1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  Copyright 2017 - Free Electrons
4  *
5  *  Authors:
6  *	Boris Brezillon <boris.brezillon@free-electrons.com>
7  *	Peter Pan <peterpandong@micron.com>
8  */
9 
10 #ifndef __LINUX_MTD_NAND_H
11 #define __LINUX_MTD_NAND_H
12 
13 #include <linux/mtd/mtd.h>
14 
15 /**
16  * struct nand_memory_organization - Memory organization structure
17  * @bits_per_cell: number of bits per NAND cell
18  * @pagesize: page size
19  * @oobsize: OOB area size
20  * @pages_per_eraseblock: number of pages per eraseblock
21  * @eraseblocks_per_lun: number of eraseblocks per LUN (Logical Unit Number)
22  * @planes_per_lun: number of planes per LUN
23  * @luns_per_target: number of LUN per target (target is a synonym for die)
24  * @ntargets: total number of targets exposed by the NAND device
25  */
26 struct nand_memory_organization {
27 	unsigned int bits_per_cell;
28 	unsigned int pagesize;
29 	unsigned int oobsize;
30 	unsigned int pages_per_eraseblock;
31 	unsigned int eraseblocks_per_lun;
32 	unsigned int planes_per_lun;
33 	unsigned int luns_per_target;
34 	unsigned int ntargets;
35 };
36 
37 #define NAND_MEMORG(bpc, ps, os, ppe, epl, ppl, lpt, nt)	\
38 	{							\
39 		.bits_per_cell = (bpc),				\
40 		.pagesize = (ps),				\
41 		.oobsize = (os),				\
42 		.pages_per_eraseblock = (ppe),			\
43 		.eraseblocks_per_lun = (epl),			\
44 		.planes_per_lun = (ppl),			\
45 		.luns_per_target = (lpt),			\
46 		.ntargets = (nt),				\
47 	}
48 
49 /**
50  * struct nand_row_converter - Information needed to convert an absolute offset
51  *			       into a row address
52  * @lun_addr_shift: position of the LUN identifier in the row address
53  * @eraseblock_addr_shift: position of the eraseblock identifier in the row
54  *			   address
55  */
56 struct nand_row_converter {
57 	unsigned int lun_addr_shift;
58 	unsigned int eraseblock_addr_shift;
59 };
60 
61 /**
62  * struct nand_pos - NAND position object
63  * @target: the NAND target/die
64  * @lun: the LUN identifier
65  * @plane: the plane within the LUN
66  * @eraseblock: the eraseblock within the LUN
67  * @page: the page within the LUN
68  *
69  * These information are usually used by specific sub-layers to select the
70  * appropriate target/die and generate a row address to pass to the device.
71  */
72 struct nand_pos {
73 	unsigned int target;
74 	unsigned int lun;
75 	unsigned int plane;
76 	unsigned int eraseblock;
77 	unsigned int page;
78 };
79 
80 /**
81  * struct nand_page_io_req - NAND I/O request object
82  * @pos: the position this I/O request is targeting
83  * @dataoffs: the offset within the page
84  * @datalen: number of data bytes to read from/write to this page
85  * @databuf: buffer to store data in or get data from
86  * @ooboffs: the OOB offset within the page
87  * @ooblen: the number of OOB bytes to read from/write to this page
88  * @oobbuf: buffer to store OOB data in or get OOB data from
89  * @mode: one of the %MTD_OPS_XXX mode
90  *
91  * This object is used to pass per-page I/O requests to NAND sub-layers. This
92  * way all useful information are already formatted in a useful way and
93  * specific NAND layers can focus on translating these information into
94  * specific commands/operations.
