Serial Download Boot on i.MX8MN EVK Board

[Thomas Schaefer]

Hi all,

We are trying to boot our i.MX8MNano UltraLite DDR3L EVK via USB using Serial Download Mode. We are using u-boot v2022.04-rc3 with patches to support DDR3L memory on this eval system.

ATF firmware used is built using imx_5.4.47_2.2.0 branch of imx-atf firmware.
In addition we are using ddr3_[di]mem_1d_201810.bin DDR training images from firmware-imx-8.10 package.

When copying the resulting flash.bin image on SD card or eMMC, the board is booting fine to linux prompt. But when trying to boot that same image via USB when the board is in Serial Download Mode, the board hangs up when ATF firmware (bl31.bin) has finished (I have added some debug prints to BL31 to verify this).

Are the DDR4/LPDDR4 variants of the i.MX8MNano eval kit known to boot in serial download mode?

Best regards,
Thomas

Thomas Schäfer
SW Design Engineer

Kontron Europe GmbH
Heinrich-Barth-Straße 1-1a | 66115 Saarbrücken | Germany
thomas.schaefer at kontron.com