|
Mac Dev Center
 Mac OS X Reference Library Drivers, Kernel, & Hardware: Kernel Device Drivers Kernel Framework Reference
|
IODMACommand |
| Inherits from: | |
| Declared In: |
Overview
A mechanism to convert memory references to I/O bus addresses.
Discussion
The IODMACommand is supersedes the IOMemoryCursor and greatly enhances the functionality and power of it. The command can be specified to output 64 bit physical addresses and also allows driver writers bypass mapping hardware or get addresses suitable for non-snooped DMA.
Clears the DMACommand's current memory descriptor
Creates a new command based on the specification of the current one.
Complete processing of DMA mappings after an I/O transfer is finished.
Helper function for a type checked call to genIOVMSegments(qv), for use with an IODMACommand set up with the output function kIODMACommandOutputHost32, kIODMACommandOutputBig32, or kIODMACommandOutputLittle32. If the output function of the IODMACommand is not a 32 bit function, results will be incorrect.
Helper function for a type checked call to genIOVMSegments(qv), for use with an IODMACommand set up with the output function kIODMACommandOutputHost64, kIODMACommandOutputBig64, or kIODMACommandOutputLittle64. If the output function of the IODMACommand is not a 64 bit function, results will be incorrect.
Generates a physical scatter/gather for the current DMA command
Get the current memory descriptor
Returns the offset and length into the target IOMemoryDescriptor of a prepared IODDMACommand.
Primary initializer for the IODMACommand class.
Output big-endian Segment32 output segment function.
Output big-endian Segment64 output segment function.
Output host natural Segment32 output segment function.
Output host natural Segment64 output segment function.
Output little-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Prepare the memory for an I/O transfer.
Prepare the memory for an I/O transfer with a new specification.
Copy data from the IODMACommand's buffer to the specified buffer.
Sets and resets the DMACommand's current memory descriptor
Bring IOMemoryDescriptor and IODMACommand buffers into sync.
Creates and initialises an IODMACommand in one operation if this version of the operating system supports it.
Creates and initializes an IODMACommand in one operation.
Copy data to the IODMACommand's buffer from the specified buffer.
Clears the DMACommand's current memory descriptor
An optional boolean variable that will call the complete() function automatically before the memory descriptor is processed. Defaults to true. completes and invalidates the cache if the DMA command is currently active, copies all data from bounce buffers if necessary and releases all resources acquired during setMemoryDescriptor.
Creates a new command based on the specification of the current one.
Returns a new memory cursor if successfully created and initialised, 0 otherwise.
Factory function to create and initialise an IODMACommand in one operation. The current command's specification will be duplicated in the new object, but however none of its state will be duplicated. This means that it is safe to clone a command even if it is currently active and running, however you must be certain that the command to be duplicated does have a valid reference for the duration.
Complete processing of DMA mappings after an I/O transfer is finished.
Invalidate the caches for the memory descriptor. Defaults to true for kNonCoherent and is ignored by the other types. Copy any buffered data back to the target IOMemoryDescriptor. Defaults to true, if synchronize() is being used to explicitly copy data, passing false may avoid an unneeded copy. kIOReturnNotReady if not prepared, kIOReturnSuccess otherwise.
This method should not be called unless a prepare was previously issued; the prepare() and complete() must occur in pairs, before and after an I/O transfer
Helper function for a type checked call to genIOVMSegments(qv), for use with an IODMACommand set up with the output function kIODMACommandOutputHost32, kIODMACommandOutputBig32, or kIODMACommandOutputLittle32. If the output function of the IODMACommand is not a 32 bit function, results will be incorrect.
Helper function for a type checked call to genIOVMSegments(qv), for use with an IODMACommand set up with the output function kIODMACommandOutputHost64, kIODMACommandOutputBig64, or kIODMACommandOutputLittle64. If the output function of the IODMACommand is not a 64 bit function, results will be incorrect.
Generates a physical scatter/gather for the current DMA command
input/output parameter, defines the starting and ending offset in the memory descriptor, relative to any offset passed to the prepare() method. Void pointer to base of output physical scatter/gather list. Always passed directly onto the SegmentFunction. Input/output parameter Number of segments that can fit in the segment array and returns number of segments generated. kIOReturnSuccess on success, kIOReturnOverrun if the memory descriptor is exhausted, kIOReturnMessageTooLarge if the output segment function's address bits has insufficient resolution for a segment, kIOReturnNotReady if the DMA command has not be prepared, kIOReturnBadArgument if the DMA command doesn't have a memory descriptor yet or some of the parameters are NULL and kIOReturnNotReady if the DMA command is not prepared.