95  */
96 struct nand_page_io_req {
97 	struct nand_pos pos;
98 	unsigned int dataoffs;
99 	unsigned int datalen;
100 	union {
101 		const void *out;
102 		void *in;
103 	} databuf;
104 	unsigned int ooboffs;
105 	unsigned int ooblen;
106 	union {
107 		const void *out;
108 		void *in;
109 	} oobbuf;
110 	int mode;
111 };
112 
113 /**
114  * struct nand_ecc_req - NAND ECC requirements
115  * @strength: ECC strength
116  * @step_size: ECC step/block size
117  */
118 struct nand_ecc_req {
119 	unsigned int strength;
120 	unsigned int step_size;
121 };
122 
123 #define NAND_ECCREQ(str, stp) { .strength = (str), .step_size = (stp) }
124 
125 /**
126  * struct nand_bbt - bad block table object
127  * @cache: in memory BBT cache
128  */
129 struct nand_bbt {
130 	unsigned long *cache;
131 };
132 
133 struct nand_device;
134 
135 /**
136  * struct nand_ops - NAND operations
137  * @erase: erase a specific block. No need to check if the block is bad before
138  *	   erasing, this has been taken care of by the generic NAND layer
139  * @markbad: mark a specific block bad. No need to check if the block is
140  *	     already marked bad, this has been taken care of by the generic
141  *	     NAND layer. This method should just write the BBM (Bad Block
142  *	     Marker) so that future call to struct_nand_ops->isbad() return
143  *	     true
144  * @isbad: check whether a block is bad or not. This method should just read
145  *	   the BBM and return whether the block is bad or not based on what it
146  *	   reads
147  *
148  * These are all low level operations that should be implemented by specialized
149  * NAND layers (SPI NAND, raw NAND, ...).
150  */
151 struct nand_ops {
152 	int (*erase)(struct nand_device *nand, const struct nand_pos *pos);
153 	int (*markbad)(struct nand_device *nand, const struct nand_pos *pos);
154 	bool (*isbad)(struct nand_device *nand, const struct nand_pos *pos);
155 };
156 
157 /**
158  * struct nand_device - NAND device
159  * @mtd: MTD instance attached to the NAND device
160  * @memorg: memory layout
161  * @eccreq: ECC requirements
162  * @rowconv: position to row address converter
163  * @bbt: bad block table info
164  * @ops: NAND operations attached to the NAND device
165  *
166  * Generic NAND object. Specialized NAND layers (raw NAND, SPI NAND, OneNAND)
167  * should declare their own NAND object embedding a nand_device struct (that's
168  * how inheritance is done).
169  * struct_nand_device->memorg and struct_nand_device->eccreq should be filled
170  * at device detection time to reflect the NAND device
171  * capabilities/requirements. Once this is done nanddev_init() can be called.
172  * It will take care of converting NAND information into MTD ones, which means
173  * the specialized NAND layers should never manually tweak
174  * struct_nand_device->mtd except for the ->_read/write() hooks.
175  */
176 struct nand_device {
177 	struct mtd_info *mtd;
178 	struct nand_memory_organization memorg;
179 	struct nand_ecc_req eccreq;
180 	struct nand_row_converter rowconv;
181 	struct nand_bbt bbt;
182 	const struct nand_ops *ops;
183 };
184 
185 /**
186  * struct nand_io_iter - NAND I/O iterator
187  * @req: current I/O request
188  * @oobbytes_per_page: maximum number of OOB bytes per page
189  * @dataleft: remaining number of data bytes to read/write
190  * @oobleft: remaining number of OOB bytes to read/write
191  *
192  * Can be used by specialized NAND layers to iterate over all pages covered
193  * by an MTD I/O request, which should greatly simplifies the boiler-plate
194  * code needed to read/write data from/to a NAND device.
195  */
196 struct nand_io_iter {
197 	struct nand_page_io_req req;
198 	unsigned int oobbytes_per_page;
199 	unsigned int dataleft;
200 	unsigned int oobleft;
201 };
202 
203 /**
204  * mtd_to_nanddev() - Get the NAND device attached to the MTD instance
205  * @mtd: MTD instance
206  *
207  * Return: the NAND device embedding @mtd.
208  */
mtd_to_nanddev(struct mtd_info * mtd)209 static inline struct nand_device *mtd_to_nanddev(struct mtd_info *mtd)
210 {
211 	return mtd->priv;
212 }
213 
214 /**
215  * nanddev_to_mtd() - Get the MTD device attached to a NAND device
216  * @nand: NAND device
217  *
218  * Return: the MTD device embedded in @nand.
219  */
nanddev_to_mtd(struct nand_device * nand)220 static inline struct mtd_info *nanddev_to_mtd(struct nand_device *nand)
221 {
222 	return nand->mtd;
223 }
224 
225 /*
226  * nanddev_bits_per_cell() - Get the number of bits per cell
227  * @nand: NAND device
228  *
229  * Return: the number of bits per cell.
