xref: /openbmc/linux/drivers/mtd/nand/raw/denali.c (revision a99237af)
1 /*
2  * NAND Flash Controller Device Driver
3  * Copyright © 2009-2010, Intel Corporation and its suppliers.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #include <linux/bitfield.h>
16 #include <linux/completion.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/mtd/rawnand.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 
26 #include "denali.h"
27 
28 MODULE_LICENSE("GPL");
29 
30 #define DENALI_NAND_NAME    "denali-nand"
31 
32 /* for Indexed Addressing */
33 #define DENALI_INDEXED_CTRL	0x00
34 #define DENALI_INDEXED_DATA	0x10
35 
36 #define DENALI_MAP00		(0 << 26)	/* direct access to buffer */
37 #define DENALI_MAP01		(1 << 26)	/* read/write pages in PIO */
38 #define DENALI_MAP10		(2 << 26)	/* high-level control plane */
39 #define DENALI_MAP11		(3 << 26)	/* direct controller access */
40 
41 /* MAP11 access cycle type */
42 #define DENALI_MAP11_CMD	((DENALI_MAP11) | 0)	/* command cycle */
43 #define DENALI_MAP11_ADDR	((DENALI_MAP11) | 1)	/* address cycle */
44 #define DENALI_MAP11_DATA	((DENALI_MAP11) | 2)	/* data cycle */
45 
46 /* MAP10 commands */
47 #define DENALI_ERASE		0x01
48 
49 #define DENALI_BANK(denali)	((denali)->active_bank << 24)
50 
51 #define DENALI_INVALID_BANK	-1
52 #define DENALI_NR_BANKS		4
53 
54 static inline struct denali_nand_info *mtd_to_denali(struct mtd_info *mtd)
55 {
56 	return container_of(mtd_to_nand(mtd), struct denali_nand_info, nand);
57 }
58 
59 /*
60  * Direct Addressing - the slave address forms the control information (command
61  * type, bank, block, and page address).  The slave data is the actual data to
62  * be transferred.  This mode requires 28 bits of address region allocated.
63  */
64 static u32 denali_direct_read(struct denali_nand_info *denali, u32 addr)
65 {
66 	return ioread32(denali->host + addr);
67 }
68 
69 static void denali_direct_write(struct denali_nand_info *denali, u32 addr,
70 				u32 data)
71 {
72 	iowrite32(data, denali->host + addr);
73 }
74 
75 /*
76  * Indexed Addressing - address translation module intervenes in passing the
77  * control information.  This mode reduces the required address range.  The
78  * control information and transferred data are latched by the registers in
79  * the translation module.
80  */
81 static u32 denali_indexed_read(struct denali_nand_info *denali, u32 addr)
82 {
83 	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
84 	return ioread32(denali->host + DENALI_INDEXED_DATA);
85 }
86 
87 static void denali_indexed_write(struct denali_nand_info *denali, u32 addr,
88 				 u32 data)
89 {
90 	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
91 	iowrite32(data, denali->host + DENALI_INDEXED_DATA);
92 }
93 
94 /*
95  * Use the configuration feature register to determine the maximum number of
96  * banks that the hardware supports.
97  */
98 static void denali_detect_max_banks(struct denali_nand_info *denali)
99 {
100 	uint32_t features = ioread32(denali->reg + FEATURES);
101 
102 	denali->max_banks = 1 << FIELD_GET(FEATURES__N_BANKS, features);
103 
104 	/* the encoding changed from rev 5.0 to 5.1 */
105 	if (denali->revision < 0x0501)
106 		denali->max_banks <<= 1;
107 }
108 
109 static void denali_enable_irq(struct denali_nand_info *denali)
110 {
111 	int i;
112 
113 	for (i = 0; i < DENALI_NR_BANKS; i++)
114 		iowrite32(U32_MAX, denali->reg + INTR_EN(i));
115 	iowrite32(GLOBAL_INT_EN_FLAG, denali->reg + GLOBAL_INT_ENABLE);
116 }
117 
118 static void denali_disable_irq(struct denali_nand_info *denali)
119 {
120 	int i;
121 
122 	for (i = 0; i < DENALI_NR_BANKS; i++)
123 		iowrite32(0, denali->reg + INTR_EN(i));
124 	iowrite32(0, denali->reg + GLOBAL_INT_ENABLE);
125 }
126 
127 static void denali_clear_irq(struct denali_nand_info *denali,
128 			     int bank, uint32_t irq_status)
129 {
130 	/* write one to clear bits */
131 	iowrite32(irq_status, denali->reg + INTR_STATUS(bank));
132 }
133 
134 static void denali_clear_irq_all(struct denali_nand_info *denali)
135 {
136 	int i;
137 
138 	for (i = 0; i < DENALI_NR_BANKS; i++)
139 		denali_clear_irq(denali, i, U32_MAX);
140 }
141 
142 static irqreturn_t denali_isr(int irq, void *dev_id)
143 {
144 	struct denali_nand_info *denali = dev_id;
145 	irqreturn_t ret = IRQ_NONE;
146 	uint32_t irq_status;
147 	int i;
148 
149 	spin_lock(&denali->irq_lock);
150 
151 	for (i = 0; i < DENALI_NR_BANKS; i++) {
152 		irq_status = ioread32(denali->reg + INTR_STATUS(i));
153 		if (irq_status)
154 			ret = IRQ_HANDLED;
155 
156 		denali_clear_irq(denali, i, irq_status);
157 
158 		if (i != denali->active_bank)
159 			continue;
160 
161 		denali->irq_status |= irq_status;
162 
163 		if (denali->irq_status & denali->irq_mask)
164 			complete(&denali->complete);
165 	}
166 
167 	spin_unlock(&denali->irq_lock);
168 
169 	return ret;
170 }
171 
172 static void denali_reset_irq(struct denali_nand_info *denali)
173 {
174 	unsigned long flags;
175 
176 	spin_lock_irqsave(&denali->irq_lock, flags);
177 	denali->irq_status = 0;
178 	denali->irq_mask = 0;
179 	spin_unlock_irqrestore(&denali->irq_lock, flags);
180 }
181 
182 static uint32_t denali_wait_for_irq(struct denali_nand_info *denali,
183 				    uint32_t irq_mask)
184 {
185 	unsigned long time_left, flags;
186 	uint32_t irq_status;
187 
188 	spin_lock_irqsave(&denali->irq_lock, flags);
189 
190 	irq_status = denali->irq_status;
191 
192 	if (irq_mask & irq_status) {
193 		/* return immediately if the IRQ has already happened. */
194 		spin_unlock_irqrestore(&denali->irq_lock, flags);
195 		return irq_status;
196 	}
197 
198 	denali->irq_mask = irq_mask;
199 	reinit_completion(&denali->complete);
200 	spin_unlock_irqrestore(&denali->irq_lock, flags);
201 
202 	time_left = wait_for_completion_timeout(&denali->complete,
203 						msecs_to_jiffies(1000));
204 	if (!time_left) {
205 		dev_err(denali->dev, "timeout while waiting for irq 0x%x\n",
206 			irq_mask);
207 		return 0;
208 	}
209 
210 	return denali->irq_status;
211 }
212 
213 static uint32_t denali_check_irq(struct denali_nand_info *denali)
214 {
215 	unsigned long flags;
216 	uint32_t irq_status;
217 
218 	spin_lock_irqsave(&denali->irq_lock, flags);
219 	irq_status = denali->irq_status;
