ShellPkg/AcpiView: PCCT Parser

Bugzilla: 3047 (https://bugzilla.tianocore.org/show_bug.cgi?id=3047)

Create a new parser for the PCCT Table.

The PCCT Table is used to describe how the OSPM can
communicate with entities outside the platform. It
describes which memory spaces correspond to which
entity as well as a few of the needed information
to handle the communications.

This new PCCT parser dumps the values and names of
the table fields. It also performs some validation
on the table's fields.

Signed-off-by: Marc Moisson-Franckhauser <marc.moisson-franckhauser@arm.com>
Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Zhichao Gao <zhichao.gao@intel.com>

6 files changed, 679 insertions, 5 deletions

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
index f81ccac7e1..051fdf807a 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
@@ -1,7 +1,7 @@
 /** @file

   Header file for ACPI parser

 

-  Copyright (c) 2016 - 2020, ARM Limited. All rights reserved.

+  Copyright (c) 2016 - 2020, Arm Limited. All rights reserved.

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

 **/

 

@@ -671,6 +671,28 @@ ParseAcpiMcfg (
   );

 

 /**

+  This function parses the ACPI PCCT table including its sub-structures

+  of type 0 through 4.

+  When trace is enabled this function parses the PCCT table and

+  traces the ACPI table fields.

+

+  This function also performs validation of the ACPI table fields.

+

+  @param [in] Trace              If TRUE, trace the ACPI fields.

+  @param [in] Ptr                Pointer to the start of the buffer.

+  @param [in] AcpiTableLength    Length of the ACPI table.

+  @param [in] AcpiTableRevision  Revision of the ACPI table.

+**/

+VOID

+EFIAPI

+ParseAcpiPcct (

+  IN BOOLEAN Trace,

+  IN UINT8*  Ptr,

+  IN UINT32  AcpiTableLength,

+  IN UINT8   AcpiTableRevision

+  );

+

+/**

   This function parses the ACPI PPTT table.

   When trace is enabled this function parses the PPTT table and

   traces the ACPI table fields.

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiTableParser.h b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiTableParser.h
index 4f92596b90..0ebf79fb65 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiTableParser.h
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiTableParser.h
@@ -1,7 +1,7 @@
 /** @file

   Header file for ACPI table parser

 

-  Copyright (c) 2016 - 2018, ARM Limited. All rights reserved.

+  Copyright (c) 2016 - 2020, Arm Limited. All rights reserved.

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

 **/

 

@@ -11,7 +11,7 @@
 /**

   The maximum number of ACPI table parsers.

 */

-#define MAX_ACPI_TABLE_PARSERS          16

+#define MAX_ACPI_TABLE_PARSERS          32

 

 /** An invalid/NULL signature value.

 */

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.c
new file mode 100644
index 0000000000..ca553d5953
--- /dev/null
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.c
@@ -0,0 +1,615 @@
+/** @file

+  PCCT table parser

+

+  Copyright (c) 2020, Arm Limited.

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

+

+  @par Reference(s):

+    - ACPI 6.3 Specification - January 2019

+**/

+

+#include <Library/BaseMemoryLib.h>

+#include <Library/PrintLib.h>

+#include <Library/UefiLib.h>

+#include "AcpiParser.h"

+#include "AcpiView.h"

+#include "AcpiViewConfig.h"

+#include "PcctParser.h"

+

+// Local variables

+STATIC ACPI_DESCRIPTION_HEADER_INFO AcpiHdrInfo;

+

+STATIC UINT32* PccGlobalFlags;

+STATIC UINT8*  PccSubspaceLength;

+STATIC UINT8*  PccSubspaceType;

+STATIC UINT8*  ExtendedPccSubspaceInterruptFlags;

+

+/**

+  This function validates the length coded on 4 bytes of a shared memory range

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidateRangeLength4 (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  if (*(UINT32*)Ptr < MIN_EXT_PCC_SUBSPACE_MEM_RANGE_LEN) {

+    IncrementErrorCount ();

+    Print (

+      L"\nError: Shared memory range length is too short.\n"

+      L"Length is %u when it should be greater than or equal to %u",

+      *(UINT32*)Ptr,

+      MIN_EXT_PCC_SUBSPACE_MEM_RANGE_LEN

+      );

