[PATCH V2 2/5] fdtdec: Add weak function to patch U-Boot DT right after fdtdec_setup()

[Bin Meng]

On Tue, May 19, 2020 at 8:40 PM Marek Vasut <marek.vasut at gmail.com> wrote:
>
> Add weak function which is called right after fdtdec_setup() configured
> the U-Boot DT. This permits board-specific adjustments to the U-Boot DT
> before U-Boot starts parsing the DT. This could be used e.g. to patch in
> various custom nodes or merge in DT fragments from prior-stage firmware.
>
> Signed-off-by: Marek Vasut <marek.vasut+renesas at gmail.com>
> Cc: Nobuhiro Iwamatsu <iwamatsu at nigauri.org>
> Cc: Simon Glass <sjg at chromium.org>
> Cc: Tom Rini <trini at konsulko.com>
> ---
> V2: Add the function to fdtdec.h
> ---
>  include/fdtdec.h |  5 +++++
>  lib/fdtdec.c     | 11 ++++++++++-
>  2 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/include/fdtdec.h b/include/fdtdec.h
> index 166f29c55b..abd6d42671 100644
> --- a/include/fdtdec.h
> +++ b/include/fdtdec.h
> @@ -1155,6 +1155,11 @@ int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
>   */
>  int fdtdec_setup(void);
>
> +/**
> + * Perform board-specific early DT adjustments
> + */
> +int fdtdec_board_setup(const void *fdt_blob);
> +
>  #if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
>  /**
>   * fdtdec_resetup()  - Set up the device tree again
> diff --git a/lib/fdtdec.c b/lib/fdtdec.c
> index 0a3b860782..f366dcedb8 100644
> --- a/lib/fdtdec.c
> +++ b/lib/fdtdec.c
> @@ -1472,8 +1472,14 @@ int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
>         return 0;
>  }
>
> +__weak int fdtdec_board_setup(const void *fdt_blob)
> +{
> +       return 0;
> +}
> +
>  int fdtdec_setup(void)
>  {
> +       int ret;
>  #if CONFIG_IS_ENABLED(OF_CONTROL)
>  # if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
>         void *fdt_blob;
> @@ -1526,7 +1532,10 @@ int fdtdec_setup(void)
>  # endif
>  #endif
>
> -       return fdtdec_prepare_fdt();
> +       ret = fdtdec_prepare_fdt();
> +       if (!ret)
> +               ret = fdtdec_board_setup(gd->fdt_blob);
> +       return ret;
>  }

There is already a CONFIG_OF_BOARD_FIXUP (fix_fdt) in board_f.c

Should we consider moving that into fdtdec_setup()?

Regards,
Bin