we have a custom board with i.MX8MM and it has a 1MB SPI NOR flash connected to the ECSPI1 interface.
In order to boot from SPI NOR, I flashed an image containing only U-Boot SPL with an offset of 0x400 (1 KiB).
This image runs fine, when I put it on the SD-card with an offset of 0x8400 (33 KiB).
The BOOT_CFG in the OTP fuses is set to boot from eMMC and enables the recovery boot from ECSPI1.
With the fuses set and the image in the flash, I can see that the BootROM starts probing the flash device, but the SPL binary does not run (no output on the console).
Peng Fan was so kind to tell me, that NXP is aware of a problem with SPI NOR boot and currently investigating this. I would be very grateful if NXP could share their current status and possible solutions if known.
Kontron Electronics GmbH