220 	spin_unlock_irqrestore(&denali->irq_lock, flags);
221 
222 	return irq_status;
223 }
224 
225 static void denali_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
226 {
227 	struct denali_nand_info *denali = mtd_to_denali(mtd);
228 	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
229 	int i;
230 
231 	for (i = 0; i < len; i++)
232 		buf[i] = denali->host_read(denali, addr);
233 }
234 
235 static void denali_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
236 {
237 	struct denali_nand_info *denali = mtd_to_denali(mtd);
238 	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
239 	int i;
240 
241 	for (i = 0; i < len; i++)
242 		denali->host_write(denali, addr, buf[i]);
243 }
244 
245 static void denali_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
246 {
247 	struct denali_nand_info *denali = mtd_to_denali(mtd);
248 	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
249 	uint16_t *buf16 = (uint16_t *)buf;
250 	int i;
251 
252 	for (i = 0; i < len / 2; i++)
253 		buf16[i] = denali->host_read(denali, addr);
254 }
255 
256 static void denali_write_buf16(struct mtd_info *mtd, const uint8_t *buf,
257 			       int len)
258 {
259 	struct denali_nand_info *denali = mtd_to_denali(mtd);
260 	u32 addr = DENALI_MAP11_DATA | DENALI_BANK(denali);
261 	const uint16_t *buf16 = (const uint16_t *)buf;
262 	int i;
263 
264 	for (i = 0; i < len / 2; i++)
265 		denali->host_write(denali, addr, buf16[i]);
266 }
267 
268 static uint8_t denali_read_byte(struct mtd_info *mtd)
269 {
270 	uint8_t byte;
271 
272 	denali_read_buf(mtd, &byte, 1);
273 
274 	return byte;
275 }
276 
277 static void denali_write_byte(struct mtd_info *mtd, uint8_t byte)
278 {
279 	denali_write_buf(mtd, &byte, 1);
280 }
281 
282 static uint16_t denali_read_word(struct mtd_info *mtd)
283 {
284 	uint16_t word;
285 
286 	denali_read_buf16(mtd, (uint8_t *)&word, 2);
287 
288 	return word;
289 }
290 
291 static void denali_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
292 {
293 	struct denali_nand_info *denali = mtd_to_denali(mtd);
294 	uint32_t type;
295 
296 	if (ctrl & NAND_CLE)
297 		type = DENALI_MAP11_CMD;
298 	else if (ctrl & NAND_ALE)
299 		type = DENALI_MAP11_ADDR;
300 	else
301 		return;
302 
303 	/*
304 	 * Some commands are followed by chip->dev_ready or chip->waitfunc.
305 	 * irq_status must be cleared here to catch the R/B# interrupt later.
306 	 */
307 	if (ctrl & NAND_CTRL_CHANGE)
308 		denali_reset_irq(denali);
309 
310 	denali->host_write(denali, DENALI_BANK(denali) | type, dat);
311 }
312 
313 static int denali_dev_ready(struct mtd_info *mtd)
314 {
315 	struct denali_nand_info *denali = mtd_to_denali(mtd);
316 
317 	return !!(denali_check_irq(denali) & INTR__INT_ACT);
318 }
319 
320 static int denali_check_erased_page(struct mtd_info *mtd,
321 				    struct nand_chip *chip, uint8_t *buf,
322 				    unsigned long uncor_ecc_flags,
323 				    unsigned int max_bitflips)
324 {
325 	struct denali_nand_info *denali = mtd_to_denali(mtd);
326 	uint8_t *ecc_code = chip->oob_poi + denali->oob_skip_bytes;
327 	int ecc_steps = chip->ecc.steps;
328 	int ecc_size = chip->ecc.size;
329 	int ecc_bytes = chip->ecc.bytes;
330 	int i, stat;
331 
332 	for (i = 0; i < ecc_steps; i++) {
333 		if (!(uncor_ecc_flags & BIT(i)))
334 			continue;
335 
336 		stat = nand_check_erased_ecc_chunk(buf, ecc_size,
337 						  ecc_code, ecc_bytes,
338 						  NULL, 0,
339 						  chip->ecc.strength);
340 		if (stat < 0) {
341 			mtd->ecc_stats.failed++;
342 		} else {
343 			mtd->ecc_stats.corrected += stat;
344 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
345 		}
346 
347 		buf += ecc_size;
348 		ecc_code += ecc_bytes;
349 	}
350 
351 	return max_bitflips;
352 }
353 
354 static int denali_hw_ecc_fixup(struct mtd_info *mtd,
355 			       struct denali_nand_info *denali,
356 			       unsigned long *uncor_ecc_flags)
357 {
358 	struct nand_chip *chip = mtd_to_nand(mtd);
359 	int bank = denali->active_bank;
360 	uint32_t ecc_cor;
361 	unsigned int max_bitflips;
362 
363 	ecc_cor = ioread32(denali->reg + ECC_COR_INFO(bank));
364 	ecc_cor >>= ECC_COR_INFO__SHIFT(bank);
365 
366 	if (ecc_cor & ECC_COR_INFO__UNCOR_ERR) {
367 		/*
368 		 * This flag is set when uncorrectable error occurs at least in
369 		 * one ECC sector.  We can not know "how many sectors", or
370 		 * "which sector(s)".  We need erase-page check for all sectors.
371 		 */
372 		*uncor_ecc_flags = GENMASK(chip->ecc.steps - 1, 0);
373 		return 0;
374 	}
375 
376 	max_bitflips = FIELD_GET(ECC_COR_INFO__MAX_ERRORS, ecc_cor);
377 
378 	/*
379 	 * The register holds the maximum of per-sector corrected bitflips.
380 	 * This is suitable for the return value of the ->read_page() callback.
381 	 * Unfortunately, we can not know the total number of corrected bits in
382 	 * the page.  Increase the stats by max_bitflips. (compromised solution)
383 	 */
384 	mtd->ecc_stats.corrected += max_bitflips;
385 
386 	return max_bitflips;
387 }
388 
389 static int denali_sw_ecc_fixup(struct mtd_info *mtd,
390 			       struct denali_nand_info *denali,
391 			       unsigned long *uncor_ecc_flags, uint8_t *buf)
392 {
393 	unsigned int ecc_size = denali->nand.ecc.size;
394 	unsigned int bitflips = 0;
395 	unsigned int max_bitflips = 0;
396 	uint32_t err_addr, err_cor_info;
397 	unsigned int err_byte, err_sector, err_device;
398 	uint8_t err_cor_value;
399 	unsigned int prev_sector = 0;
400 	uint32_t irq_status;
401 
402 	denali_reset_irq(denali);
403 
404 	do {
405 		err_addr = ioread32(denali->reg + ECC_ERROR_ADDRESS);
406 		err_sector = FIELD_GET(ECC_ERROR_ADDRESS__SECTOR, err_addr);
407 		err_byte = FIELD_GET(ECC_ERROR_ADDRESS__OFFSET, err_addr);
408 
409 		err_cor_info = ioread32(denali->reg + ERR_CORRECTION_INFO);
410 		err_cor_value = FIELD_GET(ERR_CORRECTION_INFO__BYTE,
411 					  err_cor_info);
412 		err_device = FIELD_GET(ERR_CORRECTION_INFO__DEVICE,
413 				       err_cor_info);
414 
415 		/* reset the bitflip counter when crossing ECC sector */
416 		if (err_sector != prev_sector)
417 			bitflips = 0;
418 
419 		if (err_cor_info & ERR_CORRECTION_INFO__UNCOR) {
420 			/*
421 			 * Check later if this is a real ECC error, or
422 			 * an erased sector.
