/** @file
  Produces the SMM CPU I/O Protocol.

Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials                          
are licensed and made available under the terms and conditions of the BSD License         
which accompanies this distribution.  The full text of the license may be found at        
http://opensource.org/licenses/bsd-license.php                                            
                                                                                          
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             

**/

#include "CpuIo2Smm.h"

//
// Handle for the SMM CPU I/O Protocol
//
EFI_HANDLE  mHandle = NULL;

//
// SMM CPU I/O Protocol instance
//
EFI_SMM_CPU_IO2_PROTOCOL mSmmCpuIo2 = {
  {
    CpuMemoryServiceRead,
    CpuMemoryServiceWrite
  },
  {
    CpuIoServiceRead,
    CpuIoServiceWrite
  }
};

//
// Lookup table for increment values based on transfer widths
//
UINT8 mStride[] = {
  1, // SMM_IO_UINT8
  2, // SMM_IO_UINT16
  4, // SMM_IO_UINT32
  8  // SMM_IO_UINT64
};

/**
  Check parameters to a SMM CPU I/O Protocol service request.

  @param[in]  MmioOperation  TRUE for an MMIO operation, FALSE for I/O Port operation.
  @param[in]  Width          Signifies the width of the I/O operations.
  @param[in]  Address        The base address of the I/O operations.  The caller is 
                             responsible for aligning the Address if required. 
  @param[in]  Count          The number of I/O operations to perform.
  @param[in]  Buffer         For read operations, the destination buffer to store 
                             the results.  For write operations, the source buffer 
                             from which to write data.

  @retval EFI_SUCCESS            The data was read from or written to the device.
  @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
                                 
**/
EFI_STATUS
CpuIoCheckParameter (
  IN BOOLEAN           MmioOperation,
  IN EFI_SMM_IO_WIDTH  Width,
  IN UINT64            Address,
  IN UINTN             Count,
  IN VOID              *Buffer
  )
{
  UINT64  MaxCount;
  UINT64  Limit;

  //
  // Check to see if Buffer is NULL
  //
  if (Buffer == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Check to see if Width is in the valid range
  //
  if (Width < 0 || Width > SMM_IO_UINT64) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // Check to see if Width is in the valid range for I/O Port operations
  //
  if (!MmioOperation && (Width == SMM_IO_UINT64)) {
    return EFI_INVALID_PARAMETER;
  }
  
  //
  // Check to see if any address associated with this transfer exceeds the maximum 
  // allowed address.  The maximum address implied by the parameters passed in is
  // Address + Size * Count.  If the following condition is met, then the transfer
  // is not supported.
  //
  //    Address + Size * Count > (MmioOperation ? MAX_ADDRESS : MAX_IO_PORT_ADDRESS) + 1
  //
  // Since MAX_ADDRESS can be the maximum integer value supported by the CPU and Count 
  // can also be the maximum integer value supported by the CPU, this range
  // check must be adjusted to avoid all overflow conditions.
  //   
  // The following form of the range check is equivalent but assumes that 
  // MAX_ADDRESS and MAX_IO_PORT_ADDRESS are of the form (2^n - 1).
  //
  Limit = (MmioOperation ? MAX_ADDRESS : MAX_IO_PORT_ADDRESS);
  if (Count == 0) {
    if (Address > Limit) {
      return EFI_UNSUPPORTED;
    }
  } else {  
    MaxCount = RShiftU64 (Limit, Width);
    if (MaxCount < (Count - 1)) {
      return EFI_UNSUPPORTED;
    }
    if (Address > LShiftU64 (MaxCount - Count + 1, Width)) {
      return EFI_UNSUPPORTED;
    }
  }
  
  //
  // Check to see if Address is aligned
  //
  if ((Address & (UINT64)(mStride[Width] - 1)) != 0) {
    return EFI_UNSUPPORTED;
  }

  return EFI_SUCCESS;
}

/**
  Reads memory-mapped registers.

  The I/O operations are carried out exactly as requested.  The caller is 
  responsible for any alignment and I/O width issues that the bus, device, 
  platform, or type of I/O might require.

  @param[in]  This     The EFI_SMM_CPU_IO2_PROTOCOL instance.
  @param[in]  Width    Signifies the width of the I/O operations.
  @param[in]  Address  The base address of the I/O operations.  The caller is 
                       responsible for aligning the Address if required. 
  @param[in]  Count    The number of I/O operations to perform.
  @param[out] Buffer   For read operations, the destination buffer to store 
                       the results.  For write operations, the source buffer 
                       from which to write data.

