xref: /openbmc/linux/drivers/mtd/nand/raw/denali.c (revision 33fb626b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * NAND Flash Controller Device Driver
4  * Copyright © 2009-2010, Intel Corporation and its suppliers.
5  *
6  * Copyright (c) 2017-2019 Socionext Inc.
7  *   Reworked by Masahiro Yamada <yamada.masahiro@socionext.com>
8  */
9 
10 #include <linux/bitfield.h>
11 #include <linux/completion.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/rawnand.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 
21 #include "denali.h"
22 
23 #define DENALI_NAND_NAME    "denali-nand"
24 
25 /* for Indexed Addressing */
26 #define DENALI_INDEXED_CTRL	0x00
27 #define DENALI_INDEXED_DATA	0x10
28 
29 #define DENALI_MAP00		(0 << 26)	/* direct access to buffer */
30 #define DENALI_MAP01		(1 << 26)	/* read/write pages in PIO */
31 #define DENALI_MAP10		(2 << 26)	/* high-level control plane */
32 #define DENALI_MAP11		(3 << 26)	/* direct controller access */
33 
34 /* MAP11 access cycle type */
35 #define DENALI_MAP11_CMD	((DENALI_MAP11) | 0)	/* command cycle */
36 #define DENALI_MAP11_ADDR	((DENALI_MAP11) | 1)	/* address cycle */
37 #define DENALI_MAP11_DATA	((DENALI_MAP11) | 2)	/* data cycle */
38 
39 #define DENALI_BANK(denali)	((denali)->active_bank << 24)
40 
41 #define DENALI_INVALID_BANK	-1
42 
43 static struct denali_chip *to_denali_chip(struct nand_chip *chip)
44 {
45 	return container_of(chip, struct denali_chip, chip);
46 }
47 
48 static struct denali_controller *to_denali_controller(struct nand_chip *chip)
49 {
50 	return container_of(chip->controller, struct denali_controller,
51 			    controller);
52 }
53 
54 /*
55  * Direct Addressing - the slave address forms the control information (command
56  * type, bank, block, and page address).  The slave data is the actual data to
57  * be transferred.  This mode requires 28 bits of address region allocated.
58  */
59 static u32 denali_direct_read(struct denali_controller *denali, u32 addr)
60 {
61 	return ioread32(denali->host + addr);
62 }
63 
64 static void denali_direct_write(struct denali_controller *denali, u32 addr,
65 				u32 data)
66 {
67 	iowrite32(data, denali->host + addr);
68 }
69 
70 /*
71  * Indexed Addressing - address translation module intervenes in passing the
72  * control information.  This mode reduces the required address range.  The
73  * control information and transferred data are latched by the registers in
74  * the translation module.
75  */
76 static u32 denali_indexed_read(struct denali_controller *denali, u32 addr)
77 {
78 	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
79 	return ioread32(denali->host + DENALI_INDEXED_DATA);
80 }
81 
82 static void denali_indexed_write(struct denali_controller *denali, u32 addr,
83 				 u32 data)
84 {
85 	iowrite32(addr, denali->host + DENALI_INDEXED_CTRL);
86 	iowrite32(data, denali->host + DENALI_INDEXED_DATA);
87 }
88 
89 static void denali_enable_irq(struct denali_controller *denali)
90 {
91 	int i;
92 
93 	for (i = 0; i < denali->nbanks; i++)
94 		iowrite32(U32_MAX, denali->reg + INTR_EN(i));
95 	iowrite32(GLOBAL_INT_EN_FLAG, denali->reg + GLOBAL_INT_ENABLE);
96 }
97 
98 static void denali_disable_irq(struct denali_controller *denali)
99 {
100 	int i;
101 
102 	for (i = 0; i < denali->nbanks; i++)
103 		iowrite32(0, denali->reg + INTR_EN(i));
104 	iowrite32(0, denali->reg + GLOBAL_INT_ENABLE);
105 }
106 
107 static void denali_clear_irq(struct denali_controller *denali,
108 			     int bank, u32 irq_status)
109 {
110 	/* write one to clear bits */
111 	iowrite32(irq_status, denali->reg + INTR_STATUS(bank));
112 }
113 
114 static void denali_clear_irq_all(struct denali_controller *denali)
115 {
116 	int i;
117 
118 	for (i = 0; i < denali->nbanks; i++)
119 		denali_clear_irq(denali, i, U32_MAX);
120 }
121 
122 static irqreturn_t denali_isr(int irq, void *dev_id)
123 {
124 	struct denali_controller *denali = dev_id;
125 	irqreturn_t ret = IRQ_NONE;
126 	u32 irq_status;
127 	int i;
128 
129 	spin_lock(&denali->irq_lock);
130 
131 	for (i = 0; i < denali->nbanks; i++) {
132 		irq_status = ioread32(denali->reg + INTR_STATUS(i));
133 		if (irq_status)
134 			ret = IRQ_HANDLED;
135 
136 		denali_clear_irq(denali, i, irq_status);
137 
138 		if (i != denali->active_bank)
139 			continue;
140 
141 		denali->irq_status |= irq_status;
142 
143 		if (denali->irq_status & denali->irq_mask)
144 			complete(&denali->complete);
145 	}
146 
147 	spin_unlock(&denali->irq_lock);
148 
149 	return ret;
150 }
151 
152 static void denali_reset_irq(struct denali_controller *denali)
153 {
154 	unsigned long flags;
155 
156 	spin_lock_irqsave(&denali->irq_lock, flags);
157 	denali->irq_status = 0;
158 	denali->irq_mask = 0;
159 	spin_unlock_irqrestore(&denali->irq_lock, flags);
160 }
161 
162 static u32 denali_wait_for_irq(struct denali_controller *denali, u32 irq_mask)
163 {
164 	unsigned long time_left, flags;
165 	u32 irq_status;
166 
167 	spin_lock_irqsave(&denali->irq_lock, flags);
168 
169 	irq_status = denali->irq_status;
170 
171 	if (irq_mask & irq_status) {
172 		/* return immediately if the IRQ has already happened. */
173 		spin_unlock_irqrestore(&denali->irq_lock, flags);
174 		return irq_status;
175 	}
176 
177 	denali->irq_mask = irq_mask;
178 	reinit_completion(&denali->complete);
179 	spin_unlock_irqrestore(&denali->irq_lock, flags);
180 
181 	time_left = wait_for_completion_timeout(&denali->complete,
182 						msecs_to_jiffies(1000));
183 	if (!time_left) {
184 		dev_err(denali->dev, "timeout while waiting for irq 0x%x\n",
185 			irq_mask);
186 		return 0;
187 	}
188 
189 	return denali->irq_status;
190 }
191 
192 static void denali_select_target(struct nand_chip *chip, int cs)
193 {
194 	struct denali_controller *denali = to_denali_controller(chip);
195 	struct denali_chip_sel *sel = &to_denali_chip(chip)->sels[cs];
196 	struct mtd_info *mtd = nand_to_mtd(chip);
197 
198 	denali->active_bank = sel->bank;
199 
200 	iowrite32(1 << (chip->phys_erase_shift - chip->page_shift),
201 		  denali->reg + PAGES_PER_BLOCK);
202 	iowrite32(chip->options & NAND_BUSWIDTH_16 ? 1 : 0,
203 		  denali->reg + DEVICE_WIDTH);
204 	iowrite32(mtd->writesize, denali->reg + DEVICE_MAIN_AREA_SIZE);
205 	iowrite32(mtd->oobsize, denali->reg + DEVICE_SPARE_AREA_SIZE);
206 	iowrite32(chip->options & NAND_ROW_ADDR_3 ?
