xref: /openbmc/linux/drivers/mtd/nand/raw/vf610_nfc.c (revision bb3982b4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2009-2015 Freescale Semiconductor, Inc. and others
4  *
5  * Description: MPC5125, VF610, MCF54418 and Kinetis K70 Nand driver.
6  * Jason ported to M54418TWR and MVFA5 (VF610).
7  * Authors: Stefan Agner <stefan.agner@toradex.com>
8  *          Bill Pringlemeir <bpringlemeir@nbsps.com>
9  *          Shaohui Xie <b21989@freescale.com>
10  *          Jason Jin <Jason.jin@freescale.com>
11  *
12  * Based on original driver mpc5121_nfc.c.
13  *
14  * Limitations:
15  * - Untested on MPC5125 and M54418.
16  * - DMA and pipelining not used.
17  * - 2K pages or less.
18  * - HW ECC: Only 2K page with 64+ OOB.
19  * - HW ECC: Only 24 and 32-bit error correction implemented.
20  */
21 
22 #include <linux/module.h>
23 #include <linux/bitops.h>
24 #include <linux/clk.h>
25 #include <linux/delay.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/mtd/mtd.h>
30 #include <linux/mtd/rawnand.h>
31 #include <linux/mtd/partitions.h>
32 #include <linux/of_device.h>
33 #include <linux/platform_device.h>
34 #include <linux/slab.h>
35 #include <linux/swab.h>
36 
37 #define	DRV_NAME		"vf610_nfc"
38 
39 /* Register Offsets */
40 #define NFC_FLASH_CMD1			0x3F00
41 #define NFC_FLASH_CMD2			0x3F04
42 #define NFC_COL_ADDR			0x3F08
43 #define NFC_ROW_ADDR			0x3F0c
44 #define NFC_ROW_ADDR_INC		0x3F14
45 #define NFC_FLASH_STATUS1		0x3F18
46 #define NFC_FLASH_STATUS2		0x3F1c
47 #define NFC_CACHE_SWAP			0x3F28
48 #define NFC_SECTOR_SIZE			0x3F2c
49 #define NFC_FLASH_CONFIG		0x3F30
50 #define NFC_IRQ_STATUS			0x3F38
51 
52 /* Addresses for NFC MAIN RAM BUFFER areas */
53 #define NFC_MAIN_AREA(n)		((n) *  0x1000)
54 
55 #define PAGE_2K				0x0800
56 #define OOB_64				0x0040
57 #define OOB_MAX				0x0100
58 
59 /* NFC_CMD2[CODE] controller cycle bit masks */
60 #define COMMAND_CMD_BYTE1		BIT(14)
61 #define COMMAND_CAR_BYTE1		BIT(13)
62 #define COMMAND_CAR_BYTE2		BIT(12)
63 #define COMMAND_RAR_BYTE1		BIT(11)
64 #define COMMAND_RAR_BYTE2		BIT(10)
65 #define COMMAND_RAR_BYTE3		BIT(9)
66 #define COMMAND_NADDR_BYTES(x)		GENMASK(13, 13 - (x) + 1)
67 #define COMMAND_WRITE_DATA		BIT(8)
68 #define COMMAND_CMD_BYTE2		BIT(7)
69 #define COMMAND_RB_HANDSHAKE		BIT(6)
70 #define COMMAND_READ_DATA		BIT(5)
71 #define COMMAND_CMD_BYTE3		BIT(4)
72 #define COMMAND_READ_STATUS		BIT(3)
73 #define COMMAND_READ_ID			BIT(2)
74 
75 /* NFC ECC mode define */
76 #define ECC_BYPASS			0
77 #define ECC_45_BYTE			6
78 #define ECC_60_BYTE			7
79 
80 /*** Register Mask and bit definitions */
81 
82 /* NFC_FLASH_CMD1 Field */
83 #define CMD_BYTE2_MASK				0xFF000000
84 #define CMD_BYTE2_SHIFT				24
85 
86 /* NFC_FLASH_CM2 Field */
87 #define CMD_BYTE1_MASK				0xFF000000
88 #define CMD_BYTE1_SHIFT				24
89 #define CMD_CODE_MASK				0x00FFFF00
90 #define CMD_CODE_SHIFT				8
91 #define BUFNO_MASK				0x00000006
92 #define BUFNO_SHIFT				1
93 #define START_BIT				BIT(0)
94 
95 /* NFC_COL_ADDR Field */
96 #define COL_ADDR_MASK				0x0000FFFF
97 #define COL_ADDR_SHIFT				0
98 #define COL_ADDR(pos, val)			(((val) & 0xFF) << (8 * (pos)))
99 
100 /* NFC_ROW_ADDR Field */
101 #define ROW_ADDR_MASK				0x00FFFFFF
102 #define ROW_ADDR_SHIFT				0
103 #define ROW_ADDR(pos, val)			(((val) & 0xFF) << (8 * (pos)))
104 
105 #define ROW_ADDR_CHIP_SEL_RB_MASK		0xF0000000
106 #define ROW_ADDR_CHIP_SEL_RB_SHIFT		28
107 #define ROW_ADDR_CHIP_SEL_MASK			0x0F000000
108 #define ROW_ADDR_CHIP_SEL_SHIFT			24
109 
110 /* NFC_FLASH_STATUS2 Field */
111 #define STATUS_BYTE1_MASK			0x000000FF
112 
113 /* NFC_FLASH_CONFIG Field */
114 #define CONFIG_ECC_SRAM_ADDR_MASK		0x7FC00000
115 #define CONFIG_ECC_SRAM_ADDR_SHIFT		22
