Re: [PATCH v4 0/5] Enhanced SMM support for AMD-based x86 systems.

[Marvin H?user <Marvin.Haeuser@outlook.com>]

Hi Leo,

Yes, that's right. That PCD would be the only needed to be set by the platform DSC.

Thanks,
Marvin

> -----Original Message-----
> From: Duran, Leo [mailto:leo.duran@amd.com]
> Sent: Thursday, October 5, 2017 4:57 PM
> To: 'Marvin H?user' <Marvin.Haeuser@outlook.com>; edk2-
> devel@lists.01.org
> Cc: Yao, Jiewen <jiewen.yao@intel.com>
> Subject: RE: [edk2] [PATCH v4 0/5] Enhanced SMM support for AMD-based
> x86 systems.
> 
> 
> 
> > -----Original Message-----
> > From: Marvin H?user [mailto:Marvin.Haeuser@outlook.com]
> > Sent: Wednesday, October 04, 2017 8:19 PM
> > To: edk2-devel@lists.01.org
> > Cc: Yao, Jiewen <jiewen.yao@intel.com>; Duran, Leo
> <leo.duran@amd.com>
> > Subject: RE: [edk2] [PATCH v4 0/5] Enhanced SMM support for AMD-based
> > x86 systems.
> >
> > Hey Jiewen,
> > Hey Leo,
> >
> > May I suggest replacing "StandardSignatureIsAuthenticAMD()" and the
> > PCDs introduced by the series with a Fixed "PcdCpuVendor" enum or alike?
> 
> Hi Marvin,
> I'm not sure I follow your suggestion.
> It seems like the platform .DSC would then need to set PcdCpuVendor to an
> appropriate value at build-time... No?
> Leo.
> 
> > The contra of "StandardSignatureIsAuthenticAMD()" is that it's a
> > runtime action. From my point of view, this has no notable advantage
> > as boards use either an Intel or an AMD chipset and hence the EDK2
> > Firmware Package has compilation-time knowledge of the target platform.
> > On the other hand, the PCDs introduced by this patch cause the contra
> > that the platform DSC must set the correct vendor-specific (intel, AMD)
> value.
> > If the code checked for the CPU Vendor PCD and used the correct values
> > based on that, the values for the other vendors would get optimized
> > away (no unnecessary runtime actions) and the platform package owner
> > does not need to worry about setting PCDs to AMD-specific values
> > except for the CPU Vendor PCD.
> > Backwards-compatibility could be ensured by defaulting to some
> > reserved value for the PCD and handling detection via
> > StandardSignatureIsAuthenticAMD() if the platform DSC does not change
> it.
> >
> > Thanks,
> > Marvin.
> >
> > > -----Original Message-----
> > > From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf
> > > Of Yao, Jiewen
> > > Sent: Thursday, October 5, 2017 2:49 AM
> > > To: Leo Duran <leo.duran@amd.com>; edk2-devel@lists.01.org
> > > Subject: Re: [edk2] [PATCH v4 0/5] Enhanced SMM support for
> > > AMD-based
> > > x86 systems.
> > >
> > > Hi Leo
> > > I do not suggest we introduce PcdCpuSmmSmramSaveStateMapOffset.
> > >
> > > This is unnecessary, because it is CPU attribute but not some end
> > > user configurable data.
> > >
> > > I think we can use CPUID to distinguish AMD from INTEL. Is that
> > > technically possible?
> > >
> > > I found we already have code at
> > >
> > >
> >
> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\BaseXApicX2ApicLib\BaseXApic
> > > X2ApicLib.c(1206):    if (StandardSignatureIsAuthenticAMD()) {
> > >
> > >
> >
> C:\home\EdkIIGit\edk2\UefiCpuPkg\Library\BaseXApicLib\BaseXApicLib.c(1
> > 1
> > > 11):    if (StandardSignatureIsAuthenticAMD()) {
> > >
> > >
> > >
> > > Thank you
> > > Yao Jiewen
> > >
> > >
> > > > -----Original Message-----
> > > > From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On
> > > > Behalf Of Leo Duran
> > > > Sent: Thursday, October 5, 2017 3:02 AM
> > > > To: edk2-devel@lists.01.org
> > > > Subject: [edk2] [PATCH v4 0/5] Enhanced SMM support for AMD-based
> > > > x86 systems.
> > > >
> > > > This patch-set introduces a couple of FixedPCDs to replace
> > > > Intel-specific macros, and better support AMD-based x86 systems.
> > > >
> > > > 1) PcdCpuSmmSmramSaveStateMapOffset - SMRAM Save State Map
> > > Offset.
> > > > 2) PcdCpuSmmPSDOffset - Processor SMM Descriptor Offset in
> SMRAM.
> > > >
> > > > Changes since v3:
> > > > Correction on cover letter.
> > > >
> > > > Changes since v2:
> > > > The intent of this revision is to maintain compatibility with
> > > > existing packages. To that end, changes to OvmgfPkg and
> > > > QuarkSocPkg are
> > > reverted.
> > > > Moreover, pertinent macros are replaced in the C code, rather than
> > > > on header files that are shared globally.
> > > >
> > > > Changes since v1:
> > > > Revision to Cc list for UefiCpuPkg.
> > > >
> > > > Leo Duran (5):
> > > >   UefiCpuPkg/UefiCpuPkg.dec: Create FixedPCDs for SMM support
> > > >   UefiCpuPkg/PiSmmCpuDxeSmm: Consume FixedPCDs to enhance
> SMM
> > > support
> > > >   UefiCpuPkg/PiSmmCpuDxeSmm: Use FixedPCDs to enhance SMM
> > > support
> > > >   UefiCpuPkg/SmmCpuFeaturesLib: Consume FixedPCD to enhance
> SMM
> > > > support
> > > >   UefiCpuPkg/SmmCpuFeaturesLib: Use FixedPCD on non-STM library
> > > >
> > > >  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c      |  4
> > > > +++-
> > > >  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf    |
> 5
> > > > +++++
> > > >  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf
> |
> > 5
> > > > +++++
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/Semaphore.c                    |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.S                     |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.asm                   |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm                  |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.c                    |
> > > > 10 +++++-----
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.h                    |
> > > > 2 --
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/PiSmmCpuDxeSmm.inf                  |
> > > > 4 ++++
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/SmmCpuMemoryManagement.c
> > > > |  4 +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c                    |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/X64/Semaphore.c                     |
> > > > 4 +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.S                      |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.asm                    |  4
> > > > +++-
> > > >  UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm                   |  4
> > > > +++-
> > > >  UefiCpuPkg/UefiCpuPkg.dec                                     |  9
> > > > +++++++++
> > > >  17 files changed, 61 insertions(+), 18 deletions(-)
> > > >
> > > > --
> > > > 2.7.4
> > > >
> > > > _______________________________________________
> > > > edk2-devel mailing list
> > > > edk2-devel@lists.01.org
> > > > https://lists.01.org/mailman/listinfo/edk2-devel
> > > _______________________________________________
> > > edk2-devel mailing list
> > > edk2-devel@lists.01.org
> > > https://lists.01.org/mailman/listinfo/edk2-devel