423 			 */
424 			*uncor_ecc_flags |= BIT(err_sector);
425 		} else if (err_byte < ecc_size) {
426 			/*
427 			 * If err_byte is larger than ecc_size, means error
428 			 * happened in OOB, so we ignore it. It's no need for
429 			 * us to correct it err_device is represented the NAND
430 			 * error bits are happened in if there are more than
431 			 * one NAND connected.
432 			 */
433 			int offset;
434 			unsigned int flips_in_byte;
435 
436 			offset = (err_sector * ecc_size + err_byte) *
437 					denali->devs_per_cs + err_device;
438 
439 			/* correct the ECC error */
440 			flips_in_byte = hweight8(buf[offset] ^ err_cor_value);
441 			buf[offset] ^= err_cor_value;
442 			mtd->ecc_stats.corrected += flips_in_byte;
443 			bitflips += flips_in_byte;
444 
445 			max_bitflips = max(max_bitflips, bitflips);
446 		}
447 
448 		prev_sector = err_sector;
449 	} while (!(err_cor_info & ERR_CORRECTION_INFO__LAST_ERR));
450 
451 	/*
452 	 * Once handle all ECC errors, controller will trigger an
453 	 * ECC_TRANSACTION_DONE interrupt.
454 	 */
455 	irq_status = denali_wait_for_irq(denali, INTR__ECC_TRANSACTION_DONE);
456 	if (!(irq_status & INTR__ECC_TRANSACTION_DONE))
457 		return -EIO;
458 
459 	return max_bitflips;
460 }
461 
462 static void denali_setup_dma64(struct denali_nand_info *denali,
463 			       dma_addr_t dma_addr, int page, int write)
464 {
465 	uint32_t mode;
466 	const int page_count = 1;
467 
468 	mode = DENALI_MAP10 | DENALI_BANK(denali) | page;
469 
470 	/* DMA is a three step process */
471 
472 	/*
473 	 * 1. setup transfer type, interrupt when complete,
474 	 *    burst len = 64 bytes, the number of pages
475 	 */
476 	denali->host_write(denali, mode,
477 			   0x01002000 | (64 << 16) | (write << 8) | page_count);
478 
479 	/* 2. set memory low address */
480 	denali->host_write(denali, mode, lower_32_bits(dma_addr));
481 
482 	/* 3. set memory high address */
483 	denali->host_write(denali, mode, upper_32_bits(dma_addr));
484 }
485 
486 static void denali_setup_dma32(struct denali_nand_info *denali,
487 			       dma_addr_t dma_addr, int page, int write)
488 {
489 	uint32_t mode;
490 	const int page_count = 1;
491 
492 	mode = DENALI_MAP10 | DENALI_BANK(denali);
493 
494 	/* DMA is a four step process */
495 
496 	/* 1. setup transfer type and # of pages */
497 	denali->host_write(denali, mode | page,
498 			   0x2000 | (write << 8) | page_count);
499 
500 	/* 2. set memory high address bits 23:8 */
501 	denali->host_write(denali, mode | ((dma_addr >> 16) << 8), 0x2200);
502 
503 	/* 3. set memory low address bits 23:8 */
504 	denali->host_write(denali, mode | ((dma_addr & 0xffff) << 8), 0x2300);
505 
506 	/* 4. interrupt when complete, burst len = 64 bytes */
507 	denali->host_write(denali, mode | 0x14000, 0x2400);
508 }
509 
510 static int denali_pio_read(struct denali_nand_info *denali, void *buf,
511 			   size_t size, int page, int raw)
512 {
513 	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
514 	uint32_t *buf32 = (uint32_t *)buf;
515 	uint32_t irq_status, ecc_err_mask;
516 	int i;
517 
518 	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
519 		ecc_err_mask = INTR__ECC_UNCOR_ERR;
520 	else
521 		ecc_err_mask = INTR__ECC_ERR;
522 
523 	denali_reset_irq(denali);
524 
525 	for (i = 0; i < size / 4; i++)
526 		*buf32++ = denali->host_read(denali, addr);
527 
528 	irq_status = denali_wait_for_irq(denali, INTR__PAGE_XFER_INC);
529 	if (!(irq_status & INTR__PAGE_XFER_INC))
530 		return -EIO;
531 
532 	if (irq_status & INTR__ERASED_PAGE)
533 		memset(buf, 0xff, size);
534 
535 	return irq_status & ecc_err_mask ? -EBADMSG : 0;
536 }
537 
538 static int denali_pio_write(struct denali_nand_info *denali,
539 			    const void *buf, size_t size, int page, int raw)
540 {
541 	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
542 	const uint32_t *buf32 = (uint32_t *)buf;
543 	uint32_t irq_status;
544 	int i;
545 
546 	denali_reset_irq(denali);
547 
548 	for (i = 0; i < size / 4; i++)
549 		denali->host_write(denali, addr, *buf32++);
550 
551 	irq_status = denali_wait_for_irq(denali,
552 				INTR__PROGRAM_COMP | INTR__PROGRAM_FAIL);
553 	if (!(irq_status & INTR__PROGRAM_COMP))
554 		return -EIO;
555 
556 	return 0;
557 }
558 
559 static int denali_pio_xfer(struct denali_nand_info *denali, void *buf,
560 			   size_t size, int page, int raw, int write)
561 {
562 	if (write)
563 		return denali_pio_write(denali, buf, size, page, raw);
564 	else
565 		return denali_pio_read(denali, buf, size, page, raw);
566 }
567 
568 static int denali_dma_xfer(struct denali_nand_info *denali, void *buf,
569 			   size_t size, int page, int raw, int write)
570 {
571 	dma_addr_t dma_addr;
572 	uint32_t irq_mask, irq_status, ecc_err_mask;
573 	enum dma_data_direction dir = write ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
574 	int ret = 0;
575 
576 	dma_addr = dma_map_single(denali->dev, buf, size, dir);
577 	if (dma_mapping_error(denali->dev, dma_addr)) {
578 		dev_dbg(denali->dev, "Failed to DMA-map buffer. Trying PIO.\n");
579 		return denali_pio_xfer(denali, buf, size, page, raw, write);
580 	}
581 
582 	if (write) {
583 		/*
584 		 * INTR__PROGRAM_COMP is never asserted for the DMA transfer.