116 #define CONFIG_ECC_SRAM_REQ_BIT			BIT(21)
117 #define CONFIG_DMA_REQ_BIT			BIT(20)
118 #define CONFIG_ECC_MODE_MASK			0x000E0000
119 #define CONFIG_ECC_MODE_SHIFT			17
120 #define CONFIG_FAST_FLASH_BIT			BIT(16)
121 #define CONFIG_16BIT				BIT(7)
122 #define CONFIG_BOOT_MODE_BIT			BIT(6)
123 #define CONFIG_ADDR_AUTO_INCR_BIT		BIT(5)
124 #define CONFIG_BUFNO_AUTO_INCR_BIT		BIT(4)
125 #define CONFIG_PAGE_CNT_MASK			0xF
126 #define CONFIG_PAGE_CNT_SHIFT			0
127 
128 /* NFC_IRQ_STATUS Field */
129 #define IDLE_IRQ_BIT				BIT(29)
130 #define IDLE_EN_BIT				BIT(20)
131 #define CMD_DONE_CLEAR_BIT			BIT(18)
132 #define IDLE_CLEAR_BIT				BIT(17)
133 
134 /*
135  * ECC status - seems to consume 8 bytes (double word). The documented
136  * status byte is located in the lowest byte of the second word (which is
137  * the 4th or 7th byte depending on endianness).
138  * Calculate an offset to store the ECC status at the end of the buffer.
139  */
140 #define ECC_SRAM_ADDR		(PAGE_2K + OOB_MAX - 8)
141 
142 #define ECC_STATUS		0x4
143 #define ECC_STATUS_MASK		0x80
144 #define ECC_STATUS_ERR_COUNT	0x3F
145 
146 enum vf610_nfc_variant {
147 	NFC_VFC610 = 1,
148 };
149 
150 struct vf610_nfc {
151 	struct nand_controller base;
152 	struct nand_chip chip;
153 	struct device *dev;
154 	void __iomem *regs;
155 	struct completion cmd_done;
156 	/* Status and ID are in alternate locations. */
157 	enum vf610_nfc_variant variant;
158 	struct clk *clk;
159 	/*
160 	 * Indicate that user data is accessed (full page/oob). This is
161 	 * useful to indicate the driver whether to swap byte endianness.
162 	 * See comments in vf610_nfc_rd_from_sram/vf610_nfc_wr_to_sram.
163 	 */
164 	bool data_access;
165 	u32 ecc_mode;
166 };
167 
168 static inline struct vf610_nfc *chip_to_nfc(struct nand_chip *chip)
169 {
170 	return container_of(chip, struct vf610_nfc, chip);
171 }
172 
173 static inline u32 vf610_nfc_read(struct vf610_nfc *nfc, uint reg)
174 {
175 	return readl(nfc->regs + reg);
176 }
177 
178 static inline void vf610_nfc_write(struct vf610_nfc *nfc, uint reg, u32 val)
179 {
180 	writel(val, nfc->regs + reg);
181 }
182 
183 static inline void vf610_nfc_set(struct vf610_nfc *nfc, uint reg, u32 bits)
184 {
185 	vf610_nfc_write(nfc, reg, vf610_nfc_read(nfc, reg) | bits);
186 }
187 
188 static inline void vf610_nfc_clear(struct vf610_nfc *nfc, uint reg, u32 bits)
189 {
190 	vf610_nfc_write(nfc, reg, vf610_nfc_read(nfc, reg) & ~bits);
191 }
192 
193 static inline void vf610_nfc_set_field(struct vf610_nfc *nfc, u32 reg,
194 				       u32 mask, u32 shift, u32 val)
195 {
196 	vf610_nfc_write(nfc, reg,
197 			(vf610_nfc_read(nfc, reg) & (~mask)) | val << shift);
198 }
199 
200 static inline bool vf610_nfc_kernel_is_little_endian(void)
201 {
202 #ifdef __LITTLE_ENDIAN
203 	return true;
204 #else
205 	return false;
206 #endif
207 }
208 
209 /**
210  * Read accessor for internal SRAM buffer
211  * @dst: destination address in regular memory
212  * @src: source address in SRAM buffer
213  * @len: bytes to copy
214  * @fix_endian: Fix endianness if required
215  *
216  * Use this accessor for the internal SRAM buffers. On the ARM
217  * Freescale Vybrid SoC it's known that the driver can treat
218  * the SRAM buffer as if it's memory. Other platform might need
219  * to treat the buffers differently.
220  *
221  * The controller stores bytes from the NAND chip internally in big
222  * endianness. On little endian platforms such as Vybrid this leads
223  * to reversed byte order.
224  * For performance reason (and earlier probably due to unawareness)
225  * the driver avoids correcting endianness where it has control over
226  * write and read side (e.g. page wise data access).
