On 11/23/22 Sean Anderson wrote:
> On 11/22/22 20:23, David Antliff wrote:
> >
> > I'm looking to extract the board's MAC address from serial I2C EEPROM at
>boot time, so
> > I'm trying to work out how I can tell if U-Boot is actually able to
>communicate with this
> > EEPROM, outside of manual i2c commands.
> >
> > I have set CONFIG_ZYNQ_MAC_IN_EEPROM and CONFIG_ZYNQ_MAC_IN_EEPROM
> > however I'm not completely sure that this is working with UltraScale+ Zynq
>MPSoC
> > boards - I'm using a ZCU208. There's no log message on the U-Boot console
>to say
> > that there was an attempt to read the MAC address, and with ethaddr unset,
>this
> > variable is set by U-Boot to the value taken from the device tree rather
>than EEPROM:
> >
> > ethernet@ff0e0000 {
> > ...
> > local-mac-address = [00 0a 35 00 22 01];
> > ...
> >
> > I would expect it to be 00 0a 35 07 60 1c based on the contents of the
>EEPROM.
> >
> > I would like to understand how to debug this. I read that the command
>"eeprom" has been
> > deprecated for some time (I don't have it enabled), with some I2C serial
>EEPROM devices
> > now supported by the "Driver Model" - aka DM.
> >
> > Thus I did find:
> >
> >> dm uclass
> > ...
> > uclass 39: i2c_eeprom
> > 0 eeprom@54 @ 7dd21420
> > ...
> >
> > And I'm able to communicate with the device via commands like:
> >
> > ZynqMP> i2c md 54 0.2 40 200000
> > 0000: 5a 43 55 32 30 38 ff ff ff ff ff ff ff ff ff ff ZCU208..........
> > 0010: ff 41 30 32 38 33 32 32 30 34 31 34 33 33 32 38 .A02832204143328
> > 0020: 31 2e 33 00 0a 35 07 60 1c 00 0a 35 07 60 1d 00 1.3..5.`...5.`..
> > 0030: 0a 35 07 60 1e 00 0a 35 07 60 1f 41 08 ff ff ff .5.`...5.`.A....
> >
> > The MAC address is 6 bytes starting at offset 0x23 (00 0a 35 07 60 1c).
[snip]
> > The EEPROM device in question is an M24128.
> >
> > CONFIG_SYS_I2C_EEPROM_ADDR=0x54
> > CONFIG_SYS_I2C_EEPROM_BUS=6
> > CONFIG_SYS_EEPROM_SIZE=16384
> > CONFIG_SYS_I2C_EEPROM_ADDR_LEN=2
> > CONFIG_ZYNQ_GEM_I2C_MAC_OFFSET=0x23
> > CONFIG_ZYNQ_MAC_IN_EEPROM=y
> >
> > U-Boot 2021.01 (Xilinx fork: git://github.com/Xilinx/u-boot-xlnx.git)
[snip]
> This doesn't directly address your question, but have you tried using
>nvmem-cells?
>
> You enable CONFIG_NVMEM and CONFIG_I2C_EEPROM, and modify your device tree
>like
>
> i2c {
> eeprom@54 {
> #address-cells = <1>;
> #size-cells = <1>;
> compatible = "atmel,24c08";
> reg = <0x54>;
>
> mac_address: mac-address@23 {
> reg = <0x23 6>;
> };
> };
> };
>
> ethernet {
> nvmem-cells = <&mac_address>;
> nvmem-cell-names = "mac-address";
> };
>
> You'll need 2022.07 for this I think. This is the same method which
> Linux uses. I added this specificly to be able to load MAC addresses
> from EEPROMs without needing to hard code stuff into Kconfig.
Hi Sean,
Apologies for bringing this thread back to life more than 6 months later, but
I'm not
quite getting this to work.
I have finally had the opportunity to upgrade to U-Boot 2023.1, and the first
thing I
noticed was that the old way of retrieving the MAC address from the EEPROM
fails,
as is expected as I understand that support was removed sometime after 2021.
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);
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:
axi {
/* .... */
i2c@ff030000 {
power-domains = <0x11 0x26>;
pinctrl-names = "default\0gpio";
#address-cells = <0x01>;
pinctrl-0 = <0x1a>;
interrupts = <0x00 0x12 0x04>;
clocks = <0x04 0x3e>;
#size-cells = <0x00>;
interrupt-parent = <0x05>;
clock-frequency = <0x61a80>;
compatible = "cdns,i2c-r1p14";
pinctrl-1 = <0x1b>;
status = "okay";
reg = <0x00 0xff030000 0x00 0x1000>;
phandle = <0x6c>;
scl-gpios = <0x19 0x10 0x00>;
sda-gpios = <0x19 0x11 0x00>;
i2c-mux@74 {
#address-cells = <0x01>;
i2c-mux-idle-disconnect;
#size-cells = <0x00>;
compatible = "nxp,pca9548";
reg = <0x74>;
i2c@0 {
#address-cells = <0x01>;
#size-cells = <0x00>;
reg = <0x00>;
phandle = <0x6d>;
eeprom@54 {
compatible = "atmel,24c128";
reg = <0x54>;
phandle = <0x36>;
mac-address@23 {
reg = <0x23 0x06>;
phandle = <0x15>;
};
};
};
/* ... */
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];
resets = <0x13 0x20>;
interrupts = <0x00 0x3f 0x04 0x00 0x3f 0x04>;
clocks = <0x04 0x1f 0x04 0x6b 0x04 0x30 0x04 0x34 0x04 0x2c>;
#size-cells = <0x00>;
interrupt-parent = <0x05>;
compatible = "xlnx,zynqmp-gem\0cdns,gem";
status = "okay";
nvmem-cell-names = "mac-address";
reg = <0x00 0xff0e0000 0x00 0x1000>;
phandle = <0x67>;
phy-handle = <0x14>;
reset-names = "gem3_rst";
xlnx,ptp-enet-clock = <0x00>;
mdio {
#address-cells = <0x01>;
#size-cells = <0x00>;
phandle = <0x68>;
ethernet-phy@c {
ti,dp83867-rxctrl-strap-quirk;
ti,tx-internal-delay = <0x0a>;
#phy-cells = <0x01>;
reset-gpios = <0x16 0x06 0x01>;
compatible = "ethernet-phy-id2000.a231";
ti,fifo-depth = <0x01>;
ti,rx-internal-delay = <0x08>;
reg = <0x0c>;
phandle = <0x14>;
};
};
};
The full tree is here: https://pastebin.com/WQKBxK7x
I feel like I'm close, but must be missing something.
-- David.
