xref: /linux/drivers/mtd/nand/raw/sunxi_nand.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2013 Boris BREZILLON <b.brezillon.dev@gmail.com>
4  *
5  * Derived from:
6  *	https://github.com/yuq/sunxi-nfc-mtd
7  *	Copyright (C) 2013 Qiang Yu <yuq825@gmail.com>
8  *
9  *	https://github.com/hno/Allwinner-Info
10  *	Copyright (C) 2013 Henrik Nordström <Henrik Nordström>
11  *
12  *	Copyright (C) 2013 Dmitriy B. <rzk333@gmail.com>
13  *	Copyright (C) 2013 Sergey Lapin <slapin@ossfans.org>
14  */
15 
16 #include <linux/dma-mapping.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/platform_device.h>
21 #include <linux/of.h>
22 #include <linux/mtd/mtd.h>
23 #include <linux/mtd/rawnand.h>
24 #include <linux/mtd/partitions.h>
25 #include <linux/clk.h>
26 #include <linux/delay.h>
27 #include <linux/dmaengine.h>
28 #include <linux/interrupt.h>
29 #include <linux/iopoll.h>
30 #include <linux/reset.h>
31 
32 #define NFC_REG_CTL		0x0000
33 #define NFC_REG_ST		0x0004
34 #define NFC_REG_INT		0x0008
35 #define NFC_REG_TIMING_CTL	0x000C
36 #define NFC_REG_TIMING_CFG	0x0010
37 #define NFC_REG_ADDR_LOW	0x0014
38 #define NFC_REG_ADDR_HIGH	0x0018
39 #define NFC_REG_SECTOR_NUM	0x001C
40 #define NFC_REG_CNT		0x0020
41 #define NFC_REG_CMD		0x0024
42 #define NFC_REG_RCMD_SET	0x0028
43 #define NFC_REG_WCMD_SET	0x002C
44 #define NFC_REG_A10_IO_DATA	0x0030
45 #define NFC_REG_A23_IO_DATA	0x0300
46 #define NFC_REG_ECC_CTL		0x0034
47 #define NFC_REG_ECC_ST		0x0038
48 #define NFC_REG_DEBUG		0x003C
49 #define NFC_REG_ECC_ERR_CNT(x)	((0x0040 + (x)) & ~0x3)
50 #define NFC_REG_USER_DATA(x)	(0x0050 + ((x) * 4))
51 #define NFC_REG_SPARE_AREA	0x00A0
52 #define NFC_REG_PAT_ID		0x00A4
53 #define NFC_REG_MDMA_ADDR	0x00C0
54 #define NFC_REG_MDMA_CNT	0x00C4
55 #define NFC_RAM0_BASE		0x0400
56 #define NFC_RAM1_BASE		0x0800
57 
58 /* define bit use in NFC_CTL */
59 #define NFC_EN			BIT(0)
60 #define NFC_RESET		BIT(1)
61 #define NFC_BUS_WIDTH_MSK	BIT(2)
62 #define NFC_BUS_WIDTH_8		(0 << 2)
63 #define NFC_BUS_WIDTH_16	(1 << 2)
64 #define NFC_RB_SEL_MSK		BIT(3)
65 #define NFC_RB_SEL(x)		((x) << 3)
66 #define NFC_CE_SEL_MSK		GENMASK(26, 24)
67 #define NFC_CE_SEL(x)		((x) << 24)
68 #define NFC_CE_CTL		BIT(6)
69 #define NFC_PAGE_SHIFT_MSK	GENMASK(11, 8)
70 #define NFC_PAGE_SHIFT(x)	(((x) < 10 ? 0 : (x) - 10) << 8)
71 #define NFC_SAM			BIT(12)
72 #define NFC_RAM_METHOD		BIT(14)
73 #define NFC_DMA_TYPE_NORMAL	BIT(15)
74 #define NFC_DEBUG_CTL		BIT(31)
75 
76 /* define bit use in NFC_ST */
77 #define NFC_RB_B2R		BIT(0)
78 #define NFC_CMD_INT_FLAG	BIT(1)
79 #define NFC_DMA_INT_FLAG	BIT(2)
80 #define NFC_CMD_FIFO_STATUS	BIT(3)
81 #define NFC_STA			BIT(4)
82 #define NFC_NATCH_INT_FLAG	BIT(5)
83 #define NFC_RB_STATE(x)		BIT(x + 8)
84 
85 /* define bit use in NFC_INT */
86 #define NFC_B2R_INT_ENABLE	BIT(0)
87 #define NFC_CMD_INT_ENABLE	BIT(1)
88 #define NFC_DMA_INT_ENABLE	BIT(2)
89 #define NFC_INT_MASK		(NFC_B2R_INT_ENABLE | \
90 				 NFC_CMD_INT_ENABLE | \
91 				 NFC_DMA_INT_ENABLE)
92 
93 /* define bit use in NFC_TIMING_CTL */
94 #define NFC_TIMING_CTL_EDO	BIT(8)
95 
96 /* define NFC_TIMING_CFG register layout */
97 #define NFC_TIMING_CFG(tWB, tADL, tWHR, tRHW, tCAD)		\
98 	(((tWB) & 0x3) | (((tADL) & 0x3) << 2) |		\
99 	(((tWHR) & 0x3) << 4) | (((tRHW) & 0x3) << 6) |		\
100 	(((tCAD) & 0x7) << 8))
101 
102 /* define bit use in NFC_CMD */
103 #define NFC_CMD_LOW_BYTE_MSK	GENMASK(7, 0)
104 #define NFC_CMD_HIGH_BYTE_MSK	GENMASK(15, 8)
105 #define NFC_CMD(x)		(x)
106 #define NFC_ADR_NUM_MSK		GENMASK(18, 16)
107 #define NFC_ADR_NUM(x)		(((x) - 1) << 16)
108 #define NFC_SEND_ADR		BIT(19)
109 #define NFC_ACCESS_DIR		BIT(20)
110 #define NFC_DATA_TRANS		BIT(21)
111 #define NFC_SEND_CMD1		BIT(22)
112 #define NFC_WAIT_FLAG		BIT(23)
113 #define NFC_SEND_CMD2		BIT(24)
114 #define NFC_SEQ			BIT(25)
115 #define NFC_DATA_SWAP_METHOD	BIT(26)
116 #define NFC_ROW_AUTO_INC	BIT(27)
117 #define NFC_SEND_CMD3		BIT(28)
118 #define NFC_SEND_CMD4		BIT(29)
119 #define NFC_CMD_TYPE_MSK	GENMASK(31, 30)
120 #define NFC_NORMAL_OP		(0 << 30)
121 #define NFC_ECC_OP		(1 << 30)
122 #define NFC_PAGE_OP		(2U << 30)
123 
124 /* define bit use in NFC_RCMD_SET */
125 #define NFC_READ_CMD_MSK	GENMASK(7, 0)
126 #define NFC_RND_READ_CMD0_MSK	GENMASK(15, 8)
127 #define NFC_RND_READ_CMD1_MSK	GENMASK(23, 16)
128 
129 /* define bit use in NFC_WCMD_SET */
130 #define NFC_PROGRAM_CMD_MSK	GENMASK(7, 0)
131 #define NFC_RND_WRITE_CMD_MSK	GENMASK(15, 8)
132 #define NFC_READ_CMD0_MSK	GENMASK(23, 16)
133 #define NFC_READ_CMD1_MSK	GENMASK(31, 24)
134 
135 /* define bit use in NFC_ECC_CTL */
136 #define NFC_ECC_EN		BIT(0)
137 #define NFC_ECC_PIPELINE	BIT(3)
138 #define NFC_ECC_EXCEPTION	BIT(4)
139 #define NFC_ECC_BLOCK_SIZE_MSK	BIT(5)
140 #define NFC_ECC_BLOCK_512	BIT(5)
141 #define NFC_RANDOM_EN		BIT(9)
142 #define NFC_RANDOM_DIRECTION	BIT(10)
143 #define NFC_ECC_MODE_MSK	GENMASK(15, 12)
144 #define NFC_ECC_MODE(x)		((x) << 12)
145 #define NFC_RANDOM_SEED_MSK	GENMASK(30, 16)
146 #define NFC_RANDOM_SEED(x)	((x) << 16)
147 
148 /* define bit use in NFC_ECC_ST */
149 #define NFC_ECC_ERR(x)		BIT(x)
150 #define NFC_ECC_ERR_MSK		GENMASK(15, 0)
151 #define NFC_ECC_PAT_FOUND(x)	BIT(x + 16)
152 #define NFC_ECC_ERR_CNT(b, x)	(((x) >> (((b) % 4) * 8)) & 0xff)
153 
154 #define NFC_DEFAULT_TIMEOUT_MS	1000
155 
156 #define NFC_SRAM_SIZE		1024
157 
158 #define NFC_MAX_CS		7
159 
160 /**
161  * struct sunxi_nand_chip_sel - stores information related to NAND Chip Select
162  *
163  * @cs: the NAND CS id used to communicate with a NAND Chip
164  * @rb: the Ready/Busy pin ID. -1 means no R/B pin connected to the NFC
165  */
166 struct sunxi_nand_chip_sel {
167 	u8 cs;
168 	s8 rb;
169 };
170 
171 /**
172  * struct sunxi_nand_hw_ecc - stores information related to HW ECC support
173  *
174  * @ecc_ctl: ECC_CTL register value for this NAND chip
175  */
176 struct sunxi_nand_hw_ecc {
177 	u32 ecc_ctl;
178 };
179 
180 /**
181  * struct sunxi_nand_chip - stores NAND chip device related information
182  *
183  * @node: used to store NAND chips into a list
184  * @nand: base NAND chip structure
185  * @ecc: ECC controller structure
186  * @clk_rate: clk_rate required for this NAND chip
187  * @timing_cfg: TIMING_CFG register value for this NAND chip
188  * @timing_ctl: TIMING_CTL register value for this NAND chip
189  * @nsels: number of CS lines required by the NAND chip
190  * @sels: array of CS lines descriptions
191  */
192 struct sunxi_nand_chip {
193 	struct list_head node;
194 	struct nand_chip nand;
195 	struct sunxi_nand_hw_ecc ecc;
196 	unsigned long clk_rate;
197 	u32 timing_cfg;
198 	u32 timing_ctl;
199 	int nsels;
200 	struct sunxi_nand_chip_sel sels[] __counted_by(nsels);
201 };
202 
203 static inline struct sunxi_nand_chip *to_sunxi_nand(struct nand_chip *nand)
204 {
205 	return container_of(nand, struct sunxi_nand_chip, nand);
206 }
207 
208 /*
209  * NAND Controller capabilities structure: stores NAND controller capabilities
210  * for distinction between compatible strings.
211  *
212  * @has_mdma:		Use mbus dma mode, otherwise general dma
213  *			through MBUS on A23/A33 needs extra configuration.
