EmbeddedPkg/Include/Library/DmaLib.h

   1 /** @file
   2   DMA abstraction library APIs. Based on UEFI PCI IO protocol DMA abstractions.
   3   At some point these functions will probably end up in a non PCI protocol
   4   for embedded systems.
   5
   6   DMA Bus Master Read Operation:
   7     Call DmaMap() for MapOperationBusMasterRead.
   8     Program the DMA Bus Master with the DeviceAddress returned by DmaMap().
   9     Start the DMA Bus Master.
  10     Wait for DMA Bus Master to complete the read operation.
  11     Call DmaUnmap().
  12
  13   DMA Bus Master Write Operation:
  14     Call DmaMap() for MapOperationBusMasterWrite.
  15     Program the DMA Bus Master with the DeviceAddress returned by DmaMap().
  16     Start the DMA Bus Master.
  17     Wait for DMA Bus Master to complete the write operation.
  18     Call DmaUnmap().
  19
  20   DMA Bus Master Common Buffer Operation:
  21     Call DmaAllocateBuffer() to allocate a common buffer.
  22     Call DmaMap() for MapOperationBusMasterCommonBuffer.
  23     Program the DMA Bus Master with the DeviceAddress returned by DmaMap().
  24     The common buffer can now be accessed equally by the processor and the DMA bus master.
  25     Call DmaUnmap().
  26     Call DmaFreeBuffer().
  27
  28   Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
  29
  30   SPDX-License-Identifier: BSD-2-Clause-Patent
  31
  32 **/
  33
  34 #ifndef __DMA_LIB_H__
  35 #define __DMA_LIB_H__
  36
  37 typedef enum {
  38   ///
  39   /// A read operation from system memory by a bus master.
  40   ///
  41   MapOperationBusMasterRead,
  42   ///
  43   /// A write operation from system memory by a bus master.
  44   ///
  45   MapOperationBusMasterWrite,
  46   ///
  47   /// Provides both read and write access to system memory by both the processor and a
  48   /// bus master. The buffer is coherent from both the processor's and the bus master's point of view.
  49   ///
  50   MapOperationBusMasterCommonBuffer,
  51   MapOperationMaximum
  52 } DMA_MAP_OPERATION;
  53
  54 /**
  55   Provides the DMA controller-specific addresses needed to access system memory.
  56
  57   Operation is relative to the DMA bus master.
  58
  59   @param  Operation             Indicates if the bus master is going to read or write to system memory.
  60   @param  HostAddress           The system memory address to map to the DMA controller.
  61   @param  NumberOfBytes         On input the number of bytes to map. On output the number of bytes
  62                                 that were mapped.
  63   @param  DeviceAddress         The resulting map address for the bus master controller to use to
  64                                 access the hosts HostAddress.
  65   @param  Mapping               A resulting value to pass to DmaUnmap().
  66
  67   @retval EFI_SUCCESS           The range was mapped for the returned NumberOfBytes.
  68   @retval EFI_UNSUPPORTED       The HostAddress cannot be mapped as a common buffer.
  69   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  70   @retval EFI_OUT_OF_RESOURCES  The request could not be completed due to a lack of resources.
  71   @retval EFI_DEVICE_ERROR      The system hardware could not map the requested address.
  72
  73 **/
  74 EFI_STATUS
  75 EFIAPI
  76 DmaMap (
  77   IN     DMA_MAP_OPERATION  Operation,
  78   IN     VOID               *HostAddress,
  79   IN OUT UINTN              *NumberOfBytes,
  80   OUT    PHYSICAL_ADDRESS   *DeviceAddress,
  81   OUT    VOID               **Mapping
  82   );
  83
  84 /**
  85   Completes the DmaMapBusMasterRead, DmaMapBusMasterWrite, or DmaMapBusMasterCommonBuffer
  86   operation and releases any corresponding resources.
  87
  88   @param  Mapping               The mapping value returned from DmaMap().
  89
  90   @retval EFI_SUCCESS           The range was unmapped.
  91   @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.
  92
  93 **/
  94 EFI_STATUS
  95 EFIAPI
  96 DmaUnmap (
  97   IN  VOID  *Mapping
  98   );
  99
 100 /**
 101   Allocates pages that are suitable for an DmaMap() of type MapOperationBusMasterCommonBuffer.
 102   mapping.
 103
 104   @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
 105                                 EfiRuntimeServicesData.
 106   @param  Pages                 The number of pages to allocate.
 107   @param  HostAddress           A pointer to store the base system memory address of the
 108                                 allocated range.
 109
 110                                 @retval EFI_SUCCESS           The requested memory pages were allocated.
 111   @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
 112                                 MEMORY_WRITE_COMBINE and MEMORY_CACHED.
 113   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
 114   @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
 115
 116 **/
 117 EFI_STATUS
 118 EFIAPI
 119 DmaAllocateBuffer (
 120   IN  EFI_MEMORY_TYPE  MemoryType,
 121   IN  UINTN            Pages,
 122   OUT VOID             **HostAddress
 123   );
 124
 125 /**
 126   Frees memory that was allocated with DmaAllocateBuffer().
 127
 128   @param  Pages                 The number of pages to free.
 129   @param  HostAddress           The base system memory address of the allocated range.
 130
 131   @retval EFI_SUCCESS           The requested memory pages were freed.
 132   @retval EFI_INVALID_PARAMETER The memory range specified by HostAddress and Pages
 133                                 was not allocated with DmaAllocateBuffer().
 134
 135 **/
 136 EFI_STATUS
 137 EFIAPI
 138 DmaFreeBuffer (
 139   IN  UINTN  Pages,
 140   IN  VOID   *HostAddress
 141   );
 142
 143 /**
 144   Allocates pages that are suitable for an DmaMap() of type
 145   MapOperationBusMasterCommonBuffer mapping, at the requested alignment.
 146
 147   @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
 148                                 EfiRuntimeServicesData.
 149   @param  Pages                 The number of pages to allocate.
 150   @param  Alignment             Alignment in bytes of the base of the returned
 151                                 buffer (must be a power of 2)
 152   @param  HostAddress           A pointer to store the base system memory address of the
 153                                 allocated range.
 154
 155   @retval EFI_SUCCESS           The requested memory pages were allocated.
 156   @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
 157                                 MEMORY_WRITE_COMBINE and MEMORY_CACHED.
 158   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
 159   @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
 160
 161 **/
 162 EFI_STATUS
 163 EFIAPI
 164 DmaAllocateAlignedBuffer (
 165   IN  EFI_MEMORY_TYPE  MemoryType,
 166   IN  UINTN            Pages,
 167   IN  UINTN            Alignment,
 168   OUT VOID             **HostAddress
 169   );
 170
 171 #endif