P4080 PCIe Adapter SDK User Guide Production Release

}
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u32 nlnda;
u32 bcount;
u32 rsvd;
s_attr – Source transaction attributes
s_addr – Source address of the DMA transfer
d_attr – Destination transaction attributes
d_addr – Destination attributes of the DMA transfer
nlndea – Points to the next link descriptor in memory. After the DMA controller reads the
link descriptor from memory, this field is loaded into the extended next link descriptor
address register.
nlnda – Points to the next link descriptor in memory. After the DMA controller reads the
link descriptor from memory, this field is loaded into the next link descriptor address
register.
bcount – Contains the number of bytes to transfer
rsvd – Reserved field
/**
* API: dma_ring_free – Release memory allocated for DMA ring.
*
* @dring – Pointer to the DMA ring of type “struct dma_ring”
*
* @return – SUCCESS (0) on successful cleanup, otherwise ERROR (1)
*/
The prototype of this API is as follows.
int dma_ring_free(struct dma_ring *dring);
dring – Pointer to DMA ring that needs to be freed. This memory is taken from the DMA
memory (64MB) on P4080.
/**
* API: dma_ring_enq – Enqueues a DMA job to the DMA ring. It picks
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