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From: "Abdul Lateef Attar via groups.io" <AbdulLateef.Attar=amd.com@groups.io>
To: "devel@edk2.groups.io" <devel@edk2.groups.io>,
	"Zhai, MingXin (Duke)" <duke.zhai@amd.com>
Cc: "Xing, Eric" <Eric.Xing@amd.com>,
	"Fu, Igniculus" <Igniculus.Fu@amd.com>,
	"Chang, Abner" <Abner.Chang@amd.com>
Subject: Re: [edk2-devel] [PATCH 29/33] AMD/VanGoghBoard: Check in SmramSaveState module.
Date: Sat, 20 Jan 2024 14:37:50 +0000	[thread overview]
Message-ID: <IA1PR12MB6458722E8AFF5D8D567D181BE0772@IA1PR12MB6458.namprd12.prod.outlook.com> (raw)
In-Reply-To: <20240118065046.961-30-duke.zhai@amd.com>

[AMD Official Use Only - General]

Why overriding the PiSmmCpuDxeSmm driver?
UefiCpuPkg has AMD specific SaveStatelib library "UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf".

Thanks
AbduL

-----Original Message-----
From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of duke.zhai via groups.io
Sent: Thursday, January 18, 2024 12:21 PM
To: devel@edk2.groups.io
Cc: Xing, Eric <Eric.Xing@amd.com>; Zhai, MingXin (Duke) <duke.zhai@amd.com>; Fu, Igniculus <Igniculus.Fu@amd.com>; Chang, Abner <Abner.Chang@amd.com>
Subject: [edk2-devel] [PATCH 29/33] AMD/VanGoghBoard: Check in SmramSaveState module.

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From: Duke Zhai <Duke.Zhai@amd.com>


BZ #:4640

Initial SmramSaveState module.

This module provides services to access SMRAM Save State Map.



Signed-off-by: Ken Yao <ken.yao@amd.com>

Cc: Eric Xing <eric.xing@amd.com>

Cc: Duke Zhai <duke.zhai@amd.com>

Cc: Igniculus Fu <igniculus.fu@amd.com>

Cc: Abner Chang <abner.chang@amd.com>

---

 .../PiSmmCpuDxeSmm/SmramSaveState.c           | 715 ++++++++++++++++++

 1 file changed, 715 insertions(+)

 create mode 100644 Platform/AMD/VanGoghBoard/Override/edk2/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c



diff --git a/Platform/AMD/VanGoghBoard/Override/edk2/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c b/Platform/AMD/VanGoghBoard/Override/edk2/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c

new file mode 100644

index 0000000000..9e5a7d59fc

--- /dev/null

+++ b/Platform/AMD/VanGoghBoard/Override/edk2/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c

@@ -0,0 +1,715 @@

+/** @file

+  Implements SmramSaveState.c

+

+  Copyright (C) 2024 Advanced Micro Devices, Inc. All rights reserved.<BR>

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+/* This file includes code originally published under the following license. */

+

+/** @file

+Provides services to access SMRAM Save State Map

+

+Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>

+SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#include <PiSmm.h>

+

+#include <Library/SmmCpuFeaturesLib.h>

+

+#include <Library/BaseLib.h>

+#include <Library/BaseMemoryLib.h>

+#include <Library/SmmServicesTableLib.h>

+#include <Library/DebugLib.h>

+

+#include "PiSmmCpuDxeSmm.h"

+

+typedef struct {

+  UINT64    Signature;                                      // Offset 0x00

+  UINT16    Reserved1;                                      // Offset 0x08

+  UINT16    Reserved2;                                      // Offset 0x0A

+  UINT16    Reserved3;                                      // Offset 0x0C

+  UINT16    SmmCs;                                          // Offset 0x0E

+  UINT16    SmmDs;                                          // Offset 0x10

+  UINT16    SmmSs;                                          // Offset 0x12

+  UINT16    SmmOtherSegment;                                // Offset 0x14

+  UINT16    Reserved4;                                      // Offset 0x16

+  UINT64    Reserved5;                                      // Offset 0x18

+  UINT64    Reserved6;                                      // Offset 0x20

+  UINT64    Reserved7;                                      // Offset 0x28

+  UINT64    SmmGdtPtr;                                      // Offset 0x30

+  UINT32    SmmGdtSize;                                     // Offset 0x38

+  UINT32    Reserved8;                                      // Offset 0x3C

+  UINT64    Reserved9;                                      // Offset 0x40

+  UINT64    Reserved10;                                     // Offset 0x48

+  UINT16    Reserved11;                                     // Offset 0x50

+  UINT16    Reserved12;                                     // Offset 0x52

+  UINT32    Reserved13;                                     // Offset 0x54

+  UINT64    Reserved14;                                     // Offset 0x58

+} PROCESSOR_SMM_DESCRIPTOR;

+

+extern CONST PROCESSOR_SMM_DESCRIPTOR  gcPsd;

+

+//

+// EFER register LMA bit

+//

+#define LMA  BIT10

+

+///

+/// Macro used to simplify the lookup table entries of type CPU_SMM_SAVE_STATE_LOOKUP_ENTRY

