jorgesilva Posted March 12, 2021 Share Posted March 12, 2021 Hi - I'm running on a Rockpi 4c on Armbian 21.02.3 Buster and it the pcie-gen2 overlay doesn't seem to do anything - I have edited the /boot/armbianEnv.txt user_overlays=rockpi-penta overlays=pcie-gen2 It makes no difference if I include the pci-gen2 overlay. lspci -vv LnkCap: Port #0, Speed 8GT/s, Width x2, ASPM not supported, Exit Latency L0s <256ns, L1 <8us ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+ LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk- ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- LnkSta: Speed 5GT/s, Width x2, TrErr- Train- SlotClk- DLActive- BWMgmt- ABWMgmt and I always get this message in dmesg : 8.000 Gb/s available PCIe bandwidth, limited by 5.0 GT/s PCIe x2 link at 0000:00:00.0 (capable of 15.752 Gb/s with 8.0 GT/s PCIe x2 link) I am running a raid5 array and at most I seem to get just shy of at most 100MBs, - I get the same number on individual disks. I 0 Quote Link to comment Share on other sites More sharing options...
Werner Posted March 12, 2021 Share Posted March 12, 2021 Providing logs with armbianmonitor -u helps with troubleshooting and significantly raises chances that issue gets addressed. 0 Quote Link to comment Share on other sites More sharing options...
piter75 Posted March 13, 2021 Share Posted March 13, 2021 19 hours ago, jorgesilva said: It makes no difference if I include the pci-gen2 overlay. True, it makes no difference because the unsupported by Rockchip Gen 2 link speed was mainlined into ROCK Pi 4(a/b/c) device trees so you don't need the overlay ;-) https://github.com/torvalds/linux/blob/master/arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi#L472 I am not sure it should be mainlined this way but it's another story. 19 hours ago, jorgesilva said: 8.000 Gb/s available PCIe bandwidth, limited by 5.0 GT/s PCIe x2 It confirms that you are indeed running at Gen2 speeds and have 1GiB/s physical bandwidth. 0 Quote Link to comment Share on other sites More sharing options...
jorgesilva Posted March 13, 2021 Author Share Posted March 13, 2021 Thanks for the help, I guess my question is why is it defaulting to 5GT/s and not 8GT/s - root@mininas:~# armbianmonitor -u System diagnosis information will now be uploaded to Please post the URL in the forum where you've been asked for. No url - I have run it in the past and have had a url, what am I doing wrong? 0 Quote Link to comment Share on other sites More sharing options...
piter75 Posted March 13, 2021 Share Posted March 13, 2021 1 hour ago, jorgesilva said: Thanks for the help, I guess my question is why is it defaulting to 5GT/s and not 8GT/s RK3399 officially supports version 1.0 (2.5GT/s) and unofficially 2.0 (5GT/s). PCIE 3.0 support is needed for 8GT/s. https://en.wikipedia.org/wiki/PCI_Express#History_and_revisions 0 Quote Link to comment Share on other sites More sharing options...
jorgesilva Posted March 13, 2021 Author Share Posted March 13, 2021 Hi - so everything is ok and the dmesg message is more an FYI and not a misconfiguration i.e. it should be running at running at 8GTs. - if so thank you very much for your help. 8.000 Gb/s available PCIe bandwidth, limited by 5.0 GT/s PCIe x2 link at 0000:00:00.0 (capable of 15.752 Gb/s with 8.0 GT/s PCIe x2 link) 0 Quote Link to comment Share on other sites More sharing options...
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