EmbeddedPkg/Library/NullDmaLib/NullDmaLib.c

   1 /** @file
   2   Generic ARM implementation of DmaLib.h
   3
   4   Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
   5
   6   This program and the accompanying materials
   7   are licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #include <Uefi.h>
  17 #include <Library/DebugLib.h>
  18 #include <Library/DmaLib.h>
  19 #include <Library/MemoryAllocationLib.h>
  20
  21
  22
  23 /**
  24   Provides the DMA controller-specific addresses needed to access system memory.
  25
  26   Operation is relative to the DMA bus master.
  27
  28   @param  Operation             Indicates if the bus master is going to read or write to system memory.
  29   @param  HostAddress           The system memory address to map to the DMA controller.
  30   @param  NumberOfBytes         On input the number of bytes to map. On output the number of bytes
  31                                 that were mapped.
  32   @param  DeviceAddress         The resulting map address for the bus master controller to use to
  33                                 access the hosts HostAddress.
  34   @param  Mapping               A resulting value to pass to Unmap().
  35
  36   @retval EFI_SUCCESS           The range was mapped for the returned NumberOfBytes.
  37   @retval EFI_UNSUPPORTED       The HostAddress cannot be mapped as a common buffer.
  38   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  39   @retval EFI_OUT_OF_RESOURCES  The request could not be completed due to a lack of resources.
  40   @retval EFI_DEVICE_ERROR      The system hardware could not map the requested address.
  41
  42 **/
  43 EFI_STATUS
  44 EFIAPI
  45 DmaMap (
  46   IN     DMA_MAP_OPERATION              Operation,
  47   IN     VOID                           *HostAddress,
  48   IN OUT UINTN                          *NumberOfBytes,
  49   OUT    PHYSICAL_ADDRESS               *DeviceAddress,
  50   OUT    VOID                           **Mapping
  51   )
  52 {
  53   *DeviceAddress = (PHYSICAL_ADDRESS)(UINTN)HostAddress;
  54   *Mapping = NULL;
  55   return EFI_SUCCESS;
  56 }
  57
  58
  59 /**
  60   Completes the DmaMapBusMasterRead(), DmaMapBusMasterWrite(), or DmaMapBusMasterCommonBuffer()
  61   operation and releases any corresponding resources.
  62
  63   @param  Mapping               The mapping value returned from DmaMap*().
  64
  65   @retval EFI_SUCCESS           The range was unmapped.
  66   @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.
  67
  68 **/
  69 EFI_STATUS
  70 EFIAPI
  71 DmaUnmap (
  72   IN  VOID                         *Mapping
  73   )
  74 {
  75   return EFI_SUCCESS;
  76 }
  77
  78 /**
  79   Allocates pages that are suitable for an DmaMap() of type MapOperationBusMasterCommonBuffer.
  80   mapping.
  81
  82   @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
  83                                 EfiRuntimeServicesData.
  84   @param  Pages                 The number of pages to allocate.
  85   @param  HostAddress           A pointer to store the base system memory address of the
  86                                 allocated range.
  87
  88                                 @retval EFI_SUCCESS           The requested memory pages were allocated.
  89   @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
  90                                 MEMORY_WRITE_COMBINE and MEMORY_CACHED.
  91   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  92   @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
  93
  94 **/
  95 EFI_STATUS
  96 EFIAPI
  97 DmaAllocateBuffer (
  98   IN  EFI_MEMORY_TYPE              MemoryType,
  99   IN  UINTN                        Pages,
 100   OUT VOID                         **HostAddress
 101   )
 102 {
 103   if (HostAddress == NULL) {
 104     return EFI_INVALID_PARAMETER;
 105   }
 106
 107   //
 108   // The only valid memory types are EfiBootServicesData and EfiRuntimeServicesData
 109   //
 110   // We used uncached memory to keep coherency
 111   //
 112   if (MemoryType == EfiBootServicesData) {
 113     *HostAddress = AllocatePages (Pages);
 114   } else if (MemoryType != EfiRuntimeServicesData) {
 115     *HostAddress = AllocateRuntimePages (Pages);
 116   } else {
 117     return EFI_INVALID_PARAMETER;
 118   }
 119
 120   return EFI_SUCCESS;
 121 }
 122
 123
 124 /**
 125   Frees memory that was allocated with DmaAllocateBuffer().
 126
 127   @param  Pages                 The number of pages to free.
 128   @param  HostAddress           The base system memory address of the allocated range.
 129
 130   @retval EFI_SUCCESS           The requested memory pages were freed.
 131   @retval EFI_INVALID_PARAMETER The memory range specified by HostAddress and Pages
 132                                 was not allocated with DmaAllocateBuffer().
 133
 134 **/
 135 EFI_STATUS
 136 EFIAPI
 137 DmaFreeBuffer (
 138   IN  UINTN                        Pages,
 139   IN  VOID                         *HostAddress
 140   )
 141 {
 142   if (HostAddress == NULL) {
 143      return EFI_INVALID_PARAMETER;
 144   }
 145
 146   FreePages (HostAddress, Pages);
 147   return EFI_SUCCESS;
 148 }
 149