xref: /netbsd-src/sys/dev/nand/nand.c (revision 970906a863d300df9407fee4291473cb1e627bab)
1 /*	$NetBSD: nand.c,v 1.24 2016/10/04 14:43:55 kiyohara Exp $	*/
2 
3 /*-
4  * Copyright (c) 2010 Department of Software Engineering,
5  *		      University of Szeged, Hungary
6  * Copyright (c) 2010 Adam Hoka <ahoka@NetBSD.org>
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by the Department of Software Engineering, University of Szeged, Hungary
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 /* Common driver for NAND chips implementing the ONFI 2.2 specification */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: nand.c,v 1.24 2016/10/04 14:43:55 kiyohara Exp $");
38 
39 #include "locators.h"
40 
41 #include <sys/param.h>
42 #include <sys/types.h>
43 #include <sys/device.h>
44 #include <sys/kmem.h>
45 #include <sys/atomic.h>
46 
47 #include <dev/flash/flash.h>
48 #include <dev/flash/flash_io.h>
49 #include <dev/nand/nand.h>
50 #include <dev/nand/onfi.h>
51 #include <dev/nand/hamming.h>
52 #include <dev/nand/nand_bbt.h>
53 #include <dev/nand/nand_crc.h>
54 
55 #include "opt_nand.h"
56 
57 int nand_match(device_t, cfdata_t, void *);
58 void nand_attach(device_t, device_t, void *);
59 int nand_detach(device_t, int);
60 bool nand_shutdown(device_t, int);
61 
62 int nand_print(void *, const char *);
63 
64 static int nand_search(device_t, cfdata_t, const int *, void *);
65 static void nand_address_row(device_t, size_t);
66 static inline uint8_t nand_get_status(device_t);
67 static void nand_address_column(device_t, size_t, size_t);
68 static int nand_fill_chip_structure(device_t, struct nand_chip *);
69 static int nand_scan_media(device_t, struct nand_chip *);
70 static bool nand_check_wp(device_t);
71 
72 CFATTACH_DECL_NEW(nand, sizeof(struct nand_softc),
73     nand_match, nand_attach, nand_detach, NULL);
74 
75 #ifdef NAND_DEBUG
76 int	nanddebug = NAND_DEBUG;
77 #endif
78 
79 struct flash_interface nand_flash_if = {
80 	.type = FLASH_TYPE_NAND,
81 
82 	.read = nand_flash_read,
83 	.write = nand_flash_write,
84 	.erase = nand_flash_erase,
85 	.block_isbad = nand_flash_isbad,
86 	.block_markbad = nand_flash_markbad,
87 
88 	.submit = nand_flash_submit
89 };
90 
91 #ifdef NAND_VERBOSE
92 const struct nand_manufacturer nand_mfrs[] = {
93 	{ NAND_MFR_AMD,		"AMD" },
94 	{ NAND_MFR_FUJITSU,	"Fujitsu" },
95 	{ NAND_MFR_RENESAS,	"Renesas" },
96 	{ NAND_MFR_STMICRO,	"ST Micro" },
97 	{ NAND_MFR_MICRON,	"Micron" },
98 	{ NAND_MFR_NATIONAL,	"National" },
99 	{ NAND_MFR_TOSHIBA,	"Toshiba" },
100 	{ NAND_MFR_HYNIX,	"Hynix" },
101 	{ NAND_MFR_SAMSUNG,	"Samsung" },
102 	{ NAND_MFR_UNKNOWN,	"Unknown" }
103 };
104 
105 static const char *
106 nand_midtoname(int id)
107 {
108 	int i;
109 
110 	for (i = 0; nand_mfrs[i].id != 0; i++) {
111 		if (nand_mfrs[i].id == id)
112 			return nand_mfrs[i].name;
113 	}
114 
115 	KASSERT(nand_mfrs[i].id == 0);
116 
117 	return nand_mfrs[i].name;
118 }
119 #endif
120 
121 /* ARGSUSED */
122 int
123 nand_match(device_t parent, cfdata_t match, void *aux)
124 {
125 	/* pseudo device, always attaches */
126 	return 1;
127 }
128 
129 void
130 nand_attach(device_t parent, device_t self, void *aux)
131 {
132 	struct nand_softc *sc = device_private(self);
133 	struct nand_attach_args *naa = aux;
134 	struct nand_chip *chip = &sc->sc_chip;
135 
136 	sc->sc_dev = self;
137 	sc->controller_dev = parent;
138 	sc->nand_if = naa->naa_nand_if;
139 
140 	aprint_naive("\n");
141 
142 	if (nand_check_wp(self)) {
143 		aprint_error("NAND chip is write protected!\n");
144 		return;
145 	}
146 
147 	if (nand_scan_media(self, chip)) {
148 		return;
149 	}
150 
151 	nand_flash_if.erasesize = chip->nc_block_size;
152 	nand_flash_if.page_size = chip->nc_page_size;
153 	nand_flash_if.writesize = chip->nc_page_size;
154 
155 	/* allocate cache */
156 	chip->nc_oob_cache = kmem_alloc(chip->nc_spare_size, KM_SLEEP);
157 	chip->nc_page_cache = kmem_alloc(chip->nc_page_size, KM_SLEEP);
158 
159 	mutex_init(&sc->sc_device_lock, MUTEX_DEFAULT, IPL_NONE);
160 
161 	if (flash_sync_thread_init(&sc->sc_flash_io, self, &nand_flash_if)) {
162 		goto error;
163 	}
164 
165 	if (!pmf_device_register1(sc->sc_dev, NULL, NULL, nand_shutdown))
166 		aprint_error_dev(sc->sc_dev,
167 		    "couldn't establish power handler\n");
168 
169 #ifdef NAND_BBT
170 	nand_bbt_init(self);
171 	nand_bbt_scan(self);
172 #endif
173 
174 	/*
175 	 * Attach all our devices
176 	 */
177 	config_search_ia(nand_search, self, NULL, NULL);
178 
179 	return;
180 error:
181 	kmem_free(chip->nc_oob_cache, chip->nc_spare_size);
182 	kmem_free(chip->nc_page_cache, chip->nc_page_size);
183 	mutex_destroy(&sc->sc_device_lock);
184 }
185 
186 static int
187 nand_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux)
188 {
189 	struct nand_softc *sc = device_private(parent);
190 	struct nand_chip *chip = &sc->sc_chip;
191 	struct flash_attach_args faa;
192 
193 	faa.flash_if = &nand_flash_if;
194 
195 	faa.partinfo.part_offset = cf->cf_loc[FLASHBUSCF_OFFSET];
196 