+  }

+}

+

+/**

+  This function validates the length coded on 8 bytes of a shared memory range

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidateRangeLength8 (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  if (*(UINT64*)Ptr <= MIN_MEMORY_RANGE_LENGTH) {

+    IncrementErrorCount ();

+    Print (

+      L"\nError: Shared memory range length is too short.\n"

+      L"Length is %u when it should be greater than %u",

+      *(UINT64*)Ptr,

+      MIN_MEMORY_RANGE_LENGTH

+      );

+  }

+}

+

+/**

+  This function validates address space for type 0 structure.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePccType0Gas (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  switch (*(UINT8*)Ptr) {

+#if !(defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64))

+    case EFI_ACPI_6_3_SYSTEM_IO:

+#endif //if not (defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64))

+    case EFI_ACPI_6_3_SYSTEM_MEMORY:

+      return;

+    default:

+      IncrementErrorCount ();

+      Print (L"\nError: Invalid address space");

+  }

+}

+

+/**

+  This function validates address space for structures of types other than 0.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePccGas (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  switch (*(UINT8*)Ptr) {

+#if !(defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64))

+    case EFI_ACPI_6_3_SYSTEM_IO:

+#endif //if not (defined (MDE_CPU_ARM) || defined (MDE_CPU_AARCH64))

+    case EFI_ACPI_6_3_FUNCTIONAL_FIXED_HARDWARE:

+    case EFI_ACPI_6_3_SYSTEM_MEMORY:

+      return;

+    default:

+      IncrementErrorCount ();

+      Print (L"\nError: Invalid address space");

+  }

+}

+

+/**

+  This function validates doorbell address space for type 4 structure.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePccDoorbellGas (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  // For slave subspaces this field is optional, if not present the field

+  // should just contain zeros.

+  if (*PccSubspaceType == EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_4_EXTENDED_PCC) {

+    if (IsZeroBuffer (

+          Ptr,

+          sizeof (EFI_ACPI_6_3_GENERIC_ADDRESS_STRUCTURE)

+          )) {

+      return;

+    }

+  }

+

+  ValidatePccGas (Ptr, Context);

+}

+

+/**

+  This function validates interrupt acknowledge address space for

+  type 4 structure.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePccIntAckGas (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  // If the subspace does not support interrupts or the interrupt is

+  // edge driven the register may be omitted. A value of 0x0 on all

+  // 12 bytes of the GAS structure indicates the register is not

+  // present.

+  if (((*PccGlobalFlags & EFI_ACPI_6_3_PCCT_FLAGS_PLATFORM_INTERRUPT) !=

+       EFI_ACPI_6_3_PCCT_FLAGS_PLATFORM_INTERRUPT) ||

+      ((*ExtendedPccSubspaceInterruptFlags &

+       EFI_ACPI_6_3_PCCT_SUBSPACE_PLATFORM_INTERRUPT_FLAGS_MODE) ==

+       EFI_ACPI_6_3_PCCT_SUBSPACE_PLATFORM_INTERRUPT_FLAGS_MODE)) {

+    if (IsZeroBuffer (

+          Ptr,

+          sizeof (EFI_ACPI_6_3_GENERIC_ADDRESS_STRUCTURE)

+          )) {

+      return;

+    }

+  }

+

+  ValidatePccGas (Ptr, Context);

+}

+

+/**

+  This function validates error status address space for type 4 structure.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePccErrStatusGas (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  // This field is ignored by the OSPM on slave channels.

+  if (*PccSubspaceType == EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_4_EXTENDED_PCC) {

+    return;

+  }

+

+  ValidatePccGas (Ptr, Context);

+}

+

+/**

+  This function validates platform interrupt flags for type 4 structure.

+

+  @param [in] Ptr     Pointer to the start of the field data.

+  @param [in] Context Pointer to context specific information e.g. this

+                      could be a pointer to the ACPI table header.

+**/

+STATIC

+VOID

+EFIAPI

+ValidatePlatInterrupt (

+  IN UINT8* Ptr,

+  IN VOID*  Context

+  )

+{

+  // If a slave subspace is present in the PCCT, then the global Platform

+  // Interrupt flag must be set to 1.

+  if ((*PccSubspaceType == EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_4_EXTENDED_PCC) &&

+      ((*PccGlobalFlags & EFI_ACPI_6_3_PCCT_FLAGS_PLATFORM_INTERRUPT) !=

+        EFI_ACPI_6_3_PCCT_FLAGS_PLATFORM_INTERRUPT)) {

+    IncrementErrorCount ();

+    Print (

+      L"\nError: Global Platform interrupt flag must be set to 1" \

+        L" if a PCC type 4 structure is present in PCCT."

