tree b5a92b065b5550fcf4616553fedd906324918e75
parent 35e60bfdbc14ce31bba55cc82144f8a2a82ede68
author Peter Crosthwaite <peter.crosthwaite@xilinx.com> 1366072075 +1000
committer Edgar E. Iglesias <edgar.iglesias@gmail.com> 1366099463 +0200

xilinx_axienet/dma: Implement rx path flow control

Implement flow control for the RX data path from xilinx_axienet->xilinx_axidma.
On short return from axidma, then ethernet sets up the notify callback to resume
transfer from where it left off.

This also allows the ethernet to track whether there is an in progress transaction
and return false from ethernet can_receive() as appropriate.

If the DMA backs up or is disabled it waits for enablement. When the rx stream IO
region is touched, the can_push() notify function is called if set.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>