 	if (raw)
636 		bad_pos += nand->bad_mark.sec * mtk_data_len(chip);
637 	else
638 		bad_pos += nand->bad_mark.sec * chip->ecc.size;
639 
640 	swap(chip->oob_poi[0], buf[bad_pos]);
641 }
642 
643 static int mtk_nfc_format_subpage(struct mtd_info *mtd, u32 offset,
644 				  u32 len, const u8 *buf)
645 {
646 	struct nand_chip *chip = mtd_to_nand(mtd);
647 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
648 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
649 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
650 	u32 start, end;
651 	int i, ret;
652 
653 	start = offset / chip->ecc.size;
654 	end = DIV_ROUND_UP(offset + len, chip->ecc.size);
655 
656 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
657 	for (i = 0; i < chip->ecc.steps; i++) {
658 		memcpy(mtk_data_ptr(chip, i), data_ptr(chip, buf, i),
659 		       chip->ecc.size);
660 
661 		if (start > i || i >= end)
662 			continue;
663 
664 		if (i == mtk_nand->bad_mark.sec)
665 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
666 
667 		memcpy(mtk_oob_ptr(chip, i), oob_ptr(chip, i), fdm->reg_size);
668 
669 		/* program the CRC back to the OOB */
670 		ret = mtk_nfc_sector_encode(chip, mtk_data_ptr(chip, i));
671 		if (ret < 0)
672 			return ret;
673 	}
674 
675 	return 0;
676 }
677 
678 static void mtk_nfc_format_page(struct mtd_info *mtd, const u8 *buf)
679 {
680 	struct nand_chip *chip = mtd_to_nand(mtd);
681 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
682 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
683 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
684 	u32 i;
685 
686 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
687 	for (i = 0; i < chip->ecc.steps; i++) {
688 		if (buf)
689 			memcpy(mtk_data_ptr(chip, i), data_ptr(chip, buf, i),
690 			       chip->ecc.size);
691 
692 		if (i == mtk_nand->bad_mark.sec)
693 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
694 
695 		memcpy(mtk_oob_ptr(chip, i), oob_ptr(chip, i), fdm->reg_size);
696 	}
697 }
698 
699 static inline void mtk_nfc_read_fdm(struct nand_chip *chip, u32 start,
700 				    u32 sectors)
701 {
702 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
703 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
704 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
705 	u32 vall, valm;
706 	u8 *oobptr;
707 	int i, j;
708 
709 	for (i = 0; i < sectors; i++) {
710 		oobptr = oob_ptr(chip, start + i);
711 		vall = nfi_readl(nfc, NFI_FDML(i));
712 		valm = nfi_readl(nfc, NFI_FDMM(i));
713 
714 		for (j = 0; j < fdm->reg_size; j++)
715 			oobptr[j] = (j >= 4 ? valm : vall) >> ((j % 4) * 8);
716 	}
717 }
718 
719 static inline void mtk_nfc_write_fdm(struct nand_chip *chip)
720 {
721 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
722 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
723 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
724 	u32 vall, valm;
725 	u8 *oobptr;
726 	int i, j;
727 
728 	for (i = 0; i < chip->ecc.steps; i++) {
729 		oobptr = oob_ptr(chip, i);
730 		vall = 0;
731 		valm = 0;
732 		for (j = 0; j < 8; j++) {
733 			if (j < 4)
734 				vall |= (j < fdm->reg_size ? oobptr[j] : 0xff)
735 						<< (j * 8);
736 			else
737 				valm |= (j < fdm->reg_size ? oobptr[j] : 0xff)
738 						<< ((j - 4) * 8);
739 		}
740 		nfi_writel(nfc, vall, NFI_FDML(i));
741 		nfi_writel(nfc, valm, NFI_FDMM(i));
742 	}
743 }
744 
745 static int mtk_nfc_do_write_page(struct mtd_info *mtd, struct nand_chip *chip,
746 				 const u8 *buf, int page, int len)
747 {
748 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
749 	struct device *dev = nfc->dev;
750 	dma_addr_t addr;
751 	u32 reg;
752 	int ret;
753 
754 	addr = dma_map_single(dev, (void *)buf, len, DMA_TO_DEVICE);
755 	ret = dma_mapping_error(nfc->dev, addr);
756 	if (ret) {
757 		dev_err(nfc->dev, "dma mapping error\n");
758 		return -EINVAL;
759 	}
760 
