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>
Add basic flow control to stream. A stream slave may return short, indicating
that it is not capable of accepting any more data at the present time. Polling
or a callback can be used via the can_push() function to determine when the
slave can receive again.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
If there is no DMA buffer descriptor, the DMA halts, not idles.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Create a separate child object to proxy the stream slave connection. This is
setup for future work where a second stream slave connection is needed. The
new child object is created at qdev init time and is linked back to the parent
(the ethernet device itself) automatically.
Stream slave masters differentiate which slave connection they are connected to
by linking to the proxy object rather than the parent.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
The prescribed transition from SysBusDevice::init to Device::realize. I'm going
with Andreas suggestion to move the sysbus foo to Object::init for early IRQ
visibility.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Register the reset function as the Device::reset function rather than
explicitly call it from the sysbus::init.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Standard QOM cast macro. Replaces usages of FROM_SYSBUS
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Typedef xilinx_axidma's object state struct to shorten the repeated usages of
struct XilinxAXIDMA.
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
