}
};
-/************************* class IODBDMAMemoryCursor *************************/
-
-#if defined(__ppc__)
-
-struct IODBDMADescriptor;
-
-/*!
- @class IODBDMAMemoryCursor
- @abstract An IOMemoryCursor subclass that outputs a vector of DBDMA descriptors where the address and length are filled in.
- @discussion The IODBDMAMemoryCursor would be used when the DBDMA hardware is available for the device for that will use an instance of this cursor.
-*/
-class IODBDMAMemoryCursor : public IOMemoryCursor
-{
- OSDeclareDefaultStructors(IODBDMAMemoryCursor)
-
-public:
-/*! @function outputSegment
- @abstract Outpust the given segment into the output segments array in address and length fields of an DBDMA descriptor.
- @param segment The physical address and length that is next to be output.
- @param segments Base of the output vector of DMA address length pairs.
- @param segmentIndex Index to output 'segment' in the 'segments' array.
-*/
- static void outputSegment(PhysicalSegment segment,
- void * segments,
- UInt32 segmentIndex);
-
-/*! @defined dbdmaOutputSegment
- @discussion Backward compatibility define for the old global function definition. See IODBDMAMemoryCursor::outputSegment. */
-#define dbdmaOutputSegment IODBDMAMemoryCursor::outputSegment
-
-/*! @function withSpecification
- @abstract Creates and initializes an IODBDMAMemoryCursor in one operation.
- @discussion Factory function to create and initialize an IODBDMAMemoryCursor in one operation. See also IODBDMAMemoryCursor::initWithSpecification.
- @param maxSegmentSize Maximum allowable size for one segment. Defaults to 0.
- @param maxTransferSize Maximum size of an entire transfer. Defaults to 0 indicating no maximum.
- @param alignment Alignment restrictions on output physical addresses. Not currently implemented. Defaults to single byte alignment.
- @result Returns a new memory cursor if successfully created and initialized, 0 otherwise.
-*/
- static IODBDMAMemoryCursor *
- withSpecification(IOPhysicalLength maxSegmentSize,
- IOPhysicalLength maxTransferSize,
- IOPhysicalLength alignment = 1);
-
-/*! @function initWithSpecification
- @abstract Primary initializer for the IODBDMAMemoryCursor class.
- @param maxSegmentSize Maximum allowable size for one segment. Defaults to 0.
- @param maxTransferSize Maximum size of an entire transfer. Defaults to 0 indicating no maximum.
- @param alignment Alignment restrictions on output physical addresses. Not currently implemented. Defaults to single byte alignment.
- @result Returns true if the inherited classes and this instance initialize successfully.
-*/
- virtual bool initWithSpecification(IOPhysicalLength maxSegmentSize,
- IOPhysicalLength maxTransferSize,
- IOPhysicalLength alignment = 1);
-
-
-/*! @function getPhysicalSegments
- @abstract Generates a DBDMA physical scatter/gather list given a memory descriptor.
- @discussion Generates a list of DBDMA descriptors where the address and length fields are filled in appropriately. But the client is expected to fill in the rest of the DBDMA descriptor as is appropriate for their particular hardware. Wraps IOMemoryCursor::genPhysicalSegments.
- @param descriptor IOMemoryDescriptor that describes the data associated with an I/O request.
- @param fromPosition Starting location of the I/O within a memory descriptor.
- @param segments Pointer to an array of DBDMA descriptors for the output physical scatter/gather list. Be warned no room is left for a preamble in the output array. 'segments' should point to the first memory description slot in a DBDMA command.
- @param maxSegments Maximum number of segments that can be written to the DBDMA descriptor table.
- @param inMaxTransferSize Maximum transfer size is limited to that many bytes, otherwise it defaults to the maximum transfer size specified when the memory cursor was initialized.
- @param transferSize Pointer to an IOByteCount variable that can contain the total size of the transfer being described. Defaults to 0 indicating that no transfer size need be returned.
- @result If the descriptor is exhausted of memory, a zero is returned, otherwise the number of segments that were filled in is returned.
-*/
- virtual UInt32 getPhysicalSegments(IOMemoryDescriptor * descriptor,
- IOByteCount fromPosition,
- IODBDMADescriptor * segments,
- UInt32 maxSegments,
- UInt32 inMaxTransferSize = 0,
- IOByteCount * transferSize = 0)
- {
- return genPhysicalSegments(descriptor, fromPosition, segments,
- maxSegments, inMaxTransferSize, transferSize);
- }
-};
-
-#endif /* defined(__ppc__) */
-
#endif /* !_IOMEMORYCURSOR_H */
projects / apple / xnu.git / blobdiff