+///

+#define SMM_CPU_OFFSET(Field)  OFFSET_OF (SMRAM_SAVE_STATE_MAP, Field)

+

+///

+/// Macro used to simplify the lookup table entries of type CPU_SMM_SAVE_STATE_REGISTER_RANGE

+///

+#define SMM_REGISTER_RANGE(Start, End)  { Start, End, End - Start + 1 }

+

+///

+/// Structure used to describe a range of registers

+///

+typedef struct {

+  EFI_SMM_SAVE_STATE_REGISTER    Start;

+  EFI_SMM_SAVE_STATE_REGISTER    End;

+  UINTN                          Length;

+} CPU_SMM_SAVE_STATE_REGISTER_RANGE;

+

+///

+/// Structure used to build a lookup table to retrieve the widths and offsets

+/// associated with each supported EFI_SMM_SAVE_STATE_REGISTER value

+///

+

+#define SMM_SAVE_STATE_REGISTER_SMMREVID_INDEX   1

+#define SMM_SAVE_STATE_REGISTER_IOMISC_INDEX     2

+#define SMM_SAVE_STATE_REGISTER_IOMEMADDR_INDEX  3

+#define SMM_SAVE_STATE_REGISTER_MAX_INDEX        4

+

+typedef struct {

+  UINT8      Width32;

+  UINT8      Width64;

+  UINT16     Offset32;

+  UINT16     Offset64Lo;

+  UINT16     Offset64Hi;

+  BOOLEAN    Writeable;

+} CPU_SMM_SAVE_STATE_LOOKUP_ENTRY;

+

+///

+/// Structure used to build a lookup table for the IOMisc width information

+///

+typedef struct {

+  UINT8                          Width;

+  EFI_SMM_SAVE_STATE_IO_WIDTH    IoWidth;

+} CPU_SMM_SAVE_STATE_IO_WIDTH;

+

+///

+/// Variables from SMI Handler

+///

+X86_ASSEMBLY_PATCH_LABEL  gPatchSmbase;

+X86_ASSEMBLY_PATCH_LABEL  gPatchSmiStack;

+X86_ASSEMBLY_PATCH_LABEL  gPatchSmiCr3;

+extern volatile UINT8     gcSmiHandlerTemplate[];

+extern CONST UINT16       gcSmiHandlerSize;

+

+//

+// Variables used by SMI Handler

+//

+IA32_DESCRIPTOR  gSmiHandlerIdtr;

+

+///

+/// Table used by GetRegisterIndex() to convert an EFI_SMM_SAVE_STATE_REGISTER

+/// value to an index into a table of type CPU_SMM_SAVE_STATE_LOOKUP_ENTRY

+///

+CONST CPU_SMM_SAVE_STATE_REGISTER_RANGE  mSmmCpuRegisterRanges[] = {

+  SMM_REGISTER_RANGE (EFI_SMM_SAVE_STATE_REGISTER_GDTBASE, EFI_SMM_SAVE_STATE_REGISTER_LDTINFO),

+  SMM_REGISTER_RANGE (EFI_SMM_SAVE_STATE_REGISTER_ES,      EFI_SMM_SAVE_STATE_REGISTER_RIP),

+  SMM_REGISTER_RANGE (EFI_SMM_SAVE_STATE_REGISTER_RFLAGS,  EFI_SMM_SAVE_STATE_REGISTER_CR4),

+  { (EFI_SMM_SAVE_STATE_REGISTER)0,                        (EFI_SMM_SAVE_STATE_REGISTER)0,      0}

+};

+

+///

+/// Lookup table used to retrieve the widths and offsets associated with each

+/// supported EFI_SMM_SAVE_STATE_REGISTER value

+///

+CONST CPU_SMM_SAVE_STATE_LOOKUP_ENTRY  mSmmCpuWidthOffset[] = {

+  { 0, 0, 0,                            0,                                    0,                                    FALSE },  //  Reserved

+

+  //

+  // CPU Save State registers defined in PI SMM CPU Protocol.

+  //

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64.GdtrBaseLoDword), SMM_CPU_OFFSET (x64.GdtrBaseHiDword), FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_GDTBASE  = 4

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64.IdtrBaseLoDword), SMM_CPU_OFFSET (x64.IdtrBaseHiDword), FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_IDTBASE  = 5

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64.LdtrBaseLoDword), SMM_CPU_OFFSET (x64.LdtrBaseHiDword), FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_LDTBASE  = 6

+  { 0, 0, 0,                            SMM_CPU_OFFSET (x64.GdtrLimit),       0,                                    FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_GDTLIMIT = 7

+  { 0, 0, 0,                            SMM_CPU_OFFSET (x64.IdtrLimit),       0,                                    FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_IDTLIMIT = 8

+  { 0, 0, 0,                            SMM_CPU_OFFSET (x64.LdtrLimit),       0,                                    FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_LDTLIMIT = 9

+  { 0, 0, 0,                            0,                                    0,                                    FALSE },  //  EFI_SMM_SAVE_STATE_REGISTER_LDTINFO  = 10