585 		 * We can use INTR__DMA_CMD_COMP instead.  This flag is asserted
586 		 * when the page program is completed.
587 		 */
588 		irq_mask = INTR__DMA_CMD_COMP | INTR__PROGRAM_FAIL;
589 		ecc_err_mask = 0;
590 	} else if (denali->caps & DENALI_CAP_HW_ECC_FIXUP) {
591 		irq_mask = INTR__DMA_CMD_COMP;
592 		ecc_err_mask = INTR__ECC_UNCOR_ERR;
593 	} else {
594 		irq_mask = INTR__DMA_CMD_COMP;
595 		ecc_err_mask = INTR__ECC_ERR;
596 	}
597 
598 	iowrite32(DMA_ENABLE__FLAG, denali->reg + DMA_ENABLE);
599 
600 	denali_reset_irq(denali);
601 	denali->setup_dma(denali, dma_addr, page, write);
602 
603 	irq_status = denali_wait_for_irq(denali, irq_mask);
604 	if (!(irq_status & INTR__DMA_CMD_COMP))
605 		ret = -EIO;
606 	else if (irq_status & ecc_err_mask)
607 		ret = -EBADMSG;
608 
609 	iowrite32(0, denali->reg + DMA_ENABLE);
610 
611 	dma_unmap_single(denali->dev, dma_addr, size, dir);
612 
613 	if (irq_status & INTR__ERASED_PAGE)
614 		memset(buf, 0xff, size);
615 
616 	return ret;
617 }
618 
619 static int denali_data_xfer(struct denali_nand_info *denali, void *buf,
620 			    size_t size, int page, int raw, int write)
621 {
622 	iowrite32(raw ? 0 : ECC_ENABLE__FLAG, denali->reg + ECC_ENABLE);
623 	iowrite32(raw ? TRANSFER_SPARE_REG__FLAG : 0,
624 		  denali->reg + TRANSFER_SPARE_REG);
625 
626 	if (denali->dma_avail)
627 		return denali_dma_xfer(denali, buf, size, page, raw, write);
628 	else
629 		return denali_pio_xfer(denali, buf, size, page, raw, write);
630 }
631 
632 static void denali_oob_xfer(struct mtd_info *mtd, struct nand_chip *chip,
633 			    int page, int write)
634 {
635 	struct denali_nand_info *denali = mtd_to_denali(mtd);
636 	int writesize = mtd->writesize;
637 	int oobsize = mtd->oobsize;
638 	uint8_t *bufpoi = chip->oob_poi;
639 	int ecc_steps = chip->ecc.steps;
640 	int ecc_size = chip->ecc.size;
641 	int ecc_bytes = chip->ecc.bytes;
642 	int oob_skip = denali->oob_skip_bytes;
643 	size_t size = writesize + oobsize;
644 	int i, pos, len;
645 
646 	/* BBM at the beginning of the OOB area */
647 	if (write)
648 		nand_prog_page_begin_op(chip, page, writesize, bufpoi,
649 					oob_skip);
650 	else
651 		nand_read_page_op(chip, page, writesize, bufpoi, oob_skip);
652 	bufpoi += oob_skip;
653 
654 	/* OOB ECC */
655 	for (i = 0; i < ecc_steps; i++) {
656 		pos = ecc_size + i * (ecc_size + ecc_bytes);
657 		len = ecc_bytes;
658 
659 		if (pos >= writesize)
660 			pos += oob_skip;
661 		else if (pos + len > writesize)
662 			len = writesize - pos;
663 
664 		if (write)
665 			nand_change_write_column_op(chip, pos, bufpoi, len,
666 						    false);
667 		else
668 			nand_change_read_column_op(chip, pos, bufpoi, len,
669 						   false);
670 		bufpoi += len;
671 		if (len < ecc_bytes) {
672 			len = ecc_bytes - len;
673 			if (write)
674 				nand_change_write_column_op(chip, writesize +
675 							    oob_skip, bufpoi,
676 							    len, false);
677 			else
678 				nand_change_read_column_op(chip, writesize +
679 							   oob_skip, bufpoi,
680 							   len, false);
681 			bufpoi += len;
682 		}
683 	}
684 
685 	/* OOB free */
686 	len = oobsize - (bufpoi - chip->oob_poi);
687 	if (write)
688 		nand_change_write_column_op(chip, size - len, bufpoi, len,
689 					    false);
690 	else
691 		nand_change_read_column_op(chip, size - len, bufpoi, len,
692 					   false);
693 }
694 
695 static int denali_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
696 				uint8_t *buf, int oob_required, int page)
697 {
698 	struct denali_nand_info *denali = mtd_to_denali(mtd);
699 	int writesize = mtd->writesize;
700 	int oobsize = mtd->oobsize;
701 	int ecc_steps = chip->ecc.steps;
702 	int ecc_size = chip->ecc.size;
703 	int ecc_bytes = chip->ecc.bytes;
704 	void *tmp_buf = denali->buf;
705 	int oob_skip = denali->oob_skip_bytes;
706 	size_t size = writesize + oobsize;
707 	int ret, i, pos, len;
708 
709 	ret = denali_data_xfer(denali, tmp_buf, size, page, 1, 0);
710 	if (ret)
711 		return ret;
712 
713 	/* Arrange the buffer for syndrome payload/ecc layout */
714 	if (buf) {
715 		for (i = 0; i < ecc_steps; i++) {
716 			pos = i * (ecc_size + ecc_bytes);
717 			len = ecc_size;
718 
719 			if (pos >= writesize)
720 				pos += oob_skip;
721 			else if (pos + len > writesize)
722 				len = writesize - pos;
723 
724 			memcpy(buf, tmp_buf + pos, len);
725 			buf += len;
726 			if (len < ecc_size) {
727 				len = ecc_size - len;
728 				memcpy(buf, tmp_buf + writesize + oob_skip,
729 				       len);
730 				buf += len;
731 			}
732 		}
733 	}
734 
735 	if (oob_required) {
736 		uint8_t *oob = chip->oob_poi;
737 
738 		/* BBM at the beginning of the OOB area */
739 		memcpy(oob, tmp_buf + writesize, oob_skip);
740 		oob += oob_skip;
741 
742 		/* OOB ECC */
743 		for (i = 0; i < ecc_steps; i++) {
744 			pos = ecc_size + i * (ecc_size + ecc_bytes);
745 			len = ecc_bytes;
746 
747 			if (pos >= writesize)
748 				pos += oob_skip;
749 			else if (pos + len > writesize)
750 				len = writesize - pos;
751 
752 			memcpy(oob, tmp_buf + pos, len);
753 			oob += len;
754 			if (len < ecc_bytes) {
755 				len = ecc_bytes - len;
756 				memcpy(oob, tmp_buf + writesize + oob_skip,
757 				       len);
758 				oob += len;
759 			}
760 		}
761 
762 		/* OOB free */
763 		len = oobsize - (oob - chip->oob_poi);
764 		memcpy(oob, tmp_buf + size - len, len);
765 	}
766 
767 	return 0;
768 }
769 
770 static int denali_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
771 			   int page)
772 {
773 	denali_oob_xfer(mtd, chip, page, 0);
774 
775 	return 0;
776 }