227  */
228 static inline void vf610_nfc_rd_from_sram(void *dst, const void __iomem *src,
229 					  size_t len, bool fix_endian)
230 {
231 	if (vf610_nfc_kernel_is_little_endian() && fix_endian) {
232 		unsigned int i;
233 
234 		for (i = 0; i < len; i += 4) {
235 			u32 val = swab32(__raw_readl(src + i));
236 
237 			memcpy(dst + i, &val, min(sizeof(val), len - i));
238 		}
239 	} else {
240 		memcpy_fromio(dst, src, len);
241 	}
242 }
243 
244 /**
245  * Write accessor for internal SRAM buffer
246  * @dst: destination address in SRAM buffer
247  * @src: source address in regular memory
248  * @len: bytes to copy
249  * @fix_endian: Fix endianness if required
250  *
251  * Use this accessor for the internal SRAM buffers. On the ARM
252  * Freescale Vybrid SoC it's known that the driver can treat
253  * the SRAM buffer as if it's memory. Other platform might need
254  * to treat the buffers differently.
255  *
256  * The controller stores bytes from the NAND chip internally in big
257  * endianness. On little endian platforms such as Vybrid this leads
258  * to reversed byte order.
259  * For performance reason (and earlier probably due to unawareness)
260  * the driver avoids correcting endianness where it has control over
261  * write and read side (e.g. page wise data access).
262  */
263 static inline void vf610_nfc_wr_to_sram(void __iomem *dst, const void *src,
264 					size_t len, bool fix_endian)
265 {
266 	if (vf610_nfc_kernel_is_little_endian() && fix_endian) {
267 		unsigned int i;
268 
269 		for (i = 0; i < len; i += 4) {
270 			u32 val;
271 
272 			memcpy(&val, src + i, min(sizeof(val), len - i));
273 			__raw_writel(swab32(val), dst + i);
274 		}
275 	} else {
276 		memcpy_toio(dst, src, len);
277 	}
278 }
279 
280 /* Clear flags for upcoming command */
281 static inline void vf610_nfc_clear_status(struct vf610_nfc *nfc)
282 {
283 	u32 tmp = vf610_nfc_read(nfc, NFC_IRQ_STATUS);
284 
285 	tmp |= CMD_DONE_CLEAR_BIT | IDLE_CLEAR_BIT;
286 	vf610_nfc_write(nfc, NFC_IRQ_STATUS, tmp);
287 }
288 
289 static void vf610_nfc_done(struct vf610_nfc *nfc)
290 {
291 	unsigned long timeout = msecs_to_jiffies(100);
292 
293 	/*
294 	 * Barrier is needed after this write. This write need
295 	 * to be done before reading the next register the first
296 	 * time.
297 	 * vf610_nfc_set implicates such a barrier by using writel
298 	 * to write to the register.
299 	 */
300 	vf610_nfc_set(nfc, NFC_IRQ_STATUS, IDLE_EN_BIT);
301 	vf610_nfc_set(nfc, NFC_FLASH_CMD2, START_BIT);
302 
303 	if (!wait_for_completion_timeout(&nfc->cmd_done, timeout))
304 		dev_warn(nfc->dev, "Timeout while waiting for BUSY.\n");
305 
306 	vf610_nfc_clear_status(nfc);
307 }
308 
309 static irqreturn_t vf610_nfc_irq(int irq, void *data)
310 {
311 	struct vf610_nfc *nfc = data;
312 
313 	vf610_nfc_clear(nfc, NFC_IRQ_STATUS, IDLE_EN_BIT);
314 	complete(&nfc->cmd_done);
315 
316 	return IRQ_HANDLED;
317 }
318 
319 static inline void vf610_nfc_ecc_mode(struct vf610_nfc *nfc, int ecc_mode)
320 {
321 	vf610_nfc_set_field(nfc, NFC_FLASH_CONFIG,
322 			    CONFIG_ECC_MODE_MASK,
323 			    CONFIG_ECC_MODE_SHIFT, ecc_mode);
324 }
325 
326 static inline void vf610_nfc_transfer_size(struct vf610_nfc *nfc, int size)
327 {
328 	vf610_nfc_write(nfc, NFC_SECTOR_SIZE, size);
329 }
330 
331 static inline void vf610_nfc_run(struct vf610_nfc *nfc, u32 col, u32 row,
332 				 u32 cmd1, u32 cmd2, u32 trfr_sz)
333 {
334 	vf610_nfc_set_field(nfc, NFC_COL_ADDR, COL_ADDR_MASK,
335 			    COL_ADDR_SHIFT, col);
336 
337 	vf610_nfc_set_field(nfc, NFC_ROW_ADDR, ROW_ADDR_MASK,
338 			    ROW_ADDR_SHIFT, row);
339 
340 	vf610_nfc_write(nfc, NFC_SECTOR_SIZE, trfr_sz);
341 	vf610_nfc_write(nfc, NFC_FLASH_CMD1, cmd1);
342 	vf610_nfc_write(nfc, NFC_FLASH_CMD2, cmd2);
343 
344 	dev_dbg(nfc->dev,
345 		"col 0x%04x, row 0x%08x, cmd1 0x%08x, cmd2 0x%08x, len %d\n",
346 		col, row, cmd1, cmd2, trfr_sz);
347 
348 	vf610_nfc_done(nfc);
349 }
350 
351 static inline const struct nand_op_instr *
352 vf610_get_next_instr(const struct nand_subop *subop, int *op_id)
353 {
354 	if (*op_id + 1 >= subop->ninstrs)
355 		return NULL;
356 
357 	(*op_id)++;
358 
359 	return &subop->instrs[*op_id];
360 }
361 
362 static int vf610_nfc_cmd(struct nand_chip *chip,
363 			 const struct nand_subop *subop)
364 {
365 	const struct nand_op_instr *instr;
366 	struct vf610_nfc *nfc = chip_to_nfc(chip);
367 	int op_id = -1, trfr_sz = 0, offset = 0;
368 	u32 col = 0, row = 0, cmd1 = 0, cmd2 = 0, code = 0;
369 	bool force8bit = false;
370 
371 	/*
372 	 * Some ops are optional, but the hardware requires the operations
373 	 * to be in this exact order.
