[PATCH] mx8m: csf.sh: pad csf blob for u-boot.itb to CSF_SIZE minus IVT header

[Marek Vasut]

On 9/19/23 12:00, Rasmus Villemoes wrote:
> When built with CONFIG_IMX_HAB, the full FIT image, including stuff
> tacked on beyond the end of the fdt structure, is expected to be (fdt
> size rounded up to 0x1000 boundary)+CONFIG_CSF_SIZE.
> 
> Now, when the FIT image is loaded from a storage device, it doesn't
> really matter that the flash.bin that gets written to target isn't
> quite that big - we will just load some garbage bytes that are never
> read or used for anything. But when flash.bin is uploaded via uuu,
> it's important that we actually serve at least as many bytes as the
> target expects, or we will hang in rom_api_download_image().
> 
> Extend the logic in the csf.sh script so that the csf blob is padded
> to CONFIG_CSF_SIZE minus the size of the IVT header.

On which SoC do you trigger this stuff ?
(or rather, which bootrom version, v1 or v2? they each use SDP or SDPS 
respectively)

> Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
> ---
>   doc/imx/habv4/csf_examples/mx8m/csf.sh | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/doc/imx/habv4/csf_examples/mx8m/csf.sh b/doc/imx/habv4/csf_examples/mx8m/csf.sh
> index 65c143073c..80edc94aeb 100644
> --- a/doc/imx/habv4/csf_examples/mx8m/csf.sh
> +++ b/doc/imx/habv4/csf_examples/mx8m/csf.sh
> @@ -75,5 +75,13 @@ dd if=ivt.bin of=flash.bin bs=1 seek=${ivt_block_offset} conv=notrunc
>   
>   # Generate CSF blob
>   cst -i csf_fit.tmp -o csf_fit.bin
> +
> +# When loading flash.bin via USB, we must ensure that the file being
> +# served is as large as the target expects (see
> +# board_spl_fit_size_align()), otherwise the target will hang in
> +# rom_api_download_image() waiting for the remaining bytes.
> +CSF_SIZE=$(sed -n "/CONFIG_CSF_SIZE=/ s at .*=@@p" .config)
> +truncate -s $((CSF_SIZE - 0x20)) csf_fit.bin

Can you use dd(1) instead ? I think dd(1) is more portable than 
truncate(1) , at least I cannot find truncate(1) in opengroup specs.