Hi all On Fri, Nov 7, 2025 at 11:41 AM Eugen Hristev <[email protected]> wrote: > > > > On 11/6/25 19:01, Zixun LI wrote: > > This patch adds support for reading the unique ID from ONFI-compliant NAND > > flash devices. > > > > The unique ID is a 32 bytes long identifier that is useful for device > > identification and tracking. > > > > Tested on SAM9G25-EK with Macronix MX60LF8G18AC flash. > > > > Signed-off-by: Zixun LI <[email protected]> > > --- > > drivers/mtd/nand/raw/nand_base.c | 69 ++++++++++++++++++++++++++++++++ > > include/linux/mtd/rawnand.h | 8 ++++ > > 2 files changed, 77 insertions(+) > > > > diff --git a/drivers/mtd/nand/raw/nand_base.c > > b/drivers/mtd/nand/raw/nand_base.c > > index 48e3685d995..30aa578e074 100644 > > --- a/drivers/mtd/nand/raw/nand_base.c > > +++ b/drivers/mtd/nand/raw/nand_base.c > > @@ -991,6 +991,75 @@ static int nand_onfi_set_timings(struct mtd_info *mtd, > > struct nand_chip *chip) > > tmode_param); > > } > > > > +/** > > + * nand_onfi_read_unique_id - read the ONFI unique ID sequence > > + * @chip: NAND chip descriptor > > + * @buf: destination buffer > > + * @len: size of the destination buffer > > + * > > + * Issues the ONFI UNIQUE_ID command sequence, validates the unique ID and > > + * copies it into @buf. > > + * > > + * Return: 0 on success or negative error code otherwise. > > + */ > > +int nand_onfi_read_unique_id(struct nand_chip *chip, void *buf, > > + unsigned int len) > > +{ > > + struct mtd_info *mtd; > > + unsigned int copy; > > + unsigned int byte; > > + unsigned int copy_len; > > + u8 raw_id[ONFI_UNIQUE_ID_LEN * 2]; > > + u8 *out = buf; > > + int ret = -EIO; > > + > > + if (!chip) > > + return -EINVAL; > > + > > + if (len && !buf) > > + return -EINVAL; > > + > > + if (len > ONFI_UNIQUE_ID_LEN) > > + return -EINVAL; > > + > > + if (!chip->onfi_version) > > + return -EOPNOTSUPP; > > + > > + mtd = nand_to_mtd(chip); > > + nand_get_device(mtd, FL_READING); > > + chip->select_chip(mtd, 0); > > + > > + chip->cmdfunc(mtd, NAND_CMD_UNIQUE_ID, 0, -1); > > + > > + for (copy = 0; copy < ONFI_UNIQUE_ID_COPIES; copy++) { > > + for (byte = 0; byte < ONFI_UNIQUE_ID_LEN * 2; byte++) > > + raw_id[byte] = chip->read_byte(mtd); > > + > > + for (byte = 0; byte < ONFI_UNIQUE_ID_LEN; byte++) { > > + u8 lo = raw_id[byte]; > > + u8 hi = raw_id[byte + ONFI_UNIQUE_ID_LEN]; > > + > > + if ((lo ^ hi) != 0xff) > > + break; > > + } > > + > > + if (byte == ONFI_UNIQUE_ID_LEN) { > > + copy_len = min_t(unsigned int, len, > > ONFI_UNIQUE_ID_LEN); > > + > > + if (len) > > + memcpy(out, raw_id, copy_len); > > + > > + ret = 0; > > + goto out; > > + } > > + } > > + > > +out: > > + nand_release_device(mtd); > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(nand_onfi_read_unique_id); > > + > > /** > > * nand_setup_data_interface - Setup the best data interface and timings > > * @chip: The NAND chip > > diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h > > index 3e80b134063..87083c34aed 100644 > > --- a/include/linux/mtd/rawnand.h > > +++ b/include/linux/mtd/rawnand.h > > @@ -88,6 +88,7 @@ void nand_wait_ready(struct mtd_info *mtd); > > #define NAND_CMD_READID 0x90 > > #define NAND_CMD_ERASE2 0xd0 > > #define NAND_CMD_PARAM 0xec > > +#define NAND_CMD_UNIQUE_ID 0xed > > #define NAND_CMD_GET_FEATURES 0xee > > #define NAND_CMD_SET_FEATURES 0xef > > #define NAND_CMD_RESET 0xff > > @@ -409,6 +410,10 @@ struct onfi_ext_param_page { > > */ > > } __packed; > > > > +/* ONFI unique ID */ > > +#define ONFI_UNIQUE_ID_LEN 16 > > +#define ONFI_UNIQUE_ID_COPIES 16 > > + > > struct jedec_ecc_info { > > u8 ecc_bits; > > u8 codeword_size; > > @@ -1385,4 +1390,7 @@ int nand_write_data_op(struct nand_chip *chip, const > > void *buf, > > /* Default extended ID decoding function */ > > void nand_decode_ext_id(struct nand_chip *chip); > > > > +int nand_onfi_read_unique_id(struct nand_chip *chip, void *buf, > > + unsigned int len); > > + > > Something appears to be missing. Where is this function called ? >
I prefer to apply if we have a use case and a consumer of this patch. Michael > Eugen> #endif /* __LINUX_MTD_RAWNAND_H */ > -- Michael Nazzareno Trimarchi Co-Founder & Chief Executive Officer M. +39 347 913 2170 [email protected] __________________________________ Amarula Solutions BV Joop Geesinkweg 125, 1114 AB, Amsterdam, NL T. +31 (0)85 111 9172 [email protected] www.amarulasolutions.com
