[PATCH 1/3] mmc: fsl_esdhc_spl: Add support for loading proper U-Boot from unaligned location

[Peng Fan (OSS)]

在 2022/5/12 2:33, Pali Rohár 写道:
> This allows to concatenate SPL and proper U-Boot without extra alignment.
>
> Signed-off-by: Pali Rohár <pali at kernel.org>
> ---
>   drivers/mmc/fsl_esdhc_spl.c | 25 ++++++++++++++++++++++---
>   1 file changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/fsl_esdhc_spl.c b/drivers/mmc/fsl_esdhc_spl.c
> index 760f13d24018..e3175de16bab 100644
> --- a/drivers/mmc/fsl_esdhc_spl.c
> +++ b/drivers/mmc/fsl_esdhc_spl.c
> @@ -155,10 +155,21 @@ again:
>   	* Load U-Boot image from mmc into RAM
>   	*/
>   	code_len = CONFIG_SYS_MMC_U_BOOT_SIZE;
> -	blk_start = ALIGN(offset, mmc->read_bl_len) / mmc->read_bl_len;
> -	blk_cnt = ALIGN(code_len, mmc->read_bl_len) / mmc->read_bl_len;
> +	blk_start = offset / mmc->read_bl_len;
> +	blk_off = offset % mmc->read_bl_len;

Build fail because of blk_off not defined.

Regards,
Peng.
> +	blk_cnt = ALIGN(code_len, mmc->read_bl_len) / mmc->read_bl_len + 1;
> +	if (blk_off) {
> +		err = mmc->block_dev.block_read(&mmc->block_dev,
> +						blk_start, 1, tmp_buf);
> +		if (err != 1) {
> +			puts("spl: mmc read failed!!\n");
> +			hang();
> +		}
> +		blk_start++;
> +	}
>   	err = mmc->block_dev.block_read(&mmc->block_dev, blk_start, blk_cnt,
> -					(uchar *)CONFIG_SYS_MMC_U_BOOT_DST);
> +					(uchar *)CONFIG_SYS_MMC_U_BOOT_DST +
> +					(blk_off ? (mmc->read_bl_len - blk_off) : 0));
>   	if (err != blk_cnt) {
>   		puts("spl: mmc read failed!!\n");
>   #ifndef CONFIG_FSL_CORENET
> @@ -166,6 +177,14 @@ again:
>   #endif
>   		hang();
>   	}
> +	/*
> +	 * SDHC DMA may erase bytes at dst + bl_len - blk_off - 8
> +	 * due to unaligned access. So copy leading bytes from tmp_buf
> +	 * after SDHC DMA transfer.
> +	 */
> +	if (blk_off)
> +		memcpy((uchar *)CONFIG_SYS_MMC_U_BOOT_DST,
> +		       tmp_buf + blk_off, mmc->read_bl_len - blk_off);
>   
>   	/*
>   	* Clean d-cache and invalidate i-cache, to