Can't boot from sd-card on BeagleBone Black

[Pavel Yermolenko]

Here is boot log when using u-boot files, originated from u-boot build 
where *am335x_evm_defconfig* file was used as default configuration :

U-Boot SPL 2020.10-rc3-00012-g9f04a634ef (Aug 29 2020 - 11:40:17 +0200)
Trying to boot from MMC1
U-Boot 2020.10-rc3-00012-g9f04a634ef (Aug 29 2020 - 11:40:17 +0200)
CPU : AM335X-GP rev 2.1
Model: TI AM335x BeagleBone Black
DRAM: 512 MiB
WDT: Started with servicing (60s timeout)
NAND: 0 MiB
MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1
Loading Environment from FAT... *** Warning - bad CRC, using default 
environment
<ethaddr> not set. Validating first E-fuse MAC
Net: eth2: ethernet at 4a100000, eth3: usb_ether
Hit any key to stop autoboot: 0
switch to partitions #0, OK
mmc0 is current device
SD/MMC found on device 0
Failed to load 'boot.scr'
Failed to load 'uEnv.txt'
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:1...
switch to partitions #0, OK
mmc0 is current device
SD/MMC found on device 0
Failed to load '/boot/zImage'
switch to partitions #0, OK
mmc1(part 0) is current device
Scanning mmc 1:1...
Found /boot/extlinux/extlinux.conf

The last line "Found /boot/extlinux/extlinux.conf" signifies, that boot 
process from sd-card failed and BBB switched to eMMC (where 
*extlinux.conf* indeed does exist) and then successfully boots from eMMC.

What's wrong with SD card ?

Thanks.


On 30/08/2020 19:47, Peter Robinson wrote:
> On Sun, Aug 30, 2020 at 6:41 PM Pavel Yermolenko <py.missuri at sunrise.ch> wrote:
>> Hello,
>>
>> I've tried two different default configurations while building u-boot:
>>
>>    * am335x_boneblack_vboot_defconfig
>>    * am335x_evm_defconfig
>>
>> I formatted sd-card with this script:
>> https://github.com/PacktPublishing/Mastering-Embedded-Linux-Programming-Second-Edition/blob/master/format-sdcard.sh
>> Then I copied *MLO* and *u-boot.img* into the boot partition.
>> Here is boot log for am335x_boneblack_vboot_defconfig case (for
>> am335x_evm_defconfig it's similar):
>>
>>      |U-Boot SPL 2020.10-rc3 (Aug 28 2020 - 10:16:38 +0200)|
>>      |WDT: Not found!
>>      Trying to boot from MMC1
>>      Loading Environment from FAT... *** Warning - bad CRC, using default
>>      environment
>>      Loading Environment from MMC... *** Warning - bad CRC, using default
>>      environment
>>        U-Boot 2020.10-rc3 (Aug 28 2020 - 10:16:38 +0200)
>>        CPU : AM335X-GP rev 2.1
>>      Model: TI AM335x BeagleBone Black
>>      DRAM: 512 MiB
>>      MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1
>>      Loading Environment from FAT... *** Warning - bad CRC, using default
>>      environment
>>      Loading Environment from MMC... *** Warning - bad CRC, using default
>>      environment
>>        <ethaddr> not set. Validating first E-fuse MAC
>>      Net: eth2: ethernet at 4a100000, eth3: usb_ether
>>      Press SPACE to abort autoboot in 2 seconds
>>      switch to partitions #0, OK
>>      mmc0 is current device
>>      SD/MMC found on device 0
>>      Failed to load 'boot.scr'
>>      Failed to load 'uEnv.txt'
>>      switch to partitions #0, OK
>>      mmc0 is current device
>>      Scanning mmc 0:1...
>>      switch to partitions #0, OK
>>      mmc0 is current device
>>      SD/MMC found on device 0
>>      Failed to load '/boot/zImage'
>>      switch to partitions #0, OK
>>      mmc1(part 0) is current device
>>      Scanning mmc 1:1...
>>      Found /boot/extlinux/extlinux.conf|
>>
>> As you see, it tries to boot from MMC1 (I suppose that it's sd-card), it
>> fails to boot from MMC1, then it switches to eMMC (where is full Linux,
>> i.e. boot + kernel) and boots successfully from eMMC.
>>
>> There are warnings: "bad CRC". Probably this is the cause of boot failure ?
> No, that's just because it can't find a saved environment variables to load.
>
>> Could it be problem of copying of u-boot files ... or erroneous
>> formatting of sd-card.
>> Have someone an idea how to check these issues.
> It looks off a mSD card OK for me, have you tried holding down the
> button (the one near the mSD card) when powering on to tell it to
> force the mSD card?