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SubjectRe: [PATCH net-next 3/5] net: bcmasp: Add support for ASP2.0 Ethernet controller
> > > +static int bcmasp_set_priv_flags(struct net_device *dev, u32 flags)
> > > +{
> > > + struct bcmasp_intf *intf = netdev_priv(dev);
> > > +
> > > + intf->wol_keep_rx_en = flags & BCMASP_WOL_KEEP_RX_EN ? 1 : 0;
> > > +
> > > + return 0;
> >
> > Please could you explain this some more. How can you disable RX and
> > still have WoL working?
>
> Wake-on-LAN using Magic Packets and network filters requires keeping the
> UniMAC's receiver turned on, and then the packets feed into the Magic Packet
> Detector (MPD) block or the network filter block. In that mode DRAM is in
> self refresh and there is local matching of frames into a tiny FIFO however
> in the case of magic packets the packets leading to a wake-up are dropped as
> there is nowhere to store them. In the case of a network filter match (e.g.:
> matching a multicast IP address plus protocol, plus source/destination
> ports) the packets are also discarded because the receive DMA was shut down.
>
> When the wol_keep_rx_en flag is set, the above happens but we also allow the
> packets that did match a network filter to reach the small FIFO (Justin
> would know how many entries are there) that is used to push the packets to
> DRAM. The packet contents are held in there until the system wakes up which
> is usually just a few hundreds of micro seconds after we received a packet
> that triggered a wake-up. Once we overflow the receive DMA FIFO capacity
> subsequent packets get dropped which is fine since we are usually talking
> about very low bit rates, and we only try to push to DRAM the packets of
> interest, that is those for which we have a network filter.
>
> This is convenient in scenarios where you want to wake-up from multicast DNS
> (e.g.: wake on Googlecast, Bonjour etc.) because then the packet that
> resulted in the system wake-up is not discarded but is then delivered to the
> network stack.

Thanks for the explanation. It would be easier for the user if you
automate this. Enable is by default for WoL types which have user
content?

> > > + /* Per ch */
> > > + intf->tx_spb_dma = priv->base + TX_SPB_DMA_OFFSET(intf);
> > > + intf->res.tx_spb_ctrl = priv->base + TX_SPB_CTRL_OFFSET(intf);
> > > + /*
> > > + * Stop gap solution. This should be removed when 72165a0 is
> > > + * deprecated
> > > + */
> >
> > Is that an internal commit?
>
> Yes this is a revision of the silicon that is not meant to see the light of
> day.

So this can all be removed?

Andrew

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