xref: /openbmc/linux/drivers/mtd/nand/raw/mtk_nand.c (revision 7f1005dd)
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/mtd/nand-ecc-mtk.h>
20 
21 /* NAND controller register definition */
22 #define NFI_CNFG		(0x00)
23 #define		CNFG_AHB		BIT(0)
24 #define		CNFG_READ_EN		BIT(1)
25 #define		CNFG_DMA_BURST_EN	BIT(2)
26 #define		CNFG_BYTE_RW		BIT(6)
27 #define		CNFG_HW_ECC_EN		BIT(8)
28 #define		CNFG_AUTO_FMT_EN	BIT(9)
29 #define		CNFG_OP_CUST		(6 << 12)
30 #define NFI_PAGEFMT		(0x04)
31 #define		PAGEFMT_FDM_ECC_SHIFT	(12)
32 #define		PAGEFMT_FDM_SHIFT	(8)
33 #define		PAGEFMT_SEC_SEL_512	BIT(2)
34 #define		PAGEFMT_512_2K		(0)
35 #define		PAGEFMT_2K_4K		(1)
36 #define		PAGEFMT_4K_8K		(2)
37 #define		PAGEFMT_8K_16K		(3)
38 /* NFI control */
39 #define NFI_CON			(0x08)
40 #define		CON_FIFO_FLUSH		BIT(0)
41 #define		CON_NFI_RST		BIT(1)
42 #define		CON_BRD			BIT(8)  /* burst  read */
43 #define		CON_BWR			BIT(9)	/* burst  write */
44 #define		CON_SEC_SHIFT		(12)
45 /* Timming control register */
46 #define NFI_ACCCON		(0x0C)
47 #define NFI_INTR_EN		(0x10)
48 #define		INTR_AHB_DONE_EN	BIT(6)
49 #define NFI_INTR_STA		(0x14)
50 #define NFI_CMD			(0x20)
51 #define NFI_ADDRNOB		(0x30)
52 #define NFI_COLADDR		(0x34)
53 #define NFI_ROWADDR		(0x38)
54 #define NFI_STRDATA		(0x40)
55 #define		STAR_EN			(1)
56 #define		STAR_DE			(0)
57 #define NFI_CNRNB		(0x44)
58 #define NFI_DATAW		(0x50)
59 #define NFI_DATAR		(0x54)
60 #define NFI_PIO_DIRDY		(0x58)
61 #define		PIO_DI_RDY		(0x01)
62 #define NFI_STA			(0x60)
63 #define		STA_CMD			BIT(0)
64 #define		STA_ADDR		BIT(1)
65 #define		STA_BUSY		BIT(8)
66 #define		STA_EMP_PAGE		BIT(12)
67 #define		NFI_FSM_CUSTDATA	(0xe << 16)
68 #define		NFI_FSM_MASK		(0xf << 16)
69 #define NFI_ADDRCNTR		(0x70)
70 #define		CNTR_MASK		GENMASK(16, 12)
71 #define		ADDRCNTR_SEC_SHIFT	(12)
72 #define		ADDRCNTR_SEC(val) \
73 		(((val) & CNTR_MASK) >> ADDRCNTR_SEC_SHIFT)
74 #define NFI_STRADDR		(0x80)
75 #define NFI_BYTELEN		(0x84)
76 #define NFI_CSEL		(0x90)
77 #define NFI_FDML(x)		(0xA0 + (x) * sizeof(u32) * 2)
78 #define NFI_FDMM(x)		(0xA4 + (x) * sizeof(u32) * 2)
79 #define NFI_FDM_MAX_SIZE	(8)
80 #define NFI_FDM_MIN_SIZE	(1)
81 #define NFI_DEBUG_CON1		(0x220)
82 #define		STROBE_MASK		GENMASK(4, 3)
83 #define		STROBE_SHIFT		(3)
84 #define		MAX_STROBE_DLY		(3)
85 #define NFI_MASTER_STA		(0x224)
86 #define		MASTER_STA_MASK		(0x0FFF)
87 #define NFI_EMPTY_THRESH	(0x23C)
88 
89 #define MTK_NAME		"mtk-nand"
90 #define KB(x)			((x) * 1024UL)
91 #define MB(x)			(KB(x) * 1024UL)
92 
93 #define MTK_TIMEOUT		(500000)
94 #define MTK_RESET_TIMEOUT	(1000000)
95 #define MTK_NAND_MAX_NSELS	(2)
96 #define MTK_NFC_MIN_SPARE	(16)
97 #define ACCTIMING(tpoecs, tprecs, tc2r, tw2r, twh, twst, trlt) \
98 	((tpoecs) << 28 | (tprecs) << 22 | (tc2r) << 16 | \
99 	(tw2r) << 12 | (twh) << 8 | (twst) << 4 | (trlt))
100 
101 struct mtk_nfc_caps {
102 	const u8 *spare_size;
103 	u8 num_spare_size;
104 	u8 pageformat_spare_shift;
105 	u8 nfi_clk_div;
106 	u8 max_sector;
107 	u32 max_sector_size;
108 };
109 
110 struct mtk_nfc_bad_mark_ctl {
111 	void (*bm_swap)(struct mtd_info *, u8 *buf, int raw);
112 	u32 sec;
113 	u32 pos;
114 };
115 
116 /*
117  * FDM: region used to store free OOB data
118  */
119 struct mtk_nfc_fdm {
120 	u32 reg_size;
121 	u32 ecc_size;
122 };
123 
124 struct mtk_nfc_nand_chip {
125 	struct list_head node;
126 	struct nand_chip nand;
127 
128 	struct mtk_nfc_bad_mark_ctl bad_mark;
129 	struct mtk_nfc_fdm fdm;
130 	u32 spare_per_sector;
131 
132 	int nsels;
133 	u8 sels[];
134 	/* nothing after this field */
135 };
136 
137 struct mtk_nfc_clk {
138 	struct clk *nfi_clk;
139 	struct clk *pad_clk;
140 };
141 
142 struct mtk_nfc {
143 	struct nand_controller controller;
144 	struct mtk_ecc_config ecc_cfg;
145 	struct mtk_nfc_clk clk;
146 	struct mtk_ecc *ecc;
147 
148 	struct device *dev;
149 	const struct mtk_nfc_caps *caps;
150 	void __iomem *regs;
151 
152 	struct completion done;
153 	struct list_head chips;
154 
155 	u8 *buffer;
156 
157 	unsigned long assigned_cs;
158 };
159 
160 /*
161  * supported spare size of each IP.
162  * order should be the same with the spare size bitfiled defination of
163  * register NFI_PAGEFMT.