374 	 * The op parser enforces the order and makes sure that there isn't
375 	 * a read and write element in a single operation.
376 	 */
377 	instr = vf610_get_next_instr(subop, &op_id);
378 	if (!instr)
379 		return -EINVAL;
380 
381 	if (instr && instr->type == NAND_OP_CMD_INSTR) {
382 		cmd2 |= instr->ctx.cmd.opcode << CMD_BYTE1_SHIFT;
383 		code |= COMMAND_CMD_BYTE1;
384 
385 		instr = vf610_get_next_instr(subop, &op_id);
386 	}
387 
388 	if (instr && instr->type == NAND_OP_ADDR_INSTR) {
389 		int naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
390 		int i = nand_subop_get_addr_start_off(subop, op_id);
391 
392 		for (; i < naddrs; i++) {
393 			u8 val = instr->ctx.addr.addrs[i];
394 
395 			if (i < 2)
396 				col |= COL_ADDR(i, val);
397 			else
398 				row |= ROW_ADDR(i - 2, val);
399 		}
400 		code |= COMMAND_NADDR_BYTES(naddrs);
401 
402 		instr = vf610_get_next_instr(subop, &op_id);
403 	}
404 
405 	if (instr && instr->type == NAND_OP_DATA_OUT_INSTR) {
406 		trfr_sz = nand_subop_get_data_len(subop, op_id);
407 		offset = nand_subop_get_data_start_off(subop, op_id);
408 		force8bit = instr->ctx.data.force_8bit;
409 
410 		/*
411 		 * Don't fix endianness on page access for historical reasons.
412 		 * See comment in vf610_nfc_wr_to_sram
413 		 */
414 		vf610_nfc_wr_to_sram(nfc->regs + NFC_MAIN_AREA(0) + offset,
415 				     instr->ctx.data.buf.out + offset,
416 				     trfr_sz, !nfc->data_access);
417 		code |= COMMAND_WRITE_DATA;
418 
419 		instr = vf610_get_next_instr(subop, &op_id);
420 	}
421 
422 	if (instr && instr->type == NAND_OP_CMD_INSTR) {
423 		cmd1 |= instr->ctx.cmd.opcode << CMD_BYTE2_SHIFT;
424 		code |= COMMAND_CMD_BYTE2;
425 
426 		instr = vf610_get_next_instr(subop, &op_id);
427 	}
428 
429 	if (instr && instr->type == NAND_OP_WAITRDY_INSTR) {
430 		code |= COMMAND_RB_HANDSHAKE;
431 
432 		instr = vf610_get_next_instr(subop, &op_id);
433 	}
434 
435 	if (instr && instr->type == NAND_OP_DATA_IN_INSTR) {
436 		trfr_sz = nand_subop_get_data_len(subop, op_id);
437 		offset = nand_subop_get_data_start_off(subop, op_id);
438 		force8bit = instr->ctx.data.force_8bit;
439 
440 		code |= COMMAND_READ_DATA;
441 	}
442 
443 	if (force8bit && (chip->options & NAND_BUSWIDTH_16))
444 		vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_16BIT);
445 
446 	cmd2 |= code << CMD_CODE_SHIFT;
447 
448 	vf610_nfc_run(nfc, col, row, cmd1, cmd2, trfr_sz);
449 
450 	if (instr && instr->type == NAND_OP_DATA_IN_INSTR) {
451 		/*
452 		 * Don't fix endianness on page access for historical reasons.
