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

[Marek Vasut]

On 5/19/20 3:33 PM, Bin Meng wrote:
> 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()?

This one is run much earlier and this is the only fitting location.