Generates a list of physical segments from the given memory descriptor, relative to the current position of the descriptor. The constraints that are set during initialisation will be respected. This function maintains the state across multiple calls for efficiency. However the state is discarded if the new offset is not the expected one.
Get the current memory descriptor
Returns the offset and length into the target IOMemoryDescriptor of a prepared IODDMACommand.
returns the starting offset in the memory descriptor the DMA command was prepared with. Pass NULL for don't care. returns the length in the memory descriptor the DMA command was prepared with. Pass NULL for don't care. An IOReturn code. kIOReturnNotReady if the IODMACommand is not prepared.
If successfully prepared, returns the offset and length into the IOMemoryDescriptor. Will fail for an unprepared IODMACommand.
Primary initializer for the IODMACommand class.
SegmentFunction to call to output one physical segment. A set of nine commonly required segment functions are provided. Number of bits that the hardware uses on its internal address bus. Typically 32 but may be more on modern hardware. A 0 implies no-restriction other than that implied by the output segment function. Maximum allowable size for one segment. Defaults to 0 which means any size. is the type of mapping that is required to translate an IOMemoryDescriptor into the desired number of bits. For instance if your hardware only supports 32 bits but must run on machines with > 4G of RAM some mapping will be required. Number of bits will be specified in numAddressBits, see below.This parameter can take 3 values:- kNonCoherent - used for non-coherent hardware transfers, Mapped - Validate that all I/O bus generated addresses are within the number of addressing bits specified, Bypassed indicates that bypassed addressing is required, this is used when the hardware transferes are into coherent memory but no mapping is required. See also prepare() for failure cases. Maximum size of an entire transfer. Defaults to 0 indicating no maximum. Alignment restriction, in bytes, on I/O bus addresses. Defaults to single byte alignment. For mapping types kMapped & kBypassed mapper is used to define the hardware that will perform the mapping, defaults to the system mapper. Can fail if the mapping type is not recognised, if one of the 3 mandatory parameters are set to 0, if a 32 bit output function is selected when more than 32 bits of address is required or, if kBypassed is requested on a machine that doesn't support bypassing. Returns true otherwise.
Output big-endian Segment32 output segment function.
Output big-endian Segment64 output segment function.
Output host natural Segment32 output segment function.
Output host natural Segment64 output segment function.
Output little-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Prepare the memory for an I/O transfer.
defines the starting offset in the memory descriptor the DMA command will operate on. genIOVMSegments will produce its results based on the offset and length passed to the prepare method. defines the ending position in the memory descriptor the DMA command will operate on. genIOVMSegments will produce its results based on the offset and length passed to the prepare method. Flush the caches for the memory descriptor and make certain that the memory cycles are complete. Defaults to true for kNonCoherent and is ignored by the other types. Copy any buffered data back from the target IOMemoryDescriptor. Defaults to true, if synchronize() is being used to explicitly copy data, passing false may avoid an unneeded copy. An IOReturn code.
Allocate the mapping resources neccessary for this transfer, specifying a sub range of the IOMemoryDescriptor that will be the target of the I/O. The complete() method frees these resources. Data may be copied to buffers for kIODirectionOut memory descriptors, depending on hardware mapping resource availabilty or alignment restrictions. It should be noted that the this function may block and should only be called on the clients context, i.e never call this routine while gated; also the call itself is not thread safe though this should be an issue as each IODMACommand is independant.
Prepare the memory for an I/O transfer with a new specification.
