aleksandriusz

I fixed this by manually generating my own rk3568-odroid-m1.dts file and changing tx_delay to 0x35. I'm not sure why this fix isn't yet available by default. Here we go: rk3568-odroid-m1.dtb Replace the file in `/boot/dtb/rockchip/rk3568-odroid-m1.dtb` and reboot. Enjoy your 1000 Mbps link. root@odroidm1 /b/d/rockchip# uname -a Linux odroidm1 7.1.9-edge-rockchip64 #1 SMP PREEMPT Wed Aug 19 16:20:32 UTC 2026 aarch64 GNU/Linux root@odroidm1 /b/d/rockchip# iperf3 -c 192.168.0.148 Connecting to host 192.168.0.148, port 5201 [ 5] local 192.168.0.204 port 37010 connected to 192.168.0.148 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 114 MBytes 952 Mbits/sec 0 437 KBytes [ 5] 1.00-2.00 sec 113 MBytes 946 Mbits/sec 0 486 KBytes [ 5] 2.00-3.00 sec 112 MBytes 936 Mbits/sec 0 486 KBytes [ 5] 3.00-4.00 sec 112 MBytes 945 Mbits/sec 0 486 KBytes [ 5] 4.00-5.00 sec 112 MBytes 940 Mbits/sec 0 513 KBytes [ 5] 5.00-6.00 sec 112 MBytes 943 Mbits/sec 0 537 KBytes [ 5] 6.00-7.00 sec 112 MBytes 944 Mbits/sec 0 537 KBytes [ 5] 7.00-8.00 sec 112 MBytes 937 Mbits/sec 0 537 KBytes [ 5] 8.00-9.00 sec 113 MBytes 948 Mbits/sec 0 537 KBytes [ 5] 9.00-10.00 sec 113 MBytes 945 Mbits/sec 0 704 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 1.10 GBytes 944 Mbits/sec 0 sender [ 5] 0.00-10.01 sec 1.10 GBytes 941 Mbits/sec receiver

Can't confirm, still many packet losses in the newest U-Boot/Linux edge: # grep -a --null-data U-Boot /dev/mtd0ro U-Boot SPL 2026.07_armbian-2026.07-Sece3-Pb90d-H1a0d-Veca7-B5da4-R448a (Aug 14 2026 - 13:26:37 +0000) ^ also tested on mmcblk1 and nvme0n1 # uname -a Linux odroidm1 7.1.8-edge-rockchip64 #2 SMP PREEMPT Sun Aug 9 18:26:58 UTC 2026 aarch64 GNU/Linux root@odroidm1 ~# iperf3 -c 192.168.0.116 Connecting to host 192.168.0.116, port 5201 [ 5] local 192.168.0.204 port 47826 connected to 192.168.0.116 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 28.4 MBytes 238 Mbits/sec 469 18.4 KBytes [ 5] 1.00-2.00 sec 22.2 MBytes 187 Mbits/sec 335 14.1 KBytes [ 5] 2.00-3.00 sec 17.8 MBytes 149 Mbits/sec 284 18.4 KBytes [ 5] 3.00-4.00 sec 21.4 MBytes 179 Mbits/sec 367 1.41 KBytes [ 5] 4.00-5.00 sec 21.9 MBytes 183 Mbits/sec 364 14.1 KBytes [ 5] 5.00-6.00 sec 26.8 MBytes 224 Mbits/sec 469 18.4 KBytes [ 5] 6.00-7.00 sec 26.9 MBytes 225 Mbits/sec 385 15.6 KBytes [ 5] 7.00-8.00 sec 28.2 MBytes 237 Mbits/sec 506 25.5 KBytes [ 5] 8.00-9.00 sec 28.6 MBytes 240 Mbits/sec 503 15.6 KBytes [ 5] 9.00-10.00 sec 25.4 MBytes 212 Mbits/sec 417 5.66 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 248 MBytes 208 Mbits/sec 4099 sender [ 5] 0.00-10.01 sec 247 MBytes 207 Mbits/sec receiver

Can't confirm, still the same thing. U-boot built 7 days ago (linux-u-boot-odroidm1-edge/sid,now 26.8.0-trunk.105 arm64) # uname -r 7.0.11-edge-rockchip64 # grep -a --null-data U-Boot /dev/mtd0ro U-Boot SPL 2026.01_armbian-2026.01-S127a-Pb401-H8652-Vab81-Bd0d2-R448a (May 31 2026 - 05:41:25 +0000) # grep -a --null-data U-Boot /dev/mmcblk1 U-Boot SPL 2026.01_armbian-2026.01-S127a-Pb401-H8652-Vab81-Bd0d2-R448a (May 31 2026 - 05:41:25 +0000) 100 Mbps link still performs much better by some unknown reason. Hmm. (I've already tested the cable, any other computer/laptop transmits the data just fine at full Gigabit speed)

