linux_dsm_epyc7002/drivers/mtd/nand/raw/nand_esmt.c
Marcel Ziswiler a68642adbb mtd: rawnand: ESMT: retrieve ECC requirements from 5th id byte
This patch enables support to read the ECC level from the NAND flash
using ESMT SLC NAND ID byte 5 information as documented e.g. in the
following data sheet:

https://www.esmt.com.tw/upload/pdf/ESMT/datasheets/F59L1G81LA(2Y).pdf

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
2018-10-03 11:12:25 +02:00

48 lines
944 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018 Toradex AG
*
* Author: Marcel Ziswiler <marcel.ziswiler@toradex.com>
*/
#include <linux/mtd/rawnand.h>
#include "internals.h"
static void esmt_nand_decode_id(struct nand_chip *chip)
{
nand_decode_ext_id(chip);
/* Extract ECC requirements from 5th id byte. */
if (chip->id.len >= 5 && nand_is_slc(chip)) {
chip->ecc_step_ds = 512;
switch (chip->id.data[4] & 0x3) {
case 0x0:
chip->ecc_strength_ds = 4;
break;
case 0x1:
chip->ecc_strength_ds = 2;
break;
case 0x2:
chip->ecc_strength_ds = 1;
break;
default:
WARN(1, "Could not get ECC info");
chip->ecc_step_ds = 0;
break;
}
}
}
static int esmt_nand_init(struct nand_chip *chip)
{
if (nand_is_slc(chip))
chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
return 0;
}
const struct nand_manufacturer_ops esmt_nand_manuf_ops = {
.detect = esmt_nand_decode_id,
.init = esmt_nand_init,
};