system76-edk2/EmbeddedPkg/Library/CoherentDmaLib/CoherentDmaLib.c

/** @file
  Generic ARM implementation of DmaLib.h

  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>

  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <Uefi.h>
#include <Library/DebugLib.h>
#include <Library/DmaLib.h>
#include <Library/MemoryAllocationLib.h>


STATIC
PHYSICAL_ADDRESS
HostToDeviceAddress (
  IN  VOID      *Address
  )
{
  return (PHYSICAL_ADDRESS)(UINTN)Address + PcdGet64 (PcdDmaDeviceOffset);
}

/**
  Provides the DMA controller-specific addresses needed to access system memory.

  Operation is relative to the DMA bus master.

  @param  Operation             Indicates if the bus master is going to read or write to system memory.
  @param  HostAddress           The system memory address to map to the DMA controller.
  @param  NumberOfBytes         On input the number of bytes to map. On output the number of bytes
                                that were mapped.
  @param  DeviceAddress         The resulting map address for the bus master controller to use to
                                access the hosts HostAddress.
  @param  Mapping               A resulting value to pass to Unmap().

  @retval EFI_SUCCESS           The range was mapped for the returned NumberOfBytes.
  @retval EFI_UNSUPPORTED       The HostAddress cannot be mapped as a common buffer.
  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  @retval EFI_OUT_OF_RESOURCES  The request could not be completed due to a lack of resources.
  @retval EFI_DEVICE_ERROR      The system hardware could not map the requested address.

**/
EFI_STATUS
EFIAPI
DmaMap (
  IN     DMA_MAP_OPERATION              Operation,
  IN     VOID                           *HostAddress,
  IN OUT UINTN                          *NumberOfBytes,
  OUT    PHYSICAL_ADDRESS               *DeviceAddress,
  OUT    VOID                           **Mapping
  )
{
  if (HostAddress == NULL ||
      NumberOfBytes == NULL ||
      DeviceAddress == NULL ||
      Mapping == NULL ) {
    return EFI_INVALID_PARAMETER;
  }
  *DeviceAddress = HostToDeviceAddress (HostAddress);
  *Mapping = NULL;
  return EFI_SUCCESS;
}


/**
  Completes the DmaMapBusMasterRead(), DmaMapBusMasterWrite(), or DmaMapBusMasterCommonBuffer()
  operation and releases any corresponding resources.

  @param  Mapping               The mapping value returned from DmaMap*().

  @retval EFI_SUCCESS           The range was unmapped.
  @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.

**/
EFI_STATUS
EFIAPI
DmaUnmap (
  IN  VOID                         *Mapping
  )
{
  return EFI_SUCCESS;
}

/**
  Allocates pages that are suitable for an DmaMap() of type MapOperationBusMasterCommonBuffer.
  mapping.

  @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
                                EfiRuntimeServicesData.
  @param  Pages                 The number of pages to allocate.
  @param  HostAddress           A pointer to store the base system memory address of the
                                allocated range.

                                @retval EFI_SUCCESS           The requested memory pages were allocated.
  @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
                                MEMORY_WRITE_COMBINE and MEMORY_CACHED.
  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.

**/
EFI_STATUS
EFIAPI
DmaAllocateBuffer (
  IN  EFI_MEMORY_TYPE              MemoryType,
  IN  UINTN                        Pages,
  OUT VOID                         **HostAddress
  )
{
  return DmaAllocateAlignedBuffer (MemoryType, Pages, 0, HostAddress);
}


/**
  Allocates pages that are suitable for an DmaMap() of type
  MapOperationBusMasterCommonBuffer mapping, at the requested alignment.

  @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
                                EfiRuntimeServicesData.
  @param  Pages                 The number of pages to allocate.
  @param  Alignment             Alignment in bytes of the base of the returned
                                buffer (must be a power of 2)
  @param  HostAddress           A pointer to store the base system memory address of the
                                allocated range.

  @retval EFI_SUCCESS           The requested memory pages were allocated.
  @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
                                MEMORY_WRITE_COMBINE and MEMORY_CACHED.
  @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.

**/
EFI_STATUS
EFIAPI
DmaAllocateAlignedBuffer (
  IN  EFI_MEMORY_TYPE              MemoryType,
  IN  UINTN                        Pages,
  IN  UINTN                        Alignment,
  OUT VOID                         **HostAddress
  )
{
  if (Alignment == 0) {
    Alignment = EFI_PAGE_SIZE;
  }

  if (HostAddress == NULL ||
      (Alignment & (Alignment - 1)) != 0) {
    return EFI_INVALID_PARAMETER;
  }

  //
  // The only valid memory types are EfiBootServicesData and EfiRuntimeServicesData
  //
  if (MemoryType == EfiBootServicesData) {
    *HostAddress = AllocateAlignedPages (Pages, Alignment);
  } else if (MemoryType == EfiRuntimeServicesData) {
    *HostAddress = AllocateAlignedRuntimePages (Pages, Alignment);
  } else {
    return EFI_INVALID_PARAMETER;
  }

  if (*HostAddress == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }
  return EFI_SUCCESS;
}


/**
  Frees memory that was allocated with DmaAllocateBuffer().

  @param  Pages                 The number of pages to free.
  @param  HostAddress           The base system memory address of the allocated range.

  @retval EFI_SUCCESS           The requested memory pages were freed.
  @retval EFI_INVALID_PARAMETER The memory range specified by HostAddress and Pages
                                was not allocated with DmaAllocateBuffer().

**/
EFI_STATUS
EFIAPI
DmaFreeBuffer (
  IN  UINTN                        Pages,
  IN  VOID                         *HostAddress
  )
{
  if (HostAddress == NULL) {
     return EFI_INVALID_PARAMETER;
  }

  FreePages (HostAddress, Pages);
  return EFI_SUCCESS;
}