197 	if (cf->cf_loc[FLASHBUSCF_SIZE] == 0) {
198 		faa.partinfo.part_size = chip->nc_size -
199 		    faa.partinfo.part_offset;
200 	} else {
201 		faa.partinfo.part_size = cf->cf_loc[FLASHBUSCF_SIZE];
202 	}
203 
204 	if (cf->cf_loc[FLASHBUSCF_READONLY])
205 		faa.partinfo.part_flags = FLASH_PART_READONLY;
206 	else
207 		faa.partinfo.part_flags = 0;
208 
209 	if (config_match(parent, cf, &faa)) {
210 		if (config_attach(parent, cf, &faa, nand_print) != NULL) {
211 			return 0;
212 		} else {
213 			return 1;
214 		}
215 	}
216 
217 	return 1;
218 }
219 
220 int
221 nand_detach(device_t self, int flags)
222 {
223 	struct nand_softc *sc = device_private(self);
224 	struct nand_chip *chip = &sc->sc_chip;
225 	int error = 0;
226 
227 	error = config_detach_children(self, flags);
228 	if (error) {
229 		return error;
230 	}
231 
232 	flash_sync_thread_destroy(&sc->sc_flash_io);
233 #ifdef NAND_BBT
234 	nand_bbt_detach(self);
235 #endif
236 	/* free oob cache */
237 	kmem_free(chip->nc_oob_cache, chip->nc_spare_size);
238 	kmem_free(chip->nc_page_cache, chip->nc_page_size);
239 	kmem_free(chip->nc_ecc_cache, chip->nc_ecc->necc_size);
240 
241 	mutex_destroy(&sc->sc_device_lock);
242 
243 	pmf_device_deregister(sc->sc_dev);
244 
245 	return error;
246 }
247 
248 int
249 nand_print(void *aux, const char *pnp)
250 {
251 	if (pnp != NULL)
252 		aprint_normal("nand at %s\n", pnp);
253 
254 	return UNCONF;
255 }
256 
257 /* ask for a nand driver to attach to the controller */
258 device_t
259 nand_attach_mi(struct nand_interface *nand_if, device_t parent)
260 {
261 	struct nand_attach_args arg;
262 
263 	KASSERT(nand_if != NULL);
264 
265 	/* fill the defaults if we have null pointers */
266 	if (nand_if->program_page == NULL) {
267 		nand_if->program_page = &nand_default_program_page;
268 	}
269 
270 	if (nand_if->read_page == NULL) {
271 		nand_if->read_page = &nand_default_read_page;
272 	}
273 
274 	arg.naa_nand_if = nand_if;
275 	return config_found_ia(parent, "nandbus", &arg, nand_print);
276 }
277 
278 /* default everything to reasonable values, to ease future api changes */
279 void
280 nand_init_interface(struct nand_interface *interface)
281 {
282 	interface->select = &nand_default_select;
283 	interface->command = NULL;
284 	interface->address = NULL;
285 	interface->read_buf_1 = NULL;
286 	interface->read_buf_2 = NULL;
287 	interface->read_1 = NULL;
288 	interface->read_2 = NULL;
289 	interface->write_buf_1 = NULL;
290 	interface->write_buf_2 = NULL;
291 	interface->write_1 = NULL;
292 	interface->write_2 = NULL;
293 	interface->busy = NULL;
294 
295 	/*-
296 	 * most drivers dont want to change this, but some implement
297 	 * read/program in one step
298 	 */
299 	interface->program_page = &nand_default_program_page;
300 	interface->read_page = &nand_default_read_page;
301 
302 	/* default to soft ecc, that should work everywhere */
303 	interface->ecc_compute = &nand_default_ecc_compute;
304 	interface->ecc_correct = &nand_default_ecc_correct;
305 	interface->ecc_prepare = NULL;
306 	interface->ecc.necc_code_size = 3;
307 	interface->ecc.necc_block_size = 256;
308 	interface->ecc.necc_type = NAND_ECC_TYPE_SW;
309 }
310 
311 #if 0
312 /* handle quirks here */
313 static void
314 nand_quirks(device_t self, struct nand_chip *chip)
315 {
316 	/* this is an example only! */
317 	switch (chip->nc_manf_id) {
318 	case NAND_MFR_SAMSUNG:
319 		if (chip->nc_dev_id == 0x00) {
320 			/* do something only samsung chips need */
321 			/* or */
322 			/* chip->nc_quirks |= NC_QUIRK_NO_READ_START */
323 		}
324 	}
325 
326 	return;
327 }
328 #endif
329 
330 static int
331 nand_fill_chip_structure_legacy(device_t self, struct nand_chip *chip)
332 {
333 	switch (chip->nc_manf_id) {
334 	case NAND_MFR_MICRON:
335 		return nand_read_parameters_micron(self, chip);
336 	case NAND_MFR_SAMSUNG:
337 		return nand_read_parameters_samsung(self, chip);
338 	default:
339 		return 1;
340 	}
341 
342 	return 0;
343 }
344 
345 /**
346  * scan media to determine the chip's properties
347  * this function resets the device
348  */
349 static int
350 nand_scan_media(device_t self, struct nand_chip *chip)
351 {
352 	struct nand_softc *sc = device_private(self);
353 	struct nand_ecc *ecc;
354 	uint8_t onfi_signature[4];
355 
356 	nand_select(self, true);
357 	nand_command(self, ONFI_RESET);
358 	KASSERT(nand_get_status(self) & ONFI_STATUS_RDY);
359 	nand_select(self, false);
360 
361 	/* check if the device implements the ONFI standard */
362 	nand_select(self, true);
363 	nand_command(self, ONFI_READ_ID);
364 	nand_address(self, 0x20);
365 	nand_read_1(self, &onfi_signature[0]);
366 	nand_read_1(self, &onfi_signature[1]);
367 	nand_read_1(self, &onfi_signature[2]);
368 	nand_read_1(self, &onfi_signature[3]);
369 	nand_select(self, false);
370 
371 	if (onfi_signature[0] != 'O' || onfi_signature[1] != 'N' ||
372 	    onfi_signature[2] != 'F' || onfi_signature[3] != 'I') {
373 		chip->nc_isonfi = false;
374 
375 		aprint_normal(": Legacy NAND Flash\n");
