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   return EFI_SUCCESS;
  54 }
  55
  56
  57 /**
  58   Completes the DmaMapBusMasterRead(), DmaMapBusMasterWrite(), or DmaMapBusMasterCommonBuffer()
  59   operation and releases any corresponding resources.
  60
  61   @param  Mapping               The mapping value returned from DmaMap*().
  62
  63   @retval EFI_SUCCESS           The range was unmapped.
  64   @retval EFI_DEVICE_ERROR      The data was not committed to the target system memory.
  65
  66 **/
  67 EFI_STATUS
  68 EFIAPI
  69 DmaUnmap (
  70   IN  VOID                         *Mapping
  71   )
  72 {
  73   return EFI_SUCCESS;
  74 }
  75
  76 /**
  77   Allocates pages that are suitable for an DmaMap() of type MapOperationBusMasterCommonBuffer.
  78   mapping.
  79
  80   @param  MemoryType            The type of memory to allocate, EfiBootServicesData or
  81                                 EfiRuntimeServicesData.
  82   @param  Pages                 The number of pages to allocate.
  83   @param  HostAddress           A pointer to store the base system memory address of the
  84                                 allocated range.
  85
  86                                 @retval EFI_SUCCESS           The requested memory pages were allocated.
  87   @retval EFI_UNSUPPORTED       Attributes is unsupported. The only legal attribute bits are
  88                                 MEMORY_WRITE_COMBINE and MEMORY_CACHED.
  89   @retval EFI_INVALID_PARAMETER One or more parameters are invalid.
  90   @retval EFI_OUT_OF_RESOURCES  The memory pages could not be allocated.
  91
  92 **/
  93 EFI_STATUS
  94 EFIAPI
  95 DmaAllocateBuffer (
  96   IN  EFI_MEMORY_TYPE              MemoryType,
  97   IN  UINTN                        Pages,
  98   OUT VOID                         **HostAddress
  99   )
 100 {
 101   if (HostAddress == NULL) {
 102     return EFI_INVALID_PARAMETER;
 103   }
 104
 105   //
 106   // The only valid memory types are EfiBootServicesData and EfiRuntimeServicesData
 107   //
 108   // We used uncached memory to keep coherency
 109   //
 110   if (MemoryType == EfiBootServicesData) {
 111     *HostAddress = AllocatePages (Pages);
 112   } else if (MemoryType != EfiRuntimeServicesData) {
 113     *HostAddress = AllocateRuntimePages (Pages);
 114   } else {
 115     return EFI_INVALID_PARAMETER;
 116   }
 117
 118   return EFI_SUCCESS;
 119 }
 120
 121
 122 /**
 123   Frees memory that was allocated with DmaAllocateBuffer().
 124
 125   @param  Pages                 The number of pages to free.
 126   @param  HostAddress           The base system memory address of the allocated range.
 127
 128   @retval EFI_SUCCESS           The requested memory pages were freed.
 129   @retval EFI_INVALID_PARAMETER The memory range specified by HostAddress and Pages
 130                                 was not allocated with DmaAllocateBuffer().
 131
 132 **/
 133 EFI_STATUS
 134 EFIAPI
 135 DmaFreeBuffer (
 136   IN  UINTN                        Pages,
 137   IN  VOID                         *HostAddress
 138   )
 139 {
 140   if (HostAddress == NULL) {
 141      return EFI_INVALID_PARAMETER;
 142   }
 143
 144   FreePages (HostAddress, Pages);
 145   return EFI_SUCCESS;
 146 }
 147