230  */
nanddev_bits_per_cell(const struct nand_device * nand)231 static inline unsigned int nanddev_bits_per_cell(const struct nand_device *nand)
232 {
233 	return nand->memorg.bits_per_cell;
234 }
235 
236 /**
237  * nanddev_page_size() - Get NAND page size
238  * @nand: NAND device
239  *
240  * Return: the page size.
241  */
nanddev_page_size(const struct nand_device * nand)242 static inline size_t nanddev_page_size(const struct nand_device *nand)
243 {
244 	return nand->memorg.pagesize;
245 }
246 
247 /**
248  * nanddev_per_page_oobsize() - Get NAND OOB size
249  * @nand: NAND device
250  *
251  * Return: the OOB size.
252  */
253 static inline unsigned int
nanddev_per_page_oobsize(const struct nand_device * nand)254 nanddev_per_page_oobsize(const struct nand_device *nand)
255 {
256 	return nand->memorg.oobsize;
257 }
258 
259 /**
260  * nanddev_pages_per_eraseblock() - Get the number of pages per eraseblock
261  * @nand: NAND device
262  *
263  * Return: the number of pages per eraseblock.
264  */
265 static inline unsigned int
nanddev_pages_per_eraseblock(const struct nand_device * nand)266 nanddev_pages_per_eraseblock(const struct nand_device *nand)
267 {
268 	return nand->memorg.pages_per_eraseblock;
269 }
270 
271 /**
272  * nanddev_per_page_oobsize() - Get NAND erase block size
273  * @nand: NAND device
274  *
275  * Return: the eraseblock size.
276  */
nanddev_eraseblock_size(const struct nand_device * nand)277 static inline size_t nanddev_eraseblock_size(const struct nand_device *nand)
278 {
279 	return nand->memorg.pagesize * nand->memorg.pages_per_eraseblock;
280 }
281 
282 /**
283  * nanddev_eraseblocks_per_lun() - Get the number of eraseblocks per LUN
284  * @nand: NAND device
285  *
286  * Return: the number of eraseblocks per LUN.
287  */
288 static inline unsigned int
nanddev_eraseblocks_per_lun(const struct nand_device * nand)289 nanddev_eraseblocks_per_lun(const struct nand_device *nand)
290 {
291 	return nand->memorg.eraseblocks_per_lun;
292 }
293 
294 /**
295  * nanddev_target_size() - Get the total size provided by a single target/die
296  * @nand: NAND device
297  *
298  * Return: the total size exposed by a single target/die in bytes.
299  */
nanddev_target_size(const struct nand_device * nand)300 static inline u64 nanddev_target_size(const struct nand_device *nand)
301 {
302 	return (u64)nand->memorg.luns_per_target *
303 	       nand->memorg.eraseblocks_per_lun *
304 	       nand->memorg.pages_per_eraseblock *
305 	       nand->memorg.pagesize;
306 }
307 
308 /**
309  * nanddev_ntarget() - Get the total of targets
310  * @nand: NAND device
311  *
312  * Return: the number of targets/dies exposed by @nand.
313  */
nanddev_ntargets(const struct nand_device * nand)314 static inline unsigned int nanddev_ntargets(const struct nand_device *nand)
315 {
316 	return nand->memorg.ntargets;
317 }
318 
319 /**
320  * nanddev_neraseblocks() - Get the total number of erasablocks
321  * @nand: NAND device
322  *
323  * Return: the total number of eraseblocks exposed by @nand.
324  */
nanddev_neraseblocks(const struct nand_device * nand)325 static inline unsigned int nanddev_neraseblocks(const struct nand_device *nand)
326 {
327 	return (u64)nand->memorg.luns_per_target *
328 	       nand->memorg.eraseblocks_per_lun *
329 	       nand->memorg.pages_per_eraseblock;
330 }
331 
332 /**
333  * nanddev_size() - Get NAND size
334  * @nand: NAND device
335  *
336  * Return: the total size (in bytes) exposed by @nand.