214  * @reg_io_data:	I/O data register
215  * @dma_maxburst:	DMA maxburst
216  */
217 struct sunxi_nfc_caps {
218 	bool has_mdma;
219 	unsigned int reg_io_data;
220 	unsigned int dma_maxburst;
221 };
222 
223 /**
224  * struct sunxi_nfc - stores sunxi NAND controller information
225  *
226  * @controller: base controller structure
227  * @dev: parent device (used to print error messages)
228  * @regs: NAND controller registers
229  * @ahb_clk: NAND controller AHB clock
230  * @mod_clk: NAND controller mod clock
231  * @reset: NAND controller reset line
232  * @assigned_cs: bitmask describing already assigned CS lines
233  * @clk_rate: NAND controller current clock rate
234  * @chips: a list containing all the NAND chips attached to this NAND
235  *	   controller
236  * @complete: a completion object used to wait for NAND controller events
237  * @dmac: the DMA channel attached to the NAND controller
238  * @caps: NAND Controller capabilities
239  */
240 struct sunxi_nfc {
241 	struct nand_controller controller;
242 	struct device *dev;
243 	void __iomem *regs;
244 	struct clk *ahb_clk;
245 	struct clk *mod_clk;
246 	struct reset_control *reset;
247 	unsigned long assigned_cs;
248 	unsigned long clk_rate;
249 	struct list_head chips;
250 	struct completion complete;
251 	struct dma_chan *dmac;
252 	const struct sunxi_nfc_caps *caps;
253 };
254 
255 static inline struct sunxi_nfc *to_sunxi_nfc(struct nand_controller *ctrl)
256 {
257 	return container_of(ctrl, struct sunxi_nfc, controller);
258 }
259 
260 static irqreturn_t sunxi_nfc_interrupt(int irq, void *dev_id)
261 {
262 	struct sunxi_nfc *nfc = dev_id;
263 	u32 st = readl(nfc->regs + NFC_REG_ST);
264 	u32 ien = readl(nfc->regs + NFC_REG_INT);
265 
266 	if (!(ien & st))
267 		return IRQ_NONE;
268 
269 	if ((ien & st) == ien)
270 		complete(&nfc->complete);
271 
272 	writel(st & NFC_INT_MASK, nfc->regs + NFC_REG_ST);
273 	writel(~st & ien & NFC_INT_MASK, nfc->regs + NFC_REG_INT);
274 
275 	return IRQ_HANDLED;
276 }
277 
278 static int sunxi_nfc_wait_events(struct sunxi_nfc *nfc, u32 events,
279 				 bool use_polling, unsigned int timeout_ms)
280 {
281 	int ret;
282 
283 	if (events & ~NFC_INT_MASK)
284 		return -EINVAL;
285 
286 	if (!timeout_ms)
287 		timeout_ms = NFC_DEFAULT_TIMEOUT_MS;
288 
289 	if (!use_polling) {
290 		init_completion(&nfc->complete);
291 
292 		writel(events, nfc->regs + NFC_REG_INT);
293 
294 		ret = wait_for_completion_timeout(&nfc->complete,
295 						msecs_to_jiffies(timeout_ms));
296 		if (!ret)
297 			ret = -ETIMEDOUT;
298 		else
299 			ret = 0;
300 
301 		writel(0, nfc->regs + NFC_REG_INT);
302 	} else {
303 		u32 status;
304 
305 		ret = readl_poll_timeout(nfc->regs + NFC_REG_ST, status,
306 					 (status & events) == events, 1,
307 					 timeout_ms * 1000);
308 	}
309 
310 	writel(events & NFC_INT_MASK, nfc->regs + NFC_REG_ST);
311 
312 	if (ret)
313 		dev_err(nfc->dev, "wait interrupt timedout\n");
314 
315 	return ret;
316 }
317 
318 static int sunxi_nfc_wait_cmd_fifo_empty(struct sunxi_nfc *nfc)
319 {
320 	u32 status;
321 	int ret;
322 
323 	ret = readl_poll_timeout(nfc->regs + NFC_REG_ST, status,
324 				 !(status & NFC_CMD_FIFO_STATUS), 1,
325 				 NFC_DEFAULT_TIMEOUT_MS * 1000);
326 	if (ret)
327 		dev_err(nfc->dev, "wait for empty cmd FIFO timedout\n");
328 
329 	return ret;
330 }
331 
332 static int sunxi_nfc_rst(struct sunxi_nfc *nfc)
333 {
334 	u32 ctl;
335 	int ret;
336 
337 	writel(0, nfc->regs + NFC_REG_ECC_CTL);
338 	writel(NFC_RESET, nfc->regs + NFC_REG_CTL);
339 
340 	ret = readl_poll_timeout(nfc->regs + NFC_REG_CTL, ctl,
341 				 !(ctl & NFC_RESET), 1,
342 				 NFC_DEFAULT_TIMEOUT_MS * 1000);
343 	if (ret)
344 		dev_err(nfc->dev, "wait for NAND controller reset timedout\n");
345 
346 	return ret;
347 }
348 
349 static int sunxi_nfc_dma_op_prepare(struct sunxi_nfc *nfc, const void *buf,
350 				    int chunksize, int nchunks,
351 				    enum dma_data_direction ddir,
352 				    struct scatterlist *sg)
353 {
354 	struct dma_async_tx_descriptor *dmad;
355 	enum dma_transfer_direction tdir;
356 	dma_cookie_t dmat;
357 	int ret;
358 
359 	if (ddir == DMA_FROM_DEVICE)
360 		tdir = DMA_DEV_TO_MEM;
361 	else
362 		tdir = DMA_MEM_TO_DEV;
363 
364 	sg_init_one(sg, buf, nchunks * chunksize);
365 	ret = dma_map_sg(nfc->dev, sg, 1, ddir);
366 	if (!ret)
367 		return -ENOMEM;
368 
369 	if (!nfc->caps->has_mdma) {
370 		dmad = dmaengine_prep_slave_sg(nfc->dmac, sg, 1, tdir, DMA_CTRL_ACK);
371 		if (!dmad) {
372 			ret = -EINVAL;
373 			goto err_unmap_buf;
374 		}
375 	}
376 
377 	writel(readl(nfc->regs + NFC_REG_CTL) | NFC_RAM_METHOD,
378 	       nfc->regs + NFC_REG_CTL);
379 	writel(nchunks, nfc->regs + NFC_REG_SECTOR_NUM);
380 	writel(chunksize, nfc->regs + NFC_REG_CNT);
381 
382 	if (nfc->caps->has_mdma) {
383 		writel(readl(nfc->regs + NFC_REG_CTL) & ~NFC_DMA_TYPE_NORMAL,
384 		       nfc->regs + NFC_REG_CTL);
385 		writel(chunksize * nchunks, nfc->regs + NFC_REG_MDMA_CNT);
386 		writel(sg_dma_address(sg), nfc->regs + NFC_REG_MDMA_ADDR);
387 	} else {
388 		dmat = dmaengine_submit(dmad);
389 
390 		ret = dma_submit_error(dmat);
391 		if (ret)
392 			goto err_clr_dma_flag;
393 	}
394 
395 	return 0;
396 
397 err_clr_dma_flag:
398 	writel(readl(nfc->regs + NFC_REG_CTL) & ~NFC_RAM_METHOD,
399 	       nfc->regs + NFC_REG_CTL);
400 
401 err_unmap_buf:
402 	dma_unmap_sg(nfc->dev, sg, 1, ddir);
403 	return ret;
404 }
405 
406 static void sunxi_nfc_dma_op_cleanup(struct sunxi_nfc *nfc,
407 				     enum dma_data_direction ddir,
408 				     struct scatterlist *sg)
409 {
410 	dma_unmap_sg(nfc->dev, sg, 1, ddir);
411 	writel(readl(nfc->regs + NFC_REG_CTL) & ~NFC_RAM_METHOD,
412 	       nfc->regs + NFC_REG_CTL);
413 }
414 
415 static void sunxi_nfc_select_chip(struct nand_chip *nand, unsigned int cs)
416 {
417 	struct mtd_info *mtd = nand_to_mtd(nand);
418 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
419 	struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
420 	struct sunxi_nand_chip_sel *sel;
421 	u32 ctl;
422 
423 	if (cs >= sunxi_nand->nsels)
424 		return;
425 
426 	ctl = readl(nfc->regs + NFC_REG_CTL) &
427 	      ~(NFC_PAGE_SHIFT_MSK | NFC_CE_SEL_MSK | NFC_RB_SEL_MSK | NFC_EN);
428 
429 	sel = &sunxi_nand->sels[cs];
430 	ctl |= NFC_CE_SEL(sel->cs) | NFC_EN | NFC_PAGE_SHIFT(nand->page_shift);
431 	if (sel->rb >= 0)
432 		ctl |= NFC_RB_SEL(sel->rb);
433 
434 	writel(mtd->writesize, nfc->regs + NFC_REG_SPARE_AREA);
435 
436 	if (nfc->clk_rate != sunxi_nand->clk_rate) {
437 		clk_set_rate(nfc->mod_clk, sunxi_nand->clk_rate);
438 		nfc->clk_rate = sunxi_nand->clk_rate;
439 	}
440 
441 	writel(sunxi_nand->timing_ctl, nfc->regs + NFC_REG_TIMING_CTL);
442 	writel(sunxi_nand->timing_cfg, nfc->regs + NFC_REG_TIMING_CFG);
443 	writel(ctl, nfc->regs + NFC_REG_CTL);
444 }
445 
446 static void sunxi_nfc_read_buf(struct nand_chip *nand, uint8_t *buf, int len)
447 {
448 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
449 	struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
450 	int ret;
451 	int cnt;
452 	int offs = 0;
453 	u32 tmp;
454 
455 	while (len > offs) {
456 		bool poll = false;
457 
458 		cnt = min(len - offs, NFC_SRAM_SIZE);
459 
460 		ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
461 		if (ret)
462 			break;
463 
464 		writel(cnt, nfc->regs + NFC_REG_CNT);
465 		tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD;
466 		writel(tmp, nfc->regs + NFC_REG_CMD);
467 
468 		/* Arbitrary limit for polling mode */
469 		if (cnt < 64)
470 			poll = true;
471 
472 		ret = sunxi_nfc_wait_events(nfc, NFC_CMD_INT_FLAG, poll, 0);
473 		if (ret)
474 			break;
475 
476 		if (buf)
477 			memcpy_fromio(buf + offs, nfc->regs + NFC_RAM0_BASE,
478 				      cnt);
479 		offs += cnt;
480 	}
481 }
482 
483 static void sunxi_nfc_write_buf(struct nand_chip *nand, const uint8_t *buf,
484 				int len)
485 {
486 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
487 	struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
488 	int ret;
489 	int cnt;
490 	int offs = 0;
491 	u32 tmp;
492 
493 	while (len > offs) {
494 		bool poll = false;
495 
496 		cnt = min(len - offs, NFC_SRAM_SIZE);
497 
498 		ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
499 		if (ret)
500 			break;
501 
502 		writel(cnt, nfc->regs + NFC_REG_CNT);
503 		memcpy_toio(nfc->regs + NFC_RAM0_BASE, buf + offs, cnt);
504 		tmp = NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
505 		      NFC_ACCESS_DIR;
506 		writel(tmp, nfc->regs + NFC_REG_CMD);
507 
508 		/* Arbitrary limit for polling mode */
509 		if (cnt < 64)
510 			poll = true;
511 
512 		ret = sunxi_nfc_wait_events(nfc, NFC_CMD_INT_FLAG, poll, 0);
513 		if (ret)
514 			break;
515 
516 		offs += cnt;
517 	}
518 }
519 
520 /* These seed values have been extracted from Allwinner's BSP */
521 static const u16 sunxi_nfc_randomizer_page_seeds[] = {
522 	0x2b75, 0x0bd0, 0x5ca3, 0x62d1, 0x1c93, 0x07e9, 0x2162, 0x3a72,
523 	0x0d67, 0x67f9, 0x1be7, 0x077d, 0x032f, 0x0dac, 0x2716, 0x2436,
524 	0x7922, 0x1510, 0x3860, 0x5287, 0x480f, 0x4252, 0x1789, 0x5a2d,
525 	0x2a49, 0x5e10, 0x437f, 0x4b4e, 0x2f45, 0x216e, 0x5cb7, 0x7130,
526 	0x2a3f, 0x60e4, 0x4dc9, 0x0ef0, 0x0f52, 0x1bb9, 0x6211, 0x7a56,
527 	0x226d, 0x4ea7, 0x6f36, 0x3692, 0x38bf, 0x0c62, 0x05eb, 0x4c55,
528 	0x60f4, 0x728c, 0x3b6f, 0x2037, 0x7f69, 0x0936, 0x651a, 0x4ceb,
529 	0x6218, 0x79f3, 0x383f, 0x18d9, 0x4f05, 0x5c82, 0x2912, 0x6f17,
530 	0x6856, 0x5938, 0x1007, 0x61ab, 0x3e7f, 0x57c2, 0x542f, 0x4f62,
531 	0x7454, 0x2eac, 0x7739, 0x42d4, 0x2f90, 0x435a, 0x2e52, 0x2064,
532 	0x637c, 0x66ad, 0x2c90, 0x0bad, 0x759c, 0x0029, 0x0986, 0x7126,
533 	0x1ca7, 0x1605, 0x386a, 0x27f5, 0x1380, 0x6d75, 0x24c3, 0x0f8e,
534 	0x2b7a, 0x1418, 0x1fd1, 0x7dc1, 0x2d8e, 0x43af, 0x2267, 0x7da3,
535 	0x4e3d, 0x1338, 0x50db, 0x454d, 0x764d, 0x40a3, 0x42e6, 0x262b,
536 	0x2d2e, 0x1aea, 0x2e17, 0x173d, 0x3a6e, 0x71bf, 0x25f9, 0x0a5d,
537 	0x7c57, 0x0fbe, 0x46ce, 0x4939, 0x6b17, 0x37bb, 0x3e91, 0x76db,
538 };
539 
540 /*
541  * sunxi_nfc_randomizer_ecc512_seeds and sunxi_nfc_randomizer_ecc1024_seeds
542  * have been generated using
543  * sunxi_nfc_randomizer_step(seed, (step_size * 8) + 15), which is what
544  * the randomizer engine does internally before de/scrambling OOB data.
