DMA extended descriptor.

The extended descriptor adds additional fields for the extended features available on the MMLDMA peripheral: destination interleaving and bufferable. The same three different DMA descriptors supported by the LDMA DMA controller are available. Each consists of seven WORDs (instead of four in non-extended descriptors) which map directly onto HW control registers for a given DMA channel. The three descriptor types are XFER, SYNC and WRI. But the extended fields are true only for XFER. The extended fields are the following: 

      +-          +- CTRL
      | Original  |  SRC
      | Structure |  DST

Extended | +- LINK Structure | XCTRL | Reserved for future usage +- ILSRC

Refer to the reference manual for further information.

Public Attributes#

uint32_t
structType

Set to 0 to select XFER descriptor type.

uint32_t
extend

Extend data structure.

uint32_t
structReq

DMA transfer trigger during LINKLOAD.

uint32_t
xferCnt

Transfer count minus one.

uint32_t
byteSwap

Enable byte swapping transfers.

uint32_t
blockSize

Number of unit transfers per arbitration cycle.

uint32_t
doneIfs

Generate interrupt when done.

uint32_t
reqMode

Block or cycle transfer selector.

uint32_t
decLoopCnt

Enable looped transfers.

uint32_t
ignoreSrec

Ignore single requests.

uint32_t
srcInc

Source address increment unit size.

uint32_t
size

DMA transfer unit size.

uint32_t
dstInc

Destination address increment unit size.

uint32_t
srcAddrMode

Source addressing mode.

uint32_t
dstAddrMode

Destination addressing mode.

uint32_t
srcAddr

DMA source address.

uint32_t
dstAddr

DMA destination address.

uint32_t
linkMode

Select absolute or relative link address.

uint32_t
link

Enable LINKLOAD when transfer is done.

int32_t
linkAddr

Address of next (linked) descriptor.

uint32_t
reserved1

Reserved

uint32_t
dstIlEn

Destination interleave.

uint32_t
IlMode

Interleave mode.

uint32_t
bufferable

Allow AHB buffering.

uint32_t
reserved2

Reserved

uint32_t
reserved3

Reserved

uint32_t
IlSrc

DMA rules table base address in memory.

Public Attribute Documentation#

structType#

uint32_t LDMA_DescriptorExtend_t::structType

Set to 0 to select XFER descriptor type.



extend#

uint32_t LDMA_DescriptorExtend_t::extend

Extend data structure.



structReq#

uint32_t LDMA_DescriptorExtend_t::structReq

DMA transfer trigger during LINKLOAD.



xferCnt#

uint32_t LDMA_DescriptorExtend_t::xferCnt

Transfer count minus one.



byteSwap#

uint32_t LDMA_DescriptorExtend_t::byteSwap

Enable byte swapping transfers.



blockSize#

uint32_t LDMA_DescriptorExtend_t::blockSize

Number of unit transfers per arbitration cycle.


doneIfs#

uint32_t LDMA_DescriptorExtend_t::doneIfs

Generate interrupt when done.



reqMode#

uint32_t LDMA_DescriptorExtend_t::reqMode

Block or cycle transfer selector.



decLoopCnt#

uint32_t LDMA_DescriptorExtend_t::decLoopCnt

Enable looped transfers.



ignoreSrec#

uint32_t LDMA_DescriptorExtend_t::ignoreSrec

Ignore single requests.



srcInc#

uint32_t LDMA_DescriptorExtend_t::srcInc

Source address increment unit size.



size#

uint32_t LDMA_DescriptorExtend_t::size

DMA transfer unit size.



dstInc#

uint32_t LDMA_DescriptorExtend_t::dstInc

Destination address increment unit size.



srcAddrMode#

uint32_t LDMA_DescriptorExtend_t::srcAddrMode

Source addressing mode.



dstAddrMode#

uint32_t LDMA_DescriptorExtend_t::dstAddrMode

Destination addressing mode.



srcAddr#

uint32_t LDMA_DescriptorExtend_t::srcAddr

DMA source address.



dstAddr#

uint32_t LDMA_DescriptorExtend_t::dstAddr

DMA destination address.



linkMode#

uint32_t LDMA_DescriptorExtend_t::linkMode

Select absolute or relative link address.



link#

uint32_t LDMA_DescriptorExtend_t::link

Enable LINKLOAD when transfer is done.



linkAddr#

int32_t LDMA_DescriptorExtend_t::linkAddr

Address of next (linked) descriptor.



reserved1#

uint32_t LDMA_DescriptorExtend_t::reserved1

Reserved


dstIlEn#

uint32_t LDMA_DescriptorExtend_t::dstIlEn

Destination interleave.



IlMode#

uint32_t LDMA_DescriptorExtend_t::IlMode

Interleave mode.



bufferable#

uint32_t LDMA_DescriptorExtend_t::bufferable

Allow AHB buffering.



reserved2#

uint32_t LDMA_DescriptorExtend_t::reserved2

Reserved


reserved3#

uint32_t LDMA_DescriptorExtend_t::reserved3

Reserved


IlSrc#

uint32_t LDMA_DescriptorExtend_t::IlSrc

DMA rules table base address in memory.