+      );

+  }

+}

+

+/**

+  An ACPI_PARSER array describing the ACPI PCCT Table.

+*/

+STATIC CONST ACPI_PARSER PcctParser[] = {

+  PARSE_ACPI_HEADER (&AcpiHdrInfo),

+  {L"Flags", 4, 36, NULL, NULL, (VOID**)&PccGlobalFlags, NULL, NULL},

+  {L"Reserved", 8, 40, NULL, NULL, NULL, NULL, NULL}

+};

+

+/**

+  An ACPI_PARSER array describing the platform communications channel subspace

+  structure header.

+*/

+STATIC CONST ACPI_PARSER PccSubspaceHeaderParser[] = {

+  PCC_SUBSPACE_HEADER ()

+  // ... Type Specific Fields ...

+};

+

+/**

+  An ACPI_PARSER array describing the Generic Communications Subspace - Type 0

+*/

+STATIC CONST ACPI_PARSER PccSubspaceType0Parser[] = {

+  PCC_SUBSPACE_HEADER (),

+  {L"Reserved", 6, 2, L"%x %x %x %x %x %x", Dump6Chars, NULL, NULL, NULL},

+  {L"Base Address", 8, 8, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Memory Range Length", 8, 16, L"0x%lx", NULL, NULL, ValidateRangeLength8,

+    NULL},

+  {L"Doorbell Register", 12, 24, NULL, DumpGas, NULL, ValidatePccType0Gas,

+    NULL},

+  {L"Doorbell Preserve", 8, 36, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Doorbell Write", 8, 44, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Nominal Latency", 4, 52, L"%u", NULL, NULL, NULL, NULL},

+  {L"Maximum Periodic Access Rate", 4, 56, L"%u", NULL, NULL, NULL, NULL},

+  {L"Minimum Request Turnaround Time", 2, 60, L"%u", NULL, NULL, NULL, NULL}

+};

+

+/**

+  An ACPI_PARSER array describing the HW-Reduced Communications Subspace

+  - Type 1

+*/

+STATIC CONST ACPI_PARSER PccSubspaceType1Parser[] = {

+  PCC_SUBSPACE_HEADER (),

+  {L"Platform Interrupt", 4, 2, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Flags", 1, 6, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Reserved", 1, 7, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Base Address", 8, 8, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Memory Range Length", 8, 16, L"0x%lx", NULL, NULL, ValidateRangeLength8,

+    NULL},

+  {L"Doorbell Register", 12, 24, NULL, DumpGas, NULL,

+    ValidatePccGas, NULL},

+  {L"Doorbell Preserve", 8, 36, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Doorbell Write", 8, 44, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Nominal Latency", 4, 52, L"%u", NULL, NULL, NULL, NULL},

+  {L"Maximum Periodic Access Rate", 4, 56, L"%u", NULL, NULL, NULL, NULL},

+  {L"Minimum Request Turnaround Time", 2, 60, L"%u", NULL, NULL, NULL, NULL}

+};

+

+/**

+  An ACPI_PARSER array describing the HW-Reduced Communications Subspace

+  - Type 2

+*/

+STATIC CONST ACPI_PARSER PccSubspaceType2Parser[] = {

+  PCC_SUBSPACE_HEADER (),

+  {L"Platform Interrupt", 4, 2, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Flags", 1, 6, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Reserved", 1, 7, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Base Address", 8, 8, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Memory Range Length", 8, 16, L"0x%lx", NULL, NULL, ValidateRangeLength8,

+    NULL},

+  {L"Doorbell Register", 12, 24, NULL, DumpGas, NULL,

+    ValidatePccGas, NULL},

+  {L"Doorbell Preserve", 8, 36, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Doorbell Write", 8, 44, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Nominal Latency", 4, 52, L"%u", NULL, NULL, NULL, NULL},

+  {L"Maximum Periodic Access Rate", 4, 56, L"%u", NULL, NULL, NULL, NULL},

+  {L"Minimum Request Turnaround Time", 2, 60, L"%u", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Ack Register", 12, 62, NULL, DumpGas, NULL,