761 	reg = nfi_readw(nfc, NFI_CNFG) | CNFG_AHB | CNFG_DMA_BURST_EN;
762 	nfi_writew(nfc, reg, NFI_CNFG);
763 
764 	nfi_writel(nfc, chip->ecc.steps << CON_SEC_SHIFT, NFI_CON);
765 	nfi_writel(nfc, lower_32_bits(addr), NFI_STRADDR);
766 	nfi_writew(nfc, INTR_AHB_DONE_EN, NFI_INTR_EN);
767 
768 	init_completion(&nfc->done);
769 
770 	reg = nfi_readl(nfc, NFI_CON) | CON_BWR;
771 	nfi_writel(nfc, reg, NFI_CON);
772 	nfi_writew(nfc, STAR_EN, NFI_STRDATA);
773 
774 	ret = wait_for_completion_timeout(&nfc->done, msecs_to_jiffies(500));
775 	if (!ret) {
776 		dev_err(dev, "program ahb done timeout\n");
777 		nfi_writew(nfc, 0, NFI_INTR_EN);
778 		ret = -ETIMEDOUT;
779 		goto timeout;
780 	}
781 
782 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_ADDRCNTR, reg,
783 					ADDRCNTR_SEC(reg) >= chip->ecc.steps,
784 					10, MTK_TIMEOUT);
785 	if (ret)
786 		dev_err(dev, "hwecc write timeout\n");
787 
788 timeout:
789 
790 	dma_unmap_single(nfc->dev, addr, len, DMA_TO_DEVICE);
791 	nfi_writel(nfc, 0, NFI_CON);
792 
793 	return ret;
794 }
795 
796 static int mtk_nfc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
797 			      const u8 *buf, int page, int raw)
798 {
799 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
800 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
801 	size_t len;
802 	const u8 *bufpoi;
803 	u32 reg;
804 	int ret;
805 
806 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
807 
808 	if (!raw) {
809 		/* OOB => FDM: from register,  ECC: from HW */
810 		reg = nfi_readw(nfc, NFI_CNFG) | CNFG_AUTO_FMT_EN;
811 		nfi_writew(nfc, reg | CNFG_HW_ECC_EN, NFI_CNFG);
812 
813 		nfc->ecc_cfg.op = ECC_ENCODE;
814 		nfc->ecc_cfg.mode = ECC_NFI_MODE;
815 		ret = mtk_ecc_enable(nfc->ecc, &nfc->ecc_cfg);
816 		if (ret) {
817 			/* clear NFI config */
818 			reg = nfi_readw(nfc, NFI_CNFG);
819 			reg &= ~(CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
820 			nfi_writew(nfc, reg, NFI_CNFG);
821 
822 			return ret;
823 		}
824 
825 		memcpy(nfc->buffer, buf, mtd->writesize);
826 		mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, raw);
827 		bufpoi = nfc->buffer;
828 
829 		/* write OOB into the FDM registers (OOB area in MTK NAND) */
830 		mtk_nfc_write_fdm(chip);
831 	} else {
832 		bufpoi = buf;
833 	}
834 
835 	len = mtd->writesize + (raw ? mtd->oobsize : 0);
836 	ret = mtk_nfc_do_write_page(mtd, chip, bufpoi, page, len);
837 
838 	if (!raw)
839 		mtk_ecc_disable(nfc->ecc);
840 
841 	if (ret)
842 		return ret;
843 
844 	return nand_prog_page_end_op(chip);
845 }
846 
847 static int mtk_nfc_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
848 				    int oob_on, int page)
849 {
850 	return mtk_nfc_write_page(nand_to_mtd(chip), chip, buf, page, 0);
851 }
852 
853 static int mtk_nfc_write_page_raw(struct nand_chip *chip, const u8 *buf,
854 				  int oob_on, int pg)
855 {
856 	struct mtd_info *mtd = nand_to_mtd(chip);
857 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
858 
859 	mtk_nfc_format_page(mtd, buf);
860 	return mtk_nfc_write_page(mtd, chip, nfc->buffer, pg, 1);
861 }
862 
863 static int mtk_nfc_write_subpage_hwecc(struct nand_chip *chip, u32 offset,
864 				       u32 data_len, const u8 *buf,
865 				       int oob_on, int page)
866 {
867 	struct mtd_info *mtd = nand_to_mtd(chip);
868 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
869 	int ret;
870 
871 	ret = mtk_nfc_format_subpage(mtd, offset, data_len, buf);
872 	if (ret < 0)
873 		return ret;
874 
875 	/* use the data in the private buffer (now with FDM and CRC) */
876 	return mtk_nfc_write_page(mtd, chip, nfc->buffer, page, 1);
877 }
878 
879 static int mtk_nfc_write_oob_std(struct nand_chip *chip, int page)
880 {
881 	return mtk_nfc_write_page_raw(chip, NULL, 1, page);
882 }
883 
884 static int mtk_nfc_update_ecc_stats(struct mtd_info *mtd, u8 *buf, u32 start,
885 				    u32 sectors)
886 {
887 	struct nand_chip *chip = mtd_to_nand(mtd);