  @retval EFI_SUCCESS            The data was read from or written to the device.
  @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a 
                                 lack of resources

**/
EFI_STATUS
EFIAPI
CpuMemoryServiceRead (
  IN  CONST EFI_SMM_CPU_IO2_PROTOCOL  *This,
  IN  EFI_SMM_IO_WIDTH                Width,
  IN  UINT64                          Address,
  IN  UINTN                           Count,
  OUT VOID                            *Buffer
  )
{
  EFI_STATUS  Status;
  UINT8       Stride;
  UINT8       *Uint8Buffer;

  Status = CpuIoCheckParameter (TRUE, Width, Address, Count, Buffer);
  if (EFI_ERROR(Status)) {
    return Status;
  }

  //
  // Select loop based on the width of the transfer
  //
  Stride = mStride[Width];
  for (Uint8Buffer = Buffer; Count > 0; Address += Stride, Uint8Buffer += Stride, Count--) {
    if (Width == SMM_IO_UINT8) {
      *Uint8Buffer = MmioRead8 ((UINTN)Address);
    } else if (Width == SMM_IO_UINT16) {
      *((UINT16 *)Uint8Buffer) = MmioRead16 ((UINTN)Address);
    } else if (Width == SMM_IO_UINT32) {
      *((UINT32 *)Uint8Buffer) = MmioRead32 ((UINTN)Address);
    } else if (Width == SMM_IO_UINT64) {
      *((UINT64 *)Uint8Buffer) = MmioRead64 ((UINTN)Address);
    }
  }
  return EFI_SUCCESS;
}

/**
  Writes memory-mapped registers.

  The I/O operations are carried out exactly as requested.  The caller is 
  responsible for any alignment and I/O width issues that the bus, device, 
  platform, or type of I/O might require.

  @param[in]  This     The EFI_SMM_CPU_IO2_PROTOCOL instance.
  @param[in]  Width    Signifies the width of the I/O operations.
  @param[in]  Address  The base address of the I/O operations.  The caller is 
                       responsible for aligning the Address if required. 
  @param[in]  Count    The number of I/O operations to perform.
  @param[in]  Buffer   For read operations, the destination buffer to store 
                       the results.  For write operations, the source buffer 
                       from which to write data.

  @retval EFI_SUCCESS            The data was read from or written to the device.
  @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a 
                                 lack of resources

**/
EFI_STATUS
EFIAPI
CpuMemoryServiceWrite (
  IN CONST EFI_SMM_CPU_IO2_PROTOCOL  *This,
  IN EFI_SMM_IO_WIDTH                Width,
  IN UINT64                          Address,
  IN UINTN                           Count,
  IN VOID                            *Buffer
  )
{
  EFI_STATUS  Status;
  UINT8       Stride;
  UINT8       *Uint8Buffer;

  Status = CpuIoCheckParameter (TRUE, Width, Address, Count, Buffer);
  if (EFI_ERROR(Status)) {
    return Status;
  }

  //
  // Select loop based on the width of the transfer
  //
  Stride = mStride[Width];
  for (Uint8Buffer = Buffer; Count > 0; Address += Stride, Uint8Buffer += Stride, Count--) {
    if (Width == SMM_IO_UINT8) {
      MmioWrite8 ((UINTN)Address, *Uint8Buffer);
    } else if (Width == SMM_IO_UINT16) {
      MmioWrite16 ((UINTN)Address, *((UINT16 *)Uint8Buffer));
    } else if (Width == SMM_IO_UINT32) {
      MmioWrite32 ((UINTN)Address, *((UINT32 *)Uint8Buffer));
    } else if (Width == SMM_IO_UINT64) {
      MmioWrite64 ((UINTN)Address, *((UINT64 *)Uint8Buffer));
    }
  }
  return EFI_SUCCESS;
}

/**
  Reads I/O registers.

  The I/O operations are carried out exactly as requested.  The caller is 
  responsible for any alignment and I/O width issues that the bus, device, 
  platform, or type of I/O might require.

  @param[in]  This     The EFI_SMM_CPU_IO2_PROTOCOL instance.
  @param[in]  Width    Signifies the width of the I/O operations.
  @param[in]  Address  The base address of the I/O operations.  The caller is 
                       responsible for aligning the Address if required. 
  @param[in]  Count    The number of I/O operations to perform.
  @param[out] Buffer   For read operations, the destination buffer to store 
                       the results.  For write operations, the source buffer 
                       from which to write data.