+

+  { 4, 4, SMM_CPU_OFFSET (x86._ES),     SMM_CPU_OFFSET (x64._ES),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_ES       = 20

+  { 4, 4, SMM_CPU_OFFSET (x86._CS),     SMM_CPU_OFFSET (x64._CS),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_CS       = 21

+  { 4, 4, SMM_CPU_OFFSET (x86._SS),     SMM_CPU_OFFSET (x64._SS),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_SS       = 22

+  { 4, 4, SMM_CPU_OFFSET (x86._DS),     SMM_CPU_OFFSET (x64._DS),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_DS       = 23

+  { 4, 4, SMM_CPU_OFFSET (x86._FS),     SMM_CPU_OFFSET (x64._FS),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_FS       = 24

+  { 4, 4, SMM_CPU_OFFSET (x86._GS),     SMM_CPU_OFFSET (x64._GS),             0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_GS       = 25

+  { 0, 4, 0,                            SMM_CPU_OFFSET (x64.LdtrSelector),    0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_LDTR_SEL = 26

+  { 4, 4, SMM_CPU_OFFSET (x86._TR),     SMM_CPU_OFFSET (x64.TrSelector),      0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_TR_SEL   = 27

+  { 4, 8, SMM_CPU_OFFSET (x86._DR7),    SMM_CPU_OFFSET (x64._DR7),            SMM_CPU_OFFSET (x64._DR7)    + 4,     FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_DR7      = 28

+  { 4, 8, SMM_CPU_OFFSET (x86._DR6),    SMM_CPU_OFFSET (x64._DR6),            SMM_CPU_OFFSET (x64._DR6)    + 4,     FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_DR6      = 29

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R8),             SMM_CPU_OFFSET (x64._R8)     + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R8       = 30

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R9),             SMM_CPU_OFFSET (x64._R9)     + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R9       = 31

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R10),            SMM_CPU_OFFSET (x64._R10)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R10      = 32

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R11),            SMM_CPU_OFFSET (x64._R11)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R11      = 33

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R12),            SMM_CPU_OFFSET (x64._R12)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R12      = 34

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R13),            SMM_CPU_OFFSET (x64._R13)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R13      = 35

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R14),            SMM_CPU_OFFSET (x64._R14)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R14      = 36

+  { 0, 8, 0,                            SMM_CPU_OFFSET (x64._R15),            SMM_CPU_OFFSET (x64._R15)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_R15      = 37

+  { 4, 8, SMM_CPU_OFFSET (x86._EAX),    SMM_CPU_OFFSET (x64._RAX),            SMM_CPU_OFFSET (x64._RAX)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RAX      = 38

+  { 4, 8, SMM_CPU_OFFSET (x86._EBX),    SMM_CPU_OFFSET (x64._RBX),            SMM_CPU_OFFSET (x64._RBX)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RBX      = 39

+  { 4, 8, SMM_CPU_OFFSET (x86._ECX),    SMM_CPU_OFFSET (x64._RCX),            SMM_CPU_OFFSET (x64._RCX)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RCX      = 40

+  { 4, 8, SMM_CPU_OFFSET (x86._EDX),    SMM_CPU_OFFSET (x64._RDX),            SMM_CPU_OFFSET (x64._RDX)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RDX      = 41

+  { 4, 8, SMM_CPU_OFFSET (x86._ESP),    SMM_CPU_OFFSET (x64._RSP),            SMM_CPU_OFFSET (x64._RSP)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RSP      = 42

+  { 4, 8, SMM_CPU_OFFSET (x86._EBP),    SMM_CPU_OFFSET (x64._RBP),            SMM_CPU_OFFSET (x64._RBP)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RBP      = 43

+  { 4, 8, SMM_CPU_OFFSET (x86._ESI),    SMM_CPU_OFFSET (x64._RSI),            SMM_CPU_OFFSET (x64._RSI)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RSI      = 44

+  { 4, 8, SMM_CPU_OFFSET (x86._EDI),    SMM_CPU_OFFSET (x64._RDI),            SMM_CPU_OFFSET (x64._RDI)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RDI      = 45

+  { 4, 8, SMM_CPU_OFFSET (x86._EIP),    SMM_CPU_OFFSET (x64._RIP),            SMM_CPU_OFFSET (x64._RIP)    + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RIP      = 46

+

+  { 4, 8, SMM_CPU_OFFSET (x86._EFLAGS), SMM_CPU_OFFSET (x64._RFLAGS),         SMM_CPU_OFFSET (x64._RFLAGS) + 4,     TRUE  }, //  EFI_SMM_SAVE_STATE_REGISTER_RFLAGS   = 51

+  { 4, 8, SMM_CPU_OFFSET (x86._CR0),    SMM_CPU_OFFSET (x64._CR0),            SMM_CPU_OFFSET (x64._CR0)    + 4,     FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_CR0      = 52

+  { 4, 8, SMM_CPU_OFFSET (x86._CR3),    SMM_CPU_OFFSET (x64._CR3),            SMM_CPU_OFFSET (x64._CR3)    + 4,     FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_CR3      = 53