888 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
889 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
890 	struct mtk_ecc_stats stats;
891 	u32 reg_size = mtk_nand->fdm.reg_size;
892 	int rc, i;
893 
894 	rc = nfi_readl(nfc, NFI_STA) & STA_EMP_PAGE;
895 	if (rc) {
896 		memset(buf, 0xff, sectors * chip->ecc.size);
897 		for (i = 0; i < sectors; i++)
898 			memset(oob_ptr(chip, start + i), 0xff, reg_size);
899 		return 0;
900 	}
901 
902 	mtk_ecc_get_stats(nfc->ecc, &stats, sectors);
903 	mtd->ecc_stats.corrected += stats.corrected;
904 	mtd->ecc_stats.failed += stats.failed;
905 
906 	return stats.bitflips;
907 }
908 
909 static int mtk_nfc_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
910 				u32 data_offs, u32 readlen,
911 				u8 *bufpoi, int page, int raw)
912 {
913 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
914 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
915 	u32 spare = mtk_nand->spare_per_sector;
916 	u32 column, sectors, start, end, reg;
917 	dma_addr_t addr;
918 	int bitflips = 0;
919 	size_t len;
920 	u8 *buf;
921 	int rc;
922 
923 	start = data_offs / chip->ecc.size;
924 	end = DIV_ROUND_UP(data_offs + readlen, chip->ecc.size);
925 
926 	sectors = end - start;
927 	column = start * (chip->ecc.size + spare);
928 
929 	len = sectors * chip->ecc.size + (raw ? sectors * spare : 0);
930 	buf = bufpoi + start * chip->ecc.size;
931 
932 	nand_read_page_op(chip, page, column, NULL, 0);
933 
934 	addr = dma_map_single(nfc->dev, buf, len, DMA_FROM_DEVICE);
935 	rc = dma_mapping_error(nfc->dev, addr);
936 	if (rc) {
937 		dev_err(nfc->dev, "dma mapping error\n");
938 
939 		return -EINVAL;
940 	}
941 
942 	reg = nfi_readw(nfc, NFI_CNFG);
943 	reg |= CNFG_READ_EN | CNFG_DMA_BURST_EN | CNFG_AHB;
944 	if (!raw) {
945 		reg |= CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN;
946 		nfi_writew(nfc, reg, NFI_CNFG);
947 
948 		nfc->ecc_cfg.mode = ECC_NFI_MODE;
949 		nfc->ecc_cfg.sectors = sectors;
950 		nfc->ecc_cfg.op = ECC_DECODE;
951 		rc = mtk_ecc_enable(nfc->ecc, &nfc->ecc_cfg);
952 		if (rc) {
953 			dev_err(nfc->dev, "ecc enable\n");
954 			/* clear NFI_CNFG */
955 			reg &= ~(CNFG_DMA_BURST_EN | CNFG_AHB | CNFG_READ_EN |
956 				CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
957 			nfi_writew(nfc, reg, NFI_CNFG);
958 			dma_unmap_single(nfc->dev, addr, len, DMA_FROM_DEVICE);
959 
960 			return rc;
961 		}
962 	} else {
963 		nfi_writew(nfc, reg, NFI_CNFG);
964 	}
965 
966 	nfi_writel(nfc, sectors << CON_SEC_SHIFT, NFI_CON);
967 	nfi_writew(nfc, INTR_AHB_DONE_EN, NFI_INTR_EN);
968 	nfi_writel(nfc, lower_32_bits(addr), NFI_STRADDR);
969 
970 	init_completion(&nfc->done);
971 	reg = nfi_readl(nfc, NFI_CON) | CON_BRD;
972 	nfi_writel(nfc, reg, NFI_CON);
973 	nfi_writew(nfc, STAR_EN, NFI_STRDATA);
974 
975 	rc = wait_for_completion_timeout(&nfc->done, msecs_to_jiffies(500));
976 	if (!rc)
977 		dev_warn(nfc->dev, "read ahb/dma done timeout\n");
978 
979 	rc = readl_poll_timeout_atomic(nfc->regs + NFI_BYTELEN, reg,
980 				       ADDRCNTR_SEC(reg) >= sectors, 10,
981 				       MTK_TIMEOUT);
982 	if (rc < 0) {
983 		dev_err(nfc->dev, "subpage done timeout\n");
984 		bitflips = -EIO;
985 	} else if (!raw) {
986 		rc = mtk_ecc_wait_done(nfc->ecc, ECC_DECODE);
987 		bitflips = rc < 0 ? -ETIMEDOUT :
988 			mtk_nfc_update_ecc_stats(mtd, buf, start, sectors);
989 		mtk_nfc_read_fdm(chip, start, sectors);
990 	}
991 
992 	dma_unmap_single(nfc->dev, addr, len, DMA_FROM_DEVICE);
993 
994 	if (raw)
995 		goto done;
996 
997 	mtk_ecc_disable(nfc->ecc);
998 
999 	if (clamp(mtk_nand->bad_mark.sec, start, end) == mtk_nand->bad_mark.sec)
1000 		mtk_nand->bad_mark.bm_swap(mtd, bufpoi, raw);
1001 done:
1002 	nfi_writel(nfc, 0, NFI_CON);
1003 
1004 	return bitflips;
1005 }
1006 
1007 static int mtk_nfc_read_subpage_hwecc(struct nand_chip *chip, u32 off,