376 
377 		nand_read_id(self, &chip->nc_manf_id, &chip->nc_dev_id);
378 
379 		if (nand_fill_chip_structure_legacy(self, chip)) {
380 			aprint_error_dev(self,
381 			    "can't read device parameters for legacy chip\n");
382 			return 1;
383 		}
384 	} else {
385 		chip->nc_isonfi = true;
386 
387 		aprint_normal(": ONFI NAND Flash\n");
388 
389 		nand_read_id(self, &chip->nc_manf_id, &chip->nc_dev_id);
390 
391 		if (nand_fill_chip_structure(self, chip)) {
392 			aprint_error_dev(self,
393 			    "can't read device parameters\n");
394 			return 1;
395 		}
396 	}
397 
398 #ifdef NAND_VERBOSE
399 	aprint_normal_dev(self,
400 	    "manufacturer id: 0x%.2x (%s), device id: 0x%.2x\n",
401 	    chip->nc_manf_id,
402 	    nand_midtoname(chip->nc_manf_id),
403 	    chip->nc_dev_id);
404 #endif
405 
406 	aprint_normal_dev(self,
407 	    "page size: %" PRIu32 " bytes, spare size: %" PRIu32 " bytes, "
408 	    "block size: %" PRIu32 " bytes\n",
409 	    chip->nc_page_size, chip->nc_spare_size, chip->nc_block_size);
410 
411 	aprint_normal_dev(self,
412 	    "LUN size: %" PRIu32 " blocks, LUNs: %" PRIu8
413 	    ", total storage size: %" PRIu64 " MB\n",
414 	    chip->nc_lun_blocks, chip->nc_num_luns,
415 	    chip->nc_size / 1024 / 1024);
416 
417 	aprint_normal_dev(self, "column cycles: %" PRIu8 ", row cycles: %"
418 	    PRIu8 ", width: %s\n",
419 	    chip->nc_addr_cycles_column, chip->nc_addr_cycles_row,
420 	    (chip->nc_flags & NC_BUSWIDTH_16) ? "x16" : "x8");
421 
422 	ecc = chip->nc_ecc = &sc->nand_if->ecc;
423 
424 	/*
425 	 * calculate the place of ecc data in oob
426 	 * we try to be compatible with Linux here
427 	 */
428 	switch (chip->nc_spare_size) {
429 	case 8:
430 		ecc->necc_offset = 0;
431 		break;
432 	case 16:
433 		ecc->necc_offset = 0;
434 		break;
435 	case 32:
436 		ecc->necc_offset = 0;
437 		break;
438 	case 64:
439 		ecc->necc_offset = 40;
440 		break;
441 	case 128:
442 		ecc->necc_offset = 80;
443 		break;
444 	default:
445 		panic("OOB size %" PRIu32 " is unexpected", chip->nc_spare_size);
446 	}
447 
448 	ecc->necc_steps = chip->nc_page_size / ecc->necc_block_size;
449 	ecc->necc_size = ecc->necc_steps * ecc->necc_code_size;
450 
451 	/* check if we fit in oob */
452 	if (ecc->necc_offset + ecc->necc_size > chip->nc_spare_size) {
453 		panic("NAND ECC bits dont fit in OOB");
454 	}
455 
456 	/* TODO: mark free oob area available for file systems */
457 
458 	chip->nc_ecc_cache = kmem_zalloc(ecc->necc_size, KM_SLEEP);
459 
460 	/*
461 	 * calculate badblock marker offset in oob
462 	 * we try to be compatible with linux here
463 	 */
464 	if (chip->nc_page_size > 512)
465 		chip->nc_badmarker_offs = 0;
466 	else
467 		chip->nc_badmarker_offs = 5;
468 
469 	/* Calculate page shift and mask */
470 	chip->nc_page_shift = ffs(chip->nc_page_size) - 1;
471 	chip->nc_page_mask = ~(chip->nc_page_size - 1);
472 	/* same for block */
473 	chip->nc_block_shift = ffs(chip->nc_block_size) - 1;
474 	chip->nc_block_mask = ~(chip->nc_block_size - 1);
475 
476 	/* look for quirks here if needed in future */
477 	/* nand_quirks(self, chip); */
478 
479 	return 0;
480 }
481 
482 void
483 nand_read_id(device_t self, uint8_t *manf, uint8_t *dev)
484 {
485 	nand_select(self, true);
486 	nand_command(self, ONFI_READ_ID);
487 	nand_address(self, 0x00);
488 
489 	nand_read_1(self, manf);
490 	nand_read_1(self, dev);
491 
492 	nand_select(self, false);
493 }
494 
495 int
496 nand_read_parameter_page(device_t self, struct onfi_parameter_page *params)
497 {
498 	uint8_t *bufp;
499 	uint16_t crc;
500 	int i;//, tries = 0;
501 
502 	KASSERT(sizeof(*params) == 256);
503 
504 //read_params:
505 //	tries++;
506 
507 	nand_select(self, true);
508 	nand_command(self, ONFI_READ_PARAMETER_PAGE);
509 	nand_address(self, 0x00);
510 
511 	nand_busy(self);
512 
513 	/* TODO check the signature if it contains at least 2 letters */
514 
515 	bufp = (uint8_t *)params;
516 	/* XXX why i am not using read_buf? */
517 	for (i = 0; i < 256; i++) {
518 		nand_read_1(self, &bufp[i]);
519 	}
520 	nand_select(self, false);
521 
522 	/* validate the parameter page with the crc */
523 	crc = nand_crc16(bufp, 254);
524 
525 	if (crc != params->param_integrity_crc) {
526 		aprint_error_dev(self, "parameter page crc check failed\n");
527 		/* TODO: we should read the next parameter page copy */
528 		return 1;
529 	}
530 
531 	return 0;
532 }
533 
534 static int
535 nand_fill_chip_structure(device_t self, struct nand_chip *chip)
536 {
537 	struct onfi_parameter_page params;
538 	uint8_t	vendor[13], model[21];
539 	int i;
540 
541 	if (nand_read_parameter_page(self, &params)) {
542 		return 1;
543 	}
544 
545 	/* strip manufacturer and model string */
546 	strlcpy(vendor, params.param_manufacturer, sizeof(vendor));
547 	for (i = 11; i > 0 && vendor[i] == ' '; i--)
548 		vendor[i] = 0;
549 	strlcpy(model, params.param_model, sizeof(model));
550 	for (i = 19; i > 0 && model[i] == ' '; i--)
551 		model[i] = 0;
552 
