Slow link up times with Gigabit Ethernet on the STM32MP1

[Grodriguez]

I am testing Ethernet on the STM32MP1 (on both the EV1 and DK2 eval boards) and seeing slow link up times when the board is connected to a Gigabit Ethernet switch. Here's an excerpt from the dmesg traces showing link up times of 6-7 seconds:

[    8.931934] Generic PHY stmmac-0:00: attached PHY driver [Generic PHY] (mii_bus:phy_addr=stmmac-0:00, irq=POLL)
[    8.952777] dwmac4: Master AXI performs any burst length
[    8.956664] stm32-dwmac 5800a000.ethernet eth0: No Safety Features support found
[    8.964160] stm32-dwmac 5800a000.ethernet eth0: IEEE 1588-2008 Advanced Timestamp supported
[    8.972895] stm32-dwmac 5800a000.ethernet eth0: registered PTP clock
[   14.169871] stm32-dwmac 5800a000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx

Since my application does not really need Gigabit Ethernet, I tried limiting the speed to 100 Mbps in the device tree, as described here: https://wiki.st.com/stm32mpu/wiki/Ethernet_device_tree_configuration

However the results are still similar; typical link up times are in the ~6 second range.

Is there any way to shorten the link up times?

BR,

Guillermo

[Olivier GALLIEN]

Hi @Grodriguez​ 

did you try to use static address to remove DHCP request ?

Olivier

[Grodriguez]

Hi Olivier,

Yes, I tested with static address, anyway note that the issue is related to the link time (Ethernet level), not to the IP configuration.

Guillermo

[Macdog]

I am also testing the stm32mp157c-dk2 eval board with a buildroot generated, and am also seeing the exact same Ethernet link-up delay, also in the ~6 second range. Is there any way to improve the link-up timing?

[Macdog]

Sorry I am new to the forum, didn't mean to attach the log, wanted to display:

Starting network: [  3.327679] stm32-dwmac 5800a000.ethernet eth0: PHY [stmmac-0:00] driver [RTL8211F Gigabit Ethernet]

[  3.368439] dwmac4: Master AXI performs any burst length

[  3.375121] stm32-dwmac 5800a000.ethernet eth0: No Safety Features support found

[  3.386583] stm32-dwmac 5800a000.ethernet eth0: IEEE 1588-2008 Advanced Timestamp supported

[  3.399417] stm32-dwmac 5800a000.ethernet eth0: registered PTP clock

[  3.409993] stm32-dwmac 5800a000.ethernet eth0: configuring for phy/rgmii-id link mode

[  9.067672] stm32-dwmac 5800a000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx

[  9.080502] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready