CM5 (eMMC) + uConsole: Trixie Fails to Boot After EEPROM Update (2025-11-05) — Anyone Successful?

uConsole
1

Hi everyone,

I’m running into a blocking issue while trying to move from Rex’s Bookworm image to Trixie on my uConsole (CM5 with eMMC), and I’d really appreciate some guidance from anyone who has successfully gone through this on the same hardware configuration.

Below is a summary of what I tested, what worked, and where things started to break.

Hardware setup

  • uConsole

  • Raspberry Pi CM5 (eMMC model, no SD card)

  • Accessing the module through a Waveshare CM5 adapter board in USB mass-storage mode
    (the adapter exposes the eMMC via USB, but does not expose the EEPROM)

Baseline (Working)

I was originally running:

  • Bookworm 6.12.y by Rex

  • Bootloader: factory EEPROM version (whatever shipped originally with the CM5)

  • System boots normally on the uConsole, display OK, no shutdown loop.

I made a full backup image of this working setup.

Objective

Move to:

  • Trixie 6.12.y by Rex,

  • with the updated Raspberry Pi 5 EEPROM required for newer kernels.

Where things started to break

### 1. Installing Trixie directly → device shows boot logo → then auto-shutdown

The uConsole powers on, backlight + ClockworkPi logo appear,
but after a few seconds the device powers off by itself.

I get a repeatable boot–shutdown cycle. No way to reach userspace.

This happens consistently with multiple flashes of the Trixie image.

2. Need for a recent CM5 bootloader

I noticed that Trixie relies on newer kernel/boot features, and several users mentioned needing a newer EEPROM.

I installed the latest EEPROM image:

rpi-boot-eeprom-recovery-2025-11-05-2712

Using Raspberry Pi Imager’s “Bootloader (Pi 5 family) – NVMe/USB” utility image, flashed to the CM5 via USB mass-storage mode.

→ The EEPROM update appears to install correctly

Using strings pieeprom.bin, I can clearly see:

VERSION:57db150d
DATE: 2025/11/05
BOOT_ORDER=0xf146

So the new EEPROM seems to be active.

3. Trixie still does not boot (same shutdown issue)

Even with the updated bootloader:

  • ClockworkPi splash appears

  • Backlight turns on

  • A few seconds later → the whole uConsole shuts down

So the EEPROM update alone does not solve the Trixie boot failure.

4. Restored Bookworm backup → works again

I reflashed my Bookworm backup image onto the CM5 eMMC.

Good news:
→ Bookworm boots again correctly on the uConsole.

However, this time it is using the newer EEPROM, not the original one.

5. New issue: Boot becomes noticeably slower

With the November 2025 EEPROM installed, my uConsole takes significantly longer to start Bookworm.

This was not the case with the original CM5 bootloader.

So at the moment:

  • Bookworm works, but boots slower (likely due to the new boot order / new Pi 5 boot FSM)

  • Trixie does not boot at all, regardless of EEPROM version or config.txt tweaks

Additional notes from testing

:black_small_square: I cannot access the EEPROM via rpiboot

The Waveshare CM5 adapter exposes only the eMMC through USB.
It does not expose the EEPROM partition, so I cannot:

  • read back the EEPROM

  • run rpi-eeprom-config --edit

  • extract pieeprom.bin from the module

This severely limits debugging.

:black_small_square: config.txt tweaks (KMS/FKMS) did not fix the shutdown issue

I tested variants like:

dtoverlay=clockworkpi-uconsole-cm5
dtoverlay=vc4-fkms-v3d-pi5

and disabling watchdog flags, UART, PCIe, etc.

None of these changed the auto-shutdown behavior.

:red_question_mark: My main question to the community

Has anyone with a CM5 (eMMC) successfully installed and booted Rex’s Trixie 6.12.y image on a uConsole?

If yes:

  • Which EEPROM/bootloader version are you using?

  • Did you use the November 2025 bootloader (2025-11-05-2712)?

  • Do you have a working config.txt for CM5 + uConsole?

  • Did you experience the same shutdown behavior during early boot?

  • Is there an updated CM5 EEPROM image compatible with the uConsole that I’m missing?

At this point I want to avoid further low-level experiments unless I know this setup has actually worked for someone.

If anyone (especially Rex or other CM5 users) has insight or a known-good bootloader + config combination for Trixie on CM5 eMMC, I’d be grateful.

Thanks in advance!

2

Your bootloader version is fine. When you flashed Trixie did you apply and custom settings? If so that’s the problem.
If not have you tried redownloading the image maybe the download was corrupted.

