Booting up issue in i.MX8M EVK for eMMC mode

[saikumarmails]

Hi,

      We want to program the eMMC with our images (Linux, dtb & Root FS) and make the board boot up from SPI-NOR & eMMC combination, but during this process we had below observations and queries.

Environment:

• Board Revision: SCH-29615 REV B4
• SD card is flashed with our custom binary (with U-Boot 2018.03-imx_v2018.03_4.14.78_1.0.0_ga+g7ade5b407f (Jun 09 2020 - 07:17:26 +0000))

Observations:

• Able to probe the flash in u-boot and got the below response

• Able to clear the SPI-NOR flash (/dev/mtd0) from Linux userspace using the dd command and able to verify it using the hexdump

Queries:

• When changed the boot mode switches to boot from eMMC with OFF OFF ON OFF (for SW 801 DIP switches 1 - 4 respectively) we are seeing logs of old version of u-boot (U-Boot 2017.03 (Apr 11 2018 - 10:04:36 +0800)) which probably had come with the board to boot the Android from eMMC. This behavior is same even after clearing the whole of SPI-NOR (/dev/mtd0) & eMMC memories. Not sure from where we are getting the logs of older u-boot as this mode should boot from SPI-NOR which is completely empty.

Got below logs for the older version of u-boot:

Please let me know for any additional information which might help to answer the query.

Thanks

[igorpadykov]

Hi Venkatasai

reason may be that new image was not properly programmed, one can try to

program it with uuu tool

GitHub - NXPmicro/mfgtools: Freescale/NXP I.MX Chip image deploy tools. 

use guidelines provided in i.MX Linux User’s Guide

Please pay attention to Manufacture Mode

Best regards
igor
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[saikumarmails]

Hi igorpadykov,

      Thanks for the response.

I'll add some details to add more clarity.

I did not program the SPI-NOR flash memory with any image. I cleared the SPI-NOR flash memory and set the target boot mode switches to boot from eMMC. I was expecting the board not to boot as there is no image inside the SPI-NOR flash.

Note: I programmed the custom image inside the SD card and the board booted up well, when the boot mode switches are set to boot from SD.

When I set the boot mode switches to boot from eMMC an older version of u-boot (U-Boot 2017.03) came up. I'm very confused how come the board is booting at all as the SPI-NOR flash memory & the eMMC are completely zeros and the SD card has latest version of u-boot (U-Boot 2018.03-imx_v2018.03), please add clarity.

Is there some other memory the board falls back if there is no image in the SPI-NOR flash in the eMMC boot mode?

Also, is there any other way to program the u-boot without the uuu tool?

Thanks,

Sai