1008 				      u32 len, u8 *p, int pg)
1009 {
1010 	return mtk_nfc_read_subpage(nand_to_mtd(chip), chip, off, len, p, pg,
1011 				    0);
1012 }
1013 
1014 static int mtk_nfc_read_page_hwecc(struct nand_chip *chip, u8 *p, int oob_on,
1015 				   int pg)
1016 {
1017 	struct mtd_info *mtd = nand_to_mtd(chip);
1018 
1019 	return mtk_nfc_read_subpage(mtd, chip, 0, mtd->writesize, p, pg, 0);
1020 }
1021 
1022 static int mtk_nfc_read_page_raw(struct nand_chip *chip, u8 *buf, int oob_on,
1023 				 int page)
1024 {
1025 	struct mtd_info *mtd = nand_to_mtd(chip);
1026 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1027 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
1028 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
1029 	int i, ret;
1030 
1031 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
1032 	ret = mtk_nfc_read_subpage(mtd, chip, 0, mtd->writesize, nfc->buffer,
1033 				   page, 1);
1034 	if (ret < 0)
1035 		return ret;
1036 
1037 	for (i = 0; i < chip->ecc.steps; i++) {
1038 		memcpy(oob_ptr(chip, i), mtk_oob_ptr(chip, i), fdm->reg_size);
1039 
1040 		if (i == mtk_nand->bad_mark.sec)
1041 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
1042 
1043 		if (buf)
1044 			memcpy(data_ptr(chip, buf, i), mtk_data_ptr(chip, i),
1045 			       chip->ecc.size);
1046 	}
1047 
1048 	return ret;
1049 }
1050 
1051 static int mtk_nfc_read_oob_std(struct nand_chip *chip, int page)
1052 {
1053 	return mtk_nfc_read_page_raw(chip, NULL, 1, page);
1054 }
1055 
1056 static inline void mtk_nfc_hw_init(struct mtk_nfc *nfc)
1057 {
1058 	/*
1059 	 * CNRNB: nand ready/busy register
1060 	 * -------------------------------
1061 	 * 7:4: timeout register for polling the NAND busy/ready signal
1062 	 * 0  : poll the status of the busy/ready signal after [7:4]*16 cycles.
1063 	 */
1064 	nfi_writew(nfc, 0xf1, NFI_CNRNB);
1065 	nfi_writel(nfc, PAGEFMT_8K_16K, NFI_PAGEFMT);
1066 
1067 	mtk_nfc_hw_reset(nfc);
1068 
1069 	nfi_readl(nfc, NFI_INTR_STA);
1070 	nfi_writel(nfc, 0, NFI_INTR_EN);
1071 }
1072 
1073 static irqreturn_t mtk_nfc_irq(int irq, void *id)
1074 {
1075 	struct mtk_nfc *nfc = id;
1076 	u16 sta, ien;
1077 
1078 	sta = nfi_readw(nfc, NFI_INTR_STA);
1079 	ien = nfi_readw(nfc, NFI_INTR_EN);
1080 
1081 	if (!(sta & ien))
1082 		return IRQ_NONE;
1083 
1084 	nfi_writew(nfc, ~sta & ien, NFI_INTR_EN);
1085 	complete(&nfc->done);
1086 
1087 	return IRQ_HANDLED;
1088 }
1089 
1090 static int mtk_nfc_enable_clk(struct device *dev, struct mtk_nfc_clk *clk)
1091 {
1092 	int ret;
1093 
1094 	ret = clk_prepare_enable(clk->nfi_clk);
1095 	if (ret) {
1096 		dev_err(dev, "failed to enable nfi clk\n");
1097 		return ret;
1098 	}
1099 
1100 	ret = clk_prepare_enable(clk->pad_clk);
1101 	if (ret) {
1102 		dev_err(dev, "failed to enable pad clk\n");
1103 		clk_disable_unprepare(clk->nfi_clk);
1104 		return ret;
1105 	}
1106 
1107 	return 0;
1108 }
1109 
1110 static void mtk_nfc_disable_clk(struct mtk_nfc_clk *clk)
1111 {
1112 	clk_disable_unprepare(clk->nfi_clk);
1113 	clk_disable_unprepare(clk->pad_clk);
1114 }
1115 
1116 static int mtk_nfc_ooblayout_free(struct mtd_info *mtd, int section,
1117 				  struct mtd_oob_region *oob_region)
1118 {
1119 	struct nand_chip *chip = mtd_to_nand(mtd);
1120 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1121 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
1122 	u32 eccsteps;
1123 
1124 	eccsteps = mtd->writesize / chip->ecc.size;
1125 
1126 	if (section >= eccsteps)
1127 		return -ERANGE;
1128 
1129 	oob_region->length = fdm->reg_size - fdm->ecc_size;
1130 	oob_region->offset = section * fdm->reg_size + fdm->ecc_size;
1131 
1132 	return 0;
1133 }
1134 
1135 static int mtk_nfc_ooblayout_ecc(struct mtd_info *mtd, int section,
1136 				 struct mtd_oob_region *oob_region)
1137 {
1138 	struct nand_chip *chip = mtd_to_nand(mtd);
1139 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1140 	u32 eccsteps;