+    ValidatePccGas, NULL},

+  {L"Platform Interrupt Ack Preserve", 8, 74, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Ack Write", 8, 82, L"0x%lx", NULL, NULL,

+    NULL, NULL},

+};

+

+/**

+  An ACPI_PARSER array describing the Extended PCC Subspaces - Type 3/4

+*/

+STATIC CONST ACPI_PARSER PccSubspaceType3Parser[] = {

+  PCC_SUBSPACE_HEADER (),

+  {L"Platform Interrupt", 4, 2, L"0x%x", NULL, NULL,

+    ValidatePlatInterrupt, NULL},

+  {L"Platform Interrupt Flags", 1, 6, L"0x%x", NULL,

+    (VOID**)&ExtendedPccSubspaceInterruptFlags, NULL, NULL},

+  {L"Reserved", 1, 7, L"0x%x", NULL, NULL, NULL, NULL},

+  {L"Base Address", 8, 8, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Memory Range Length", 4, 16, L"0x%x", NULL, NULL, ValidateRangeLength4,

+    NULL},

+  {L"Doorbell Register", 12, 20, NULL, DumpGas, NULL,

+    ValidatePccDoorbellGas, NULL},

+  {L"Doorbell Preserve", 8, 32, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Doorbell Write", 8, 40, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Nominal Latency", 4, 48, L"%u", NULL, NULL, NULL, NULL},

+  {L"Maximum Periodic Access Rate", 4, 52, L"%u", NULL, NULL, NULL, NULL},

+  {L"Minimum Request Turnaround Time", 4, 56, L"%u", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Ack Register", 12, 60, NULL, DumpGas, NULL,

+    ValidatePccIntAckGas, NULL},

+  {L"Platform Interrupt Ack Preserve", 8, 72, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Platform Interrupt Ack Set", 8, 80, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Reserved", 8, 88, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Cmd Complete Check Reg Addr", 12, 96, NULL, DumpGas, NULL,

+    ValidatePccGas, NULL},

+  {L"Cmd Complete Check Mask", 8, 108, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Cmd Update Reg Addr", 12, 116, NULL, DumpGas, NULL,

+    ValidatePccGas, NULL},

+  {L"Cmd Update Preserve mask", 8, 128, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Cmd Update Set mask", 8, 136, L"0x%lx", NULL, NULL, NULL, NULL},

+  {L"Error Status Register", 12, 144, NULL, DumpGas, NULL,

+    ValidatePccErrStatusGas, NULL},

+  {L"Error Status Mask", 8, 156, L"0x%lx", NULL, NULL, NULL, NULL},

+};

+

+/**

+  This function parses the PCC Subspace type 0.

+

+  @param [in] Ptr     Pointer to the start of Subspace Structure.

+  @param [in] Length  Length of the Subspace Structure.

+**/

+STATIC

+VOID

+DumpPccSubspaceType0 (

+  IN UINT8* Ptr,

+  IN UINT8  Length

+  )

+{

+  ParseAcpi (

+    TRUE,

+    2,

+    "Subspace Type 0",

+    Ptr,

+    Length,

+    PARSER_PARAMS (PccSubspaceType0Parser)

+    );

+}

+

+/**

+  This function parses the PCC Subspace type 1.

+

+  @param [in] Ptr     Pointer to the start of the Subspace Structure.

+  @param [in] Length  Length of the Subspace Structure.

+**/

+STATIC

+VOID

+DumpPccSubspaceType1 (

+  IN UINT8* Ptr,

+  IN UINT8  Length

+  )

+{

+  ParseAcpi (

+    TRUE,

+    2,

+    "Subspace Type 1",

+    Ptr,

+    Length,

+    PARSER_PARAMS (PccSubspaceType1Parser)

+    );

+}

+

+/**

+  This function parses the PCC Subspace type 2.

+

+  @param [in] Ptr     Pointer to the start of the Subspace Structure.

+  @param [in] Length  Length of the Subspace Structure.

+**/

+STATIC

+VOID

+DumpPccSubspaceType2 (

+  IN UINT8* Ptr,

+  IN UINT8  Length

+  )

+{

+  ParseAcpi (

+    TRUE,

+    2,

+    "Subspace Type 2",

+    Ptr,

+    Length,

+    PARSER_PARAMS (PccSubspaceType2Parser)

+    );

+}

+

+/**

+  This function parses the PCC Subspace type 3.