164  */
165 static const u8 spare_size_mt2701[] = {
166 	16, 26, 27, 28, 32, 36, 40, 44,	48, 49, 50, 51, 52, 62, 63, 64
167 };
168 
169 static const u8 spare_size_mt2712[] = {
170 	16, 26, 27, 28, 32, 36, 40, 44, 48, 49, 50, 51, 52, 62, 61, 63, 64, 67,
171 	74
172 };
173 
174 static const u8 spare_size_mt7622[] = {
175 	16, 26, 27, 28
176 };
177 
178 static inline struct mtk_nfc_nand_chip *to_mtk_nand(struct nand_chip *nand)
179 {
180 	return container_of(nand, struct mtk_nfc_nand_chip, nand);
181 }
182 
183 static inline u8 *data_ptr(struct nand_chip *chip, const u8 *p, int i)
184 {
185 	return (u8 *)p + i * chip->ecc.size;
186 }
187 
188 static inline u8 *oob_ptr(struct nand_chip *chip, int i)
189 {
190 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
191 	u8 *poi;
192 
193 	/* map the sector's FDM data to free oob:
194 	 * the beginning of the oob area stores the FDM data of bad mark sectors
195 	 */
196 
197 	if (i < mtk_nand->bad_mark.sec)
198 		poi = chip->oob_poi + (i + 1) * mtk_nand->fdm.reg_size;
199 	else if (i == mtk_nand->bad_mark.sec)
200 		poi = chip->oob_poi;
201 	else
202 		poi = chip->oob_poi + i * mtk_nand->fdm.reg_size;
203 
204 	return poi;
205 }
206 
207 static inline int mtk_data_len(struct nand_chip *chip)
208 {
209 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
210 
211 	return chip->ecc.size + mtk_nand->spare_per_sector;
212 }
213 
214 static inline u8 *mtk_data_ptr(struct nand_chip *chip,  int i)
215 {
216 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
217 
218 	return nfc->buffer + i * mtk_data_len(chip);
219 }
220 
221 static inline u8 *mtk_oob_ptr(struct nand_chip *chip, int i)
222 {
223 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
224 
225 	return nfc->buffer + i * mtk_data_len(chip) + chip->ecc.size;
226 }
227 
228 static inline void nfi_writel(struct mtk_nfc *nfc, u32 val, u32 reg)
229 {
230 	writel(val, nfc->regs + reg);
231 }
232 
233 static inline void nfi_writew(struct mtk_nfc *nfc, u16 val, u32 reg)
234 {
235 	writew(val, nfc->regs + reg);
236 }
237 
238 static inline void nfi_writeb(struct mtk_nfc *nfc, u8 val, u32 reg)
239 {
240 	writeb(val, nfc->regs + reg);
241 }
242 
243 static inline u32 nfi_readl(struct mtk_nfc *nfc, u32 reg)
244 {
245 	return readl_relaxed(nfc->regs + reg);
246 }
247 
248 static inline u16 nfi_readw(struct mtk_nfc *nfc, u32 reg)
249 {
250 	return readw_relaxed(nfc->regs + reg);
251 }
252 
253 static inline u8 nfi_readb(struct mtk_nfc *nfc, u32 reg)
254 {
255 	return readb_relaxed(nfc->regs + reg);
256 }
257 
258 static void mtk_nfc_hw_reset(struct mtk_nfc *nfc)
259 {
260 	struct device *dev = nfc->dev;
261 	u32 val;
262 	int ret;
263 
264 	/* reset all registers and force the NFI master to terminate */
265 	nfi_writel(nfc, CON_FIFO_FLUSH | CON_NFI_RST, NFI_CON);
266 
267 	/* wait for the master to finish the last transaction */
268 	ret = readl_poll_timeout(nfc->regs + NFI_MASTER_STA, val,
269 				 !(val & MASTER_STA_MASK), 50,
270 				 MTK_RESET_TIMEOUT);
271 	if (ret)
272 		dev_warn(dev, "master active in reset [0x%x] = 0x%x\n",
273 			 NFI_MASTER_STA, val);
274 
275 	/* ensure any status register affected by the NFI master is reset */
276 	nfi_writel(nfc, CON_FIFO_FLUSH | CON_NFI_RST, NFI_CON);
277 	nfi_writew(nfc, STAR_DE, NFI_STRDATA);
278 }
279 
280 static int mtk_nfc_send_command(struct mtk_nfc *nfc, u8 command)
281 {
282 	struct device *dev = nfc->dev;
283 	u32 val;
284 	int ret;
285 
286 	nfi_writel(nfc, command, NFI_CMD);
287 
288 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_STA, val,
289 					!(val & STA_CMD), 10,  MTK_TIMEOUT);
290 	if (ret) {
291 		dev_warn(dev, "nfi core timed out entering command mode\n");
292 		return -EIO;
293 	}
294 
295 	return 0;
296 }
297 
298 static int mtk_nfc_send_address(struct mtk_nfc *nfc, int addr)
299 {
300 	struct device *dev = nfc->dev;
301 	u32 val;
302 	int ret;
303 
304 	nfi_writel(nfc, addr, NFI_COLADDR);
305 	nfi_writel(nfc, 0, NFI_ROWADDR);
306 	nfi_writew(nfc, 1, NFI_ADDRNOB);
307 
308 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_STA, val,
309 					!(val & STA_ADDR), 10, MTK_TIMEOUT);
310 	if (ret) {
311 		dev_warn(dev, "nfi core timed out entering address mode\n");
312 		return -EIO;
313 	}
314 
315 	return 0;
316 }
317 
318 static int mtk_nfc_hw_runtime_config(struct mtd_info *mtd)
319 {
320 	struct nand_chip *chip = mtd_to_nand(mtd);
321 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
322 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
323 	u32 fmt, spare, i;
324 
325 	if (!mtd->writesize)
326 		return 0;
327 
328 	spare = mtk_nand->spare_per_sector;
329 
330 	switch (mtd->writesize) {
331 	case 512:
332 		fmt = PAGEFMT_512_2K | PAGEFMT_SEC_SEL_512;
333 		break;
334 	case KB(2):
335 		if (chip->ecc.size == 512)
336 			fmt = PAGEFMT_2K_4K | PAGEFMT_SEC_SEL_512;
337 		else
338 			fmt = PAGEFMT_512_2K;
339 		break;
340 	case KB(4):
341 		if (chip->ecc.size == 512)
342 			fmt = PAGEFMT_4K_8K | PAGEFMT_SEC_SEL_512;
343 		else
344 			fmt = PAGEFMT_2K_4K;
345 		break;
346 	case KB(8):
347 		if (chip->ecc.size == 512)
348 			fmt = PAGEFMT_8K_16K | PAGEFMT_SEC_SEL_512;
349 		else
350 			fmt = PAGEFMT_4K_8K;
351 		break;
352 	case KB(16):
353 		fmt = PAGEFMT_8K_16K;
354 		break;
355 	default:
356 		dev_err(nfc->dev, "invalid page len: %d\n", mtd->writesize);
357 		return -EINVAL;
358 	}
359 
360 	/*
361 	 * the hardware will double the value for this eccsize, so we need to
362 	 * halve it
363 	 */
364 	if (chip->ecc.size == 1024)
365 		spare >>= 1;
366 
367 	for (i = 0; i < nfc->caps->num_spare_size; i++) {
368 		if (nfc->caps->spare_size[i] == spare)
369 			break;
370 	}
371 
372 	if (i == nfc->caps->num_spare_size) {
373 		dev_err(nfc->dev, "invalid spare size %d\n", spare);
374 		return -EINVAL;
375 	}
376 
377 	fmt |= i << nfc->caps->pageformat_spare_shift;
378 
379 	fmt |= mtk_nand->fdm.reg_size << PAGEFMT_FDM_SHIFT;
380 	fmt |= mtk_nand->fdm.ecc_size << PAGEFMT_FDM_ECC_SHIFT;
381 	nfi_writel(nfc, fmt, NFI_PAGEFMT);
382 
383 	nfc->ecc_cfg.strength = chip->ecc.strength;
384 	nfc->ecc_cfg.len = chip->ecc.size + mtk_nand->fdm.ecc_size;
385 
386 	return 0;
387 }
388 
389 static inline void mtk_nfc_wait_ioready(struct mtk_nfc *nfc)
390 {
391 	int rc;
392 	u8 val;
393 
394 	rc = readb_poll_timeout_atomic(nfc->regs + NFI_PIO_DIRDY, val,
395 				       val & PIO_DI_RDY, 10, MTK_TIMEOUT);
396 	if (rc < 0)
397 		dev_err(nfc->dev, "data not ready\n");
398 }
399 
400 static inline u8 mtk_nfc_read_byte(struct nand_chip *chip)
401 {
402 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
403 	u32 reg;
404 
405 	/* after each byte read, the NFI_STA reg is reset by the hardware */
406 	reg = nfi_readl(nfc, NFI_STA) & NFI_FSM_MASK;