+  { 0, 4, 0,                            SMM_CPU_OFFSET (x64._CR4),            0,                                    FALSE }, //  EFI_SMM_SAVE_STATE_REGISTER_CR4      = 54

+};

+

+///

+/// Lookup table for the IOMisc width information

+///

+CONST CPU_SMM_SAVE_STATE_IO_WIDTH  mSmmCpuIoWidth[] = {

+  { 0, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  },  // Undefined           = 0

+  { 1, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  },  // SMM_IO_LENGTH_BYTE  = 1

+  { 2, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT16 },  // SMM_IO_LENGTH_WORD  = 2

+  { 0, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  },  // Undefined           = 3

+  { 4, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT32 },  // SMM_IO_LENGTH_DWORD = 4

+  { 0, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  },  // Undefined           = 5

+  { 0, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  },  // Undefined           = 6

+  { 0, EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8  }   // Undefined           = 7

+};

+

+///

+/// Lookup table for the IOMisc type information

+///

+CONST EFI_SMM_SAVE_STATE_IO_TYPE  mSmmCpuIoType[] = {

+  EFI_SMM_SAVE_STATE_IO_TYPE_OUTPUT,     // SMM_IO_TYPE_OUT_DX        = 0

+  EFI_SMM_SAVE_STATE_IO_TYPE_INPUT,      // SMM_IO_TYPE_IN_DX         = 1

+  EFI_SMM_SAVE_STATE_IO_TYPE_STRING,     // SMM_IO_TYPE_OUTS          = 2

+  EFI_SMM_SAVE_STATE_IO_TYPE_STRING,     // SMM_IO_TYPE_INS           = 3

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 4

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 5

+  EFI_SMM_SAVE_STATE_IO_TYPE_REP_PREFIX, // SMM_IO_TYPE_REP_OUTS      = 6

+  EFI_SMM_SAVE_STATE_IO_TYPE_REP_PREFIX, // SMM_IO_TYPE_REP_INS       = 7

+  EFI_SMM_SAVE_STATE_IO_TYPE_OUTPUT,     // SMM_IO_TYPE_OUT_IMMEDIATE = 8

+  EFI_SMM_SAVE_STATE_IO_TYPE_INPUT,      // SMM_IO_TYPE_OUT_IMMEDIATE = 9

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 10

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 11

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 12

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 13

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0,         // Undefined                 = 14

+  (EFI_SMM_SAVE_STATE_IO_TYPE)0          // Undefined                 = 15

+};

+

+///

+/// The mode of the CPU at the time an SMI occurs

+///

+UINT8  mSmmSaveStateRegisterLma;

+

+/**

+  Read information from the CPU save state.

+

+  @param  Register  Specifies the CPU register to read form the save state.

+

+  @retval 0   Register is not valid

+  @retval >0  Index into mSmmCpuWidthOffset[] associated with Register

+

+**/

+UINTN

+GetRegisterIndex (

+  IN EFI_SMM_SAVE_STATE_REGISTER  Register

+  )

+{

+  UINTN  Index;

+  UINTN  Offset;

+

+  for (Index = 0, Offset = SMM_SAVE_STATE_REGISTER_MAX_INDEX; mSmmCpuRegisterRanges[Index].Length != 0; Index++) {

+    if ((Register >= mSmmCpuRegisterRanges[Index].Start) && (Register <= mSmmCpuRegisterRanges[Index].End)) {

+      return Register - mSmmCpuRegisterRanges[Index].Start + Offset;

+    }

+

+    Offset += mSmmCpuRegisterRanges[Index].Length;

+  }

+

+  return 0;

+}

+

+/**

+  Read a CPU Save State register on the target processor.

+

+  This function abstracts the differences that whether the CPU Save State register is in the

+  IA32 CPU Save State Map or X64 CPU Save State Map.

+

+  This function supports reading a CPU Save State register in SMBase relocation handler.

+

+  @param[in]  CpuIndex       Specifies the zero-based index of the CPU save state.

+  @param[in]  RegisterIndex  Index into mSmmCpuWidthOffset[] look up table.

+  @param[in]  Width          The number of bytes to read from the CPU save state.

+  @param[out] Buffer         Upon return, this holds the CPU register value read from the save state.

+

+  @retval EFI_SUCCESS           The register was read from Save State.

+  @retval EFI_NOT_FOUND         The register is not defined for the Save State of Processor.

+  @retval EFI_INVALID_PARAMETER  This or Buffer is NULL.