+

+  @param [in] Ptr     Pointer to the start of the Subspace Structure.

+  @param [in] Length  Length of the Subspace Structure.

+**/

+STATIC

+VOID

+DumpPccSubspaceType3 (

+  IN UINT8* Ptr,

+  IN UINT8  Length

+  )

+{

+  ParseAcpi (

+    TRUE,

+    2,

+    "Subspace Type 3",

+    Ptr,

+    Length,

+    PARSER_PARAMS (PccSubspaceType3Parser)

+    );

+}

+

+/**

+  This function parses the PCC Subspace type 4.

+

+  @param [in] Ptr     Pointer to the start of the Subspace Structure.

+  @param [in] Length  Length of the Subspace Structure.

+**/

+STATIC

+VOID

+DumpPccSubspaceType4 (

+  IN UINT8* Ptr,

+  IN UINT8  Length

+  )

+{

+  ParseAcpi (

+    TRUE,

+    2,

+    "Subspace Type 4",

+    Ptr,

+    Length,

+    PARSER_PARAMS (PccSubspaceType3Parser)

+    );

+}

+

+/**

+  This function parses the ACPI PCCT table including its sub-structures

+  of type 0 through 4.

+  When trace is enabled this function parses the PCCT table and

+  traces the ACPI table fields.

+

+  This function also performs validation of the ACPI table fields.

+

+  @param [in] Trace              If TRUE, trace the ACPI fields.

+  @param [in] Ptr                Pointer to the start of the buffer.

+  @param [in] AcpiTableLength    Length of the ACPI table.

+  @param [in] AcpiTableRevision  Revision of the ACPI table.

+**/

+VOID

+EFIAPI

+ParseAcpiPcct (

+  IN BOOLEAN Trace,

+  IN UINT8*  Ptr,

+  IN UINT32  AcpiTableLength,

+  IN UINT8   AcpiTableRevision

+  )

+{

+  UINT32 Offset;

+  UINT8* PccSubspacePtr;

+  UINTN  SubspaceCount;

+

+  if (!Trace) {

+    return;

+  }

+

+  Offset = ParseAcpi (

+             TRUE,

+             0,

+             "PCCT",

+             Ptr,

+             AcpiTableLength,

+             PARSER_PARAMS (PcctParser)

+             );

+

+  PccSubspacePtr = Ptr + Offset;

+

+  SubspaceCount = 0;

+  while (Offset < AcpiTableLength) {

+    // Parse common structure header to obtain Type and Length.

+    ParseAcpi (

+      FALSE,

+      0,

+      NULL,

+      PccSubspacePtr,

+      AcpiTableLength - Offset,

+      PARSER_PARAMS (PccSubspaceHeaderParser)

+      );

+

+    // Check if the values used to control the parsing logic have been

+    // successfully read.

+    if ((PccSubspaceType == NULL) ||

+        (PccSubspaceLength == NULL)) {

+      IncrementErrorCount ();

+      Print (

+        L"ERROR: Insufficient remaining table buffer length to read the " \

+          L"structure header. Length = %u.\n",

+        AcpiTableLength - Offset

+        );

+      return;

+    }

+

+    // Validate Structure length

+    if ((*PccSubspaceLength == 0) ||

+        ((Offset + (*PccSubspaceLength)) > AcpiTableLength)) {

+      IncrementErrorCount ();

+      Print (

+        L"ERROR: Invalid Structure length. " \

+          L"Length = %u. Offset = %u. AcpiTableLength = %u.\n",

+        *PccSubspaceLength,

+        Offset,

+        AcpiTableLength

+        );

+      return;

+    }

+

+    switch (*PccSubspaceType) {

+      case EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_GENERIC:

+        DumpPccSubspaceType0 (

+          PccSubspacePtr,

+          *PccSubspaceLength

+          );

+        break;

+      case EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_1_HW_REDUCED_COMMUNICATIONS:

+        DumpPccSubspaceType1 (

+          PccSubspacePtr,

+          *PccSubspaceLength

+          );

+        break;

+      case EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_2_HW_REDUCED_COMMUNICATIONS:

+        DumpPccSubspaceType2 (

+          PccSubspacePtr,

+          *PccSubspaceLength

+          );

+        break;

+      case EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_3_EXTENDED_PCC:

+        DumpPccSubspaceType3 (

+          PccSubspacePtr,

+          *PccSubspaceLength

+          );

