Re: [edk2-devel] [PATCH edk2-platforms 2/2] Platform/DeveloperBox: disable variable runtime cache

["Leif Lindholm" <leif.lindholm@linaro.org>]

On Thu, Nov 28, 2019 at 16:04:29 +0100, Ard Biesheuvel wrote:
> On Thu, 28 Nov 2019 at 16:02, Leif Lindholm <leif.lindholm@linaro.org> wrote:
> >
> > On Thu, Nov 28, 2019 at 15:48:40 +0100, Ard Biesheuvel wrote:
> > > The variable runtime cache for SMM enabled implementations of the
> > > variable runtime DXE driver was introduced after the standalone
> > > MM based implementation was merged for the DeveloperBox platform.
> > >
> > > This means the combined binary image of ARM Trusted Firmware and
> > > the standalone MM runtime we carry in edk2-non-osi predates this
> > > feature, so we need to disable it when building the non-secure side
> > > when incorporating the prebuilt binary.
> >
> > Is this something that needs to be explicitly disabled in current
> > upstream TF? (And if so, could we add a comment to edk2-non-osi
> > README?) Or does this only affect the requests made from Non-secure
> > side?
> 
> No, it has to be disabled on both sides. But this .dsc.inc gets
> included by both sides when you build them from scratch.

Oh, right. That's fine then.

> > > Whether it makes sense to enable the runtime cache for this platform
> > > is a different question, so let's keep it enabled entirely until
> >
> > enabled -> disabled?
> 
> Yep

With that:
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>


> >
> > > someone identifies a need for it.
> > >
> > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> > > ---
> > >  Platform/Socionext/DeveloperBox/DeveloperBox.dsc.inc | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/Platform/Socionext/DeveloperBox/DeveloperBox.dsc.inc b/Platform/Socionext/DeveloperBox/DeveloperBox.dsc.inc
> > > index a10e48ca07ea..084b4c994b97 100644
> > > --- a/Platform/Socionext/DeveloperBox/DeveloperBox.dsc.inc
> > > +++ b/Platform/Socionext/DeveloperBox/DeveloperBox.dsc.inc
> > > @@ -130,6 +130,8 @@ [PcdsFeatureFlag]
> > >    # needed for NFIT tables installed by RamDiskDxe
> > >    gEfiMdeModulePkgTokenSpaceGuid.PcdInstallAcpiSdtProtocol|TRUE
> > >
> > > +  gEfiMdeModulePkgTokenSpaceGuid.PcdEnableVariableRuntimeCache|FALSE
> > > +
> > >  [PcdsFixedAtBuild.common]
> > >  !ifdef $(FIRMWARE_VENDOR)
> > >    gEfiMdeModulePkgTokenSpaceGuid.PcdFirmwareVendor|L"$(FIRMWARE_VENDOR)"
> > > --
> > > 2.20.1
> > >
> 
> 
>