fedora-sbc

Worked examples of Fedora running on SBC hardware via an open firmware stack.

These are worked examples, not a maintained project. Corrections, additions, and reports from people working on the same or similar hardware are welcome — open an issue for specific problems or inaccuracies, or start a discussion for questions and experience sharing.

What These Examples Demonstrate

Each example documents a complete boot chain from power-on to a running Fedora userspace, built on the following architectural principles:

• Mainline U-Boot with EFI — open-source bootloader, no vendor binary blobs in the boot path beyond what the SoC architecture requires (OpenSBI on RISC-V, TF-A on AArch64)
• systemd-boot as the EFI boot manager — standard UEFI handoff between U-Boot and the OS, Boot Loader Specification (BLS) entries for kernel management
• Fedora packages as the default — standard Fedora package repositories and userspace wherever available; custom builds only where Fedora packaging gaps require them, with the gap explicitly identified

The goal in each case is a board that boots to a functional Fedora userspace and can receive kernel and package updates through normal Fedora tooling.

Scope

These examples cover the firmware and boot chain layer. The kernel strategy varies by architecture, driven by Fedora packaging availability:

AArch64 boards use the Fedora-packaged kernel installed via dnf where the board's DTB is included in the Fedora aarch64 kernel package. dracut generates an initramfs automatically via kernel-install, and dnf update kernel works without manual intervention. UUID references in boot entries are safe. Where the Fedora aarch64 kernel package does not yet include a board's DTB (e.g. Allwinner H618), a custom kernel build is required — the same packaging-gap pattern as riscv64.

RISC-V (riscv64) boards have no kernel RPM in standard Fedora repos — riscv64 builds exist on Fedora's Koji infrastructure but cannot be installed cleanly alongside a standard Fedora system without repo conflicts. A custom-built kernel is therefore required. To avoid needing an initrd for early driver loading, all drivers in the rootfs path are compiled in (=y). This is a workaround for a packaging gap, not a design preference — when Fedora ships riscv64 kernel RPMs in standard repos, these boards should migrate to the packaged kernel + dracut path.

The examples show where the goal was reached, where it was partially reached, and where it is blocked. A working result and an honest status report on an incomplete one are both useful outputs.

Boards

Board	SoC	Arch	Status	Boot Chain
Radxa Rock Pi 4 Plus	Rockchip RK3399	aarch64	✅ Fedora 43	boot-chain.md
Milk-V Mars	StarFive JH7110	riscv64	✅ Fedora 43	boot-chain.md
Orange Pi RV	StarFive JH7110	riscv64	✅ Fedora 43	boot-chain.md
ASUS Tinker Board 3	Rockchip RK3566	aarch64	⚠️ On hold — ethernet DMA	boot-chain.md
Raspberry Pi 3 Model B	Broadcom BCM2837	aarch64	✅ Fedora 43	boot-chain.md
Orange Pi Zero 3	Allwinner H618	aarch64	✅ Fedora 43	boot-chain.md

Boot Stage Summaries

Radxa Rock Pi 4 Plus (RK3399, aarch64) — ✅ Fedora 43

Stage	Detail
Boot ROM	RK3399 — raw offset, sector 64
SPL	idbloader (DDR init + SPL), SD card raw
Secure firmware	TF-A BL31 v2.12.0, embedded in U-Boot FIT
Bootloader	U-Boot v2026.01, SD card raw
Boot manager	systemd-boot (bootctl install — full BLS)
Kernel	Linux 6.19.9, Fedora-packaged
initrd	dracut (via kernel-install, automatic)
root=	UUID safe
Rootfs	eMMC, ext4
efivarfs	rw (EFI_RT_VOLATILE_STORE=y)

