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

["PierreGondois" <pierre.gondois@arm.com>]

Hello Jeff,
To be sure I understand correctly, the SsdtPcieGenerator currently allows
to generate something like this:

Scope(_SB) {
   Device(PCI0) {
     Device (D00_) { // Device 0
       Name(_ADR, 0x0000FFFF)
     }
     Method(_OSC,4) {
       [...] // Generic _OSC method
     }
   }
}

What you want to do is:
1. Use another _OSC method
2. Add more information in the D00_ object, i.e.:
   - a _DSD object
   - a _RST method
3. As _RST is added in 2., also add a _RST method to PCI0

Is it correct ? Or is there some other information you want to add ?

Regards,
Pierre

On 7/8/22 17:36, Jeff Brasen wrote:
> I think this would work. Instead of GeneratePciDeviceInfo the function we would want to break out would be GeneratePciSlots. I'll work on changing my patch series to this. Unless you have a better name will call this library SsdtPciSupportLib and place in under Library/Common
> 
> Going to also pass PciInfo into AddOscMethod in this new approach in case client needs to have different _OSC per controller (And to GeneratePciSlots as well).
> 
> Thanks,
> Jeff
> 
>> -----Original Message-----
>> From: Pierre Gondois <pierre.gondois@arm.com>
>> Sent: Monday, July 4, 2022 2:48 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,
>> I think it would ideally be better to have the code adding/replacing the
>> methods/objects you noted inside the edk2/edk2-platfoms repositories. The
>> methods/objects that you want to replace seem to only concern:
>> -the objects available in the 'Device (PCIx)' node -the _OSC method
>>
>> If a library with the following two methods (extracted from
>> SsdtPcieLibArm.inf) was created, would it be sufficient for all the
>> replacements you want to do ?
>> Like this we would have a generic implementation and specific ones.
>>
>> EFI_STATUS
>> EFIAPI
>> GeneratePciDeviceInfo (
>>     IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO  *PciInfo,
>>     IN            UINT32                        Uid,
>>     IN  OUT       AML_OBJECT_NODE_HANDLE        PciNode
>>     )
>>
>> EFI_STATUS
>> EFIAPI
>> AddOscMethod (
>>     IN  OUT   AML_OBJECT_NODE_HANDLE  PciNode
>>     )
>>
>> Regards,
>> Pierre
>>
>> On 7/1/22 17:52, Jeff Brasen wrote:
>>> 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