Boot i.MX 8M Plus by sd Card

[Guiyo]

Hi everyone. 

I have a a PCB configure in Boot mode  (Internal Fuses ( BOOT_MOD3 = 0 // BOOT_MOD2 = 0 // BOOT_MOD1 = 0 // BOOT_MOD0 = 0).

It's no possible to change the pin states and it's no possible to programm by USB. 

Is there any option to make the i.MX to boot from sd Card?

Thanks in advance. 

[JorgeCas]

Hello, I hope you are doing well.

You could try to use SD/MMC manufacture mode. When the internal boot and recover boot (if enabled) failed, the boot goes to the SD/MMC manufacture mode before the serial download mode. In the manufacture mode, one bit bus width is used despite of the fuse setting.

By default, the SD/MMC manufacture mode is enabled. Blow the fuse of the RECOVERY_SDMMC_BOOT_DIS to disable it.

Best regards.

[Guiyo]

Hi Jorge Castañeda

First of all thank you for your reply.

We tried everything possible to flash the bootloader and there was no way.

We looked at many forum answers how to force some pins of the uSD to GND and nothing.

The final solution was to drill the PCB and get to pins A72 and A73 and connect them externally to 1.8V.

This way we were able to flash one of the PCBs.

Another PCB I have a new problem because with the same HW and the same uSD it stops at the next point:
U-Boot SPL 2022.04-lf_v2022.04+g181859317b (Nov 15 2022 - 06:28:05 +0000)
DDRINFO: start DRAM init
DDRINFO: DRAM rate 4000MTS
DDRINFO:ddrphy calibration done
DDRINFO: ddrmix config done
SEC0: RNG instantiated
Normal Boot
Trying to boot from BOOTROM
Boot Stage: Recovery boot
image offset 0x8000, pagesize 0x200, ivt offset 0x0
NOTICE: BL31: v2.6(release):automotive-13.0.0_1.1.0-0-g3c1583ba0
NOTICE: BL31: Built : 11:00:38, Nov 21 2022


U-Boot 2022.04-lf_v2022.04+g181859317b (Nov 15 2022 - 06:28:05 +0000)

CPU: i.MX8MP[8] rev1.1 1600 MHz (running at 1200 MHz)
CPU: Industrial temperature grade (-40C to 105C) at 35C
Reset cause: BY
Model: Laird Connectivity i.MX8M Plus Summit SOM
DRAM: 2 GiB
setup_charger: Can't find device id=0x6b
Core: 171 devices, 21 uclasses, devicetree: separate
MMC: FSL_SDHC: 1, FSL_SDHC: 2
Loading Environment from MMC...

New fixes and new problems :S

I hope it's going well

Translated with DeepL.com (free version)