Milk-V Mars (StarFive JH7110, riscv64) — ✅ Fedora 43

Stage	Detail
Boot ROM	JH7110 — partition type GUID
SPL	U-Boot SPL v2026.01, SPI NOR
Secure firmware	OpenSBI v1.8.1, embedded in U-Boot FIT
Bootloader	U-Boot v2026.01, SPI NOR
Boot manager	systemd-boot (bootctl install — full BLS)
Kernel	Linux 6.19.0, custom build (no riscv64 RPM in Fedora repos)
initrd	None — rootfs-path drivers built-in (=y)
root=	Block device path required
Rootfs	SD card, ext4
efivarfs	rw (EFI_RT_VOLATILE_STORE=y)

Orange Pi RV (StarFive JH7110, riscv64) — ✅ Fedora 43

Stage	Detail
Boot ROM	JH7110 — partition type GUID
SPL	U-Boot SPL v2026.01, SPI NOR
Secure firmware	OpenSBI v1.8.1, embedded in U-Boot FIT
Bootloader	U-Boot v2026.01, SPI NOR
Boot manager	systemd-boot (fallback path)
Kernel	Linux 6.19.0, custom build (no riscv64 RPM in Fedora repos)
initrd	None — rootfs-path drivers built-in (=y)
root=	Block device path required
Rootfs	NVMe, ext4
efivarfs	ro (EFI_RT_VOLATILE_STORE not set)

ASUS Tinker Board 3 (RK3566, aarch64) — ⚠️ On hold — ethernet DMA

Stage	Detail
Boot ROM	RK3566 — raw offset, sector 64
SPL	idbloader (DDR init + SPL), SD card raw
Secure firmware	TF-A BL31, embedded in idbloader/FIT
Bootloader	U-Boot v2024.x, SD card raw
Boot manager	systemd-boot (bootctl install — full BLS)
Kernel	Linux 7.0-rc4, Fedora-packaged
initrd	dracut (via kernel-install, automatic)
root=	UUID safe
Rootfs	SD card, ext4
efivarfs	rw

Raspberry Pi 3 Model B (BCM2837, aarch64) — ✅ Fedora 43

Stage	Detail
Boot ROM	BCM2837 — VideoCore GPU ROM, FAT files
SPL	bootcode.bin + start.elf (GPU firmware)
Secure firmware	None — GPU handles ARM core release
Bootloader	U-Boot v2026.01, FAT file (loaded as "kernel" by GPU)
Boot manager	systemd-boot (fallback path)
Kernel	Linux 6.19.11, Fedora-packaged
initrd	dracut (via kernel-install, automatic)
root=	UUID safe
Rootfs	SD card, ext4
efivarfs	rw (EFI_RT_VOLATILE_STORE=y)

Orange Pi Zero 3 (Allwinner H618, aarch64) — ✅ Fedora 43

Stage	Detail
Boot ROM	H618 (sunxi) — raw offset, sector 16; GPT entry array relocated to sector 2210
SPL	U-Boot SPL v2026.04, SD card sector 16 (raw)
Secure firmware	TF-A BL31 v2.12.0, embedded in U-Boot FIT
Bootloader	U-Boot v2026.04, SD card raw
Boot manager	systemd-boot (fallback path — efivarfs ro)
Kernel	Linux 7.0.0-rc6, custom build (no H618 DTB in Fedora aarch64 kernel package)
initrd	dracut (QEMU aarch64 chroot on builder VM)
root=	Block device path (/dev/mmcblk0p2)
Rootfs	SD card, ext4
efivarfs	ro (EFI_RT_VOLATILE_STORE not set)

Architecture Notes

RISC-V — JH7110 (Milk-V Mars, Orange Pi RV)

• Boot ROM discovery — partition type GUID, not sector offset. Incorrect GUIDs produce silent failure with no error output. SPL GUID: 2E54B353-1271-4842-806F-E436D6AF6985 U-Boot FIT GUID: BC13C2FF-59E6-4262-A352-B275FD6F7172
• Secure firmware — OpenSBI (RISC-V SBI spec), embedded in U-Boot FIT.
• Custom kernel (packaging gap) — no riscv64 kernel RPM in standard Fedora repos. All rootfs-path drivers must be built-in (=y) — no initrd means no module loading before rootfs mount.
• SPI NOR reflash — use U-Boot sf update, never dd to /dev/mtdX. NOR flash requires erase before write; dd corrupts silently.
• efivarfs — CONFIG_EFI_RT_VOLATILE_STORE=y required for writable efivarfs.
• root= cmdline — explicit block device path required, not UUID.

