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Diffstat (limited to 'EmbeddedPkg/Include/Library/DmaLib.h')
| -rwxr-xr-x | EmbeddedPkg/Include/Library/DmaLib.h | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/EmbeddedPkg/Include/Library/DmaLib.h b/EmbeddedPkg/Include/Library/DmaLib.h new file mode 100755 index 0000000..badaf21 --- /dev/null +++ b/EmbeddedPkg/Include/Library/DmaLib.h @@ -0,0 +1,159 @@ +/** @file + DMA abstraction library APIs. Based on UEFI PCI IO protocol DMA abstractions. + At some point these functions will probably end up in a non PCI protocol + for embedded systems. + + DMA Bus Master Read Operation:
+ Call DmaMap() for MapOperationBusMasterRead. + Program the DMA Bus Master with the DeviceAddress returned by DmaMap(). + Start the DMA Bus Master. + Wait for DMA Bus Master to complete the read operation. + Call DmaUnmap(). + + DMA Bus Master Write Operation: + Call DmaMap() for MapOperationBusMasterWrite.
+ Program the DMA Bus Master with the DeviceAddress returned by DmaMap().
+ Start the DMA Bus Master.
+ Wait for DMA Bus Master to complete the write operation.
+ Call DmaUnmap(). + + DMA Bus Master Common Buffer Operation: + Call DmaAllocateBuffer() to allocate a common buffer. + Call DmaMap() for MapOperationBusMasterCommonBuffer. + Program the DMA Bus Master with the DeviceAddress returned by DmaMap(). + The common buffer can now be accessed equally by the processor and the DMA bus master. + Call DmaUnmap(). + Call DmaFreeBuffer(). + + Copyright (c) 2008 - 2010, Apple Inc. 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. + +**/ + +#ifndef __DMA_LIB_H__ +#define __DMA_LIB_H__ + +typedef enum {
+ ///
+ /// A read operation from system memory by a bus master.
+ ///
+ MapOperationBusMasterRead,
+ ///
+ /// A write operation from system memory by a bus master.
+ ///
+ MapOperationBusMasterWrite,
+ ///
+ /// Provides both read and write access to system memory by both the processor and a
+ /// bus master. The buffer is coherent from both the processor's and the bus master's point of view.
+ ///
+ MapOperationBusMasterCommonBuffer,
+ MapOperationMaximum
+} DMA_MAP_OPERATION;
+ + + + +/**
+ 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 DmaUnmap().
+
+ @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
+ ); + + + + +/**
+ 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
+ ); + + +/**
+ 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
+ );
+ + +/**
+ 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
+ );
+ + +#endif + |