diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile index da05b03f28d2..136f245c91dc 100644 --- a/drivers/mtd/spi-nor/Makefile +++ b/drivers/mtd/spi-nor/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 -spi-nor-objs := core.o sfdp.o swp.o +spi-nor-objs := core.o sfdp.o swp.o otp.o spi-nor-objs += atmel.o spi-nor-objs += catalyst.o spi-nor-objs += eon.o diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 5bc7ecfe7740..9e27ea727628 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -2548,6 +2548,8 @@ static void spi_nor_info_init_params(struct spi_nor *nor) params->quad_enable = spi_nor_sr2_bit1_quad_enable; params->set_4byte_addr_mode = spansion_set_4byte_addr_mode; params->setup = spi_nor_default_setup; + params->otp.org = &info->otp_org; + /* Default to 16-bit Write Status (01h) Command */ nor->flags |= SNOR_F_HAS_16BIT_SR; @@ -3156,6 +3158,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, if (ret) return ret; + /* Configure OTP parameters and ops */ + spi_nor_otp_init(nor); + dev_info(dev, "%s (%lld Kbytes)\n", info->name, (long long)mtd->size >> 10); diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index 74f6026b7335..cfbc43c5cc57 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -187,6 +187,45 @@ struct spi_nor_locking_ops { int (*is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len); }; +/** + * struct spi_nor_otp_organization - Structure to describe the SPI NOR OTP regions + * @len: size of one OTP region in bytes. + * @base: start address of the OTP area. + * @offset: offset between consecutive OTP regions if there are more + * than one. + * @n_regions: number of individual OTP regions. + */ +struct spi_nor_otp_organization { + size_t len; + loff_t base; + loff_t offset; + unsigned int n_regions; +}; + +/** + * struct spi_nor_otp_ops - SPI NOR OTP methods + * @read: read from the SPI NOR OTP area. + * @write: write to the SPI NOR OTP area. + * @lock: lock an OTP region. + * @is_locked: check if an OTP region of the SPI NOR is locked. + */ +struct spi_nor_otp_ops { + int (*read)(struct spi_nor *nor, loff_t addr, size_t len, u8 *buf); + int (*write)(struct spi_nor *nor, loff_t addr, size_t len, u8 *buf); + int (*lock)(struct spi_nor *nor, unsigned int region); + int (*is_locked)(struct spi_nor *nor, unsigned int region); +}; + +/** + * struct spi_nor_otp - SPI NOR OTP grouping structure + * @org: OTP region organization + * @ops: OTP access ops + */ +struct spi_nor_otp { + const struct spi_nor_otp_organization *org; + const struct spi_nor_otp_ops *ops; +}; + /** * struct spi_nor_flash_parameter - SPI NOR flash parameters and settings. * Includes legacy flash parameters and settings that can be overwritten @@ -208,6 +247,7 @@ struct spi_nor_locking_ops { * higher index in the array, the higher priority. * @erase_map: the erase map parsed from the SFDP Sector Map Parameter * Table. + * @otp_info: describes the OTP regions. * @octal_dtr_enable: enables SPI NOR octal DTR mode. * @quad_enable: enables SPI NOR quad mode. * @set_4byte_addr_mode: puts the SPI NOR in 4 byte addressing mode. @@ -219,6 +259,7 @@ struct spi_nor_locking_ops { * e.g. different opcodes, specific address calculation, * page size, etc. * @locking_ops: SPI NOR locking methods. + * @otp: SPI NOR OTP methods. */ struct spi_nor_flash_parameter { u64 size; @@ -232,6 +273,7 @@ struct spi_nor_flash_parameter { struct spi_nor_pp_command page_programs[SNOR_CMD_PP_MAX]; struct spi_nor_erase_map erase_map; + struct spi_nor_otp otp; int (*octal_dtr_enable)(struct spi_nor *nor, bool enable); int (*quad_enable)(struct spi_nor *nor); @@ -338,6 +380,8 @@ struct flash_info { * power-up in a write-protected state. */ + const struct spi_nor_otp_organization otp_org; + /* Part specific fixup hooks. */ const struct spi_nor_fixups *fixups; }; @@ -392,6 +436,14 @@ struct flash_info { .addr_width = 3, \ .flags = SPI_NOR_NO_FR | SPI_NOR_XSR_RDY, +#define OTP_INFO(_len, _n_regions, _base, _offset) \ + .otp_org = { \ + .len = (_len), \ + .base = (_base), \ + .offset = (_offset), \ + .n_regions = (_n_regions), \ + }, + /** * struct spi_nor_manufacturer - SPI NOR manufacturer object * @name: manufacturer name @@ -474,6 +526,7 @@ int spi_nor_post_bfpt_fixups(struct spi_nor *nor, void spi_nor_init_default_locking_ops(struct spi_nor *nor); void spi_nor_try_unlock_all(struct spi_nor *nor); void spi_nor_register_locking_ops(struct spi_nor *nor); +void spi_nor_otp_init(struct spi_nor *nor); static struct spi_nor __maybe_unused *mtd_to_spi_nor(struct mtd_info *mtd) { diff --git a/drivers/mtd/spi-nor/otp.c b/drivers/mtd/spi-nor/otp.c new file mode 100644 index 000000000000..075b7290a95d --- /dev/null +++ b/drivers/mtd/spi-nor/otp.