Re: [PATCH v1 3/4] UefiCpuPkg: Add definitions for EDKII microcode patch HOB

["Ni, Ray" <ray.ni@intel.com>]

I suggest to let the DetectedPatchOffset points to the microcode header instead of microcode data.
Consumers can use the offset to get more information from header than just the microcode data.

> -----Original Message-----
> From: Wu, Hao A <hao.a.wu@intel.com>
> Sent: Tuesday, December 24, 2019 9:37 AM
> To: devel@edk2.groups.io
> Cc: Wu, Hao A <hao.a.wu@intel.com>; Dong, Eric <eric.dong@intel.com>; Ni,
> Ray <ray.ni@intel.com>; Laszlo Ersek <lersek@redhat.com>; Zeng, Star
> <star.zeng@intel.com>; Fu, Siyuan <siyuan.fu@intel.com>; Kinney, Michael
> D <michael.d.kinney@intel.com>
> Subject: [PATCH v1 3/4] UefiCpuPkg: Add definitions for EDKII microcode
> patch HOB
> 
> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2430
> 
> This commit will add the definitions for EDKII microcode patch HOB.
> 
> The intention of adding this HOB is to provide a scheme to store the below
> information:
> 
> A. The base address and size of the microcode patches that are being
>    loaded (from flash) into memory;
> B. The information of applied microcode patch for each processor within
>    the system.
> 
> The producer of the HOB will be the UefiCpuPkg/MpInitLib (where the load,
> detect and apply of the microcode happen). The consumer of the HOB can
> be
> modules that want to detect/apply the microcode patch by themselves again
> later during the boot flow.
> 
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Star Zeng <star.zeng@intel.com>
> Cc: Siyuan Fu <siyuan.fu@intel.com>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Signed-off-by: Hao A Wu <hao.a.wu@intel.com>
> ---
>  UefiCpuPkg/UefiCpuPkg.dec                   |  3 ++
>  UefiCpuPkg/Include/Guid/MicrocodePatchHob.h | 50
> ++++++++++++++++++++
>  2 files changed, 53 insertions(+)
> 
> diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec
> index 797f948631..45b267ac61 100644
> --- a/UefiCpuPkg/UefiCpuPkg.dec
> +++ b/UefiCpuPkg/UefiCpuPkg.dec
> @@ -63,6 +63,9 @@ [Guids]
>    ## Include/Guid/CpuFeaturesInitDone.h
>    gEdkiiCpuFeaturesInitDoneGuid  = { 0xc77c3a41, 0x61ab, 0x4143, { 0x98,
> 0x3e, 0x33, 0x39, 0x28, 0x6, 0x28, 0xe5 }}
> 
> +  ## Include/Guid/MicrocodePatchHob.h
> +  gEdkiiMicrocodePatchHobGuid    = { 0xd178f11d, 0x8716, 0x418e, { 0xa1,
> 0x31, 0x96, 0x7d, 0x2a, 0xc4, 0x28, 0x43 }}
> +
>  [Protocols]
>    ## Include/Protocol/SmmCpuService.h
>    gEfiSmmCpuServiceProtocolGuid  = { 0x1d202cab, 0xc8ab, 0x4d5c, { 0x94,
> 0xf7, 0x3c, 0xfc, 0xc0, 0xd3, 0xd3, 0x35 }}
> diff --git a/UefiCpuPkg/Include/Guid/MicrocodePatchHob.h
> b/UefiCpuPkg/Include/Guid/MicrocodePatchHob.h
> new file mode 100644
> index 0000000000..3667fc3786
> --- /dev/null
> +++ b/UefiCpuPkg/Include/Guid/MicrocodePatchHob.h
> @@ -0,0 +1,50 @@
> +/** @file
> +  The microcode patch HOB is used to store the information of:
> +    A. Base address and size of the loaded microcode patches data;
> +    B. Applied microcode patch for each processor within system.
> +
> +  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +  This program and the accompanying materials
> +  are licensed and made available under the terms and conditions of the BSD
> License
> +  which accompanies this distribution.  The full text of the license may be
> found at
> +  http://opensource.org/licenses/bsd-license.php.
> +
> +  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS"
> BASIS,
> +  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER
> EXPRESS OR IMPLIED.
> +
> +**/
> +
> +#ifndef _MICROCODE_PATCH_HOB_H_
> +#define _MICROCODE_PATCH_HOB_H_
> +
> +extern EFI_GUID gEdkiiMicrocodePatchHobGuid;
> +
> +//
> +// The EDKII microcode patch HOB will be produced by MpInitLib and it can
> be
> +// consumed by modules that want to detect/apply microcode patches.
> +//
> +typedef struct {
> +  //
> +  // The base address of the microcode patches data after being loaded into
> +  // memory.
> +  //
> +  UINT64    MicrocodePatchAddress;
> +  //
> +  // The total size of the loaded microcode patches.
> +  //
> +  UINT64    MicrocodePatchRegionSize;
> +  //
> +  // The number of processors within the system.
> +  //
> +  UINT32    ProcessorNumber;
> +  //
> +  // An array with 'ProcessorNumber' elements that stores the offset (with
> +  // regard to 'MicrocodePatchAddress') of the applied microcode patch for
> each
> +  // processor.
> +  // If no microcode patch is applied for certain processor, the relating
> +  // element will be set to MAX_UINT64.
> +  //
> +  UINT64    DetectedPatchOffset[0];
> +} EDKII_MICROCODE_PATCH_HOB;
> +
> +#endif
> --
> 2.12.0.windows.1