Hi Alex,
Am 2019-12-11 16:37, schrieb Alexandru Marginean:
On 12/11/2019 2:16 PM, Michael Walle wrote:
Hi Vladimir,
Am 2019-12-11 13:46, schrieb Vladimir Oltean:
Hi Michael,
On Wed, 11 Dec 2019 at 00:48, Michael Walle michael@walle.cc wrote:
Am 2019-12-10 15:55, schrieb Alex Marginean:
Passes on the primary address used by u-boot to Linux. The code does a DT fix-up for ENETC PFs and sets the primary MAC address in IERB. The address in IERB is restored on ENETC PCI functions at FLR.
I don't get the reason why this is done in a proprietary way. What is the difference between any other network interface whose hardware address is set up in the generic u-boot code.
Also, shouldn't write_hwaddr callback be implemented instead of the enetc_set_ierb_primary_mac()?
At the moment, the Linux driver ignored the device tree and only reads the POR values of the SIPMAR registers. The reset value of those comes from the IERB space, which U-Boot is configuring. So it would be good if that behavior keeps working.
It would also be good if the Linux driver called of_get_mac_address, so it needs the device tree binding for that. That's why both fixups are performed, and why the generic function is not used.
yes, but u-boot already sets the mac-address/local-mac-address property in the device tree already in a generic way, see fdt_fixup_ethernet().
I think fdt_fixup_ethernet is not a good choice for us. The issue is that it ties Linux DT to device indexes in U-Boot. That's a problem if we plug an Eth PCI card in, we would need to change Linux DT, which is definitely not desirable. We actually do use PCI Eth cards with some of our boards and U-Boot does pick those up and indexes shift.
are you sure? afaik it works by reading the /alias/ethernetN phandles which gets ethNaddr assigned if you set the FDT_SEQ_MACADDR_FROM_ENV config option. I've just tried it, here is my linux dts diff
--- a/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi +++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi @@ -17,6 +17,11 @@ #address-cells = <2>; #size-cells = <2>;
+ aliases { + ethernet0 = &enetc_port0; + ethernet1 = &enetc_port1; + }; + cpus { #address-cells = <1>; #size-cells = <0>; @@ -761,10 +766,12 @@ enetc_port0: ethernet@0,0 { compatible = "fsl,enetc"; reg = <0x000000 0 0 0 0>; + local-mac-address = [ 00 00 00 00 00 00 ]; }; enetc_port1: ethernet@0,1 { compatible = "fsl,enetc"; reg = <0x000100 0 0 0 0>; + local-mac-address = [ 00 00 00 00 00 00 ]; }; enetc_mdio_pf3: mdio@0,3 { compatible = "fsl,enetc-mdio";
That way the mapping between ethNaddr and the network device can also be changed by the user by changing the linux device tree.
also, uboot should respect the /aliases/ethernetN, too.
BTW what will be the source of the network addresses, the u-boot environment variables? (which might be set either by the user or some kind of board specific code).
Also U-Boot and Linux DTs have to be in sync all the time, if we disable one port in U-Boot but not in Linux we would mix up MAC addresses.
I see. But that shouldn't happen with the code above. But are you sure that this
uclass_get(UCLASS_ETH, &uc);uclass_foreach_dev(dev, uc) {
will work then? in my config (just enetc-0) there is only one eth device
# dm tree [snip] pci 2 [ + ] pci_generic_ecam |-- pcie@1f0000000 eth 0 [ + ] enetc_eth | |-- enetc-0 mdio 0 [ + ] enetc_mdio | |-- emdio-3 pci_generi 0 [ ] pci_generic_drv | |-- pci_4:0.4 dsa 0 [ ] felix-switch | |-- felix-switch pci_generi 1 [ ] pci_generic_drv | `-- pci_4:1f.0 [snip]
So as far as using generic fix-up code I'm all for it, but in this case we would need some platform specific rules to match Linux DT nodes to U-Boot eth addresses.
As for the write_hwaddr callback instead of enetc_set_primary_mac_addr, that is valid but I suppose it is outside the scope of this patch. That function is related to the runtime MAC address and not to the MAC passed to Linux.
according to the comment in eth-uclass.c this is not for (u-boot) runtime:
/* * Devices need to write the hwaddr even if not started so that Linux * will have access to the hwaddr that u-boot stored for the device. * This is accomplished by attempting to probe each device and calling * their write_hwaddr() operation. */
and the runtime mac address for u-boot is already set enetc_start().
-michael
This is fine, I'll move the IERB code to write_hwaddr.
This will also only be called if the device is not disabled in u-boot, from what I see. So it might be better to "fix" this.
I bet you are not the first/only one which needs this kind of "how do we propagate the hardware address to linux" where the devices might be unused in u-boot. There must be a better way to do this ;)
-michael