545  *
546  * Those tables are statically defined to avoid calculating randomizer state
547  * at runtime.
548  */
549 static const u16 sunxi_nfc_randomizer_ecc512_seeds[] = {
550 	0x3346, 0x367f, 0x1f18, 0x769a, 0x4f64, 0x068c, 0x2ef1, 0x6b64,
551 	0x28a9, 0x15d7, 0x30f8, 0x3659, 0x53db, 0x7c5f, 0x71d4, 0x4409,
552 	0x26eb, 0x03cc, 0x655d, 0x47d4, 0x4daa, 0x0877, 0x712d, 0x3617,
553 	0x3264, 0x49aa, 0x7f9e, 0x588e, 0x4fbc, 0x7176, 0x7f91, 0x6c6d,
554 	0x4b95, 0x5fb7, 0x3844, 0x4037, 0x0184, 0x081b, 0x0ee8, 0x5b91,
555 	0x293d, 0x1f71, 0x0e6f, 0x402b, 0x5122, 0x1e52, 0x22be, 0x3d2d,
556 	0x75bc, 0x7c60, 0x6291, 0x1a2f, 0x61d4, 0x74aa, 0x4140, 0x29ab,
557 	0x472d, 0x2852, 0x017e, 0x15e8, 0x5ec2, 0x17cf, 0x7d0f, 0x06b8,
558 	0x117a, 0x6b94, 0x789b, 0x3126, 0x6ac5, 0x5be7, 0x150f, 0x51f8,
559 	0x7889, 0x0aa5, 0x663d, 0x77e8, 0x0b87, 0x3dcb, 0x360d, 0x218b,
560 	0x512f, 0x7dc9, 0x6a4d, 0x630a, 0x3547, 0x1dd2, 0x5aea, 0x69a5,
561 	0x7bfa, 0x5e4f, 0x1519, 0x6430, 0x3a0e, 0x5eb3, 0x5425, 0x0c7a,
562 	0x5540, 0x3670, 0x63c1, 0x31e9, 0x5a39, 0x2de7, 0x5979, 0x2891,
563 	0x1562, 0x014b, 0x5b05, 0x2756, 0x5a34, 0x13aa, 0x6cb5, 0x2c36,
564 	0x5e72, 0x1306, 0x0861, 0x15ef, 0x1ee8, 0x5a37, 0x7ac4, 0x45dd,
565 	0x44c4, 0x7266, 0x2f41, 0x3ccc, 0x045e, 0x7d40, 0x7c66, 0x0fa0,
566 };
567 
568 static const u16 sunxi_nfc_randomizer_ecc1024_seeds[] = {
569 	0x2cf5, 0x35f1, 0x63a4, 0x5274, 0x2bd2, 0x778b, 0x7285, 0x32b6,
570 	0x6a5c, 0x70d6, 0x757d, 0x6769, 0x5375, 0x1e81, 0x0cf3, 0x3982,
571 	0x6787, 0x042a, 0x6c49, 0x1925, 0x56a8, 0x40a9, 0x063e, 0x7bd9,
572 	0x4dbf, 0x55ec, 0x672e, 0x7334, 0x5185, 0x4d00, 0x232a, 0x7e07,
573 	0x445d, 0x6b92, 0x528f, 0x4255, 0x53ba, 0x7d82, 0x2a2e, 0x3a4e,
574 	0x75eb, 0x450c, 0x6844, 0x1b5d, 0x581a, 0x4cc6, 0x0379, 0x37b2,
575 	0x419f, 0x0e92, 0x6b27, 0x5624, 0x01e3, 0x07c1, 0x44a5, 0x130c,
576 	0x13e8, 0x5910, 0x0876, 0x60c5, 0x54e3, 0x5b7f, 0x2269, 0x509f,
577 	0x7665, 0x36fd, 0x3e9a, 0x0579, 0x6295, 0x14ef, 0x0a81, 0x1bcc,
578 	0x4b16, 0x64db, 0x0514, 0x4f07, 0x0591, 0x3576, 0x6853, 0x0d9e,
579 	0x259f, 0x38b7, 0x64fb, 0x3094, 0x4693, 0x6ddd, 0x29bb, 0x0bc8,
580 	0x3f47, 0x490e, 0x0c0e, 0x7933, 0x3c9e, 0x5840, 0x398d, 0x3e68,
581 	0x4af1, 0x71f5, 0x57cf, 0x1121, 0x64eb, 0x3579, 0x15ac, 0x584d,
582 	0x5f2a, 0x47e2, 0x6528, 0x6eac, 0x196e, 0x6b96, 0x0450, 0x0179,
583 	0x609c, 0x06e1, 0x4626, 0x42c7, 0x273e, 0x486f, 0x0705, 0x1601,
584 	0x145b, 0x407e, 0x062b, 0x57a5, 0x53f9, 0x5659, 0x4410, 0x3ccd,
585 };
586 
587 static u16 sunxi_nfc_randomizer_step(u16 state, int count)
588 {
589 	state &= 0x7fff;
590 
591 	/*
592 	 * This loop is just a simple implementation of a Fibonacci LFSR using
593 	 * the x16 + x15 + 1 polynomial.
594 	 */
595 	while (count--)
596 		state = ((state >> 1) |
597 			 (((state ^ (state >> 1)) & 1) << 14)) & 0x7fff;
598 
599 	return state;
600 }
601 
602 static u16 sunxi_nfc_randomizer_state(struct nand_chip *nand, int page,
603 				      bool ecc)
604 {
605 	struct mtd_info *mtd = nand_to_mtd(nand);
606 	const u16 *seeds = sunxi_nfc_randomizer_page_seeds;
607 	int mod = mtd_div_by_ws(mtd->erasesize, mtd);
608 
609 	if (mod > ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds))
610 		mod = ARRAY_SIZE(sunxi_nfc_randomizer_page_seeds);
611 
612 	if (ecc) {
613 		if (mtd->ecc_step_size == 512)
614 			seeds = sunxi_nfc_randomizer_ecc512_seeds;
615 		else
616 			seeds = sunxi_nfc_randomizer_ecc1024_seeds;
617 	}
618 
619 	return seeds[page % mod];
620 }
621 
622 static void sunxi_nfc_randomizer_config(struct nand_chip *nand, int page,
623 					bool ecc)
624 {
625 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
626 	u32 ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL);
627 	u16 state;
628 
629 	if (!(nand->options & NAND_NEED_SCRAMBLING))
630 		return;
631 
632 	ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL);
633 	state = sunxi_nfc_randomizer_state(nand, page, ecc);
634 	ecc_ctl = readl(nfc->regs + NFC_REG_ECC_CTL) & ~NFC_RANDOM_SEED_MSK;
635 	writel(ecc_ctl | NFC_RANDOM_SEED(state), nfc->regs + NFC_REG_ECC_CTL);
636 }
637 
638 static void sunxi_nfc_randomizer_enable(struct nand_chip *nand)
639 {
640 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
641 
642 	if (!(nand->options & NAND_NEED_SCRAMBLING))
643 		return;
644 
645 	writel(readl(nfc->regs + NFC_REG_ECC_CTL) | NFC_RANDOM_EN,
646 	       nfc->regs + NFC_REG_ECC_CTL);
647 }
648 
649 static void sunxi_nfc_randomizer_disable(struct nand_chip *nand)
650 {
651 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
652 
653 	if (!(nand->options & NAND_NEED_SCRAMBLING))
654 		return;
655 
656 	writel(readl(nfc->regs + NFC_REG_ECC_CTL) & ~NFC_RANDOM_EN,
657 	       nfc->regs + NFC_REG_ECC_CTL);
658 }
659 
660 static void sunxi_nfc_randomize_bbm(struct nand_chip *nand, int page, u8 *bbm)
661 {
662 	u16 state = sunxi_nfc_randomizer_state(nand, page, true);
663 
664 	bbm[0] ^= state;
665 	bbm[1] ^= sunxi_nfc_randomizer_step(state, 8);
666 }
667 
668 static void sunxi_nfc_randomizer_write_buf(struct nand_chip *nand,
669 					   const uint8_t *buf, int len,
670 					   bool ecc, int page)
671 {
672 	sunxi_nfc_randomizer_config(nand, page, ecc);
673 	sunxi_nfc_randomizer_enable(nand);
674 	sunxi_nfc_write_buf(nand, buf, len);
675 	sunxi_nfc_randomizer_disable(nand);
676 }
677 
678 static void sunxi_nfc_randomizer_read_buf(struct nand_chip *nand, uint8_t *buf,
679 					  int len, bool ecc, int page)
680 {
681 	sunxi_nfc_randomizer_config(nand, page, ecc);
682 	sunxi_nfc_randomizer_enable(nand);
683 	sunxi_nfc_read_buf(nand, buf, len);
684 	sunxi_nfc_randomizer_disable(nand);
685 }
686 
687 static void sunxi_nfc_hw_ecc_enable(struct nand_chip *nand)
688 {
689 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
690 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
691 
692 	writel(sunxi_nand->ecc.ecc_ctl, nfc->regs + NFC_REG_ECC_CTL);
693 }
694 
695 static void sunxi_nfc_hw_ecc_disable(struct nand_chip *nand)
696 {
697 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
698 
699 	writel(0, nfc->regs + NFC_REG_ECC_CTL);
700 }
701 
702 static inline void sunxi_nfc_user_data_to_buf(u32 user_data, u8 *buf)
703 {
704 	buf[0] = user_data;
705 	buf[1] = user_data >> 8;
706 	buf[2] = user_data >> 16;
707 	buf[3] = user_data >> 24;
708 }
709 
710 static inline u32 sunxi_nfc_buf_to_user_data(const u8 *buf)
711 {
712 	return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
713 }
714 
715 static void sunxi_nfc_hw_ecc_get_prot_oob_bytes(struct nand_chip *nand, u8 *oob,
716 						int step, bool bbm, int page)
717 {
718 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
719 
720 	sunxi_nfc_user_data_to_buf(readl(nfc->regs + NFC_REG_USER_DATA(step)),
721 				   oob);
722 
723 	/* De-randomize the Bad Block Marker. */
724 	if (bbm && (nand->options & NAND_NEED_SCRAMBLING))
725 		sunxi_nfc_randomize_bbm(nand, page, oob);
726 }
727 
728 static void sunxi_nfc_hw_ecc_set_prot_oob_bytes(struct nand_chip *nand,
729 						const u8 *oob, int step,
730 						bool bbm, int page)
731 {
732 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
733 	u8 user_data[4];
734 
735 	/* Randomize the Bad Block Marker. */
736 	if (bbm && (nand->options & NAND_NEED_SCRAMBLING)) {
737 		memcpy(user_data, oob, sizeof(user_data));
738 		sunxi_nfc_randomize_bbm(nand, page, user_data);
739 		oob = user_data;
740 	}
741 
742 	writel(sunxi_nfc_buf_to_user_data(oob),
743 	       nfc->regs + NFC_REG_USER_DATA(step));
744 }