1141 
1142 	if (section)
1143 		return -ERANGE;
1144 
1145 	eccsteps = mtd->writesize / chip->ecc.size;
1146 	oob_region->offset = mtk_nand->fdm.reg_size * eccsteps;
1147 	oob_region->length = mtd->oobsize - oob_region->offset;
1148 
1149 	return 0;
1150 }
1151 
1152 static const struct mtd_ooblayout_ops mtk_nfc_ooblayout_ops = {
1153 	.free = mtk_nfc_ooblayout_free,
1154 	.ecc = mtk_nfc_ooblayout_ecc,
1155 };
1156 
1157 static void mtk_nfc_set_fdm(struct mtk_nfc_fdm *fdm, struct mtd_info *mtd)
1158 {
1159 	struct nand_chip *nand = mtd_to_nand(mtd);
1160 	struct mtk_nfc_nand_chip *chip = to_mtk_nand(nand);
1161 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1162 	u32 ecc_bytes;
1163 
1164 	ecc_bytes = DIV_ROUND_UP(nand->ecc.strength *
1165 				 mtk_ecc_get_parity_bits(nfc->ecc), 8);
1166 
1167 	fdm->reg_size = chip->spare_per_sector - ecc_bytes;
1168 	if (fdm->reg_size > NFI_FDM_MAX_SIZE)
1169 		fdm->reg_size = NFI_FDM_MAX_SIZE;
1170 
1171 	/* bad block mark storage */
1172 	fdm->ecc_size = 1;
1173 }
1174 
1175 static void mtk_nfc_set_bad_mark_ctl(struct mtk_nfc_bad_mark_ctl *bm_ctl,
1176 				     struct mtd_info *mtd)
1177 {
1178 	struct nand_chip *nand = mtd_to_nand(mtd);
1179 
1180 	if (mtd->writesize == 512) {
1181 		bm_ctl->bm_swap = mtk_nfc_no_bad_mark_swap;
1182 	} else {
1183 		bm_ctl->bm_swap = mtk_nfc_bad_mark_swap;
1184 		bm_ctl->sec = mtd->writesize / mtk_data_len(nand);
1185 		bm_ctl->pos = mtd->writesize % mtk_data_len(nand);
1186 	}
1187 }
1188 
1189 static int mtk_nfc_set_spare_per_sector(u32 *sps, struct mtd_info *mtd)
1190 {
1191 	struct nand_chip *nand = mtd_to_nand(mtd);
1192 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1193 	const u8 *spare = nfc->caps->spare_size;
1194 	u32 eccsteps, i, closest_spare = 0;
1195 
1196 	eccsteps = mtd->writesize / nand->ecc.size;
1197 	*sps = mtd->oobsize / eccsteps;
1198 
1199 	if (nand->ecc.size == 1024)
1200 		*sps >>= 1;
1201 
1202 	if (*sps < MTK_NFC_MIN_SPARE)
1203 		return -EINVAL;
1204 
1205 	for (i = 0; i < nfc->caps->num_spare_size; i++) {
1206 		if (*sps >= spare[i] && spare[i] >= spare[closest_spare]) {
1207 			closest_spare = i;
1208 			if (*sps == spare[i])
1209 				break;
1210 		}
1211 	}
1212 
1213 	*sps = spare[closest_spare];
1214 
1215 	if (nand->ecc.size == 1024)
1216 		*sps <<= 1;
1217 
1218 	return 0;
1219 }
1220 
1221 static int mtk_nfc_ecc_init(struct device *dev, struct mtd_info *mtd)
1222 {
1223 	struct nand_chip *nand = mtd_to_nand(mtd);
1224 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1225 	u32 spare;
1226 	int free, ret;
1227 
1228 	/* support only ecc hw mode */
1229 	if (nand->ecc.mode != NAND_ECC_HW) {
1230 		dev_err(dev, "ecc.mode not supported\n");
1231 		return -EINVAL;
1232 	}
1233 
1234 	/* if optional dt settings not present */
1235 	if (!nand->ecc.size || !nand->ecc.strength) {
1236 		/* use datasheet requirements */
1237 		nand->ecc.strength = nand->base.eccreq.strength;
1238 		nand->ecc.size = nand->base.eccreq.step_size;
1239 
1240 		/*
1241 		 * align eccstrength and eccsize
1242 		 * this controller only supports 512 and 1024 sizes
1243 		 */
1244 		if (nand->ecc.size < 1024) {
1245 			if (mtd->writesize > 512 &&
1246 			    nfc->caps->max_sector_size > 512) {
1247 				nand->ecc.size = 1024;
1248 				nand->ecc.strength <<= 1;
1249 			} else {
1250 				nand->ecc.size = 512;
1251 			}
1252 		} else {
1253 			nand->ecc.size = 1024;
1254 		}
1255 
1256 		ret = mtk_nfc_set_spare_per_sector(&spare, mtd);
1257 		if (ret)
1258 			return ret;
1259 
1260 		/* calculate oob bytes except ecc parity data */
1261 		free = (nand->ecc.strength * mtk_ecc_get_parity_bits(nfc->ecc)
1262 			+ 7) >> 3;
1263 		free = spare - free;
1264 
1265 		/*
1266 		 * enhance ecc strength if oob left is bigger than max FDM size
1267 		 * or reduce ecc strength if oob size is not enough for ecc
1268 		 * parity data.
