1 /*
2 * Copyright (C) 2017 Free Electrons
3 * Copyright (C) 2017 NextThing Co
4 *
5 * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 */
17
18 #include <linux/mtd/rawnand.h>
19
toshiba_nand_decode_id(struct nand_chip * chip)20 static void toshiba_nand_decode_id(struct nand_chip *chip)
21 {
22 struct mtd_info *mtd = nand_to_mtd(chip);
23
24 nand_decode_ext_id(chip);
25
26 /*
27 * Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per
28 * 512B page. For Toshiba SLC, we decode the 5th/6th byte as
29 * follows:
30 * - ID byte 6, bits[2:0]: 100b -> 43nm, 101b -> 32nm,
31 * 110b -> 24nm
32 * - ID byte 5, bit[7]: 1 -> BENAND, 0 -> raw SLC
33 */
34 if (chip->id.len >= 6 && nand_is_slc(chip) &&
35 (chip->id.data[5] & 0x7) == 0x6 /* 24nm */ &&
36 !(chip->id.data[4] & 0x80) /* !BENAND */)
37 mtd->oobsize = 32 * mtd->writesize >> 9;
38
39 /*
40 * Extract ECC requirements from 6th id byte.
41 * For Toshiba SLC, ecc requrements are as follows:
42 * - 43nm: 1 bit ECC for each 512Byte is required.
43 * - 32nm: 4 bit ECC for each 512Byte is required.
44 * - 24nm: 8 bit ECC for each 512Byte is required.
45 */
46 if (chip->id.len >= 6 && nand_is_slc(chip)) {
47 chip->ecc_step_ds = 512;
48 switch (chip->id.data[5] & 0x7) {
49 case 0x4:
50 chip->ecc_strength_ds = 1;
51 break;
52 case 0x5:
53 chip->ecc_strength_ds = 4;
54 break;
55 case 0x6:
56 chip->ecc_strength_ds = 8;
57 break;
58 default:
59 WARN(1, "Could not get ECC info");
60 chip->ecc_step_ds = 0;
61 break;
62 }
63 }
64 }
65
toshiba_nand_init(struct nand_chip * chip)66 static int toshiba_nand_init(struct nand_chip *chip)
67 {
68 if (nand_is_slc(chip))
69 chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
70
71 return 0;
72 }
73
74 const struct nand_manufacturer_ops toshiba_nand_manuf_ops = {
75 .detect = toshiba_nand_decode_id,
76 .init = toshiba_nand_init,
77 };
78