453 		 * See comment in vf610_nfc_rd_from_sram
454 		 */
455 		vf610_nfc_rd_from_sram(instr->ctx.data.buf.in + offset,
456 				       nfc->regs + NFC_MAIN_AREA(0) + offset,
457 				       trfr_sz, !nfc->data_access);
458 	}
459 
460 	if (force8bit && (chip->options & NAND_BUSWIDTH_16))
461 		vf610_nfc_set(nfc, NFC_FLASH_CONFIG, CONFIG_16BIT);
462 
463 	return 0;
464 }
465 
466 static const struct nand_op_parser vf610_nfc_op_parser = NAND_OP_PARSER(
467 	NAND_OP_PARSER_PATTERN(vf610_nfc_cmd,
468 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
469 		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 5),
470 		NAND_OP_PARSER_PAT_DATA_OUT_ELEM(true, PAGE_2K + OOB_MAX),
471 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
472 		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
473 	NAND_OP_PARSER_PATTERN(vf610_nfc_cmd,
474 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
475 		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 5),
476 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
477 		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
478 		NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, PAGE_2K + OOB_MAX)),
479 	);
480 
481 /*
482  * This function supports Vybrid only (MPC5125 would have full RB and four CS)
483  */
484 static void vf610_nfc_select_target(struct nand_chip *chip, unsigned int cs)
485 {
486 	struct vf610_nfc *nfc = chip_to_nfc(chip);
487 	u32 tmp;
488 
489 	/* Vybrid only (MPC5125 would have full RB and four CS) */
490 	if (nfc->variant != NFC_VFC610)
491 		return;
492 
493 	tmp = vf610_nfc_read(nfc, NFC_ROW_ADDR);
494 	tmp &= ~(ROW_ADDR_CHIP_SEL_RB_MASK | ROW_ADDR_CHIP_SEL_MASK);
495 	tmp |= 1 << ROW_ADDR_CHIP_SEL_RB_SHIFT;
496 	tmp |= BIT(cs) << ROW_ADDR_CHIP_SEL_SHIFT;
497 
498 	vf610_nfc_write(nfc, NFC_ROW_ADDR, tmp);
499 }
500 
501 static int vf610_nfc_exec_op(struct nand_chip *chip,
502 			     const struct nand_operation *op,
503 			     bool check_only)
504 {
505 	vf610_nfc_select_target(chip, op->cs);
506 	return nand_op_parser_exec_op(chip, &vf610_nfc_op_parser, op,
507 				      check_only);
508 }
509 
510 static inline int vf610_nfc_correct_data(struct nand_chip *chip, uint8_t *dat,
511 					 uint8_t *oob, int page)
512 {
513 	struct vf610_nfc *nfc = chip_to_nfc(chip);
514 	struct mtd_info *mtd = nand_to_mtd(chip);
515 	u32 ecc_status_off = NFC_MAIN_AREA(0) + ECC_SRAM_ADDR + ECC_STATUS;
516 	u8 ecc_status;
517 	u8 ecc_count;
518 	int flips_threshold = nfc->chip.ecc.strength / 2;
519 
520 	ecc_status = vf610_nfc_read(nfc, ecc_status_off) & 0xff;
521 	ecc_count = ecc_status & ECC_STATUS_ERR_COUNT;
522 
523 	if (!(ecc_status & ECC_STATUS_MASK))
524 		return ecc_count;
525 
526 	nfc->data_access = true;
527 	nand_read_oob_op(&nfc->chip, page, 0, oob, mtd->oobsize);
528 	nfc->data_access = false;
529 
530 	/*
531 	 * On an erased page, bit count (including OOB) should be zero or
532 	 * at least less then half of the ECC strength.
533 	 */
534 	return nand_check_erased_ecc_chunk(dat, nfc->chip.ecc.size, oob,
535 					   mtd->oobsize, NULL, 0,
536 					   flips_threshold);
537 }
538 
539 static void vf610_nfc_fill_row(struct nand_chip *chip, int page, u32 *code,
540 			       u32 *row)
541 {
542 	*row = ROW_ADDR(0, page & 0xff) | ROW_ADDR(1, page >> 8);
543 	*code |= COMMAND_RAR_BYTE1 | COMMAND_RAR_BYTE2;
544 
545 	if (chip->options & NAND_ROW_ADDR_3) {
546 		*row |= ROW_ADDR(2, page >> 16);
547 		*code |= COMMAND_RAR_BYTE3;
548 	}
549 }
550 
551 static int vf610_nfc_read_page(struct nand_chip *chip, uint8_t *buf,
552 			       int oob_required, int page)
553 {
554 	struct vf610_nfc *nfc = chip_to_nfc(chip);
555 	struct mtd_info *mtd = nand_to_mtd(chip);
556 	int trfr_sz = mtd->writesize + mtd->oobsize;
557 	u32 row = 0, cmd1 = 0, cmd2 = 0, code = 0;
558 	int stat;
559 
560 	vf610_nfc_select_target(chip, chip->cur_cs);
561 
562 	cmd2 |= NAND_CMD_READ0 << CMD_BYTE1_SHIFT;
563 	code |= COMMAND_CMD_BYTE1 | COMMAND_CAR_BYTE1 | COMMAND_CAR_BYTE2;
564 
565 	vf610_nfc_fill_row(chip, page, &code, &row);
566 
567 	cmd1 |= NAND_CMD_READSTART << CMD_BYTE2_SHIFT;
568 	code |= COMMAND_CMD_BYTE2 | COMMAND_RB_HANDSHAKE | COMMAND_READ_DATA;
569 
570 	cmd2 |= code << CMD_CODE_SHIFT;
571 
572 	vf610_nfc_ecc_mode(nfc, nfc->ecc_mode);
573 	vf610_nfc_run(nfc, 0, row, cmd1, cmd2, trfr_sz);
574 	vf610_nfc_ecc_mode(nfc, ECC_BYPASS);
575 
576 	/*
577 	 * Don't fix endianness on page access for historical reasons.