+

+**/

+EFI_STATUS

+ReadSaveStateRegisterByIndex (

+  IN UINTN  CpuIndex,

+  IN UINTN  RegisterIndex,

+  IN UINTN  Width,

+  OUT VOID  *Buffer

+  )

+{

+  SMRAM_SAVE_STATE_MAP  *CpuSaveState;

+

+  if (RegisterIndex == 0) {

+    return EFI_NOT_FOUND;

+  }

+

+  CpuSaveState = gSmst->CpuSaveState[CpuIndex];

+

+  if (mSmmSaveStateRegisterLma == EFI_SMM_SAVE_STATE_REGISTER_LMA_32BIT) {

+    //

+    // If 32-bit mode width is zero, then the specified register can not be accessed

+    //

+    if (mSmmCpuWidthOffset[RegisterIndex].Width32 == 0) {

+      return EFI_NOT_FOUND;

+    }

+

+    //

+    // If Width is bigger than the 32-bit mode width, then the specified register can not be accessed

+    //

+    if (Width > mSmmCpuWidthOffset[RegisterIndex].Width32) {

+      return EFI_INVALID_PARAMETER;

+    }

+

+    //

+    // Write return buffer

+    //

+    ASSERT (CpuSaveState != NULL);

+    CopyMem (Buffer, (UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset32, Width);

+  } else {

+    //

+    // If 64-bit mode width is zero, then the specified register can not be accessed

+    //

+    if (mSmmCpuWidthOffset[RegisterIndex].Width64 == 0) {

+      return EFI_NOT_FOUND;

+    }

+

+    //

+    // If Width is bigger than the 64-bit mode width, then the specified register can not be accessed

+    //

+    if (Width > mSmmCpuWidthOffset[RegisterIndex].Width64) {

+      return EFI_INVALID_PARAMETER;

+    }

+

+    //

+    // Write at most 4 of the lower bytes of the return buffer

+    //

+    CopyMem (Buffer, (UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset64Lo, MIN (4, Width));

+    if (Width > 4) {

+      //

+      // Write at most 4 of the upper bytes of the return buffer

+      //

+      CopyMem ((UINT8 *)Buffer + 4, (UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset64Hi, Width - 4);

+    }

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Read a CPU Save State register on the target processor.

+

+  This function abstracts the differences that whether the CPU Save State register is in the

+  IA32 CPU Save State Map or X64 CPU Save State Map.

+

+  This function supports reading a CPU Save State register in SMBase relocation handler.

+

+  @param[in]  CpuIndex       Specifies the zero-based index of the CPU save state.

+  @param[in]  RegisterIndex  Index into mSmmCpuWidthOffset[] look up table.

+  @param[in]  Width          The number of bytes to read from the CPU save state.

+  @param[out] Buffer         Upon return, this holds the CPU register value read from the save state.

+

+  @retval EFI_SUCCESS           The register was read from Save State.

+  @retval EFI_NOT_FOUND         The register is not defined for the Save State of Processor.

+  @retval EFI_INVALID_PARAMETER Buffer is NULL, or Width does not meet requirement per Register type.

+

+**/

+EFI_STATUS

+EFIAPI

+ReadSaveStateRegister (

+  IN UINTN                        CpuIndex,

+  IN EFI_SMM_SAVE_STATE_REGISTER  Register,

+  IN UINTN                        Width,

+  OUT VOID                        *Buffer

+  )

+{

+  SMRAM_SAVE_STATE_MAP        *CpuSaveState;

+  EFI_SMM_SAVE_STATE_IO_INFO  *IoInfo;

+

+  CpuSaveState = gSmst->CpuSaveState[CpuIndex];

+  //

+  // Check for special EFI_SMM_SAVE_STATE_REGISTER_LMA

+  //

+  if (Register == EFI_SMM_SAVE_STATE_REGISTER_LMA) {

+    //

+    // Only byte access is supported for this register

+    //

+    if (Width != 1) {

+      return EFI_INVALID_PARAMETER;

+    }

+

+    *(UINT8 *)Buffer = mSmmSaveStateRegisterLma;

+

+    return EFI_SUCCESS;

+  }

+

+  //

+  // Check for special EFI_SMM_SAVE_STATE_REGISTER_IO

+  //

+  if (Register == EFI_SMM_SAVE_STATE_REGISTER_IO) {

+    //

+    // Check SMM IO Trap Offset valid bit

+    //

+    if (!(CpuSaveState->x64.SMM_IO_TRAP & 0x02)) {

+      return EFI_NOT_FOUND;

+    }

+

+    //

+    // Zero the IoInfo structure that will be returned in Buffer

+    //

+    IoInfo = (EFI_SMM_SAVE_STATE_IO_INFO *)Buffer;

+    ZeroMem (IoInfo, sizeof (EFI_SMM_SAVE_STATE_IO_INFO));

+

+    //

+    // Use hard code to fill in all the fields of the IoInfo structure

+    //

+    IoInfo->IoPort  = (UINT16)(CpuSaveState->x64.SMM_IO_TRAP >> 16);

+    IoInfo->IoWidth = EFI_SMM_SAVE_STATE_IO_WIDTH_UINT8;

+    IoInfo->IoType  = EFI_SMM_SAVE_STATE_IO_TYPE_INPUT;

+    IoInfo->IoData  = (UINT64)IoRead8 ((CpuSaveState->x64.SMM_IO_TRAP >> 16));

+

+    return EFI_SUCCESS;

+  }

+

+  //

+  // Convert Register to a register lookup table index

+  //

+  return ReadSaveStateRegisterByIndex (CpuIndex, GetRegisterIndex (Register), Width, Buffer);

+}

+

+/**

+  Write value to a CPU Save State register on the target processor.

