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U boot order change to eMMC

Posted: Sun Sep 08, 2019 1:04 pm
by iryna7
Hi, I'm trying to always boot from eMMC whatever it mounted SD Card. Does anyone know how to change it easily? thanks in advance.

BR

Re: U boot order change to eMMC

Posted: Sun Sep 29, 2019 7:19 am
by v8dave
My board boots from eMMC even with SD card inserted. I am using the Nano PC T3 Plus.

Which board are you using?

Normally the SD only boots when you hold down the BOOT button. This allows you to load from the SD and flash the eMMC.

Re: U boot order change to eMMC

Posted: Sun Sep 29, 2019 7:00 pm
by smithclarkson001
Hi,

I've installed the official Debian Jessie image to the eMMC, using emmc.sh script. System works fine and boots from eMMC as it should, but only if there is no SD card inserted. If there is a SD card inserted during boot, it becomes /dev/mmcblk0 and the boot fails, because it wants to mount root device from /dev/mmcblk0p2, where it doesn't exist.

I think, that the correct solution would be, to switch the order of mmc devices. The eMMC should be first and the SD should be second. I tried to achieve this with switching the parameters for [card0_boot_para]/[card2_boot_para] and [mmc0_para]/[mmc2_para]. After compiling script.bin, boot fails to initialize emmc/sd devices, failing with '[mmc-err] update clock timeout, fatal error'.

So the question is, what am I doing wrong with switching the emmc/sd devices (I'm quite a newbie here...) or is there another option to achieve the same - to boot from eMMC with SD card inserted?

Thanks

Re: U boot order change to eMMC

Posted: Mon Sep 30, 2019 2:30 am
by v8dave
Which board are you using?