3

Hi Rex,

Thanks for the quick reply.

I’ve already tried flashing Trixie both with and without custom settings (after seeing the warnings about that issue), and the behaviour was exactly the same in both cases.
I can reflash the image again, but I’m quite confident that the download wasn’t corrupted.

What worries me more is that—even when going back to Bookworm—the system now takes significantly longer to boot than with the original factory bootloader. The screen stays black for several seconds before the ClockworkPi logo appears. This slower boot happens regardless of the OS image, so it really seems tied to the bootloader behaviour.

Since you mentioned the November 2025 bootloader version is fine, do you have any idea what could cause this slower boot sequence on CM5?
Anything specific I should check in the EEPROM config, DTBs, or kernel loading process?

Also, with the new distribution model where the bootloader is only provided as a .img file, it has become much harder to adjust the bootloader configuration before or after flashing—especially on a CM5 with eMMC, where you can’t easily modify files once the process starts.
Do you have recommendations or an official method for safely editing bootloader settings (config.txt, overrides, etc.) under this new system?

Thanks again for your help.

4

On my emmc cm5 I’ve not had to do anything to the bootloader for it to work. I’m using the stock settings on the eeprom with my emmc cm5.

5

Got it — but just to compare properly: which exact EEPROM version are you running on your eMMC CM5?

I’ve tested both the May 2025 and September 2025 builds, and in both cases only Bookworm boots reliably here. Trixie starts to boot, then shuts itself off before completing.
On top of that, both EEPROM versions give me a long black-screen delay before the ClockworkPi logo — something the factory bootloader didn’t do.

Just trying to understand why yours boots instantly and mine doesn’t.

Thanks!

6

Hi everyone,

I’m posting to share a successful path with the CM5 (eMMC) installed in the uConsole, using Rex’s Trixie 6.12.y image — and to detail exactly what I did so that it works, in case others are still running into the “boot logo → shutdown” or long black-screen issues.

:wrench: My hardware setup

  • uConsole (ClockworkPi)

  • Compute Module 5 (eMMC version, no SD card)

  • Connected via Waveshare CM4-Noan adapter (USB mass-storage mode) to Mac for flashing

:white_check_mark: What worked (baseline)

  • I was originally running Rex’s Bookworm image (6.12.y) with the CM5’s factory EEPROM — everything booted correctly, the display worked, no shutdown loops.

  • I made a backup of this known-working setup.

:bullseye: My objective

  • Move to Rex’s Trixie 6.12.y image

  • Use a suitable bootloader/EEPROM version to support Trixie and the CM5 in this custom board

:red_exclamation_mark: What failed initially

  • I flashed Trixie with the factory EEPROM — the uConsole showed the ClockworkPi logo, then the device powered off after a few seconds (repeatable).

  • I updated the EEPROM to 2025-11-05-2712 (via the NVMe/USB bootloader image)

    • strings pieeprom.bin confirmed VERSION: 2025/11/05 and BOOT_ORDER=0xf146

  • Still: the same shutdown loop persisted.

  • I reverted to Bookworm backup image (now using newer EEPROM) → boots correctly, but boot time is significantly slower than before.

:white_check_mark: What eventually fixed things for me

  1. I downgraded the EEPROM to version 2025-05-08-2712 (or compatible pre-May 2025 build)

  2. After flashing the EEPROM, I used Rex’s Trixie image and it boots fully, no shutdown, display works properly.

  3. My EEPROM config (checked via rpi-eeprom-config) is:

    [all]
BOOT_UART=0
BOOT_ORDER=0xf41
NET_INSTALL_AT_POWER_ON=0
PCIE_PROBE=0
PCIE_DISABLE=1
POWER_OFF_ON_HALT=1

  4. Additionally I modified /boot/firmware/config.txt to disable PCIe (dtparam=pciex1=off) so the board did not hang during hardware init.

  5. Now Trixie boots in the uConsole reliably.

:pushpin: Notes / Observations

  • Even after the downgrade, there is still a slight black-screen delay before the logo (≈2-3 s), likely due to the uConsole’s LCD/DSI pipeline and u-boot initialization — so this may not be fully avoidable in this board layout.

If anyone knows : are there known updates to the bootloader image after May 2025 that avoid the long black-screen or shutdown loop but also still work with uConsole? Also, is there a canonical method to bypass the hidden hardware initialization delay (LCD backlight, device-tree, panel driver) on uConsole CM5?

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