SegmentFunction to call to output one physical segment. A set of nine commonly required segment functions are provided. Number of bits that the hardware uses on its internal address bus. Typically 32 but may be more on modern hardware. A 0 implies no-restriction other than that implied by the output segment function. Maximum allowable size for one segment. Defaults to 0 which means any size. is the type of mapping that is required to translate an IOMemoryDescriptor into the desired number of bits. For instance if your hardware only supports 32 bits but must run on machines with > 4G of RAM some mapping will be required. Number of bits will be specified in numAddressBits, see below.This parameter can take 3 values:- kNonCoherent - used for non-coherent hardware transfers, Mapped - Validate that all I/O bus generated addresses are within the number of addressing bits specified, Bypassed indicates that bypassed addressing is required, this is used when the hardware transferes are into coherent memory but no mapping is required. See also prepare() for failure cases. Maximum size of an entire transfer. Defaults to 0 indicating no maximum. Alignment restriction, in bytes, on I/O bus addresses. Defaults to single byte alignment. For mapping types kMapped & kBypassed mapper is used to define the hardware that will perform the mapping, defaults to the system mapper. defines the starting offset in the memory descriptor the DMA command will operate on. genIOVMSegments will produce its results based on the offset and length passed to the prepare method. defines the ending position in the memory descriptor the DMA command will operate on. genIOVMSegments will produce its results based on the offset and length passed to the prepare method. Flush the caches for the memory descriptor and make certain that the memory cycles are complete. Defaults to true for kNonCoherent and is ignored by the other types. Copy any buffered data back from the target IOMemoryDescriptor. Defaults to true, if synchronize() is being used to explicitly copy data, passing false may avoid an unneeded copy. An IOReturn code. Can fail if the mapping type is not recognised, if one of the 3 mandatory parameters are set to 0, if a 32 bit output function is selected when more than 32 bits of address is required or, if kBypassed is requested on a machine that doesn't support bypassing.
Allocate the mapping resources neccessary for this transfer, specifying a sub range of the IOMemoryDescriptor that will be the target of the I/O. The complete() method frees these resources. Data may be copied to buffers for kIODirectionOut memory descriptors, depending on hardware mapping resource availabilty or alignment restrictions. It should be noted that the this function may block and should only be called on the clients context, i.e never call this routine while gated; also the call itself is not thread safe though this should be an issue as each IODMACommand is independant.
Copy data from the IODMACommand's buffer to the specified buffer.
A byte offset into the IODMACommand's memory, relative to the prepared offset. The caller supplied buffer to copy the data to. The length of the data to copy. The number of bytes copied, zero will be returned if the specified offset is beyond the prepared length of the IODMACommand.
This method copies data from the IODMACommand's memory at the given offset, to the caller's buffer. The IODMACommand must be prepared, and the offset is relative to the prepared offset.
Sets and resets the DMACommand's current memory descriptor
A pointer to the current I/Os memory descriptor. An optional boolean variable that will call the prepare() function automatically after the memory descriptor is processed. Defaults to true. Returns kIOReturnSuccess, kIOReturnBusy if currently prepared, kIOReturnNoSpace if the length(mem) >= Maximum Transfer Size or the error codes returned by prepare() (qv).
The DMA command will configure itself based on the information that it finds in the memory descriptor. It looks for things like the direction of the memory descriptor and whether the current memory descriptor is already mapped into some IOMMU. As a programmer convenience it can also prepare the memory descriptor immediately. See prepare(). Note the IODMACommand is designed to used multiple times with a succession of memory descriptors, making the pooling of commands possible. It is an error though to attempt to reset a currently prepared() DMA command. Warning: This routine may block so never try to autoprepare an IODMACommand while in a gated context, i.e. one of the WorkLoops action call outs.
Bring IOMemoryDescriptor and IODMACommand buffers into sync.
Specifies the direction of the copy:
kIODirectionOut copy IOMemoryDesciptor memory to any IODMACommand buffers. By default this action takes place automatically at prepare().
kIODirectionIn copy any IODMACommand buffers back to the IOMemoryDescriptor. By default this action takes place automatically at complete().
kForceDoubleBuffer copy the entire prepared range to a new page aligned buffer. kIOReturnNotReady if not prepared, kIOReturnBadArgument if invalid options are passed, kIOReturnSuccess otherwise.
This method should not be called unless a prepare was previously issued. If needed a caller may synchronize any IODMACommand buffers with the original IOMemoryDescriptor buffers.
Creates and initialises an IODMACommand in one operation if this version of the operating system supports it.