+        break;

+      case EFI_ACPI_6_3_PCCT_SUBSPACE_TYPE_4_EXTENDED_PCC:

+        DumpPccSubspaceType4 (

+          PccSubspacePtr,

+          *PccSubspaceLength

+          );

+        break;

+      default:

+        IncrementErrorCount ();

+        Print (

+          L"ERROR: Unknown PCC subspace structure:"

+            L" Type = %u, Length = %u\n",

+          PccSubspaceType,

+          *PccSubspaceLength

+          );

+    }

+

+    PccSubspacePtr += *PccSubspaceLength;

+    Offset += *PccSubspaceLength;

+    SubspaceCount++;

+  } // while

+

+  if (SubspaceCount > MAX_PCC_SUBSPACES) {

+    IncrementErrorCount ();

+    Print (L"ERROR: Too many PCC subspaces.");

+  }

+}

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.h b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.h
new file mode 100644
index 0000000000..278dc83c5d
--- /dev/null
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.h
@@ -0,0 +1,33 @@
+/** @file

+  Header file for PCCT parser

+

+  Copyright (c) 2020, Arm Limited.

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

+**/

+

+#ifndef PCCT_PARSER_H_

+#define PCCT_PARSER_H_

+

+/**

+  Minimum value for the 'length' field in subspaces of types 0, 1 and 2.

+*/

+#define MIN_MEMORY_RANGE_LENGTH                 8

+

+/**

+  Minimum value for the 'length' field in subspaces of types 3 and 4.

+*/

+#define MIN_EXT_PCC_SUBSPACE_MEM_RANGE_LEN      16

+

+/**

+  Maximum number of PCC subspaces.

+*/

+#define MAX_PCC_SUBSPACES                       256

+

+/**

+  Parser for the header of any type of PCC subspace.

+*/

+#define PCC_SUBSPACE_HEADER()                                             \

+  {L"Type", 1, 0, L"0x%x", NULL, (VOID**)&PccSubspaceType, NULL, NULL},   \

+  {L"Length", 1, 1, L"%u", NULL, (VOID**)&PccSubspaceLength, NULL, NULL}

+

+#endif // PCCT_PARSER_H_

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
index d2f26ff89f..feb80661cd 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.c
@@ -1,7 +1,7 @@
 /** @file

   Main file for 'acpiview' Shell command function.

 

-  Copyright (c) 2016 - 2020, ARM Limited. All rights reserved.<BR>

+  Copyright (c) 2016 - 2020, Arm Limited. All rights reserved.<BR>

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

 **/

 

@@ -57,6 +57,8 @@ ACPI_TABLE_PARSER ParserList[] = {
   {EFI_ACPI_6_2_MULTIPLE_APIC_DESCRIPTION_TABLE_SIGNATURE, ParseAcpiMadt},

   {EFI_ACPI_6_2_PCI_EXPRESS_MEMORY_MAPPED_CONFIGURATION_SPACE_BASE_ADDRESS_DESCRIPTION_TABLE_SIGNATURE,

    ParseAcpiMcfg},

+  {EFI_ACPI_6_2_PLATFORM_COMMUNICATIONS_CHANNEL_TABLE_SIGNATURE,

+   ParseAcpiPcct},

   {EFI_ACPI_6_2_PROCESSOR_PROPERTIES_TOPOLOGY_TABLE_STRUCTURE_SIGNATURE,

    ParseAcpiPptt},

   {RSDP_TABLE_INFO, ParseAcpiRsdp},

diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
index 91459f9ec6..efa9c8784a 100644
--- a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
+++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.inf
@@ -1,7 +1,7 @@
 ##  @file

 # Provides Shell 'acpiview' command functions

 #

-# Copyright (c) 2016 - 2020, ARM Limited. All rights reserved.<BR>

+# Copyright (c) 2016 - 2020, Arm Limited. All rights reserved.<BR>

 #

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

 #

@@ -37,6 +37,8 @@
   Parsers/Madt/MadtParser.c

   Parsers/Madt/MadtParser.h

   Parsers/Mcfg/McfgParser.c

+  Parsers/Pcct/PcctParser.c

+  Parsers/Pcct/PcctParser.h

   Parsers/Pptt/PpttParser.c

   Parsers/Pptt/PpttParser.h

   Parsers/Rsdp/RsdpParser.c