207 		  0 : TWO_ROW_ADDR_CYCLES__FLAG,
208 		  denali->reg + TWO_ROW_ADDR_CYCLES);
209 	iowrite32(FIELD_PREP(ECC_CORRECTION__ERASE_THRESHOLD, 1) |
210 		  FIELD_PREP(ECC_CORRECTION__VALUE, chip->ecc.strength),
211 		  denali->reg + ECC_CORRECTION);
212 	iowrite32(chip->ecc.size, denali->reg + CFG_DATA_BLOCK_SIZE);
213 	iowrite32(chip->ecc.size, denali->reg + CFG_LAST_DATA_BLOCK_SIZE);
214 	iowrite32(chip->ecc.steps, denali->reg + CFG_NUM_DATA_BLOCKS);
215 
216 	if (chip->options & NAND_KEEP_TIMINGS)
217 		return;
218 
219 	/* update timing registers unless NAND_KEEP_TIMINGS is set */
220 	iowrite32(sel->hwhr2_and_we_2_re, denali->reg + TWHR2_AND_WE_2_RE);
221 	iowrite32(sel->tcwaw_and_addr_2_data,
222 		  denali->reg + TCWAW_AND_ADDR_2_DATA);
223 	iowrite32(sel->re_2_we, denali->reg + RE_2_WE);
224 	iowrite32(sel->acc_clks, denali->reg + ACC_CLKS);
225 	iowrite32(sel->rdwr_en_lo_cnt, denali->reg + RDWR_EN_LO_CNT);
226 	iowrite32(sel->rdwr_en_hi_cnt, denali->reg + RDWR_EN_HI_CNT);
227 	iowrite32(sel->cs_setup_cnt, denali->reg + CS_SETUP_CNT);
228 	iowrite32(sel->re_2_re, denali->reg + RE_2_RE);
229 }
230 
231 static int denali_change_column(struct nand_chip *chip, unsigned int offset,
232 				void *buf, unsigned int len, bool write)
233 {
234 	if (write)
235 		return nand_change_write_column_op(chip, offset, buf, len,
236 						   false);
237 	else
238 		return nand_change_read_column_op(chip, offset, buf, len,
239 						  false);
240 }
241 
242 static int denali_payload_xfer(struct nand_chip *chip, void *buf, bool write)
243 {
244 	struct denali_controller *denali = to_denali_controller(chip);
245 	struct mtd_info *mtd = nand_to_mtd(chip);
246 	struct nand_ecc_ctrl *ecc = &chip->ecc;
247 	int writesize = mtd->writesize;
248 	int oob_skip = denali->oob_skip_bytes;
249 	int ret, i, pos, len;
250 
251 	for (i = 0; i < ecc->steps; i++) {
252 		pos = i * (ecc->size + ecc->bytes);
253 		len = ecc->size;
254 
255 		if (pos >= writesize) {
256 			pos += oob_skip;
257 		} else if (pos + len > writesize) {
258 			/* This chunk overwraps the BBM area. Must be split */
259 			ret = denali_change_column(chip, pos, buf,
260 						   writesize - pos, write);
261 			if (ret)
262 				return ret;
263 
264 			buf += writesize - pos;
265 			len -= writesize - pos;
266 			pos = writesize + oob_skip;
267 		}
268 
269 		ret = denali_change_column(chip, pos, buf, len, write);
270 		if (ret)
271 			return ret;
272 
273 		buf += len;
274 	}
275 
276 	return 0;
277 }
278 
279 static int denali_oob_xfer(struct nand_chip *chip, void *buf, bool write)
280 {
281 	struct denali_controller *denali = to_denali_controller(chip);
282 	struct mtd_info *mtd = nand_to_mtd(chip);
283 	struct nand_ecc_ctrl *ecc = &chip->ecc;
284 	int writesize = mtd->writesize;
285 	int oobsize = mtd->oobsize;
286 	int oob_skip = denali->oob_skip_bytes;
287 	int ret, i, pos, len;
288 
289 	/* BBM at the beginning of the OOB area */
290 	ret = denali_change_column(chip, writesize, buf, oob_skip, write);
291 	if (ret)
292 		return ret;
293 
294 	buf += oob_skip;
295 
296 	for (i = 0; i < ecc->steps; i++) {
297 		pos = ecc->size + i * (ecc->size + ecc->bytes);
298 
299 		if (i == ecc->steps - 1)
300 			/* The last chunk includes OOB free */
301 			len = writesize + oobsize - pos - oob_skip;
302 		else
303 			len = ecc->bytes;
304 
305 		if (pos >= writesize) {
306 			pos += oob_skip;
307 		} else if (pos + len > writesize) {
308 			/* This chunk overwraps the BBM area. Must be split */
309 			ret = denali_change_column(chip, pos, buf,
310 						   writesize - pos, write);
311 			if (ret)
312 				return ret;
313 
314 			buf += writesize - pos;
315 			len -= writesize - pos;
316 			pos = writesize + oob_skip;
317 		}
318 
319 		ret = denali_change_column(chip, pos, buf, len, write);
320 		if (ret)
321 			return ret;
322 
323 		buf += len;
324 	}
325 
326 	return 0;
327 }
328 
329 static int denali_read_raw(struct nand_chip *chip, void *buf, void *oob_buf,
330 			   int page)
331 {
332 	int ret;
333 
334 	if (!buf && !oob_buf)
335 		return -EINVAL;
336 
337 	ret = nand_read_page_op(chip, page, 0, NULL, 0);
338 	if (ret)
339 		return ret;
340 
341 	if (buf) {
342 		ret = denali_payload_xfer(chip, buf, false);
343 		if (ret)
344 			return ret;
345 	}
346 
347 	if (oob_buf) {
348 		ret = denali_oob_xfer(chip, oob_buf, false);
349 		if (ret)
350 			return ret;
351 	}
352 
353 	return 0;
354 }
355 
356 static int denali_write_raw(struct nand_chip *chip, const void *buf,
357 			    const void *oob_buf, int page)
358 {
359 	int ret;
360 
361 	if (!buf && !oob_buf)
362 		return -EINVAL;
363 
364 	ret = nand_prog_page_begin_op(chip, page, 0, NULL, 0);
365 	if (ret)
366 		return ret;
367 
368 	if (buf) {
369 		ret = denali_payload_xfer(chip, (void *)buf, true);
370 		if (ret)
371 			return ret;
372 	}
373 
374 	if (oob_buf) {
375 		ret = denali_oob_xfer(chip, (void *)oob_buf, true);
376 		if (ret)
377 			return ret;
378 	}
379 
380 	return nand_prog_page_end_op(chip);
381 }
382 
383 static int denali_read_page_raw(struct nand_chip *chip, u8 *buf,
384 				int oob_required, int page)
385 {
