Re: [edk2-devel] [PATCH V2 0/6] Support 5-level paging in DXE long mode

["Michael D Kinney" <michael.d.kinney@intel.com>]

Hi Ray,

Given that there may be register definitions for other
CPUs or devices added to MdePkg in the future, should
an extra directory level be added?  Doing that would
break source compatibility for existing components that
use #include <Register/Cpuid.h> from UefiCpuPkg.  We could
keep Cpuid.h in UefiCpuPkg, and it could be a #include
of the new Cpuid.h file in the MdePkg in the extended path.

Also, should CpuId.h be included from BaseLib.h inside:

  #if defined (MDE_CPU_IA32) || defined (MDE_CPU_X64)

This would make all CPUID related register definitions
available to components the needs BaseLib to call
AsmCpuId() or AsmCpuIdEx()?

We could also move the CRx, FLAGS/EFLAGS/descriptor
structures out of BaseLib.h into include files that
are peers to Cpuid.h and could be updated based on
public spec updates.

Thanks,

Mike

> -----Original Message-----
> From: devel@edk2.groups.io
> [mailto:devel@edk2.groups.io] On Behalf Of Ni, Ray
> Sent: Wednesday, July 24, 2019 3:00 AM
> To: devel@edk2.groups.io
> Subject: [edk2-devel] [PATCH V2 0/6] Support 5-level
> paging in DXE long mode
> 
> v2:
>    Refined the patch according to reviewers' all
> comments except:
>       0A0h cannot be changed to A0h or build fails.
>    A big change in this patch is Cpuid.h is moved from
> UefiCpuPkg to MdePkg.
>    The move is based on real requirement when certain
> modules that cannot
>    depend on UefiCpuPkg but needs to reference
> structures defined in SDM.
> 
> Ray Ni (6):
>   UefiCpuPkg/MpInitLib: Enable 5-level paging for AP
> when BSP's enabled
>   UefiCpuPkg/CpuDxe: Remove unnecessary macros
>   UefiCpuPkg/CpuDxe: Support parsing 5-level page table
>   MdeModulePkg/DxeIpl: Introduce PCD
> PcdUse5LevelPageTable
>   MdePkg/Cpuid.h: Move Cpuid.h from UefiCpuPkg to
> MdePkg
>   MdeModulePkg/DxeIpl: Create 5-level page table for
> long mode
> 
>  MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf       |   1 +
>  .../Core/DxeIplPeim/X64/VirtualMemory.c       | 229
> ++++++++++++------
>  MdeModulePkg/MdeModulePkg.dec                 |   7 +
>  MdeModulePkg/MdeModulePkg.uni                 |   8 +
>  .../Include/Register/Cpuid.h                  |   0
>  UefiCpuPkg/CpuDxe/CpuPageTable.c              |  59
> +++--
>  UefiCpuPkg/CpuDxe/CpuPageTable.h              |   3 +-
>  UefiCpuPkg/Library/MpInitLib/MpLib.c          |  13 +
>  UefiCpuPkg/Library/MpInitLib/MpLib.h          |   6 +-
>  UefiCpuPkg/Library/MpInitLib/X64/MpEqu.inc    |   3 +-
>  UefiCpuPkg/Library/MpInitLib/X64/MpFuncs.nasm |  14 +-
>  11 files changed, 243 insertions(+), 100 deletions(-)
> rename {UefiCpuPkg => MdePkg}/Include/Register/Cpuid.h
> (100%)
> 
> --
> 2.21.0.windows.1
> 
> 
>