578 	 * See comment in vf610_nfc_rd_from_sram
579 	 */
580 	vf610_nfc_rd_from_sram(buf, nfc->regs + NFC_MAIN_AREA(0),
581 			       mtd->writesize, false);
582 	if (oob_required)
583 		vf610_nfc_rd_from_sram(chip->oob_poi,
584 				       nfc->regs + NFC_MAIN_AREA(0) +
585 						   mtd->writesize,
586 				       mtd->oobsize, false);
587 
588 	stat = vf610_nfc_correct_data(chip, buf, chip->oob_poi, page);
589 
590 	if (stat < 0) {
591 		mtd->ecc_stats.failed++;
592 		return 0;
593 	} else {
594 		mtd->ecc_stats.corrected += stat;
595 		return stat;
596 	}
597 }
598 
599 static int vf610_nfc_write_page(struct nand_chip *chip, const uint8_t *buf,
600 				int oob_required, int page)
601 {
602 	struct vf610_nfc *nfc = chip_to_nfc(chip);
603 	struct mtd_info *mtd = nand_to_mtd(chip);
604 	int trfr_sz = mtd->writesize + mtd->oobsize;
605 	u32 row = 0, cmd1 = 0, cmd2 = 0, code = 0;
606 	u8 status;
607 	int ret;
608 
609 	vf610_nfc_select_target(chip, chip->cur_cs);
610 
611 	cmd2 |= NAND_CMD_SEQIN << CMD_BYTE1_SHIFT;
612 	code |= COMMAND_CMD_BYTE1 | COMMAND_CAR_BYTE1 | COMMAND_CAR_BYTE2;
613 
614 	vf610_nfc_fill_row(chip, page, &code, &row);
615 
616 	cmd1 |= NAND_CMD_PAGEPROG << CMD_BYTE2_SHIFT;
617 	code |= COMMAND_CMD_BYTE2 | COMMAND_WRITE_DATA;
618 
619 	/*
620 	 * Don't fix endianness on page access for historical reasons.
621 	 * See comment in vf610_nfc_wr_to_sram
622 	 */
623 	vf610_nfc_wr_to_sram(nfc->regs + NFC_MAIN_AREA(0), buf,
624 			     mtd->writesize, false);
625 
626 	code |= COMMAND_RB_HANDSHAKE;
627 	cmd2 |= code << CMD_CODE_SHIFT;
628 
629 	vf610_nfc_ecc_mode(nfc, nfc->ecc_mode);
630 	vf610_nfc_run(nfc, 0, row, cmd1, cmd2, trfr_sz);
631 	vf610_nfc_ecc_mode(nfc, ECC_BYPASS);
632 
633 	ret = nand_status_op(chip, &status);
634 	if (ret)
635 		return ret;
636 
637 	if (status & NAND_STATUS_FAIL)
638 		return -EIO;
639 
640 	return 0;
641 }
642 
643 static int vf610_nfc_read_page_raw(struct nand_chip *chip, u8 *buf,
644 				   int oob_required, int page)
645 {
646 	struct vf610_nfc *nfc = chip_to_nfc(chip);
647 	int ret;
648 
649 	nfc->data_access = true;
650 	ret = nand_read_page_raw(chip, buf, oob_required, page);
651 	nfc->data_access = false;
652 
653 	return ret;
654 }
655 
656 static int vf610_nfc_write_page_raw(struct nand_chip *chip, const u8 *buf,
657 				    int oob_required, int page)
658 {
659 	struct vf610_nfc *nfc = chip_to_nfc(chip);
660 	struct mtd_info *mtd = nand_to_mtd(chip);
661 	int ret;
662 
663 	nfc->data_access = true;
664 	ret = nand_prog_page_begin_op(chip, page, 0, buf, mtd->writesize);
665 	if (!ret && oob_required)
666 		ret = nand_write_data_op(chip, chip->oob_poi, mtd->oobsize,
667 					 false);
668 	nfc->data_access = false;
669 
670 	if (ret)
671 		return ret;
672 
673 	return nand_prog_page_end_op(chip);
674 }
675 
676 static int vf610_nfc_read_oob(struct nand_chip *chip, int page)
677 {
678 	struct vf610_nfc *nfc = chip_to_nfc(chip);
679 	int ret;
680 
681 	nfc->data_access = true;
682 	ret = nand_read_oob_std(chip, page);
683 	nfc->data_access = false;
684 
685 	return ret;
686 }
687 
688 static int vf610_nfc_write_oob(struct nand_chip *chip, int page)
689 {
690 	struct mtd_info *mtd = nand_to_mtd(chip);
691 	struct vf610_nfc *nfc = chip_to_nfc(chip);
692 	int ret;
693 
694 	nfc->data_access = true;
695 	ret = nand_prog_page_begin_op(chip, page, mtd->writesize,
696 				      chip->oob_poi, mtd->oobsize);
697 	nfc->data_access = false;
698 
699 	if (ret)
700 		return ret;
701 
702 	return nand_prog_page_end_op(chip);
703 }
704 
705 static const struct of_device_id vf610_nfc_dt_ids[] = {
706 	{ .compatible = "fsl,vf610-nfc", .data = (void *)NFC_VFC610 },
707 	{ /* sentinel */ }
708 };
