Hi Sean, thanks for getting back to me.
On 6/11/23 Sean Anderson wrote:
On 6/11/23 23:25, David Antliff wrote:
On 11/23/22 Sean Anderson wrote:
On 11/22/22 20:23, David Antliff wrote:
[snip]
So I took up your suggestion, enabled CONFIG_NVMEM & CONFIG_I2C_EEPROM, and with some trial and error I have got as far as added the following to my device tree:
axi { i2c@ff030000 { i2c-mux@74 { i2c@0 { eeprom@54 { mac_address: mac-address@23 { reg = <0x23 6>; }; }; }; }; };
ethernet@ff0e0000 { nvmem-cells = <&mac_address>; nvmem-cell-names = "mac-address"; }; };
(This is part of a user .dtsi so it's added by Yocto to the existing DT provided by the vendor's board definition).
The tree builds OK and I can view the correct nodes from U-Boot / fdt command.
From a little debugging, I see that the call in eth-uclass.c around line 515 returns a null pointer:
p = dev_read_u8_array_ptr(dev, "mac-address", ARP_HLEN);
This is expected. If (local-)mac-address is defined then nvmem_cell_get_by_name/nvmem_cell_read will not be used.
Yeah, so, I think I shot myself in the foot when writing this email, because although I am using the U-Boot device tree for my efforts (the one appended to the U-Boot binary, a la CONFIG_OF_SEPARATE), I actually used the Linux one in my email, which was a mistake because the "local-mac-address" has been populated with a valid address by that point. I'm actually not sure where that address comes from, because in the U-Boot device tree, I have:
local-mac-address = [ff ff ff ff ff ff];
So to be clear, I do not have a valid local-mac-address in the U-Boot device tree at the time U-Boot is looking for the MAC address.
And this results in U-Boot assigning the FF:FF:FF:FF:FF:FF address instead.
Yet, if I boot Linux, this device now appears in sysfs as /sys/bus/nvmem/devices/6-00544/nvmem, and I can read/write to it, so something is working. Linux ends up with the wrong MAC though (76:1b:db:1f:78:12, and I'm not sure where that comes from).
I think I have the right Ethernet device, as U-Boot reports:
ZYNQ GEM: ff0e0000, mdio bus ff0e0000, phyaddr 12, interface rgmii-id
Do you have any thoughts as to why U-Boot is not picking up the MAC address from the EEPROM, in this case, please?
The full sections of the relevant parts of the DT now look like this:
[snip]
ethernet@ff0e0000 { power-domains = <0x11 0x20>; iommus = <0x12 0x877>;
> #address-cells = <0x01>;
phy-mode = "rgmii-id"; nvmem-cells = <0x15>; clock-names = "pclk\0hclk\0tx_clk\0rx_clk\0tsu_clk"; local-mac-address = [76 1b db 1f 78 12];
This will prevent the nvmem-cells from being used. Is this your U-Boot device tree? Or is it from /sys/firmware?
Yes, this is from /sys/firmware - my mistake, as mentioned above. The U-Boot device tree looks like this:
ZynqMP> fdt print /axi/ethernet@ff0e0000 ethernet@ff0e0000 { compatible = "xlnx,zynqmp-gem", "cdns,gem"; status = "okay"; interrupt-parent = <0x00000005>; interrupts = <0x00000000 0x0000003f 0x00000004 0x00000000 0x0000003f 0x00000004>; reg = <0x00000000 0xff0e0000 0x00000000 0x00001000>; clock-names = "pclk", "hclk", "tx_clk", "rx_clk", "tsu_clk"; #address-cells = <0x00000001>; #size-cells = <0x00000000>; iommus = <0x00000012 0x00000877>; power-domains = <0x00000011 0x00000020>; resets = <0x00000013 0x00000020>; reset-names = "gem3_rst"; clocks = <0x00000004 0x0000001f 0x00000004 0x0000006b 0x00000004 0x00000030 0x00000004 0x00000034 0x00000004 0x0000002c>; phy-handle = <0x00000014>; phy-mode = "rgmii-id"; xlnx,ptp-enet-clock = <0x00000000>; local-mac-address = [ff ff ff ff ff ff]; nvmem-cells = <0x00000015>; nvmem-cell-names = "mac-address"; phandle = <0x00000067>; mdio { #address-cells = <0x00000001>; #size-cells = <0x00000000>; phandle = <0x00000068>; ethernet-phy@c { #phy-cells = <0x00000001>; compatible = "ethernet-phy-id2000.a231"; reg = <0x0000000c>; ti,rx-internal-delay = <0x00000008>; ti,tx-internal-delay = <0x0000000a>; ti,fifo-depth = <0x00000001>; ti,dp83867-rxctrl-strap-quirk; reset-gpios = <0x00000016 0x00000006 0x00000001>; phandle = <0x00000014>; }; }; };
I've noticed in some online examples that there's a compatible = "nvmem-cells" at the EEPROM level, so I tried:
ZynqMP> fdt print /axi/i2c@ff030000/i2c-mux@74/i2c@0 i2c@0 { #address-cells = <0x00000001>; #size-cells = <0x00000000>; reg = <0x00000000>; phandle = <0x0000006d>; eeprom@54 { compatible = "atmel,24c128", "nvmem-cells"; reg = <0x00000054>; phandle = <0x00000036>; mac-address@23 { reg = <0x00000023 0x00000006>; phandle = <0x00000015>; }; }; };
However this does not work either. Is this compatibility declaration required?
[snip]
You can also #define DEBUG in drivers/misc/nvmem.c
Thank you, I will try that.
-- David.