[PATCH 4/5] ARM: novena: Read Ethernet MAC address from EEPROM
John Watts
contact at jookia.org
Wed Jan 25 05:31:04 PST 2023
On Wed, Jan 25, 2023 at 09:19:23AM +0100, Sascha Hauer wrote:
> Yes, normally it should be set up already, unless of course there is
> some needed pinctrl configuration in an unrelated device tree node.
>
> Sascha
Hi Sascha,
Here's what I think is going on:
- The I2C line requires 3v3_DELAYED for pull-ups
- The EEPROM requires 3v3_DELAYED for power
- 3v3_DELAYED requires VGEN5 from the PMIC (acts as a gate)
- The PMIC is loaded after the EEPROM
Most things on the board require these delayed rails, so I'm wondering
what the approach should be here. Should I:
- Rewrite the device tree to reference these delayed rails
- Probe the PMIC first
I did try this:
reg_3p3v: regulator-3p3v {
compatible = "regulator-fixed";
regulator-name = "3P3V_DELAYED";
regulator-min-microvolt = <3300000>;
regulator-max-microvolt = <3300000>;
regulator-always-on;
gate-supply = <®_vgen6>;
};
But Barebox doesn't seem to see the 'regulator-always-on' as
'start immediately'. I actually updated the eeprom node to use
reg_3p3v as vcc-supply and things were still probed in the wrong order.
John.
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