[U-Boot] [PATCH v2] Make FIT support really optional

[Carlos Santos <casantos@datacom.ind.br>]

> From: "Tom Rini" <trini@konsulko.com>
> To: "Carlos Santos" <casantos@datacom.ind.br>
> Cc: u-boot at lists.denx.de
> Sent: Saturday, June 4, 2016 10:06:58 AM
> Subject: Re: [U-Boot] [PATCH v2] Make FIT support really optional

> On Fri, Jun 03, 2016 at 04:16:26PM -0300, Carlos Santos wrote:
> 
>> Due to some mistakes in the source code, it was not possible to really
>> turn FIT support off. This commit fixes the problem by means of the
>> following changes:
>> 
>> - Enclose "bootm_host_load_image" and "bootm_host_load_images" between
>>   checks for CONFIG_FIT_SIGNATURE, in common/bootm.c.
>> 
>> - Enclose the declaration of "bootm_host_load_images" between checks for
>>   CONFIG_FIT_SIGNATURE, in common/bootm.h.
>> 
>> - Condition the compilation and linking of fit_common.o fit_image.o
>>   image-host.o common/image-fit.o to CONFIG_FIT=y, in tools/Makefile.
>> 
>> Signed-off-by: Carlos Santos <casantos@datacom.ind.br>
>> ---
>> Changes v1 -> v2
>>  Rebased to the top of master branch.
>> 
>>  common/bootm.c  | 2 ++
>>  include/bootm.h | 2 ++
>>  tools/Makefile  | 6 ++----
>>  3 files changed, 6 insertions(+), 4 deletions(-)
> 
> So, why?  I don't like the idea of making FIT support in mkimage
> conditional.

If FIT is not to be conditional then what's the purpose of the CONFIG_FIT_SIGNATURE configuration option? Looks like it exists exactly to make FIT support conditional, which seems to be a reasonable approach, since it helps to reduce the size of the boot loader.

> This makes the life of distribution people harder, not
> easier.  The functions in common/bootm.c should be being discarded in
> U-Boot itself when we don't have CONFIG_FIT_SIGNATURE.  Thanks!

The patch exists because of "distribution people". I sent a patch to Buildroot[1] which was refused because it added dependencies on DTC and evolved to several follow-ups [2,3,4].

1. http://patchwork.ozlabs.org/patch/618486/
2. http://patchwork.ozlabs.org/patch/619278/
3. http://patchwork.ozlabs.org/patch/619696/
4. http://patchwork.ozlabs.org/patch/629988/

Carlos Santos (Casantos)
DATACOM, P&D