Messages in this thread | | | Date | Thu, 31 Oct 2019 18:14:16 +0100 | From | Michael Walle <> | Subject | Re: [RFC PATCH 2/3] dt-bindings: net: phy: Add support for AT803X |
| |
Am 2019-10-31 17:45, schrieb Florian Fainelli: > On 10/30/19 5:14 PM, Michael Walle wrote: >>> So we can later add atheros,rgmii-io-2v5. That might need a regulator >>> as well. Maybe add that 2.5V is currently not supported. >> >> There is no special setting for the 2.5V mode. This is how it works: >> there is one voltage pad for the RGMII interface. Either you connect >> this pad to a 2.5V voltage or you leave it open (well you would >> connect some decoupling Cs). If you leave it open the internal LDO, >> which seems to be enabled in any case takes over, supplying 1.5V. then >> there is a bit in the debug register which can switch the internal LDO >> to 1.8V. So if you'll use 2.5V the bit is irrelevant. >> >> Like I said maybe a "rgmii-io-microvolts" is a better property and >> only in the 1800000 setting would turn on this bit. but then both >> other setting would be a noop. > > That would align with the regulator subsystem units, but maybe you > should have the PHY driver be a regulator provider for itself so you > can > chose wether you want to operate at 1.5V or 1.8V, or you have an > external regulator providing I/O supplies. That would make the whole > thing consistent from the driver's perspective and would not > necessarily > be too far fetched from a HW description perspective?
Sounds good. But again, I'm not too familiar with that. Could you give an example how the device tree would look like then? Maybe that way I can work myself through that regulator stuff.
-- michael
| |