Re: [PATCH 4/4] DynamicTablesPkg: AcpiSsdtPcieLibArm: Add support for override protocol

["Jeff Brasen" <jbrasen@nvidia.com>]

Currently we do the following in this call.

Remove and replace the _OSC method on certain targets. I originally had this pass the template over but removed that when I added this more generic override support
Add a _RST method to the root port device sub node
Add a _DSD for device properties
Conditionally add an entry for the device attached to the PCIe bus if we need to add properties or _RST methods. This will likely eventually move to another driver (which is the purpose of patch 2/4 in this series)

I figured trying to get the generator to handle that would be more difficult as these would be hard to generalize.


Thanks,
Jeff

> -----Original Message-----
> From: Pierre Gondois <pierre.gondois@arm.com>
> Sent: Friday, July 1, 2022 6:40 AM
> To: Jeff Brasen <jbrasen@nvidia.com>; devel@edk2.groups.io
> Cc: Sami.Mujawar@arm.com; Alexei.Fedorov@arm.com
> Subject: Re: [PATCH 4/4] DynamicTablesPkg: AcpiSsdtPcieLibArm: Add
> support for override protocol
> 
> External email: Use caution opening links or attachments
> 
> 
> Hello Jeff,
> Is it possible to know what the UpdateTable() function would do ?
> Maybe it would be possible to integrate the alternative implementation
> without adding a new protocol.
> 
> Regards,
> Pierre
> 
> On 6/30/22 17:48, Jeff Brasen wrote:
> > Some platfoms may want to modify the ACPI table created.
> > Add support for protocol that can provide an alternative implementation.
> >
> > Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
> > ---
> >   DynamicTablesPkg/DynamicTablesPkg.dec         |  3 +
> >   .../Protocol/SsdtPcieOverrideProtocol.h       | 63 +++++++++++++++++++
> >   .../AcpiSsdtPcieLibArm/SsdtPcieGenerator.c    | 31 ++++++++-
> >   .../Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.inf |  4 ++
> >   4 files changed, 98 insertions(+), 3 deletions(-)
> >   create mode 100644
> > DynamicTablesPkg/Include/Protocol/SsdtPcieOverrideProtocol.h
> >
> > diff --git a/DynamicTablesPkg/DynamicTablesPkg.dec
> > b/DynamicTablesPkg/DynamicTablesPkg.dec
> > index a890a048be..bb66bdaf14 100644
> > --- a/DynamicTablesPkg/DynamicTablesPkg.dec
> > +++ b/DynamicTablesPkg/DynamicTablesPkg.dec
> > @@ -43,6 +43,9 @@
> >     # Dynamic Table Factory Protocol GUID
> >     gEdkiiDynamicTableFactoryProtocolGuid = { 0x91d1e327, 0xfe5a,
> > 0x49b8, { 0xab, 0x65, 0xe, 0xce, 0x2d, 0xdb, 0x45, 0xec } }
> >
> > +  # Protocol to override PCI SSDT table generation
> > + gEdkiiDynamicTableSsdtPcieOverrideProtocolGuid = { 0x962e8b44,
> > + 0x23b3, 0x41da, { 0x9f, 0x36, 0xca, 0xde, 0x68, 0x49, 0xfb, 0xf6 } }
> > +
> >   [PcdsFixedAtBuild]
> >
> >     # Maximum number of Custom ACPI Generators diff --git
> > a/DynamicTablesPkg/Include/Protocol/SsdtPcieOverrideProtocol.h
> > b/DynamicTablesPkg/Include/Protocol/SsdtPcieOverrideProtocol.h
> > new file mode 100644
> > index 0000000000..29568a0159
> > --- /dev/null
> > +++ b/DynamicTablesPkg/Include/Protocol/SsdtPcieOverrideProtocol.h
> > @@ -0,0 +1,63 @@
> > +/** @file
> > +
> > +  Copyright (c) 2022, NVIDIA CORPORATION. All rights reserved.
> > +
> > +  SPDX-License-Identifier: BSD-2-Clause-Patent
> > +
> > +**/
> > +
> > +#ifndef SSDT_PCIE_OVERRIDE_PROTOCOL_H_ #define
> > +SSDT_PCIE_OVERRIDE_PROTOCOL_H_
> > +
> > +#include <ArmNameSpaceObjects.h>
> > +#include <Library/AmlLib/AmlLib.h>
> > +
> > +/** This macro defines the SSDT PCI Override Protocol GUID.
> > +
> > +  GUID: {D85A4835-5A82-4894-AC02-706F43D5978E}
> > +*/
> > +#define EDKII_SSDT_PCI_OVERRIDE_PROTOCOL_GUID           \
> > +  { 0x962e8b44, 0x23b3, 0x41da,                         \
> > +    { 0x9f, 0x36, 0xca, 0xde, 0x68, 0x49, 0xfb, 0xf6 }  \
> > +  };
> > +
> > +/**
> > +  Forward declarations:
> > +*/
> > +typedef struct SsdtOverridePciProtocol
> > +EDKII_SSDT_PCI_OVERRIDE_PROTOCOL;
> > +
> > +/** The UpdateTable function allows the override protocol to update the
> > + *   PCIe SSDT table prior to being created.
> > +
> > +  @param [in]      This    Pointer to the SSDT PCI Override Protocol.
> > +  @param [in]      PciInfo The PCIe configuration info for this node.
> > +  @param [in]      Uid     UID that was selected for this PCIe node.
