xref: /openbmc/u-boot/drivers/mtd/nand/core.c (revision e246b728)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2017 Free Electrons
4  *
5  * Authors:
6  *	Boris Brezillon <boris.brezillon@free-electrons.com>
7  *	Peter Pan <peterpandong@micron.com>
8  */
9 
10 #define pr_fmt(fmt)	"nand: " fmt
11 
12 #ifndef __UBOOT__
13 #include <linux/module.h>
14 #endif
15 #include <linux/mtd/nand.h>
16 
17 /**
18  * nanddev_isbad() - Check if a block is bad
19  * @nand: NAND device
20  * @pos: position pointing to the block we want to check
21  *
22  * Return: true if the block is bad, false otherwise.
23  */
24 bool nanddev_isbad(struct nand_device *nand, const struct nand_pos *pos)
25 {
26 	if (nanddev_bbt_is_initialized(nand)) {
27 		unsigned int entry;
28 		int status;
29 
30 		entry = nanddev_bbt_pos_to_entry(nand, pos);
31 		status = nanddev_bbt_get_block_status(nand, entry);
32 		/* Lazy block status retrieval */
33 		if (status == NAND_BBT_BLOCK_STATUS_UNKNOWN) {
34 			if (nand->ops->isbad(nand, pos))
35 				status = NAND_BBT_BLOCK_FACTORY_BAD;
36 			else
37 				status = NAND_BBT_BLOCK_GOOD;
38 
39 			nanddev_bbt_set_block_status(nand, entry, status);
40 		}
41 
42 		if (status == NAND_BBT_BLOCK_WORN ||
43 		    status == NAND_BBT_BLOCK_FACTORY_BAD)
44 			return true;
45 
46 		return false;
47 	}
48 
49 	return nand->ops->isbad(nand, pos);
50 }
51 EXPORT_SYMBOL_GPL(nanddev_isbad);
52 
53 /**
54  * nanddev_markbad() - Mark a block as bad
55  * @nand: NAND device
56  * @pos: position of the block to mark bad
57  *
58  * Mark a block bad. This function is updating the BBT if available and
59  * calls the low-level markbad hook (nand->ops->markbad()).
60  *
61  * Return: 0 in case of success, a negative error code otherwise.
62  */
63 int nanddev_markbad(struct nand_device *nand, const struct nand_pos *pos)
64 {
65 	struct mtd_info *mtd = nanddev_to_mtd(nand);
66 	unsigned int entry;
67 	int ret = 0;
68 
69 	if (nanddev_isbad(nand, pos))
70 		return 0;
71 
72 	ret = nand->ops->markbad(nand, pos);
73 	if (ret)
74 		pr_warn("failed to write BBM to block @%llx (err = %d)\n",
75 			nanddev_pos_to_offs(nand, pos), ret);
76 
77 	if (!nanddev_bbt_is_initialized(nand))
78 		goto out;
79 
80 	entry = nanddev_bbt_pos_to_entry(nand, pos);
81 	ret = nanddev_bbt_set_block_status(nand, entry, NAND_BBT_BLOCK_WORN);
82 	if (ret)
83 		goto out;
84 
85 	ret = nanddev_bbt_update(nand);
86 
87 out:
88 	if (!ret)
89 		mtd->ecc_stats.badblocks++;
90 
91 	return ret;
92 }
93 EXPORT_SYMBOL_GPL(nanddev_markbad);
94 
95 /**
96  * nanddev_isreserved() - Check whether an eraseblock is reserved or not
97  * @nand: NAND device
98  * @pos: NAND position to test
99  *
100  * Checks whether the eraseblock pointed by @pos is reserved or not.
101  *
102  * Return: true if the eraseblock is reserved, false otherwise.
103  */
104 bool nanddev_isreserved(struct nand_device *nand, const struct nand_pos *pos)
105 {
106 	unsigned int entry;
107 	int status;
108 
109 	if (!nanddev_bbt_is_initialized(nand))
110 		return false;
111 
112 	/* Return info from the table */
113 	entry = nanddev_bbt_pos_to_entry(nand, pos);
114 	status = nanddev_bbt_get_block_status(nand, entry);
115 	return status == NAND_BBT_BLOCK_RESERVED;
116 }
117 EXPORT_SYMBOL_GPL(nanddev_isreserved);
118 
119 /**
120  * nanddev_erase() - Erase a NAND portion
121  * @nand: NAND device
122  * @pos: position of the block to erase
123  *
124  * Erases the block if it's not bad.
125  *
126  * Return: 0 in case of success, a negative error code otherwise.