337  */
nanddev_size(const struct nand_device * nand)338 static inline u64 nanddev_size(const struct nand_device *nand)
339 {
340 	return nanddev_target_size(nand) * nanddev_ntargets(nand);
341 }
342 
343 /**
344  * nanddev_get_memorg() - Extract memory organization info from a NAND device
345  * @nand: NAND device
346  *
347  * This can be used by the upper layer to fill the memorg info before calling
348  * nanddev_init().
349  *
350  * Return: the memorg object embedded in the NAND device.
351  */
352 static inline struct nand_memory_organization *
nanddev_get_memorg(struct nand_device * nand)353 nanddev_get_memorg(struct nand_device *nand)
354 {
355 	return &nand->memorg;
356 }
357 
358 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
359 		 struct module *owner);
360 void nanddev_cleanup(struct nand_device *nand);
361 
362 /**
363  * nanddev_register() - Register a NAND device
364  * @nand: NAND device
365  *
366  * Register a NAND device.
367  * This function is just a wrapper around mtd_device_register()
368  * registering the MTD device embedded in @nand.
369  *
370  * Return: 0 in case of success, a negative error code otherwise.
371  */
nanddev_register(struct nand_device * nand)372 static inline int nanddev_register(struct nand_device *nand)
373 {
374 	return mtd_device_register(nand->mtd, NULL, 0);
375 }
376 
377 /**
378  * nanddev_unregister() - Unregister a NAND device
379  * @nand: NAND device
380  *
381  * Unregister a NAND device.
382  * This function is just a wrapper around mtd_device_unregister()
383  * unregistering the MTD device embedded in @nand.
384  *
385  * Return: 0 in case of success, a negative error code otherwise.
386  */
nanddev_unregister(struct nand_device * nand)387 static inline int nanddev_unregister(struct nand_device *nand)
388 {
389 	return mtd_device_unregister(nand->mtd);
390 }
391 
392 #ifndef __UBOOT__
393 /**
394  * nanddev_set_of_node() - Attach a DT node to a NAND device
395  * @nand: NAND device
396  * @np: DT node
397  *
398  * Attach a DT node to a NAND device.
399  */
nanddev_set_of_node(struct nand_device * nand,const struct device_node * np)400 static inline void nanddev_set_of_node(struct nand_device *nand,
401 				       const struct device_node *np)
402 {
403 	mtd_set_of_node(nand->mtd, np);
404 }
405 
406 /**
407  * nanddev_get_of_node() - Retrieve the DT node attached to a NAND device
408  * @nand: NAND device
409  *
410  * Return: the DT node attached to @nand.
411  */
nanddev_get_of_node(struct nand_device * nand)412 static inline const struct device_node *nanddev_get_of_node(struct nand_device *nand)
413 {
414 	return mtd_get_of_node(nand->mtd);
415 }
416 #else
417 /**
418  * nanddev_set_of_node() - Attach a DT node to a NAND device
419  * @nand: NAND device
420  * @node: ofnode
421  *
422  * Attach a DT node to a NAND device.
423  */
nanddev_set_ofnode(struct nand_device * nand,ofnode node)424 static inline void nanddev_set_ofnode(struct nand_device *nand, ofnode node)
425 {
426 	mtd_set_ofnode(nand->mtd, node);
427 }
428 #endif /* __UBOOT__ */
429 
430 /**
431  * nanddev_offs_to_pos() - Convert an absolute NAND offset into a NAND position
432  * @nand: NAND device
433  * @offs: absolute NAND offset (usually passed by the MTD layer)
434  * @pos: a NAND position object to fill in
435  *
436  * Converts @offs into a nand_pos representation.
437  *
438  * Return: the offset within the NAND page pointed by @pos.
439  */
nanddev_offs_to_pos(struct nand_device * nand,loff_t offs,struct nand_pos * pos)440 static inline unsigned int nanddev_offs_to_pos(struct nand_device *nand,
441 					       loff_t offs,
442 					       struct nand_pos *pos)
443 {
444 	unsigned int pageoffs;
445 	u64 tmp = offs;
446 
447 	pageoffs = do_div(tmp, nand->memorg.pagesize);
448 	pos->page = do_div(tmp, nand->memorg.pages_per_eraseblock);
449 	pos->eraseblock = do_div(tmp, nand->memorg.eraseblocks_per_lun);
450 	pos->plane = pos->eraseblock % nand->memorg.planes_per_lun;
451 	pos->lun = do_div(tmp, nand->memorg.luns_per_target);
452 	pos->target = tmp;
453 
454 	return pageoffs;
455 }
456 
457 /**
458  * nanddev_pos_cmp() - Compare two NAND positions
459  * @a: First NAND position
460  * @b: Second NAND position
461  *
462  * Compares two NAND positions.