553 	aprint_normal_dev(self, "vendor: %s, model: %s\n", vendor, model);
554 
555 	chip->nc_page_size = le32toh(params.param_pagesize);
556 	chip->nc_block_size =
557 	    le32toh(params.param_blocksize) * chip->nc_page_size;
558 	chip->nc_spare_size = le16toh(params.param_sparesize);
559 	chip->nc_lun_blocks = le32toh(params.param_lunsize);
560 	chip->nc_num_luns = params.param_numluns;
561 
562 	chip->nc_size =
563 	    chip->nc_block_size * chip->nc_lun_blocks * chip->nc_num_luns;
564 
565 	/* the lower 4 bits contain the row address cycles */
566 	chip->nc_addr_cycles_row = params.param_addr_cycles & 0x07;
567 	/* the upper 4 bits contain the column address cycles */
568 	chip->nc_addr_cycles_column = (params.param_addr_cycles & ~0x07) >> 4;
569 
570 	uint16_t features = le16toh(params.param_features);
571 	if (features & ONFI_FEATURE_16BIT) {
572 		chip->nc_flags |= NC_BUSWIDTH_16;
573 	}
574 
575 	if (features & ONFI_FEATURE_EXTENDED_PARAM) {
576 		chip->nc_flags |= NC_EXTENDED_PARAM;
577 	}
578 
579 	return 0;
580 }
581 
582 /* ARGSUSED */
583 bool
584 nand_shutdown(device_t self, int howto)
585 {
586 	return true;
587 }
588 
589 static void
590 nand_address_column(device_t self, size_t row, size_t column)
591 {
592 	struct nand_softc *sc = device_private(self);
593 	struct nand_chip *chip = &sc->sc_chip;
594 	uint8_t i;
595 
596 	DPRINTF(("addressing row: 0x%jx column: %" PRIu32 "\n",
597 		(uintmax_t )row, column));
598 
599 	/* XXX TODO */
600 	row >>= chip->nc_page_shift;
601 
602 	/* Write the column (subpage) address */
603 	if (chip->nc_flags & NC_BUSWIDTH_16)
604 		column >>= 1;
605 	for (i = 0; i < chip->nc_addr_cycles_column; i++, column >>= 8)
606 		nand_address(self, column & 0xff);
607 
608 	/* Write the row (page) address */
609 	for (i = 0; i < chip->nc_addr_cycles_row; i++, row >>= 8)
610 		nand_address(self, row & 0xff);
611 }
612 
613 static void
614 nand_address_row(device_t self, size_t row)
615 {
616 	struct nand_softc *sc = device_private(self);
617 	struct nand_chip *chip = &sc->sc_chip;
618 	int i;
619 
620 	/* XXX TODO */
621 	row >>= chip->nc_page_shift;
622 
623 	/* Write the row (page) address */
624 	for (i = 0; i < chip->nc_addr_cycles_row; i++, row >>= 8)
625 		nand_address(self, row & 0xff);
626 }
627 
628 static inline uint8_t
629 nand_get_status(device_t self)
630 {
631 	uint8_t status;
632 
633 	nand_command(self, ONFI_READ_STATUS);
634 	nand_busy(self);
635 	nand_read_1(self, &status);
636 
637 	return status;
638 }
639 
640 static bool
641 nand_check_wp(device_t self)
642 {
643 	if (nand_get_status(self) & 0x80)
644 		return false;
645 	else
646 		return true;
647 }
648 
649 static void
650 nand_prepare_read(device_t self, flash_off_t row, flash_off_t column)
651 {
652 	nand_command(self, ONFI_READ);
653 	nand_address_column(self, row, column);
654 	nand_command(self, ONFI_READ_START);
655 
656 	nand_busy(self);
657 }
658 
659 /* read a page with ecc correction, default implementation */
660 int
661 nand_default_read_page(device_t self, size_t offset, uint8_t *data)
662 {
663 	struct nand_softc *sc = device_private(self);
664 	struct nand_chip *chip = &sc->sc_chip;
665 	size_t b, bs, e, cs;
666 	uint8_t *ecc;
667 	int result;
668 
669 	nand_prepare_read(self, offset, 0);
670 
671 	bs = chip->nc_ecc->necc_block_size;
672 	cs = chip->nc_ecc->necc_code_size;
673 
674 	/* decide if we access by 8 or 16 bits */
675 	if (chip->nc_flags & NC_BUSWIDTH_16) {
676 		for (b = 0, e = 0; b < chip->nc_page_size; b += bs, e += cs) {
677 			nand_ecc_prepare(self, NAND_ECC_READ);
678 			nand_read_buf_2(self, data + b, bs);
679 			nand_ecc_compute(self, data + b,
680 			    chip->nc_ecc_cache + e);
681 		}
682 	} else {
683 		for (b = 0, e = 0; b < chip->nc_page_size; b += bs, e += cs) {
684 			nand_ecc_prepare(self, NAND_ECC_READ);
685 			nand_read_buf_1(self, data + b, bs);
686 			nand_ecc_compute(self, data + b,
687 			    chip->nc_ecc_cache + e);
688 		}
689 	}
690 
691 	/* for debugging new drivers */
692 #if 0
693 	nand_dump_data("page", data, chip->nc_page_size);
694 #endif
695 
696 	nand_read_oob(self, offset, chip->nc_oob_cache);
697 	ecc = chip->nc_oob_cache + chip->nc_ecc->necc_offset;
698 
699 	/* useful for debugging new ecc drivers */
700 #if 0
701 	printf("dumping ecc %d\n--------------\n", chip->nc_ecc->necc_steps);
702 	for (e = 0; e < chip->nc_ecc->necc_steps; e++) {
703 		printf("0x");
704 		for (b = 0; b < cs; b++) {
705 			printf("%.2hhx", ecc[e+b]);
706 		}
707 		printf(" 0x");
708 		for (b = 0; b < cs; b++) {
709 			printf("%.2hhx", chip->nc_ecc_cache[e+b]);
710 		}
711 		printf("\n");
712 	}
713 	printf("--------------\n");
714 #endif
715 
716 	for (b = 0, e = 0; b < chip->nc_page_size; b += bs, e += cs) {
717 		result = nand_ecc_correct(self, data + b, ecc + e,
718 		    chip->nc_ecc_cache + e);
719 
720 		switch (result) {
721 		case NAND_ECC_OK:
722 			break;
723 		case NAND_ECC_CORRECTED:
724 			aprint_error_dev(self,
725 			    "data corrected with ECC at page offset 0x%jx "
