From c02eed8e5a5497f26f2163d44c2239f5549f9fb0 Mon Sep 17 00:00:00 2001
From: Dun Tan <dun.tan@intel.com>
Date: Tue, 7 Nov 2023 17:25:08 +0800
Subject: [PATCH] UefiCpuPkg: Create gMpInformationHobGuid2 in UefiCpuPkg

Create gMpInformationHobGuid2 in UefiCpuPkg.

Currently, there is a gMpInformationHobGuid defined,
created and consumed only in StandaloneMmPkg. The HOB
contains the EFI_PROCESSOR_INFORMATION structure for
each CPU and the number of processors. This is the same
as the information that PiSmmCpuDxeSmm uses MpService
Protocol to get.

This new gMpInformationHobGuid2 also contains the
NumberOfProcessors and the EFI_PROCESSOR_INFORMATION
for each CPU. Also the HOB is extended to support the
case that the maximum HOB length is not enough for all
CPU. So there might be more than one HOB instance in the
HOB list. Each HOB describes the corresponding CPU index
range.

The plan is to create gMpInformationHob2Guid in CpuMpPei
module(implemented in next commit). Then PiSmmCpuDxeSmm
and other MM_STANDALONE modules can consume the hob. This
can avoid calling MpService Protocol in PiSmmCpuDxeSmm.
Also the issue that one gMpInformationHobGuid might be not
enough when CPU number is 1~2000 or bigger can be solved.

Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
---
 UefiCpuPkg/Include/Guid/MpInformation2.h | 56 ++++++++++++++++++++++++
 UefiCpuPkg/UefiCpuPkg.dec                |  3 ++
 2 files changed, 59 insertions(+)
 create mode 100644 UefiCpuPkg/Include/Guid/MpInformation2.h

diff --git a/UefiCpuPkg/Include/Guid/MpInformation2.h b/UefiCpuPkg/Include/Guid/MpInformation2.h
new file mode 100644
index 0000000000..7a25fcc2f3
--- /dev/null
+++ b/UefiCpuPkg/Include/Guid/MpInformation2.h
@@ -0,0 +1,56 @@
+/** @file
+  EFI MP information protocol provides a lightweight MP_SERVICES_PROTOCOL.
+
+  MP information protocol only provides static information of MP processor.
+
+  If SwitchBSP or Enable/DisableAP in MP service is called between the HOB
+  production and HOB consumption, EFI_PROCESSOR_INFORMATION.StatusFlag field
+  in this HOB may be invalidated.
+
+  Copyright (c) 2023, Intel Corporation. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef MP_INFORMATION2_H_
+#define MP_INFORMATION2_H_
+
+#include <Protocol/MpService.h>
+#include <PiPei.h>
+#include <Ppi/SecPlatformInformation.h>
+
+#define MP_INFORMATION2_HOB_REVISION  1
+
+#define MP_INFORMATION2_GUID \
+  { \
+    0x417a7f64, 0xf4e9, 0x4b32, {0x84, 0x6a, 0x5c, 0xc4, 0xd8, 0x62, 0x18, 0x79}  \
+  }
+
+typedef struct {
+  EFI_PROCESSOR_INFORMATION    ProcessorInfo;
+  //
+  // Add more fields in future
+  //
+} MP_INFORMATION2_ENTRY;
+
+typedef struct {
+  UINT16                   NumberOfProcessors;
+  UINT16                   EntrySize;
+  UINT8                    Version;
+  UINT8                    Reserved[3];
+  UINT64                   ProcessorIndex;
+  MP_INFORMATION2_ENTRY    Entry[0];
+} MP_INFORMATION2_HOB_DATA;
+
+//
+// Producer of MP_INFORMATION2_HOB_DATA should assign sizeof (MP_INFORMATION2_ENTRY) to MP_INFORMATION2_HOB_DATA.EntrySize
+// Consumer of MP_INFORMATION2_HOB_DATA should use below macro or similar logic to get the individual entry
+// as the entry structure might be updated to include more information.
+//
+#define GET_MP_INFORMATION_ENTRY(MpInfoHobData, Index) \
+    (MP_INFORMATION2_ENTRY *)((UINTN)&((MP_INFORMATION2_HOB_DATA *)(MpInfoHobData))->Entry + (MpInfoHobData)->EntrySize * Index)
+
+extern EFI_GUID  gMpInformationHobGuid2;
+
+#endif
diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec
index 0b5431dbf7..61bd34ef17 100644
--- a/UefiCpuPkg/UefiCpuPkg.dec
+++ b/UefiCpuPkg/UefiCpuPkg.dec
@@ -85,6 +85,9 @@
   ## Include/Guid/SmmBaseHob.h
   gSmmBaseHobGuid      = { 0xc2217ba7, 0x03bb, 0x4f63, {0xa6, 0x47, 0x7c, 0x25, 0xc5, 0xfc, 0x9d, 0x73 }}
 
+  ## Include/Guid/MpInformation2.h
+  gMpInformationHobGuid2         = { 0x417a7f64, 0xf4e9, 0x4b32, {0x84, 0x6a, 0x5c, 0xc4, 0xd8, 0x62, 0x18, 0x79 }}
+
 [Protocols]
   ## Include/Protocol/SmmCpuService.h
   gEfiSmmCpuServiceProtocolGuid   = { 0x1d202cab, 0xc8ab, 0x4d5c, { 0x94, 0xf7, 0x3c, 0xfc, 0xc0, 0xd3, 0xd3, 0x35 }}