1269 		 */
1270 		if (free > NFI_FDM_MAX_SIZE) {
1271 			spare -= NFI_FDM_MAX_SIZE;
1272 			nand->ecc.strength = (spare << 3) /
1273 					     mtk_ecc_get_parity_bits(nfc->ecc);
1274 		} else if (free < 0) {
1275 			spare -= NFI_FDM_MIN_SIZE;
1276 			nand->ecc.strength = (spare << 3) /
1277 					     mtk_ecc_get_parity_bits(nfc->ecc);
1278 		}
1279 	}
1280 
1281 	mtk_ecc_adjust_strength(nfc->ecc, &nand->ecc.strength);
1282 
1283 	dev_info(dev, "eccsize %d eccstrength %d\n",
1284 		 nand->ecc.size, nand->ecc.strength);
1285 
1286 	return 0;
1287 }
1288 
1289 static int mtk_nfc_attach_chip(struct nand_chip *chip)
1290 {
1291 	struct mtd_info *mtd = nand_to_mtd(chip);
1292 	struct device *dev = mtd->dev.parent;
1293 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
1294 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1295 	int len;
1296 	int ret;
1297 
1298 	if (chip->options & NAND_BUSWIDTH_16) {
1299 		dev_err(dev, "16bits buswidth not supported");
1300 		return -EINVAL;
1301 	}
1302 
1303 	/* store bbt magic in page, cause OOB is not protected */
1304 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1305 		chip->bbt_options |= NAND_BBT_NO_OOB;
1306 
1307 	ret = mtk_nfc_ecc_init(dev, mtd);
1308 	if (ret)
1309 		return ret;
1310 
1311 	ret = mtk_nfc_set_spare_per_sector(&mtk_nand->spare_per_sector, mtd);
1312 	if (ret)
1313 		return ret;
1314 
1315 	mtk_nfc_set_fdm(&mtk_nand->fdm, mtd);
1316 	mtk_nfc_set_bad_mark_ctl(&mtk_nand->bad_mark, mtd);
1317 
1318 	len = mtd->writesize + mtd->oobsize;
1319 	nfc->buffer = devm_kzalloc(dev, len, GFP_KERNEL);
1320 	if (!nfc->buffer)
1321 		return  -ENOMEM;
1322 
1323 	return 0;
1324 }
1325 
1326 static const struct nand_controller_ops mtk_nfc_controller_ops = {
1327 	.attach_chip = mtk_nfc_attach_chip,
1328 	.setup_data_interface = mtk_nfc_setup_data_interface,
1329 };
1330 
1331 static int mtk_nfc_nand_chip_init(struct device *dev, struct mtk_nfc *nfc,
1332 				  struct device_node *np)
1333 {
1334 	struct mtk_nfc_nand_chip *chip;
1335 	struct nand_chip *nand;
1336 	struct mtd_info *mtd;
1337 	int nsels;
1338 	u32 tmp;
1339 	int ret;
1340 	int i;
1341 
1342 	if (!of_get_property(np, "reg", &nsels))
1343 		return -ENODEV;
1344 
1345 	nsels /= sizeof(u32);
1346 	if (!nsels || nsels > MTK_NAND_MAX_NSELS) {
1347 		dev_err(dev, "invalid reg property size %d\n", nsels);
1348 		return -EINVAL;
1349 	}
1350 
1351 	chip = devm_kzalloc(dev, sizeof(*chip) + nsels * sizeof(u8),
1352 			    GFP_KERNEL);
1353 	if (!chip)
1354 		return -ENOMEM;
1355 
1356 	chip->nsels = nsels;
1357 	for (i = 0; i < nsels; i++) {
1358 		ret = of_property_read_u32_index(np, "reg", i, &tmp);
1359 		if (ret) {
1360 			dev_err(dev, "reg property failure : %d\n", ret);
1361 			return ret;
1362 		}
1363 
1364 		if (tmp >= MTK_NAND_MAX_NSELS) {
1365 			dev_err(dev, "invalid CS: %u\n", tmp);
1366 			return -EINVAL;
1367 		}
1368 
1369 		if (test_and_set_bit(tmp, &nfc->assigned_cs)) {
1370 			dev_err(dev, "CS %u already assigned\n", tmp);
1371 			return -EINVAL;
1372 		}
1373 
1374 		chip->sels[i] = tmp;
1375 	}
1376 
1377 	nand = &chip->nand;
1378 	nand->controller = &nfc->controller;
1379 
1380 	nand_set_flash_node(nand, np);
1381 	nand_set_controller_data(nand, nfc);
1382 
1383 	nand->options |= NAND_USES_DMA | NAND_SUBPAGE_READ;
1384 	nand->legacy.dev_ready = mtk_nfc_dev_ready;
1385 	nand->legacy.select_chip = mtk_nfc_select_chip;
1386 	nand->legacy.write_byte = mtk_nfc_write_byte;
1387 	nand->legacy.write_buf = mtk_nfc_write_buf;
1388 	nand->legacy.read_byte = mtk_nfc_read_byte;
1389 	nand->legacy.read_buf = mtk_nfc_read_buf;