726 			    "block %zu\n", (uintmax_t)offset, b);
727 			break;
728 		case NAND_ECC_TWOBIT:
729 			aprint_error_dev(self,
730 			    "uncorrectable ECC error at page offset 0x%jx "
731 			    "block %zu\n", (uintmax_t)offset, b);
732 			return EIO;
733 			break;
734 		case NAND_ECC_INVALID:
735 			aprint_error_dev(self,
736 			    "invalid ECC in oob at page offset 0x%jx "
737 			    "block %zu\n", (uintmax_t)offset, b);
738 			return EIO;
739 			break;
740 		default:
741 			panic("invalid ECC correction errno");
742 		}
743 	}
744 
745 	return 0;
746 }
747 
748 int
749 nand_default_program_page(device_t self, size_t page, const uint8_t *data)
750 {
751 	struct nand_softc *sc = device_private(self);
752 	struct nand_chip *chip = &sc->sc_chip;
753 	size_t bs, cs, e, b;
754 	uint8_t status;
755 	uint8_t *ecc;
756 
757 	nand_command(self, ONFI_PAGE_PROGRAM);
758 	nand_address_column(self, page, 0);
759 
760 	nand_busy(self);
761 
762 	bs = chip->nc_ecc->necc_block_size;
763 	cs = chip->nc_ecc->necc_code_size;
764 	ecc = chip->nc_oob_cache + chip->nc_ecc->necc_offset;
765 
766 	/* XXX code duplication */
767 	/* decide if we access by 8 or 16 bits */
768 	if (chip->nc_flags & NC_BUSWIDTH_16) {
769 		for (b = 0, e = 0; b < chip->nc_page_size; b += bs, e += cs) {
770 			nand_ecc_prepare(self, NAND_ECC_WRITE);
771 			nand_write_buf_2(self, data + b, bs);
772 			nand_ecc_compute(self, data + b, ecc + e);
773 		}
774 		/* write oob with ecc correction code */
775 		nand_write_buf_2(self, chip->nc_oob_cache,
776 		    chip->nc_spare_size);
777 	} else {
778 		for (b = 0, e = 0; b < chip->nc_page_size; b += bs, e += cs) {
779 			nand_ecc_prepare(self, NAND_ECC_WRITE);
780 			nand_write_buf_1(self, data + b, bs);
781 			nand_ecc_compute(self, data + b, ecc + e);
782 		}
783 		/* write oob with ecc correction code */
784 		nand_write_buf_1(self, chip->nc_oob_cache,
785 		    chip->nc_spare_size);
786 	}
787 
788 	nand_command(self, ONFI_PAGE_PROGRAM_START);
789 
790 	nand_busy(self);
791 
792 	/* for debugging ecc */
793 #if 0
794 	printf("dumping ecc %d\n--------------\n", chip->nc_ecc->necc_steps);
795 	for (e = 0; e < chip->nc_ecc->necc_steps; e++) {
796 		printf("0x");
797 		for (b = 0; b < cs; b++) {
798 			printf("%.2hhx", ecc[e+b]);
799 		}
800 		printf("\n");
801 	}
802 	printf("--------------\n");
803 #endif
804 
805 	status = nand_get_status(self);
806 	KASSERT(status & ONFI_STATUS_RDY);
807 	if (status & ONFI_STATUS_FAIL) {
808 		aprint_error_dev(self, "page program failed!\n");
809 		return EIO;
810 	}
811 
812 	return 0;
813 }
814 
815 /* read the OOB of a page */
816 int
817 nand_read_oob(device_t self, size_t page, uint8_t *oob)
818 {
819 	struct nand_softc *sc = device_private(self);
820 	struct nand_chip *chip = &sc->sc_chip;
821 
822 	nand_prepare_read(self, page, chip->nc_page_size);
823 
824 	if (chip->nc_flags & NC_BUSWIDTH_16)
825 		nand_read_buf_2(self, oob, chip->nc_spare_size);
826 	else
827 		nand_read_buf_1(self, oob, chip->nc_spare_size);
828 
829 	/* for debugging drivers */
830 #if 0
831 	nand_dump_data("oob", oob, chip->nc_spare_size);
832 #endif
833 
834 	return 0;
835 }
836 
837 static int
838 nand_write_oob(device_t self, size_t offset, const void *oob)
839 {
840 	struct nand_softc *sc = device_private(self);
841 	struct nand_chip *chip = &sc->sc_chip;
842 	uint8_t status;
843 
844 	nand_command(self, ONFI_PAGE_PROGRAM);
845 	nand_address_column(self, offset, chip->nc_page_size);
846 	nand_command(self, ONFI_PAGE_PROGRAM_START);
847 
848 	nand_busy(self);
849 
850 	if (chip->nc_flags & NC_BUSWIDTH_16)
851 		nand_write_buf_2(self, oob, chip->nc_spare_size);
852 	else
853 		nand_write_buf_1(self, oob, chip->nc_spare_size);
854 
855 	status = nand_get_status(self);
856 	KASSERT(status & ONFI_STATUS_RDY);
857 	if (status & ONFI_STATUS_FAIL)
858 		return EIO;
859 	else
860 		return 0;
861 }
862 
863 void
864 nand_markbad(device_t self, size_t offset)
865 {
866 	struct nand_softc *sc = device_private(self);
867 	struct nand_chip *chip = &sc->sc_chip;
868 	flash_off_t blockoffset;
869 #ifdef NAND_BBT
870 	flash_off_t block;
871 
872 	block = offset / chip->nc_block_size;
873 
874 	nand_bbt_block_markbad(self, block);
875 #endif
876 	blockoffset = offset & chip->nc_block_mask;
877 
878 	/* check if it is already marked bad */
879 	if (nand_isbad(self, blockoffset))
880 		return;
881 
882 	nand_read_oob(self, blockoffset, chip->nc_oob_cache);
883 
884 	chip->nc_oob_cache[chip->nc_badmarker_offs] = 0x00;
885 	chip->nc_oob_cache[chip->nc_badmarker_offs + 1] = 0x00;
886 
887 	nand_write_oob(self, blockoffset, chip->nc_oob_cache);
888 }
889 
890 bool
891 nand_isfactorybad(device_t self, flash_off_t offset)
892 {
893 	struct nand_softc *sc = device_private(self);
894 	struct nand_chip *chip = &sc->sc_chip;
895 	flash_off_t block, first_page, last_page, page;
896 	int i;
897 
898 	/* Check for factory bad blocks first
899 	 * Factory bad blocks are marked in the first or last
900 	 * page of the blocks, see: ONFI 2.2, 3.2.2.
