Re: [edk2-devel] [PATCH 1/2] Mde Pkg: Support for MPAM ACPI Table

["Rohit Mathew" <rohit.mathew@arm.com>]

Hi Swatisri,

Thanks for the patch. Please find my comments inline marked [Rohit] -

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Name
> via groups.io
> Sent: 16 August 2022 21:18
> To: devel@edk2.groups.io; Sami Mujawar <Sami.Mujawar@arm.com>;
> Alexei Fedorov <Alexei.Fedorov@arm.com>; michael.d.kinney@intel.com;
> gaoliming@byosoft.com.cn; zhiguang.liu@intel.com
> Cc: Swatisri Kantamsetti <swatisrik@nvidia.com>
> Subject: [edk2-devel] [PATCH 1/2] Mde Pkg: Support for MPAM ACPI Table
> 
> From: Swatisri Kantamsetti <swatisrik@nvidia.com>
> 
> Added MPAM table header, MSC and Resource Node info structures
> 
> Signed-off-by: Swatisri Kantamsetti <swatisrik@nvidia.com>
> ---
>  MdePkg/Include/IndustryStandard/Acpi64.h |  5 ++
>  MdePkg/Include/IndustryStandard/Mpam.h   | 69
> ++++++++++++++++++++++++
>  2 files changed, 74 insertions(+)
>  create mode 100644 MdePkg/Include/IndustryStandard/Mpam.h
> 
> diff --git a/MdePkg/Include/IndustryStandard/Acpi64.h
> b/MdePkg/Include/IndustryStandard/Acpi64.h
> index fe5ebfac2b..e54f631186 100644
> --- a/MdePkg/Include/IndustryStandard/Acpi64.h
> +++ b/MdePkg/Include/IndustryStandard/Acpi64.h
> @@ -2952,6 +2952,11 @@ typedef struct {
>  ///
>  #define
> EFI_ACPI_6_4_PROCESSOR_PROPERTIES_TOPOLOGY_TABLE_STRUCTURE_SI
> GNATURE  SIGNATURE_32('P', 'P', 'T', 'T')
> 
> +///
> +/// "MPAM" Memory System Resource Partitioning And Monitoring Table
> ///
> +#define
> +EFI_ACPI_6_4_MEMORY_SYSTEM_RESOURCE_PARTITIONING_MONITORI
> NG_TABLE_STRUC
> +TURE_SIGNATURE  SIGNATURE_32('M', 'P', 'A', 'M')
> +
>  ///
>  /// "PSDT" Persistent System Description Table  /// diff --git
> a/MdePkg/Include/IndustryStandard/Mpam.h
> b/MdePkg/Include/IndustryStandard/Mpam.h
> new file mode 100644
> index 0000000000..e0f75f0114
> --- /dev/null
> +++ b/MdePkg/Include/IndustryStandard/Mpam.h
> @@ -0,0 +1,69 @@
> +/** @file
> +  ACPI Memory System Resource Partitioning And Monitoring (MPAM)
> +  as specified in ARM spec DEN0065
> +
> +  Copyright (c) 2022, NVIDIA CORPORATION. All rights reserved.
> +  Copyright (c) 2022, ARM Limited. All rights reserved.
> +  SPDX-License-Identifier: BSD-2-Clause-Patent **/
> +
> +#ifndef _MPAM_H_
> +#define _MPAM_H_
> +
> +#pragma pack(1)
> +
> +///
> +/// Memory System Resource Partitioning and Monitoring Table (MPAM)
> ///
> +typedef struct {
> +  EFI_ACPI_DESCRIPTION_HEADER    Header;
> +  UINT32                         NumNodes;
> +  UINT32                         NodeOffset;
> +  UINT32                         Reserved;
> +}
> +EFI_ACPI_6_4_MEMORY_SYSTEM_RESOURCE_PARTITIONING_MONITORI
> NG_TABLE_HEADE
> +R;

[Rohit] Shouldn't the header be followed by MSC node body type as defined in MPAM ACPI 1.0, section 2, table 3 - The MPAM table and section 2.1, table 4 - MSC Node body?

> +
> +///
> +/// MPAM Revision (as defined in ACPI 6.4 spec.) /// #define
> +EFI_ACPI_6_4_MEMORY_SYSTEM_RESOURCE_PARTITIONING_MONITORI
> NG_TABLE_REVIS
> +ION  0x01
> +
> +///
> +/// Memory System Controller Node Structure ///
> +
> +typedef struct {
> +  UINT16    Length;
> +  UINT16    Reserved;
> +  UINT32    Identifier;
> +  UINT64    BaseAddress;
> +  UINT32    MmioSize;
> +  UINT32    OverflowInterrupt;
> +  UINT32    OverflowInterruptFlags;

[Rohit] Would it be better to have a type (possibly bitfield struct) instead of a plain UINT32 for Flags? (MPAM ACPI 1.0, section 2.1.1, table 5 - Interrupt flags)

> +  UINT32    Reserved1;
> +  UINT32    OverflowInterruptAff;
> +  UINT32    ErrorInterrupt;
> +  UINT32    ErrorInterruptFlags;

[Rohit ] Same comment as before above.

> +  UINT32    Reserved2;
> +  UINT32    ErrorInterruptAff;
> +  UINT32    MaxNRdyUsec;
> +  UINT64    LinkedDeviceHwId;
> +  UINT32    LinkedDeviceInstanceHwId;
> +  UINT32    NumResourceNodes;
> +} EFI_ACPI_6_4_MPAM_MSC_NODE;
> +
> +///
> +/// Resource Node Structure
> +///
> +
> +typedef struct {
> +  UINT32    Identifier;
> +  UINT8     RisIndex;
> +  UINT16    Reserved1;
> +  UINT8     LocatorType;
> +  UINT64    Locator;

[Rohit ] Shouldn't " Locator " field be 12 bytes in size, possibly a separate type? (MPAM ACPI 1.0, section 2.2, table 7 - Resource node and section 2.3.2 table 10 - locator descriptor)

> +  UINT32    NumFuncDep;
> +} EFI_ACPI_6_4_MPAM_RESOURCE_NODE;

[Rohit] Since "NumFuncDep" field is part of EFI_ACPI_6_4_MPAM_RESOURCE_NODE type and this could be non-zero, should we also need the type for functional dependency descriptors? (MPAM ACPI 1.0, section 2.2.1, table 8 - Functional dependency descriptor)

[Rohit] Also, could some of the commonly used macros be added to this header, please? (location types, MPAM interrupt mode, interrupt types, affinity type, etc)

> +
> +#pragma pack()
> +
> +#endif
> --
> 2.17.1
> 
> 
> 
> 
> 

Regards,
Rohit