777 
778 static int denali_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
779 			    int page)
780 {
781 	struct denali_nand_info *denali = mtd_to_denali(mtd);
782 
783 	denali_reset_irq(denali);
784 
785 	denali_oob_xfer(mtd, chip, page, 1);
786 
787 	return nand_prog_page_end_op(chip);
788 }
789 
790 static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip,
791 			    uint8_t *buf, int oob_required, int page)
792 {
793 	struct denali_nand_info *denali = mtd_to_denali(mtd);
794 	unsigned long uncor_ecc_flags = 0;
795 	int stat = 0;
796 	int ret;
797 
798 	ret = denali_data_xfer(denali, buf, mtd->writesize, page, 0, 0);
799 	if (ret && ret != -EBADMSG)
800 		return ret;
801 
802 	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
803 		stat = denali_hw_ecc_fixup(mtd, denali, &uncor_ecc_flags);
804 	else if (ret == -EBADMSG)
805 		stat = denali_sw_ecc_fixup(mtd, denali, &uncor_ecc_flags, buf);
806 
807 	if (stat < 0)
808 		return stat;
809 
810 	if (uncor_ecc_flags) {
811 		ret = denali_read_oob(mtd, chip, page);
812 		if (ret)
813 			return ret;
814 
815 		stat = denali_check_erased_page(mtd, chip, buf,
816 						uncor_ecc_flags, stat);
817 	}
818 
819 	return stat;
820 }
821 
822 static int denali_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
823 				 const uint8_t *buf, int oob_required, int page)
824 {
825 	struct denali_nand_info *denali = mtd_to_denali(mtd);
826 	int writesize = mtd->writesize;
827 	int oobsize = mtd->oobsize;
828 	int ecc_steps = chip->ecc.steps;
829 	int ecc_size = chip->ecc.size;
830 	int ecc_bytes = chip->ecc.bytes;
831 	void *tmp_buf = denali->buf;
832 	int oob_skip = denali->oob_skip_bytes;
833 	size_t size = writesize + oobsize;
834 	int i, pos, len;
835 
836 	/*
837 	 * Fill the buffer with 0xff first except the full page transfer.
838 	 * This simplifies the logic.
839 	 */
840 	if (!buf || !oob_required)
841 		memset(tmp_buf, 0xff, size);
842 
843 	/* Arrange the buffer for syndrome payload/ecc layout */
844 	if (buf) {
845 		for (i = 0; i < ecc_steps; i++) {
846 			pos = i * (ecc_size + ecc_bytes);
847 			len = ecc_size;
848 
849 			if (pos >= writesize)
850 				pos += oob_skip;
851 			else if (pos + len > writesize)
852 				len = writesize - pos;
853 
854 			memcpy(tmp_buf + pos, buf, len);
855 			buf += len;
856 			if (len < ecc_size) {
857 				len = ecc_size - len;
858 				memcpy(tmp_buf + writesize + oob_skip, buf,
859 				       len);
860 				buf += len;
861 			}
862 		}
863 	}
864 
865 	if (oob_required) {
866 		const uint8_t *oob = chip->oob_poi;
867 
868 		/* BBM at the beginning of the OOB area */
869 		memcpy(tmp_buf + writesize, oob, oob_skip);
870 		oob += oob_skip;
871 
872 		/* OOB ECC */
873 		for (i = 0; i < ecc_steps; i++) {
874 			pos = ecc_size + i * (ecc_size + ecc_bytes);
875 			len = ecc_bytes;
876 
877 			if (pos >= writesize)
878 				pos += oob_skip;
879 			else if (pos + len > writesize)
880 				len = writesize - pos;
881 
882 			memcpy(tmp_buf + pos, oob, len);
883 			oob += len;
884 			if (len < ecc_bytes) {
885 				len = ecc_bytes - len;
886 				memcpy(tmp_buf + writesize + oob_skip, oob,
887 				       len);
888 				oob += len;
889 			}
890 		}
891 
892 		/* OOB free */
893 		len = oobsize - (oob - chip->oob_poi);
894 		memcpy(tmp_buf + size - len, oob, len);
895 	}
896 
897 	return denali_data_xfer(denali, tmp_buf, size, page, 1, 1);
898 }
899 
900 static int denali_write_page(struct mtd_info *mtd, struct nand_chip *chip,
901 			     const uint8_t *buf, int oob_required, int page)
902 {
903 	struct denali_nand_info *denali = mtd_to_denali(mtd);
904 
905 	return denali_data_xfer(denali, (void *)buf, mtd->writesize,
906 				page, 0, 1);
907 }
908 
909 static void denali_select_chip(struct mtd_info *mtd, int chip)
910 {
911 	struct denali_nand_info *denali = mtd_to_denali(mtd);
912 
913 	denali->active_bank = chip;
914 }
915 
916 static int denali_waitfunc(struct mtd_info *mtd, struct nand_chip *chip)
917 {
918 	struct denali_nand_info *denali = mtd_to_denali(mtd);
919 	uint32_t irq_status;
920 
921 	/* R/B# pin transitioned from low to high? */
922 	irq_status = denali_wait_for_irq(denali, INTR__INT_ACT);
923 
924 	return irq_status & INTR__INT_ACT ? 0 : NAND_STATUS_FAIL;
925 }
926 
927 static int denali_erase(struct mtd_info *mtd, int page)
928 {
929 	struct denali_nand_info *denali = mtd_to_denali(mtd);
930 	uint32_t irq_status;
931 
932 	denali_reset_irq(denali);
933 
934 	denali->host_write(denali, DENALI_MAP10 | DENALI_BANK(denali) | page,
935 			   DENALI_ERASE);
936 
937 	/* wait for erase to complete or failure to occur */
938 	irq_status = denali_wait_for_irq(denali,
939 					 INTR__ERASE_COMP | INTR__ERASE_FAIL);
940 
941 	return irq_status & INTR__ERASE_COMP ? 0 : -EIO;
942 }
943 
944 static int denali_setup_data_interface(struct mtd_info *mtd, int chipnr,
945 				       const struct nand_data_interface *conf)
946 {
947 	struct denali_nand_info *denali = mtd_to_denali(mtd);
948 	const struct nand_sdr_timings *timings;
949 	unsigned long t_x, mult_x;
950 	int acc_clks, re_2_we, re_2_re, we_2_re, addr_2_data;
951 	int rdwr_en_lo, rdwr_en_hi, rdwr_en_lo_hi, cs_setup;
952 	int addr_2_data_mask;
953 	uint32_t tmp;
954 
955 	timings = nand_get_sdr_timings(conf);
956 	if (IS_ERR(timings))
957 		return PTR_ERR(timings);
958 
959 	/* clk_x period in picoseconds */
960 	t_x = DIV_ROUND_DOWN_ULL(1000000000000ULL, denali->clk_x_rate);
961 	if (!t_x)
962 		return -EINVAL;
963 
964 	/*
965 	 * The bus interface clock, clk_x, is phase aligned with the core clock.