407 	if (reg != NFI_FSM_CUSTDATA) {
408 		reg = nfi_readw(nfc, NFI_CNFG);
409 		reg |= CNFG_BYTE_RW | CNFG_READ_EN;
410 		nfi_writew(nfc, reg, NFI_CNFG);
411 
412 		/*
413 		 * set to max sector to allow the HW to continue reading over
414 		 * unaligned accesses
415 		 */
416 		reg = (nfc->caps->max_sector << CON_SEC_SHIFT) | CON_BRD;
417 		nfi_writel(nfc, reg, NFI_CON);
418 
419 		/* trigger to fetch data */
420 		nfi_writew(nfc, STAR_EN, NFI_STRDATA);
421 	}
422 
423 	mtk_nfc_wait_ioready(nfc);
424 
425 	return nfi_readb(nfc, NFI_DATAR);
426 }
427 
428 static void mtk_nfc_read_buf(struct nand_chip *chip, u8 *buf, int len)
429 {
430 	int i;
431 
432 	for (i = 0; i < len; i++)
433 		buf[i] = mtk_nfc_read_byte(chip);
434 }
435 
436 static void mtk_nfc_write_byte(struct nand_chip *chip, u8 byte)
437 {
438 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
439 	u32 reg;
440 
441 	reg = nfi_readl(nfc, NFI_STA) & NFI_FSM_MASK;
442 
443 	if (reg != NFI_FSM_CUSTDATA) {
444 		reg = nfi_readw(nfc, NFI_CNFG) | CNFG_BYTE_RW;
445 		nfi_writew(nfc, reg, NFI_CNFG);
446 
447 		reg = nfc->caps->max_sector << CON_SEC_SHIFT | CON_BWR;
448 		nfi_writel(nfc, reg, NFI_CON);
449 
450 		nfi_writew(nfc, STAR_EN, NFI_STRDATA);
451 	}
452 
453 	mtk_nfc_wait_ioready(nfc);
454 	nfi_writeb(nfc, byte, NFI_DATAW);
455 }
456 
457 static void mtk_nfc_write_buf(struct nand_chip *chip, const u8 *buf, int len)
458 {
459 	int i;
460 
461 	for (i = 0; i < len; i++)
462 		mtk_nfc_write_byte(chip, buf[i]);
463 }
464 
465 static int mtk_nfc_exec_instr(struct nand_chip *chip,
466 			      const struct nand_op_instr *instr)
467 {
468 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
469 	unsigned int i;
470 	u32 status;
471 
472 	switch (instr->type) {
473 	case NAND_OP_CMD_INSTR:
474 		mtk_nfc_send_command(nfc, instr->ctx.cmd.opcode);
475 		return 0;
476 	case NAND_OP_ADDR_INSTR:
477 		for (i = 0; i < instr->ctx.addr.naddrs; i++)
478 			mtk_nfc_send_address(nfc, instr->ctx.addr.addrs[i]);
479 		return 0;
480 	case NAND_OP_DATA_IN_INSTR:
481 		mtk_nfc_read_buf(chip, instr->ctx.data.buf.in,
482 				 instr->ctx.data.len);
483 		return 0;
484 	case NAND_OP_DATA_OUT_INSTR:
485 		mtk_nfc_write_buf(chip, instr->ctx.data.buf.out,
486 				  instr->ctx.data.len);
487 		return 0;
488 	case NAND_OP_WAITRDY_INSTR:
489 		return readl_poll_timeout(nfc->regs + NFI_STA, status,
490 					  !(status & STA_BUSY), 20,
491 					  instr->ctx.waitrdy.timeout_ms * 1000);
492 	default:
493 		break;
494 	}
495 
496 	return -EINVAL;
497 }
498 
499 static void mtk_nfc_select_target(struct nand_chip *nand, unsigned int cs)
500 {
501 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
502 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(nand);
503 
504 	mtk_nfc_hw_runtime_config(nand_to_mtd(nand));
505 
506 	nfi_writel(nfc, mtk_nand->sels[cs], NFI_CSEL);
507 }
508 
509 static int mtk_nfc_exec_op(struct nand_chip *chip,
510 			   const struct nand_operation *op,
511 			   bool check_only)
512 {
513 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
514 	unsigned int i;
515 	int ret = 0;
516 
517 	if (check_only)
518 		return 0;
519 
520 	mtk_nfc_hw_reset(nfc);
521 	nfi_writew(nfc, CNFG_OP_CUST, NFI_CNFG);
522 	mtk_nfc_select_target(chip, op->cs);
523 
524 	for (i = 0; i < op->ninstrs; i++) {
525 		ret = mtk_nfc_exec_instr(chip, &op->instrs[i]);
526 		if (ret)
527 			break;
528 	}
529 
530 	return ret;
531 }
532 
533 static int mtk_nfc_setup_interface(struct nand_chip *chip, int csline,
534 				   const struct nand_interface_config *conf)
535 {
536 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
537 	const struct nand_sdr_timings *timings;
538 	u32 rate, tpoecs, tprecs, tc2r, tw2r, twh, twst = 0, trlt = 0;
539 	u32 temp, tsel = 0;
540 
541 	timings = nand_get_sdr_timings(conf);
542 	if (IS_ERR(timings))
543 		return -ENOTSUPP;
544 
545 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
546 		return 0;
547 
548 	rate = clk_get_rate(nfc->clk.nfi_clk);
549 	/* There is a frequency divider in some IPs */
550 	rate /= nfc->caps->nfi_clk_div;
551 
552 	/* turn clock rate into KHZ */
553 	rate /= 1000;
554 
555 	tpoecs = max(timings->tALH_min, timings->tCLH_min) / 1000;
556 	tpoecs = DIV_ROUND_UP(tpoecs * rate, 1000000);
557 	tpoecs &= 0xf;
558 
559 	tprecs = max(timings->tCLS_min, timings->tALS_min) / 1000;
560 	tprecs = DIV_ROUND_UP(tprecs * rate, 1000000);
561 	tprecs &= 0x3f;
562 
563 	/* sdr interface has no tCR which means CE# low to RE# low */
564 	tc2r = 0;
565 
566 	tw2r = timings->tWHR_min / 1000;
567 	tw2r = DIV_ROUND_UP(tw2r * rate, 1000000);
568 	tw2r = DIV_ROUND_UP(tw2r - 1, 2);
569 	tw2r &= 0xf;
570 
571 	twh = max(timings->tREH_min, timings->tWH_min) / 1000;
572 	twh = DIV_ROUND_UP(twh * rate, 1000000) - 1;
573 	twh &= 0xf;
574 
575 	/* Calculate real WE#/RE# hold time in nanosecond */
576 	temp = (twh + 1) * 1000000 / rate;
577 	/* nanosecond to picosecond */
578 	temp *= 1000;
579 
580 	/*
581 	 * WE# low level time should be expaned to meet WE# pulse time
582 	 * and WE# cycle time at the same time.
583 	 */
584 	if (temp < timings->tWC_min)
585 		twst = timings->tWC_min - temp;
586 	twst = max(timings->tWP_min, twst) / 1000;
587 	twst = DIV_ROUND_UP(twst * rate, 1000000) - 1;
588 	twst &= 0xf;
589 
590 	/*
591 	 * RE# low level time should be expaned to meet RE# pulse time
592 	 * and RE# cycle time at the same time.
593 	 */
594 	if (temp < timings->tRC_min)
595 		trlt = timings->tRC_min - temp;
596 	trlt = max(trlt, timings->tRP_min) / 1000;
597 	trlt = DIV_ROUND_UP(trlt * rate, 1000000) - 1;
598 	trlt &= 0xf;
599 
600 	/* Calculate RE# pulse time in nanosecond. */
601 	temp = (trlt + 1) * 1000000 / rate;
602 	/* nanosecond to picosecond */
603 	temp *= 1000;
604 	/*
605 	 * If RE# access time is bigger than RE# pulse time,
606 	 * delay sampling data timing.
607 	 */
608 	if (temp < timings->tREA_max) {
609 		tsel = timings->tREA_max / 1000;
610 		tsel = DIV_ROUND_UP(tsel * rate, 1000000);
611 		tsel -= (trlt + 1);
612 		if (tsel > MAX_STROBE_DLY) {
613 			trlt += tsel - MAX_STROBE_DLY;
614 			tsel = MAX_STROBE_DLY;
615 		}
616 	}
617 	temp = nfi_readl(nfc, NFI_DEBUG_CON1);
618 	temp &= ~STROBE_MASK;
619 	temp |= tsel << STROBE_SHIFT;
620 	nfi_writel(nfc, temp, NFI_DEBUG_CON1);
621 
622 	/*
623 	 * ACCON: access timing control register
624 	 * -------------------------------------
625 	 * 31:28: tpoecs, minimum required time for CS post pulling down after
626 	 *        accessing the device
627 	 * 27:22: tprecs, minimum required time for CS pre pulling down before
628 	 *        accessing the device
629 	 * 21:16: tc2r, minimum required time from NCEB low to NREB low
630 	 * 15:12: tw2r, minimum required time from NWEB high to NREB low.