901 	 */
902 	block = offset / chip->nc_block_size;
903 	first_page = block * chip->nc_block_size;
904 	last_page = (block + 1) * chip->nc_block_size
905 	    - chip->nc_page_size;
906 
907 	for (i = 0, page = first_page; i < 2; i++, page = last_page) {
908 		/* address OOB */
909 		nand_prepare_read(self, page, chip->nc_page_size);
910 
911 		if (chip->nc_flags & NC_BUSWIDTH_16) {
912 			uint16_t word;
913 			nand_read_2(self, &word);
914 			if (word == 0x0000)
915 				return true;
916 		} else {
917 			uint8_t byte;
918 			nand_read_1(self, &byte);
919 			if (byte == 0x00)
920 				return true;
921 		}
922 	}
923 
924 	return false;
925 }
926 
927 bool
928 nand_iswornoutbad(device_t self, flash_off_t offset)
929 {
930 	struct nand_softc *sc = device_private(self);
931 	struct nand_chip *chip = &sc->sc_chip;
932 	flash_off_t block;
933 
934 	/* we inspect the first page of the block */
935 	block = offset & chip->nc_block_mask;
936 
937 	/* Linux/u-boot compatible badblock handling */
938 	if (chip->nc_flags & NC_BUSWIDTH_16) {
939 		uint16_t word, mark;
940 
941 		nand_prepare_read(self, block,
942 		    chip->nc_page_size + (chip->nc_badmarker_offs & 0xfe));
943 
944 		nand_read_2(self, &word);
945 		mark = htole16(word);
946 		if (chip->nc_badmarker_offs & 0x01)
947 			mark >>= 8;
948 		if ((mark & 0xff) != 0xff)
949 			return true;
950 	} else {
951 		uint8_t byte;
952 
953 		nand_prepare_read(self, block,
954 		    chip->nc_page_size + chip->nc_badmarker_offs);
955 
956 		nand_read_1(self, &byte);
957 		if (byte != 0xff)
958 			return true;
959 	}
960 
961 	return false;
962 }
963 
964 bool
965 nand_isbad(device_t self, flash_off_t offset)
966 {
967 #ifdef NAND_BBT
968 	struct nand_softc *sc = device_private(self);
969 	struct nand_chip *chip = &sc->sc_chip;
970 	flash_off_t block;
971 
972 	block = offset / chip->nc_block_size;
973 
974 	return nand_bbt_block_isbad(self, block);
975 #else
976 	/* ONFI host requirement */
977 	if (nand_isfactorybad(self, offset))
978 		return true;
979 
980 	/* Look for Linux/U-Boot compatible bad marker */
981 	if (nand_iswornoutbad(self, offset))
982 		return true;
983 
984 	return false;
985 #endif
986 }
987 
988 int
989 nand_erase_block(device_t self, size_t offset)
990 {
991 	uint8_t status;
992 
993 	/* xxx calculate first page of block for address? */
994 
995 	nand_command(self, ONFI_BLOCK_ERASE);
996 	nand_address_row(self, offset);
997 	nand_command(self, ONFI_BLOCK_ERASE_START);
998 
999 	nand_busy(self);
1000 
1001 	status = nand_get_status(self);
1002 	KASSERT(status & ONFI_STATUS_RDY);
1003 	if (status & ONFI_STATUS_FAIL) {
1004 		aprint_error_dev(self, "block erase failed!\n");
1005 		nand_markbad(self, offset);
1006 		return EIO;
1007 	} else {
1008 		return 0;
1009 	}
1010 }
1011 
1012 /* default functions for driver development */
1013 
1014 /* default ECC using hamming code of 256 byte chunks */
1015 int
1016 nand_default_ecc_compute(device_t self, const uint8_t *data, uint8_t *code)
1017 {
1018 	hamming_compute_256(data, code);
1019 
1020 	return 0;
1021 }
1022 
1023 int
1024 nand_default_ecc_correct(device_t self, uint8_t *data, const uint8_t *origcode,
1025 	const uint8_t *compcode)
1026 {
1027 	return hamming_correct_256(data, origcode, compcode);
1028 }
1029 
1030 void
1031 nand_default_select(device_t self, bool enable)
1032 {
1033 	/* do nothing */
1034 	return;
1035 }
1036 
1037 /* implementation of the block device API */
1038 
1039 int
1040 nand_flash_submit(device_t self, struct buf * const bp)
1041 {
1042 	struct nand_softc *sc = device_private(self);
1043 
1044 	return flash_io_submit(&sc->sc_flash_io, bp);
1045 }
1046 
1047 /*
1048  * handle (page) unaligned write to nand
1049  */
1050 static int
1051 nand_flash_write_unaligned(device_t self, flash_off_t offset, size_t len,
1052     size_t *retlen, const uint8_t *buf)
1053 {
1054 	struct nand_softc *sc = device_private(self);
1055 	struct nand_chip *chip = &sc->sc_chip;
1056 	flash_off_t first, last, firstoff;
1057 	const uint8_t *bufp;
1058 	flash_off_t addr;
1059 	size_t left, count;
1060 	int error = 0, i;
1061 
1062 	first = offset & chip->nc_page_mask;
1063 	firstoff = offset & ~chip->nc_page_mask;
1064 	/* XXX check if this should be len - 1 */
1065 	last = (offset + len) & chip->nc_page_mask;
1066 	count = last - first + 1;
1067 
1068 	addr = first;
1069 	*retlen = 0;
1070 
1071 	mutex_enter(&sc->sc_device_lock);
1072 	if (count == 1) {
1073 		if (nand_isbad(self, addr)) {
1074 			aprint_error_dev(self,
1075 			    "nand_flash_write_unaligned: "
1076 			    "bad block encountered\n");
1077 			error = EIO;
1078 			goto out;
1079 		}
1080 
1081 		error = nand_read_page(self, addr, chip->nc_page_cache);
1082 		if (error) {
1083 			goto out;
1084 		}
1085 
1086 		memcpy(chip->nc_page_cache + firstoff, buf, len);
1087 
1088 		error = nand_program_page(self, addr, chip->nc_page_cache);
1089 		if (error) {
1090 			goto out;
1091 		}
1092 
1093 		*retlen = len;
1094 		goto out;
1095 	}
1096 
1097 	bufp = buf;
1098 	left = len;
1099 
1100 	for (i = 0; i < count && left != 0; i++) {
1101 		if (nand_isbad(self, addr)) {
1102 			aprint_error_dev(self,
1103 			    "nand_flash_write_unaligned: "
1104 			    "bad block encountered\n");
1105 			error = EIO;
1106 			goto out;
1107 		}
1108 
1109 		if (i == 0) {
1110 			error = nand_read_page(self,
1111 			    addr, chip->nc_page_cache);
1112 			if (error) {
1113 				goto out;
1114 			}
1115 
1116 			memcpy(chip->nc_page_cache + firstoff,
