Hello I own an USB dongle which is a "Davicom DM96xx USB 10/100 Ethernet". According to the CHIP_ID, it is a DM9620. Since I needed for bringing network to uboot for a board, I have started to create its uboot's driver. My uboot driver is based on the dm9600 Linux driver. The dongle was working but very very slowy (24Kib/s). After some debug i found that the main problem was that it always link to 10Mbit/s Half-duplex. (according to the MAC registers) For checking the status of the dongle I have plugged it on a Linux box which give me: dm9601 6-2:1.0 enp0s29f0u2: link up, 100Mbps, full-duplex, lpa 0xFFFF But in fact the Linux driver is tricked. I have added debug of MDIO write/read and got: [157550.926974] dm9601 6-2:1.0 (unnamed net_device) (uninitialized): dm9601_mdio_write() phy_id=0x00, loc=0x00, val=0x8000 [157550.931962] dm9601 6-2:1.0 (unnamed net_device) (uninitialized): dm9601_mdio_write() phy_id=0x00, loc=0x04, val=0x05e1 [157550.951967] dm9601 6-2:1.0 (unnamed net_device) (uninitialized): dm9601_mdio_read() phy_id=0x00, loc=0x00, returns=0xffff [157550.951971] dm9601 6-2:1.0 (unnamed net_device) (uninitialized): dm9601_mdio_write() phy_id=0x00, loc=0x00, val=0xffff [157567.781989] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.796985] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.811989] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157567.826974] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff [157567.841972] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x00, returns=0xffff [157567.856974] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.871990] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157567.886974] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff [157567.906010] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.920986] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.935975] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157567.950974] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff [157567.965974] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x00, returns=0xffff [157567.980970] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157567.995973] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157568.010971] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff [157568.025973] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157568.040969] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157568.055971] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157568.070970] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff [157568.085971] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x00, returns=0xffff [157568.100971] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x01, returns=0xffff [157568.115973] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x04, returns=0xffff [157568.130970] dm9601 6-2:1.0 enp0s29f0u2: dm9601_mdio_read() phy_id=0x00, loc=0x05, returns=0xffff So the problem is the same than in my uboot driver, the PHY always return 0xFFFF. I have tried lots of hack but fail to bring the PHY up. So it exsists two problem: - Linux saying 100Mbps, full-duplex even if it is false. - the PHY which seems in bad state. For further information, the PHY is the internal one. On the dongle, only the davicom chip is present (along with some resistors/capacitors and a quartz), so I think of the absence of an external PHY. Regards
