diff options
author | Michael Walle <michael@walle.cc> | 2021-06-07 13:27:44 +0200 |
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committer | Vignesh Raghavendra <vigneshr@ti.com> | 2021-06-09 23:34:16 +0530 |
commit | c6ec3e1e3a853f9469c7d07b0fde0be4da8c3ba1 (patch) | |
tree | 89036d0244d186aa59bd25578ca20befb1084e9c /drivers/mtd/spi-nor/otp.c | |
parent | 388161ca45c911f566b71716bce5ff0119fb5522 (diff) | |
download | linux-c6ec3e1e3a853f9469c7d07b0fde0be4da8c3ba1.tar.bz2 |
mtd: spi-nor: otp: implement erase for Winbond and similar flashes
Winbond flashes with OTP support provide a command to erase the OTP
data. This might come in handy during development.
This was tested with a Winbond W25Q32JW on a LS1028A SoC with the
NXP FSPI controller.
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Diffstat (limited to 'drivers/mtd/spi-nor/otp.c')
-rw-r--r-- | drivers/mtd/spi-nor/otp.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/otp.c b/drivers/mtd/spi-nor/otp.c index 89fe52e3851a..983e40b19134 100644 --- a/drivers/mtd/spi-nor/otp.c +++ b/drivers/mtd/spi-nor/otp.c @@ -120,6 +120,38 @@ out: return ret ?: written; } +/** + * spi_nor_otp_erase_secr() - erase a security register + * @nor: pointer to 'struct spi_nor' + * @addr: offset of the security register to be erased + * + * Erase a security register by using the SPINOR_OP_ESECR command. + * + * For more information on the term "security register", see the documentation + * of spi_nor_otp_read_secr(). + * + * This method is used on GigaDevice and Winbond flashes. + * + * Return: 0 on success, -errno otherwise + */ +int spi_nor_otp_erase_secr(struct spi_nor *nor, loff_t addr) +{ + u8 erase_opcode = nor->erase_opcode; + int ret; + + ret = spi_nor_write_enable(nor); + if (ret) + return ret; + + nor->erase_opcode = SPINOR_OP_ESECR; + ret = spi_nor_erase_sector(nor, addr); + nor->erase_opcode = erase_opcode; + if (ret) + return ret; + + return spi_nor_wait_till_ready(nor); +} + static int spi_nor_otp_lock_bit_cr(unsigned int region) { static const int lock_bits[] = { SR2_LB1, SR2_LB2, SR2_LB3 }; @@ -360,6 +392,59 @@ static int spi_nor_mtd_otp_write(struct mtd_info *mtd, loff_t to, size_t len, return spi_nor_mtd_otp_read_write(mtd, to, len, retlen, buf, true); } +static int spi_nor_mtd_otp_erase(struct mtd_info *mtd, loff_t from, size_t len) +{ + struct spi_nor *nor = mtd_to_spi_nor(mtd); + const struct spi_nor_otp_ops *ops = nor->params->otp.ops; + const size_t rlen = spi_nor_otp_region_len(nor); + unsigned int region; + loff_t rstart; + int ret; + + /* OTP erase is optional */ + if (!ops->erase) + return -EOPNOTSUPP; + + if (!len) + return 0; + + if (from < 0 || (from + len) > spi_nor_otp_size(nor)) + return -EINVAL; + + /* the user has to explicitly ask for whole regions */ + if (!IS_ALIGNED(len, rlen) || !IS_ALIGNED(from, rlen)) + return -EINVAL; + + ret = spi_nor_lock_and_prep(nor); + if (ret) + return ret; + + ret = spi_nor_mtd_otp_range_is_locked(nor, from, len); + if (ret < 0) { + goto out; + } else if (ret) { + ret = -EROFS; + goto out; + } + + while (len) { + region = spi_nor_otp_offset_to_region(nor, from); + rstart = spi_nor_otp_region_start(nor, region); + + ret = ops->erase(nor, rstart); + if (ret) + goto out; + + len -= rlen; + from += rlen; + } + +out: + spi_nor_unlock_and_unprep(nor); + + return ret; +} + static int spi_nor_mtd_otp_lock(struct mtd_info *mtd, loff_t from, size_t len) { struct spi_nor *nor = mtd_to_spi_nor(mtd); @@ -418,4 +503,5 @@ void spi_nor_otp_init(struct spi_nor *nor) mtd->_read_user_prot_reg = spi_nor_mtd_otp_read; mtd->_write_user_prot_reg = spi_nor_mtd_otp_write; mtd->_lock_user_prot_reg = spi_nor_mtd_otp_lock; + mtd->_erase_user_prot_reg = spi_nor_mtd_otp_erase; } |