1117 			    bufp, chip->nc_page_size - firstoff);
1118 
1119 			printf("program page: %s: %d\n", __FILE__, __LINE__);
1120 			error = nand_program_page(self,
1121 			    addr, chip->nc_page_cache);
1122 			if (error) {
1123 				goto out;
1124 			}
1125 
1126 			bufp += chip->nc_page_size - firstoff;
1127 			left -= chip->nc_page_size - firstoff;
1128 			*retlen += chip->nc_page_size - firstoff;
1129 
1130 		} else if (i == count - 1) {
1131 			error = nand_read_page(self,
1132 			    addr, chip->nc_page_cache);
1133 			if (error) {
1134 				goto out;
1135 			}
1136 
1137 			memcpy(chip->nc_page_cache, bufp, left);
1138 
1139 			error = nand_program_page(self,
1140 			    addr, chip->nc_page_cache);
1141 			if (error) {
1142 				goto out;
1143 			}
1144 
1145 			*retlen += left;
1146 			KASSERT(left < chip->nc_page_size);
1147 
1148 		} else {
1149 			/* XXX debug */
1150 			if (left > chip->nc_page_size) {
1151 				printf("left: %zu, i: %d, count: %zu\n",
1152 				    left, i, count);
1153 			}
1154 			KASSERT(left > chip->nc_page_size);
1155 
1156 			error = nand_program_page(self, addr, bufp);
1157 			if (error) {
1158 				goto out;
1159 			}
1160 
1161 			bufp += chip->nc_page_size;
1162 			left -= chip->nc_page_size;
1163 			*retlen += chip->nc_page_size;
1164 		}
1165 
1166 		addr += chip->nc_page_size;
1167 	}
1168 
1169 	KASSERT(*retlen == len);
1170 out:
1171 	mutex_exit(&sc->sc_device_lock);
1172 
1173 	return error;
1174 }
1175 
1176 int
1177 nand_flash_write(device_t self, flash_off_t offset, size_t len, size_t *retlen,
1178     const uint8_t *buf)
1179 {
1180 	struct nand_softc *sc = device_private(self);
1181 	struct nand_chip *chip = &sc->sc_chip;
1182 	const uint8_t *bufp;
1183 	size_t pages, page;
1184 	daddr_t addr;
1185 	int error = 0;
1186 
1187 	if ((offset + len) > chip->nc_size) {
1188 		DPRINTF(("nand_flash_write: write (off: 0x%jx, len: %ju),"
1189 			" is over device size (0x%jx)\n",
1190 			(uintmax_t)offset, (uintmax_t)len,
1191 			(uintmax_t)chip->nc_size));
1192 		return EINVAL;
1193 	}
1194 
1195 	if (len % chip->nc_page_size != 0 ||
1196 	    offset % chip->nc_page_size != 0) {
1197 		return nand_flash_write_unaligned(self,
1198 		    offset, len, retlen, buf);
1199 	}
1200 
1201 	pages = len / chip->nc_page_size;
1202 	KASSERT(pages != 0);
1203 	*retlen = 0;
1204 
1205 	addr = offset;
1206 	bufp = buf;
1207 
1208 	mutex_enter(&sc->sc_device_lock);
1209 	for (page = 0; page < pages; page++) {
1210 		/* do we need this check here? */
1211 		if (nand_isbad(self, addr)) {
1212 			aprint_error_dev(self,
1213 			    "nand_flash_write: bad block encountered\n");
1214 
1215 			error = EIO;
1216 			goto out;
1217 		}
1218 
1219 		error = nand_program_page(self, addr, bufp);
1220 		if (error) {
1221 			goto out;
1222 		}
1223 
1224 		addr += chip->nc_page_size;
1225 		bufp += chip->nc_page_size;
1226 		*retlen += chip->nc_page_size;
1227 	}
1228 out:
1229 	mutex_exit(&sc->sc_device_lock);
1230 	DPRINTF(("page programming: retlen: %" PRIu32 ", len: %" PRIu32 "\n", *retlen, len));
1231 
1232 	return error;
1233 }
1234 
1235 /*
1236  * handle (page) unaligned read from nand
1237  */
1238 static int
1239 nand_flash_read_unaligned(device_t self, size_t offset,
1240     size_t len, size_t *retlen, uint8_t *buf)
1241 {
1242 	struct nand_softc *sc = device_private(self);
1243 	struct nand_chip *chip = &sc->sc_chip;
1244 	daddr_t first, last, count, firstoff;
1245 	uint8_t *bufp;
1246 	daddr_t addr;
1247 	size_t left;
1248 	int error = 0, i;
1249 
1250 	first = offset & chip->nc_page_mask;
1251 	firstoff = offset & ~chip->nc_page_mask;
1252 	last = (offset + len) & chip->nc_page_mask;
1253 	count = (last - first) / chip->nc_page_size + 1;
1254 
1255 	addr = first;
1256 	bufp = buf;
1257 	left = len;
1258 	*retlen = 0;
1259 
1260 	mutex_enter(&sc->sc_device_lock);
1261 	if (count == 1) {
1262 		error = nand_read_page(self, addr, chip->nc_page_cache);
1263 		if (error) {
1264 			goto out;
1265 		}
1266 
1267 		memcpy(bufp, chip->nc_page_cache + firstoff, len);
1268 
1269 		*retlen = len;
1270 		goto out;
1271 	}
1272 
1273 	for (i = 0; i < count && left != 0; i++) {
1274 		error = nand_read_page(self, addr, chip->nc_page_cache);
1275 		if (error) {
1276 			goto out;
1277 		}
1278 
1279 		if (i == 0) {
1280 			memcpy(bufp, chip->nc_page_cache + firstoff,
1281 			    chip->nc_page_size - firstoff);
1282 
1283 			bufp += chip->nc_page_size - firstoff;
1284 			left -= chip->nc_page_size - firstoff;
1285 			*retlen += chip->nc_page_size - firstoff;
1286 
1287 		} else if (i == count - 1) {
1288 			memcpy(bufp, chip->nc_page_cache, left);
1289 			*retlen += left;
1290 			KASSERT(left < chip->nc_page_size);
1291 
1292 		} else {
1293 			memcpy(bufp, chip->nc_page_cache, chip->nc_page_size);
1294 
1295 			bufp += chip->nc_page_size;
1296 			left -= chip->nc_page_size;
1297 			*retlen += chip->nc_page_size;
1298 		}
1299 
1300 		addr += chip->nc_page_size;
1301 	}
1302 	KASSERT(*retlen == len);
1303 out:
1304 	mutex_exit(&sc->sc_device_lock);
1305 
1306 	return error;
1307 }
1308 
1309 int
1310 nand_flash_read(device_t self, flash_off_t offset, size_t len, size_t *retlen,
1311     uint8_t *buf)
1312 {
1313 	struct nand_softc *sc = device_private(self);
1314 	struct nand_chip *chip = &sc->sc_chip;
1315 	uint8_t *bufp;
1316 	size_t addr;
1317 	size_t i, pages;
1318 	int error = 0;
1319 
1320 	*retlen = 0;
1321 
1322 	DPRINTF(("nand_flash_read: off: 0x%jx, len: %" PRIu32 "\n",
1323 		(uintmax_t)offset, len));