631 	 * 11:08: twh, write enable hold time
632 	 * 07:04: twst, write wait states
633 	 * 03:00: trlt, read wait states
634 	 */
635 	trlt = ACCTIMING(tpoecs, tprecs, tc2r, tw2r, twh, twst, trlt);
636 	nfi_writel(nfc, trlt, NFI_ACCCON);
637 
638 	return 0;
639 }
640 
641 static int mtk_nfc_sector_encode(struct nand_chip *chip, u8 *data)
642 {
643 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
644 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
645 	int size = chip->ecc.size + mtk_nand->fdm.reg_size;
646 
647 	nfc->ecc_cfg.mode = ECC_DMA_MODE;
648 	nfc->ecc_cfg.op = ECC_ENCODE;
649 
650 	return mtk_ecc_encode(nfc->ecc, &nfc->ecc_cfg, data, size);
651 }
652 
653 static void mtk_nfc_no_bad_mark_swap(struct mtd_info *a, u8 *b, int c)
654 {
655 	/* nop */
656 }
657 
658 static void mtk_nfc_bad_mark_swap(struct mtd_info *mtd, u8 *buf, int raw)
659 {
660 	struct nand_chip *chip = mtd_to_nand(mtd);
661 	struct mtk_nfc_nand_chip *nand = to_mtk_nand(chip);
662 	u32 bad_pos = nand->bad_mark.pos;
663 
664 	if (raw)
665 		bad_pos += nand->bad_mark.sec * mtk_data_len(chip);
666 	else
667 		bad_pos += nand->bad_mark.sec * chip->ecc.size;
668 
669 	swap(chip->oob_poi[0], buf[bad_pos]);
670 }
671 
672 static int mtk_nfc_format_subpage(struct mtd_info *mtd, u32 offset,
673 				  u32 len, const u8 *buf)
674 {
675 	struct nand_chip *chip = mtd_to_nand(mtd);
676 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
677 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
678 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
679 	u32 start, end;
680 	int i, ret;
681 
682 	start = offset / chip->ecc.size;
683 	end = DIV_ROUND_UP(offset + len, chip->ecc.size);
684 
685 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
686 	for (i = 0; i < chip->ecc.steps; i++) {
687 		memcpy(mtk_data_ptr(chip, i), data_ptr(chip, buf, i),
688 		       chip->ecc.size);
689 
690 		if (start > i || i >= end)
691 			continue;
692 
693 		if (i == mtk_nand->bad_mark.sec)
694 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
695 
696 		memcpy(mtk_oob_ptr(chip, i), oob_ptr(chip, i), fdm->reg_size);
697 
698 		/* program the CRC back to the OOB */
699 		ret = mtk_nfc_sector_encode(chip, mtk_data_ptr(chip, i));
700 		if (ret < 0)
701 			return ret;
702 	}
703 
704 	return 0;
705 }
706 
707 static void mtk_nfc_format_page(struct mtd_info *mtd, const u8 *buf)
708 {
709 	struct nand_chip *chip = mtd_to_nand(mtd);
710 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
711 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
712 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
713 	u32 i;
714 
715 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
716 	for (i = 0; i < chip->ecc.steps; i++) {
717 		if (buf)
718 			memcpy(mtk_data_ptr(chip, i), data_ptr(chip, buf, i),
719 			       chip->ecc.size);
720 
721 		if (i == mtk_nand->bad_mark.sec)
722 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
723 
724 		memcpy(mtk_oob_ptr(chip, i), oob_ptr(chip, i), fdm->reg_size);
725 	}
726 }
727 
728 static inline void mtk_nfc_read_fdm(struct nand_chip *chip, u32 start,
729 				    u32 sectors)
730 {
731 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
732 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
733 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
734 	u32 vall, valm;
735 	u8 *oobptr;
736 	int i, j;
737 
738 	for (i = 0; i < sectors; i++) {
739 		oobptr = oob_ptr(chip, start + i);
740 		vall = nfi_readl(nfc, NFI_FDML(i));
741 		valm = nfi_readl(nfc, NFI_FDMM(i));
742 
743 		for (j = 0; j < fdm->reg_size; j++)
744 			oobptr[j] = (j >= 4 ? valm : vall) >> ((j % 4) * 8);
745 	}
746 }
747 
748 static inline void mtk_nfc_write_fdm(struct nand_chip *chip)
749 {
750 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
751 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
752 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
753 	u32 vall, valm;
754 	u8 *oobptr;
755 	int i, j;
756 
757 	for (i = 0; i < chip->ecc.steps; i++) {
758 		oobptr = oob_ptr(chip, i);
759 		vall = 0;
760 		valm = 0;
761 		for (j = 0; j < 8; j++) {
762 			if (j < 4)
763 				vall |= (j < fdm->reg_size ? oobptr[j] : 0xff)
764 						<< (j * 8);
765 			else
766 				valm |= (j < fdm->reg_size ? oobptr[j] : 0xff)
767 						<< ((j - 4) * 8);
768 		}
769 		nfi_writel(nfc, vall, NFI_FDML(i));
770 		nfi_writel(nfc, valm, NFI_FDMM(i));
771 	}
772 }
773 
774 static int mtk_nfc_do_write_page(struct mtd_info *mtd, struct nand_chip *chip,
775 				 const u8 *buf, int page, int len)
776 {
777 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
778 	struct device *dev = nfc->dev;
779 	dma_addr_t addr;
780 	u32 reg;
781 	int ret;
782 
783 	addr = dma_map_single(dev, (void *)buf, len, DMA_TO_DEVICE);
784 	ret = dma_mapping_error(nfc->dev, addr);
785 	if (ret) {
786 		dev_err(nfc->dev, "dma mapping error\n");
787 		return -EINVAL;
788 	}
789 
790 	reg = nfi_readw(nfc, NFI_CNFG) | CNFG_AHB | CNFG_DMA_BURST_EN;
791 	nfi_writew(nfc, reg, NFI_CNFG);
792 
793 	nfi_writel(nfc, chip->ecc.steps << CON_SEC_SHIFT, NFI_CON);
794 	nfi_writel(nfc, lower_32_bits(addr), NFI_STRADDR);
795 	nfi_writew(nfc, INTR_AHB_DONE_EN, NFI_INTR_EN);
796 
797 	init_completion(&nfc->done);
798 
799 	reg = nfi_readl(nfc, NFI_CON) | CON_BWR;
800 	nfi_writel(nfc, reg, NFI_CON);
801 	nfi_writew(nfc, STAR_EN, NFI_STRDATA);
802 
803 	ret = wait_for_completion_timeout(&nfc->done, msecs_to_jiffies(500));
804 	if (!ret) {
805 		dev_err(dev, "program ahb done timeout\n");
806 		nfi_writew(nfc, 0, NFI_INTR_EN);
807 		ret = -ETIMEDOUT;
808 		goto timeout;
809 	}
810 
811 	ret = readl_poll_timeout_atomic(nfc->regs + NFI_ADDRCNTR, reg,
812 					ADDRCNTR_SEC(reg) >= chip->ecc.steps,
813 					10, MTK_TIMEOUT);
814 	if (ret)
815 		dev_err(dev, "hwecc write timeout\n");
816 
817 timeout:
818 
819 	dma_unmap_single(nfc->dev, addr, len, DMA_TO_DEVICE);
820 	nfi_writel(nfc, 0, NFI_CON);
821 
822 	return ret;
823 }
824 
825 static int mtk_nfc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
826 			      const u8 *buf, int page, int raw)
827 {
828 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
829 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
830 	size_t len;
831 	const u8 *bufpoi;
832 	u32 reg;
833 	int ret;
834 
835 	mtk_nfc_select_target(chip, chip->cur_cs);
836 	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
837 
838 	if (!raw) {
839 		/* OOB => FDM: from register,  ECC: from HW */
840 		reg = nfi_readw(nfc, NFI_CNFG) | CNFG_AUTO_FMT_EN;
841 		nfi_writew(nfc, reg | CNFG_HW_ECC_EN, NFI_CNFG);
842 
843 		nfc->ecc_cfg.op = ECC_ENCODE;
844 		nfc->ecc_cfg.mode = ECC_NFI_MODE;
845 		ret = mtk_ecc_enable(nfc->ecc, &nfc->ecc_cfg);
846 		if (ret) {
847 			/* clear NFI config */
848 			reg = nfi_readw(nfc, NFI_CNFG);
849 			reg &= ~(CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
850 			nfi_writew(nfc, reg, NFI_CNFG);
851 
852 			return ret;
853 		}
854 
855 		memcpy(nfc->buffer, buf, mtd->writesize);
856 		mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, raw);
857 		bufpoi = nfc->buffer;
858 
859 		/* write OOB into the FDM registers (OOB area in MTK NAND) */
860 		mtk_nfc_write_fdm(chip);
861 	} else {
862 		bufpoi = buf;
863 	}
864 
865 	len = mtd->writesize + (raw ? mtd->oobsize : 0);
866 	ret = mtk_nfc_do_write_page(mtd, chip, bufpoi, page, len);