+

+  This function abstracts the differences that whether the CPU Save State register is in the

+  IA32 CPU Save State Map or X64 CPU Save State Map.

+

+  This function supports writing a CPU Save State register in SMBase relocation handler.

+

+  @param[in] CpuIndex       Specifies the zero-based index of the CPU save state.

+  @param[in] RegisterIndex  Index into mSmmCpuWidthOffset[] look up table.

+  @param[in] Width          The number of bytes to read from the CPU save state.

+  @param[in] Buffer         Upon entry, this holds the new CPU register value.

+

+  @retval EFI_SUCCESS           The register was written to Save State.

+  @retval EFI_NOT_FOUND         The register is not defined for the Save State of Processor.

+  @retval EFI_INVALID_PARAMETER  ProcessorIndex or Width is not correct.

+

+**/

+EFI_STATUS

+EFIAPI

+WriteSaveStateRegister (

+  IN UINTN                        CpuIndex,

+  IN EFI_SMM_SAVE_STATE_REGISTER  Register,

+  IN UINTN                        Width,

+  IN CONST VOID                   *Buffer

+  )

+{

+  UINTN                 RegisterIndex;

+  SMRAM_SAVE_STATE_MAP  *CpuSaveState;

+

+  //

+  // Writes to EFI_SMM_SAVE_STATE_REGISTER_LMA are ignored

+  //

+  if (Register == EFI_SMM_SAVE_STATE_REGISTER_LMA) {

+    return EFI_SUCCESS;

+  }

+

+  //

+  // Writes to EFI_SMM_SAVE_STATE_REGISTER_IO are not supported

+  //

+  if (Register == EFI_SMM_SAVE_STATE_REGISTER_IO) {

+    return EFI_NOT_FOUND;

+  }

+

+  //

+  // Convert Register to a register lookup table index

+  //

+  RegisterIndex = GetRegisterIndex (Register);

+  if (RegisterIndex == 0) {

+    return EFI_NOT_FOUND;

+  }

+

+  CpuSaveState = gSmst->CpuSaveState[CpuIndex];

+

+  //

+  // Do not write non-writable SaveState, because it will cause exception.

+  //

+  if (!mSmmCpuWidthOffset[RegisterIndex].Writeable) {

+    return EFI_UNSUPPORTED;

+  }

+

+  //

+  // Check CPU mode

+  //

+  if (mSmmSaveStateRegisterLma == EFI_SMM_SAVE_STATE_REGISTER_LMA_32BIT) {

+    //

+    // If 32-bit mode width is zero, then the specified register can not be accessed

+    //

+    if (mSmmCpuWidthOffset[RegisterIndex].Width32 == 0) {

+      return EFI_NOT_FOUND;

+    }

+

+    //

+    // If Width is bigger than the 32-bit mode width, then the specified register can not be accessed

+    //

+    if (Width > mSmmCpuWidthOffset[RegisterIndex].Width32) {

+      return EFI_INVALID_PARAMETER;

+    }

+

+    //

+    // Write SMM State register

+    //

+    ASSERT (CpuSaveState != NULL);

+    CopyMem ((UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset32, Buffer, Width);

+  } else {

+    //

+    // If 64-bit mode width is zero, then the specified register can not be accessed

+    //

+    if (mSmmCpuWidthOffset[RegisterIndex].Width64 == 0) {

+      return EFI_NOT_FOUND;

+    }

+

+    //

+    // If Width is bigger than the 64-bit mode width, then the specified register can not be accessed

+    //

+    if (Width > mSmmCpuWidthOffset[RegisterIndex].Width64) {

+      return EFI_INVALID_PARAMETER;

+    }

+

+    //

+    // Write at most 4 of the lower bytes of SMM State register

+    //

+    CopyMem ((UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset64Lo, Buffer, MIN (4, Width));

+    if (Width > 4) {

+      //

+      // Write at most 4 of the upper bytes of SMM State register

+      //

+      CopyMem ((UINT8 *)CpuSaveState + mSmmCpuWidthOffset[RegisterIndex].Offset64Hi, (UINT8 *)Buffer + 4, Width - 4);

+    }

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Hook the code executed immediately after an RSM instruction on the currently

+  executing CPU.  The mode of code executed immediately after RSM must be

+  detected, and the appropriate hook must be selected.  Always clear the auto

+  HALT restart flag if it is set.

+

+  @param[in] CpuIndex                 The processor index for the currently

+                                      executing CPU.

+  @param[in] CpuState                 Pointer to SMRAM Save State Map for the

+                                      currently executing CPU.

+  @param[in] NewInstructionPointer32  Instruction pointer to use if resuming to

+                                      32-bit mode from 64-bit SMM.

+  @param[in] NewInstructionPointer    Instruction pointer to use if resuming to

+                                      same mode as SMM.

+

+  @retval The value of the original instruction pointer before it was hooked.

