[PATCH 2/2] imx-bbu-nand-fcb: add support for imx6ul
Jan Remmet
J.Remmet at phytec.de
Thu Apr 27 02:40:44 PDT 2017
On Thu, Apr 27, 2017 at 09:01:32AM +0200, Sascha Hauer wrote:
> On Wed, Apr 26, 2017 at 04:43:16PM +0200, Jan Remmet wrote:
> > On Wed, Dec 14, 2016 at 08:59:08AM +0100, Jan Remmet wrote:
> > > imx6ul secure the fcb with bch 40. The imx-kobs tool use a own modified
> > > bch lib. They reverse the bit order of the data and the ecc.
> > > To use the bch lib in barebox the bytes in the data buffers must be
> > > reversed.
> > > The data layout on nand is bit aligned. But with 40 bits this is not an
> > > issue for imx6ul now.
> > I saw that this wasn't applied, is there any rework needed?
>
> It seems this patch slipped through the cracks. Applied now.
Thanks
Jan
>
> Sascha
>
> >
> > Jan
> >
> > >
> > > Signed-off-by: Jan Remmet <j.remmet at phytec.de>
> > > ---
> > > common/Kconfig | 1 +
> > > common/imx-bbu-nand-fcb.c | 145 +++++++++++++++++++++++++++++++++++++++++++++-
> > > 2 files changed, 143 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/common/Kconfig b/common/Kconfig
> > > index ed472a0..a10caf6 100644
> > > --- a/common/Kconfig
> > > +++ b/common/Kconfig
> > > @@ -101,6 +101,7 @@ config BAREBOX_UPDATE_IMX_NAND_FCB
> > > depends on BAREBOX_UPDATE
> > > depends on MTD_WRITE
> > > depends on NAND_MXS
> > > + select BCH if ARCH_IMX6
> > > default y
> > >
> > > config UBIFORMAT
> > > diff --git a/common/imx-bbu-nand-fcb.c b/common/imx-bbu-nand-fcb.c
> > > index 34a5f83..5d3d3f7 100644
> > > --- a/common/imx-bbu-nand-fcb.c
> > > +++ b/common/imx-bbu-nand-fcb.c
> > > @@ -33,9 +33,12 @@
> > > #include <linux/mtd/mtd.h>
> > > #include <linux/mtd/nand.h>
> > > #include <linux/stat.h>
> > > +#include <linux/bch.h>
> > > +#include <linux/bitops.h>
> > > #include <io.h>
> > > #include <crc.h>
> > > #include <mach/generic.h>
> > > +#include <mach/imx6.h>
> > > #include <mtd/mtd-peb.h>
> > >
> > > struct dbbt_block {
> > > @@ -129,6 +132,132 @@ static uint8_t calculate_parity_13_8(uint8_t d)
> > > return p;
> > > }
> > >
> > > +static uint8_t reverse_bit(uint8_t b)
> > > +{
> > > + b = (b & 0xf0) >> 4 | (b & 0x0f) << 4;
> > > + b = (b & 0xcc) >> 2 | (b & 0x33) << 2;
> > > + b = (b & 0xaa) >> 1 | (b & 0x55) << 1;
> > > +
> > > + return b;
> > > +}
> > > +
> > > +static void encode_bch_ecc(void *buf, struct fcb_block *fcb, int eccbits)
> > > +{
> > > + int i, j, m = 13;
> > > + int blocksize = 128;
> > > + int numblocks = 8;
> > > + int ecc_buf_size = (m * eccbits + 7) / 8;
> > > + struct bch_control *bch = init_bch(m, eccbits, 0);
> > > + uint8_t *ecc_buf = xmalloc(ecc_buf_size);
> > > + uint8_t *tmp_buf = xzalloc(blocksize * numblocks);
> > > + uint8_t *psrc, *pdst;
> > > +
> > > + /*
> > > + * The blocks here are bit aligned. If eccbits is a multiple of 8,
> > > + * we just can copy bytes. Otherwiese we must move the blocks to
> > > + * the next free bit position.
> > > + */
> > > + BUG_ON(eccbits % 8);
> > > +
> > > + memcpy(tmp_buf, fcb, sizeof(*fcb));
> > > +
> > > + for (i = 0; i < numblocks; i++) {
> > > + memset(ecc_buf, 0, ecc_buf_size);
> > > + psrc = tmp_buf + i * blocksize;
> > > + pdst = buf + i * (blocksize + ecc_buf_size);
> > > +
> > > + /* copy data byte aligned to destination buf */
> > > + memcpy(pdst, psrc, blocksize);
> > > +
> > > + /*
> > > + * imx-kobs use a modified encode_bch which reverse the
> > > + * bit order of the data before calculating bch.
> > > + * Do this in the buffer and use the bch lib here.