463  *
464  * Return: -1 if @a < @b, 0 if @a == @b and 1 if @a > @b.
465  */
nanddev_pos_cmp(const struct nand_pos * a,const struct nand_pos * b)466 static inline int nanddev_pos_cmp(const struct nand_pos *a,
467 				  const struct nand_pos *b)
468 {
469 	if (a->target != b->target)
470 		return a->target < b->target ? -1 : 1;
471 
472 	if (a->lun != b->lun)
473 		return a->lun < b->lun ? -1 : 1;
474 
475 	if (a->eraseblock != b->eraseblock)
476 		return a->eraseblock < b->eraseblock ? -1 : 1;
477 
478 	if (a->page != b->page)
479 		return a->page < b->page ? -1 : 1;
480 
481 	return 0;
482 }
483 
484 /**
485  * nanddev_pos_to_offs() - Convert a NAND position into an absolute offset
486  * @nand: NAND device
487  * @pos: the NAND position to convert
488  *
489  * Converts @pos NAND position into an absolute offset.
490  *
491  * Return: the absolute offset. Note that @pos points to the beginning of a
492  *	   page, if one wants to point to a specific offset within this page
493  *	   the returned offset has to be adjusted manually.
494  */
nanddev_pos_to_offs(struct nand_device * nand,const struct nand_pos * pos)495 static inline loff_t nanddev_pos_to_offs(struct nand_device *nand,
496 					 const struct nand_pos *pos)
497 {
498 	unsigned int npages;
499 
500 	npages = pos->page +
501 		 ((pos->eraseblock +
502 		   (pos->lun +
503 		    (pos->target * nand->memorg.luns_per_target)) *
504 		   nand->memorg.eraseblocks_per_lun) *
505 		  nand->memorg.pages_per_eraseblock);
506 
507 	return (loff_t)npages * nand->memorg.pagesize;
508 }
509 
510 /**
511  * nanddev_pos_to_row() - Extract a row address from a NAND position
512  * @nand: NAND device
513  * @pos: the position to convert
514  *
515  * Converts a NAND position into a row address that can then be passed to the
516  * device.
517  *
518  * Return: the row address extracted from @pos.
519  */
nanddev_pos_to_row(struct nand_device * nand,const struct nand_pos * pos)520 static inline unsigned int nanddev_pos_to_row(struct nand_device *nand,
521 					      const struct nand_pos *pos)
522 {
523 	return (pos->lun << nand->rowconv.lun_addr_shift) |
524 	       (pos->eraseblock << nand->rowconv.eraseblock_addr_shift) |
525 	       pos->page;
526 }
527 
528 /**
529  * nanddev_pos_next_target() - Move a position to the next target/die
530  * @nand: NAND device
531  * @pos: the position to update
532  *
533  * Updates @pos to point to the start of the next target/die. Useful when you
534  * want to iterate over all targets/dies of a NAND device.
535  */
nanddev_pos_next_target(struct nand_device * nand,struct nand_pos * pos)536 static inline void nanddev_pos_next_target(struct nand_device *nand,
537 					   struct nand_pos *pos)
538 {
539 	pos->page = 0;
540 	pos->plane = 0;
541 	pos->eraseblock = 0;
542 	pos->lun = 0;
543 	pos->target++;
544 }
545 
546 /**
547  * nanddev_pos_next_lun() - Move a position to the next LUN
548  * @nand: NAND device
549  * @pos: the position to update
550  *
551  * Updates @pos to point to the start of the next LUN. Useful when you want to
552  * iterate over all LUNs of a NAND device.
