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Description
To be documented
Constants
To be documented
Type definitions
To be documented
Public variables
To be documented
Function declarations
Initialization functions
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procedure DMAInit;
Description: To be documented
DMA host functions
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function DMAHostStart(DMA:PDMAHost):LongWord;
Description: To be documented
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function DMAHostStop(DMA:PDMAHost):LongWord;
Description: To be documented
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function DMAHostReset(DMA:PDMAHost):LongWord;
Description: To be documented
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function DMAHostProperties(DMA:PDMAHost; Properties:PDMAProperties):LongWord;
Description: To be documented
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function DMAHostCreate:PDMAHost;
Description: Create a new DMA entry
| Return
|
Pointer to new DMA entry or nil if DMA could not be created
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function DMAHostCreateEx(Size:LongWord):PDMAHost;
Description: Create a new DMA entry
| Size
|
Size in bytes to allocate for new DMA (Including the DMA entry")
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| Return
|
Pointer to new DMA entry or nil if DMA could not be created
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function DMAHostDestroy(DMA:PDMAHost):LongWord;
Description: Destroy an existing DMA entry
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function DMAHostRegister(DMA:PDMAHost):LongWord;
Description: Register a new DMA in the DMA host table
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function DMAHostDeregister(DMA:PDMAHost):LongWord;
Description: Deregister a DMA from the DMA host table
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function DMAHostFind(DMAId:LongWord):PDMAHost;
Description: To be documented
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function DMAHostEnumerate(Callback:TDMAEnumerate; Data:Pointer):LongWord;
Description: To be documented
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function DMAHostNotification(DMA:PDMAHost; Callback:TDMANotification; Data:Pointer; Notification,Flags:LongWord):LongWord;
Description: To be documented
DMA data functions
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function DMADataCount(Data:PDMAData):LongWord;
Description: Return the total number of data blocks in the linked list
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function DMADataFlags(Data:PDMAData):LongWord;
Description: Return the combined flags of the data blocks in the linked list
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function DMADataMaximum(Data:PDMAData):LongWord;
Description: Return the size of the largest data block in the linked list
DMA buffer functions
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function DMABufferAllocate(DMA:PDMAHost; Size:LongWord):Pointer; inline;
Description: Allocate a data buffer for a DMA request
| DMA
|
The DMA host that the request will be sent to
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| Size
|
The size of the data buffer to allocate
|
| Return
|
The newly allocated buffer or nil on failure
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function DMABufferAllocateEx(DMA:PDMAHost; var Size:LongWord):Pointer;
Description: Allocate a data buffer for a DMA request
| DMA
|
The DMA host that the request will be sent to
|
| Size
|
The size of the data buffer to allocate (Updated on return to actual size)
|
| Return
|
The newly allocated buffer or nil on failure
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| Note
|
This differs from DMABufferAllocate in that it updates the size value to reflect the actual size of the buffer allocated which may be required for some uses
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function DMABufferValidate(DMA:PDMAHost; Buffer:Pointer; Size:LongWord):LongWord;
Description: Validate a data buffer for a DMA request against the DMA host requirements
| DMA
|
The DMA host that the request will be sent to
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| Buffer
|
The data buffer to validate
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| Size
|
The size of the data buffer
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| Return
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ERROR_SUCCESS on success or another error code on failure (ERROR_NOT_COMPATIBLE if not compatible with host)
|
| Note
|
Does not check for cache coherency requirements (Shared, Non Cached) only alignment and size. Buffers used as the source of a DMA request do not neccessarily need to meet alignment and size requirements, however buffers used as a destintation must meet these requirements or the caller must take appropriate actions to prevent undesiraable side effects from cache invalidation.
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function DMABufferRelease(Buffer:Pointer):LongWord;
Description: Release a data buffer from a DMA request
| Data
|
The buffer to be released
|
| Return
|
ERROR_SUCCESS on success or another error code on failure
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DMA request functions
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function DMARequestAllocate(DMA:PDMAHost; Data:PDMAData; Callback:TDMARequestCompleted; DriverData:Pointer; Direction,Peripheral,Flags:LongWord):PDMARequest;
Description: Allocate a new DMA request
| DMA
|
The DMA host this request will be sent to
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| Data
|
A linked list of DMA data blocks for the transfer (Optional)
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| Callback
|
The callback function to be called on completion of the request
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| DriverData
|
Driver private data for the callback (Optional)
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| Direction
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The direction of the DMA request (eg DMA_DIR_MEM_TO_MEM)
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| Peripheral
|
The peripheral ID for data request gating (eg DMA_DREQ_ID_NONE)
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| Flags
|
Additional flags for this request (eg DMA_REQUEST_FLAG_CYCLIC)
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| Return
|
The newly allocated request or nil on failure
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function DMARequestRelease(Request:PDMARequest):LongWord;
Description: Release and destroy a DMA request
| Request
|
The request to be released
|
| Return
|
ERROR_SUCCESS on success or another error code on failure
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function DMARequestSubmit(Request:PDMARequest):LongWord;
Description: Submit a DMA request to a DMA host
| Request
|
The request to be submitted
|
| Return
|
ERROR_SUCCESS if completed or another error code on failure
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| Note
|
The request will be completed asynchronously by the DMA host and the completion callback will be called when the request has either succeeded or failed
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function DMARequestCancel(Request:PDMARequest):LongWord;
Description: Cancel a DMA request previously submitted to a DMA host
| Request
|
The request to be cancelled
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| Return
|
ERROR_SUCCESS if completed or another error code on failure
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procedure DMARequestComplete(Request:PDMARequest);
Description: Called by a DMA host when a DMA request completes
| Request
|
The DMA request which has completed
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| Note
|
DMA host drivers may call this on a worker thread
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DMA transfer functions
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function DMATransferRequest(DMA:PDMAHost; Data:PDMAData; Direction,Peripheral,Flags,Timeout:LongWord):LongWord;
Description: Perform a DMA transfer request with the supplied data blocks on the supplied host
| DMA
|
The DMA host to execute the request on
|
| Data
|
A linked list of DMA data blocks for the transfer
|
| Direction
|
The direction of the DMA request (eg DMA_DIR_MEM_TO_MEM)
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| Peripheral
|
The peripheral ID for data request gating (eg DMA_DREQ_ID_NONE)
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| Flags
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Additional flags for this transfer request (eg DMA_REQUEST_FLAG_CYCLIC)
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| Timeout
|
Milliseconds to wait for request to complete (INFINITE to wait forever)
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| Note
|
An internal callback will be specified and the function will wait for the transfer to complete
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function DMATransferRequestEx(DMA:PDMAHost; Data:PDMAData; Callback:TDMARequestCompleted; DriverData:Pointer; Direction,Peripheral,Flags:LongWord):LongWord;
Description: Perform a DMA transfer request with the supplied data blocks on the supplied host
| DMA
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The DMA host to execute the request on
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| Data
|
A linked list of DMA data blocks for the transfer
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| Callback
|
The callback function to be called on completion of the request
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| DriverData
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Driver private data for the callback (Optional)
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| Direction
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The direction of the DMA request (eg DMA_DIR_MEM_TO_MEM)
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| Peripheral
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The peripheral ID for data request gating (eg DMA_DREQ_ID_NONE)
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| Flags
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Additional flags for this transfer request (eg DMA_REQUEST_FLAG_CYCLIC)
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| Note
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The request will be passed to the callback with the DriverData field set to the DriverData passed to this function. On completion of the callback the request will automatically be released by the internal callback handler.
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RTL DMA functions
DMA helper functions
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