1390 	nand->legacy.cmd_ctrl = mtk_nfc_cmd_ctrl;
1391 
1392 	/* set default mode in case dt entry is missing */
1393 	nand->ecc.mode = NAND_ECC_HW;
1394 
1395 	nand->ecc.write_subpage = mtk_nfc_write_subpage_hwecc;
1396 	nand->ecc.write_page_raw = mtk_nfc_write_page_raw;
1397 	nand->ecc.write_page = mtk_nfc_write_page_hwecc;
1398 	nand->ecc.write_oob_raw = mtk_nfc_write_oob_std;
1399 	nand->ecc.write_oob = mtk_nfc_write_oob_std;
1400 
1401 	nand->ecc.read_subpage = mtk_nfc_read_subpage_hwecc;
1402 	nand->ecc.read_page_raw = mtk_nfc_read_page_raw;
1403 	nand->ecc.read_page = mtk_nfc_read_page_hwecc;
1404 	nand->ecc.read_oob_raw = mtk_nfc_read_oob_std;
1405 	nand->ecc.read_oob = mtk_nfc_read_oob_std;
1406 
1407 	mtd = nand_to_mtd(nand);
1408 	mtd->owner = THIS_MODULE;
1409 	mtd->dev.parent = dev;
1410 	mtd->name = MTK_NAME;
1411 	mtd_set_ooblayout(mtd, &mtk_nfc_ooblayout_ops);
1412 
1413 	mtk_nfc_hw_init(nfc);
1414 
1415 	ret = nand_scan(nand, nsels);
1416 	if (ret)
1417 		return ret;
1418 
1419 	ret = mtd_device_register(mtd, NULL, 0);
1420 	if (ret) {
1421 		dev_err(dev, "mtd parse partition error\n");
1422 		nand_cleanup(nand);
1423 		return ret;
1424 	}
1425 
1426 	list_add_tail(&chip->node, &nfc->chips);
1427 
1428 	return 0;
1429 }
1430 
1431 static int mtk_nfc_nand_chips_init(struct device *dev, struct mtk_nfc *nfc)
1432 {
1433 	struct device_node *np = dev->of_node;
1434 	struct device_node *nand_np;
1435 	int ret;
1436 
1437 	for_each_child_of_node(np, nand_np) {
1438 		ret = mtk_nfc_nand_chip_init(dev, nfc, nand_np);
1439 		if (ret) {
1440 			of_node_put(nand_np);
1441 			return ret;
1442 		}
1443 	}
1444 
1445 	return 0;
1446 }
1447 
1448 static const struct mtk_nfc_caps mtk_nfc_caps_mt2701 = {
1449 	.spare_size = spare_size_mt2701,
1450 	.num_spare_size = 16,
1451 	.pageformat_spare_shift = 4,
1452 	.nfi_clk_div = 1,
1453 	.max_sector = 16,
1454 	.max_sector_size = 1024,
1455 };
1456 
1457 static const struct mtk_nfc_caps mtk_nfc_caps_mt2712 = {
1458 	.spare_size = spare_size_mt2712,
1459 	.num_spare_size = 19,
1460 	.pageformat_spare_shift = 16,
1461 	.nfi_clk_div = 2,
1462 	.max_sector = 16,
1463 	.max_sector_size = 1024,
1464 };
1465 
1466 static const struct mtk_nfc_caps mtk_nfc_caps_mt7622 = {
1467 	.spare_size = spare_size_mt7622,
1468 	.num_spare_size = 4,
1469 	.pageformat_spare_shift = 4,
1470 	.nfi_clk_div = 1,
1471 	.max_sector = 8,
1472 	.max_sector_size = 512,
1473 };
1474 
1475 static const struct of_device_id mtk_nfc_id_table[] = {
1476 	{
1477 		.compatible = "mediatek,mt2701-nfc",
1478 		.data = &mtk_nfc_caps_mt2701,
1479 	}, {
1480 		.compatible = "mediatek,mt2712-nfc",
1481 		.data = &mtk_nfc_caps_mt2712,
1482 	}, {
1483 		.compatible = "mediatek,mt7622-nfc",
1484 		.data = &mtk_nfc_caps_mt7622,
1485 	},
1486 	{}
1487 };
1488 MODULE_DEVICE_TABLE(of, mtk_nfc_id_table);
1489 
1490 static int mtk_nfc_probe(struct platform_device *pdev)
1491 {
1492 	struct device *dev = &pdev->dev;
1493 	struct device_node *np = dev->of_node;
1494 	struct mtk_nfc *nfc;
1495 	struct resource *res;
1496 	int ret, irq;
1497 
1498 	nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
1499 	if (!nfc)
1500 		return -ENOMEM;
1501 
1502 	nand_controller_init(&nfc->controller);
1503 	INIT_LIST_HEAD(&nfc->chips);
1504 	nfc->controller.ops = &mtk_nfc_controller_ops;
1505 
1506 	/* probe defer if not ready */
1507 	nfc->ecc = of_mtk_ecc_get(np);
1508 	if (IS_ERR(nfc->ecc))
1509 		return PTR_ERR(nfc->ecc);
1510 	else if (!nfc->ecc)
1511 		return -ENODEV;
1512 
1513 	nfc->caps = of_device_get_match_data(dev);
1514 	nfc->dev = dev;
