I have no eMMC and the card isn't UHS-II (I use WD Purple cards, they are UHS-I). I don't think I have any UHS-II cards at the moment... Could try a different one though.

@rm_ On my RV2, there's no such load. Mine waits at the GDM3 login screen (Wayland), it's booted via NVME, no Wifi nor BT configured, and I have a shell via Ethernet. I see a difference in IPI4 dubbed "IRQ work interrupts" which may cause this but I have no clue about the real root cause. There's a patch with comments on that: https://patchew.org/linux/25833c44051f02ea2fd95309652628e2b1607a1e.camel@lenze.com/ , however I have not investigated which of the patches / corrections are in the actual 6.18.26-current-spacemit. I have 53/57° C temp with cat $(find /sys -name temp), I presume yours is higher... interrupts

@humanus Thanks, just noticed the log. Interestingly looks like it's the mmc part. A few things I can think of: 1. emmc is only presented on A7A/S, so if you are using emmc or your board has an emmc, it might be a problem. You can try to disable sdc2 on device tree and see if it works. 1. sd card part is the same on A7A/S/Z, but I don't think my card is a UHS-II card. Looking at the log, it might be doing something with UHS-II, so it might be worth trying a different SD card to see if it behaves differently. If it does turn out to be related to UHS-II handling, I can look into a proper fix later. on.

ok my findings root@rk3318-box:/boot# cat *Env.txt verbosity=1 bootlogo=true console=both overlay_prefix=rockchip fdtfile=rockchip/rk3318-box.dtb rootdev=UUID=a3e848f3-8d54-412d-9184-5bc40ab76686 rootfstype=ext4 overlays=hdmi-audio rk3318-box-cpu-hs rk3318-box-led-conf1 rk3318-box-wlan-ap6334 usbstoragequirks=0x2537:0x1066:u,0x2537:0x1068:u root@rk3318-box:/boot# sudo ln -s /usr/lib/firmware/brcm/brcmfmac4334-sdio.bin /usr/lib/firmware/brcm/brcmfmac4334-sdio.rockchip,rk3318-box.bin ### it was missing according the log sudo rm /usr/lib/firmware/brcm/brcmfmac4334-sdio.rockchip,rk3318-box.txt ### this one did not do the job , you could ofcourse backup ... sudo wget -O /usr/lib/firmware/brcm/brcmfmac4334-sdio.rockchip,rk3318-box.txt https://pastebin.com/raw/00gLSkKS ### the nvram hosted in this topic after the reboot the wifi worked fine for me

@alexc @qq20739111 I would be very surprised if the UART log showed anything other than mine. You can find it attached above.