AArch64 — RK3399 / RK3566 (Rock Pi 4 Plus, Tinker Board 3)

• Boot ROM discovery — raw sector offset (sector 64). Partitions must start at sector 32768 or later. sgdisk --zap-all overwrites sector 64 — reflash U-Boot after any repartition.
• Secure firmware — TF-A BL31 (ARM TrustZone), embedded in U-Boot FIT.
• TF-A build (RK3399) — requires Cortex-M0 cross-compiler for PMU firmware. Use M0_CROSS_COMPILE=arm-linux-gnu- (Fedora ships arm-linux-gnu-gcc; arm-none-eabi-gcc is not available in Fedora repos).
• Kernel — Fedora-packaged aarch64 kernel. dnf update kernel automatic.
• Kernel/DTB pairing — BSP kernel requires BSP DTB; mainline kernel requires mainline DTB. Mixing produces an uninformative panic.

AArch64 — BCM2837 (Raspberry Pi 3B)

• Boot ROM — VideoCore GPU ROM; boots from FAT files, not raw sector offset. No idbloader, no SPI NOR, no way to bypass the GPU firmware stage.
• Partition table — GPT + hybrid MBR required. The GPU ROM reads the MBR to find the FAT partition; pure GPT silently fails. Use gdisk r → h to overlay a legacy MBR type 0x0C entry. RPi 4/5 do not require this.
• GPU firmware modifies the DTB — dtoverlay=disable-bt in config.txt required for correct sdhost configuration in 64-bit mode.
• kernel-modules required — install kernel-core and kernel-modules. dracut initramfs must include: bcm2835-dma bcm2835 mmc_core mmc_block.
• Serial console — Mini-UART (ttyS0), not PL011 (wired to Bluetooth). core_freq=250 in config.txt required for stable baud rate.

AArch64 — H618 (Orange Pi Zero 3)

• Boot ROM discovery — raw sector offset (sector 16). The standard GPT partition entry array (sectors 2–33) overlaps this offset. Solution: sgdisk -j 2210 relocates the entry array past the end of the U-Boot binary. Write U-Boot last — any partition operation after the dd overwrites sector 16.
• Secure firmware — TF-A BL31 (ARM TrustZone), embedded in U-Boot FIT. Build with PLAT=sun50i_h616 (covers H616 and H618).
• U-Boot SPL config overrides — not in defconfig defaults; must set after make defconfig:

  CONFIG_SPL_SYS_MALLOC_F_LEN=0x10000
  CONFIG_SPL_STACK_R_MALLOC_SIMPLE_LEN=0x200000
  CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR=0x50
  

• Custom kernel (packaging gap) — H618 DTS is in mainline from 6.1 onward but not yet in the Fedora aarch64 kernel package. dracut works normally; initramfs built in a QEMU aarch64 chroot on the builder VM.
• zram — mask systemd-zram-setup@zram0.service and zram-generator.service. Masking dev-zram0.device alone is insufficient — the generator instantiates the setup service directly under /run/systemd/generator/ at boot.

Build Environment

Builds use mainline sources:

• riscv64: RISC-V builder VM (x86_64 host, riscv64 cross-compiler), U-Boot v2026.01, OpenSBI v1.8.1, Linux v6.19
• aarch64 (Rockchip): AArch64 builder VM (x86_64 host, aarch64-linux-gnu- cross-compiler), U-Boot v2026.01, TF-A v2.12.0
• aarch64 (BCM2837): Fedora-packaged kernel and U-Boot v2026.01; no custom kernel build required
• Fedora 43 packages from riscv-kojipkgs.fedoraproject.org (riscv64) and standard Fedora mirrors (aarch64)