386 	return denali_read_raw(chip, buf, oob_required ? chip->oob_poi : NULL,
387 			       page);
388 }
389 
390 static int denali_write_page_raw(struct nand_chip *chip, const u8 *buf,
391 				 int oob_required, int page)
392 {
393 	return denali_write_raw(chip, buf, oob_required ? chip->oob_poi : NULL,
394 				page);
395 }
396 
397 static int denali_read_oob(struct nand_chip *chip, int page)
398 {
399 	return denali_read_raw(chip, NULL, chip->oob_poi, page);
400 }
401 
402 static int denali_write_oob(struct nand_chip *chip, int page)
403 {
404 	return denali_write_raw(chip, NULL, chip->oob_poi, page);
405 }
406 
407 static int denali_check_erased_page(struct nand_chip *chip, u8 *buf,
408 				    unsigned long uncor_ecc_flags,
409 				    unsigned int max_bitflips)
410 {
411 	struct denali_controller *denali = to_denali_controller(chip);
412 	struct mtd_ecc_stats *ecc_stats = &nand_to_mtd(chip)->ecc_stats;
413 	struct nand_ecc_ctrl *ecc = &chip->ecc;
414 	u8 *ecc_code = chip->oob_poi + denali->oob_skip_bytes;
415 	int i, stat;
416 
417 	for (i = 0; i < ecc->steps; i++) {
418 		if (!(uncor_ecc_flags & BIT(i)))
419 			continue;
420 
421 		stat = nand_check_erased_ecc_chunk(buf, ecc->size, ecc_code,
422 						   ecc->bytes, NULL, 0,
423 						   ecc->strength);
424 		if (stat < 0) {
425 			ecc_stats->failed++;
426 		} else {
427 			ecc_stats->corrected += stat;
428 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
429 		}
430 
431 		buf += ecc->size;
432 		ecc_code += ecc->bytes;
433 	}
434 
435 	return max_bitflips;
436 }
437 
438 static int denali_hw_ecc_fixup(struct nand_chip *chip,
439 			       unsigned long *uncor_ecc_flags)
440 {
441 	struct denali_controller *denali = to_denali_controller(chip);
442 	struct mtd_ecc_stats *ecc_stats = &nand_to_mtd(chip)->ecc_stats;
443 	int bank = denali->active_bank;
444 	u32 ecc_cor;
445 	unsigned int max_bitflips;
446 
447 	ecc_cor = ioread32(denali->reg + ECC_COR_INFO(bank));
448 	ecc_cor >>= ECC_COR_INFO__SHIFT(bank);
449 
450 	if (ecc_cor & ECC_COR_INFO__UNCOR_ERR) {
451 		/*
452 		 * This flag is set when uncorrectable error occurs at least in
453 		 * one ECC sector.  We can not know "how many sectors", or
454 		 * "which sector(s)".  We need erase-page check for all sectors.
455 		 */
456 		*uncor_ecc_flags = GENMASK(chip->ecc.steps - 1, 0);
457 		return 0;
458 	}
459 
460 	max_bitflips = FIELD_GET(ECC_COR_INFO__MAX_ERRORS, ecc_cor);
461 
462 	/*
463 	 * The register holds the maximum of per-sector corrected bitflips.
464 	 * This is suitable for the return value of the ->read_page() callback.
465 	 * Unfortunately, we can not know the total number of corrected bits in
466 	 * the page.  Increase the stats by max_bitflips. (compromised solution)
467 	 */
468 	ecc_stats->corrected += max_bitflips;
469 
470 	return max_bitflips;
471 }
472 
473 static int denali_sw_ecc_fixup(struct nand_chip *chip,
474 			       unsigned long *uncor_ecc_flags, u8 *buf)
475 {
476 	struct denali_controller *denali = to_denali_controller(chip);
477 	struct mtd_ecc_stats *ecc_stats = &nand_to_mtd(chip)->ecc_stats;
478 	unsigned int ecc_size = chip->ecc.size;
479 	unsigned int bitflips = 0;
480 	unsigned int max_bitflips = 0;
481 	u32 err_addr, err_cor_info;
482 	unsigned int err_byte, err_sector, err_device;
483 	u8 err_cor_value;
484 	unsigned int prev_sector = 0;
485 	u32 irq_status;
486 
487 	denali_reset_irq(denali);
488 
489 	do {
490 		err_addr = ioread32(denali->reg + ECC_ERROR_ADDRESS);
491 		err_sector = FIELD_GET(ECC_ERROR_ADDRESS__SECTOR, err_addr);
492 		err_byte = FIELD_GET(ECC_ERROR_ADDRESS__OFFSET, err_addr);
493 
494 		err_cor_info = ioread32(denali->reg + ERR_CORRECTION_INFO);
495 		err_cor_value = FIELD_GET(ERR_CORRECTION_INFO__BYTE,
496 					  err_cor_info);
497 		err_device = FIELD_GET(ERR_CORRECTION_INFO__DEVICE,
498 				       err_cor_info);
499 
500 		/* reset the bitflip counter when crossing ECC sector */
501 		if (err_sector != prev_sector)
502 			bitflips = 0;
503 
504 		if (err_cor_info & ERR_CORRECTION_INFO__UNCOR) {
505 			/*
506 			 * Check later if this is a real ECC error, or
507 			 * an erased sector.
508 			 */
509 			*uncor_ecc_flags |= BIT(err_sector);
510 		} else if (err_byte < ecc_size) {
511 			/*
512 			 * If err_byte is larger than ecc_size, means error
513 			 * happened in OOB, so we ignore it. It's no need for
514 			 * us to correct it err_device is represented the NAND
515 			 * error bits are happened in if there are more than
516 			 * one NAND connected.
517 			 */
518 			int offset;
519 			unsigned int flips_in_byte;
520 
521 			offset = (err_sector * ecc_size + err_byte) *
522 					denali->devs_per_cs + err_device;
523 
524 			/* correct the ECC error */
525 			flips_in_byte = hweight8(buf[offset] ^ err_cor_value);
526 			buf[offset] ^= err_cor_value;
527 			ecc_stats->corrected += flips_in_byte;
528 			bitflips += flips_in_byte;
529 
530 			max_bitflips = max(max_bitflips, bitflips);
531 		}
532 
533 		prev_sector = err_sector;
534 	} while (!(err_cor_info & ERR_CORRECTION_INFO__LAST_ERR));
535 
536 	/*
537 	 * Once handle all ECC errors, controller will trigger an
538 	 * ECC_TRANSACTION_DONE interrupt.