553  */
nanddev_pos_next_lun(struct nand_device * nand,struct nand_pos * pos)554 static inline void nanddev_pos_next_lun(struct nand_device *nand,
555 					struct nand_pos *pos)
556 {
557 	if (pos->lun >= nand->memorg.luns_per_target - 1)
558 		return nanddev_pos_next_target(nand, pos);
559 
560 	pos->lun++;
561 	pos->page = 0;
562 	pos->plane = 0;
563 	pos->eraseblock = 0;
564 }
565 
566 /**
567  * nanddev_pos_next_eraseblock() - Move a position to the next eraseblock
568  * @nand: NAND device
569  * @pos: the position to update
570  *
571  * Updates @pos to point to the start of the next eraseblock. Useful when you
572  * want to iterate over all eraseblocks of a NAND device.
573  */
nanddev_pos_next_eraseblock(struct nand_device * nand,struct nand_pos * pos)574 static inline void nanddev_pos_next_eraseblock(struct nand_device *nand,
575 					       struct nand_pos *pos)
576 {
577 	if (pos->eraseblock >= nand->memorg.eraseblocks_per_lun - 1)
578 		return nanddev_pos_next_lun(nand, pos);
579 
580 	pos->eraseblock++;
581 	pos->page = 0;
582 	pos->plane = pos->eraseblock % nand->memorg.planes_per_lun;
583 }
584 
585 /**
586  * nanddev_pos_next_eraseblock() - Move a position to the next page
587  * @nand: NAND device
588  * @pos: the position to update
589  *
590  * Updates @pos to point to the start of the next page. Useful when you want to
591  * iterate over all pages of a NAND device.
592  */
nanddev_pos_next_page(struct nand_device * nand,struct nand_pos * pos)593 static inline void nanddev_pos_next_page(struct nand_device *nand,
594 					 struct nand_pos *pos)
595 {
596 	if (pos->page >= nand->memorg.pages_per_eraseblock - 1)
597 		return nanddev_pos_next_eraseblock(nand, pos);
598 
599 	pos->page++;
600 }
601 
602 /**
603  * nand_io_iter_init - Initialize a NAND I/O iterator
604  * @nand: NAND device
605  * @offs: absolute offset
606  * @req: MTD request
607  * @iter: NAND I/O iterator
608  *
609  * Initializes a NAND iterator based on the information passed by the MTD
610  * layer.
611  */
nanddev_io_iter_init(struct nand_device * nand,loff_t offs,struct mtd_oob_ops * req,struct nand_io_iter * iter)612 static inline void nanddev_io_iter_init(struct nand_device *nand,
613 					loff_t offs, struct mtd_oob_ops *req,
614 					struct nand_io_iter *iter)
615 {
616 	struct mtd_info *mtd = nanddev_to_mtd(nand);
617 
618 	iter->req.mode = req->mode;
619 	iter->req.dataoffs = nanddev_offs_to_pos(nand, offs, &iter->req.pos);
620 	iter->req.ooboffs = req->ooboffs;
621 	iter->oobbytes_per_page = mtd_oobavail(mtd, req);
622 	iter->dataleft = req->len;
623 	iter->oobleft = req->ooblen;
624 	iter->req.databuf.in = req->datbuf;
625 	iter->req.datalen = min_t(unsigned int,
626 				  nand->memorg.pagesize - iter->req.dataoffs,
627 				  iter->dataleft);
628 	iter->req.oobbuf.in = req->oobbuf;
629 	iter->req.ooblen = min_t(unsigned int,
630 				 iter->oobbytes_per_page - iter->req.ooboffs,
631 				 iter->oobleft);
632 }
633 
634 /**
635  * nand_io_iter_next_page - Move to the next page
636  * @nand: NAND device
637  * @iter: NAND I/O iterator
638  *
639  * Updates the @iter to point to the next page.