966 	 * The clk_x is an integral multiple N of the core clk.  The value N is
967 	 * configured at IP delivery time, and its available value is 4, 5, 6.
968 	 */
969 	mult_x = DIV_ROUND_CLOSEST_ULL(denali->clk_x_rate, denali->clk_rate);
970 	if (mult_x < 4 || mult_x > 6)
971 		return -EINVAL;
972 
973 	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
974 		return 0;
975 
976 	/* tREA -> ACC_CLKS */
977 	acc_clks = DIV_ROUND_UP(timings->tREA_max, t_x);
978 	acc_clks = min_t(int, acc_clks, ACC_CLKS__VALUE);
979 
980 	tmp = ioread32(denali->reg + ACC_CLKS);
981 	tmp &= ~ACC_CLKS__VALUE;
982 	tmp |= FIELD_PREP(ACC_CLKS__VALUE, acc_clks);
983 	iowrite32(tmp, denali->reg + ACC_CLKS);
984 
985 	/* tRWH -> RE_2_WE */
986 	re_2_we = DIV_ROUND_UP(timings->tRHW_min, t_x);
987 	re_2_we = min_t(int, re_2_we, RE_2_WE__VALUE);
988 
989 	tmp = ioread32(denali->reg + RE_2_WE);
990 	tmp &= ~RE_2_WE__VALUE;
991 	tmp |= FIELD_PREP(RE_2_WE__VALUE, re_2_we);
992 	iowrite32(tmp, denali->reg + RE_2_WE);
993 
994 	/* tRHZ -> RE_2_RE */
995 	re_2_re = DIV_ROUND_UP(timings->tRHZ_max, t_x);
996 	re_2_re = min_t(int, re_2_re, RE_2_RE__VALUE);
997 
998 	tmp = ioread32(denali->reg + RE_2_RE);
999 	tmp &= ~RE_2_RE__VALUE;
1000 	tmp |= FIELD_PREP(RE_2_RE__VALUE, re_2_re);
1001 	iowrite32(tmp, denali->reg + RE_2_RE);
1002 
1003 	/*
1004 	 * tCCS, tWHR -> WE_2_RE
1005 	 *
1006 	 * With WE_2_RE properly set, the Denali controller automatically takes
1007 	 * care of the delay; the driver need not set NAND_WAIT_TCCS.
1008 	 */
1009 	we_2_re = DIV_ROUND_UP(max(timings->tCCS_min, timings->tWHR_min), t_x);
1010 	we_2_re = min_t(int, we_2_re, TWHR2_AND_WE_2_RE__WE_2_RE);
1011 
1012 	tmp = ioread32(denali->reg + TWHR2_AND_WE_2_RE);
1013 	tmp &= ~TWHR2_AND_WE_2_RE__WE_2_RE;
1014 	tmp |= FIELD_PREP(TWHR2_AND_WE_2_RE__WE_2_RE, we_2_re);
1015 	iowrite32(tmp, denali->reg + TWHR2_AND_WE_2_RE);
1016 
1017 	/* tADL -> ADDR_2_DATA */
1018 
1019 	/* for older versions, ADDR_2_DATA is only 6 bit wide */
1020 	addr_2_data_mask = TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
1021 	if (denali->revision < 0x0501)
1022 		addr_2_data_mask >>= 1;
1023 
1024 	addr_2_data = DIV_ROUND_UP(timings->tADL_min, t_x);
1025 	addr_2_data = min_t(int, addr_2_data, addr_2_data_mask);
1026 
1027 	tmp = ioread32(denali->reg + TCWAW_AND_ADDR_2_DATA);
1028 	tmp &= ~TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
1029 	tmp |= FIELD_PREP(TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA, addr_2_data);
1030 	iowrite32(tmp, denali->reg + TCWAW_AND_ADDR_2_DATA);
1031 
1032 	/* tREH, tWH -> RDWR_EN_HI_CNT */
1033 	rdwr_en_hi = DIV_ROUND_UP(max(timings->tREH_min, timings->tWH_min),
1034 				  t_x);
1035 	rdwr_en_hi = min_t(int, rdwr_en_hi, RDWR_EN_HI_CNT__VALUE);
1036 
1037 	tmp = ioread32(denali->reg + RDWR_EN_HI_CNT);
1038 	tmp &= ~RDWR_EN_HI_CNT__VALUE;
1039 	tmp |= FIELD_PREP(RDWR_EN_HI_CNT__VALUE, rdwr_en_hi);
1040 	iowrite32(tmp, denali->reg + RDWR_EN_HI_CNT);
1041 
1042 	/* tRP, tWP -> RDWR_EN_LO_CNT */
1043 	rdwr_en_lo = DIV_ROUND_UP(max(timings->tRP_min, timings->tWP_min), t_x);
1044 	rdwr_en_lo_hi = DIV_ROUND_UP(max(timings->tRC_min, timings->tWC_min),
1045 				     t_x);
1046 	rdwr_en_lo_hi = max_t(int, rdwr_en_lo_hi, mult_x);
1047 	rdwr_en_lo = max(rdwr_en_lo, rdwr_en_lo_hi - rdwr_en_hi);
1048 	rdwr_en_lo = min_t(int, rdwr_en_lo, RDWR_EN_LO_CNT__VALUE);
1049 
1050 	tmp = ioread32(denali->reg + RDWR_EN_LO_CNT);
1051 	tmp &= ~RDWR_EN_LO_CNT__VALUE;
1052 	tmp |= FIELD_PREP(RDWR_EN_LO_CNT__VALUE, rdwr_en_lo);
1053 	iowrite32(tmp, denali->reg + RDWR_EN_LO_CNT);
1054 
1055 	/* tCS, tCEA -> CS_SETUP_CNT */
1056 	cs_setup = max3((int)DIV_ROUND_UP(timings->tCS_min, t_x) - rdwr_en_lo,
1057 			(int)DIV_ROUND_UP(timings->tCEA_max, t_x) - acc_clks,
1058 			0);
1059 	cs_setup = min_t(int, cs_setup, CS_SETUP_CNT__VALUE);
1060 
1061 	tmp = ioread32(denali->reg + CS_SETUP_CNT);
1062 	tmp &= ~CS_SETUP_CNT__VALUE;
1063 	tmp |= FIELD_PREP(CS_SETUP_CNT__VALUE, cs_setup);
1064 	iowrite32(tmp, denali->reg + CS_SETUP_CNT);
1065 
1066 	return 0;
1067 }
1068 
1069 static void denali_reset_banks(struct denali_nand_info *denali)
1070 {
1071 	u32 irq_status;
1072 	int i;
1073 
1074 	for (i = 0; i < denali->max_banks; i++) {
1075 		denali->active_bank = i;
1076 
1077 		denali_reset_irq(denali);
1078 
1079 		iowrite32(DEVICE_RESET__BANK(i),
1080 			  denali->reg + DEVICE_RESET);
1081 
1082 		irq_status = denali_wait_for_irq(denali,
1083 			INTR__RST_COMP | INTR__INT_ACT | INTR__TIME_OUT);
1084 		if (!(irq_status & INTR__INT_ACT))
1085 			break;
1086 	}
1087 
1088 	dev_dbg(denali->dev, "%d chips connected\n", i);
1089 	denali->max_banks = i;
1090 }
1091 
1092 static void denali_hw_init(struct denali_nand_info *denali)
1093 {
1094 	/*
1095 	 * The REVISION register may not be reliable.  Platforms are allowed to
1096 	 * override it.