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * OTP support for SPI NOR flashes + * + * Copyright (C) 2021 Michael Walle + */ + +#include +#include +#include + +#include "core.h" + +#define spi_nor_otp_region_len(nor) ((nor)->params->otp.org->len) +#define spi_nor_otp_n_regions(nor) ((nor)->params->otp.org->n_regions) + +static loff_t spi_nor_otp_region_start(const struct spi_nor *nor, unsigned int region) +{ + const struct spi_nor_otp_organization *org = nor->params->otp.org; + + return org->base + region * org->offset; +} + +static size_t spi_nor_otp_size(struct spi_nor *nor) +{ + return spi_nor_otp_n_regions(nor) * spi_nor_otp_region_len(nor); +} + +/* Translate the file offsets from and to OTP regions. */ +static loff_t spi_nor_otp_region_to_offset(struct spi_nor *nor, unsigned int region) +{ + return region * spi_nor_otp_region_len(nor); +} + +static unsigned int spi_nor_otp_offset_to_region(struct spi_nor *nor, loff_t ofs) +{ + return div64_u64(ofs, spi_nor_otp_region_len(nor)); +} + +static int spi_nor_mtd_otp_info(struct mtd_info *mtd, size_t len, + size_t *retlen, struct otp_info *buf) +{ + struct spi_nor *nor = mtd_to_spi_nor(mtd); + const struct spi_nor_otp_ops *ops = nor->params->otp.ops; + unsigned int n_regions = spi_nor_otp_n_regions(nor); + unsigned int i; + int ret, locked; + + if (len < n_regions * sizeof(*buf)) + return -ENOSPC; + + ret = spi_nor_lock_and_prep(nor); + if (ret) + return ret; + + for (i = 0; i < n_regions; i++) { + buf->start = spi_nor_otp_region_to_offset(nor, i); + buf->length = spi_nor_otp_region_len(nor); + + locked = ops->is_locked(nor, i); + if (locked < 0) { + ret = locked; + goto out; + } + + buf->locked = !!locked; + buf++; + } + + *retlen = n_regions * sizeof(*buf); + +out: + spi_nor_unlock_and_unprep(nor); + + return ret; +} + +static int spi_nor_mtd_otp_read_write(struct mtd_info *mtd, loff_t ofs, + size_t total_len, size_t *retlen, + u8 *buf, bool is_write) +{ + 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); + loff_t rstart, rofs; + unsigned int region; + size_t len; + int ret; + + if (ofs < 0 || ofs >= spi_nor_otp_size(nor)) + return 0; + + ret = spi_nor_lock_and_prep(nor); + if (ret) + return ret; + + /* don't access beyond the end */ + total_len = min_t(size_t, total_len, spi_nor_otp_size(nor) - ofs); + + *retlen = 0; + while (total_len) { + /* + * The OTP regions are mapped into a contiguous area starting + * at 0 as expected by the MTD layer. This will map the MTD + * file offsets to the address of an OTP region as used in the + * actual SPI commands. + */ + region = spi_nor_otp_offset_to_region(nor, ofs); + rstart = spi_nor_otp_region_start(nor, region); + + /* + * The size of a OTP region is expected to be a power of two, + * thus we can just mask the lower bits and get the offset into + * a region. + */ + rofs = ofs & (rlen - 1); + + /* don't access beyond one OTP region */ + len = min_t(size_t, total_len, rlen - rofs); + + if (is_write) + ret = ops->write(nor, rstart + rofs, len, buf); + else + ret = ops->read(nor, rstart + rofs, len, buf); + if (ret == 0) + ret = -EIO; + if (ret < 0) + goto out; + + *retlen += ret; + ofs += ret; + buf += ret; + total_len -= ret; + } + ret = 0; + +out: + spi_nor_unlock_and_unprep(nor); + return ret; +} + +static int spi_nor_mtd_otp_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u8 *buf) +{ + return spi_nor_mtd_otp_read_write(mtd, from, len, retlen, buf, false); +} + +static int spi_nor_mtd_otp_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, u8 *buf) +{ + return spi_nor_mtd_otp_read_write(mtd, to, len, retlen, buf, true); +} + +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); + const struct spi_nor_otp_ops *ops = nor->params->otp.ops; + const size_t rlen = spi_nor_otp_region_len(nor); + unsigned int region; + int ret; + + 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; + + while (len) { + region = spi_nor_otp_offset_to_region(nor, from); + ret = ops->lock(nor, region); + if (ret) + goto out; + + len -= rlen; + from += rlen; + } + +out: + spi_nor_unlock_and_unprep(nor); + + return ret; +} + +void spi_nor_otp_init(struct spi_nor *nor) +{ + struct mtd_info *mtd = &nor->mtd; + + if (!nor->params->otp.ops) + return; + + if (WARN_ON(!is_power_of_2(spi_nor_otp_region_len(nor)))) + return; + + /* + * We only support user_prot callbacks (yet). + * + * Some SPI NOR flashes like Macronix ones can be ordered in two + * different variants. One with a factory locked OTP area and one where + * it is left to the user to write to it. The factory locked OTP is + * usually preprogrammed with an "electrical serial number". We don't + * support these for now. + */ + mtd->_get_user_prot_info = spi_nor_mtd_otp_info; + 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; +}