127  */
128 int nanddev_erase(struct nand_device *nand, const struct nand_pos *pos)
129 {
130 	if (nanddev_isbad(nand, pos) || nanddev_isreserved(nand, pos)) {
131 		pr_warn("attempt to erase a bad/reserved block @%llx\n",
132 			nanddev_pos_to_offs(nand, pos));
133 		return -EIO;
134 	}
135 
136 	return nand->ops->erase(nand, pos);
137 }
138 EXPORT_SYMBOL_GPL(nanddev_erase);
139 
140 /**
141  * nanddev_mtd_erase() - Generic mtd->_erase() implementation for NAND devices
142  * @mtd: MTD device
143  * @einfo: erase request
144  *
145  * This is a simple mtd->_erase() implementation iterating over all blocks
146  * concerned by @einfo and calling nand->ops->erase() on each of them.
147  *
148  * Note that mtd->_erase should not be directly assigned to this helper,
149  * because there's no locking here. NAND specialized layers should instead
150  * implement there own wrapper around nanddev_mtd_erase() taking the
151  * appropriate lock before calling nanddev_mtd_erase().
152  *
153  * Return: 0 in case of success, a negative error code otherwise.
154  */
155 int nanddev_mtd_erase(struct mtd_info *mtd, struct erase_info *einfo)
156 {
157 	struct nand_device *nand = mtd_to_nanddev(mtd);
158 	struct nand_pos pos, last;
159 	int ret;
160 
161 	nanddev_offs_to_pos(nand, einfo->addr, &pos);
162 	nanddev_offs_to_pos(nand, einfo->addr + einfo->len - 1, &last);
163 	while (nanddev_pos_cmp(&pos, &last) <= 0) {
164 		ret = nanddev_erase(nand, &pos);
165 		if (ret) {
166 			einfo->fail_addr = nanddev_pos_to_offs(nand, &pos);
167 
168 			return ret;
169 		}
170 
171 		nanddev_pos_next_eraseblock(nand, &pos);
172 	}
173 
174 	return 0;
175 }
176 EXPORT_SYMBOL_GPL(nanddev_mtd_erase);
177 
178 /**
179  * nanddev_init() - Initialize a NAND device
180  * @nand: NAND device
181  * @ops: NAND device operations
182  * @owner: NAND device owner
183  *
184  * Initializes a NAND device object. Consistency checks are done on @ops and
185  * @nand->memorg. Also takes care of initializing the BBT.
186  *
187  * Return: 0 in case of success, a negative error code otherwise.
188  */
189 int nanddev_init(struct nand_device *nand, const struct nand_ops *ops,
190 		 struct module *owner)
191 {
192 	struct mtd_info *mtd = nanddev_to_mtd(nand);
193 	struct nand_memory_organization *memorg = nanddev_get_memorg(nand);
194 
195 	if (!nand || !ops)
196 		return -EINVAL;
197 
198 	if (!ops->erase || !ops->markbad || !ops->isbad)
199 		return -EINVAL;
200 
201 	if (!memorg->bits_per_cell || !memorg->pagesize ||
202 	    !memorg->pages_per_eraseblock || !memorg->eraseblocks_per_lun ||
203 	    !memorg->planes_per_lun || !memorg->luns_per_target ||
204 	    !memorg->ntargets)
205 		return -EINVAL;
206 
207 	nand->rowconv.eraseblock_addr_shift =
208 					fls(memorg->pages_per_eraseblock - 1);
209 	nand->rowconv.lun_addr_shift = fls(memorg->eraseblocks_per_lun - 1) +
210 				       nand->rowconv.eraseblock_addr_shift;
211 
212 	nand->ops = ops;
213 
214 	mtd->type = memorg->bits_per_cell == 1 ?
215 		    MTD_NANDFLASH : MTD_MLCNANDFLASH;
216 	mtd->flags = MTD_CAP_NANDFLASH;
217 	mtd->erasesize = memorg->pagesize * memorg->pages_per_eraseblock;
218 	mtd->writesize = memorg->pagesize;
219 	mtd->writebufsize = memorg->pagesize;
220 	mtd->oobsize = memorg->oobsize;
221 	mtd->size = nanddev_size(nand);
222 	mtd->owner = owner;
223 
224 	return nanddev_bbt_init(nand);
225 }
226 EXPORT_SYMBOL_GPL(nanddev_init);
227 
228 /**
229  * nanddev_cleanup() - Release resources allocated in nanddev_init()
230  * @nand: NAND device
231  *
232  * Basically undoes what has been done in nanddev_init().
233  */
234 void nanddev_cleanup(struct nand_device *nand)
235 {
236 	if (nanddev_bbt_is_initialized(nand))
237 		nanddev_bbt_cleanup(nand);
238 }
239 EXPORT_SYMBOL_GPL(nanddev_cleanup);
240 
241 MODULE_DESCRIPTION("Generic NAND framework");
242 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
243 MODULE_LICENSE("GPL v2");
244