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 /* ECC Status Read Command for BENAND */ 18 #define TOSHIBA_NAND_CMD_ECC_STATUS_READ 0x7A 19 20 /* ECC Status Mask for BENAND */ 21 #define TOSHIBA_NAND_ECC_STATUS_MASK 0x0F 22 23 /* Uncorrectable Error for BENAND */ 24 #define TOSHIBA_NAND_ECC_STATUS_UNCORR 0x0F 25 26 /* Max ECC Steps for BENAND */ 27 #define TOSHIBA_NAND_MAX_ECC_STEPS 8 28 29 static int toshiba_nand_benand_read_eccstatus_op(struct nand_chip *chip, 30 u8 *buf) 31 { 32 u8 *ecc_status = buf; 33 34 if (nand_has_exec_op(chip)) { 35 const struct nand_sdr_timings *sdr = 36 nand_get_sdr_timings(&chip->data_interface); 37 struct nand_op_instr instrs[] = { 38 NAND_OP_CMD(TOSHIBA_NAND_CMD_ECC_STATUS_READ, 39 PSEC_TO_NSEC(sdr->tADL_min)), 40 NAND_OP_8BIT_DATA_IN(chip->ecc.steps, ecc_status, 0), 41 }; 42 struct nand_operation op = NAND_OPERATION(chip->cur_cs, instrs); 43 44 return nand_exec_op(chip, &op); 45 } 46 47 return -ENOTSUPP; 48 } 49 50 static int toshiba_nand_benand_eccstatus(struct nand_chip *chip) 51 { 52 struct mtd_info *mtd = nand_to_mtd(chip); 53 int ret; 54 unsigned int max_bitflips = 0; 55 u8 status, ecc_status[TOSHIBA_NAND_MAX_ECC_STEPS]; 56 57 /* Check Status */ 58 ret = toshiba_nand_benand_read_eccstatus_op(chip, ecc_status); 59 if (!ret) { 60 unsigned int i, bitflips = 0; 61 62 for (i = 0; i < chip->ecc.steps; i++) { 63 bitflips = ecc_status[i] & TOSHIBA_NAND_ECC_STATUS_MASK; 64 if (bitflips == TOSHIBA_NAND_ECC_STATUS_UNCORR) { 65 mtd->ecc_stats.failed++; 66 } else { 67 mtd->ecc_stats.corrected += bitflips; 68 max_bitflips = max(max_bitflips, bitflips); 69 } 70 } 71 72 return max_bitflips; 73 } 74 75 /* 76 * Fallback to regular status check if 77 * toshiba_nand_benand_read_eccstatus_op() failed. 78 */ 79 ret = nand_status_op(chip, &status); 80 if (ret) 81 return ret; 82 83 if (status & NAND_STATUS_FAIL) { 84 /* uncorrected */ 85 mtd->ecc_stats.failed++; 86 } else if (status & TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED) { 87 /* corrected */ 88 max_bitflips = mtd->bitflip_threshold; 89 mtd->ecc_stats.corrected += max_bitflips; 90 } 91 92 return max_bitflips; 93 } 94 95 static int 96 toshiba_nand_read_page_benand(struct nand_chip *chip, uint8_t *buf, 97 int oob_required, int page) 98 { 99 int ret; 100 101 ret = nand_read_page_raw(chip, buf, oob_required, page); 102 if (ret) 103 return ret; 104 105 return toshiba_nand_benand_eccstatus(chip); 106 } 107 108 static int 109 toshiba_nand_read_subpage_benand(struct nand_chip *chip, uint32_t data_offs, 110 uint32_t readlen, uint8_t *bufpoi, int page) 111 { 112 int ret; 113 114 ret = nand_read_page_op(chip, page, data_offs, 115 bufpoi + data_offs, readlen); 116 if (ret) 117 return ret; 118 119 return toshiba_nand_benand_eccstatus(chip); 120 } 121 122 static void toshiba_nand_benand_init(struct nand_chip *chip) 123 { 124 struct mtd_info *mtd = nand_to_mtd(chip); 125 126 /* 127 * On BENAND, the entire OOB region can be used by the MTD user. 128 * The calculated ECC bytes are stored into other isolated 129 * area which is not accessible to users. 130 * This is why chip->ecc.bytes = 0. 131 */ 132 chip->ecc.bytes = 0; 133 chip->ecc.size = 512; 134 chip->ecc.strength = 8; 135 chip->ecc.read_page = toshiba_nand_read_page_benand; 136 chip->ecc.read_subpage = toshiba_nand_read_subpage_benand; 137 chip->ecc.write_page = nand_write_page_raw; 138 chip->ecc.read_page_raw = nand_read_page_raw_notsupp; 139 chip->ecc.write_page_raw = nand_write_page_raw_notsupp; 140 141 chip->options |= NAND_SUBPAGE_READ; 142 143 mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops); 144 } 145 146 static void toshiba_nand_decode_id(struct nand_chip *chip) 147 { 148 struct mtd_info *mtd = nand_to_mtd(chip); 149 struct nand_memory_organization *memorg; 150 151 memorg = nanddev_get_memorg(&chip->base); 152 153 nand_decode_ext_id(chip); 154 155 /* 156 * Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per 157 * 512B page. For Toshiba SLC, we decode the 5th/6th byte as 158 * follows: 159 * - ID byte 6, bits[2:0]: 100b -> 43nm, 101b -> 32nm, 160 * 110b -> 24nm 161 * - ID byte 5, bit[7]: 1 -> BENAND, 0 -> raw SLC 162 */ 163 if (chip->id.len >= 6 && nand_is_slc(chip) && 164 (chip->id.data[5] & 0x7) == 0x6 /* 24nm */ && 165 !(chip->id.data[4] & TOSHIBA_NAND_ID4_IS_BENAND) /* !BENAND */) { 166 memorg->oobsize = 32 * memorg->pagesize >> 9; 167 mtd->oobsize = memorg->oobsize; 168 } 169 170 /* 171 * Extract ECC requirements from 6th id byte. 172 * For Toshiba SLC, ecc requrements are as follows: 173 * - 43nm: 1 bit ECC for each 512Byte is required. 174 * - 32nm: 4 bit ECC for each 512Byte is required. 175 * - 24nm: 8 bit ECC for each 512Byte is required. 176 */ 177 if (chip->id.len >= 6 && nand_is_slc(chip)) { 178 chip->base.eccreq.step_size = 512; 179 switch (chip->id.data[5] & 0x7) { 180 case 0x4: 181 chip->base.eccreq.strength = 1; 182 break; 183 case 0x5: 184 chip->base.eccreq.strength = 4; 185 break; 186 case 0x6: 187 chip->base.eccreq.strength = 8; 188 break; 189 default: 190 WARN(1, "Could not get ECC info"); 191 chip->base.eccreq.step_size = 0; 192 break; 193 } 194 } 195 } 196 197 static int toshiba_nand_init(struct nand_chip *chip) 198 { 199 if (nand_is_slc(chip)) 200 chip->options |= NAND_BBM_FIRSTPAGE | NAND_BBM_SECONDPAGE; 201 202 /* Check that chip is BENAND and ECC mode is on-die */ 203 if (nand_is_slc(chip) && chip->ecc.mode == NAND_ECC_ON_DIE && 204 chip->id.data[4] & TOSHIBA_NAND_ID4_IS_BENAND) 205 toshiba_nand_benand_init(chip); 206 207 return 0; 208 } 209 210 const struct nand_manufacturer_ops toshiba_nand_manuf_ops = { 211 .detect = toshiba_nand_decode_id, 212 .init = toshiba_nand_init, 213 }; 214