I think it's a limitation of the existing implementation. Currently the
HobLength in EFI_HOB_GENERIC_HEADER is UINT16.
Thanks,
Dun
-----Original Message-----
From: Ard Biesheuvel <a...@kernel.org>
Sent: Wednesday, January 3, 2024 11:11 PM
To: Tan, Dun <dun....@intel.com>; Samer El-Haj-Mahmoud
<samer.el-haj-mahm...@arm.com>; Jose Marinho <jose.mari...@arm.com>
Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org>; Ni, Ray <ray...@intel.com>;
devel@edk2.groups.io
Subject: Re: [edk2-devel] [Patch V2 0/3] Move gMpInformationHobGuid from
StandaloneMmPkg to UefiCpuPkg.
(cc Samer and Jose)
Hello Dun Tan,
On Fri, 17 Nov 2023 at 10:57, Tan, Dun <dun....@intel.com> wrote:
>
> Hi Ard,
>
> I'm working on moving gMpInformationHobGuid from StandaloneMmPkg to
> UefiCpuPkg in this patch series. Currently in Edk2, the HOB is only consumed
> by StandaloneMmCpu.inf.
>
> As we know that this HOB is used to provide a lightweight static information
> of MP processor. However, there might be a concern that the maximum HOB size
> 64KB is not large enough when CPU number is 1~2000 or bigger.
>
> May I know if you considered this situation or is there any solution to avoid
> this issue on Arm?
>
I don't think this has ever come up. Is this maximum HOB size a PI limitation?
Or simply a limitation of the existing implementation?
>
> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of duntan
> Sent: Friday, November 17, 2023 5:40 PM
> To: devel@edk2.groups.io
> Subject: [edk2-devel] [Patch V2 0/3] Move gMpInformationHobGuid from
> StandaloneMmPkg to UefiCpuPkg.
>
> In the V2 patch set: Added more comments in the new MpInformation.h to
> document that some fields in this HOB may be invalidated.
>
> Move gMpInformationHobGuid from StandaloneMmPkg to UefiCpuPkg.
>
> Previously, the HOB is defined, created and consumed only in StandaloneMmPkg.
> The HOB contains the number of processors and EFI_PROCESSOR_INFORMATION
> structure. This is the same as the information that PiSmmCpuDxeSmm uses
> EfiMpServiceProtocolGuid to get.
>
> The incoming plan is to create gMpInformationHobGuid for both StandaloneMm
> and legacy DXE_SMM in early phase(for example in CpuMpPei). Then
> PiSmmCpuDxeSmm can consume the hob, which can simplify code logic in
> PiSmmCpuDxeSmm driver.
>
> So move this HOB definition to UefiCpuPkg in this patch series.
>
> Dun Tan (3):
> UefiCpuPkg: Create MpInformation.h in UefiCpuPkg
> StandaloneMmPkg:Add UefiCpuPkg.dec in DependencyCheck
> StandaloneMmPkg:Remove MpInformation.h
>
> StandaloneMmPkg/Drivers/StandaloneMmCpu/StandaloneMmCpu.inf
> | 1 +
>
> StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/StandaloneMmCoreEntryPoint.inf
> | 1 +
> StandaloneMmPkg/StandaloneMmPkg.ci.yaml
> | 3 ++-
> StandaloneMmPkg/StandaloneMmPkg.dec
> | 1 -
> {StandaloneMmPkg => UefiCpuPkg}/Include/Guid/MpInformation.h
> | 6 +++++-
> UefiCpuPkg/UefiCpuPkg.dec
> | 3 +++
> 6 files changed, 12 insertions(+), 3 deletions(-) rename
> {StandaloneMmPkg => UefiCpuPkg}/Include/Guid/MpInformation.h (71%)
>
> --
> 2.31.1.windows.1
>
>
>
>
>
>
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#113113): https://edk2.groups.io/g/devel/message/113113
Mute This Topic: https://groups.io/mt/102644629/21656
Group Owner: devel+ow...@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-