No difference on an installation with `linux-u-boot-odroidm1-edge/sid,now 26.8.0-trunk.12` and `linux-image-edge-rockchip64/sid` (7.0.8-edge-rockchip64 ), 1000 Mbps link is still heavily degraded, especially on packets leaving my gateway router. Could anyone subscribed to this thread confirm that's still the case? Thanks! 1000 Mbps link: root@odroidm1 ~# ethtool -s eth0 speed 1000 duplex full autoneg on root@odroidm1 ~ [1]# iperf3 -c 10.0.3.3 Connecting to host 10.0.3.3, port 5201 [ 5] local 10.0.3.2 port 51448 connected to 10.0.3.3 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 1.00 MBytes 8.38 Mbits/sec 12 22.8 KBytes [ 5] 1.00-2.00 sec 384 KBytes 3.15 Mbits/sec 2 11.4 KBytes [ 5] 2.00-3.00 sec 0.00 Bytes 0.00 bits/sec 1 10.4 KBytes [ 5] 3.00-4.00 sec 256 KBytes 2.10 Mbits/sec 0 19.9 KBytes 100 Mbps link: root@odroidm1 ~# ethtool -s eth0 speed 100 duplex full autoneg off root@odroidm1 ~# iperf3 -c 10.0.3.3 Connecting to host 10.0.3.3, port 5201 [ 5] local 10.0.3.2 port 38436 connected to 10.0.3.3 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 6.00 MBytes 50.3 Mbits/sec 0 2.38 MBytes [ 5] 1.00-2.00 sec 8.38 MBytes 70.3 Mbits/sec 0 7.87 MBytes [ 5] 2.00-3.00 sec 9.25 MBytes 77.6 Mbits/sec 0 7.87 MBytes # grep -a --null-data U-Boot /dev/mtd0ro U-Boot SPL 2026.01_armbian-2026.01-S127a-P2477-H8652-Vab81-Bd0d2-R448a (May 15 2026 - 06:45:08 +0000)

Just a quick update for those who are following this thread, looks like there was a pull request for U-Boot with this fix (2026-02-02): https://github.com/armbian/build/pull/9333 Waiting for the U-Boot update i guess (i'm using `linux-u-boot-odroidm1-edge/sid` currently).

Hi, looks like the issue still persists, but I have a temporary solution in case if your upload speed drops *way* beyond yours (2 Mbps for me). You can force-use a 100 Mbps link speed. `iperf3` results below. Literally 50x speed increase in my case! I've performed these benchmarks connecting to my VPS via wireguard: ``` $ cat /dev/mtd/by-name/U-Boot | strings | grep -B1 "u-boot,version"` U-Boot: 2026.01_armbian-2026.01-S127a-Pc2e6-H706e-Vab81-B2eb2-R448a ``` Linux 6.18.10-current-rockchip64 Standard operation (1000 Mbps): ```root@odroidm1 ~# ethtool -s eth0 speed 1000 duplex full root@odroidm1 ~# iperf3 -c 10.0.3.1 Connecting to host 10.0.3.1, port 5201 [ 5] local 10.0.3.2 port 42538 connected to 10.0.3.1 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 384 KBytes 3.14 Mbits/sec 5 14.7 KBytes [ 5] 1.00-2.00 sec 384 KBytes 3.15 Mbits/sec 5 6.68 KBytes [ 5] 2.00-3.00 sec 384 KBytes 3.14 Mbits/sec 2 13.4 KBytes [ 5] 3.00-4.00 sec 256 KBytes 2.10 Mbits/sec 6 9.35 KBytes [ 5] 4.00-4.43 sec 128 KBytes 2.42 Mbits/sec 0 22.7 KBytes ``` Dirty fix, link capped at 100 Mbps at most: ``` root@odroidm1 ~# ethtool -s eth0 speed 100 duplex full root@odroidm1 ~# iperf3 -c 10.0.3.1 Connecting to host 10.0.3.1, port 5201 [ 5] local 10.0.3.2 port 42354 connected to 10.0.3.1 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 11.4 MBytes 95.3 Mbits/sec 0 1.03 MBytes [ 5] 1.00-2.00 sec 10.5 MBytes 88.1 Mbits/sec 0 1.03 MBytes [ 5] 2.00-3.00 sec 11.4 MBytes 95.4 Mbits/sec 0 1.10 MBytes [ 5] 3.00-4.00 sec 10.2 MBytes 86.0 Mbits/sec 0 1.10 MBytes [ 5] 4.00-4.48 sec 5.00 MBytes 87.4 Mbits/sec 0 1.10 MBytes ``` So.. yeah. While using Wireshark I also saw *a lot* of TCP retransmissions too, which usually don't happen that at 100 Mbps link in my configuration.