Update — Working fix available I've got eMMC detection working on my Radxa Zero 3W with Armbian Trixie (vendor kernel 6.1.115, SD card boot). The fix uses a device tree overlay to inject the missing voltage regulators, pinctrl references, and eMMC capabilities into the base DTB, combined with a small systemd service that rebinds the SDHCI driver to work around a deferred probe timing issue. After applying, the eMMC is detected as expected: mmc0: new HS200 MMC card at address 0001 mmcblk0: mmc0:0001 8GTF4R 7.28 GiB armbian-install works normally after that to migrate to eMMC boot. The rebind service is conditionally skipped when booting from eMMC so it doesn't interfere. I've attached a zip with all the files. The README.md inside has the full details — root cause analysis, what was tried and failed (including full DTB recompile), how the fix works, installation/verification/revert steps, and known limitations (the pinctrl phandle values are specific to this kernel build). I still working on a version that does not need the rebind service for sd cards. but for now you need the rebind on the sd card to get it to find the EMMC so you can install. emmc-fix.zip

Update — eMMC now detected (workaround found) After significant debugging, I have identified and worked around the issue. Here's what I found: What the shipped DTB is missing for the eMMC controller (/mmc@fe310000): vmmc-supply / vqmmc-supply — voltage regulator references pinctrl-0 / pinctrl-names — pin muxing for the 8-bit eMMC data bus, clock, command, and data strobe lines cap-mmc-highspeed, mmc-hs200-1_8v, no-sd, no-sdio — eMMC capability flags Interestingly, the PMU IO domains (syscon@fdc20000/io-domains) are already correctly configured with vccio2 = 1.8V, and the pinctrl groups (emmc-bus8, emmc-clk, emmc-cmd, emmc-datastrobe) exist under /pinctrl/emmc/. The board-level wiring is all there in the DTB — it's just not connected to the eMMC controller node. Root cause: The Armbian Trixie vendor kernel (6.1.115) ships only rk3566-radxa-zero3.dtb (generic Zero 3), not the 3W-specific rk3566-radxa-zero-3w.dtb that the upstream Linux kernel has. The upstream DTS includes all of the above for the 3W model. Additional finding — deferred probe timing issue: Even after patching all missing properties via a device tree overlay, the eMMC still doesn't appear on first boot. The SDHCI driver (sdhci-dwcmshc) probes before the overlay's regulators are registered, receives dummy regulators instead of deferring, and initializes the controller without real power. A manual unbind/rebind of the driver after boot causes immediate detection: mmc0: new HS200 MMC card at address 0001 mmcblk0: mmc0:0001 8GTF4R 7.28 GiB I have a working fix (overlay + early-boot driver rebind) that I testing before publishing. The proper long-term solution would be for Armbian to ship the rk3566-radxa-zero-3w.dtb from the upstream kernel, or merge its board-level eMMC configuration into the existing rk3566-radxa-zero3.dtb.

I also saw that both apt and beta repo's do not contain recent rockchip64 kernels at the moment. There is only a recent generic arm64 one. So it is not only my rock3a, also my nanopi-r6c would be affected, but I use own/other/vendor kernels as well, so specific 6.18.8 is not an issue for me. I use extlinux or grub to select a certain kernel (6.19 flavor on nanopi-r6c for example). For my rock3a, I need vendor kernel, but if you use mainline based, you could use standard Debian backports kernel: https://packages.debian.org/trixie-backports/linux-image-arm64 You need to get the .dtb manually and I just assume most features are supported when the rock3a has mainline U-Boot in SPI. You need of course add that to sources.list and specifically select it. You could also use Armbian build framwork to build a 6.18.x yourself, you will also get a header files package then. For Debian14 I see there is: /usr/lib/linux-image-6.18.15+deb14-arm64/rockchip/rk3568-rock-3a.dtb But as indicated, this is total DIY, I have not tested it. I only know that on rock5b I could run standard distro since quite some months, but use 6.1.115 vendor one as I need all RK3588 HW to work.

Ok, after doing more tests the issue was the boot switch on the board. It must be switched to boot from SD/eMMC and not SPI (BIOS). Then reboot works fine.

ha extension is not a part of the framework. Copy from here https://github.com/armbian/os/tree/main/userpatches/extensions