709 MODULE_DEVICE_TABLE(of, vf610_nfc_dt_ids);
710 
711 static void vf610_nfc_preinit_controller(struct vf610_nfc *nfc)
712 {
713 	vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_16BIT);
714 	vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_ADDR_AUTO_INCR_BIT);
715 	vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_BUFNO_AUTO_INCR_BIT);
716 	vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_BOOT_MODE_BIT);
717 	vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_DMA_REQ_BIT);
718 	vf610_nfc_set(nfc, NFC_FLASH_CONFIG, CONFIG_FAST_FLASH_BIT);
719 	vf610_nfc_ecc_mode(nfc, ECC_BYPASS);
720 
721 	/* Disable virtual pages, only one elementary transfer unit */
722 	vf610_nfc_set_field(nfc, NFC_FLASH_CONFIG, CONFIG_PAGE_CNT_MASK,
723 			    CONFIG_PAGE_CNT_SHIFT, 1);
724 }
725 
726 static void vf610_nfc_init_controller(struct vf610_nfc *nfc)
727 {
728 	if (nfc->chip.options & NAND_BUSWIDTH_16)
729 		vf610_nfc_set(nfc, NFC_FLASH_CONFIG, CONFIG_16BIT);
730 	else
731 		vf610_nfc_clear(nfc, NFC_FLASH_CONFIG, CONFIG_16BIT);
732 
733 	if (nfc->chip.ecc.mode == NAND_ECC_HW) {
734 		/* Set ECC status offset in SRAM */
735 		vf610_nfc_set_field(nfc, NFC_FLASH_CONFIG,
736 				    CONFIG_ECC_SRAM_ADDR_MASK,
737 				    CONFIG_ECC_SRAM_ADDR_SHIFT,
738 				    ECC_SRAM_ADDR >> 3);
739 
740 		/* Enable ECC status in SRAM */
741 		vf610_nfc_set(nfc, NFC_FLASH_CONFIG, CONFIG_ECC_SRAM_REQ_BIT);
742 	}
743 }
744 
745 static int vf610_nfc_attach_chip(struct nand_chip *chip)
746 {
747 	struct mtd_info *mtd = nand_to_mtd(chip);
748 	struct vf610_nfc *nfc = chip_to_nfc(chip);
749 
750 	vf610_nfc_init_controller(nfc);
751 
752 	/* Bad block options. */
753 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
754 		chip->bbt_options |= NAND_BBT_NO_OOB;
755 
756 	/* Single buffer only, max 256 OOB minus ECC status */
757 	if (mtd->writesize + mtd->oobsize > PAGE_2K + OOB_MAX - 8) {
758 		dev_err(nfc->dev, "Unsupported flash page size\n");
759 		return -ENXIO;
760 	}
761 
762 	if (chip->ecc.mode != NAND_ECC_HW)
763 		return 0;
764 
765 	if (mtd->writesize != PAGE_2K && mtd->oobsize < 64) {
766 		dev_err(nfc->dev, "Unsupported flash with hwecc\n");
767 		return -ENXIO;
768 	}
769 
770 	if (chip->ecc.size != mtd->writesize) {
771 		dev_err(nfc->dev, "Step size needs to be page size\n");
772 		return -ENXIO;
773 	}
774 
775 	/* Only 64 byte ECC layouts known */
776 	if (mtd->oobsize > 64)
777 		mtd->oobsize = 64;
778 
779 	/* Use default large page ECC layout defined in NAND core */
780 	mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
781 	if (chip->ecc.strength == 32) {
782 		nfc->ecc_mode = ECC_60_BYTE;
783 		chip->ecc.bytes = 60;
784 	} else if (chip->ecc.strength == 24) {
785 		nfc->ecc_mode = ECC_45_BYTE;
786 		chip->ecc.bytes = 45;
787 	} else {
788 		dev_err(nfc->dev, "Unsupported ECC strength\n");
789 		return -ENXIO;
790 	}
791 
792 	chip->ecc.read_page = vf610_nfc_read_page;
793 	chip->ecc.write_page = vf610_nfc_write_page;
794 	chip->ecc.read_page_raw = vf610_nfc_read_page_raw;
795 	chip->ecc.write_page_raw = vf610_nfc_write_page_raw;
796 	chip->ecc.read_oob = vf610_nfc_read_oob;
797 	chip->ecc.write_oob = vf610_nfc_write_oob;
798 
799 	chip->ecc.size = PAGE_2K;
800 
801 	return 0;
802 }
803 
804 static const struct nand_controller_ops vf610_nfc_controller_ops = {
805 	.attach_chip = vf610_nfc_attach_chip,
806 	.exec_op = vf610_nfc_exec_op,
807 
808 };
809 
810 static int vf610_nfc_probe(struct platform_device *pdev)
811 {
812 	struct vf610_nfc *nfc;
813 	struct resource *res;
814 	struct mtd_info *mtd;
815 	struct nand_chip *chip;
816 	struct device_node *child;
817 	const struct of_device_id *of_id;
818 	int err;
819 	int irq;
