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.
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 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! Alex Marginean (3): drivers: net: Add a driver for the Felix Ethernet switch on NXP LS1028A arm: dts: ls1028a: add node for the integrated Ethernet switch configs: ls1028a: enable FSL_FELIX switch driver arch/arm/dts/fsl-ls1028a-rdb.dts | 36 ++ arch/arm/dts/fsl-ls1028a.dtsi | 31 ++ configs/ls1028aqds_tfa_SECURE_BOOT_defconfig | 1 + configs/ls1028aqds_tfa_defconfig | 1 + configs/ls1028ardb_tfa_SECURE_BOOT_defconfig | 1 + configs/ls1028ardb_tfa_defconfig | 1 + drivers/net/Kconfig | 7 + drivers/net/Makefile | 1 + drivers/net/fsl_enetc.h | 5 + drivers/net/fsl_felix.c | 421 +++++++++++++++++++ 10 files changed, 505 insertions(+) create mode 100644 drivers/net/fsl_felix.c -- 2.17.1 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