640  */
nanddev_io_iter_next_page(struct nand_device * nand,struct nand_io_iter * iter)641 static inline void nanddev_io_iter_next_page(struct nand_device *nand,
642 					     struct nand_io_iter *iter)
643 {
644 	nanddev_pos_next_page(nand, &iter->req.pos);
645 	iter->dataleft -= iter->req.datalen;
646 	iter->req.databuf.in += iter->req.datalen;
647 	iter->oobleft -= iter->req.ooblen;
648 	iter->req.oobbuf.in += iter->req.ooblen;
649 	iter->req.dataoffs = 0;
650 	iter->req.ooboffs = 0;
651 	iter->req.datalen = min_t(unsigned int, nand->memorg.pagesize,
652 				  iter->dataleft);
653 	iter->req.ooblen = min_t(unsigned int, iter->oobbytes_per_page,
654 				 iter->oobleft);
655 }
656 
657 /**
658  * nand_io_iter_end - Should end iteration or not
659  * @nand: NAND device
660  * @iter: NAND I/O iterator
661  *
662  * Check whether @iter has reached the end of the NAND portion it was asked to
663  * iterate on or not.
664  *
665  * Return: true if @iter has reached the end of the iteration request, false
666  *	   otherwise.
667  */
nanddev_io_iter_end(struct nand_device * nand,const struct nand_io_iter * iter)668 static inline bool nanddev_io_iter_end(struct nand_device *nand,
669 				       const struct nand_io_iter *iter)
670 {
671 	if (iter->dataleft || iter->oobleft)
672 		return false;
673 
674 	return true;
675 }
676 
677 /**
678  * nand_io_for_each_page - Iterate over all NAND pages contained in an MTD I/O
679  *			   request
680  * @nand: NAND device
681  * @start: start address to read/write from
682  * @req: MTD I/O request
683  * @iter: NAND I/O iterator
684  *
685  * Should be used for iterate over pages that are contained in an MTD request.
686  */
687 #define nanddev_io_for_each_page(nand, start, req, iter)		\
688 	for (nanddev_io_iter_init(nand, start, req, iter);		\
689 	     !nanddev_io_iter_end(nand, iter);				\
690 	     nanddev_io_iter_next_page(nand, iter))
691 
692 bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos);
693 bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos);
694 int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos);
695 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos);
696 
697 /* BBT related functions */
698 enum nand_bbt_block_status {
699 	NAND_BBT_BLOCK_STATUS_UNKNOWN,
700 	NAND_BBT_BLOCK_GOOD,
701 	NAND_BBT_BLOCK_WORN,
702 	NAND_BBT_BLOCK_RESERVED,
703 	NAND_BBT_BLOCK_FACTORY_BAD,
704 	NAND_BBT_BLOCK_NUM_STATUS,
705 };
706 
707 int nanddev_bbt_init(struct nand_device *nand);
708 void nanddev_bbt_cleanup(struct nand_device *nand);
709 int nanddev_bbt_update(struct nand_device *nand);
710 int nanddev_bbt_get_block_status(const struct nand_device *nand,
711 				 unsigned int entry);
712 int nanddev_bbt_set_block_status(struct nand_device *nand, unsigned int entry,
713 				 enum nand_bbt_block_status status);
714 int nanddev_bbt_markbad(struct nand_device *nand, unsigned int block);
715 
716 /**
717  * nanddev_bbt_pos_to_entry() - Convert a NAND position into a BBT entry
718  * @nand: NAND device
719  * @pos: the NAND position we want to get BBT entry for
720  *
721  * Return the BBT entry used to store information about the eraseblock pointed
722  * by @pos.
723  *
724  * Return: the BBT entry storing information about eraseblock pointed by @pos.
725  */
nanddev_bbt_pos_to_entry(struct nand_device * nand,const struct nand_pos * pos)726 static inline unsigned int nanddev_bbt_pos_to_entry(struct nand_device *nand,
727 						    const struct nand_pos *pos)
728 {
729 	return pos->eraseblock +
730 	       ((pos->lun + (pos->target * nand->memorg.luns_per_target)) *
731 		nand->memorg.eraseblocks_per_lun);
732 }
733 
734 /**
735  * nanddev_bbt_is_initialized() - Check if the BBT has been initialized
736  * @nand: NAND device
737  *
738  * Return: true if the BBT has been initialized, false otherwise.
739  */
nanddev_bbt_is_initialized(struct nand_device * nand)740 static inline bool nanddev_bbt_is_initialized(struct nand_device *nand)
741 {
742 	return !!nand->bbt.cache;
743 }
744 
745 /* MTD -> NAND helper functions. */
746 int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo);
747 
748 #endif /* __LINUX_MTD_NAND_H */
749