28.11.15. alt_msgdma_construct_prefetcher_extended_mm_to_mm_descriptor
| Prototype: | int alt_msgdma_construct_prefetcher_extended_mm_to_mm_descriptor (alt_msgdma_dev *dev, alt_msgdma_prefetcher_extended_descriptor *descriptor, alt_u32 read_address_high, alt_u32 read_address_low, alt_u32 write_address_high, alt_u32 write_address_low, alt_u32 length, alt_u32 control, alt_u16 sequence_number, alt_u8 read_burst_count, alt_u8 write_burst_count, alt_u16 read_stride, alt_u16 write_stride); |
| Parameters: | *dev-a pointer to msgdma instance. *descriptor – a pointer to a standard descriptor structure. *read_address_high – a pointer to the high address of the source memory. *read_address_low – a pointer to the low address of the source memory. *write_address_high – a pointer to the high address of the destination memory. *write_address_low – a pointer to the low address of the destination memory. length – is used to specify the number of bytes to transfer per descriptor. The largest possible value can be filled in is “0Xffffffff”. control – control field. sequence_number – sequence number read_burst_count – read burst count write_burst_count – write burst count read_stride – read stride value write_stride – write stride value |
| Returns: | “0” for success. “-EINVAL” for invalid argument, could be due to argument which has larger value than hardware setting value. |
| Description: | Function will call helper function “alt_msgdma_construct_prefetcher_standard_descriptor” for constructing mm_to_mm standard descriptors. Unnecessary elements are set to 0 for completeness and will be ignored by the hardware. |