+

+**/

+UINT64

+EFIAPI

+HookReturnFromSmm (

+  IN UINTN              CpuIndex,

+  SMRAM_SAVE_STATE_MAP  *CpuState,

+  UINT64                NewInstructionPointer32,

+  UINT64                NewInstructionPointer

+  )

+{

+  UINT64  OriginalInstructionPointer;

+

+  OriginalInstructionPointer = SmmCpuFeaturesHookReturnFromSmm (

+                                 CpuIndex,

+                                 CpuState,

+                                 NewInstructionPointer32,

+                                 NewInstructionPointer

+                                 );

+  if (OriginalInstructionPointer != 0) {

+    return OriginalInstructionPointer;

+  }

+

+  if (mSmmSaveStateRegisterLma == EFI_SMM_SAVE_STATE_REGISTER_LMA_32BIT) {

+    OriginalInstructionPointer = (UINT64)CpuState->x86._EIP;

+    CpuState->x86._EIP         = (UINT32)NewInstructionPointer;

+    //

+    // Clear the auto HALT restart flag so the RSM instruction returns

+    // program control to the instruction following the HLT instruction.

+    //

+    if ((CpuState->x86.AutoHALTRestart & BIT0) != 0) {

+      CpuState->x86.AutoHALTRestart &= ~BIT0;

+    }

+  } else {

+    OriginalInstructionPointer = CpuState->x64._RIP;

+    if ((CpuState->x64.EFER & LMA) == 0) {

+      CpuState->x64._RIP = (UINT32)NewInstructionPointer32;

+    } else {

+      CpuState->x64._RIP = (UINT32)NewInstructionPointer;

+    }

+

+    //

+    // Clear the auto HALT restart flag so the RSM instruction returns

+    // program control to the instruction following the HLT instruction.

+    //

+    if ((CpuState->x64.AutoHALTRestart & BIT0) != 0) {

+      CpuState->x64.AutoHALTRestart &= ~BIT0;

+    }

+  }

+

+  return OriginalInstructionPointer;

+}

+

+/**

+  Get the size of the SMI Handler in bytes.

+

+  @retval The size, in bytes, of the SMI Handler.

+

+**/

+UINTN

+EFIAPI

+GetSmiHandlerSize (

+  VOID

+  )

+{

+  UINTN  Size;

+

+  Size = SmmCpuFeaturesGetSmiHandlerSize ();

+  if (Size != 0) {

+    return Size;

+  }

+

+  return gcSmiHandlerSize;

+}

+

+/**

+  Install the SMI handler for the CPU specified by CpuIndex.  This function

+  is called by the CPU that was elected as monarch during System Management

+  Mode initialization.

+

+  @param[in] CpuIndex   The index of the CPU to install the custom SMI handler.

+                        The value must be between 0 and the NumberOfCpus field

+                        in the System Management System Table (SMST).

+  @param[in] SmBase     The SMBASE address for the CPU specified by CpuIndex.

+  @param[in] SmiStack   The stack to use when an SMI is processed by the

+                        the CPU specified by CpuIndex.

+  @param[in] StackSize  The size, in bytes, if the stack used when an SMI is

+                        processed by the CPU specified by CpuIndex.

+  @param[in] GdtBase    The base address of the GDT to use when an SMI is

+                        processed by the CPU specified by CpuIndex.

+  @param[in] GdtSize    The size, in bytes, of the GDT used when an SMI is

+                        processed by the CPU specified by CpuIndex.

+  @param[in] IdtBase    The base address of the IDT to use when an SMI is

+                        processed by the CPU specified by CpuIndex.

+  @param[in] IdtSize    The size, in bytes, of the IDT used when an SMI is

+                        processed by the CPU specified by CpuIndex.

+  @param[in] Cr3        The base address of the page tables to use when an SMI

+                        is processed by the CPU specified by CpuIndex.

+**/

+VOID

+EFIAPI

+InstallSmiHandler (

+  IN UINTN   CpuIndex,

+  IN UINT32  SmBase,

+  IN VOID    *SmiStack,

+  IN UINTN   StackSize,

+  IN UINTN   GdtBase,

+  IN UINTN   GdtSize,

+  IN UINTN   IdtBase,

+  IN UINTN   IdtSize,

+  IN UINT32  Cr3

+  )

+{

+  PROCESSOR_SMM_DESCRIPTOR  *Psd;

+  UINT32                    CpuSmiStack;

+

+  //

+  // Initialize PROCESSOR_SMM_DESCRIPTOR

+  //

+  Psd = (PROCESSOR_SMM_DESCRIPTOR *)(VOID *)((UINTN)SmBase + SMM_PSD_OFFSET);

+  CopyMem (Psd, &gcPsd, sizeof (gcPsd));

+  Psd->SmmGdtPtr  = (UINT64)GdtBase;

+  Psd->SmmGdtSize = (UINT32)GdtSize;

+

+  if (SmmCpuFeaturesGetSmiHandlerSize () != 0) {

+    //

+    // Install SMI handler provided by library

+    //

+    SmmCpuFeaturesInstallSmiHandler (

+      CpuIndex,

+      SmBase,

+      SmiStack,

+      StackSize,

+      GdtBase,

+      GdtSize,

+      IdtBase,

+      IdtSize,

+      Cr3

+      );

+    return;

