Re: [PATCH v2 0/4] FMP versioning support

[Takahiro Akashi <takahiro.akashi@linaro.org>]

On Mon, Mar 06, 2023 at 03:08:55PM +0900, Masahisa Kojima wrote:
> Hi Akashi-san,
> 
> On Sat, 4 Mar 2023 at 10:28, Takahiro Akashi <takahiro.akashi@linaro.org> wrote:
> >
> > Kojima-san,
> >
> > On Wed, Mar 01, 2023 at 06:15:18PM +0900, Masahisa Kojima wrote:
> > > Firmware version management is not implemented in the current
> > > FMP implementation. This series aims to add the versioning support
> > > in FMP.
> >
> > I think that you need to think of A/B update case, especially
> > when a capsule update is *reverted* to an older version.
> 
> A/B update(FWU) has their own version information in the Image Directory
> defined in FWU spec[1], this is not implemented yet on U-Boot.
> On second thought, I think A/B update(FWU) case should be excluded
> from the version management introduced by this series.

I don't think it's a good idea to have two different implementations
for normal case and A/B update unless there is a good reason when
we use the same FMP driver.

-Takahiro Akashi

> >
> > In addition, please don't forget in the next patch set:
> > - update the man page of mkeficapsule command
> > - add test cases (in pytest)
> 
> Yes, noted.
> 
> [1] https://developer.arm.com/documentation/den0118/a/
> 
> Thanks,
> Masahisa Kojima
> 
> >
> > -Takahiro Akashi
> >
> > > EDK2 reference implementation utilizes the FMP Payload Header
> > > inserted right before the capsule payload. With this series,
> > > U-Boot also follows the EDK2 implementation.
> > >
> > > Currently, there is no way to know the current running firmware
> > > version through the EFI interface. FMP->GetImageInfo() returns
> > > always 0 for the version number. So a user can not know that
> > > expected firmware is running after the capsule update.
> > >
> > > With this series applied, version number can be specified
> > > in the capsule file generation with mkeficapsule tool, then
> > > user can know the running firmware version through
> > > FMP->GetImageInfo() and ESRT.
> > >
> > > Note that this series does not mandate the FMP Payload Header,
> > > compatible with boards that are already using the existing
> > > U-Boot FMP implementation.
> > > If no FMP Payload Header is found in the capsule file, fw_version,
> > > lowest supported version, last attempt version and last attempt
> > > status is set to 0 and this is the same behavior as existing FMP
> > > implementation.
> > >
> > > Changes in v2:
> > > - add FMP Payload Header generation in mkeficapsule tool
> > >
> > > Masahisa Kojima (4):
> > >   efi_loader: store firmware version into FmpState variable
> > >   efi_loader: versioning support in GetImageInfo
> > >   efi_loader: check lowest supported version in capsule update
> > >   mkeficapsule: add FMP Payload Header
> > >
> > >  lib/efi_loader/efi_firmware.c | 271 ++++++++++++++++++++++++++++++----
> > >  tools/mkeficapsule.c          |  81 +++++++++-
> > >  2 files changed, 319 insertions(+), 33 deletions(-)
> > >
> > > --
> > > 2.17.1
> > >