1515 
1516 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1517 	nfc->regs = devm_ioremap_resource(dev, res);
1518 	if (IS_ERR(nfc->regs)) {
1519 		ret = PTR_ERR(nfc->regs);
1520 		goto release_ecc;
1521 	}
1522 
1523 	nfc->clk.nfi_clk = devm_clk_get(dev, "nfi_clk");
1524 	if (IS_ERR(nfc->clk.nfi_clk)) {
1525 		dev_err(dev, "no clk\n");
1526 		ret = PTR_ERR(nfc->clk.nfi_clk);
1527 		goto release_ecc;
1528 	}
1529 
1530 	nfc->clk.pad_clk = devm_clk_get(dev, "pad_clk");
1531 	if (IS_ERR(nfc->clk.pad_clk)) {
1532 		dev_err(dev, "no pad clk\n");
1533 		ret = PTR_ERR(nfc->clk.pad_clk);
1534 		goto release_ecc;
1535 	}
1536 
1537 	ret = mtk_nfc_enable_clk(dev, &nfc->clk);
1538 	if (ret)
1539 		goto release_ecc;
1540 
1541 	irq = platform_get_irq(pdev, 0);
1542 	if (irq < 0) {
1543 		ret = -EINVAL;
1544 		goto clk_disable;
1545 	}
1546 
1547 	ret = devm_request_irq(dev, irq, mtk_nfc_irq, 0x0, "mtk-nand", nfc);
1548 	if (ret) {
1549 		dev_err(dev, "failed to request nfi irq\n");
1550 		goto clk_disable;
1551 	}
1552 
1553 	ret = dma_set_mask(dev, DMA_BIT_MASK(32));
1554 	if (ret) {
1555 		dev_err(dev, "failed to set dma mask\n");
1556 		goto clk_disable;
1557 	}
1558 
1559 	platform_set_drvdata(pdev, nfc);
1560 
1561 	ret = mtk_nfc_nand_chips_init(dev, nfc);
1562 	if (ret) {
1563 		dev_err(dev, "failed to init nand chips\n");
1564 		goto clk_disable;
1565 	}
1566 
1567 	return 0;
1568 
1569 clk_disable:
1570 	mtk_nfc_disable_clk(&nfc->clk);
1571 
1572 release_ecc:
1573 	mtk_ecc_release(nfc->ecc);
1574 
1575 	return ret;
1576 }
1577 
1578 static int mtk_nfc_remove(struct platform_device *pdev)
1579 {
1580 	struct mtk_nfc *nfc = platform_get_drvdata(pdev);
1581 	struct mtk_nfc_nand_chip *mtk_chip;
1582 	struct nand_chip *chip;
1583 	int ret;
1584 
1585 	while (!list_empty(&nfc->chips)) {
1586 		mtk_chip = list_first_entry(&nfc->chips,
1587 					    struct mtk_nfc_nand_chip, node);
1588 		chip = &mtk_chip->nand;
1589 		ret = mtd_device_unregister(nand_to_mtd(chip));
1590 		WARN_ON(ret);
1591 		nand_cleanup(chip);
1592 		list_del(&mtk_chip->node);
1593 	}
1594 
1595 	mtk_ecc_release(nfc->ecc);
1596 	mtk_nfc_disable_clk(&nfc->clk);
1597 
1598 	return 0;
1599 }
1600 
1601 #ifdef CONFIG_PM_SLEEP
1602 static int mtk_nfc_suspend(struct device *dev)
1603 {
1604 	struct mtk_nfc *nfc = dev_get_drvdata(dev);
1605 
1606 	mtk_nfc_disable_clk(&nfc->clk);
1607 
1608 	return 0;
1609 }
1610 
1611 static int mtk_nfc_resume(struct device *dev)
1612 {
1613 	struct mtk_nfc *nfc = dev_get_drvdata(dev);
1614 	struct mtk_nfc_nand_chip *chip;
1615 	struct nand_chip *nand;
1616 	int ret;
1617 	u32 i;
1618 
1619 	udelay(200);
1620 
1621 	ret = mtk_nfc_enable_clk(dev, &nfc->clk);
1622 	if (ret)
1623 		return ret;
1624 
1625 	/* reset NAND chip if VCC was powered off */
1626 	list_for_each_entry(chip, &nfc->chips, node) {
1627 		nand = &chip->nand;
1628 		for (i = 0; i < chip->nsels; i++)
1629 			nand_reset(nand, i);
1630 	}
1631 
1632 	return 0;
1633 }
1634 
1635 static SIMPLE_DEV_PM_OPS(mtk_nfc_pm_ops, mtk_nfc_suspend, mtk_nfc_resume);
1636 #endif
1637 
1638 static struct platform_driver mtk_nfc_driver = {
1639 	.probe  = mtk_nfc_probe,
1640 	.remove = mtk_nfc_remove,
1641 	.driver = {
1642 		.name  = MTK_NAME,
1643 		.of_match_table = mtk_nfc_id_table,
1644 #ifdef CONFIG_PM_SLEEP
1645 		.pm = &mtk_nfc_pm_ops,
1646 #endif
1647 	},
1648 };
1649 
1650 module_platform_driver(mtk_nfc_driver);
1651 
1652 MODULE_LICENSE("Dual MIT/GPL");
1653 MODULE_AUTHOR("Xiaolei Li <xiaolei.li@mediatek.com>");
1654 MODULE_DESCRIPTION("MTK Nand Flash Controller Driver");
1655