On Fri, Mar 22, 2024 at 7:21 PM Thomas Monjalon <tho...@monjalon.net> wrote: > > 22/03/2024 06:51, Jerin Jacob: > > On Fri, Mar 22, 2024 at 10:56 AM Ajit Khaparde > > <ajit.khapa...@broadcom.com> wrote: > > > > > > On Thu, Mar 21, 2024 at 9:39 PM Jerin Jacob <jerinjac...@gmail.com> wrote: > > > > > > > > On Fri, Mar 22, 2024 at 7:58 AM huangdengdui <huangdeng...@huawei.com> > > > > wrote: > > > > > > > > > > > > > > >
> > > > For example, If FW configures, 100G port as 100GBASE-SR2 then two > > > > ethdev(port 0 and port1) will show up. > > > > Now, assume if we expose this API and Can end user configure port 1 as > > > > 25G lines if so, > > > > a) What happens to port0 and it states? > > > There should be no impact to port0. > > > > > > > b) Will port2, port3 will show up after issuing this API(As end user > > > > configured 25Gx4 for 100G)? Will application needs to hotplug to get > > > > use ports. > > > No. The port count does not change. Nor does the number of PCI > > > functions seen by the host. Unless designed otherwise. > > > > > > Changing the lane count does not change anything in physical terms. > > > What changes is the modulation or the signaling scheme. > > > The number of lanes which can be supported is determined by > > > the PHY itself and the cables used and needs to be negotiated > > > appropriately > > > with the remote partner - which is just like using forced Ethernet Speed > > > instead of auto-negotiated speeds. > > Thanks for the explanation Ajit. > > > OK. It looks like platform independent then. At least cnxk driver, End > > user cannot simplify change the line config parameters > > while traffic is active also, it looks like other drivers need to have > > SerDes training with remote partner while reconfiguring it. > > > > At least on cnxk platform, 25Gx4 on 100G will show as 4 ethdev devices. > > That's a strange behaviour. > Why showing 4 ports which are not independent? I checked SerDes + NIC configuration again. It supports both modes. Show up as One port vs four ports. > > > Having said that, If other NICs support this feature without > > disturbing current port states, I don't have an objection to this API. > > >