820 
821 	nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL);
822 	if (!nfc)
823 		return -ENOMEM;
824 
825 	nfc->dev = &pdev->dev;
826 	chip = &nfc->chip;
827 	mtd = nand_to_mtd(chip);
828 
829 	mtd->owner = THIS_MODULE;
830 	mtd->dev.parent = nfc->dev;
831 	mtd->name = DRV_NAME;
832 
833 	irq = platform_get_irq(pdev, 0);
834 	if (irq <= 0)
835 		return -EINVAL;
836 
837 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
838 	nfc->regs = devm_ioremap_resource(nfc->dev, res);
839 	if (IS_ERR(nfc->regs))
840 		return PTR_ERR(nfc->regs);
841 
842 	nfc->clk = devm_clk_get(&pdev->dev, NULL);
843 	if (IS_ERR(nfc->clk))
844 		return PTR_ERR(nfc->clk);
845 
846 	err = clk_prepare_enable(nfc->clk);
847 	if (err) {
848 		dev_err(nfc->dev, "Unable to enable clock!\n");
849 		return err;
850 	}
851 
852 	of_id = of_match_device(vf610_nfc_dt_ids, &pdev->dev);
853 	if (!of_id)
854 		return -ENODEV;
855 
856 	nfc->variant = (enum vf610_nfc_variant)of_id->data;
857 
858 	for_each_available_child_of_node(nfc->dev->of_node, child) {
859 		if (of_device_is_compatible(child, "fsl,vf610-nfc-nandcs")) {
860 
861 			if (nand_get_flash_node(chip)) {
862 				dev_err(nfc->dev,
863 					"Only one NAND chip supported!\n");
864 				err = -EINVAL;
865 				goto err_disable_clk;
866 			}
867 
868 			nand_set_flash_node(chip, child);
869 		}
870 	}
871 
872 	if (!nand_get_flash_node(chip)) {
873 		dev_err(nfc->dev, "NAND chip sub-node missing!\n");
874 		err = -ENODEV;
875 		goto err_disable_clk;
876 	}
877 
878 	chip->options |= NAND_NO_SUBPAGE_WRITE;
879 
880 	init_completion(&nfc->cmd_done);
881 
882 	err = devm_request_irq(nfc->dev, irq, vf610_nfc_irq, 0, DRV_NAME, nfc);
883 	if (err) {
884 		dev_err(nfc->dev, "Error requesting IRQ!\n");
885 		goto err_disable_clk;
886 	}
887 
888 	vf610_nfc_preinit_controller(nfc);
889 
890 	nand_controller_init(&nfc->base);
891 	nfc->base.ops = &vf610_nfc_controller_ops;
892 	chip->controller = &nfc->base;
893 
894 	/* Scan the NAND chip */
895 	err = nand_scan(chip, 1);
896 	if (err)
897 		goto err_disable_clk;
898 
899 	platform_set_drvdata(pdev, nfc);
900 
901 	/* Register device in MTD */
902 	err = mtd_device_register(mtd, NULL, 0);
903 	if (err)
904 		goto err_cleanup_nand;
905 	return 0;
906 
907 err_cleanup_nand:
908 	nand_cleanup(chip);
909 err_disable_clk:
910 	clk_disable_unprepare(nfc->clk);
911 	return err;
912 }
913 
914 static int vf610_nfc_remove(struct platform_device *pdev)
915 {
916 	struct vf610_nfc *nfc = platform_get_drvdata(pdev);
917 
918 	nand_release(&nfc->chip);
919 	clk_disable_unprepare(nfc->clk);
920 	return 0;
921 }
922 
923 #ifdef CONFIG_PM_SLEEP
924 static int vf610_nfc_suspend(struct device *dev)
925 {
926 	struct vf610_nfc *nfc = dev_get_drvdata(dev);
927 
928 	clk_disable_unprepare(nfc->clk);
929 	return 0;
930 }
931 
932 static int vf610_nfc_resume(struct device *dev)
933 {
934 	struct vf610_nfc *nfc = dev_get_drvdata(dev);
935 	int err;
936 
937 	err = clk_prepare_enable(nfc->clk);
938 	if (err)
939 		return err;
940 
941 	vf610_nfc_preinit_controller(nfc);
942 	vf610_nfc_init_controller(nfc);
943 	return 0;
944 }
945 #endif
946 
947 static SIMPLE_DEV_PM_OPS(vf610_nfc_pm_ops, vf610_nfc_suspend, vf610_nfc_resume);
948 
949 static struct platform_driver vf610_nfc_driver = {
950 	.driver		= {
951 		.name	= DRV_NAME,
952 		.of_match_table = vf610_nfc_dt_ids,
953 		.pm	= &vf610_nfc_pm_ops,
954 	},
955 	.probe		= vf610_nfc_probe,
956 	.remove		= vf610_nfc_remove,
957 };
958 
959 module_platform_driver(vf610_nfc_driver);
960 
961 MODULE_AUTHOR("Stefan Agner <stefan.agner@toradex.com>");
962 MODULE_DESCRIPTION("Freescale VF610/MPC5125 NFC MTD NAND driver");
963 MODULE_LICENSE("GPL");
964