745 
746 static void sunxi_nfc_hw_ecc_update_stats(struct nand_chip *nand,
747 					  unsigned int *max_bitflips, int ret)
748 {
749 	struct mtd_info *mtd = nand_to_mtd(nand);
750 
751 	if (ret < 0) {
752 		mtd->ecc_stats.failed++;
753 	} else {
754 		mtd->ecc_stats.corrected += ret;
755 		*max_bitflips = max_t(unsigned int, *max_bitflips, ret);
756 	}
757 }
758 
759 static int sunxi_nfc_hw_ecc_correct(struct nand_chip *nand, u8 *data, u8 *oob,
760 				    int step, u32 status, bool *erased)
761 {
762 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
763 	struct nand_ecc_ctrl *ecc = &nand->ecc;
764 	u32 tmp;
765 
766 	*erased = false;
767 
768 	if (status & NFC_ECC_ERR(step))
769 		return -EBADMSG;
770 
771 	if (status & NFC_ECC_PAT_FOUND(step)) {
772 		u8 pattern;
773 
774 		if (unlikely(!(readl(nfc->regs + NFC_REG_PAT_ID) & 0x1))) {
775 			pattern = 0x0;
776 		} else {
777 			pattern = 0xff;
778 			*erased = true;
779 		}
780 
781 		if (data)
782 			memset(data, pattern, ecc->size);
783 
784 		if (oob)
785 			memset(oob, pattern, ecc->bytes + 4);
786 
787 		return 0;
788 	}
789 
790 	tmp = readl(nfc->regs + NFC_REG_ECC_ERR_CNT(step));
791 
792 	return NFC_ECC_ERR_CNT(step, tmp);
793 }
794 
795 static int sunxi_nfc_hw_ecc_read_chunk(struct nand_chip *nand,
796 				       u8 *data, int data_off,
797 				       u8 *oob, int oob_off,
798 				       int *cur_off,
799 				       unsigned int *max_bitflips,
800 				       bool bbm, bool oob_required, int page)
801 {
802 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
803 	struct nand_ecc_ctrl *ecc = &nand->ecc;
804 	int raw_mode = 0;
805 	bool erased;
806 	int ret;
807 
808 	if (*cur_off != data_off)
809 		nand_change_read_column_op(nand, data_off, NULL, 0, false);
810 
811 	sunxi_nfc_randomizer_read_buf(nand, NULL, ecc->size, false, page);
812 
813 	if (data_off + ecc->size != oob_off)
814 		nand_change_read_column_op(nand, oob_off, NULL, 0, false);
815 
816 	ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
817 	if (ret)
818 		return ret;
819 
820 	sunxi_nfc_randomizer_enable(nand);
821 	writel(NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD | NFC_ECC_OP,
822 	       nfc->regs + NFC_REG_CMD);
823 
824 	ret = sunxi_nfc_wait_events(nfc, NFC_CMD_INT_FLAG, false, 0);
825 	sunxi_nfc_randomizer_disable(nand);
826 	if (ret)
827 		return ret;
828 
829 	*cur_off = oob_off + ecc->bytes + 4;
830 
831 	ret = sunxi_nfc_hw_ecc_correct(nand, data, oob_required ? oob : NULL, 0,
832 				       readl(nfc->regs + NFC_REG_ECC_ST),
833 				       &erased);
834 	if (erased)
835 		return 1;
836 
837 	if (ret < 0) {
838 		/*
839 		 * Re-read the data with the randomizer disabled to identify
840 		 * bitflips in erased pages.
841 		 */
842 		if (nand->options & NAND_NEED_SCRAMBLING)
843 			nand_change_read_column_op(nand, data_off, data,
844 						   ecc->size, false);
845 		else
846 			memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE,
847 				      ecc->size);
848 
849 		nand_change_read_column_op(nand, oob_off, oob, ecc->bytes + 4,
850 					   false);
851 
852 		ret = nand_check_erased_ecc_chunk(data,	ecc->size,
853 						  oob, ecc->bytes + 4,
854 						  NULL, 0, ecc->strength);
855 		if (ret >= 0)
856 			raw_mode = 1;
857 	} else {
858 		memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE, ecc->size);
859 
860 		if (oob_required) {
861 			nand_change_read_column_op(nand, oob_off, NULL, 0,
862 						   false);
863 			sunxi_nfc_randomizer_read_buf(nand, oob, ecc->bytes + 4,
864 						      true, page);
865 
866 			sunxi_nfc_hw_ecc_get_prot_oob_bytes(nand, oob, 0,
867 							    bbm, page);
868 		}
869 	}
870 
871 	sunxi_nfc_hw_ecc_update_stats(nand, max_bitflips, ret);
872 
873 	return raw_mode;
874 }
875 
876 static void sunxi_nfc_hw_ecc_read_extra_oob(struct nand_chip *nand,
877 					    u8 *oob, int *cur_off,
878 					    bool randomize, int page)
879 {
880 	struct mtd_info *mtd = nand_to_mtd(nand);
881 	struct nand_ecc_ctrl *ecc = &nand->ecc;
882 	int offset = ((ecc->bytes + 4) * ecc->steps);
883 	int len = mtd->oobsize - offset;
884 
885 	if (len <= 0)
886 		return;
887 
888 	if (!cur_off || *cur_off != offset)
889 		nand_change_read_column_op(nand, mtd->writesize, NULL, 0,
890 					   false);
891 
892 	if (!randomize)
893 		sunxi_nfc_read_buf(nand, oob + offset, len);
894 	else
895 		sunxi_nfc_randomizer_read_buf(nand, oob + offset, len,
896 					      false, page);
897 
898 	if (cur_off)
899 		*cur_off = mtd->oobsize + mtd->writesize;
900 }
901 
902 static int sunxi_nfc_hw_ecc_read_chunks_dma(struct nand_chip *nand, uint8_t *buf,
903 					    int oob_required, int page,
904 					    int nchunks)
905 {
906 	bool randomized = nand->options & NAND_NEED_SCRAMBLING;
907 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
908 	struct mtd_info *mtd = nand_to_mtd(nand);
909 	struct nand_ecc_ctrl *ecc = &nand->ecc;
910 	unsigned int max_bitflips = 0;
911 	int ret, i, raw_mode = 0;
912 	struct scatterlist sg;
913 	u32 status, wait;
914 
915 	ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
916 	if (ret)
917 		return ret;
918 
919 	ret = sunxi_nfc_dma_op_prepare(nfc, buf, ecc->size, nchunks,
920 				       DMA_FROM_DEVICE, &sg);
921 	if (ret)
922 		return ret;
923 
924 	sunxi_nfc_hw_ecc_enable(nand);
925 	sunxi_nfc_randomizer_config(nand, page, false);
926 	sunxi_nfc_randomizer_enable(nand);
927 
928 	writel((NAND_CMD_RNDOUTSTART << 16) | (NAND_CMD_RNDOUT << 8) |
929 	       NAND_CMD_READSTART, nfc->regs + NFC_REG_RCMD_SET);
930 
931 	wait = NFC_CMD_INT_FLAG;
932 
933 	if (nfc->caps->has_mdma)
934 		wait |= NFC_DMA_INT_FLAG;
935 	else
936 		dma_async_issue_pending(nfc->dmac);
937 
938 	writel(NFC_PAGE_OP | NFC_DATA_SWAP_METHOD | NFC_DATA_TRANS,
939 	       nfc->regs + NFC_REG_CMD);
940 
941 	ret = sunxi_nfc_wait_events(nfc, wait, false, 0);
942 	if (ret && !nfc->caps->has_mdma)
943 		dmaengine_terminate_all(nfc->dmac);
944 
945 	sunxi_nfc_randomizer_disable(nand);
946 	sunxi_nfc_hw_ecc_disable(nand);
947 
948 	sunxi_nfc_dma_op_cleanup(nfc, DMA_FROM_DEVICE, &sg);
949 
950 	if (ret)
951 		return ret;
952 
953 	status = readl(nfc->regs + NFC_REG_ECC_ST);
954 
955 	for (i = 0; i < nchunks; i++) {
956 		int data_off = i * ecc->size;
957 		int oob_off = i * (ecc->bytes + 4);
958 		u8 *data = buf + data_off;
959 		u8 *oob = nand->oob_poi + oob_off;
960 		bool erased;
961 
962 		ret = sunxi_nfc_hw_ecc_correct(nand, randomized ? data : NULL,
963 					       oob_required ? oob : NULL,
964 					       i, status, &erased);
965 
966 		/* ECC errors are handled in the second loop. */
967 		if (ret < 0)
968 			continue;
969 
970 		if (oob_required && !erased) {
971 			/* TODO: use DMA to retrieve OOB */
972 			nand_change_read_column_op(nand,
973 						   mtd->writesize + oob_off,
974 						   oob, ecc->bytes + 4, false);
975 
976 			sunxi_nfc_hw_ecc_get_prot_oob_bytes(nand, oob, i,
977 							    !i, page);
978 		}
979 
980 		if (erased)
981 			raw_mode = 1;
982 
983 		sunxi_nfc_hw_ecc_update_stats(nand, &max_bitflips, ret);
984 	}
985 
986 	if (status & NFC_ECC_ERR_MSK) {
987 		for (i = 0; i < nchunks; i++) {
988 			int data_off = i * ecc->size;
989 			int oob_off = i * (ecc->bytes + 4);
990 			u8 *data = buf + data_off;
991 			u8 *oob = nand->oob_poi + oob_off;
992 
993 			if (!(status & NFC_ECC_ERR(i)))
994 				continue;
995 
996 			/*
997 			 * Re-read the data with the randomizer disabled to
998 			 * identify bitflips in erased pages.
