[PATCH v4 08/10] rockchip: binman: Use the skip-at-start prop in simple-bin image

[Simon Glass]

Hi Quentin,

On Wed, 9 Apr 2025 at 07:32, Quentin Schulz <quentin.schulz at cherry.de> wrote:
>
> Hi Simon,
>
> On 4/9/25 3:22 PM, Simon Glass wrote:
> > Hi Quentin,
> >
> > On Wed, 9 Apr 2025 at 04:57, Quentin Schulz <quentin.schulz at cherry.de> wrote:
> >>
> >> Hi Jonas, Simon,
> >>
> >> On 3/29/25 4:06 PM, Jonas Karlman wrote:
> >>> From: Simon Glass <sjg at chromium.org>
> >>>
> >>> The simple-bin image is normally written to MMC media at block 64, which
> >>> is a 32K offset from start of storage media.
> >>>
> >>> Set the skip-at-start property to 0x8000 (32 KiB) so that fdtmap and
> >>> other embedded binman symbols in the output binary is referencing image
> >>> offsets correctly.
> >>>
> >>
> >> Shouldn't we have this commit BEFORE we add the `fdtmap` node since we
> >> know it's wrong before this commit?
> >>
> >>> Signed-off-by: Simon Glass <sjg at chromium.org>
> >>> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
> >>> ---
> >>> Changes in v4:
> >>> - Drop defconfig changes
> >>> - Split from "VBE serial part H: Implement VBE on Rockchip RK3399"
> >>>
> >>> Changes in v2:
> >>> - Move this patch to the end of the series
> >>> - Drop 0x8000 offset for SPI
> >>> ---
> >>>    arch/arm/dts/rockchip-u-boot.dtsi | 3 ++-
> >>>    1 file changed, 2 insertions(+), 1 deletion(-)
> >>>
> >>> diff --git a/arch/arm/dts/rockchip-u-boot.dtsi b/arch/arm/dts/rockchip-u-boot.dtsi
> >>> index fb38b7b80c43..65b81bf58626 100644
> >>> --- a/arch/arm/dts/rockchip-u-boot.dtsi
> >>> +++ b/arch/arm/dts/rockchip-u-boot.dtsi
> >>> @@ -154,6 +154,7 @@
> >>>        simple-bin {
> >>>                filename = "u-boot-rockchip.bin";
> >>>                pad-byte = <0xff>;
> >>> +             skip-at-start = <0x8000>;
> >>>
> >>>                mkimage {
> >>>                        filename = "idbloader.img";
> >>> @@ -178,7 +179,7 @@
> >>>    #else
> >>>                u-boot-img {
> >>>    #endif
> >>> -                     offset = <CONFIG_SPL_PAD_TO>;
> >>> +                     offset = <(CONFIG_SPL_PAD_TO + 0x8000)>;
> >>
> >> This is confusing. The documentation states:
> >>
> >> """
> >> offset:
> >>       This sets the offset of an entry within the image or section containing
> >>       it.
> >> """
> >>
> >> My understanding is that it should be relative to the beginning of the
> >> image but this now needs the knowledge of where it will be stored on the
> >> MMC device (via the value in skip-at-start).
> >>
> >> Why is skip-at-start automatically deducted from offset?
> >
> > This is how binman works[1]. We are trying to use the feature designs
>
> Why is it deducted?

Are you asking why skip-at-start is deducted from the offset?

Regards,
Simon