539 	 */
540 	irq_status = denali_wait_for_irq(denali, INTR__ECC_TRANSACTION_DONE);
541 	if (!(irq_status & INTR__ECC_TRANSACTION_DONE))
542 		return -EIO;
543 
544 	return max_bitflips;
545 }
546 
547 static void denali_setup_dma64(struct denali_controller *denali,
548 			       dma_addr_t dma_addr, int page, bool write)
549 {
550 	u32 mode;
551 	const int page_count = 1;
552 
553 	mode = DENALI_MAP10 | DENALI_BANK(denali) | page;
554 
555 	/* DMA is a three step process */
556 
557 	/*
558 	 * 1. setup transfer type, interrupt when complete,
559 	 *    burst len = 64 bytes, the number of pages
560 	 */
561 	denali->host_write(denali, mode,
562 			   0x01002000 | (64 << 16) |
563 			   (write ? BIT(8) : 0) | page_count);
564 
565 	/* 2. set memory low address */
566 	denali->host_write(denali, mode, lower_32_bits(dma_addr));
567 
568 	/* 3. set memory high address */
569 	denali->host_write(denali, mode, upper_32_bits(dma_addr));
570 }
571 
572 static void denali_setup_dma32(struct denali_controller *denali,
573 			       dma_addr_t dma_addr, int page, bool write)
574 {
575 	u32 mode;
576 	const int page_count = 1;
577 
578 	mode = DENALI_MAP10 | DENALI_BANK(denali);
579 
580 	/* DMA is a four step process */
581 
582 	/* 1. setup transfer type and # of pages */
583 	denali->host_write(denali, mode | page,
584 			   0x2000 | (write ? BIT(8) : 0) | page_count);
585 
586 	/* 2. set memory high address bits 23:8 */
587 	denali->host_write(denali, mode | ((dma_addr >> 16) << 8), 0x2200);
588 
589 	/* 3. set memory low address bits 23:8 */
590 	denali->host_write(denali, mode | ((dma_addr & 0xffff) << 8), 0x2300);
591 
592 	/* 4. interrupt when complete, burst len = 64 bytes */
593 	denali->host_write(denali, mode | 0x14000, 0x2400);
594 }
595 
596 static int denali_pio_read(struct denali_controller *denali, u32 *buf,
597 			   size_t size, int page)
598 {
599 	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
600 	u32 irq_status, ecc_err_mask;
601 	int i;
602 
603 	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
604 		ecc_err_mask = INTR__ECC_UNCOR_ERR;
605 	else
606 		ecc_err_mask = INTR__ECC_ERR;
607 
608 	denali_reset_irq(denali);
609 
610 	for (i = 0; i < size / 4; i++)
611 		buf[i] = denali->host_read(denali, addr);
612 
613 	irq_status = denali_wait_for_irq(denali, INTR__PAGE_XFER_INC);
614 	if (!(irq_status & INTR__PAGE_XFER_INC))
615 		return -EIO;
616 
617 	if (irq_status & INTR__ERASED_PAGE)
618 		memset(buf, 0xff, size);
619 
620 	return irq_status & ecc_err_mask ? -EBADMSG : 0;
621 }
622 
623 static int denali_pio_write(struct denali_controller *denali, const u32 *buf,
624 			    size_t size, int page)
625 {
626 	u32 addr = DENALI_MAP01 | DENALI_BANK(denali) | page;
627 	u32 irq_status;
628 	int i;
629 
630 	denali_reset_irq(denali);
631 
632 	for (i = 0; i < size / 4; i++)
633 		denali->host_write(denali, addr, buf[i]);
634 
635 	irq_status = denali_wait_for_irq(denali,
636 					 INTR__PROGRAM_COMP |
637 					 INTR__PROGRAM_FAIL);
638 	if (!(irq_status & INTR__PROGRAM_COMP))
639 		return -EIO;
640 
641 	return 0;
642 }
643 
644 static int denali_pio_xfer(struct denali_controller *denali, void *buf,
645 			   size_t size, int page, bool write)
646 {
647 	if (write)
648 		return denali_pio_write(denali, buf, size, page);
649 	else
650 		return denali_pio_read(denali, buf, size, page);
651 }
652 
653 static int denali_dma_xfer(struct denali_controller *denali, void *buf,
654 			   size_t size, int page, bool write)
655 {
656 	dma_addr_t dma_addr;
657 	u32 irq_mask, irq_status, ecc_err_mask;
658 	enum dma_data_direction dir = write ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
659 	int ret = 0;
660 
661 	dma_addr = dma_map_single(denali->dev, buf, size, dir);
662 	if (dma_mapping_error(denali->dev, dma_addr)) {
663 		dev_dbg(denali->dev, "Failed to DMA-map buffer. Trying PIO.\n");
664 		return denali_pio_xfer(denali, buf, size, page, write);
665 	}
666 
667 	if (write) {
668 		/*
669 		 * INTR__PROGRAM_COMP is never asserted for the DMA transfer.
670 		 * We can use INTR__DMA_CMD_COMP instead.  This flag is asserted
671 		 * when the page program is completed.
672 		 */
673 		irq_mask = INTR__DMA_CMD_COMP | INTR__PROGRAM_FAIL;
674 		ecc_err_mask = 0;
675 	} else if (denali->caps & DENALI_CAP_HW_ECC_FIXUP) {
676 		irq_mask = INTR__DMA_CMD_COMP;
677 		ecc_err_mask = INTR__ECC_UNCOR_ERR;
678 	} else {
679 		irq_mask = INTR__DMA_CMD_COMP;
680 		ecc_err_mask = INTR__ECC_ERR;
681 	}
682 
683 	iowrite32(DMA_ENABLE__FLAG, denali->reg + DMA_ENABLE);
684 	/*
685 	 * The ->setup_dma() hook kicks DMA by using the data/command
686 	 * interface, which belongs to a different AXI port from the
687 	 * register interface.  Read back the register to avoid a race.