999 			 * TODO: use DMA to read page in raw mode
1000 			 */
1001 			if (randomized)
1002 				nand_change_read_column_op(nand, data_off,
1003 							   data, ecc->size,
1004 							   false);
1005 
1006 			/* TODO: use DMA to retrieve OOB */
1007 			nand_change_read_column_op(nand,
1008 						   mtd->writesize + oob_off,
1009 						   oob, ecc->bytes + 4, false);
1010 
1011 			ret = nand_check_erased_ecc_chunk(data,	ecc->size,
1012 							  oob, ecc->bytes + 4,
1013 							  NULL, 0,
1014 							  ecc->strength);
1015 			if (ret >= 0)
1016 				raw_mode = 1;
1017 
1018 			sunxi_nfc_hw_ecc_update_stats(nand, &max_bitflips, ret);
1019 		}
1020 	}
1021 
1022 	if (oob_required)
1023 		sunxi_nfc_hw_ecc_read_extra_oob(nand, nand->oob_poi,
1024 						NULL, !raw_mode,
1025 						page);
1026 
1027 	return max_bitflips;
1028 }
1029 
1030 static int sunxi_nfc_hw_ecc_write_chunk(struct nand_chip *nand,
1031 					const u8 *data, int data_off,
1032 					const u8 *oob, int oob_off,
1033 					int *cur_off, bool bbm,
1034 					int page)
1035 {
1036 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
1037 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1038 	int ret;
1039 
1040 	if (data_off != *cur_off)
1041 		nand_change_write_column_op(nand, data_off, NULL, 0, false);
1042 
1043 	sunxi_nfc_randomizer_write_buf(nand, data, ecc->size, false, page);
1044 
1045 	if (data_off + ecc->size != oob_off)
1046 		nand_change_write_column_op(nand, oob_off, NULL, 0, false);
1047 
1048 	ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
1049 	if (ret)
1050 		return ret;
1051 
1052 	sunxi_nfc_randomizer_enable(nand);
1053 	sunxi_nfc_hw_ecc_set_prot_oob_bytes(nand, oob, 0, bbm, page);
1054 
1055 	writel(NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
1056 	       NFC_ACCESS_DIR | NFC_ECC_OP,
1057 	       nfc->regs + NFC_REG_CMD);
1058 
1059 	ret = sunxi_nfc_wait_events(nfc, NFC_CMD_INT_FLAG, false, 0);
1060 	sunxi_nfc_randomizer_disable(nand);
1061 	if (ret)
1062 		return ret;
1063 
1064 	*cur_off = oob_off + ecc->bytes + 4;
1065 
1066 	return 0;
1067 }
1068 
1069 static void sunxi_nfc_hw_ecc_write_extra_oob(struct nand_chip *nand,
1070 					     u8 *oob, int *cur_off,
1071 					     int page)
1072 {
1073 	struct mtd_info *mtd = nand_to_mtd(nand);
1074 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1075 	int offset = ((ecc->bytes + 4) * ecc->steps);
1076 	int len = mtd->oobsize - offset;
1077 
1078 	if (len <= 0)
1079 		return;
1080 
1081 	if (!cur_off || *cur_off != offset)
1082 		nand_change_write_column_op(nand, offset + mtd->writesize,
1083 					    NULL, 0, false);
1084 
1085 	sunxi_nfc_randomizer_write_buf(nand, oob + offset, len, false, page);
1086 
1087 	if (cur_off)
1088 		*cur_off = mtd->oobsize + mtd->writesize;
1089 }
1090 
1091 static int sunxi_nfc_hw_ecc_read_page(struct nand_chip *nand, uint8_t *buf,
1092 				      int oob_required, int page)
1093 {
1094 	struct mtd_info *mtd = nand_to_mtd(nand);
1095 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1096 	unsigned int max_bitflips = 0;
1097 	int ret, i, cur_off = 0;
1098 	bool raw_mode = false;
1099 
1100 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1101 
1102 	nand_read_page_op(nand, page, 0, NULL, 0);
1103 
1104 	sunxi_nfc_hw_ecc_enable(nand);
1105 
1106 	for (i = 0; i < ecc->steps; i++) {
1107 		int data_off = i * ecc->size;
1108 		int oob_off = i * (ecc->bytes + 4);
1109 		u8 *data = buf + data_off;
1110 		u8 *oob = nand->oob_poi + oob_off;
1111 
1112 		ret = sunxi_nfc_hw_ecc_read_chunk(nand, data, data_off, oob,
1113 						  oob_off + mtd->writesize,
1114 						  &cur_off, &max_bitflips,
1115 						  !i, oob_required, page);
1116 		if (ret < 0)
1117 			return ret;
1118 		else if (ret)
1119 			raw_mode = true;
1120 	}
1121 
1122 	if (oob_required)
1123 		sunxi_nfc_hw_ecc_read_extra_oob(nand, nand->oob_poi, &cur_off,
1124 						!raw_mode, page);
1125 
1126 	sunxi_nfc_hw_ecc_disable(nand);
1127 
1128 	return max_bitflips;
1129 }
1130 
1131 static int sunxi_nfc_hw_ecc_read_page_dma(struct nand_chip *nand, u8 *buf,
1132 					  int oob_required, int page)
1133 {
1134 	int ret;
1135 
1136 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1137 
1138 	nand_read_page_op(nand, page, 0, NULL, 0);
1139 
1140 	ret = sunxi_nfc_hw_ecc_read_chunks_dma(nand, buf, oob_required, page,
1141 					       nand->ecc.steps);
1142 	if (ret >= 0)
1143 		return ret;
1144 
1145 	/* Fallback to PIO mode */
1146 	return sunxi_nfc_hw_ecc_read_page(nand, buf, oob_required, page);
1147 }
1148 
1149 static int sunxi_nfc_hw_ecc_read_subpage(struct nand_chip *nand,
1150 					 u32 data_offs, u32 readlen,
1151 					 u8 *bufpoi, int page)
1152 {
1153 	struct mtd_info *mtd = nand_to_mtd(nand);
1154 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1155 	int ret, i, cur_off = 0;
1156 	unsigned int max_bitflips = 0;
1157 
1158 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1159 
1160 	nand_read_page_op(nand, page, 0, NULL, 0);
1161 
1162 	sunxi_nfc_hw_ecc_enable(nand);
1163 
1164 	for (i = data_offs / ecc->size;
1165 	     i < DIV_ROUND_UP(data_offs + readlen, ecc->size); i++) {
1166 		int data_off = i * ecc->size;
1167 		int oob_off = i * (ecc->bytes + 4);
1168 		u8 *data = bufpoi + data_off;
1169 		u8 *oob = nand->oob_poi + oob_off;
1170 
1171 		ret = sunxi_nfc_hw_ecc_read_chunk(nand, data, data_off,
1172 						  oob,
1173 						  oob_off + mtd->writesize,
1174 						  &cur_off, &max_bitflips, !i,
1175 						  false, page);
1176 		if (ret < 0)
1177 			return ret;
1178 	}
1179 
1180 	sunxi_nfc_hw_ecc_disable(nand);
1181 
1182 	return max_bitflips;
1183 }
1184 
1185 static int sunxi_nfc_hw_ecc_read_subpage_dma(struct nand_chip *nand,
1186 					     u32 data_offs, u32 readlen,
1187 					     u8 *buf, int page)
1188 {
1189 	int nchunks = DIV_ROUND_UP(data_offs + readlen, nand->ecc.size);
1190 	int ret;
1191 
1192 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1193 
1194 	nand_read_page_op(nand, page, 0, NULL, 0);
1195 
1196 	ret = sunxi_nfc_hw_ecc_read_chunks_dma(nand, buf, false, page, nchunks);
1197 	if (ret >= 0)
1198 		return ret;
1199 
1200 	/* Fallback to PIO mode */
1201 	return sunxi_nfc_hw_ecc_read_subpage(nand, data_offs, readlen,
1202 					     buf, page);
1203 }
1204 
1205 static int sunxi_nfc_hw_ecc_write_page(struct nand_chip *nand,
1206 				       const uint8_t *buf, int oob_required,
1207 				       int page)
1208 {
1209 	struct mtd_info *mtd = nand_to_mtd(nand);
1210 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1211 	int ret, i, cur_off = 0;
1212 
1213 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1214 
1215 	nand_prog_page_begin_op(nand, page, 0, NULL, 0);
1216 
1217 	sunxi_nfc_hw_ecc_enable(nand);
1218 
1219 	for (i = 0; i < ecc->steps; i++) {
1220 		int data_off = i * ecc->size;
1221 		int oob_off = i * (ecc->bytes + 4);
1222 		const u8 *data = buf + data_off;
1223 		const u8 *oob = nand->oob_poi + oob_off;
1224 
1225 		ret = sunxi_nfc_hw_ecc_write_chunk(nand, data, data_off, oob,
1226 						   oob_off + mtd->writesize,
1227 						   &cur_off, !i, page);
1228 		if (ret)
1229 			return ret;
1230 	}
1231 
1232 	if (oob_required || (nand->options & NAND_NEED_SCRAMBLING))
1233 		sunxi_nfc_hw_ecc_write_extra_oob(nand, nand->oob_poi,
1234 						 &cur_off, page);
1235 
1236 	sunxi_nfc_hw_ecc_disable(nand);
1237 
1238 	return nand_prog_page_end_op(nand);
1239 }
1240 
1241 static int sunxi_nfc_hw_ecc_write_subpage(struct nand_chip *nand,
1242 					  u32 data_offs, u32 data_len,
1243 					  const u8 *buf, int oob_required,
1244 					  int page)
1245 {
1246 	struct mtd_info *mtd = nand_to_mtd(nand);
1247 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1248 	int ret, i, cur_off = 0;
1249 
1250 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1251 
1252 	nand_prog_page_begin_op(nand, page, 0, NULL, 0);
1253 
1254 	sunxi_nfc_hw_ecc_enable(nand);
1255 
1256 	for (i = data_offs / ecc->size;
1257 	     i < DIV_ROUND_UP(data_offs + data_len, ecc->size); i++) {
1258 		int data_off = i * ecc->size;
1259 		int oob_off = i * (ecc->bytes + 4);
1260 		const u8 *data = buf + data_off;
1261 		const u8 *oob = nand->oob_poi + oob_off;
1262 
1263 		ret = sunxi_nfc_hw_ecc_write_chunk(nand, data, data_off, oob,
1264 						   oob_off + mtd->writesize,
1265 						   &cur_off, !i, page);
1266 		if (ret)
1267 			return ret;
1268 	}
1269 
1270 	sunxi_nfc_hw_ecc_disable(nand);
1271 
1272 	return nand_prog_page_end_op(nand);
1273 }
1274 
1275 static int sunxi_nfc_hw_ecc_write_page_dma(struct nand_chip *nand,
1276 					   const u8 *buf,
1277 					   int oob_required,
1278 					   int page)
1279 {
1280 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
1281 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1282 	struct scatterlist sg;
1283 	u32 wait;
1284 	int ret, i;
1285 
1286 	sunxi_nfc_select_chip(nand, nand->cur_cs);
1287 
1288 	ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
1289 	if (ret)
1290 		return ret;
1291 
1292 	ret = sunxi_nfc_dma_op_prepare(nfc, buf, ecc->size, ecc->steps,
1293 				       DMA_TO_DEVICE, &sg);
1294 	if (ret)
1295 		goto pio_fallback;
1296 
1297 	for (i = 0; i < ecc->steps; i++) {
1298 		const u8 *oob = nand->oob_poi + (i * (ecc->bytes + 4));
1299 
1300 		sunxi_nfc_hw_ecc_set_prot_oob_bytes(nand, oob, i, !i, page);
1301 	}
1302 
1303 	nand_prog_page_begin_op(nand, page, 0, NULL, 0);
1304 
1305 	sunxi_nfc_hw_ecc_enable(nand);