Output reference variable of the newly created IODMACommand. SegmentFunction to call to output one physical segment. A set of nine commonly required segment functions are provided. Number of bits that the hardware uses on its internal address bus. Typically 32 but may be more on modern hardware. A 0 implies no-restriction other than that implied by the output segment function. Maximum allowable size for one segment. Zero is treated as an unlimited segment size. is the type of mapping that is required to translate an IOMemoryDescriptor into the desired number of bits. For instance if your hardware only supports 32 bits but must run on machines with > 4G of RAM some mapping will be required. Number of bits will be specified in numAddressBits, see below. This parameter can take 3 values:- kNonCoherent - used for non-coherent hardware transfers, Mapped - Validate that all I/O bus generated addresses are within the number of addressing bits specified, Bypassed indicates that bypassed addressing is required, this is used when the hardware transfers are into coherent memory but no mapping is required. See also prepare() for failure cases. Maximum size of an entire transfer. Defaults to 0 indicating no maximum. Alignment restriction, in bytes, on I/O bus addresses. Defaults to single byte alignment. For mapping types kMapped & kBypassed mapper is used to define the hardware that will perform the mapping, defaults to the system mapper. kIOReturnSuccess if everything is OK, otherwise kIOReturnBadArgument if newCommand is NULL, kIOReturnUnsupported if the kernel doesn't export IODMACommand or IOReturnError if the new command fails to init, q.v. initWithSpecification.
Factory function to create and initialise an IODMACommand in one operation. The function allows a developer to 'weak' link with IODMACommand. This function will return kIOReturnUnsupported if the IODMACommand is unavailable. This function is actually fairly slow so it will be better to call it once then clone the successfully create command using cloneCommand (q.v.).
Creates and initializes an IODMACommand in one operation.
SegmentFunction to call to output one physical segment. A set of nine commonly required segment functions are provided. Number of bits that the hardware uses on its internal address bus. Typically 32 but may be more on modern hardware. A 0 implies no-restriction other than that implied by the output segment function. Maximum allowable size for one segment. If 0 is passed the maximum segment size is unlimited. is the type of mapping that is required to translate an IOMemoryDescriptor into the desired number of bits. For instance if your hardware only supports 32 bits but must run on machines with > 4G of RAM some mapping will be required. Number of bits will be specified in numAddressBits, see below.This parameter can take 3 values:- kNonCoherent - used for non-coherent hardware transfers, Mapped - Validate that all I/O bus generated addresses are within the number of addressing bits specified, Bypassed indicates that bypassed addressing is required, this is used when the hardware transferes are into coherent memory but no mapping is required. See also prepare() for failure cases. Maximum size of an entire transfer. Defaults to 0 indicating no maximum. Alignment restriction, in bytes, on I/O bus addresses. Defaults to single byte alignment. For mapping types kMapped & kBypassed mapper is used to define the hardware that will perform the mapping, defaults to the system mapper. Returns a new memory cursor if successfully created and initialized, 0 otherwise.
Factory function to create and initialize an IODMACommand in one operation.
Copy data to the IODMACommand's buffer from the specified buffer.
A byte offset into the IODMACommand's memory, relative to the prepared offset. The caller supplied buffer to copy the data from. The length of the data to copy. The number of bytes copied, zero will be returned if the specified offset is beyond the prepared length of the IODMACommand.
This method copies data to the IODMACommand's memory at the given offset, from the caller's buffer. The IODMACommand must be prepared, and the offset is relative to the prepared offset.
A 32 bit I/O bus address/length pair
A 32 bit I/O bus address/length pair
The 64Bit I/O bus address and length. Base of the output vector of DMA address length pairs. Index to output 'segment' in the 'segments' array. Returns true if segment encoding succeeded. false may be returned if the current segment does not fit in an output segment, i.e. a 38bit address wont fit into a 32 encoding.
Pointer to a C function that translates a 64 segment and outputs a single desired segment to the array at the requested index. There are a group of pre-implemented SegmentFunctions that may be usefull to the developer below.
A 32 bit I/O bus address/length pair
A 32 bit I/O bus address/length pair
fActive indicates that this DMA command is currently prepared and ready to go
Alignment restriction mask.
Mask to be ored into the address to bypass the given iommu's mapping.
Client defined mapper.
What type of I/O virtual address mapping is required for this command
Maximum size of one segment in a scatter/gather list Maximum size of a transfer that this memory cursor is allowed to generate
memory descriptor for current I/O.
Number of bits that the hardware can address
Number of contiguous segments required for the current memory descriptor and desired mapping
The action method called when an event has been delivered Reference Constant, client defined publicly avialable Reserved for future use. (Internal use only)
A 32 bit I/O bus address/length pair
A 32 bit I/O bus address/length pair
Output big-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Output big-endian Segment64 output segment function.
Output host natural Segment32 output segment function.
Output host natural Segment64 output segment function.
Output little-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Output big-endian Segment64 output segment function.
Output big-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Output big-endian Segment64 output segment function.