688 	 */
689 	ioread32(denali->reg + DMA_ENABLE);
690 
691 	denali_reset_irq(denali);
692 	denali->setup_dma(denali, dma_addr, page, write);
693 
694 	irq_status = denali_wait_for_irq(denali, irq_mask);
695 	if (!(irq_status & INTR__DMA_CMD_COMP))
696 		ret = -EIO;
697 	else if (irq_status & ecc_err_mask)
698 		ret = -EBADMSG;
699 
700 	iowrite32(0, denali->reg + DMA_ENABLE);
701 
702 	dma_unmap_single(denali->dev, dma_addr, size, dir);
703 
704 	if (irq_status & INTR__ERASED_PAGE)
705 		memset(buf, 0xff, size);
706 
707 	return ret;
708 }
709 
710 static int denali_page_xfer(struct nand_chip *chip, void *buf, size_t size,
711 			    int page, bool write)
712 {
713 	struct denali_controller *denali = to_denali_controller(chip);
714 
715 	denali_select_target(chip, chip->cur_cs);
716 
717 	if (denali->dma_avail)
718 		return denali_dma_xfer(denali, buf, size, page, write);
719 	else
720 		return denali_pio_xfer(denali, buf, size, page, write);
721 }
722 
723 static int denali_read_page(struct nand_chip *chip, u8 *buf,
724 			    int oob_required, int page)
725 {
726 	struct denali_controller *denali = to_denali_controller(chip);
727 	struct mtd_info *mtd = nand_to_mtd(chip);
728 	unsigned long uncor_ecc_flags = 0;
729 	int stat = 0;
730 	int ret;
731 
732 	ret = denali_page_xfer(chip, buf, mtd->writesize, page, false);
733 	if (ret && ret != -EBADMSG)
734 		return ret;
735 
736 	if (denali->caps & DENALI_CAP_HW_ECC_FIXUP)
737 		stat = denali_hw_ecc_fixup(chip, &uncor_ecc_flags);
738 	else if (ret == -EBADMSG)
739 		stat = denali_sw_ecc_fixup(chip, &uncor_ecc_flags, buf);
740 
741 	if (stat < 0)
742 		return stat;
743 
744 	if (uncor_ecc_flags) {
745 		ret = denali_read_oob(chip, page);
746 		if (ret)
747 			return ret;
748 
749 		stat = denali_check_erased_page(chip, buf,
750 						uncor_ecc_flags, stat);
751 	}
752 
753 	return stat;
754 }
755 
756 static int denali_write_page(struct nand_chip *chip, const u8 *buf,
757 			     int oob_required, int page)
758 {
759 	struct mtd_info *mtd = nand_to_mtd(chip);
760 
761 	return denali_page_xfer(chip, (void *)buf, mtd->writesize, page, true);
762 }
763 
764 static int denali_setup_interface(struct nand_chip *chip, int chipnr,
765 				  const struct nand_interface_config *conf)
766 {
767 	static const unsigned int data_setup_on_host = 10000;
768 	struct denali_controller *denali = to_denali_controller(chip);
769 	struct denali_chip_sel *sel;
770 	const struct nand_sdr_timings *timings;
771 	unsigned long t_x, mult_x;
772 	int acc_clks, re_2_we, re_2_re, we_2_re, addr_2_data;
773 	int rdwr_en_lo, rdwr_en_hi, rdwr_en_lo_hi, cs_setup;
774 	int addr_2_data_mask;
775 	u32 tmp;
776 
777 	timings = nand_get_sdr_timings(conf);
778 	if (IS_ERR(timings))
779 		return PTR_ERR(timings);
780 
781 	/* clk_x period in picoseconds */
782 	t_x = DIV_ROUND_DOWN_ULL(1000000000000ULL, denali->clk_x_rate);
783 	if (!t_x)
784 		return -EINVAL;
785 
786 	/*
787 	 * The bus interface clock, clk_x, is phase aligned with the core clock.
788 	 * The clk_x is an integral multiple N of the core clk.  The value N is
789 	 * configured at IP delivery time, and its available value is 4, 5, 6.
790 	 */
791 	mult_x = DIV_ROUND_CLOSEST_ULL(denali->clk_x_rate, denali->clk_rate);
792 	if (mult_x < 4 || mult_x > 6)
793 		return -EINVAL;
794 
795 	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
796 		return 0;
797 
798 	sel = &to_denali_chip(chip)->sels[chipnr];
799 
800 	/* tRWH -> RE_2_WE */
801 	re_2_we = DIV_ROUND_UP(timings->tRHW_min, t_x);
802 	re_2_we = min_t(int, re_2_we, RE_2_WE__VALUE);
803 
804 	tmp = ioread32(denali->reg + RE_2_WE);
805 	tmp &= ~RE_2_WE__VALUE;
806 	tmp |= FIELD_PREP(RE_2_WE__VALUE, re_2_we);
807 	sel->re_2_we = tmp;
808 
809 	/* tRHZ -> RE_2_RE */
810 	re_2_re = DIV_ROUND_UP(timings->tRHZ_max, t_x);
811 	re_2_re = min_t(int, re_2_re, RE_2_RE__VALUE);
812 
813 	tmp = ioread32(denali->reg + RE_2_RE);
814 	tmp &= ~RE_2_RE__VALUE;
815 	tmp |= FIELD_PREP(RE_2_RE__VALUE, re_2_re);
816 	sel->re_2_re = tmp;
817 
818 	/*
819 	 * tCCS, tWHR -> WE_2_RE
820 	 *
821 	 * With WE_2_RE properly set, the Denali controller automatically takes
822 	 * care of the delay; the driver need not set NAND_WAIT_TCCS.
823 	 */
824 	we_2_re = DIV_ROUND_UP(max(timings->tCCS_min, timings->tWHR_min), t_x);
825 	we_2_re = min_t(int, we_2_re, TWHR2_AND_WE_2_RE__WE_2_RE);
826 
827 	tmp = ioread32(denali->reg + TWHR2_AND_WE_2_RE);
828 	tmp &= ~TWHR2_AND_WE_2_RE__WE_2_RE;
829 	tmp |= FIELD_PREP(TWHR2_AND_WE_2_RE__WE_2_RE, we_2_re);
830 	sel->hwhr2_and_we_2_re = tmp;
831 
832 	/* tADL -> ADDR_2_DATA */
833 
834 	/* for older versions, ADDR_2_DATA is only 6 bit wide */
835 	addr_2_data_mask = TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
836 	if (denali->revision < 0x0501)
837 		addr_2_data_mask >>= 1;
838 
839 	addr_2_data = DIV_ROUND_UP(timings->tADL_min, t_x);
840 	addr_2_data = min_t(int, addr_2_data, addr_2_data_mask);
841 
842 	tmp = ioread32(denali->reg + TCWAW_AND_ADDR_2_DATA);
843 	tmp &= ~TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA;
844 	tmp |= FIELD_PREP(TCWAW_AND_ADDR_2_DATA__ADDR_2_DATA, addr_2_data);
845 	sel->tcwaw_and_addr_2_data = tmp;
846 
847 	/* tREH, tWH -> RDWR_EN_HI_CNT */
848 	rdwr_en_hi = DIV_ROUND_UP(max(timings->tREH_min, timings->tWH_min),
849 				  t_x);
850 	rdwr_en_hi = min_t(int, rdwr_en_hi, RDWR_EN_HI_CNT__VALUE);
851 
852 	tmp = ioread32(denali->reg + RDWR_EN_HI_CNT);
853 	tmp &= ~RDWR_EN_HI_CNT__VALUE;
854 	tmp |= FIELD_PREP(RDWR_EN_HI_CNT__VALUE, rdwr_en_hi);
855 	sel->rdwr_en_hi_cnt = tmp;
856 
857 	/*
858 	 * tREA -> ACC_CLKS
859 	 * tRP, tWP, tRHOH, tRC, tWC -> RDWR_EN_LO_CNT
860 	 */
861 
862 	/*
863 	 * Determine the minimum of acc_clks to meet the setup timing when
864 	 * capturing the incoming data.
865 	 *
866 	 * The delay on the chip side is well-defined as tREA, but we need to
867 	 * take additional delay into account. This includes a certain degree
868 	 * of unknowledge, such as signal propagation delays on the PCB and
869 	 * in the SoC, load capacity of the I/O pins, etc.