1097 	 */
1098 	if (!denali->revision)
1099 		denali->revision = swab16(ioread32(denali->reg + REVISION));
1100 
1101 	/*
1102 	 * tell driver how many bit controller will skip before
1103 	 * writing ECC code in OOB, this register may be already
1104 	 * set by firmware. So we read this value out.
1105 	 * if this value is 0, just let it be.
1106 	 */
1107 	denali->oob_skip_bytes = ioread32(denali->reg + SPARE_AREA_SKIP_BYTES);
1108 	denali_detect_max_banks(denali);
1109 	iowrite32(0x0F, denali->reg + RB_PIN_ENABLED);
1110 	iowrite32(CHIP_EN_DONT_CARE__FLAG, denali->reg + CHIP_ENABLE_DONT_CARE);
1111 
1112 	iowrite32(0xffff, denali->reg + SPARE_AREA_MARKER);
1113 }
1114 
1115 int denali_calc_ecc_bytes(int step_size, int strength)
1116 {
1117 	/* BCH code.  Denali requires ecc.bytes to be multiple of 2 */
1118 	return DIV_ROUND_UP(strength * fls(step_size * 8), 16) * 2;
1119 }
1120 EXPORT_SYMBOL(denali_calc_ecc_bytes);
1121 
1122 static int denali_ooblayout_ecc(struct mtd_info *mtd, int section,
1123 				struct mtd_oob_region *oobregion)
1124 {
1125 	struct denali_nand_info *denali = mtd_to_denali(mtd);
1126 	struct nand_chip *chip = mtd_to_nand(mtd);
1127 
1128 	if (section)
1129 		return -ERANGE;
1130 
1131 	oobregion->offset = denali->oob_skip_bytes;
1132 	oobregion->length = chip->ecc.total;
1133 
1134 	return 0;
1135 }
1136 
1137 static int denali_ooblayout_free(struct mtd_info *mtd, int section,
1138 				 struct mtd_oob_region *oobregion)
1139 {
1140 	struct denali_nand_info *denali = mtd_to_denali(mtd);
1141 	struct nand_chip *chip = mtd_to_nand(mtd);
1142 
1143 	if (section)
1144 		return -ERANGE;
1145 
1146 	oobregion->offset = chip->ecc.total + denali->oob_skip_bytes;
1147 	oobregion->length = mtd->oobsize - oobregion->offset;
1148 
1149 	return 0;
1150 }
1151 
1152 static const struct mtd_ooblayout_ops denali_ooblayout_ops = {
1153 	.ecc = denali_ooblayout_ecc,
1154 	.free = denali_ooblayout_free,
1155 };
1156 
1157 static int denali_multidev_fixup(struct denali_nand_info *denali)
1158 {
1159 	struct nand_chip *chip = &denali->nand;
1160 	struct mtd_info *mtd = nand_to_mtd(chip);
1161 
1162 	/*
1163 	 * Support for multi device:
1164 	 * When the IP configuration is x16 capable and two x8 chips are
1165 	 * connected in parallel, DEVICES_CONNECTED should be set to 2.
1166 	 * In this case, the core framework knows nothing about this fact,
1167 	 * so we should tell it the _logical_ pagesize and anything necessary.
1168 	 */
1169 	denali->devs_per_cs = ioread32(denali->reg + DEVICES_CONNECTED);
1170 
1171 	/*
1172 	 * On some SoCs, DEVICES_CONNECTED is not auto-detected.
1173 	 * For those, DEVICES_CONNECTED is left to 0.  Set 1 if it is the case.
1174 	 */
1175 	if (denali->devs_per_cs == 0) {
1176 		denali->devs_per_cs = 1;
1177 		iowrite32(1, denali->reg + DEVICES_CONNECTED);
1178 	}
1179 
1180 	if (denali->devs_per_cs == 1)
1181 		return 0;
1182 
1183 	if (denali->devs_per_cs != 2) {
1184 		dev_err(denali->dev, "unsupported number of devices %d\n",
1185 			denali->devs_per_cs);
1186 		return -EINVAL;
1187 	}
1188 
1189 	/* 2 chips in parallel */
1190 	mtd->size <<= 1;
1191 	mtd->erasesize <<= 1;
1192 	mtd->writesize <<= 1;
1193 	mtd->oobsize <<= 1;
1194 	chip->chipsize <<= 1;
1195 	chip->page_shift += 1;
1196 	chip->phys_erase_shift += 1;
1197 	chip->bbt_erase_shift += 1;
1198 	chip->chip_shift += 1;
1199 	chip->pagemask <<= 1;
1200 	chip->ecc.size <<= 1;
1201 	chip->ecc.bytes <<= 1;
1202 	chip->ecc.strength <<= 1;
1203 	denali->oob_skip_bytes <<= 1;
1204 
1205 	return 0;
1206 }
1207 
1208 static int denali_attach_chip(struct nand_chip *chip)
1209 {
1210 	struct mtd_info *mtd = nand_to_mtd(chip);
1211 	struct denali_nand_info *denali = mtd_to_denali(mtd);
1212 	int ret;
1213 
1214 	if (ioread32(denali->reg + FEATURES) & FEATURES__DMA)
1215 		denali->dma_avail = 1;
1216 
1217 	if (denali->dma_avail) {
1218 		int dma_bit = denali->caps & DENALI_CAP_DMA_64BIT ? 64 : 32;
1219 
1220 		ret = dma_set_mask(denali->dev, DMA_BIT_MASK(dma_bit));
1221 		if (ret) {
1222 			dev_info(denali->dev,
1223 				 "Failed to set DMA mask. Disabling DMA.\n");
1224 			denali->dma_avail = 0;
1225 		}
1226 	}
1227 
1228 	if (denali->dma_avail) {
1229 		chip->options |= NAND_USE_BOUNCE_BUFFER;
1230 		chip->buf_align = 16;
1231 		if (denali->caps & DENALI_CAP_DMA_64BIT)
1232 			denali->setup_dma = denali_setup_dma64;
1233 		else
1234 			denali->setup_dma = denali_setup_dma32;
1235 	}
1236 
1237 	chip->bbt_options |= NAND_BBT_USE_FLASH;
1238 	chip->bbt_options |= NAND_BBT_NO_OOB;
1239 	chip->ecc.mode = NAND_ECC_HW_SYNDROME;
1240 	chip->options |= NAND_NO_SUBPAGE_WRITE;
1241 
1242 	ret = nand_ecc_choose_conf(chip, denali->ecc_caps,
1243 				   mtd->oobsize - denali->oob_skip_bytes);
1244 	if (ret) {
1245 		dev_err(denali->dev, "Failed to setup ECC settings.\n");
1246 		return ret;
1247 	}
1248 
1249 	dev_dbg(denali->dev,
1250 		"chosen ECC settings: step=%d, strength=%d, bytes=%d\n",