867 
868 	if (!raw)
869 		mtk_ecc_disable(nfc->ecc);
870 
871 	if (ret)
872 		return ret;
873 
874 	return nand_prog_page_end_op(chip);
875 }
876 
877 static int mtk_nfc_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
878 				    int oob_on, int page)
879 {
880 	return mtk_nfc_write_page(nand_to_mtd(chip), chip, buf, page, 0);
881 }
882 
883 static int mtk_nfc_write_page_raw(struct nand_chip *chip, const u8 *buf,
884 				  int oob_on, int pg)
885 {
886 	struct mtd_info *mtd = nand_to_mtd(chip);
887 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
888 
889 	mtk_nfc_format_page(mtd, buf);
890 	return mtk_nfc_write_page(mtd, chip, nfc->buffer, pg, 1);
891 }
892 
893 static int mtk_nfc_write_subpage_hwecc(struct nand_chip *chip, u32 offset,
894 				       u32 data_len, const u8 *buf,
895 				       int oob_on, int page)
896 {
897 	struct mtd_info *mtd = nand_to_mtd(chip);
898 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
899 	int ret;
900 
901 	ret = mtk_nfc_format_subpage(mtd, offset, data_len, buf);
902 	if (ret < 0)
903 		return ret;
904 
905 	/* use the data in the private buffer (now with FDM and CRC) */
906 	return mtk_nfc_write_page(mtd, chip, nfc->buffer, page, 1);
907 }
908 
909 static int mtk_nfc_write_oob_std(struct nand_chip *chip, int page)
910 {
911 	return mtk_nfc_write_page_raw(chip, NULL, 1, page);
912 }
913 
914 static int mtk_nfc_update_ecc_stats(struct mtd_info *mtd, u8 *buf, u32 start,
915 				    u32 sectors)
916 {
917 	struct nand_chip *chip = mtd_to_nand(mtd);
918 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
919 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
920 	struct mtk_ecc_stats stats;
921 	u32 reg_size = mtk_nand->fdm.reg_size;
922 	int rc, i;
923 
924 	rc = nfi_readl(nfc, NFI_STA) & STA_EMP_PAGE;
925 	if (rc) {
926 		memset(buf, 0xff, sectors * chip->ecc.size);
927 		for (i = 0; i < sectors; i++)
928 			memset(oob_ptr(chip, start + i), 0xff, reg_size);
929 		return 0;
930 	}
931 
932 	mtk_ecc_get_stats(nfc->ecc, &stats, sectors);
933 	mtd->ecc_stats.corrected += stats.corrected;
934 	mtd->ecc_stats.failed += stats.failed;
935 
936 	return stats.bitflips;
937 }
938 
939 static int mtk_nfc_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
940 				u32 data_offs, u32 readlen,
941 				u8 *bufpoi, int page, int raw)
942 {
943 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
944 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
945 	u32 spare = mtk_nand->spare_per_sector;
946 	u32 column, sectors, start, end, reg;
947 	dma_addr_t addr;
948 	int bitflips = 0;
949 	size_t len;
950 	u8 *buf;
951 	int rc;
952 
953 	mtk_nfc_select_target(chip, chip->cur_cs);
954 	start = data_offs / chip->ecc.size;
955 	end = DIV_ROUND_UP(data_offs + readlen, chip->ecc.size);
956 
957 	sectors = end - start;
958 	column = start * (chip->ecc.size + spare);
959 
960 	len = sectors * chip->ecc.size + (raw ? sectors * spare : 0);
961 	buf = bufpoi + start * chip->ecc.size;
962 
963 	nand_read_page_op(chip, page, column, NULL, 0);
964 
965 	addr = dma_map_single(nfc->dev, buf, len, DMA_FROM_DEVICE);
966 	rc = dma_mapping_error(nfc->dev, addr);
967 	if (rc) {
968 		dev_err(nfc->dev, "dma mapping error\n");
969 
970 		return -EINVAL;
971 	}
972 
973 	reg = nfi_readw(nfc, NFI_CNFG);
974 	reg |= CNFG_READ_EN | CNFG_DMA_BURST_EN | CNFG_AHB;
975 	if (!raw) {
976 		reg |= CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN;
977 		nfi_writew(nfc, reg, NFI_CNFG);
978 
979 		nfc->ecc_cfg.mode = ECC_NFI_MODE;
980 		nfc->ecc_cfg.sectors = sectors;
981 		nfc->ecc_cfg.op = ECC_DECODE;
982 		rc = mtk_ecc_enable(nfc->ecc, &nfc->ecc_cfg);
983 		if (rc) {
984 			dev_err(nfc->dev, "ecc enable\n");
985 			/* clear NFI_CNFG */
986 			reg &= ~(CNFG_DMA_BURST_EN | CNFG_AHB | CNFG_READ_EN |
987 				CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
988 			nfi_writew(nfc, reg, NFI_CNFG);
989 			dma_unmap_single(nfc->dev, addr, len, DMA_FROM_DEVICE);
990 
991 			return rc;
992 		}
993 	} else {
994 		nfi_writew(nfc, reg, NFI_CNFG);
995 	}
996 
997 	nfi_writel(nfc, sectors << CON_SEC_SHIFT, NFI_CON);
998 	nfi_writew(nfc, INTR_AHB_DONE_EN, NFI_INTR_EN);
999 	nfi_writel(nfc, lower_32_bits(addr), NFI_STRADDR);
1000 
1001 	init_completion(&nfc->done);
1002 	reg = nfi_readl(nfc, NFI_CON) | CON_BRD;
1003 	nfi_writel(nfc, reg, NFI_CON);
1004 	nfi_writew(nfc, STAR_EN, NFI_STRDATA);
1005 
1006 	rc = wait_for_completion_timeout(&nfc->done, msecs_to_jiffies(500));
1007 	if (!rc)
1008 		dev_warn(nfc->dev, "read ahb/dma done timeout\n");
1009 
1010 	rc = readl_poll_timeout_atomic(nfc->regs + NFI_BYTELEN, reg,
1011 				       ADDRCNTR_SEC(reg) >= sectors, 10,
1012 				       MTK_TIMEOUT);
1013 	if (rc < 0) {
1014 		dev_err(nfc->dev, "subpage done timeout\n");
1015 		bitflips = -EIO;
1016 	} else if (!raw) {
1017 		rc = mtk_ecc_wait_done(nfc->ecc, ECC_DECODE);
1018 		bitflips = rc < 0 ? -ETIMEDOUT :
1019 			mtk_nfc_update_ecc_stats(mtd, buf, start, sectors);
1020 		mtk_nfc_read_fdm(chip, start, sectors);
1021 	}
1022 
1023 	dma_unmap_single(nfc->dev, addr, len, DMA_FROM_DEVICE);
1024 
1025 	if (raw)
1026 		goto done;
1027 
1028 	mtk_ecc_disable(nfc->ecc);
1029 
1030 	if (clamp(mtk_nand->bad_mark.sec, start, end) == mtk_nand->bad_mark.sec)
1031 		mtk_nand->bad_mark.bm_swap(mtd, bufpoi, raw);
1032 done:
1033 	nfi_writel(nfc, 0, NFI_CON);
1034 
1035 	return bitflips;
1036 }
1037 
1038 static int mtk_nfc_read_subpage_hwecc(struct nand_chip *chip, u32 off,
1039 				      u32 len, u8 *p, int pg)
1040 {
1041 	return mtk_nfc_read_subpage(nand_to_mtd(chip), chip, off, len, p, pg,
1042 				    0);
1043 }
1044 
1045 static int mtk_nfc_read_page_hwecc(struct nand_chip *chip, u8 *p, int oob_on,
1046 				   int pg)
1047 {
1048 	struct mtd_info *mtd = nand_to_mtd(chip);
1049 
1050 	return mtk_nfc_read_subpage(mtd, chip, 0, mtd->writesize, p, pg, 0);
1051 }
1052 
1053 static int mtk_nfc_read_page_raw(struct nand_chip *chip, u8 *buf, int oob_on,
1054 				 int page)
1055 {
1056 	struct mtd_info *mtd = nand_to_mtd(chip);
1057 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1058 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
1059 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
1060 	int i, ret;
1061 
1062 	memset(nfc->buffer, 0xff, mtd->writesize + mtd->oobsize);
1063 	ret = mtk_nfc_read_subpage(mtd, chip, 0, mtd->writesize, nfc->buffer,
1064 				   page, 1);
1065 	if (ret < 0)
1066 		return ret;
1067 
1068 	for (i = 0; i < chip->ecc.steps; i++) {
1069 		memcpy(oob_ptr(chip, i), mtk_oob_ptr(chip, i), fdm->reg_size);
1070 
1071 		if (i == mtk_nand->bad_mark.sec)
1072 			mtk_nand->bad_mark.bm_swap(mtd, nfc->buffer, 1);
1073 
1074 		if (buf)
1075 			memcpy(data_ptr(chip, buf, i), mtk_data_ptr(chip, i),
1076 			       chip->ecc.size);
1077 	}
1078 
1079 	return ret;
1080 }
1081 
1082 static int mtk_nfc_read_oob_std(struct nand_chip *chip, int page)
1083 {
1084 	return mtk_nfc_read_page_raw(chip, NULL, 1, page);
1085 }
1086 
1087 static inline void mtk_nfc_hw_init(struct mtk_nfc *nfc)
1088 {
1089 	/*
1090 	 * CNRNB: nand ready/busy register
1091 	 * -------------------------------
1092 	 * 7:4: timeout register for polling the NAND busy/ready signal
1093 	 * 0  : poll the status of the busy/ready signal after [7:4]*16 cycles.