1306 	sunxi_nfc_randomizer_config(nand, page, false);
1307 	sunxi_nfc_randomizer_enable(nand);
1308 
1309 	writel((NAND_CMD_RNDIN << 8) | NAND_CMD_PAGEPROG,
1310 	       nfc->regs + NFC_REG_WCMD_SET);
1311 
1312 	wait = NFC_CMD_INT_FLAG;
1313 
1314 	if (nfc->caps->has_mdma)
1315 		wait |= NFC_DMA_INT_FLAG;
1316 	else
1317 		dma_async_issue_pending(nfc->dmac);
1318 
1319 	writel(NFC_PAGE_OP | NFC_DATA_SWAP_METHOD |
1320 	       NFC_DATA_TRANS | NFC_ACCESS_DIR,
1321 	       nfc->regs + NFC_REG_CMD);
1322 
1323 	ret = sunxi_nfc_wait_events(nfc, wait, false, 0);
1324 	if (ret && !nfc->caps->has_mdma)
1325 		dmaengine_terminate_all(nfc->dmac);
1326 
1327 	sunxi_nfc_randomizer_disable(nand);
1328 	sunxi_nfc_hw_ecc_disable(nand);
1329 
1330 	sunxi_nfc_dma_op_cleanup(nfc, DMA_TO_DEVICE, &sg);
1331 
1332 	if (ret)
1333 		return ret;
1334 
1335 	if (oob_required || (nand->options & NAND_NEED_SCRAMBLING))
1336 		/* TODO: use DMA to transfer extra OOB bytes ? */
1337 		sunxi_nfc_hw_ecc_write_extra_oob(nand, nand->oob_poi,
1338 						 NULL, page);
1339 
1340 	return nand_prog_page_end_op(nand);
1341 
1342 pio_fallback:
1343 	return sunxi_nfc_hw_ecc_write_page(nand, buf, oob_required, page);
1344 }
1345 
1346 static int sunxi_nfc_hw_ecc_read_oob(struct nand_chip *nand, int page)
1347 {
1348 	u8 *buf = nand_get_data_buf(nand);
1349 
1350 	return nand->ecc.read_page(nand, buf, 1, page);
1351 }
1352 
1353 static int sunxi_nfc_hw_ecc_write_oob(struct nand_chip *nand, int page)
1354 {
1355 	struct mtd_info *mtd = nand_to_mtd(nand);
1356 	u8 *buf = nand_get_data_buf(nand);
1357 	int ret;
1358 
1359 	memset(buf, 0xff, mtd->writesize);
1360 	ret = nand->ecc.write_page(nand, buf, 1, page);
1361 	if (ret)
1362 		return ret;
1363 
1364 	/* Send command to program the OOB data */
1365 	return nand_prog_page_end_op(nand);
1366 }
1367 
1368 static const s32 tWB_lut[] = {6, 12, 16, 20};
1369 static const s32 tRHW_lut[] = {4, 8, 12, 20};
1370 
1371 static int _sunxi_nand_lookup_timing(const s32 *lut, int lut_size, u32 duration,
1372 		u32 clk_period)
1373 {
1374 	u32 clk_cycles = DIV_ROUND_UP(duration, clk_period);
1375 	int i;
1376 
1377 	for (i = 0; i < lut_size; i++) {
1378 		if (clk_cycles <= lut[i])
1379 			return i;
1380 	}
1381 
1382 	/* Doesn't fit */
1383 	return -EINVAL;
1384 }
1385 
1386 #define sunxi_nand_lookup_timing(l, p, c) \
1387 			_sunxi_nand_lookup_timing(l, ARRAY_SIZE(l), p, c)
1388 
1389 static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
1390 				     const struct nand_interface_config *conf)
1391 {
1392 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
1393 	struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
1394 	const struct nand_sdr_timings *timings;
1395 	u32 min_clk_period = 0;
1396 	s32 tWB, tADL, tWHR, tRHW, tCAD;
1397 	long real_clk_rate;
1398 
1399 	timings = nand_get_sdr_timings(conf);
1400 	if (IS_ERR(timings))
1401 		return -ENOTSUPP;
1402 
1403 	/* T1 <=> tCLS */
1404 	if (timings->tCLS_min > min_clk_period)
1405 		min_clk_period = timings->tCLS_min;
1406 
1407 	/* T2 <=> tCLH */
1408 	if (timings->tCLH_min > min_clk_period)
1409 		min_clk_period = timings->tCLH_min;
1410 
1411 	/* T3 <=> tCS */
1412 	if (timings->tCS_min > min_clk_period)
1413 		min_clk_period = timings->tCS_min;
1414 
1415 	/* T4 <=> tCH */
1416 	if (timings->tCH_min > min_clk_period)
1417 		min_clk_period = timings->tCH_min;
1418 
1419 	/* T5 <=> tWP */
1420 	if (timings->tWP_min > min_clk_period)
1421 		min_clk_period = timings->tWP_min;
1422 
1423 	/* T6 <=> tWH */
1424 	if (timings->tWH_min > min_clk_period)
1425 		min_clk_period = timings->tWH_min;
1426 
1427 	/* T7 <=> tALS */
1428 	if (timings->tALS_min > min_clk_period)
1429 		min_clk_period = timings->tALS_min;
1430 
1431 	/* T8 <=> tDS */
1432 	if (timings->tDS_min > min_clk_period)
1433 		min_clk_period = timings->tDS_min;
1434 
1435 	/* T9 <=> tDH */
1436 	if (timings->tDH_min > min_clk_period)
1437 		min_clk_period = timings->tDH_min;
1438 
1439 	/* T10 <=> tRR */
1440 	if (timings->tRR_min > (min_clk_period * 3))
1441 		min_clk_period = DIV_ROUND_UP(timings->tRR_min, 3);
1442 
1443 	/* T11 <=> tALH */
1444 	if (timings->tALH_min > min_clk_period)
1445 		min_clk_period = timings->tALH_min;
1446 
1447 	/* T12 <=> tRP */
1448 	if (timings->tRP_min > min_clk_period)
1449 		min_clk_period = timings->tRP_min;
1450 
1451 	/* T13 <=> tREH */
1452 	if (timings->tREH_min > min_clk_period)
1453 		min_clk_period = timings->tREH_min;
1454 
1455 	/* T14 <=> tRC */
1456 	if (timings->tRC_min > (min_clk_period * 2))
1457 		min_clk_period = DIV_ROUND_UP(timings->tRC_min, 2);
1458 
1459 	/* T15 <=> tWC */
1460 	if (timings->tWC_min > (min_clk_period * 2))
1461 		min_clk_period = DIV_ROUND_UP(timings->tWC_min, 2);
1462 
1463 	/* T16 - T19 + tCAD */
1464 	if (timings->tWB_max > (min_clk_period * 20))
1465 		min_clk_period = DIV_ROUND_UP(timings->tWB_max, 20);
1466 
1467 	if (timings->tADL_min > (min_clk_period * 32))
1468 		min_clk_period = DIV_ROUND_UP(timings->tADL_min, 32);
1469 
1470 	if (timings->tWHR_min > (min_clk_period * 32))
1471 		min_clk_period = DIV_ROUND_UP(timings->tWHR_min, 32);
1472 
1473 	if (timings->tRHW_min > (min_clk_period * 20))
1474 		min_clk_period = DIV_ROUND_UP(timings->tRHW_min, 20);
1475 
1476 	/*
1477 	 * In non-EDO, tREA should be less than tRP to guarantee that the
1478 	 * controller does not sample the IO lines too early. Unfortunately,
1479 	 * the sunxi NAND controller does not allow us to have different
1480 	 * values for tRP and tREH (tRP = tREH = tRW / 2).
1481 	 *
1482 	 * We have 2 options to overcome this limitation:
1483 	 *
1484 	 * 1/ Extend tRC to fulfil the tREA <= tRC / 2 constraint
1485 	 * 2/ Use EDO mode (only works if timings->tRLOH > 0)
1486 	 */
1487 	if (timings->tREA_max > min_clk_period && !timings->tRLOH_min)
1488 		min_clk_period = timings->tREA_max;
1489 
1490 	tWB  = sunxi_nand_lookup_timing(tWB_lut, timings->tWB_max,
1491 					min_clk_period);
1492 	if (tWB < 0) {
1493 		dev_err(nfc->dev, "unsupported tWB\n");
1494 		return tWB;
1495 	}
1496 
1497 	tADL = DIV_ROUND_UP(timings->tADL_min, min_clk_period) >> 3;
1498 	if (tADL > 3) {
1499 		dev_err(nfc->dev, "unsupported tADL\n");
1500 		return -EINVAL;
1501 	}
1502 
1503 	tWHR = DIV_ROUND_UP(timings->tWHR_min, min_clk_period) >> 3;
1504 	if (tWHR > 3) {
1505 		dev_err(nfc->dev, "unsupported tWHR\n");
1506 		return -EINVAL;
1507 	}
1508 
1509 	tRHW = sunxi_nand_lookup_timing(tRHW_lut, timings->tRHW_min,
1510 					min_clk_period);
1511 	if (tRHW < 0) {
1512 		dev_err(nfc->dev, "unsupported tRHW\n");
1513 		return tRHW;
1514 	}
1515 
1516 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
1517 		return 0;
1518 
1519 	/*
1520 	 * TODO: according to ONFI specs this value only applies for DDR NAND,
1521 	 * but Allwinner seems to set this to 0x7. Mimic them for now.
1522 	 */
1523 	tCAD = 0x7;
1524 
1525 	/* TODO: A83 has some more bits for CDQSS, CS, CLHZ, CCS, WC */
1526 	sunxi_nand->timing_cfg = NFC_TIMING_CFG(tWB, tADL, tWHR, tRHW, tCAD);
1527 
1528 	/* Convert min_clk_period from picoseconds to nanoseconds */
1529 	min_clk_period = DIV_ROUND_UP(min_clk_period, 1000);
1530 
1531 	/*
1532 	 * Unlike what is stated in Allwinner datasheet, the clk_rate should
1533 	 * be set to (1 / min_clk_period), and not (2 / min_clk_period).
1534 	 * This new formula was verified with a scope and validated by
1535 	 * Allwinner engineers.
1536 	 */
1537 	sunxi_nand->clk_rate = NSEC_PER_SEC / min_clk_period;
1538 	real_clk_rate = clk_round_rate(nfc->mod_clk, sunxi_nand->clk_rate);
1539 	if (real_clk_rate <= 0) {
1540 		dev_err(nfc->dev, "Unable to round clk %lu\n",
1541 			sunxi_nand->clk_rate);
1542 		return -EINVAL;
1543 	}
1544 
1545 	sunxi_nand->timing_ctl = 0;
1546 
1547 	/*
1548 	 * ONFI specification 3.1, paragraph 4.15.2 dictates that EDO data
1549 	 * output cycle timings shall be used if the host drives tRC less than
1550 	 * 30 ns. We should also use EDO mode if tREA is bigger than tRP.
1551 	 */
1552 	min_clk_period = NSEC_PER_SEC / real_clk_rate;
1553 	if (min_clk_period * 2 < 30 || min_clk_period * 1000 < timings->tREA_max)
1554 		sunxi_nand->timing_ctl = NFC_TIMING_CTL_EDO;
1555 
1556 	return 0;
1557 }
1558 
1559 static int sunxi_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
1560 				    struct mtd_oob_region *oobregion)
1561 {
1562 	struct nand_chip *nand = mtd_to_nand(mtd);
1563 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1564 
1565 	if (section >= ecc->steps)
1566 		return -ERANGE;
1567 
1568 	oobregion->offset = section * (ecc->bytes + 4) + 4;
1569 	oobregion->length = ecc->bytes;
1570 
1571 	return 0;
1572 }
1573 
1574 static int sunxi_nand_ooblayout_free(struct mtd_info *mtd, int section,
1575 				     struct mtd_oob_region *oobregion)
1576 {
1577 	struct nand_chip *nand = mtd_to_nand(mtd);
1578 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1579 
1580 	if (section > ecc->steps)
1581 		return -ERANGE;
1582 
1583 	/*
1584 	 * The first 2 bytes are used for BB markers, hence we
1585 	 * only have 2 bytes available in the first user data
1586 	 * section.
1587 	 */
1588 	if (!section && ecc->engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST) {
1589 		oobregion->offset = 2;
1590 		oobregion->length = 2;
1591 
1592 		return 0;
1593 	}
1594 
1595 	/*
1596 	 * The controller does not provide access to OOB bytes
1597 	 * past the end of the ECC data.
