Public bug reported: On the Raspberry Pi 5, Ubuntu 26.04 requires a boot EEPROM dated 2025-02-11 or later (LP: #2146383). The root cause of this requirement has been identified and fixed by Raspberry Pi in their kernel tree, but the fix has not yet been picked up by linux-raspi.
Root cause ---------- With the move to 6.18, Raspberry Pi dropped a downstream patch that had been overriding #size-cells in the upstream bcm2712 dts files. Pi 5 EEPROMs older than February 2025 write the CMA "size" (and reserved-memory "reg") properties with a 1-cell size, which the kernel cannot parse with #size-cells = <2>. As a result CMA is not set up correctly and boot stalls / display output freezes early in boot. Upstream fix ------------ Raspberry Pi fixed this with: "of: Improve compatibility with old Pi 5 firmware" (Phil Elwell) https://github.com/raspberrypi/linux/pull/7405 rpi-7.0.y: 88a4289a8ba7261c1a625a22cf986bb2ae91cc31 rpi-6.18.y: ec0e437419f36584a7c75af188a2dc36b764137b It touches arch/arm64/boot/dts/broadcom/bcm2712-ds.dtsi, drivers/of/fdt.c and drivers/of/of_reserved_mem.c. With it, old firmware boots normally and the kernel only logs "firmware out-of-date?" warnings. Home Assistant OS 18.1 shipped this fix (RPi kernel 6.18.34) and it resolved the same problem for their Pi 5 users on old firmware. Current state in Ubuntu ----------------------- I checked the source packages: neither linux-raspi 7.0.0-1020.20 (resolute-updates) nor 7.0.0-1021.21 (resolute-proposed) contains this commit. The changelog shows the last sync with upstream raspberrypi rpi-7.0.y was 2026-04-01; the fix landed on 2026-05-27. Request ------- Please cherry-pick 88a4289a8ba7 into linux-raspi for resolute (or include it in the next rebase to rpi-7.0.y). Why this matters ---------------- Updating the EEPROM is not possible on all boards in the field. Some Pi 5 boards fail to boot with any EEPROM from 2024-09-23 onwards (ACT LED blinks 8 times, SDRAM init failure) and must stay on 2024-09-10 or older, see https://github.com/raspberrypi/rpi-eeprom/issues/761 and https://github.com/raspberrypi/rpi-eeprom/issues/822. My board is one of these. With this fix such boards could run 26.04 LTS instead of being stuck on an unsupported release. It would also make the kernel more robust for anyone who has not yet updated their EEPROM. My system --------- Board: Raspberry Pi 5 Current bootloader: [sudo rpi-eeprom-update *** UPDATE AVAILABLE *** Run "sudo rpi-eeprom-update -a" to install this update now. To configure the bootloader update policy run "sudo raspi-config" BOOTLOADER: update available CURRENT: Tue Sep 10 13:40:30 UTC 2024 (1725975630) LATEST: Mon Dec 8 19:29:54 UTC 2025 (1765222194) RELEASE: critical (/usr/lib/firmware/raspberrypi/bootloader-2712/critical) Use raspi-config to change the release. ] Currently running: Ubuntu 25.10, kernel [6.17.0-1021-raspi] ** Affects: linux-raspi (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2170238 Title: Missing RPi commit "of: Improve compatibility with old Pi 5 firmware" - 7.0 kernel can't boot on Pi 5 with pre-2025-02 EEPROM To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/2170238/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
