What is the output of ethtool on Rock Pi 4?

ROCK 4 Series
1

According to RK3399 datasheet

Automatic generation of PAUSE frame control or backpressure signal to the GMAC core based on Receive FIFO-fill (threshold configurable) level

I don’t know whether this means full-duplex ethernet flow control.
Ethtool should tell you whether ethernet adapter on rock pi 4 is capable of full-duplex flow control.
What is the output of ethtool on Rock Pi 4?

2

Yes, it is capable of full-duplex.

Most of the nowadays hardware is full-duplex because it is easy to product as such.

3

I meant full-duplex ethernet flow control. Not full-duplex gigabit connection.

What is the output of ethtool on your rock pi 4?

4 
$ ethtool eth0
Settings for eth0:
	Supported ports: [ TP MII ]
	Supported link modes:   10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Supported pause frame use: Symmetric Receive-only
	Supports auto-negotiation: Yes
	Supported FEC modes: Not reported
	Advertised link modes:  10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Advertised pause frame use: Symmetric Receive-only
	Advertised auto-negotiation: Yes
	Advertised FEC modes: Not reported
	Speed: Unknown!
	Duplex: Unknown! (255)
	Port: MII
	PHYAD: 0
	Transceiver: internal
	Auto-negotiation: on
	Supports Wake-on: ug
	Wake-on: d
	Current message level: 0x0000003f (63)
			       drv probe link timer ifdown ifup
	Link detected: no
5 
Settings for eth0:
        Supported ports: [ TP AUI BNC MII FIBRE ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                             100baseT/Half 100baseT/Full
                                             1000baseT/Half 1000baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: Yes
        Link partner advertised FEC modes: Not reported
        Speed: 1000Mb/s
        Duplex: Full
        Port: MII
        PHYAD: 0
        Transceiver: external
        Auto-negotiation: on
        Supports Wake-on: ug
        Wake-on: d
        Current message level: 0x0000003f (63)
                               drv probe link timer ifdown ifup
        Link detected: yes