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 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 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