A20-OLinuXino-LIME2-eMMC randomly reboot

[nabbal]

Hello,

I have a brand new board (lime2 eMMC rev. G) with the latest Olimex image (release 9), powered with the SY0605E power supply and connected to a MOD-WIFI-R5370-ANT USB dongle.
The board has a very low load but randomly reboot after a few hours or days.

Does someone have experienced the same issue?

[LubOlimex]

Hello,

Are you booting from a microSD card or from the NAND memory? The NAND install script sets wrong memory clock which might lead to such a problems. We are working on resolving this issue. If you boot from a microSD card continue reading:

Try to plug MOD-WIFI-R5370-ANT to the other USB port, if you haven't already. The USB ports of A20-OLinuXino-LIME2 are configured differently - one is capable of providing 1A of current, while the other only 500mA.

If possible use a back-up Li-Po battery. A20-OLinuXino-LIME2-eMMC has a battery charger, so there is not downside of using a small back-up Li-Po battery all the time.

Finally, consider that USB-WIFI modules like MOD-WIFI-R5370-ANT typically draw a lot of current and also have occasional very high current spikes. It is possible that SY0605E is simply not good enough for your setup. Try a more powerful power supply, for example, capable of providing at 2A at 5V (10W).

Best regards,
Lub/OLIMEX

[nabbal]

Hello,

Thank you very much for your answer.

I boot from the eMMC memory. Does the eMMC install script sets a wrong memory clock also?

I did not know that the 2 USB ports were configured differently, this is good to know, thanks.

I wait for your answer before going further in the investigation (backup battery and more porwerful power supply).

[nabbal]

Hello,

Are you booting from a microSD card or from the NAND memory? The NAND install script sets wrong memory clock which might lead to such a problems. We are working on resolving this issue.

Hello, Could you please confirm that the issue mentioned above also concerned the eMMC install script, and not only the NAND install script?

I have bought a 5V 2A power supply and I am now also using a battery, and I still have some occasional issues.

[LubOlimex]

Hey,

The bug that I mentioned affects only NAND install scripts and boards with NAND memory. Boards with eMMC should not be affected by this bug (the eMMC install is different compared to the NAND install).

I've shared info on how to figure out the memory clock over the e-mail. By the way have you seen this thread: https://www.olimex.com/forum/index.php?topic=2957.0 ?

Best regards,
Lub/OLIMEX

[nabbal]

Hello,

Thank you for your answer.
I checked my mail box including the spam folder, and I don't see any e-mail. Could you please verify it was actually sent?

I did not manage to change the coherent_pool value in uEnv.txt after several attempts.

I finally modified the file /boot/boot.cmd adding coherent_pool=1M at the end of the setenv bootargs line.

Code Select Expand

setenv bootargs console=ttyS0,115200 root=/dev/mmcblk0p2 rootwait panic=10 coherent_pool=1M

Then I did:

Code Select Expand


apt-get install u-boot-tools
mkimage -C none -A arm -T script -d /boot/boot.cmd /boot/boot.scr
reboot


The option is now correctly set:

Code Select Expand


# cat /proc/cmdline
console=ttyS0,115200 root=/dev/mmcblk0p2 rootwait panic=10 coherent_pool=1M

# dmesg|grep coherent
[    0.000000] Kernel command line: console=ttyS0,115200 root=/dev/mmcblk0p2 rootwait panic=10 coherent_pool=1M
[    0.330139] DMA: preallocated 1024 KiB pool for atomic coherent allocations


Let's see if it changes something...