+  }

+

+  InitShadowStack (CpuIndex, (VOID *)((UINTN)SmiStack + StackSize));

+

+  //

+  // Initialize values in template before copy

+  //

+  CpuSmiStack = (UINT32)((UINTN)SmiStack + StackSize - sizeof (UINTN));

+  PatchInstructionX86 (gPatchSmiStack, CpuSmiStack, 4);

+  PatchInstructionX86 (gPatchSmiCr3, Cr3, 4);

+  PatchInstructionX86 (gPatchSmbase, SmBase, 4);

+  gSmiHandlerIdtr.Base  = IdtBase;

+  gSmiHandlerIdtr.Limit = (UINT16)(IdtSize - 1);

+

+  //

+  // Set the value at the top of the CPU stack to the CPU Index

+  //

+  *(UINTN *)(UINTN)CpuSmiStack = CpuIndex;

+

+  //

+  // Copy template to CPU specific SMI handler location

+  //

+  CopyMem (

+    (VOID *)((UINTN)SmBase + SMM_HANDLER_OFFSET),

+    (VOID *)gcSmiHandlerTemplate,

+    gcSmiHandlerSize

+    );

+}

--

2.31.1










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  reply	other threads:[~2024-01-20 14:37 UTC|newest]

Thread overview: 49+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-18  6:50 [edk2-devel] [PATCH 00/33] Introduce AMD Vangogh platform reference code duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 01/33] AMD/AmdPlatformPkg: Check in AMD S3 logo duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 02/33] AMD/VanGoghBoard: Check in ACPI tables duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 03/33] AMD/VanGoghBoard: Check in Capsule update duke.zhai via groups.io
2024-01-23  4:42   ` Chang, Abner via groups.io
2024-01-25  8:25     ` Zhai, MingXin (Duke) via groups.io
2024-01-25 11:45       ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 04/33] AMD/VanGoghBoard: Check in AgesaPublic pkg duke.zhai via groups.io
2024-01-23  4:44   ` Chang, Abner via groups.io
2024-01-25  8:17     ` Xing, Eric via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 05/33] AMD/VanGoghBoard: Check in PlatformSecLib duke.zhai via groups.io
2024-01-23  4:46   ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 06/33] AMD/VanGoghBoard: Check in AmdIdsExtLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 07/33] AMD/VanGoghBoard: Check in PciPlatform duke.zhai via groups.io
2024-01-23  4:50   ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 08/33] AMD/VanGoghBoard: Check in UDKFlashUpdate duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 09/33] AMD/VanGoghBoard: Check in Flash_AB duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 10/33] AMD/VanGoghBoard: Check in FlashUpdate duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 11/33] AMD/VanGoghBoard: Check in FvbServices duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 12/33] AMD/VanGoghBoard: Check in AMD BaseSerialPortLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 13/33] AMD/VanGoghBoard: Check in PlatformFlashAccessLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 14/33] AMD/VanGoghBoard: Check in SmbiosLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 15/33] AMD/VanGoghBoard: Check in SpiFlashDeviceLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 16/33] AMD/VanGoghBoard: Check in BaseTscTimerLib duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 17/33] AMD/VanGoghBoard: Check in Smm access module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 18/33] AMD/VanGoghBoard: Check in PciHostBridge module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 19/33] AMD/VanGoghBoard: Check in PcatRealTimeClockRuntimeDxe module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 20/33] AMD/VanGoghBoard: Check in FTPM module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 21/33] AMD/VanGoghBoard: Check in SignedCapsule duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 22/33] AMD/VanGoghBoard: Check in Vtf0 duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 23/33] AMD/VanGoghBoard: Check in AcpiPlatform duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 24/33] AMD/VanGoghBoard: Check in FchSpi module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 25/33] AMD/VanGoghBoard: Check in PlatformInitPei module duke.zhai via groups.io
2024-01-23  6:35   ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 26/33] AMD/VanGoghBoard: Check in Smbios platform dxe drivers duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 27/33] AMD/VanGoghBoard: Check in Fsp2WrapperPkg duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 28/33] AMD/VanGoghBoard: Check in SmmCpuFeaturesLibCommon module duke.zhai via groups.io
2024-01-23  5:14   ` Chang, Abner via groups.io
2024-01-23 10:20     ` Xing, Eric via groups.io
2024-01-23 10:44       ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 29/33] AMD/VanGoghBoard: Check in SmramSaveState module duke.zhai via groups.io
2024-01-20 14:37   ` Abdul Lateef Attar via groups.io [this message]
2024-01-23  5:15     ` Chang, Abner via groups.io
2024-01-23 10:27       ` Xing, Eric via groups.io
2024-01-23 10:44         ` Chang, Abner via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 30/33] AMD/VanGoghBoard: Check in EDK2 override files duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 31/33] AMD/VanGoghBoard: Check in AMD SmmControlPei module duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 32/33] AMD/VanGoghBoard: Check in Chachani board project files and build script duke.zhai via groups.io
2024-01-18  6:50 ` [edk2-devel] [PATCH 33/33] AMD/VanGoghBoard: Improvement coding style duke.zhai via groups.io

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