ArmPkg/Include/Protocol/PiMmCpuDriverEp.h

/** @file
  This file describes the PiMm Cpu Driver Entry Point Protocol.
  the protocol is for defining handler for mm communication request event
  according to cpu driver.

  Copyright (c) 2024, Arm Limited. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#ifndef PI_MM_CPU_DRIVER_EP_H_
#define PI_MM_CPU_DRIVER_EP_H_

#include <PiMm.h>

#define EDKII_PI_MM_CPU_DRIVER_EP_GUID  { \
  0x6ecbd5a1, 0xc0f8, 0x4702, { 0x83, 0x01, 0x4f, 0xc2, 0xc5, 0x47, 0x0a, 0x51 } \
  }

/**
  The PI Standalone MM entry point for handling mm communication request
  Here is an example of how the EDKII_PI_MM_CPU_DRIVER_EP_PROTOCOL
  is utilized in ARM:
    1. StandaloneMmCoreEntryPoint loads StandaloneMmCore.
    2. StandaloneMmCore dispatches all MM drivers,
       including the StandaloneMmCpu driver.
    3. The StandaloneMmCpu driver declares its MMI CPU entry point through
       the PI_MM_CPU_DRIVER_EP_PROTOCOL.
    4. After all drivers have been dispatched,
       StandaloneMmCoreEntryPoint retrieves the MMI CPU entry point
       by locating the protocol.
    5. The DelegatedEventLoop then calls the MM CPU entry point.

  See StandaloneMmPkg/StandaloneMmCoreEntryPoint/Arm/StandaloneMmCoreEntryPoint.c

  @param  [in] EventId            The event Id based on firmware.
  @param  [in] CommBufferAddr     Address of the communication buffer.

  @retval   EFI_SUCCESS             Success.
  @retval   EFI_INVALID_PARAMETER   A parameter was invalid.
  @retval   EFI_ACCESS_DENIED       Access not permitted.
  @retval   EFI_OUT_OF_RESOURCES    Out of resources.
  @retval   EFI_UNSUPPORTED         Operation not supported.
**/
typedef
EFI_STATUS
(EFIAPI *EDKII_PI_MM_CPU_DRIVER_ENTRYPOINT)(
  IN UINTN  EventId,
  IN UINTN  CommBufferAddr
  );

typedef struct _EDKII_PI_MM_CPU_DRIVER_EP_PROTOCOL EDKII_PI_MM_CPU_DRIVER_EP_PROTOCOL;

struct _EDKII_PI_MM_CPU_DRIVER_EP_PROTOCOL {
  EDKII_PI_MM_CPU_DRIVER_ENTRYPOINT    PiMmCpuDriverEntryPoint;
};

extern EFI_GUID  gEdkiiPiMmCpuDriverEpProtocolGuid;

#endif