> > +  @param [in, out] PciNode Pointer to the PCI node of this ACPI table.
> > +
> > +  @retval EFI_SUCCESS           Success.
> > +  @retval EFI_INVALID_PARAMETER A parameter is invalid.
> > +  @retval EFI_DEVICE_ERROR      Failed to update the table.
> > +**/
> > +typedef
> > +EFI_STATUS
> > +(EFIAPI *EDKII_SSDT_PCI_OVERRIDE_PROTOCOL_UPDATE_TABLE)(
> > +  IN      CONST EDKII_SSDT_PCI_OVERRIDE_PROTOCOL  *CONST  This,
> > +  IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO              *PciInfo,
> > +  IN            UINT32                                    Uid,
> > +  IN  OUT       AML_ROOT_NODE_HANDLE                      *PciNode
> > +  );
> > +
> > +/** The EDKII_CONFIGURATION_MANAGER_PROTOCOL structure
> describes the
> > +    Configuration Manager Protocol interface.
> > +*/
> > +typedef struct SsdtOverridePciProtocol {
> > +  /** The interface used to update the ACPI table for PCI.
> > +  */
> > +  EDKII_SSDT_PCI_OVERRIDE_PROTOCOL_UPDATE_TABLE    UpdateTable;
> > +} EDKII_SSDT_PCI_OVERRIDE_PROTOCOL;
> > +
> > +/** The SSDT PCI Override Protocol GUID.
> > +*/
> > +extern EFI_GUID  gEdkiiDynamicTableSsdtPcieOverrideProtocolGuid;
> > +
> > +#endif // SSDT_PCIE_OVERRIDE_PROTOCOL_H_
> > diff --git
> >
> a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenera
> t
> > or.c
> >
> b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenera
> t
> > or.c
> > index c5b23d91d0..d5982c24ff 100644
> > ---
> >
> a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenera
> t
> > or.c
> > +++
> b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGen
> > +++ erator.c
> > @@ -20,6 +20,7 @@
> >   #include <Library/BaseMemoryLib.h>
> >   #include <Library/DebugLib.h>
> >   #include <Library/MemoryAllocationLib.h>
> > +#include <Library/UefiBootServicesTableLib.h>
> >   #include <Protocol/AcpiTable.h>
> >
> >   // Module specific include files.
> > @@ -30,6 +31,7 @@
> >   #include <Library/TableHelperLib.h>
> >   #include <Library/AmlLib/AmlLib.h>
> >   #include <Protocol/ConfigurationManagerProtocol.h>
> > +#include <Protocol/SsdtPcieOverrideProtocol.h>
> >
> >   #include "SsdtPcieGenerator.h"
> >
> > @@ -798,9 +800,10 @@ GeneratePciDevice (
> >   {
> >     EFI_STATUS  Status;
> >
> > -  CHAR8                   AslName[AML_NAME_SEG_SIZE + 1];
> > -  AML_OBJECT_NODE_HANDLE  ScopeNode;
> > -  AML_OBJECT_NODE_HANDLE  PciNode;
> > +  CHAR8                             AslName[AML_NAME_SEG_SIZE + 1];
> > +  AML_OBJECT_NODE_HANDLE            ScopeNode;
> > +  AML_OBJECT_NODE_HANDLE            PciNode;
> > +  EDKII_SSDT_PCI_OVERRIDE_PROTOCOL  *OverrideProtocol;
> >
> >     ASSERT (Generator != NULL);
> >     ASSERT (CfgMgrProtocol != NULL);
> > @@ -860,6 +863,28 @@ GeneratePciDevice (
> >
> >     // Add the template _OSC method.
> >     Status = AddOscMethod (PciNode);
> > +  if (EFI_ERROR (Status)) {
> > +    ASSERT (0);
> > +    return Status;
> > +  }
> > +
> > +  Status = gBS->LocateProtocol (
> > +                  &gEdkiiDynamicTableSsdtPcieOverrideProtocolGuid,
> > +                  NULL,
> > +                  (VOID **)&OverrideProtocol
> > +                  );
> > +  if (!EFI_ERROR (Status)) {
> > +    Status = OverrideProtocol->UpdateTable (
> > +                                 OverrideProtocol,
> > +                                 PciInfo,
> > +                                 Uid,
> > +                                 PciNode
> > +                                 );
> > +  } else {
> > +    // Not an error if override protocol is not found
> > +    Status = EFI_SUCCESS;
> > +  }
> > +
> >     ASSERT_EFI_ERROR (Status);
> >     return Status;
> >   }
> > diff --git
> >
> a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.
> > inf
> >
> b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.
> > inf
> > index 431e32a777..8e916f15e9 100644
> > ---
> >
> a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.
> > inf
> > +++
> b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLib
> > +++ Arm.inf
> > @@ -30,6 +30,10 @@
> >     AcpiHelperLib
> >     AmlLib
> >     BaseLib
> > +  UefiBootServicesTableLib
> >
> >   [Pcd]
> >     gEdkiiDynamicTablesPkgTokenSpaceGuid.PcdPciUseSegmentAsUid
> > +
> > +[Protocols]
> > +  gEdkiiDynamicTableSsdtPcieOverrideProtocolGuid