Hi Alex, On Fri, Nov 15, 2019 at 8:57 PM Alex Marginean <alexandru.margin...@nxp.com> wrote: > > The driver sets up the switch during probe making external and internal ports > available to use. It does not support direct I/O through these switch ports > in this version, instead ENETC ethernet interfaces that are internally linked > to > the switch can be used after the switch is set up. >
Thanks for the efforts! > This is where the RFC part comes in. Both the switch as a device and its > ports > are probed as ethernet devices. That's handy as accessors to connect to the > PHY > can be used on switch ports, but otherwise they are useless as the user can't > ping to these interfaces directly. We're not running STP in U-Boot either, so > turning on the switch is a problem if there are loops in the network. > The Linux driver for this piece of HW is now moving under DSA and this leads > to > my question. Does anyone here think that DSA support is something useful in > U-Boot? > > DSA is described here: > https://www.kernel.org/doc/Documentation/networking/dsa/dsa.txt > > From the doc: > > Summarized, this is basically how DSA looks like from a network device > perspective: > > > |--------------------------- > | CPU network device (eth0)| > ---------------------------- > | <tag added by switch | > | | > | | > | tag added by CPU> | > |--------------------------------------------| > | Switch driver | > |--------------------------------------------| > || || || > |-------| |-------| |-------| > | sw0p0 | | sw0p1 | | sw0p2 | > |-------| |-------| |-------| > > > If we do DSA in U-Boot we would use the same bindings as in Linux. The switch From the perspective of reusing the same bindings as Linux, yes, I would like to see the same DSA support in U-Boot :) > would be associated with a master network device which is a regular ethernet, > this is part of the DSA binding in Linux. > Whenever the user pings through swp0pN in background that would _start swp0pN, > the switch port connected to the master network device and the master network > device (eth0 in the picture above). Any frames sent through a switch port > would > have the DSA tag inserted and then actually sent though the mater network > device. Similarly for Rx, polling swp0pN would in fact poll on the master > network device and for any frame received the DSA code would check and remove > the DSA tag. > Switching between switch ports would be by default disabled. > This kind of switch drivers should go under a new class, DSA or ETH_DSA, or > something along those lines. > > I'd like to get some feedback from networking people on this list, if adding > DSA > support in U-Boot is something that could be useful, or the existing support > is > good enough. Currently U-Boot does support a few switches either as PHYs or > as ETH devices with various limitations. Feel free to share any thoughts on > this topic. > > With these patches applied the switch on LS1028A looks like this: > > => dm tree > Class Index Probed Driver Name > ----------------------------------------------------------- > .... > pci 2 [ + ] pci_generic_ecam |-- pcie@1f0000000 > eth 1 [ + ] enetc_eth | |-- enetc-0 > eth 2 [ + ] enetc_eth | |-- enetc-1 > eth 3 [ + ] enetc_eth | |-- enetc-2 > mdio 5 [ + ] enetc_mdio | |-- emdio-3 > pci_generi 0 [ ] pci_generic_drv | |-- pci_3:0.4 > eth 4 [ + ] felix_ethsw | |-- felix_ethsw > eth 6 [ + ] felix-port | | |-- port@0 > eth 7 [ + ] felix-port | | |-- port@1 > eth 8 [ + ] felix-port | | |-- port@2 > eth 9 [ + ] felix-port | | |-- port@3 > eth 10 [ + ] felix-port | | |-- port@4 > eth 11 [ + ] felix-port | | `-- port@5 > eth 5 [ + ] enetc_eth | |-- enetc-6 > pci_generi 1 [ ] pci_generic_drv | `-- pci_3:1f.0 > > => mdio list > felix_ethsw: > emdio-3: > mdio@50: > 0 - Aquantia AQR412 <--> port@0 > 1 - Aquantia AQR412 <--> port@1 > 2 - Aquantia AQR412 <--> port@2 > 3 - Aquantia AQR412 <--> port@3 > mdio@00: > 5 - AR8035 <--> enetc-1 > mdio@40: > 2 - Aquantia AQR112 <--> enetc-0 > mdio@60: > mdio@70: > > Any feedback is welcome, of course > > > This patch set replaces this v2 series: > https://patchwork.ozlabs.org/project/uboot/list/?series=126977&state=* > and depends on: > https://patchwork.ozlabs.org/project/uboot/list/?series=142858 > https://patchwork.ozlabs.org/project/uboot/list/?series=142879 > > Thank you! Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