1094 	 */
1095 	nfi_writew(nfc, 0xf1, NFI_CNRNB);
1096 	nfi_writel(nfc, PAGEFMT_8K_16K, NFI_PAGEFMT);
1097 
1098 	mtk_nfc_hw_reset(nfc);
1099 
1100 	nfi_readl(nfc, NFI_INTR_STA);
1101 	nfi_writel(nfc, 0, NFI_INTR_EN);
1102 }
1103 
1104 static irqreturn_t mtk_nfc_irq(int irq, void *id)
1105 {
1106 	struct mtk_nfc *nfc = id;
1107 	u16 sta, ien;
1108 
1109 	sta = nfi_readw(nfc, NFI_INTR_STA);
1110 	ien = nfi_readw(nfc, NFI_INTR_EN);
1111 
1112 	if (!(sta & ien))
1113 		return IRQ_NONE;
1114 
1115 	nfi_writew(nfc, ~sta & ien, NFI_INTR_EN);
1116 	complete(&nfc->done);
1117 
1118 	return IRQ_HANDLED;
1119 }
1120 
1121 static int mtk_nfc_ooblayout_free(struct mtd_info *mtd, int section,
1122 				  struct mtd_oob_region *oob_region)
1123 {
1124 	struct nand_chip *chip = mtd_to_nand(mtd);
1125 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1126 	struct mtk_nfc_fdm *fdm = &mtk_nand->fdm;
1127 	u32 eccsteps;
1128 
1129 	eccsteps = mtd->writesize / chip->ecc.size;
1130 
1131 	if (section >= eccsteps)
1132 		return -ERANGE;
1133 
1134 	oob_region->length = fdm->reg_size - fdm->ecc_size;
1135 	oob_region->offset = section * fdm->reg_size + fdm->ecc_size;
1136 
1137 	return 0;
1138 }
1139 
1140 static int mtk_nfc_ooblayout_ecc(struct mtd_info *mtd, int section,
1141 				 struct mtd_oob_region *oob_region)
1142 {
1143 	struct nand_chip *chip = mtd_to_nand(mtd);
1144 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1145 	u32 eccsteps;
1146 
1147 	if (section)
1148 		return -ERANGE;
1149 
1150 	eccsteps = mtd->writesize / chip->ecc.size;
1151 	oob_region->offset = mtk_nand->fdm.reg_size * eccsteps;
1152 	oob_region->length = mtd->oobsize - oob_region->offset;
1153 
1154 	return 0;
1155 }
1156 
1157 static const struct mtd_ooblayout_ops mtk_nfc_ooblayout_ops = {
1158 	.free = mtk_nfc_ooblayout_free,
1159 	.ecc = mtk_nfc_ooblayout_ecc,
1160 };
1161 
1162 static void mtk_nfc_set_fdm(struct mtk_nfc_fdm *fdm, struct mtd_info *mtd)
1163 {
1164 	struct nand_chip *nand = mtd_to_nand(mtd);
1165 	struct mtk_nfc_nand_chip *chip = to_mtk_nand(nand);
1166 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1167 	u32 ecc_bytes;
1168 
1169 	ecc_bytes = DIV_ROUND_UP(nand->ecc.strength *
1170 				 mtk_ecc_get_parity_bits(nfc->ecc), 8);
1171 
1172 	fdm->reg_size = chip->spare_per_sector - ecc_bytes;
1173 	if (fdm->reg_size > NFI_FDM_MAX_SIZE)
1174 		fdm->reg_size = NFI_FDM_MAX_SIZE;
1175 
1176 	/* bad block mark storage */
1177 	fdm->ecc_size = 1;
1178 }
1179 
1180 static void mtk_nfc_set_bad_mark_ctl(struct mtk_nfc_bad_mark_ctl *bm_ctl,
1181 				     struct mtd_info *mtd)
1182 {
1183 	struct nand_chip *nand = mtd_to_nand(mtd);
1184 
1185 	if (mtd->writesize == 512) {
1186 		bm_ctl->bm_swap = mtk_nfc_no_bad_mark_swap;
1187 	} else {
1188 		bm_ctl->bm_swap = mtk_nfc_bad_mark_swap;
1189 		bm_ctl->sec = mtd->writesize / mtk_data_len(nand);
1190 		bm_ctl->pos = mtd->writesize % mtk_data_len(nand);
1191 	}
1192 }
1193 
1194 static int mtk_nfc_set_spare_per_sector(u32 *sps, struct mtd_info *mtd)
1195 {
1196 	struct nand_chip *nand = mtd_to_nand(mtd);
1197 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1198 	const u8 *spare = nfc->caps->spare_size;
1199 	u32 eccsteps, i, closest_spare = 0;
1200 
1201 	eccsteps = mtd->writesize / nand->ecc.size;
1202 	*sps = mtd->oobsize / eccsteps;
1203 
1204 	if (nand->ecc.size == 1024)
1205 		*sps >>= 1;
1206 
1207 	if (*sps < MTK_NFC_MIN_SPARE)
1208 		return -EINVAL;
1209 
1210 	for (i = 0; i < nfc->caps->num_spare_size; i++) {
1211 		if (*sps >= spare[i] && spare[i] >= spare[closest_spare]) {
1212 			closest_spare = i;
1213 			if (*sps == spare[i])
1214 				break;
1215 		}
1216 	}
1217 
1218 	*sps = spare[closest_spare];
1219 
1220 	if (nand->ecc.size == 1024)
1221 		*sps <<= 1;
1222 
1223 	return 0;
1224 }
1225 
1226 static int mtk_nfc_ecc_init(struct device *dev, struct mtd_info *mtd)
1227 {
1228 	struct nand_chip *nand = mtd_to_nand(mtd);
1229 	const struct nand_ecc_props *requirements =
1230 		nanddev_get_ecc_requirements(&nand->base);
1231 	struct mtk_nfc *nfc = nand_get_controller_data(nand);
1232 	u32 spare;
1233 	int free, ret;
1234 
1235 	/* support only ecc hw mode */
1236 	if (nand->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST) {
1237 		dev_err(dev, "ecc.engine_type not supported\n");
1238 		return -EINVAL;
1239 	}
1240 
1241 	/* if optional dt settings not present */
1242 	if (!nand->ecc.size || !nand->ecc.strength) {
1243 		/* use datasheet requirements */
1244 		nand->ecc.strength = requirements->strength;
1245 		nand->ecc.size = requirements->step_size;
1246 
1247 		/*
1248 		 * align eccstrength and eccsize
1249 		 * this controller only supports 512 and 1024 sizes
1250 		 */
1251 		if (nand->ecc.size < 1024) {
1252 			if (mtd->writesize > 512 &&
1253 			    nfc->caps->max_sector_size > 512) {
1254 				nand->ecc.size = 1024;
1255 				nand->ecc.strength <<= 1;
1256 			} else {
1257 				nand->ecc.size = 512;
1258 			}
1259 		} else {
1260 			nand->ecc.size = 1024;
1261 		}
1262 
1263 		ret = mtk_nfc_set_spare_per_sector(&spare, mtd);
1264 		if (ret)
1265 			return ret;
1266 
1267 		/* calculate oob bytes except ecc parity data */
1268 		free = (nand->ecc.strength * mtk_ecc_get_parity_bits(nfc->ecc)
1269 			+ 7) >> 3;
1270 		free = spare - free;
1271 
1272 		/*
1273 		 * enhance ecc strength if oob left is bigger than max FDM size
1274 		 * or reduce ecc strength if oob size is not enough for ecc
1275 		 * parity data.