870 	 */
871 	acc_clks = DIV_ROUND_UP(timings->tREA_max + data_setup_on_host, t_x);
872 
873 	/* Determine the minimum of rdwr_en_lo_cnt from RE#/WE# pulse width */
874 	rdwr_en_lo = DIV_ROUND_UP(max(timings->tRP_min, timings->tWP_min), t_x);
875 
876 	/* Extend rdwr_en_lo to meet the data hold timing */
877 	rdwr_en_lo = max_t(int, rdwr_en_lo,
878 			   acc_clks - timings->tRHOH_min / t_x);
879 
880 	/* Extend rdwr_en_lo to meet the requirement for RE#/WE# cycle time */
881 	rdwr_en_lo_hi = DIV_ROUND_UP(max(timings->tRC_min, timings->tWC_min),
882 				     t_x);
883 	rdwr_en_lo = max(rdwr_en_lo, rdwr_en_lo_hi - rdwr_en_hi);
884 	rdwr_en_lo = min_t(int, rdwr_en_lo, RDWR_EN_LO_CNT__VALUE);
885 
886 	/* Center the data latch timing for extra safety */
887 	acc_clks = (acc_clks + rdwr_en_lo +
888 		    DIV_ROUND_UP(timings->tRHOH_min, t_x)) / 2;
889 	acc_clks = min_t(int, acc_clks, ACC_CLKS__VALUE);
890 
891 	tmp = ioread32(denali->reg + ACC_CLKS);
892 	tmp &= ~ACC_CLKS__VALUE;
893 	tmp |= FIELD_PREP(ACC_CLKS__VALUE, acc_clks);
894 	sel->acc_clks = tmp;
895 
896 	tmp = ioread32(denali->reg + RDWR_EN_LO_CNT);
897 	tmp &= ~RDWR_EN_LO_CNT__VALUE;
898 	tmp |= FIELD_PREP(RDWR_EN_LO_CNT__VALUE, rdwr_en_lo);
899 	sel->rdwr_en_lo_cnt = tmp;
900 
901 	/* tCS, tCEA -> CS_SETUP_CNT */
902 	cs_setup = max3((int)DIV_ROUND_UP(timings->tCS_min, t_x) - rdwr_en_lo,
903 			(int)DIV_ROUND_UP(timings->tCEA_max, t_x) - acc_clks,
904 			0);
905 	cs_setup = min_t(int, cs_setup, CS_SETUP_CNT__VALUE);
906 
907 	tmp = ioread32(denali->reg + CS_SETUP_CNT);
908 	tmp &= ~CS_SETUP_CNT__VALUE;
909 	tmp |= FIELD_PREP(CS_SETUP_CNT__VALUE, cs_setup);
910 	sel->cs_setup_cnt = tmp;
911 
912 	return 0;
913 }
914 
915 int denali_calc_ecc_bytes(int step_size, int strength)
916 {
917 	/* BCH code.  Denali requires ecc.bytes to be multiple of 2 */
918 	return DIV_ROUND_UP(strength * fls(step_size * 8), 16) * 2;
919 }
920 EXPORT_SYMBOL(denali_calc_ecc_bytes);
921 
922 static int denali_ooblayout_ecc(struct mtd_info *mtd, int section,
923 				struct mtd_oob_region *oobregion)
924 {
925 	struct nand_chip *chip = mtd_to_nand(mtd);
926 	struct denali_controller *denali = to_denali_controller(chip);
927 
928 	if (section > 0)
929 		return -ERANGE;
930 
931 	oobregion->offset = denali->oob_skip_bytes;
932 	oobregion->length = chip->ecc.total;
933 
934 	return 0;
935 }
936 
937 static int denali_ooblayout_free(struct mtd_info *mtd, int section,
938 				 struct mtd_oob_region *oobregion)
939 {
940 	struct nand_chip *chip = mtd_to_nand(mtd);
941 	struct denali_controller *denali = to_denali_controller(chip);
942 
943 	if (section > 0)
944 		return -ERANGE;
945 
946 	oobregion->offset = chip->ecc.total + denali->oob_skip_bytes;
947 	oobregion->length = mtd->oobsize - oobregion->offset;
948 
949 	return 0;
950 }
951 
952 static const struct mtd_ooblayout_ops denali_ooblayout_ops = {
953 	.ecc = denali_ooblayout_ecc,
954 	.free = denali_ooblayout_free,
955 };
956 
957 static int denali_multidev_fixup(struct nand_chip *chip)
958 {
959 	struct denali_controller *denali = to_denali_controller(chip);
960 	struct mtd_info *mtd = nand_to_mtd(chip);
961 	struct nand_memory_organization *memorg;
962 
963 	memorg = nanddev_get_memorg(&chip->base);
964 
965 	/*
966 	 * Support for multi device:
967 	 * When the IP configuration is x16 capable and two x8 chips are
968 	 * connected in parallel, DEVICES_CONNECTED should be set to 2.
969 	 * In this case, the core framework knows nothing about this fact,
970 	 * so we should tell it the _logical_ pagesize and anything necessary.
971 	 */
972 	denali->devs_per_cs = ioread32(denali->reg + DEVICES_CONNECTED);
973 
974 	/*
975 	 * On some SoCs, DEVICES_CONNECTED is not auto-detected.
976 	 * For those, DEVICES_CONNECTED is left to 0.  Set 1 if it is the case.
