A CSU DMA transfer is triggered after writing the size value for a DMA source channel. In the case of PL programming, there is only source channel. In the case of loopback, a DMA destination channel is configured first and then the source channel is configured.
The following steps are used to initiate a CSU DMA transfer.
1.Decide the channel type to be configured and set the address appropriately.
a.To configure the source channel, set the source address:
-Set the csudma.csudma_src_addr[addr] =
<LSB 30-bit source address (ignore the last 2 bits)>.
-Set the csudma.csudma_src_addr_msb[addr_msb] =
<MSB 16-bit source address>.
b.Else, set the destination address.
-Set the csudma.csudma_dst_addr[addr] =
<LSB 30-bit destination address (ignore last 2 bits)>.
-Set the csudma.csudma_src_addr_msb[addr_msb] =
<MSB 16-bit destination address>
2.Configure the source/destination size.
a.To configure the source channel:
Set the csudma.csudma_src_size[size] = <size of source buffer>.
b.Else,
Set csudma.csudma_dst_size[size] = <size of destination buffer>