  @retval EFI_SUCCESS            The data was read from or written to the device.
  @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a 
                                 lack of resources

**/
EFI_STATUS
EFIAPI
CpuIoServiceRead (
  IN  CONST EFI_SMM_CPU_IO2_PROTOCOL  *This,
  IN  EFI_SMM_IO_WIDTH                Width,
  IN  UINT64                          Address,
  IN  UINTN                           Count,
  OUT VOID                            *Buffer
  )
{
  EFI_STATUS  Status;
  UINT8       Stride;
  UINT8       *Uint8Buffer;

  Status = CpuIoCheckParameter (FALSE, Width, Address, Count, Buffer);
  if (EFI_ERROR(Status)) {
    return Status;
  }

  //
  // Select loop based on the width of the transfer
  //
  Stride = mStride[Width];
  for (Uint8Buffer = Buffer; Count > 0; Address += Stride, Uint8Buffer += Stride, Count--) {
    if (Width == SMM_IO_UINT8) {
      *Uint8Buffer = IoRead8 ((UINTN)Address);
    } else if (Width == SMM_IO_UINT16) {
      *((UINT16 *)Uint8Buffer) = IoRead16 ((UINTN)Address);
    } else if (Width == SMM_IO_UINT32) {
      *((UINT32 *)Uint8Buffer) = IoRead32 ((UINTN)Address);
    }
  }

  return EFI_SUCCESS;
}

/**
  Write I/O registers.

  The I/O operations are carried out exactly as requested.  The caller is 
  responsible for any alignment and I/O width issues that the bus, device, 
  platform, or type of I/O might require.

  @param[in]  This     The EFI_SMM_CPU_IO2_PROTOCOL instance.
  @param[in]  Width    Signifies the width of the I/O operations.
  @param[in]  Address  The base address of the I/O operations.  The caller is 
                       responsible for aligning the Address if required. 
  @param[in]  Count    The number of I/O operations to perform.
  @param[in]  Buffer   For read operations, the destination buffer to store 
                       the results.  For write operations, the source buffer 
                       from which to write data.

  @retval EFI_SUCCESS            The data was read from or written to the device.
  @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a 
                                 lack of resources

**/
EFI_STATUS
EFIAPI
CpuIoServiceWrite (
  IN CONST EFI_SMM_CPU_IO2_PROTOCOL  *This,
  IN EFI_SMM_IO_WIDTH                Width,
  IN UINT64                          Address,
  IN UINTN                           Count,
  IN VOID                            *Buffer
  )
{
  EFI_STATUS  Status;
  UINT8       Stride;
  UINT8       *Uint8Buffer;

  //
  // Make sure the parameters are valid
  //
  Status = CpuIoCheckParameter (FALSE, Width, Address, Count, Buffer);
  if (EFI_ERROR(Status)) {
    return Status;
  }

  //
  // Select loop based on the width of the transfer
  //
  Stride = mStride[Width];
  for (Uint8Buffer = (UINT8 *)Buffer; Count > 0; Address += Stride, Uint8Buffer += Stride, Count--) {
    if (Width == SMM_IO_UINT8) {
      IoWrite8 ((UINTN)Address, *Uint8Buffer);
    } else if (Width == SMM_IO_UINT16) {
      IoWrite16 ((UINTN)Address, *((UINT16 *)Uint8Buffer));
    } else if (Width == SMM_IO_UINT32) {
      IoWrite32 ((UINTN)Address, *((UINT32 *)Uint8Buffer));
    }
  }
  
  return EFI_SUCCESS;
}

/**
  The module Entry Point SmmCpuIoProtocol driver

  @param[in] ImageHandle  The firmware allocated handle for the EFI image.
  @param[in] SystemTable  A pointer to the EFI System Table.

  @retval EFI_SUCCESS  The entry point is executed successfully.
  @retval Other        Some error occurs when executing this entry point.

**/
EFI_STATUS
EFIAPI
SmmCpuIo2Initialize (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  EFI_STATUS  Status;

  //
  // Copy the SMM CPU I/O Protocol instance into the System Management System Table
  //
  CopyMem (&gSmst->SmmIo, &mSmmCpuIo2, sizeof (mSmmCpuIo2));

  //
  // Install the SMM CPU I/O Protocol into the SMM protocol database
  //
  Status = gSmst->SmmInstallProtocolInterface (
                    &mHandle,
                    &gEfiSmmCpuIo2ProtocolGuid,
                    EFI_NATIVE_INTERFACE,
                    &mSmmCpuIo2
                    );
  ASSERT_EFI_ERROR(Status);
  
  return Status;
}