> > > + */
> > > + for (j = 0; j < blocksize; j++)
> > > + psrc[j] = reverse_bit(psrc[j]);
> > > +
> > > + encode_bch(bch, psrc, blocksize, ecc_buf);
> > > +
> > > + /* reverse ecc bit */
> > > + for (j = 0; j < ecc_buf_size; j++)
> > > + ecc_buf[j] = reverse_bit(ecc_buf[j]);
> > > +
> > > + /* Here eccbuf is byte aligned and we can just copy it */
> > > + memcpy(pdst + blocksize, ecc_buf, ecc_buf_size);
> > > + }
> > > +
> > > + free(ecc_buf);
> > > + free(tmp_buf);
> > > + free_bch(bch);
> > > +}
> > > +
> > > +struct fcb_block *read_fcb_bch(void *rawpage, int eccbits)
> > > +{
> > > + int i, j, ret, errbit, m = 13;
> > > + int blocksize = 128;
> > > + int numblocks = 8;
> > > + int ecc_buf_size = (m * eccbits + 7) / 8;
> > > + struct bch_control *bch = init_bch(m, eccbits, 0);
> > > + uint8_t *fcb = xmalloc(numblocks * blocksize);
> > > + uint8_t *ecc_buf = xmalloc(ecc_buf_size);
> > > + uint8_t *data_buf = xmalloc(blocksize);
> > > + unsigned int *errloc = xmalloc(eccbits * sizeof(*errloc));
> > > + uint8_t *psrc, *pdst;
> > > +
> > > + /* see encode_bch_ecc */
> > > + BUG_ON(eccbits % 8);
> > > +
> > > + for (i = 0; i < numblocks; i++) {
> > > + psrc = rawpage + 32 + i * (blocksize + ecc_buf_size);
> > > + pdst = fcb + i * blocksize;
> > > +
> > > + /* reverse data bit */
> > > + for (j = 0; j < blocksize; j++)
> > > + data_buf[j] = reverse_bit(psrc[j]);
> > > +
> > > + /* reverse ecc bit */
> > > + for (j = 0; j < ecc_buf_size; j++)
> > > + ecc_buf[j] = reverse_bit(psrc[j + blocksize]);
> > > +
> > > + ret = decode_bch(bch, data_buf, blocksize, ecc_buf,
> > > + NULL, NULL, errloc);
> > > +
> > > + if (ret < 0) {
> > > + pr_err("Uncorrectable error at block %d\n", i);
> > > + free(fcb);
> > > + fcb = ERR_PTR(ret);
> > > + goto out;
> > > + }
> > > + if (ret > 0)
> > > + pr_info("Found %d correctable errors in block %d\n",
> > > + ret, i);
> > > +
> > > + for (j = 0; j < ret; j++) {
> > > + /*
> > > + * calculate the reverse position
> > > + * pos - (pos % 8) -> byte offset
> > > + * 7 - (pos % 8) -> reverse bit position
> > > + */
> > > + errbit = errloc[j] - 2 * (errloc[j] % 8) + 7;
> > > + pr_debug("Found error: bit %d in block %d\n",
> > > + errbit, i);
> > > + if (errbit < blocksize * 8)
> > > + change_bit(errbit, psrc);
> > > + /* else error in ecc, ignore it */
> > > + }
> > > + memcpy(pdst, psrc, blocksize);
> > > + }
> > > +
> > > +out:
> > > + free(data_buf);
> > > + free(ecc_buf);
> > > + free(errloc);
> > > + free_bch(bch);
> > > +
> > > + return (struct fcb_block *)fcb;
> > > +}
> > > +
> > > static void encode_hamming_13_8(void *_src, void *_ecc, size_t size)
> > > {
> > > int i;
> > > @@ -312,7 +441,11 @@ static int read_fcb(struct mtd_info *mtd, int num, struct fcb_block **retfcb)
> > > goto err;
> > > }
> > >
> > > - fcb = read_fcb_hamming_13_8(rawpage);
> > > + if (cpu_is_mx6ul())
> > > + fcb = read_fcb_bch(rawpage, 40);
> > > + else
> > > + fcb = read_fcb_hamming_13_8(rawpage);
> > > +
> > > if (IS_ERR(fcb)) {
> > > pr_err("Cannot read fcb\n");
> > > ret = PTR_ERR(fcb);
> > > @@ -766,8 +899,14 @@ static int imx_bbu_write_fcbs_dbbts(struct mtd_info *mtd, struct fcb_block *fcb)
> > >
> > > fcb_raw_page = xzalloc(mtd->writesize + mtd->oobsize);
> > >
> > > - memcpy(fcb_raw_page + 12, fcb, sizeof(struct fcb_block));
> > > - encode_hamming_13_8(fcb_raw_page + 12, fcb_raw_page + 12 + 512, 512);
> > > + if (cpu_is_mx6ul()) {
> > > + /* 40 bit BCH, for i.MX6UL */
> > > + encode_bch_ecc(fcb_raw_page + 32, fcb, 40);
> > > + } else {
> > > + memcpy(fcb_raw_page + 12, fcb, sizeof(struct fcb_block));
> > > + encode_hamming_13_8(fcb_raw_page + 12,
> > > + fcb_raw_page + 12 + 512, 512);
> > > + }
> > >
> > > dbbt = dbbt_data_create(mtd);
> > >
> > > --
> > > 2.7.4
> > >
> > >
> > > _______________________________________________
> > > barebox mailing list
> > > barebox at lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/barebox
> >
> > _______________________________________________
> > barebox mailing list
> > barebox at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/barebox
> >
>
> --
> Pengutronix e.K. | |
> Industrial Linux Solutions | http://www.pengutronix.de/ |
> Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
>
> _______________________________________________
> barebox mailing list
> barebox at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/barebox
More information about the barebox
mailing list