Output host natural Segment32 output segment function.
Output host natural Segment64 output segment function.
Output little-endian Segment32 output segment function.
Output little-endian Segment64 output segment function.
Output big-endian Segment64 output segment function.
Last Updated: 2009-10-14
The command is designed to be very easily subclassable. Most driver writers need to associate some DMA operations with their memory descriptor and usually use a C structure for that purpose. This structure is often kept in a linked list. This IODMACommand has built it
It is envisaged that a pool of IODMACommands will be created at driver initialisation and each command will be kept in an IOCommandPool while not in use. However if developers wishes to maintain their own free lists that is certainly possible. See the
The IODMACommand can be used in a 'weak-linked' manner. To do this you must avoid using any static member functions. Use the, much slower but safe, weakWithSpecification function. On success a dma command instance will be returned. This instance can then be used to clone as many commands as is needed. Remember deriving from this class can not be done weakly, that is no weak subclassing!
Functions
clearMemoryDescriptor
public
virtual IOReturn clearMemoryDescriptor(
bool autoComplete = true); Parameters
autoCompleteDiscussion
cloneCommand
public
virtual IODMACommand *cloneCommand(
void *refCon = 0); Return Value
Discussion
complete
public
virtual IOReturn complete(
bool invalidateCache = true,
bool synchronize = true); Parameters
invalidCachesynchronizeReturn Value
Discussion
gen32IOVMSegments
public
inline IOReturn gen32IOVMSegments(
UInt64 *offset,
Segment32 *segments,
UInt32 *numSegments) ;
gen64IOVMSegments
public
inline IOReturn gen64IOVMSegments(
UInt64 *offset,
Segment64 *segments,
UInt32 *numSegments) ;
genIOVMSegments
public
virtual IOReturn genIOVMSegments(
UInt64 *offset,
void *segments,
UInt32 *numSegments); Parameters
offsetsegmentsnumSegmentsReturn Value
Discussion
getMemoryDescriptor
public
virtual const IOMemoryDescriptor *getMemoryDescriptor() const;
getPreparedOffsetAndLength
public
virtual IOReturn getPreparedOffsetAndLength(
UInt64 *offset,
UInt64 *length); Parameters
offsetlengthReturn Value
Discussion
initWithSpecification
public
virtual bool initWithSpecification(
SegmentFunction outSegFunc,
UInt8 numAddressBits,
UInt64 maxSegmentSize,
MappingOptions mappingOptions = kMapped,
UInt64 maxTransferSize = 0,
UInt32 alignment = 1,
IOMapper *mapper = 0,
void *refCon = 0); Parameters
outSegFuncnumAddressBitsmaxSegmentSizemappingOptionsmaxTransferSizealignmentmapperReturn Value
OutputBig32
public
static bool OutputBig32(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
OutputBig64
public
static bool OutputBig64(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
OutputHost32
public
static bool OutputHost32(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
OutputHost64
public
static bool OutputHost64(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
OutputLittle32
public
static bool OutputLittle32(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
OutputLittle64
public
static bool OutputLittle64(
IODMACommand *target,
Segment64 seg,
void *segs,
UInt32 ind);
prepare
public
virtual IOReturn prepare(
UInt64 offset = 0,
UInt64 length = 0,
bool flushCache = true,
bool synchronize = true); Parameters
offsetlengthflushCachesynchronizeReturn Value
Discussion
prepareWithSpecification
public
virtual IOReturn prepareWithSpecification(
SegmentFunction outSegFunc,
UInt8 numAddressBits,
UInt64 maxSegmentSize,
MappingOptions mappingOptions = kMapped,
UInt64 maxTransferSize = 0,
UInt32 alignment = 1,
IOMapper *mapper = 0,
UInt64 offset = 0,
UInt64 length = 0,
bool flushCache = true,
bool synchronize = true); Parameters
outSegFuncnumAddressBitsmaxSegmentSizemappingOptionsmaxTransferSizealignmentmapperoffsetlengthflushCachesynchronizeReturn Value
