i.MX95 Boot ROM does not fall back from eMMC Boot0 to Boot1 after AHAB container corruption

[arun16598]

Hello Experts,

On the i.MX95, does the Boot ROM support automatic failover between eMMC Boot0 and Boot1 when the selected boot partition contains an invalid AHAB container?

I programmed the same flash.bin into both Boot0 and Boot1. After setting BOOT_PARTITION_ENABLE = Boot0, I corrupted the first 4 KB of Boot0 (destroying the beginning of the AHAB container). The board reports:

Boot stage: Primary
Image set: 0
Parse seco container failed -14
SPL: failed to boot from all boot devices

If I manually switch BOOT_PARTITION_ENABLE to Boot1, the board boots normally.

Based on some older i.MX8 forum discussions, I expected the ROM to automatically try Boot1. Is automatic Boot0→Boot1 fallback supported on i.MX95? If so, what conditions trigger it? If not, what is the recommended redundancy mechanism for bootloader recovery?

Steps for reproduction:

1. Flash the same imx-boot-imx95-19x19-verdin-sd.bin-flash_all to eMMC Boot0 and Boot1. Following is the script that I have used to flash both banks of emmc (attached in attachments)
2. Verify both partitions contain the same image.

3. Set:

   mmc partconf 0 0 1 0

   (Boot0 selected)

4. Corrupt the first 4 KB of Boot0:

   dd if=/dev/zero of=/dev/mmcblk0boot0 bs=512 count=8 conv=fsync

5. Reboot.

6. Observe:

   U-Boot SPL 2025.04-g99518e6b6f20 (Feb 02 2026 - 05:52:54 +0000)
   SYS Boot reason: por, origin: -1, errid: -1
   SYS shutdown reason: por, origin: -1, errid: -1
   Normal Boot
   Trying to boot from MMC1
   Boot stage: Primary
   Image set: 0, offset: 0x0
   Parse seco container failed -14
   Load image from MMC/SD 0x0
   mmc_load_image_raw_sector: mmc block read error
   Error: -38
   SPL: failed to boot from all boot devices
   ### ERROR ### Please RESET the board ###
   

7. Change PARTITION_CONFIG to Boot1:

   mmc partconf 0 0 2 0

8. The board boots successfully from Boot1.

In short, I would like to get clarification on the following 
Does the i.MX95 Boot ROM support automatic eMMC Boot0↔Boot1 failover, or is the redundancy mechanism expected to be implemented differently (e.g., via image sets, software updates, or an alternate boot device)?

BR,

Arun Kumar

[Zhiming_Liu]

Hi @arun16598 

The i.MX95 support it, but need SPL support this feature.

Based on what you've described, it appears that the version of U-Boot you're using does not include the following patch.

LFU-890-1 imx: image-container: Support iMX95 and iMX94 secondary boot · nxp-imx/uboot-imx@02d75ab ·...

Best Regards,
Zhiming

[arun16598]

Thank you @ Zhiming_Liu, I would like to understand
Under what conditions does the i.MX95 Boot ROM set boot_stage = Secondary for eMMC Boot0/Boot1?

BR,
Arun Kumar