977 	 */
978 	if (denali->devs_per_cs == 0) {
979 		denali->devs_per_cs = 1;
980 		iowrite32(1, denali->reg + DEVICES_CONNECTED);
981 	}
982 
983 	if (denali->devs_per_cs == 1)
984 		return 0;
985 
986 	if (denali->devs_per_cs != 2) {
987 		dev_err(denali->dev, "unsupported number of devices %d\n",
988 			denali->devs_per_cs);
989 		return -EINVAL;
990 	}
991 
992 	/* 2 chips in parallel */
993 	memorg->pagesize <<= 1;
994 	memorg->oobsize <<= 1;
995 	mtd->size <<= 1;
996 	mtd->erasesize <<= 1;
997 	mtd->writesize <<= 1;
998 	mtd->oobsize <<= 1;
999 	chip->page_shift += 1;
1000 	chip->phys_erase_shift += 1;
1001 	chip->bbt_erase_shift += 1;
1002 	chip->chip_shift += 1;
1003 	chip->pagemask <<= 1;
1004 	chip->ecc.size <<= 1;
1005 	chip->ecc.bytes <<= 1;
1006 	chip->ecc.strength <<= 1;
1007 	denali->oob_skip_bytes <<= 1;
1008 
1009 	return 0;
1010 }
1011 
1012 static int denali_attach_chip(struct nand_chip *chip)
1013 {
1014 	struct denali_controller *denali = to_denali_controller(chip);
1015 	struct mtd_info *mtd = nand_to_mtd(chip);
1016 	int ret;
1017 
1018 	ret = nand_ecc_choose_conf(chip, denali->ecc_caps,
1019 				   mtd->oobsize - denali->oob_skip_bytes);
1020 	if (ret) {
1021 		dev_err(denali->dev, "Failed to setup ECC settings.\n");
1022 		return ret;
1023 	}
1024 
1025 	dev_dbg(denali->dev,
1026 		"chosen ECC settings: step=%d, strength=%d, bytes=%d\n",
1027 		chip->ecc.size, chip->ecc.strength, chip->ecc.bytes);
1028 
1029 	ret = denali_multidev_fixup(chip);
1030 	if (ret)
1031 		return ret;
1032 
1033 	return 0;
1034 }
1035 
1036 static void denali_exec_in8(struct denali_controller *denali, u32 type,
1037 			    u8 *buf, unsigned int len)
1038 {
1039 	int i;
1040 
1041 	for (i = 0; i < len; i++)
1042 		buf[i] = denali->host_read(denali, type | DENALI_BANK(denali));
1043 }
1044 
1045 static void denali_exec_in16(struct denali_controller *denali, u32 type,
1046 			     u8 *buf, unsigned int len)
1047 {
1048 	u32 data;
1049 	int i;
1050 
1051 	for (i = 0; i < len; i += 2) {
1052 		data = denali->host_read(denali, type | DENALI_BANK(denali));
1053 		/* bit 31:24 and 15:8 are used for DDR */
1054 		buf[i] = data;
1055 		buf[i + 1] = data >> 16;
1056 	}
1057 }
1058 
1059 static void denali_exec_in(struct denali_controller *denali, u32 type,
1060 			   u8 *buf, unsigned int len, bool width16)
1061 {
1062 	if (width16)
1063 		denali_exec_in16(denali, type, buf, len);
1064 	else
1065 		denali_exec_in8(denali, type, buf, len);
1066 }
1067 
1068 static void denali_exec_out8(struct denali_controller *denali, u32 type,
1069 			     const u8 *buf, unsigned int len)
1070 {
1071 	int i;
1072 
1073 	for (i = 0; i < len; i++)
1074 		denali->host_write(denali, type | DENALI_BANK(denali), buf[i]);
1075 }
1076 
1077 static void denali_exec_out16(struct denali_controller *denali, u32 type,
1078 			      const u8 *buf, unsigned int len)
1079 {
1080 	int i;
1081 
1082 	for (i = 0; i < len; i += 2)
1083 		denali->host_write(denali, type | DENALI_BANK(denali),
1084 				   buf[i + 1] << 16 | buf[i]);
1085 }
1086 
1087 static void denali_exec_out(struct denali_controller *denali, u32 type,
1088 			    const u8 *buf, unsigned int len, bool width16)
1089 {
1090 	if (width16)
1091 		denali_exec_out16(denali, type, buf, len);
1092 	else
1093 		denali_exec_out8(denali, type, buf, len);
1094 }
1095 
1096 static int denali_exec_waitrdy(struct denali_controller *denali)
1097 {
1098 	u32 irq_stat;
1099 
1100 	/* R/B# pin transitioned from low to high? */
1101 	irq_stat = denali_wait_for_irq(denali, INTR__INT_ACT);
1102 
1103 	/* Just in case nand_operation has multiple NAND_OP_WAITRDY_INSTR. */
1104 	denali_reset_irq(denali);
1105 
1106 	return irq_stat & INTR__INT_ACT ? 0 : -EIO;
1107 }
1108 
1109 static int denali_exec_instr(struct nand_chip *chip,
1110 			     const struct nand_op_instr *instr)
1111 {
1112 	struct denali_controller *denali = to_denali_controller(chip);
1113 
1114 	switch (instr->type) {
1115 	case NAND_OP_CMD_INSTR:
1116 		denali_exec_out8(denali, DENALI_MAP11_CMD,
1117 				 &instr->ctx.cmd.opcode, 1);
1118 		return 0;
1119 	case NAND_OP_ADDR_INSTR:
1120 		denali_exec_out8(denali, DENALI_MAP11_ADDR,
1121 				 instr->ctx.addr.addrs,
1122 				 instr->ctx.addr.naddrs);
1123 		return 0;
1124 	case NAND_OP_DATA_IN_INSTR:
1125 		denali_exec_in(denali, DENALI_MAP11_DATA,
1126 			       instr->ctx.data.buf.in,
1127 			       instr->ctx.data.len,
1128 			       !instr->ctx.data.force_8bit &&
1129 			       chip->options & NAND_BUSWIDTH_16);
1130 		return 0;
1131 	case NAND_OP_DATA_OUT_INSTR:
1132 		denali_exec_out(denali, DENALI_MAP11_DATA,
1133 				instr->ctx.data.buf.out,
1134 				instr->ctx.data.len,
1135 				!instr->ctx.data.force_8bit &&
1136 				chip->options & NAND_BUSWIDTH_16);
1137 		return 0;
1138 	case NAND_OP_WAITRDY_INSTR:
1139 		return denali_exec_waitrdy(denali);
1140 	default:
1141 		WARN_ONCE(1, "unsupported NAND instruction type: %d\n",
1142 			  instr->type);
1143 
1144 		return -EINVAL;
1145 	}
1146 }
1147 
1148 static int denali_exec_op(struct nand_chip *chip,
1149 			  const struct nand_operation *op, bool check_only)
1150 {
1151 	int i, ret;
1152 
1153 	if (check_only)
1154 		return 0;
1155 
1156 	denali_select_target(chip, op->cs);
1157 
1158 	/*
1159 	 * Some commands contain NAND_OP_WAITRDY_INSTR.
1160 	 * irq must be cleared here to catch the R/B# interrupt there.
1161 	 */
1162 	denali_reset_irq(to_denali_controller(chip));
1163 
1164 	for (i = 0; i < op->ninstrs; i++) {
1165 		ret = denali_exec_instr(chip, &op->instrs[i]);
1166 		if (ret)
1167 			return ret;
1168 	}
1169 
1170 	return 0;
1171 }
1172 
1173 static const struct nand_controller_ops denali_controller_ops = {
1174 	.attach_chip = denali_attach_chip,
1175 	.exec_op = denali_exec_op,
1176 	.setup_interface = denali_setup_interface,
1177 };
1178 
1179 int denali_chip_init(struct denali_controller *denali,
1180 		     struct denali_chip *dchip)
1181 {
1182 	struct nand_chip *chip = &dchip->chip;
1183 	struct mtd_info *mtd = nand_to_mtd(chip);
1184 	struct denali_chip *dchip2;
1185 	int i, j, ret;
1186 
1187 	chip->controller = &denali->controller;
1188 
1189 	/* sanity checks for bank numbers */
1190 	for (i = 0; i < dchip->nsels; i++) {
1191 		unsigned int bank = dchip->sels[i].bank;
1192 
1193 		if (bank >= denali->nbanks) {
1194 			dev_err(denali->dev, "unsupported bank %d\n", bank);
1195 			return -EINVAL;
1196 		}
1197 
1198 		for (j = 0; j < i; j++) {
1199 			if (bank == dchip->sels[j].bank) {
1200 				dev_err(denali->dev,
1201 					"bank %d is assigned twice in the same chip\n",
1202 					bank);
1203 				return -EINVAL;
1204 			}
1205 		}
1206 
1207 		list_for_each_entry(dchip2, &denali->chips, node) {
1208 			for (j = 0; j < dchip2->nsels; j++) {
1209 				if (bank == dchip2->sels[j].bank) {
1210 					dev_err(denali->dev,
1211 						"bank %d is already used\n",
1212 						bank);
1213 					return -EINVAL;
1214 				}
1215 			}
1216 		}
1217 	}
1218 
1219 	mtd->dev.parent = denali->dev;
1220 
1221 	/*
1222 	 * Fallback to the default name if DT did not give "label" property.