1598 	 */
1599 	if (section == ecc->steps && ecc->engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST)
1600 		return -ERANGE;
1601 
1602 	oobregion->offset = section * (ecc->bytes + 4);
1603 
1604 	if (section < ecc->steps)
1605 		oobregion->length = 4;
1606 	else
1607 		oobregion->length = mtd->oobsize - oobregion->offset;
1608 
1609 	return 0;
1610 }
1611 
1612 static const struct mtd_ooblayout_ops sunxi_nand_ooblayout_ops = {
1613 	.ecc = sunxi_nand_ooblayout_ecc,
1614 	.free = sunxi_nand_ooblayout_free,
1615 };
1616 
1617 static int sunxi_nand_hw_ecc_ctrl_init(struct nand_chip *nand,
1618 				       struct nand_ecc_ctrl *ecc,
1619 				       struct device_node *np)
1620 {
1621 	static const u8 strengths[] = { 16, 24, 28, 32, 40, 48, 56, 60, 64 };
1622 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
1623 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
1624 	struct mtd_info *mtd = nand_to_mtd(nand);
1625 	struct nand_device *nanddev = mtd_to_nanddev(mtd);
1626 	int nsectors;
1627 	int i;
1628 
1629 	if (nanddev->ecc.user_conf.flags & NAND_ECC_MAXIMIZE_STRENGTH) {
1630 		int bytes;
1631 
1632 		ecc->size = 1024;
1633 		nsectors = mtd->writesize / ecc->size;
1634 
1635 		/* Reserve 2 bytes for the BBM */
1636 		bytes = (mtd->oobsize - 2) / nsectors;
1637 
1638 		/* 4 non-ECC bytes are added before each ECC bytes section */
1639 		bytes -= 4;
1640 
1641 		/* and bytes has to be even. */
1642 		if (bytes % 2)
1643 			bytes--;
1644 
1645 		ecc->strength = bytes * 8 / fls(8 * ecc->size);
1646 
1647 		for (i = 0; i < ARRAY_SIZE(strengths); i++) {
1648 			if (strengths[i] > ecc->strength)
1649 				break;
1650 		}
1651 
1652 		if (!i)
1653 			ecc->strength = 0;
1654 		else
1655 			ecc->strength = strengths[i - 1];
1656 	}
1657 
1658 	if (ecc->size != 512 && ecc->size != 1024)
1659 		return -EINVAL;
1660 
1661 	/* Prefer 1k ECC chunk over 512 ones */
1662 	if (ecc->size == 512 && mtd->writesize > 512) {
1663 		ecc->size = 1024;
1664 		ecc->strength *= 2;
1665 	}
1666 
1667 	/* Add ECC info retrieval from DT */
1668 	for (i = 0; i < ARRAY_SIZE(strengths); i++) {
1669 		if (ecc->strength <= strengths[i]) {
1670 			/*
1671 			 * Update ecc->strength value with the actual strength
1672 			 * that will be used by the ECC engine.
1673 			 */
1674 			ecc->strength = strengths[i];
1675 			break;
1676 		}
1677 	}
1678 
1679 	if (i >= ARRAY_SIZE(strengths)) {
1680 		dev_err(nfc->dev, "unsupported strength\n");
1681 		return -ENOTSUPP;
1682 	}
1683 
1684 	/* HW ECC always request ECC bytes for 1024 bytes blocks */
1685 	ecc->bytes = DIV_ROUND_UP(ecc->strength * fls(8 * 1024), 8);
1686 
1687 	/* HW ECC always work with even numbers of ECC bytes */
1688 	ecc->bytes = ALIGN(ecc->bytes, 2);
1689 
1690 	nsectors = mtd->writesize / ecc->size;
1691 
1692 	if (mtd->oobsize < ((ecc->bytes + 4) * nsectors))
1693 		return -EINVAL;
1694 
1695 	ecc->read_oob = sunxi_nfc_hw_ecc_read_oob;
1696 	ecc->write_oob = sunxi_nfc_hw_ecc_write_oob;
1697 	mtd_set_ooblayout(mtd, &sunxi_nand_ooblayout_ops);
1698 
1699 	if (nfc->dmac || nfc->caps->has_mdma) {
1700 		ecc->read_page = sunxi_nfc_hw_ecc_read_page_dma;
1701 		ecc->read_subpage = sunxi_nfc_hw_ecc_read_subpage_dma;
1702 		ecc->write_page = sunxi_nfc_hw_ecc_write_page_dma;
1703 		nand->options |= NAND_USES_DMA;
1704 	} else {
1705 		ecc->read_page = sunxi_nfc_hw_ecc_read_page;
1706 		ecc->read_subpage = sunxi_nfc_hw_ecc_read_subpage;
1707 		ecc->write_page = sunxi_nfc_hw_ecc_write_page;
1708 	}
1709 
1710 	/* TODO: support DMA for raw accesses and subpage write */
1711 	ecc->write_subpage = sunxi_nfc_hw_ecc_write_subpage;
1712 	ecc->read_oob_raw = nand_read_oob_std;
1713 	ecc->write_oob_raw = nand_write_oob_std;
1714 
1715 	sunxi_nand->ecc.ecc_ctl = NFC_ECC_MODE(i) | NFC_ECC_EXCEPTION |
1716 				  NFC_ECC_PIPELINE | NFC_ECC_EN;
1717 
1718 	if (ecc->size == 512)
1719 		sunxi_nand->ecc.ecc_ctl |= NFC_ECC_BLOCK_512;
1720 
1721 	return 0;
1722 }
1723 
1724 static int sunxi_nand_attach_chip(struct nand_chip *nand)
1725 {
1726 	const struct nand_ecc_props *requirements =
1727 		nanddev_get_ecc_requirements(&nand->base);
1728 	struct nand_ecc_ctrl *ecc = &nand->ecc;
1729 	struct device_node *np = nand_get_flash_node(nand);
1730 	int ret;
1731 
1732 	if (nand->bbt_options & NAND_BBT_USE_FLASH)
1733 		nand->bbt_options |= NAND_BBT_NO_OOB;
1734 
1735 	if (nand->options & NAND_NEED_SCRAMBLING)
1736 		nand->options |= NAND_NO_SUBPAGE_WRITE;
1737 
1738 	nand->options |= NAND_SUBPAGE_READ;
1739 
1740 	if (!ecc->size) {
1741 		ecc->size = requirements->step_size;
1742 		ecc->strength = requirements->strength;
1743 	}
1744 
1745 	if (!ecc->size || !ecc->strength)
1746 		return -EINVAL;
1747 
1748 	switch (ecc->engine_type) {
1749 	case NAND_ECC_ENGINE_TYPE_ON_HOST:
1750 		ret = sunxi_nand_hw_ecc_ctrl_init(nand, ecc, np);
1751 		if (ret)
1752 			return ret;
1753 		break;
1754 	case NAND_ECC_ENGINE_TYPE_NONE:
1755 	case NAND_ECC_ENGINE_TYPE_SOFT:
1756 		break;
1757 	default:
1758 		return -EINVAL;
1759 	}
1760 
1761 	return 0;
1762 }
1763 
1764 static int sunxi_nfc_exec_subop(struct nand_chip *nand,
1765 				const struct nand_subop *subop)
1766 {
1767 	struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
1768 	u32 cmd = 0, extcmd = 0, cnt = 0, addrs[2] = { };
1769 	unsigned int i, j, remaining, start;
1770 	void *inbuf = NULL;
1771 	int ret;
1772 
1773 	for (i = 0; i < subop->ninstrs; i++) {
1774 		const struct nand_op_instr *instr = &subop->instrs[i];
1775 
1776 		switch (instr->type) {
1777 		case NAND_OP_CMD_INSTR:
1778 			if (cmd & NFC_SEND_CMD1) {
1779 				if (WARN_ON(cmd & NFC_SEND_CMD2))
1780 					return -EINVAL;
1781 
1782 				cmd |= NFC_SEND_CMD2;
1783 				extcmd |= instr->ctx.cmd.opcode;
1784 			} else {
1785 				cmd |= NFC_SEND_CMD1 |
1786 				       NFC_CMD(instr->ctx.cmd.opcode);
1787 			}
1788 			break;
1789 
1790 		case NAND_OP_ADDR_INSTR:
1791 			remaining = nand_subop_get_num_addr_cyc(subop, i);
1792 			start = nand_subop_get_addr_start_off(subop, i);
1793 			for (j = 0; j < 8 && j + start < remaining; j++) {
1794 				u32 addr = instr->ctx.addr.addrs[j + start];
1795 
1796 				addrs[j / 4] |= addr << (j % 4) * 8;
1797 			}
1798 
1799 			if (j)
1800 				cmd |= NFC_SEND_ADR | NFC_ADR_NUM(j);
1801 
1802 			break;
1803 
1804 		case NAND_OP_DATA_IN_INSTR:
1805 		case NAND_OP_DATA_OUT_INSTR:
1806 			start = nand_subop_get_data_start_off(subop, i);
1807 			remaining = nand_subop_get_data_len(subop, i);
1808 			cnt = min_t(u32, remaining, NFC_SRAM_SIZE);
1809 			cmd |= NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD;
1810 
1811 			if (instr->type == NAND_OP_DATA_OUT_INSTR) {
1812 				cmd |= NFC_ACCESS_DIR;
1813 				memcpy_toio(nfc->regs + NFC_RAM0_BASE,
1814 					    instr->ctx.data.buf.out + start,
1815 					    cnt);
1816 			} else {
1817 				inbuf = instr->ctx.data.buf.in + start;
1818 			}
1819 
1820 			break;
1821 
1822 		case NAND_OP_WAITRDY_INSTR:
1823 			cmd |= NFC_WAIT_FLAG;
1824 			break;
1825 		}
1826 	}
1827 
1828 	ret = sunxi_nfc_wait_cmd_fifo_empty(nfc);
1829 	if (ret)
1830 		return ret;
1831 
1832 	if (cmd & NFC_SEND_ADR) {
1833 		writel(addrs[0], nfc->regs + NFC_REG_ADDR_LOW);
1834 		writel(addrs[1], nfc->regs + NFC_REG_ADDR_HIGH);
1835 	}
1836 
1837 	if (cmd & NFC_SEND_CMD2)
1838 		writel(extcmd,
1839 		       nfc->regs +
1840 		       (cmd & NFC_ACCESS_DIR ?
