Reset from U-Boot proper gets stuck in SPL

[pamolloy]

=> reset
�esetting ...
U-Boot SPL 2025.07 (Jul 30 2025 - 19:17:06 +0200)
ADI Boot Mode: 0x1 (QSPI Master)
Trying to boot from BOOTROM

• This needs to be tested on an official Yocto release

[jiez]

I spent some time on this issue but have not figured it out.

When u-boot-spl tries to load u-boot from the flash memory chip, the memory mapped SPI flash read returns wrong values. The load instruction at 0x4278 in bootrom should write value 0xad in register w22. But when the error happens, it writes value 0xff in register w22. The value is copied from flash memory through SPI2. The value in flash memory should still be good because it boots OK after hardware reset. So it seems something is wrong after software system reset which causes incorrectly read values from the flash memory.

I checked MMR values for SPI2, PINMUX and CGU, all seem OK.

I tried to read back flash memory from 0x60040000. The first byte of every 16 bytes is 0xff. And the remaining 15 bytes of the first 16 bytes are shifted by one byte. But after that, all data seem wrong.

The next idea I want to try is to use adi_rom_CguInit() and adi_rom_DmcInit() instead of the functions in u-boot.

Another idea is to create a small standalone test case so hardware engineers can take a look.