Re: [PATCH 10/10] ArmPkg/MmCommunicationDxe: signal architected PI events into MM context

["Yao, Jiewen" <jiewen.yao@intel.com>]

Hi
In original SMM infrastructure, there are lots of interaction that SMM has to know the DXE status.

In StandaloneMm, I don't expect we have many interaction. Is there any specific example?

I am totally OK to add those. And I just want to know more usage.

Reviewed-by: Jiewen.yao@intel.com


Thank you
Yao Jiewen

> -----Original Message-----
> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> Sent: Tuesday, March 5, 2019 5:33 AM
> To: edk2-devel@lists.01.org
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>; Achin Gupta
> <achin.gupta@arm.com>; Supreeth Venkatesh
> <supreeth.venkatesh@arm.com>; Yao, Jiewen <jiewen.yao@intel.com>;
> Leif Lindholm <leif.lindholm@linaro.org>; Jagadeesh Ujja
> <jagadeesh.ujja@arm.com>
> Subject: [PATCH 10/10] ArmPkg/MmCommunicationDxe: signal architected
> PI events into MM context
> 
> PI defines a few architected events that have significance in the MM
> context as well as in the non-secure DXE context. So register notify
> handlers for these events, and relay them into the standalone MM world.
> 
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf |  5 +++
>  ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c   | 47
> +++++++++++++++++++-
>  2 files changed, 50 insertions(+), 2 deletions(-)
> 
> diff --git a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
> b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
> index 88beafa39c05..8bf269270f9d 100644
> --- a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
> +++ b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
> @@ -48,6 +48,11 @@ [LibraryClasses]
>  [Protocols]
>    gEfiMmCommunicationProtocolGuid              ## PRODUCES
> 
> +[Guids]
> +  gEfiEndOfDxeEventGroupGuid
> +  gEfiEventExitBootServicesGuid
> +  gEfiEventReadyToBootGuid
> +
>  [Pcd.common]
>    gArmTokenSpaceGuid.PcdMmBufferBase
>    gArmTokenSpaceGuid.PcdMmBufferSize
> diff --git a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
> b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
> index feb9fa9f4ead..3203cf801a19 100644
> --- a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
> +++ b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
> @@ -265,6 +265,43 @@ GetMmCompatibility ()
>    return Status;
>  }
> 
> +STATIC EFI_GUID* CONST mGuidedEventGuid[] = {
> +  &gEfiEndOfDxeEventGroupGuid,
> +  &gEfiEventExitBootServicesGuid,
> +  &gEfiEventReadyToBootGuid,
> +};
> +
> +STATIC EFI_EVENT mGuidedEvent[ARRAY_SIZE (mGuidedEventGuid)];
> +
> +/**
> +  Event notification that is fired when GUIDed Event Group is signaled.
> +
> +  @param  Event                 The Event that is being processed,
> not used.
> +  @param  Context               Event Context, not used.
> +
> +**/
> +STATIC
> +VOID
> +EFIAPI
> +MmGuidedEventNotify (
> +  IN EFI_EVENT  Event,
> +  IN VOID       *Context
> +  )
> +{
> +  EFI_MM_COMMUNICATE_HEADER   Header;
> +  UINTN                       Size;
> +
> +  //
> +  // Use Guid to initialize EFI_SMM_COMMUNICATE_HEADER structure
> +  //
> +  CopyGuid (&Header.HeaderGuid, Context);
> +  Header.MessageLength = 1;
> +  Header.Data[0] = 0;
> +
> +  Size = sizeof (Header);
> +  MmCommunicationCommunicate (&mMmCommunication, &Header,
> &Size);
> +}
> +
>  /**
>    The Entry Point for MM Communication
> 
> @@ -287,6 +324,7 @@ MmCommunicationInitialize (
>    )
>  {
>    EFI_STATUS                 Status;
> +  UINTN                      Index;
> 
>    // Check if we can make the MM call
>    Status = GetMmCompatibility ();
> @@ -351,8 +389,13 @@ MmCommunicationInitialize (
>                    NULL,
>                    &mSetVirtualAddressMapEvent
>                    );
> -  if (Status == EFI_SUCCESS) {
> -    return Status;
> +  ASSERT_EFI_ERROR (Status);
> +
> +  for (Index = 0; Index < ARRAY_SIZE (mGuidedEventGuid); Index++) {
> +    Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
> +                    MmGuidedEventNotify, mGuidedEventGuid[Index],
> +                    mGuidedEventGuid[Index],
> &mGuidedEvent[Index]);
> +    ASSERT_EFI_ERROR (Status);
>    }
> 
>    gBS->UninstallProtocolInterface (
> --
> 2.20.1