[PATCH] smbios: Fix calculating BIOS Release Date

[Bin Meng]

Hi Pali,

On Fri, Apr 23, 2021 at 12:10 AM Pali Rohár <pali at kernel.org> wrote:
>
> BIOS Release Date must be in format mm/dd/yyyy and must be release date.
> U-Boot currently sets BIOS Release Date from U_BOOT_DMI_DATE macro which is
> generated from current build timestamp.
>
> Fix this issue by setting U_BOOT_DMI_DATE macro to U-Boot version which is
> better approximation of U-Boot release date than current build timestamp.
> Current U-Boot versioning is in format yyyy.mm so as a day choose 01.
>
> Some operating systems are using BIOS Release Date for detecting when was
> SMBIOS table filled or if it could support some feature (e.g. BIOS from
> 1990 cannot support features invented in 2000). So this change also ensures
> that recompiling U-Boot from same sources but in different year does not
> change behavior of some operating systems.
>
> Macro U_BOOT_DMI_DATE is not used in other file than lib/smbios.c
> so remove it from global autogenerated files and also from Makefile.
>
> Signed-off-by: Pali Rohár <pali at kernel.org>
> ---
>  Makefile                |  2 --
>  doc/develop/version.rst |  1 -
>  lib/smbios.c            | 23 +++++++++++++++++++++++
>  3 files changed, 23 insertions(+), 3 deletions(-)
>

With this change the U-Boot date is only the release date, so one
cannot tell exact BIOS date on which U-Boot was built from.

Regards,
Bin