ArmPlatformPkg/NorFlashDxe: initialize varstore headers eagerly
authorLaszlo Ersek <lersek@redhat.com>
Wed, 11 Apr 2018 20:18:24 +0000 (22:18 +0200)
committerLaszlo Ersek <lersek@redhat.com>
Thu, 12 Apr 2018 19:24:32 +0000 (21:24 +0200)
commit0f87c53d0d0eb7e7c003e209705ec79264e0852b
tree7b3d07bf4d0b37fd2c9ad858f6ae39a47f753caf
parent7ab26d51808bd4ffab2510091b062a91cf6a8c81
ArmPlatformPkg/NorFlashDxe: initialize varstore headers eagerly

The lazy initialization of the varstore FVB makes no longer sense at this
point:

- "mNorFlashInstanceTemplate.Initialize" is NULL;

- in NorFlashCreateInstance(), we only set Instance->Initialize to
  non-NULL -- namely NorFlashFvbInitialize() -- if the FVB stands for the
  variable store (see "ContainVariableStorage" / "SupportFvb");

- we call Instance->Initialize() from three places:

  - from NorFlashWriteSingleBlock(), which is too late for the variable
    read service ("variable write" depends on "variable read");

  - from InitializeFvAndVariableStoreHeaders(), but that is only reachable
    from NorFlashFvbInitialize(), i.e. recursively from
    Instance->Initialize() itself;

  - and from FvbRead(), which is never called by the variable driver, only
    by the FTW driver. However, the variable driver may read (not write)
    the memory-mapped varstore flash chip before the FTW driver is
    dispatched.

Therefore the lazy initialization is both superfluous and insufficient.
Initialize the varstore headers eagerly, before we install the FVB
protocol interface.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Supreeth Venkatesh <Supreeth.Venkatesh@arm.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Steve Capper <steve.capper@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.c
ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe.h
ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashFvbDxe.c