RE: [EXT] Re: [PATCH 2/8] mtd: nand: move support functions for ONFI to nand/onfi.c

From: Shivamurthy Shastri (sshivamurthy)
Date: Mon Aug 19 2019 - 04:36:20 EST


Hi Miquel,

>
> Hi shiva.linuxworks@xxxxxxxxx,
>
> shiva.linuxworks@xxxxxxxxx wrote on Mon, 22 Jul 2019 07:56:15 +0200:
>
> > From: Shivamurthy Shastri <sshivamurthy@xxxxxxxxxx>
>
> "mtd: nand: move ONFI specific helpers to nand/onfi.c"?

I will use this.

>
> >
> > These functions are support functions for enabling ONFI standard and
> > common between raw NAND and SPI NAND.
>
> "
> These are ONFI specific helpers that might be shared between raw and
> SPI NAND logics, move them to a generic place.
>
> While at it, add kernel doc on the function parameters.
> "
>

I will use this.

> >
> > Signed-off-by: Shivamurthy Shastri <sshivamurthy@xxxxxxxxxx>
> > ---
> > drivers/mtd/nand/Makefile | 2 +-
> > drivers/mtd/nand/onfi.c | 89
> ++++++++++++++++++++++++++++++++
> > drivers/mtd/nand/raw/nand_base.c | 18 -------
> > drivers/mtd/nand/raw/nand_onfi.c | 43 ---------------
> > 4 files changed, 90 insertions(+), 62 deletions(-)
> > create mode 100644 drivers/mtd/nand/onfi.c
> >
> > diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
> > index 7ecd80c0a66e..221945c223c3 100644
> > --- a/drivers/mtd/nand/Makefile
> > +++ b/drivers/mtd/nand/Makefile
> > @@ -1,6 +1,6 @@
> > # SPDX-License-Identifier: GPL-2.0
> >
> > -nandcore-objs := core.o bbt.o
> > +nandcore-objs := core.o bbt.o onfi.o
> > obj-$(CONFIG_MTD_NAND_CORE) += nandcore.o
> >
> > obj-y += onenand/
> > diff --git a/drivers/mtd/nand/onfi.c b/drivers/mtd/nand/onfi.c
> > new file mode 100644
> > index 000000000000..7aaf36dfc5e0
> > --- /dev/null
> > +++ b/drivers/mtd/nand/onfi.c
> > @@ -0,0 +1,89 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +#define pr_fmt(fmt) "nand-onfi: " fmt
> > +
> > +#include <linux/mtd/onfi.h>
> > +#include <linux/mtd/nand.h>
> > +
> > +/**
> > + * onfi_crc16() - Check CRC of ONFI table
>
> There is no check in this function.
>
> Derive the CRC of an ONFI table

okay.

>
> > + * @crc: base CRC
> > + * @p: buffer pointing to ONFI table
> ^ the
> > + * @len: length of ONFI table
> ^the
> > + *
> > + * Return: CRC of the ONFI table
> @return: the CRC of the given ONFI table
>
> > + */
> > +u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
> > +{
> > + int i;
> > +
> > + while (len--) {
> > + crc ^= *p++ << 8;
> > + for (i = 0; i < 8; i++)
> > + crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
> > + }
> > +
> > + return crc;
> > +}
> > +EXPORT_SYMBOL_GPL(onfi_crc16);
> > +
> > +/**
> > + * nand_bit_wise_majority() - Recover data with bit-wise majority
> > + * @srcbufs: buffer pointing to ONFI table
> > + * @nsrcbufs: length of ONFI table
> ^the
> > + * @dstbuf: valid ONFI table to be returned
> > + * @bufsize: length og valid ONFI table
> of the valid...
> > + *
>
> Extra line
>
> > + */
> > +void nand_bit_wise_majority(const void **srcbufs,
> > + unsigned int nsrcbufs,
> > + void *dstbuf,
> > + unsigned int bufsize)
> > +{
> > + int i, j, k;
> > +
> > + for (i = 0; i < bufsize; i++) {
> > + u8 val = 0;
> > +
> > + for (j = 0; j < 8; j++) {
> > + unsigned int cnt = 0;
> > +
> > + for (k = 0; k < nsrcbufs; k++) {
> > + const u8 *srcbuf = srcbufs[k];
> > +
> > + if (srcbuf[i] & BIT(j))
> > + cnt++;
> > + }
> > +
> > + if (cnt > nsrcbufs / 2)
> > + val |= BIT(j);
> > + }
> > +
> > + ((u8 *)dstbuf)[i] = val;
> > + }
> > +}
> > +EXPORT_SYMBOL_GPL(nand_bit_wise_majority);
> > +
> > +/**
> > + * sanitize_string() - Sanitize ONFI strings so we can safely print them
>
> It is used by JEDEC logic so this should be moved elsewhere and not
> refer to any ONFI naming.

okay, I will move this.