1223 	 * Use "label" property if multiple chips are connected.
1224 	 */
1225 	if (!mtd->name && list_empty(&denali->chips))
1226 		mtd->name = "denali-nand";
1227 
1228 	if (denali->dma_avail) {
1229 		chip->options |= NAND_USES_DMA;
1230 		chip->buf_align = 16;
1231 	}
1232 
1233 	/* clk rate info is needed for setup_interface */
1234 	if (!denali->clk_rate || !denali->clk_x_rate)
1235 		chip->options |= NAND_KEEP_TIMINGS;
1236 
1237 	chip->bbt_options |= NAND_BBT_USE_FLASH;
1238 	chip->bbt_options |= NAND_BBT_NO_OOB;
1239 	chip->options |= NAND_NO_SUBPAGE_WRITE;
1240 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
1241 	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
1242 	chip->ecc.read_page = denali_read_page;
1243 	chip->ecc.write_page = denali_write_page;
1244 	chip->ecc.read_page_raw = denali_read_page_raw;
1245 	chip->ecc.write_page_raw = denali_write_page_raw;
1246 	chip->ecc.read_oob = denali_read_oob;
1247 	chip->ecc.write_oob = denali_write_oob;
1248 
1249 	mtd_set_ooblayout(mtd, &denali_ooblayout_ops);
1250 
1251 	ret = nand_scan(chip, dchip->nsels);
1252 	if (ret)
1253 		return ret;
1254 
1255 	ret = mtd_device_register(mtd, NULL, 0);
1256 	if (ret) {
1257 		dev_err(denali->dev, "Failed to register MTD: %d\n", ret);
1258 		goto cleanup_nand;
1259 	}
1260 
1261 	list_add_tail(&dchip->node, &denali->chips);
1262 
1263 	return 0;
1264 
1265 cleanup_nand:
1266 	nand_cleanup(chip);
1267 
1268 	return ret;
1269 }
1270 EXPORT_SYMBOL_GPL(denali_chip_init);
1271 
1272 int denali_init(struct denali_controller *denali)
1273 {
1274 	u32 features = ioread32(denali->reg + FEATURES);
1275 	int ret;
1276 
1277 	nand_controller_init(&denali->controller);
1278 	denali->controller.ops = &denali_controller_ops;
1279 	init_completion(&denali->complete);
1280 	spin_lock_init(&denali->irq_lock);
1281 	INIT_LIST_HEAD(&denali->chips);
1282 	denali->active_bank = DENALI_INVALID_BANK;
1283 
1284 	/*
1285 	 * The REVISION register may not be reliable. Platforms are allowed to
1286 	 * override it.
1287 	 */
1288 	if (!denali->revision)
1289 		denali->revision = swab16(ioread32(denali->reg + REVISION));
1290 
1291 	denali->nbanks = 1 << FIELD_GET(FEATURES__N_BANKS, features);
1292 
1293 	/* the encoding changed from rev 5.0 to 5.1 */
1294 	if (denali->revision < 0x0501)
1295 		denali->nbanks <<= 1;
1296 
1297 	if (features & FEATURES__DMA)
1298 		denali->dma_avail = true;
1299 
1300 	if (denali->dma_avail) {
1301 		int dma_bit = denali->caps & DENALI_CAP_DMA_64BIT ? 64 : 32;
1302 
1303 		ret = dma_set_mask(denali->dev, DMA_BIT_MASK(dma_bit));
1304 		if (ret) {
1305 			dev_info(denali->dev,
1306 				 "Failed to set DMA mask. Disabling DMA.\n");
1307 			denali->dma_avail = false;
1308 		}
1309 	}
1310 
1311 	if (denali->dma_avail) {
1312 		if (denali->caps & DENALI_CAP_DMA_64BIT)
1313 			denali->setup_dma = denali_setup_dma64;
1314 		else
1315 			denali->setup_dma = denali_setup_dma32;
1316 	}
1317 
1318 	if (features & FEATURES__INDEX_ADDR) {
1319 		denali->host_read = denali_indexed_read;
1320 		denali->host_write = denali_indexed_write;
1321 	} else {
1322 		denali->host_read = denali_direct_read;
1323 		denali->host_write = denali_direct_write;
1324 	}
1325 
1326 	/*
1327 	 * Set how many bytes should be skipped before writing data in OOB.
1328 	 * If a platform requests a non-zero value, set it to the register.
1329 	 * Otherwise, read the value out, expecting it has already been set up
1330 	 * by firmware.
1331 	 */
1332 	if (denali->oob_skip_bytes)
1333 		iowrite32(denali->oob_skip_bytes,
1334 			  denali->reg + SPARE_AREA_SKIP_BYTES);
1335 	else
1336 		denali->oob_skip_bytes = ioread32(denali->reg +
1337 						  SPARE_AREA_SKIP_BYTES);
1338 
1339 	iowrite32(0, denali->reg + TRANSFER_SPARE_REG);
1340 	iowrite32(GENMASK(denali->nbanks - 1, 0), denali->reg + RB_PIN_ENABLED);
1341 	iowrite32(CHIP_EN_DONT_CARE__FLAG, denali->reg + CHIP_ENABLE_DONT_CARE);
1342 	iowrite32(ECC_ENABLE__FLAG, denali->reg + ECC_ENABLE);
1343 	iowrite32(0xffff, denali->reg + SPARE_AREA_MARKER);
1344 	iowrite32(WRITE_PROTECT__FLAG, denali->reg + WRITE_PROTECT);
1345 
1346 	denali_clear_irq_all(denali);
1347 
1348 	ret = devm_request_irq(denali->dev, denali->irq, denali_isr,
1349 			       IRQF_SHARED, DENALI_NAND_NAME, denali);
1350 	if (ret) {
1351 		dev_err(denali->dev, "Unable to request IRQ\n");
1352 		return ret;
1353 	}
1354 
1355 	denali_enable_irq(denali);
1356 
1357 	return 0;
1358 }
1359 EXPORT_SYMBOL(denali_init);
1360 
1361 void denali_remove(struct denali_controller *denali)
1362 {
1363 	struct denali_chip *dchip, *tmp;
1364 	struct nand_chip *chip;
1365 	int ret;
1366 
1367 	list_for_each_entry_safe(dchip, tmp, &denali->chips, node) {
1368 		chip = &dchip->chip;
1369 		ret = mtd_device_unregister(nand_to_mtd(chip));
1370 		WARN_ON(ret);
1371 		nand_cleanup(chip);
1372 		list_del(&dchip->node);
1373 	}
1374 
1375 	denali_disable_irq(denali);
1376 }
1377 EXPORT_SYMBOL(denali_remove);
1378 
1379 MODULE_DESCRIPTION("Driver core for Denali NAND controller");
1380 MODULE_AUTHOR("Intel Corporation and its suppliers");
1381 MODULE_LICENSE("GPL v2");
1382