Re: [edk2-devel] [PATCH v2-resend 1/2] ShellPkg/AcpiView: PCCT Parser

["Gao, Zhichao" <zhichao.gao@intel.com>]

Apologize for the mistake.
I would add the RB to the patches on your branch https://github.com/samimujawar/edk2/commits/840_pcct_parser_v2.

Thanks,
Zhichao

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Sami
> Mujawar
> Sent: Thursday, December 10, 2020 5:06 PM
> To: Gao, Zhichao <zhichao.gao@intel.com>; devel@edk2.groups.io
> Cc: Ni, Ray <ray.ni@intel.com>; Matteo Carlini <Matteo.Carlini@arm.com>; Ben
> Adderson <Ben.Adderson@arm.com>; nd <nd@arm.com>
> Subject: Re: [edk2-devel] [PATCH v2-resend 1/2] ShellPkg/AcpiView: PCCT Parser
> 
> Hi Zhichao,
> 
> Thank you for reviewing the patches.
> 
> There was a mistake in the patch subject line when I reordered the patches.
> I had fixed these and resent the patch series. There is no code change the
> patches are just reordered and the subject lines fixed.
> 
> The links for the correct patches are:
> https://edk2.groups.io/g/devel/message/66989?p=,,,20,0,0,0::Created,,ShellPkg
> %2FAcpiView%3A,20,2,0,78027441
> https://edk2.groups.io/g/devel/message/66991?p=,,,20,0,0,0::Created,,ShellPkg
> %2FAcpiView%3A,20,2,0,78027603
> https://edk2.groups.io/g/devel/message/66990?p=,,,20,0,0,0::Created,,ShellPkg
> %2FAcpiView%3A,20,2,0,78027598
> 
> Apologies for the trouble.
> 
> Regards,
> 
> Sami Mujawar
> 
> -----Original Message-----
> From: Gao, Zhichao <zhichao.gao@intel.com>
> Sent: 10 December 2020 08:49 AM
> To: Sami Mujawar <Sami.Mujawar@arm.com>; devel@edk2.groups.io
> Cc: Ni, Ray <ray.ni@intel.com>; Matteo Carlini <Matteo.Carlini@arm.com>; Ben
> Adderson <Ben.Adderson@arm.com>; nd <nd@arm.com>
> Subject: RE: [PATCH v2-resend 1/2] ShellPkg/AcpiView: PCCT Parser
> 
> Reviewed-by: Zhichao Gao <zhichao.gao@intel.com>
> 
> Thanks,
> Zhichao
> 
> > -----Original Message-----
> > From: Sami Mujawar <sami.mujawar@arm.com>
> > Sent: Wednesday, November 4, 2020 8:18 PM
> > To: devel@edk2.groups.io
> > Cc: Sami Mujawar <sami.mujawar@arm.com>; Ni, Ray <ray.ni@intel.com>;
> > Gao, Zhichao <zhichao.gao@intel.com>; Matteo.Carlini@arm.com;
> > Ben.Adderson@arm.com; nd@arm.com
> > Subject: [PATCH v2-resend 1/2] ShellPkg/AcpiView: PCCT Parser
> >
> > From: Marc Moisson-Franckhauser <marc.moisson-franckhauser@arm.com>
> >
> > 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>
> > ---
> >
> > Notes:
> >     v2:
> >      - Addressed review comments by adding validation functions     [SAMI]
> >        for Doorbell, Interrupt Ack and Error Status GAS fields.
> >        Also added validation to check if the global platform
> >        interrupt flag is set for type 4 structure.
> >
> >  ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h                    |  24 +-
> >  ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiTableParser.h               |   4
> > +-
> >  ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.c
> |
> > 615 ++++++++++++++++++++
> >  ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctParser.h
> |
> > 33 ++
> >
> > ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandL
> > ib.c
> > |   4 +-
> >
> >
> ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCommandLib.i
> > nf |   4 +-
> >  6 files changed, 679 insertions(+), 5 deletions(-)
> >
> > diff --git a/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
> > b/ShellPkg/Library/UefiShellAcpiViewCommandLib/AcpiParser.h
> > index
> >
> f81ccac7e118378aa185db4b625e5bcd75f78347..051fdf807abb1067a264c136364
> > bb6d145b38dab 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
> >
> 4f92596b90a6ee422d8d0959881015ffd3de4da0..0ebf79fb653ae3a8190273aee4
> > 52723c6213eb58 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
> >
> 0000000000000000000000000000000000000000..ca553d5953f05651d8df4c95d
> > 1e39a73eded5129
> > --- /dev/null
> > +++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctPa
> > +++ rs
> > +++ er.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
> >
> 0000000000000000000000000000000000000000..278dc83c5de8860cbb2b1e2b2
> > e277aa7c6c58698
> > --- /dev/null
> > +++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/Parsers/Pcct/PcctPa
> > +++ rs
> > +++ er.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/UefiShellAcpiViewComman
> > dLi
> > b.c
> > b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewComman
> > dLi
> > b.c
> > index
> >
> d2f26ff89f12e596702281c38ab0de3729aa68e4..feb80661cddc420670edb2d8c7a
> > 570b0a89272d8 100644
> > ---
> > a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewComman
> > dLi
> > b.c
> > +++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCo
> > +++ mm
> > +++ andLib.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_BA
> > SE_ADDRESS_DESCRIPTION_TABLE_SIGNATURE,
> >     ParseAcpiMcfg},
> > +
> >
> {EFI_ACPI_6_2_PLATFORM_COMMUNICATIONS_CHANNEL_TABLE_SIGNATURE,
> > +   ParseAcpiPcct},
> >
> >
> {EFI_ACPI_6_2_PROCESSOR_PROPERTIES_TOPOLOGY_TABLE_STRUCTURE_SIGN
> > ATURE,
> >     ParseAcpiPptt},
> >    {RSDP_TABLE_INFO, ParseAcpiRsdp},
> > diff --git
> > a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewComman
> > dLi
> > b.inf
> > b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewComman
> > dLi
> > b.inf
> > index
> >
> 91459f9ec632635ee453c5ef46f67445cd9eee0c..efa9c8784a6670e5a4f500e0ae5
> > 59a4938852f95 100644
> > ---
> > a/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewComman
> > dLi
> > b.inf
> > +++ b/ShellPkg/Library/UefiShellAcpiViewCommandLib/UefiShellAcpiViewCo
> > +++ mm
> > +++ andLib.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 @@
> > [Sources.common]
> >    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
> > --
> > 'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'
> 
> 
> 
> 
>