[PATCH 1/4] mkimage: also honour -B even without external data

[Rasmus Villemoes]

On 21/09/2023 03.02, Simon Glass wrote:
> Hi Rasmus,
> 
> On Tue, 19 Sept 2023 at 05:37, Rasmus Villemoes
> <rasmus.villemoes at prevas.dk> wrote:
>>
>> In some cases, using the "external data" feature is impossible or
>> undesirable, but one may still want (or need) the FIT image to have a
>> certain alignment. Also, given the current 'mkimage -h' output,
>>
>>   -B => align size in hex for FIT structure and header
>>
>> it is quite unexpected for -B to be effectively ignored without -E.
>>
>> Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
>> ---
>>  tools/fit_image.c | 40 ++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 40 insertions(+)
> 
> Reviewed-by: Simon Glass <sjg at chromium.org>
> 
> Q below
> 
>>
>> diff --git a/tools/fit_image.c b/tools/fit_image.c
>> index 9fe69ea0d9..2f5b25098a 100644
>> --- a/tools/fit_image.c
>> +++ b/tools/fit_image.c
>> @@ -712,6 +712,42 @@ err:
>>         return ret;
>>  }
>>
>> +/**
>> + * fit_align() - Ensure FIT image has certain alignment
>> + *
>> + * This takes a normal FIT file (with embedded data) and increases its
>> + * size so that it is a multiple of params->bl_len.
>> + */
>> +static int fit_align(struct image_tool_params *params, const char *fname)
>> +{
>> +       int fit_size, new_size;
>> +       int fd;
>> +       struct stat sbuf;
>> +       void *fdt;
>> +       int ret = 0;
>> +       int align_size;
>> +
>> +       align_size = params->bl_len;
>> +       fd = mmap_fdt(params->cmdname, fname, 0, &fdt, &sbuf, false, false);
>> +       if (fd < 0)
>> +               return -EIO;
>> +
>> +       fit_size = fdt_totalsize(fdt);
>> +       new_size = ALIGN(fit_size, align_size);
>> +       fdt_set_totalsize(fdt, new_size);
> 
> Shouldn't this be fdt_open_into()?

I honestly just copy-pasted fit_extract_data() and shaved it down to the
part that does the "align the FDT part of the file".

I don't really understand your question. Are you saying this doesn't
work (or maybe doesn't work in some cases), or are you saying that
there's a simpler way to do this? For the latter, sure, one doesn't
really need to parse the whole FDT; we could just

  open()
  pread() length from FDT header, convert to cpu-endianness
  length = ALIGN(length)
  pwrite() the new length in fdt-endianness
  ftruncate()
  close()

but I thought it was better to stay closer to how fit_extract_data() was
done.

Rasmus