1251 		chip->ecc.size, chip->ecc.strength, chip->ecc.bytes);
1252 
1253 	iowrite32(FIELD_PREP(ECC_CORRECTION__ERASE_THRESHOLD, 1) |
1254 		  FIELD_PREP(ECC_CORRECTION__VALUE, chip->ecc.strength),
1255 		  denali->reg + ECC_CORRECTION);
1256 	iowrite32(mtd->erasesize / mtd->writesize,
1257 		  denali->reg + PAGES_PER_BLOCK);
1258 	iowrite32(chip->options & NAND_BUSWIDTH_16 ? 1 : 0,
1259 		  denali->reg + DEVICE_WIDTH);
1260 	iowrite32(chip->options & NAND_ROW_ADDR_3 ? 0 : TWO_ROW_ADDR_CYCLES__FLAG,
1261 		  denali->reg + TWO_ROW_ADDR_CYCLES);
1262 	iowrite32(mtd->writesize, denali->reg + DEVICE_MAIN_AREA_SIZE);
1263 	iowrite32(mtd->oobsize, denali->reg + DEVICE_SPARE_AREA_SIZE);
1264 
1265 	iowrite32(chip->ecc.size, denali->reg + CFG_DATA_BLOCK_SIZE);
1266 	iowrite32(chip->ecc.size, denali->reg + CFG_LAST_DATA_BLOCK_SIZE);
1267 	/* chip->ecc.steps is set by nand_scan_tail(); not available here */
1268 	iowrite32(mtd->writesize / chip->ecc.size,
1269 		  denali->reg + CFG_NUM_DATA_BLOCKS);
1270 
1271 	mtd_set_ooblayout(mtd, &denali_ooblayout_ops);
1272 
1273 	if (chip->options & NAND_BUSWIDTH_16) {
1274 		chip->read_buf = denali_read_buf16;
1275 		chip->write_buf = denali_write_buf16;
1276 	} else {
1277 		chip->read_buf = denali_read_buf;
1278 		chip->write_buf = denali_write_buf;
1279 	}
1280 	chip->ecc.read_page = denali_read_page;
1281 	chip->ecc.read_page_raw = denali_read_page_raw;
1282 	chip->ecc.write_page = denali_write_page;
1283 	chip->ecc.write_page_raw = denali_write_page_raw;
1284 	chip->ecc.read_oob = denali_read_oob;
1285 	chip->ecc.write_oob = denali_write_oob;
1286 	chip->erase = denali_erase;
1287 
1288 	ret = denali_multidev_fixup(denali);
1289 	if (ret)
1290 		return ret;
1291 
1292 	/*
1293 	 * This buffer is DMA-mapped by denali_{read,write}_page_raw.  Do not
1294 	 * use devm_kmalloc() because the memory allocated by devm_ does not
1295 	 * guarantee DMA-safe alignment.
1296 	 */
1297 	denali->buf = kmalloc(mtd->writesize + mtd->oobsize, GFP_KERNEL);
1298 	if (!denali->buf)
1299 		return -ENOMEM;
1300 
1301 	return 0;
1302 }
1303 
1304 static void denali_detach_chip(struct nand_chip *chip)
1305 {
1306 	struct mtd_info *mtd = nand_to_mtd(chip);
1307 	struct denali_nand_info *denali = mtd_to_denali(mtd);
1308 
1309 	kfree(denali->buf);
1310 }
1311 
1312 static const struct nand_controller_ops denali_controller_ops = {
1313 	.attach_chip = denali_attach_chip,
1314 	.detach_chip = denali_detach_chip,
1315 };
1316 
1317 int denali_init(struct denali_nand_info *denali)
1318 {
1319 	struct nand_chip *chip = &denali->nand;
1320 	struct mtd_info *mtd = nand_to_mtd(chip);
1321 	u32 features = ioread32(denali->reg + FEATURES);
1322 	int ret;
1323 
1324 	mtd->dev.parent = denali->dev;
1325 	denali_hw_init(denali);
1326 
1327 	init_completion(&denali->complete);
1328 	spin_lock_init(&denali->irq_lock);
1329 
1330 	denali_clear_irq_all(denali);
1331 
1332 	ret = devm_request_irq(denali->dev, denali->irq, denali_isr,
1333 			       IRQF_SHARED, DENALI_NAND_NAME, denali);
1334 	if (ret) {
1335 		dev_err(denali->dev, "Unable to request IRQ\n");
1336 		return ret;
1337 	}
1338 
1339 	denali_enable_irq(denali);
1340 	denali_reset_banks(denali);
1341 
1342 	denali->active_bank = DENALI_INVALID_BANK;
1343 
1344 	nand_set_flash_node(chip, denali->dev->of_node);
1345 	/* Fallback to the default name if DT did not give "label" property */
1346 	if (!mtd->name)
1347 		mtd->name = "denali-nand";
1348 
1349 	chip->select_chip = denali_select_chip;
1350 	chip->read_byte = denali_read_byte;
1351 	chip->write_byte = denali_write_byte;
1352 	chip->read_word = denali_read_word;
1353 	chip->cmd_ctrl = denali_cmd_ctrl;
1354 	chip->dev_ready = denali_dev_ready;
1355 	chip->waitfunc = denali_waitfunc;
1356 
1357 	if (features & FEATURES__INDEX_ADDR) {
1358 		denali->host_read = denali_indexed_read;
1359 		denali->host_write = denali_indexed_write;
1360 	} else {
1361 		denali->host_read = denali_direct_read;
1362 		denali->host_write = denali_direct_write;
1363 	}
1364 
1365 	/* clk rate info is needed for setup_data_interface */
1366 	if (denali->clk_rate && denali->clk_x_rate)
1367 		chip->setup_data_interface = denali_setup_data_interface;
1368 
1369 	chip->dummy_controller.ops = &denali_controller_ops;
1370 	ret = nand_scan(mtd, denali->max_banks);
1371 	if (ret)
1372 		goto disable_irq;
1373 
1374 	ret = mtd_device_register(mtd, NULL, 0);
1375 	if (ret) {
1376 		dev_err(denali->dev, "Failed to register MTD: %d\n", ret);
1377 		goto cleanup_nand;
1378 	}
1379 
1380 	return 0;
1381 
1382 cleanup_nand:
1383 	nand_cleanup(chip);
1384 disable_irq:
1385 	denali_disable_irq(denali);
1386 
1387 	return ret;
1388 }
1389 EXPORT_SYMBOL(denali_init);
1390 
1391 void denali_remove(struct denali_nand_info *denali)
1392 {
1393 	struct mtd_info *mtd = nand_to_mtd(&denali->nand);
1394 
1395 	nand_release(mtd);
1396 	denali_disable_irq(denali);
1397 }
1398 EXPORT_SYMBOL(denali_remove);
1399