[U-Boot] [PATCH 1/2] i.MX6: nand: extend nandbcb command for imx6UL(L)

[Parthiban Nallathambi]

Hi Shyam,

On 8/13/19 3:40 PM, Shyam Saini wrote:
> Hi Parthiban,
> 
> Thanks a lot for working on this.

Still enabling SECURE_BOOT fails to boot. Am yet to figure out this.
Do you have secure boot working from NAND?

> 
> Please see comments below.
> 
>> Firmware Configuration Block(FCB) for imx6ul(l) needs to be
>> BCH encoded. This patch depends on [1].
>>
>> [1]: https://patchwork.ozlabs.org/project/uboot/list/?series=113810
>>
>> Signed-off-by: Parthiban Nallathambi <pn at denx.de>
>> ---
>>   arch/arm/mach-imx/Kconfig       |  1 +
>>   arch/arm/mach-imx/cmd_nandbcb.c | 72 ++++++++++++++++++++++++++++++++-
>>   2 files changed, 71 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
>> index aeb5493488..175bed601e 100644
>> --- a/arch/arm/mach-imx/Kconfig
>> +++ b/arch/arm/mach-imx/Kconfig
>> @@ -74,6 +74,7 @@ config CMD_HDMIDETECT
>>   config CMD_NANDBCB
>>          bool "i.MX6 NAND Boot Control Block(BCB) command"
>>          depends on NAND && CMD_MTDPARTS
>> +       select BCH if MX6UL || MX6ULL
>>          default y if ARCH_MX6 && NAND_MXS
>>          help
>>            Unlike normal 'nand write/erase' commands, this command update
>> diff --git a/arch/arm/mach-imx/cmd_nandbcb.c b/arch/arm/mach-imx/cmd_nandbcb.c
>> index 065b814b2e..34176ee6e4 100644
>> --- a/arch/arm/mach-imx/cmd_nandbcb.c
>> +++ b/arch/arm/mach-imx/cmd_nandbcb.c
>> @@ -14,8 +14,10 @@
>>
>>   #include <asm/io.h>
>>   #include <jffs2/jffs2.h>
>> +#include <linux/bch.h>
>>   #include <linux/mtd/mtd.h>
>>
>> +#include <asm/arch/sys_proto.h>
>>   #include <asm/mach-imx/imx-nandbcb.h>
>>   #include <asm/mach-imx/imximage.cfg>
>>   #include <mxs_nand.h>
>> @@ -25,6 +27,66 @@
>>   #define BF_VAL(v, bf)          (((v) & bf##_MASK) >> bf##_OFFSET)
>>   #define GETBIT(v, n)           (((v) >> (n)) & 0x1)
>>
>> +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);
>> +       u8 *ecc_buf = kzalloc(ecc_buf_size, GFP_KERNEL);
>> +       u8 *tmp_buf = kzalloc(blocksize * numblocks, GFP_KERNEL);
>> +       u8 *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.
>> +        */
>> +       WARN_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);
> 
> I have used kfree() instead of free() in entire nand bcb code
> So, I think for consistency reason it should be kfree here.
> 
> Could you please resend this patch with above mentioned changes.
> Other than this,

Thanks, will change it to kfree in v2.

> 
>>
>>   static u8 calculate_parity_13_8(u8 d)
>>   {
>>          u8 p = 0;
>> @@ -231,8 +293,14 @@ static int nandbcb_update(struct mtd_info *mtd, loff_t off, size_t size,
>>                  goto dbbt_data_page_err;
>>          }
>>
>> -       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 (is_mx6ul() || is_mx6ull()) {
>> +               /* 40 bit BCH, for i.MX6UL(L) */
>> +               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);
>> +       }
>>          /*
>>           * Set the first and second byte of OOB data to 0xFF, not 0x00. These
>>           * bytes are used as the Manufacturers Bad Block Marker (MBBM). Since
> 
> Acked-by: Shyam Saini <shyam.saini at amarulasolutions.com>
> 

-- 
Thanks,
Parthiban N

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