1276 		 */
1277 		if (free > NFI_FDM_MAX_SIZE) {
1278 			spare -= NFI_FDM_MAX_SIZE;
1279 			nand->ecc.strength = (spare << 3) /
1280 					     mtk_ecc_get_parity_bits(nfc->ecc);
1281 		} else if (free < 0) {
1282 			spare -= NFI_FDM_MIN_SIZE;
1283 			nand->ecc.strength = (spare << 3) /
1284 					     mtk_ecc_get_parity_bits(nfc->ecc);
1285 		}
1286 	}
1287 
1288 	mtk_ecc_adjust_strength(nfc->ecc, &nand->ecc.strength);
1289 
1290 	dev_info(dev, "eccsize %d eccstrength %d\n",
1291 		 nand->ecc.size, nand->ecc.strength);
1292 
1293 	return 0;
1294 }
1295 
1296 static int mtk_nfc_attach_chip(struct nand_chip *chip)
1297 {
1298 	struct mtd_info *mtd = nand_to_mtd(chip);
1299 	struct device *dev = mtd->dev.parent;
1300 	struct mtk_nfc *nfc = nand_get_controller_data(chip);
1301 	struct mtk_nfc_nand_chip *mtk_nand = to_mtk_nand(chip);
1302 	int len;
1303 	int ret;
1304 
1305 	if (chip->options & NAND_BUSWIDTH_16) {
1306 		dev_err(dev, "16bits buswidth not supported");
1307 		return -EINVAL;
1308 	}
1309 
1310 	/* store bbt magic in page, cause OOB is not protected */
1311 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1312 		chip->bbt_options |= NAND_BBT_NO_OOB;
1313 
1314 	ret = mtk_nfc_ecc_init(dev, mtd);
1315 	if (ret)
1316 		return ret;
1317 
1318 	ret = mtk_nfc_set_spare_per_sector(&mtk_nand->spare_per_sector, mtd);
1319 	if (ret)
1320 		return ret;
1321 
1322 	mtk_nfc_set_fdm(&mtk_nand->fdm, mtd);
1323 	mtk_nfc_set_bad_mark_ctl(&mtk_nand->bad_mark, mtd);
1324 
1325 	len = mtd->writesize + mtd->oobsize;
1326 	nfc->buffer = devm_kzalloc(dev, len, GFP_KERNEL);
1327 	if (!nfc->buffer)
1328 		return  -ENOMEM;
1329 
1330 	return 0;
1331 }
1332 
1333 static const struct nand_controller_ops mtk_nfc_controller_ops = {
1334 	.attach_chip = mtk_nfc_attach_chip,
1335 	.setup_interface = mtk_nfc_setup_interface,
1336 	.exec_op = mtk_nfc_exec_op,
1337 };
1338 
1339 static int mtk_nfc_nand_chip_init(struct device *dev, struct mtk_nfc *nfc,
1340 				  struct device_node *np)
1341 {
1342 	struct mtk_nfc_nand_chip *chip;
1343 	struct nand_chip *nand;
1344 	struct mtd_info *mtd;
1345 	int nsels;
1346 	u32 tmp;
1347 	int ret;
1348 	int i;
1349 
1350 	if (!of_get_property(np, "reg", &nsels))
1351 		return -ENODEV;
1352 
1353 	nsels /= sizeof(u32);
1354 	if (!nsels || nsels > MTK_NAND_MAX_NSELS) {
1355 		dev_err(dev, "invalid reg property size %d\n", nsels);
1356 		return -EINVAL;
1357 	}
1358 
1359 	chip = devm_kzalloc(dev, sizeof(*chip) + nsels * sizeof(u8),
1360 			    GFP_KERNEL);
1361 	if (!chip)
1362 		return -ENOMEM;
1363 
1364 	chip->nsels = nsels;
1365 	for (i = 0; i < nsels; i++) {
1366 		ret = of_property_read_u32_index(np, "reg", i, &tmp);
1367 		if (ret) {
1368 			dev_err(dev, "reg property failure : %d\n", ret);
1369 			return ret;
1370 		}
1371 
1372 		if (tmp >= MTK_NAND_MAX_NSELS) {
1373 			dev_err(dev, "invalid CS: %u\n", tmp);
1374 			return -EINVAL;
1375 		}
1376 
1377 		if (test_and_set_bit(tmp, &nfc->assigned_cs)) {
1378 			dev_err(dev, "CS %u already assigned\n", tmp);
1379 			return -EINVAL;
1380 		}
1381 
1382 		chip->sels[i] = tmp;
1383 	}
1384 
1385 	nand = &chip->nand;
1386 	nand->controller = &nfc->controller;
1387 
1388 	nand_set_flash_node(nand, np);
1389 	nand_set_controller_data(nand, nfc);
1390 
1391 	nand->options |= NAND_USES_DMA | NAND_SUBPAGE_READ;
1392 
1393 	/* set default mode in case dt entry is missing */
1394 	nand->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
1395 
1396 	nand->ecc.write_subpage = mtk_nfc_write_subpage_hwecc;
1397 	nand->ecc.write_page_raw = mtk_nfc_write_page_raw;
1398 	nand->ecc.write_page = mtk_nfc_write_page_hwecc;
1399 	nand->ecc.write_oob_raw = mtk_nfc_write_oob_std;
1400 	nand->ecc.write_oob = mtk_nfc_write_oob_std;
1401 
1402 	nand->ecc.read_subpage = mtk_nfc_read_subpage_hwecc;
1403 	nand->ecc.read_page_raw = mtk_nfc_read_page_raw;
1404 	nand->ecc.read_page = mtk_nfc_read_page_hwecc;
1405 	nand->ecc.read_oob_raw = mtk_nfc_read_oob_std;
1406 	nand->ecc.read_oob = mtk_nfc_read_oob_std;
1407 
1408 	mtd = nand_to_mtd(nand);
1409 	mtd->owner = THIS_MODULE;
1410 	mtd->dev.parent = dev;
1411 	mtd->name = MTK_NAME;
1412 	mtd_set_ooblayout(mtd, &mtk_nfc_ooblayout_ops);
1413 
1414 	mtk_nfc_hw_init(nfc);
1415 
1416 	ret = nand_scan(nand, nsels);
1417 	if (ret)
1418 		return ret;
1419 
1420 	ret = mtd_device_register(mtd, NULL, 0);
1421 	if (ret) {
1422 		dev_err(dev, "mtd parse partition error\n");
1423 		nand_cleanup(nand);
1424 		return ret;
1425 	}
1426 
1427 	list_add_tail(&chip->node, &nfc->chips);
1428 
1429 	return 0;
1430 }
1431 
1432 static int mtk_nfc_nand_chips_init(struct device *dev, struct mtk_nfc *nfc)
1433 {
1434 	struct device_node *np = dev->of_node;
1435 	struct device_node *nand_np;
1436 	int ret;
1437 
1438 	for_each_child_of_node(np, nand_np) {
1439 		ret = mtk_nfc_nand_chip_init(dev, nfc, nand_np);
1440 		if (ret) {
1441 			of_node_put(nand_np);
1442 			return ret;
1443 		}
1444 	}
1445 
1446 	return 0;
1447 }
1448 
1449 static const struct mtk_nfc_caps mtk_nfc_caps_mt2701 = {