Discussion
readBytes
public
UInt64 readBytes(
UInt64 offset,
void *bytes,
UInt64 length); Parameters
offsetbyteslengthReturn Value
Discussion
setMemoryDescriptor
public
virtual IOReturn setMemoryDescriptor(
const IOMemoryDescriptor *mem,
bool autoPrepare = true); Parameters
memautoPrepareReturn Value
Discussion
synchronize
public
virtual IOReturn synchronize(
IOOptionBits options); Parameters
optionsReturn Value
Discussion
weakWithSpecification
public
static inline IOReturn weakWithSpecification (
IODMACommand **newCommand,
SegmentFunction outSegFunc,
UInt8 numAddressBits,
UInt64 maxSegmentSize,
MappingOptions mapType = kMapped,
UInt64 maxTransferSize = 0,
UInt32 alignment = 1,
IOMapper *mapper = 0,
void *refCon = 0) __attribute__((always_inline)); Parameters
newCommandoutSegFuncnumAddressBitsmaxSegmentSizemapTypemaxTransferSizealignmentmapperReturn Value
Discussion
withSpecification
public
static IODMACommand * withSpecification(
SegmentFunction outSegFunc,
UInt8 numAddressBits,
UInt64 maxSegmentSize,
MappingOptions mappingOptions = kMapped,
UInt64 maxTransferSize = 0,
UInt32 alignment = 1,
IOMapper *mapper = 0,
void *refCon = 0); Parameters
outSegFuncnumAddressBitsmaxSegmentSizemappingOptionsmaxTransferSizealignmentmapperReturn Value
Discussion
writeBytes
public
UInt64 writeBytes(
UInt64 offset,
const void *bytes,
UInt64 length); Parameters
offsetbyteslengthReturn Value
Discussion
Typedefs
Segment32
See Also:
public
typedef bool ( *SegmentFunction)(
IODMACommand *target,
Segment64 segment,
void *segments,
UInt32 segmentIndex); Discussion
SegmentFunction
See Also:
public
typedef bool ( *SegmentFunction)(
IODMACommand *target,
Segment64 segment,
void *segments,
UInt32 segmentIndex); Discussion
SegmentFunction
public
typedef bool ( *SegmentFunction)(
IODMACommand *target,
Segment64 segment,
void *segments,
UInt32 segmentIndex); Parameters
segmentsegmentssegmentIndexReturn Value
Discussion
Structs and Unions
Segment32
See Also:
public
struct Segment32 {
UInt32 fIOVMAddr, fLength;
}; Discussion
Segment64
See Also:
public
struct Segment64 {
UInt64 fIOVMAddr, fLength;
}; Discussion
Member Data
fActive
protected
UInt32 fActive; Discussion
fAlignMask
protected
UInt32 fAlignMask; Discussion
fBypassMask
protected
UInt64 fBypassMask; Discussion
fMapper
protected
IOMapper *fMapper; Discussion
fMappingOptions
protected
MappingOptions fMappingOptions; Discussion
fMaxSegmentSize
protected
UInt64 fMaxSegmentSize; Discussion
fMaxTransferSize
protected
UInt64 fMaxTransferSize; Discussion
fMemory
protected
const IOMemoryDescriptor *fMemory; Discussion
fNumAddressBits
protected
UInt32 fNumAddressBits; Discussion
fNumSegments
protected
UInt32 fNumSegments; Discussion
fOutSeg
protected
SegmentFunction fOutSeg; Discussion
fRefCon
public
void *fRefCon; Discussion
reserved
protected
struct IODMACommandInternal * reserved; Discussion
Enumerated Types
MappingOptions
See Also:
public
enum MappingOptions {
kMapped = 0x00000000,
kBypassed = 0x00000001,
kNonCoherent = 0x00000002,
kTypeMask = 0x0000000f,
kNoCacheStore = 0x00000010, // Memory in descriptor
kOnChip = 0x00000020, // Indicates DMA is on South Bridge
kIterateOnly = 0x00000040 // DMACommand will be used as a cursor only
}; Discussion
SynchronizeOptions
See Also:
public
enum SynchronizeOptions {
kForceDoubleBuffer = 0x01000000
}; Discussion
Macro Definitions
kIODMACommandOutputBig32
#define kIODMACommandOutputBig32
kIODMACommandOutputBig64
#define kIODMACommandOutputBig64
kIODMACommandOutputBig64
#define kIODMACommandOutputLittle64
kIODMACommandOutputHost32
#define kIODMACommandOutputHost32
kIODMACommandOutputHost64
#define kIODMACommandOutputHost64
kIODMACommandOutputLittle32
#define kIODMACommandOutputLittle32
kIODMACommandOutputLittle64
#define kIODMACommandOutputBig64
kIODMACommandOutputLittle64
#define kIODMACommandOutputLittle64