[PATCH v1] mtd: nand: raw: rockchip_nfc: copy hwecc PA data to oob_poi buffer

[Kever Yang]

On 2023/6/22 21:59, Johan Jonker wrote:
> Rockchip boot blocks are written per 4 x 512 byte sectors per page.
> Each page must have a page address (PA) pointer in OOB to the next page.
> Pages are written in a pattern depending on the NAND chip ID.
> This logic used to build a page pattern table is not fully disclosed and
> is not easy to fit in the MTD framework.
> The formula in rk_nfc_write_page_hwecc() function is not correct.
> Make hwecc and raw behavior identical.
> Generate boot block page address and pattern for hwecc in user space
> and copy PA data to/from the already reserved last 4 bytes before EEC
> in the chip->oob_poi data layout.
>
> Signed-off-by: Johan Jonker <jbx6244 at gmail.com>
Reviewed-by: Kever Yang <kever.yang at rock-chips.com>

Thanks,
- Kever
> ---
>   drivers/mtd/nand/raw/rockchip_nfc.c | 34 ++++++++++++++++++-----------
>   1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/rockchip_nfc.c b/drivers/mtd/nand/raw/rockchip_nfc.c
> index 5fcf6a6b..274489ec 100644
> --- a/drivers/mtd/nand/raw/rockchip_nfc.c
> +++ b/drivers/mtd/nand/raw/rockchip_nfc.c
> @@ -525,7 +525,7 @@ static int rk_nfc_write_page_hwecc(struct mtd_info *mtd,
>   	int pages_per_blk = mtd->erasesize / mtd->writesize;
>   	int ret = 0, i, boot_rom_mode = 0;
>   	dma_addr_t dma_data, dma_oob;
> -	u32 reg;
> +	u32 tmp;
>   	u8 *oob;
>
>   	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
> @@ -552,6 +552,13 @@ static int rk_nfc_write_page_hwecc(struct mtd_info *mtd,
>   	 *
>   	 *   0xFF 0xFF 0xFF 0xFF | BBM OOB1 OOB2 OOB3 | ...
>   	 *
> +	 * The code here just swaps the first 4 bytes with the last
> +	 * 4 bytes without losing any data.
> +	 *
> +	 * The chip->oob_poi data layout:
> +	 *
> +	 *    BBM  OOB1 OOB2 OOB3 |......|  PA0  PA1  PA2  PA3
> +	 *
>   	 * Configure the ECC algorithm supported by the boot ROM.
>   	 */
>   	if (page < (pages_per_blk * rknand->boot_blks)) {
> @@ -561,21 +568,17 @@ static int rk_nfc_write_page_hwecc(struct mtd_info *mtd,
>   	}
>
>   	for (i = 0; i < ecc->steps; i++) {
> -		if (!i) {
> -			reg = 0xFFFFFFFF;
> -		} else {
> +		if (!i)
> +			oob = chip->oob_poi + (ecc->steps - 1) * NFC_SYS_DATA_SIZE;
> +		else
>   			oob = chip->oob_poi + (i - 1) * NFC_SYS_DATA_SIZE;
> -			reg = oob[0] | oob[1] << 8 | oob[2] << 16 |
> -			      oob[3] << 24;
> -		}
>
> -		if (!i && boot_rom_mode)
> -			reg = (page & (pages_per_blk - 1)) * 4;
> +		tmp = oob[0] | oob[1] << 8 | oob[2] << 16 | oob[3] << 24;
>
>   		if (nfc->cfg->type == NFC_V9)
> -			nfc->oob_buf[i] = reg;
> +			nfc->oob_buf[i] = tmp;
>   		else
> -			nfc->oob_buf[i * (oob_step / 4)] = reg;
> +			nfc->oob_buf[i * (oob_step / 4)] = tmp;
>   	}
>
>   	dma_data = dma_map_single((void *)nfc->page_buf,
> @@ -720,12 +723,17 @@ static int rk_nfc_read_page_hwecc(struct mtd_info *mtd,
>   		goto timeout_err;
>   	}
>
> -	for (i = 1; i < ecc->steps; i++) {
> -		oob = chip->oob_poi + (i - 1) * NFC_SYS_DATA_SIZE;
> +	for (i = 0; i < ecc->steps; i++) {
> +		if (!i)
> +			oob = chip->oob_poi + (ecc->steps - 1) * NFC_SYS_DATA_SIZE;
> +		else
> +			oob = chip->oob_poi + (i - 1) * NFC_SYS_DATA_SIZE;
> +
>   		if (nfc->cfg->type == NFC_V9)
>   			tmp = nfc->oob_buf[i];
>   		else
>   			tmp = nfc->oob_buf[i * (oob_step / 4)];
> +
>   		*oob++ = (u8)tmp;
>   		*oob++ = (u8)(tmp >> 8);
>   		*oob++ = (u8)(tmp >> 16);
> --
> 2.30.2
>