1450 	.spare_size = spare_size_mt2701,
1451 	.num_spare_size = 16,
1452 	.pageformat_spare_shift = 4,
1453 	.nfi_clk_div = 1,
1454 	.max_sector = 16,
1455 	.max_sector_size = 1024,
1456 };
1457 
1458 static const struct mtk_nfc_caps mtk_nfc_caps_mt2712 = {
1459 	.spare_size = spare_size_mt2712,
1460 	.num_spare_size = 19,
1461 	.pageformat_spare_shift = 16,
1462 	.nfi_clk_div = 2,
1463 	.max_sector = 16,
1464 	.max_sector_size = 1024,
1465 };
1466 
1467 static const struct mtk_nfc_caps mtk_nfc_caps_mt7622 = {
1468 	.spare_size = spare_size_mt7622,
1469 	.num_spare_size = 4,
1470 	.pageformat_spare_shift = 4,
1471 	.nfi_clk_div = 1,
1472 	.max_sector = 8,
1473 	.max_sector_size = 512,
1474 };
1475 
1476 static const struct of_device_id mtk_nfc_id_table[] = {
1477 	{
1478 		.compatible = "mediatek,mt2701-nfc",
1479 		.data = &mtk_nfc_caps_mt2701,
1480 	}, {
1481 		.compatible = "mediatek,mt2712-nfc",
1482 		.data = &mtk_nfc_caps_mt2712,
1483 	}, {
1484 		.compatible = "mediatek,mt7622-nfc",
1485 		.data = &mtk_nfc_caps_mt7622,
1486 	},
1487 	{}
1488 };
1489 MODULE_DEVICE_TABLE(of, mtk_nfc_id_table);
1490 
1491 static int mtk_nfc_probe(struct platform_device *pdev)
1492 {
1493 	struct device *dev = &pdev->dev;
1494 	struct device_node *np = dev->of_node;
1495 	struct mtk_nfc *nfc;
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 	nfc->regs = devm_platform_ioremap_resource(pdev, 0);
1517 	if (IS_ERR(nfc->regs)) {
1518 		ret = PTR_ERR(nfc->regs);
1519 		goto release_ecc;
1520 	}
1521 
1522 	nfc->clk.nfi_clk = devm_clk_get_enabled(dev, "nfi_clk");
1523 	if (IS_ERR(nfc->clk.nfi_clk)) {
1524 		dev_err(dev, "no clk\n");
1525 		ret = PTR_ERR(nfc->clk.nfi_clk);
1526 		goto release_ecc;
1527 	}
1528 
1529 	nfc->clk.pad_clk = devm_clk_get_enabled(dev, "pad_clk");
1530 	if (IS_ERR(nfc->clk.pad_clk)) {
1531 		dev_err(dev, "no pad clk\n");
1532 		ret = PTR_ERR(nfc->clk.pad_clk);
1533 		goto release_ecc;
1534 	}
1535 
1536 	irq = platform_get_irq(pdev, 0);
1537 	if (irq < 0) {
1538 		ret = -EINVAL;
1539 		goto release_ecc;
1540 	}
1541 
1542 	ret = devm_request_irq(dev, irq, mtk_nfc_irq, 0x0, "mtk-nand", nfc);
1543 	if (ret) {
1544 		dev_err(dev, "failed to request nfi irq\n");
1545 		goto release_ecc;
1546 	}
1547 
1548 	ret = dma_set_mask(dev, DMA_BIT_MASK(32));
1549 	if (ret) {
1550 		dev_err(dev, "failed to set dma mask\n");
1551 		goto release_ecc;
1552 	}
1553 
1554 	platform_set_drvdata(pdev, nfc);
1555 
1556 	ret = mtk_nfc_nand_chips_init(dev, nfc);
1557 	if (ret) {
1558 		dev_err(dev, "failed to init nand chips\n");
1559 		goto release_ecc;
1560 	}
1561 
1562 	return 0;
1563 
1564 release_ecc:
1565 	mtk_ecc_release(nfc->ecc);
1566 
1567 	return ret;
1568 }
1569 
1570 static void mtk_nfc_remove(struct platform_device *pdev)
1571 {
1572 	struct mtk_nfc *nfc = platform_get_drvdata(pdev);
1573 	struct mtk_nfc_nand_chip *mtk_chip;
1574 	struct nand_chip *chip;
1575 	int ret;
1576 
1577 	while (!list_empty(&nfc->chips)) {
1578 		mtk_chip = list_first_entry(&nfc->chips,
1579 					    struct mtk_nfc_nand_chip, node);
1580 		chip = &mtk_chip->nand;
1581 		ret = mtd_device_unregister(nand_to_mtd(chip));
1582 		WARN_ON(ret);
1583 		nand_cleanup(chip);
1584 		list_del(&mtk_chip->node);
1585 	}
1586 
1587 	mtk_ecc_release(nfc->ecc);
1588 }
1589 
1590 #ifdef CONFIG_PM_SLEEP
1591 static int mtk_nfc_suspend(struct device *dev)
1592 {
1593 	struct mtk_nfc *nfc = dev_get_drvdata(dev);
1594 
1595 	clk_disable_unprepare(nfc->clk.nfi_clk);
1596 	clk_disable_unprepare(nfc->clk.pad_clk);
1597 
1598 	return 0;
1599 }
1600 
1601 static int mtk_nfc_resume(struct device *dev)
1602 {
1603 	struct mtk_nfc *nfc = dev_get_drvdata(dev);
1604 	struct mtk_nfc_nand_chip *chip;
1605 	struct nand_chip *nand;
1606 	int ret;
1607 	u32 i;
1608 
1609 	udelay(200);
1610 
1611 	ret = clk_prepare_enable(nfc->clk.nfi_clk);
1612 	if (ret) {
1613 		dev_err(dev, "failed to enable nfi clk\n");
1614 		return ret;
1615 	}
1616 
1617 	ret = clk_prepare_enable(nfc->clk.pad_clk);
1618 	if (ret) {
1619 		dev_err(dev, "failed to enable pad clk\n");
1620 		clk_disable_unprepare(nfc->clk.nfi_clk);
1621 		return ret;
1622 	}
1623 
1624 	/* reset NAND chip if VCC was powered off */
1625 	list_for_each_entry(chip, &nfc->chips, node) {
1626 		nand = &chip->nand;
1627 		for (i = 0; i < chip->nsels; i++)
1628 			nand_reset(nand, i);
1629 	}
1630 
1631 	return 0;
1632 }
1633 
1634 static SIMPLE_DEV_PM_OPS(mtk_nfc_pm_ops, mtk_nfc_suspend, mtk_nfc_resume);
1635 #endif
1636 
1637 static struct platform_driver mtk_nfc_driver = {
1638 	.probe  = mtk_nfc_probe,
1639 	.remove_new = mtk_nfc_remove,
1640 	.driver = {
1641 		.name  = MTK_NAME,
1642 		.of_match_table = mtk_nfc_id_table,
1643 #ifdef CONFIG_PM_SLEEP
1644 		.pm = &mtk_nfc_pm_ops,
1645 #endif
1646 	},
1647 };
1648 
1649 module_platform_driver(mtk_nfc_driver);
1650 
1651 MODULE_LICENSE("Dual MIT/GPL");
1652 MODULE_AUTHOR("Xiaolei Li <xiaolei.li@mediatek.com>");
1653 MODULE_DESCRIPTION("MTK Nand Flash Controller Driver");
1654