Messages in this thread | | | Subject | Re: [PATCH net-next v2 2/3] dt-bindings: dp83td510: Add binding for DP83TD510 Ethernet PHY | From | Dan Murphy <> | Date | Tue, 20 Oct 2020 14:14:17 -0500 |
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Andrew
On 10/20/20 2:07 PM, Andrew Lunn wrote: >> Humm. Are 1v and 2.4v advertised so it can be auto negotiated? Maybe a >> PHY tunable is not correct? Is this voltage selection actually more >> like pause and EEE? > [Goes and looks at the datasheet] > > Register 0x20E, bit 13: > > 1 = Advertise that the 10BASE-T1L PHY has increased transmit/ > receive level ability > 0 = Do not advertise that the 10BASE-T1L PHY has increased > transmit/receive level ability (default) > > So does this mean 2.4v?
This can also be strapped to a certain voltage level. The device may not have the regulators on board to drive a 2.4v signal. 1v signal AVDD is 1.8v and 2.4v the AVDD needs to be at least 3.3v
This Strap defines the voltage level requested by PHY during auto negotiation. It is reflected in bit 12 of 0x20E. While using Force mode for Linkup, the strap controls the output voltage and reflects in bit 12 of 0x18F6
Bit 12
1 = Enable 2.4 Vpp operating mode 0 = Enable 1.0 Vpp operating mode
So maybe this is a hybrid of tunable for master/slave and a DT for voltage level since the ability of the board to drive the signal can vary.
Dan
> Andrew
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