1841 			NFC_REG_WCMD_SET : NFC_REG_RCMD_SET));
1842 
1843 	if (cmd & NFC_DATA_TRANS)
1844 		writel(cnt, nfc->regs + NFC_REG_CNT);
1845 
1846 	writel(cmd, nfc->regs + NFC_REG_CMD);
1847 
1848 	ret = sunxi_nfc_wait_events(nfc, NFC_CMD_INT_FLAG,
1849 				    !(cmd & NFC_WAIT_FLAG) && cnt < 64,
1850 				    0);
1851 	if (ret)
1852 		return ret;
1853 
1854 	if (inbuf)
1855 		memcpy_fromio(inbuf, nfc->regs + NFC_RAM0_BASE, cnt);
1856 
1857 	return 0;
1858 }
1859 
1860 static int sunxi_nfc_soft_waitrdy(struct nand_chip *nand,
1861 				  const struct nand_subop *subop)
1862 {
1863 	return nand_soft_waitrdy(nand,
1864 				 subop->instrs[0].ctx.waitrdy.timeout_ms);
1865 }
1866 
1867 static const struct nand_op_parser sunxi_nfc_op_parser = NAND_OP_PARSER(
1868 	NAND_OP_PARSER_PATTERN(sunxi_nfc_exec_subop,
1869 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1870 			       NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
1871 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1872 			       NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
1873 			       NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, 1024)),
1874 	NAND_OP_PARSER_PATTERN(sunxi_nfc_exec_subop,
1875 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1876 			       NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
1877 			       NAND_OP_PARSER_PAT_DATA_OUT_ELEM(true, 1024),
1878 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1879 			       NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
1880 );
1881 
1882 static const struct nand_op_parser sunxi_nfc_norb_op_parser = NAND_OP_PARSER(
1883 	NAND_OP_PARSER_PATTERN(sunxi_nfc_exec_subop,
1884 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1885 			       NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
1886 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1887 			       NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, 1024)),
1888 	NAND_OP_PARSER_PATTERN(sunxi_nfc_exec_subop,
1889 			       NAND_OP_PARSER_PAT_CMD_ELEM(true),
1890 			       NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
1891 			       NAND_OP_PARSER_PAT_DATA_OUT_ELEM(true, 1024),
1892 			       NAND_OP_PARSER_PAT_CMD_ELEM(true)),
1893 	NAND_OP_PARSER_PATTERN(sunxi_nfc_soft_waitrdy,
1894 			       NAND_OP_PARSER_PAT_WAITRDY_ELEM(false)),
1895 );
1896 
1897 static int sunxi_nfc_exec_op(struct nand_chip *nand,
1898 			     const struct nand_operation *op, bool check_only)
1899 {
1900 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
1901 	const struct nand_op_parser *parser;
1902 
1903 	if (!check_only)
1904 		sunxi_nfc_select_chip(nand, op->cs);
1905 
1906 	if (sunxi_nand->sels[op->cs].rb >= 0)
1907 		parser = &sunxi_nfc_op_parser;
1908 	else
1909 		parser = &sunxi_nfc_norb_op_parser;
1910 
1911 	return nand_op_parser_exec_op(nand, parser, op, check_only);
1912 }
1913 
1914 static const struct nand_controller_ops sunxi_nand_controller_ops = {
1915 	.attach_chip = sunxi_nand_attach_chip,
1916 	.setup_interface = sunxi_nfc_setup_interface,
1917 	.exec_op = sunxi_nfc_exec_op,
1918 };
1919 
1920 static void sunxi_nand_chips_cleanup(struct sunxi_nfc *nfc)
1921 {
1922 	struct sunxi_nand_chip *sunxi_nand;
1923 	struct nand_chip *chip;
1924 	int ret;
1925 
1926 	while (!list_empty(&nfc->chips)) {
1927 		sunxi_nand = list_first_entry(&nfc->chips,
1928 					      struct sunxi_nand_chip,
1929 					      node);
1930 		chip = &sunxi_nand->nand;
1931 		ret = mtd_device_unregister(nand_to_mtd(chip));
1932 		WARN_ON(ret);
1933 		nand_cleanup(chip);
1934 		list_del(&sunxi_nand->node);
1935 	}
1936 }
1937 
1938 static int sunxi_nand_chip_init(struct device *dev, struct sunxi_nfc *nfc,
1939 				struct device_node *np)
1940 {
1941 	struct sunxi_nand_chip *sunxi_nand;
1942 	struct mtd_info *mtd;
1943 	struct nand_chip *nand;
1944 	int nsels;
1945 	int ret;
1946 	int i;
1947 	u32 tmp;
1948 
1949 	if (!of_get_property(np, "reg", &nsels))
1950 		return -EINVAL;
1951 
1952 	nsels /= sizeof(u32);
1953 	if (!nsels) {
1954 		dev_err(dev, "invalid reg property size\n");
1955 		return -EINVAL;
1956 	}
1957 
1958 	sunxi_nand = devm_kzalloc(dev, struct_size(sunxi_nand, sels, nsels),
1959 				  GFP_KERNEL);
1960 	if (!sunxi_nand)
1961 		return -ENOMEM;
1962 
1963 	sunxi_nand->nsels = nsels;
1964 
1965 	for (i = 0; i < nsels; i++) {
1966 		ret = of_property_read_u32_index(np, "reg", i, &tmp);
1967 		if (ret) {
1968 			dev_err(dev, "could not retrieve reg property: %d\n",
1969 				ret);
1970 			return ret;
1971 		}
1972 
1973 		if (tmp > NFC_MAX_CS) {
1974 			dev_err(dev,
1975 				"invalid reg value: %u (max CS = 7)\n",
1976 				tmp);
1977 			return -EINVAL;
1978 		}
1979 
1980 		if (test_and_set_bit(tmp, &nfc->assigned_cs)) {
1981 			dev_err(dev, "CS %d already assigned\n", tmp);
1982 			return -EINVAL;
1983 		}
1984 
1985 		sunxi_nand->sels[i].cs = tmp;
1986 
1987 		if (!of_property_read_u32_index(np, "allwinner,rb", i, &tmp) &&
1988 		    tmp < 2)
1989 			sunxi_nand->sels[i].rb = tmp;
1990 		else
1991 			sunxi_nand->sels[i].rb = -1;
1992 	}
1993 
1994 	nand = &sunxi_nand->nand;
1995 	/* Default tR value specified in the ONFI spec (chapter 4.15.1) */
1996 	nand->controller = &nfc->controller;
1997 	nand->controller->ops = &sunxi_nand_controller_ops;
1998 
1999 	/*
2000 	 * Set the ECC mode to the default value in case nothing is specified
2001 	 * in the DT.
2002 	 */
2003 	nand->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
2004 	nand_set_flash_node(nand, np);
2005 
2006 	mtd = nand_to_mtd(nand);
2007 	mtd->dev.parent = dev;
2008 
2009 	ret = nand_scan(nand, nsels);
2010 	if (ret)
2011 		return ret;
2012 
2013 	ret = mtd_device_register(mtd, NULL, 0);
2014 	if (ret) {
2015 		dev_err(dev, "failed to register mtd device: %d\n", ret);
2016 		nand_cleanup(nand);
2017 		return ret;
2018 	}
2019 
2020 	list_add_tail(&sunxi_nand->node, &nfc->chips);
2021 
2022 	return 0;
2023 }
2024 
2025 static int sunxi_nand_chips_init(struct device *dev, struct sunxi_nfc *nfc)
2026 {
2027 	struct device_node *np = dev->of_node;
2028 	struct device_node *nand_np;
2029 	int ret;
2030 
2031 	for_each_child_of_node(np, nand_np) {
2032 		ret = sunxi_nand_chip_init(dev, nfc, nand_np);
2033 		if (ret) {
2034 			of_node_put(nand_np);
2035 			sunxi_nand_chips_cleanup(nfc);
2036 			return ret;
2037 		}
2038 	}
2039 
2040 	return 0;
2041 }
2042 
2043 static int sunxi_nfc_dma_init(struct sunxi_nfc *nfc, struct resource *r)
2044 {
2045 	int ret;
2046 
2047 	if (nfc->caps->has_mdma)
2048 		return 0;
2049 
2050 	nfc->dmac = dma_request_chan(nfc->dev, "rxtx");
2051 	if (IS_ERR(nfc->dmac)) {
2052 		ret = PTR_ERR(nfc->dmac);
2053 		if (ret == -EPROBE_DEFER)
2054 			return ret;
2055 
2056 		/* Ignore errors to fall back to PIO mode */
2057 		dev_warn(nfc->dev, "failed to request rxtx DMA channel: %d\n", ret);
2058 		nfc->dmac = NULL;
2059 	} else {
2060 		struct dma_slave_config dmac_cfg = { };
2061 
2062 		dmac_cfg.src_addr = r->start + nfc->caps->reg_io_data;
2063 		dmac_cfg.dst_addr = dmac_cfg.src_addr;
2064 		dmac_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
2065 		dmac_cfg.dst_addr_width = dmac_cfg.src_addr_width;
2066 		dmac_cfg.src_maxburst = nfc->caps->dma_maxburst;
2067 		dmac_cfg.dst_maxburst = nfc->caps->dma_maxburst;
2068 		dmaengine_slave_config(nfc->dmac, &dmac_cfg);
2069 	}
2070 	return 0;
2071 }
2072 
2073 static int sunxi_nfc_probe(struct platform_device *pdev)
2074 {
2075 	struct device *dev = &pdev->dev;
2076 	struct resource *r;
2077 	struct sunxi_nfc *nfc;
2078 	int irq;
2079 	int ret;
2080 
2081 	nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
2082 	if (!nfc)
2083 		return -ENOMEM;
2084 
2085 	nfc->dev = dev;
2086 	nand_controller_init(&nfc->controller);
2087 	INIT_LIST_HEAD(&nfc->chips);
2088 
2089 	nfc->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
2090 	if (IS_ERR(nfc->regs))
2091 		return PTR_ERR(nfc->regs);
2092 
2093 	irq = platform_get_irq(pdev, 0);
2094 	if (irq < 0)
2095 		return irq;
2096 
2097 	nfc->ahb_clk = devm_clk_get_enabled(dev, "ahb");
2098 	if (IS_ERR(nfc->ahb_clk)) {
2099 		dev_err(dev, "failed to retrieve ahb clk\n");
2100 		return PTR_ERR(nfc->ahb_clk);
2101 	}
2102 
2103 	nfc->mod_clk = devm_clk_get_enabled(dev, "mod");
2104 	if (IS_ERR(nfc->mod_clk)) {
2105 		dev_err(dev, "failed to retrieve mod clk\n");
2106 		return PTR_ERR(nfc->mod_clk);
2107 	}
2108 
2109 	nfc->reset = devm_reset_control_get_optional_exclusive(dev, "ahb");
2110 	if (IS_ERR(nfc->reset))
2111 		return PTR_ERR(nfc->reset);
2112 
2113 	ret = reset_control_deassert(nfc->reset);
2114 	if (ret) {
2115 		dev_err(dev, "reset err %d\n", ret);
2116 		return ret;
2117 	}
2118 
2119 	nfc->caps = of_device_get_match_data(&pdev->dev);
2120 	if (!nfc->caps) {
2121 		ret = -EINVAL;
2122 		goto out_ahb_reset_reassert;
2123 	}
2124 
2125 	ret = sunxi_nfc_rst(nfc);
2126 	if (ret)
2127 		goto out_ahb_reset_reassert;
2128 
2129 	writel(0, nfc->regs + NFC_REG_INT);
2130 	ret = devm_request_irq(dev, irq, sunxi_nfc_interrupt,
2131 			       0, "sunxi-nand", nfc);
2132 	if (ret)
2133 		goto out_ahb_reset_reassert;
2134 
2135 	ret = sunxi_nfc_dma_init(nfc, r);
2136 
2137 	if (ret)
2138 		goto out_ahb_reset_reassert;
2139 
2140 	platform_set_drvdata(pdev, nfc);
2141 
2142 	ret = sunxi_nand_chips_init(dev, nfc);
2143 	if (ret) {
2144 		dev_err(dev, "failed to init nand chips\n");
2145 		goto out_release_dmac;
2146 	}
2147 
2148 	return 0;
2149 
2150 out_release_dmac:
2151 	if (nfc->dmac)
2152 		dma_release_channel(nfc->dmac);
2153 out_ahb_reset_reassert:
2154 	reset_control_assert(nfc->reset);
2155 
2156 	return ret;
2157 }
2158 
2159 static void sunxi_nfc_remove(struct platform_device *pdev)
2160 {
2161 	struct sunxi_nfc *nfc = platform_get_drvdata(pdev);
2162 
2163 	sunxi_nand_chips_cleanup(nfc);
2164 
2165 	reset_control_assert(nfc->reset);
2166 
2167 	if (nfc->dmac)
2168 		dma_release_channel(nfc->dmac);
2169 }
2170 
2171 static const struct sunxi_nfc_caps sunxi_nfc_a10_caps = {
2172 	.reg_io_data = NFC_REG_A10_IO_DATA,
2173 	.dma_maxburst = 4,
2174 };
2175 
2176 static const struct sunxi_nfc_caps sunxi_nfc_a23_caps = {
2177 	.has_mdma = true,
2178 	.reg_io_data = NFC_REG_A23_IO_DATA,
2179 	.dma_maxburst = 8,
2180 };
2181 
2182 static const struct of_device_id sunxi_nfc_ids[] = {
2183 	{
2184 		.compatible = "allwinner,sun4i-a10-nand",
2185 		.data = &sunxi_nfc_a10_caps,
2186 	},
2187 	{
2188 		.compatible = "allwinner,sun8i-a23-nand-controller",
2189 		.data = &sunxi_nfc_a23_caps,
2190 	},
2191 	{ /* sentinel */ }
2192 };
2193 MODULE_DEVICE_TABLE(of, sunxi_nfc_ids);
2194 
2195 static struct platform_driver sunxi_nfc_driver = {
2196 	.driver = {
2197 		.name = "sunxi_nand",
2198 		.of_match_table = sunxi_nfc_ids,
2199 	},
2200 	.probe = sunxi_nfc_probe,
2201 	.remove_new = sunxi_nfc_remove,
2202 };
2203 module_platform_driver(sunxi_nfc_driver);
2204 
2205 MODULE_LICENSE("GPL");
2206 MODULE_AUTHOR("Boris BREZILLON");
2207 MODULE_DESCRIPTION("Allwinner NAND Flash Controller driver");
2208 MODULE_ALIAS("platform:sunxi_nand");
2209