1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2017 Free Electrons 4 * Copyright (C) 2017 NextThing Co 5 * 6 * Author: Boris Brezillon <boris.brezillon@free-electrons.com> 7 */ 8 9 #include "internals.h" 10 11 /* Bit for detecting BENAND */ 12 #define TOSHIBA_NAND_ID4_IS_BENAND BIT(7) 13 14 /* Recommended to rewrite for BENAND */ 15 #define TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED BIT(3) 16 17 static int toshiba_nand_benand_eccstatus(struct nand_chip *chip) 18 { 19 struct mtd_info *mtd = nand_to_mtd(chip); 20 int ret; 21 unsigned int max_bitflips = 0; 22 u8 status; 23 24 /* Check Status */ 25 ret = nand_status_op(chip, &status); 26 if (ret) 27 return ret; 28 29 if (status & NAND_STATUS_FAIL) { 30 /* uncorrected */ 31 mtd->ecc_stats.failed++; 32 } else if (status & TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED) { 33 /* corrected */ 34 max_bitflips = mtd->bitflip_threshold; 35 mtd->ecc_stats.corrected += max_bitflips; 36 } 37 38 return max_bitflips; 39 } 40 41 static int 42 toshiba_nand_read_page_benand(struct nand_chip *chip, uint8_t *buf, 43 int oob_required, int page) 44 { 45 int ret; 46 47 ret = nand_read_page_raw(chip, buf, oob_required, page); 48 if (ret) 49 return ret; 50 51 return toshiba_nand_benand_eccstatus(chip); 52 } 53 54 static int 55 toshiba_nand_read_subpage_benand(struct nand_chip *chip, uint32_t data_offs, 56 uint32_t readlen, uint8_t *bufpoi, int page) 57 { 58 int ret; 59 60 ret = nand_read_page_op(chip, page, data_offs, 61 bufpoi + data_offs, readlen); 62 if (ret) 63 return ret; 64 65 return toshiba_nand_benand_eccstatus(chip); 66 } 67 68 static void toshiba_nand_benand_init(struct nand_chip *chip) 69 { 70 struct mtd_info *mtd = nand_to_mtd(chip); 71 72 /* 73 * On BENAND, the entire OOB region can be used by the MTD user. 74 * The calculated ECC bytes are stored into other isolated 75 * area which is not accessible to users. 76 * This is why chip->ecc.bytes = 0. 77 */ 78 chip->ecc.bytes = 0; 79 chip->ecc.size = 512; 80 chip->ecc.strength = 8; 81 chip->ecc.read_page = toshiba_nand_read_page_benand; 82 chip->ecc.read_subpage = toshiba_nand_read_subpage_benand; 83 chip->ecc.write_page = nand_write_page_raw; 84 chip->ecc.read_page_raw = nand_read_page_raw_notsupp; 85 chip->ecc.write_page_raw = nand_write_page_raw_notsupp; 86 87 chip->options |= NAND_SUBPAGE_READ; 88 89 mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops); 90 } 91 92 static void toshiba_nand_decode_id(struct nand_chip *chip) 93 { 94 struct mtd_info *mtd = nand_to_mtd(chip); 95 struct nand_memory_organization *memorg; 96 97 memorg = nanddev_get_memorg(&chip->base); 98 99 nand_decode_ext_id(chip); 100 101 /* 102 * Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per 103 * 512B page. For Toshiba SLC, we decode the 5th/6th byte as 104 * follows: 105 * - ID byte 6, bits[2:0]: 100b -> 43nm, 101b -> 32nm, 106 * 110b -> 24nm 107 * - ID byte 5, bit[7]: 1 -> BENAND, 0 -> raw SLC 108 */ 109 if (chip->id.len >= 6 && nand_is_slc(chip) && 110 (chip->id.data[5] & 0x7) == 0x6 /* 24nm */ && 111 !(chip->id.data[4] & 0x80) /* !BENAND */) { 112 memorg->oobsize = 32 * memorg->pagesize >> 9; 113 mtd->oobsize = memorg->oobsize; 114 } 115 116 /* 117 * Extract ECC requirements from 6th id byte. 118 * For Toshiba SLC, ecc requrements are as follows: 119 * - 43nm: 1 bit ECC for each 512Byte is required. 120 * - 32nm: 4 bit ECC for each 512Byte is required. 121 * - 24nm: 8 bit ECC for each 512Byte is required. 122 */ 123 if (chip->id.len >= 6 && nand_is_slc(chip)) { 124 chip->base.eccreq.step_size = 512; 125 switch (chip->id.data[5] & 0x7) { 126 case 0x4: 127 chip->base.eccreq.strength = 1; 128 break; 129 case 0x5: 130 chip->base.eccreq.strength = 4; 131 break; 132 case 0x6: 133 chip->base.eccreq.strength = 8; 134 break; 135 default: 136 WARN(1, "Could not get ECC info"); 137 chip->base.eccreq.step_size = 0; 138 break; 139 } 140 } 141 } 142 143 static int toshiba_nand_init(struct nand_chip *chip) 144 { 145 if (nand_is_slc(chip)) 146 chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE; 147 148 /* Check that chip is BENAND and ECC mode is on-die */ 149 if (nand_is_slc(chip) && chip->ecc.mode == NAND_ECC_ON_DIE && 150 chip->id.data[4] & TOSHIBA_NAND_ID4_IS_BENAND) 151 toshiba_nand_benand_init(chip); 152 153 return 0; 154 } 155 156 const struct nand_manufacturer_ops toshiba_nand_manuf_ops = { 157 .detect = toshiba_nand_decode_id, 158 .init = toshiba_nand_init, 159 }; 160