1324 
1325 	if (__predict_false((offset + len) > chip->nc_size)) {
1326 		DPRINTF(("nand_flash_read: read (off: 0x%jx, len: %" PRIu32 "),"
1327 			" is over device size (%ju)\n", (uintmax_t)offset,
1328 			len, (uintmax_t)chip->nc_size));
1329 		return EINVAL;
1330 	}
1331 
1332 	/* Handle unaligned access, shouldnt be needed when using the
1333 	 * block device, as strategy handles it, so only low level
1334 	 * accesses will use this path
1335 	 */
1336 	/* XXX^2 */
1337 #if 0
1338 	if (len < chip->nc_page_size)
1339 		panic("TODO page size is larger than read size");
1340 #endif
1341 
1342 	if (len % chip->nc_page_size != 0 ||
1343 	    offset % chip->nc_page_size != 0) {
1344 		return nand_flash_read_unaligned(self,
1345 		    offset, len, retlen, buf);
1346 	}
1347 
1348 	bufp = buf;
1349 	addr = offset;
1350 	pages = len / chip->nc_page_size;
1351 
1352 	mutex_enter(&sc->sc_device_lock);
1353 	for (i = 0; i < pages; i++) {
1354 		/* XXX do we need this check here? */
1355 		if (nand_isbad(self, addr)) {
1356 			aprint_error_dev(self, "bad block encountered\n");
1357 			error = EIO;
1358 			goto out;
1359 		}
1360 		error = nand_read_page(self, addr, bufp);
1361 		if (error)
1362 			goto out;
1363 
1364 		bufp += chip->nc_page_size;
1365 		addr += chip->nc_page_size;
1366 		*retlen += chip->nc_page_size;
1367 	}
1368 out:
1369 	mutex_exit(&sc->sc_device_lock);
1370 
1371 	return error;
1372 }
1373 
1374 int
1375 nand_flash_isbad(device_t self, flash_off_t ofs, bool *is_bad)
1376 {
1377 	struct nand_softc *sc = device_private(self);
1378 	struct nand_chip *chip = &sc->sc_chip;
1379 	bool result;
1380 
1381 	if (ofs > chip->nc_size) {
1382 		DPRINTF(("nand_flash_isbad: offset 0x%jx is larger than"
1383 			" device size (0x%jx)\n", (uintmax_t)ofs,
1384 			(uintmax_t)chip->nc_size));
1385 		return EINVAL;
1386 	}
1387 
1388 	if (ofs % chip->nc_block_size != 0) {
1389 		DPRINTF(("offset (0x%jx) is not a multiple of block size "
1390 			"(%ju)",
1391 			(uintmax_t)ofs, (uintmax_t)chip->nc_block_size));
1392 		return EINVAL;
1393 	}
1394 
1395 	mutex_enter(&sc->sc_device_lock);
1396 	result = nand_isbad(self, ofs);
1397 	mutex_exit(&sc->sc_device_lock);
1398 
1399 	*is_bad = result;
1400 
1401 	return 0;
1402 }
1403 
1404 int
1405 nand_flash_markbad(device_t self, flash_off_t ofs)
1406 {
1407 	struct nand_softc *sc = device_private(self);
1408 	struct nand_chip *chip = &sc->sc_chip;
1409 
1410 	if (ofs > chip->nc_size) {
1411 		DPRINTF(("nand_flash_markbad: offset 0x%jx is larger than"
1412 			" device size (0x%jx)\n", ofs,
1413 			(uintmax_t)chip->nc_size));
1414 		return EINVAL;
1415 	}
1416 
1417 	if (ofs % chip->nc_block_size != 0) {
1418 		panic("offset (%ju) is not a multiple of block size (%ju)",
1419 		    (uintmax_t)ofs, (uintmax_t)chip->nc_block_size);
1420 	}
1421 
1422 	mutex_enter(&sc->sc_device_lock);
1423 	nand_markbad(self, ofs);
1424 	mutex_exit(&sc->sc_device_lock);
1425 
1426 	return 0;
1427 }
1428 
1429 int
1430 nand_flash_erase(device_t self,
1431     struct flash_erase_instruction *ei)
1432 {
1433 	struct nand_softc *sc = device_private(self);
1434 	struct nand_chip *chip = &sc->sc_chip;
1435 	flash_off_t addr;
1436 	int error = 0;
1437 
1438 	if (ei->ei_addr < 0 || ei->ei_len < chip->nc_block_size)
1439 		return EINVAL;
1440 
1441 	if (ei->ei_addr + ei->ei_len > chip->nc_size) {
1442 		DPRINTF(("nand_flash_erase: erase address is over the end"
1443 			" of the device\n"));
1444 		return EINVAL;
1445 	}
1446 
1447 	if (ei->ei_addr % chip->nc_block_size != 0) {
1448 		aprint_error_dev(self,
1449 		    "nand_flash_erase: ei_addr (%ju) is not"
1450 		    " a multiple of block size (%ju)",
1451 		    (uintmax_t)ei->ei_addr,
1452 		    (uintmax_t)chip->nc_block_size);
1453 		return EINVAL;
1454 	}
1455 
1456 	if (ei->ei_len % chip->nc_block_size != 0) {
1457 		aprint_error_dev(self,
1458 		    "nand_flash_erase: ei_len (%ju) is not"
1459 		    " a multiple of block size (%ju)",
1460 		    (uintmax_t)ei->ei_len,
1461 		    (uintmax_t)chip->nc_block_size);
1462 		return EINVAL;
1463 	}
1464 
1465 	mutex_enter(&sc->sc_device_lock);
1466 	addr = ei->ei_addr;
1467 	while (addr < ei->ei_addr + ei->ei_len) {
1468 		if (nand_isbad(self, addr)) {
1469 			aprint_error_dev(self, "bad block encountered\n");
1470 			ei->ei_state = FLASH_ERASE_FAILED;
1471 			error = EIO;
1472 			goto out;
1473 		}
1474 
1475 		error = nand_erase_block(self, addr);
1476 		if (error) {
1477 			ei->ei_state = FLASH_ERASE_FAILED;
1478 			goto out;
1479 		}
1480 
1481 		addr += chip->nc_block_size;
1482 	}
1483 	mutex_exit(&sc->sc_device_lock);
1484 
1485 	ei->ei_state = FLASH_ERASE_DONE;
1486 	if (ei->ei_callback != NULL) {
1487 		ei->ei_callback(ei);
1488 	}
1489 
1490 	return 0;
1491 out:
1492 	mutex_exit(&sc->sc_device_lock);
1493 
1494 	return error;
1495 }
1496 
1497 MODULE(MODULE_CLASS_DRIVER, nand, "flash");
1498 
1499 #ifdef _MODULE
1500 #include "ioconf.c"
1501 #endif
1502 
1503 static int
1504 nand_modcmd(modcmd_t cmd, void *opaque)
1505 {
1506 	switch (cmd) {
1507 	case MODULE_CMD_INIT:
1508 #ifdef _MODULE
1509 		return config_init_component(cfdriver_ioconf_nand,
1510 		    cfattach_ioconf_nand, cfdata_ioconf_nand);
1511 #else
1512 		return 0;
1513 #endif
1514 	case MODULE_CMD_FINI:
1515 #ifdef _MODULE
1516 		return config_fini_component(cfdriver_ioconf_nand,
1517 		    cfattach_ioconf_nand, cfdata_ioconf_nand);
1518 #else
1519 		return 0;
1520 #endif
1521 	default:
1522 		return ENOTTY;
1523 	}
1524 }
1525