>
> > + * @s: string to be sanitized
> > + * @len: length of the string
> > + *
> > + */
> > +void sanitize_string(u8 *s, size_t len)
> > +{
> > + ssize_t i;
> > +
> > + /* Null terminate */
> > + s[len - 1] = 0;
> > +
> > + /* Remove non printable chars */
> > + for (i = 0; i < len - 1; i++) {
> > + if (s[i] < ' ' || s[i] > 127)
> > + s[i] = '?';
> > + }
> > +
> > + /* Remove trailing spaces */
> > + strim(s);
> > +}
> > +EXPORT_SYMBOL_GPL(sanitize_string);
> > diff --git a/drivers/mtd/nand/raw/nand_base.c
> b/drivers/mtd/nand/raw/nand_base.c
> > index 6ecd1c496ce3..c198829bcd79 100644
> > --- a/drivers/mtd/nand/raw/nand_base.c
> > +++ b/drivers/mtd/nand/raw/nand_base.c
> > @@ -4375,24 +4375,6 @@ static void nand_set_defaults(struct nand_chip
> *chip)
> > chip->buf_align = 1;
> > }
> >
> > -/* Sanitize ONFI strings so we can safely print them */
> > -void sanitize_string(uint8_t *s, size_t len)
> > -{
> > - ssize_t i;
> > -
> > - /* Null terminate */
> > - s[len - 1] = 0;
> > -
> > - /* Remove non printable chars */
> > - for (i = 0; i < len - 1; i++) {
> > - if (s[i] < ' ' || s[i] > 127)
> > - s[i] = '?';
> > - }
> > -
> > - /* Remove trailing spaces */
> > - strim(s);
> > -}
> > -
> > /*
> > * nand_id_has_period - Check if an ID string has a given wraparound
> period
> > * @id_data: the ID string
> > diff --git a/drivers/mtd/nand/raw/nand_onfi.c
> b/drivers/mtd/nand/raw/nand_onfi.c
> > index 0b879bd0a68c..2e8edfa636ef 100644
> > --- a/drivers/mtd/nand/raw/nand_onfi.c
> > +++ b/drivers/mtd/nand/raw/nand_onfi.c
> > @@ -16,18 +16,6 @@
> >
> > #include "internals.h"
> >
> > -u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
> > -{
> > - int i;
> > - while (len--) {
> > - crc ^= *p++ << 8;
> > - for (i = 0; i < 8; i++)
> > - crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
> > - }
> > -
> > - return crc;
> > -}
> > -
> > /* Parse the Extended Parameter Page. */
> > static int nand_flash_detect_ext_param_page(struct nand_chip *chip,
> > struct nand_onfi_params *p)
> > @@ -103,37 +91,6 @@ static int
> nand_flash_detect_ext_param_page(struct nand_chip *chip,
> > return ret;
> > }
> >
> > -/*
> > - * Recover data with bit-wise majority
> > - */
> > -static void nand_bit_wise_majority(const void **srcbufs,
> > - unsigned int nsrcbufs,
> > - void *dstbuf,
> > - unsigned int bufsize)
> > -{
> > - int i, j, k;
> > -
> > - for (i = 0; i < bufsize; i++) {
> > - u8 val = 0;
> > -
> > - for (j = 0; j < 8; j++) {
> > - unsigned int cnt = 0;
> > -
> > - for (k = 0; k < nsrcbufs; k++) {
> > - const u8 *srcbuf = srcbufs[k];
> > -
> > - if (srcbuf[i] & BIT(j))
> > - cnt++;
> > - }
> > -
> > - if (cnt > nsrcbufs / 2)
> > - val |= BIT(j);
> > - }
> > -
> > - ((u8 *)dstbuf)[i] = val;
> > - }
> > -}
> > -
> > /*
> > * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
> > */
>
> Thanks,
> MiquÃl

Thanks,
Shiva