Hi, we are facing unexpected memory failure on imx.6 sololite MCIMX6L3DVN10AA with linux android kitkat

[rammohanbasavar]

Hi,

Hi, we are working with IMX.6 Sololite processor (MCIMX6L3DVN10AA N20G GPU, no EPDC) and facing several memory access failures on linux-android kitkat. we found with same hardware & software design working fine on MCIMX6L8DVN10AB N20G GPU, EPDC.

1. Freescale or other standard reference board used
   1. MCIMX6L3DVN10AA N20G GPU, no EPDC evaluation board
2. Kernel version and/or BSP release used
   1. linux kernel 3.14,
      
3. Any additional software/application or hardware used
   1. android kitkat
4. Expected and observed behavior
   1. after boot up several unexpected memory access failure like NULL pointer dereference, data aborts, page faults are coming. these are not related any specific process context and are coming un expectedly. when we try to enter into suspend-to-RAM, target crashing immediately. we are suspecting it might be an issue with DDR timing.
5. Steps to reproduce
   1. just boot the target
      
6. Frequency of reproducibility (always, usually, sometimes)
   1. always

Can you please suggest any DDR timing initialisations missing in  MCIMX6L3DVN10AA part and provide any kind of experiments to carry out.

Thanks,

Rammohan

Original Attachment has been moved to: hanglog.txt.zip

[saurabh206]

Hi,

You can check the calibration process.

https://community.freescale.com/docs/DOC-96412

Thanks

Saurabh

[rammohanbasavar]

Hi Saurabh,

Thanks for your prompt reply. we do regular DDR stress tests in our R&D and we have carried same with case also successfully.

this issue we are facing specifically on the part (MCIMX6L3DVN10AA N20G GPU, no EPDC), we would like to know any specific changes on this processor part.

Please help us on how to deal this specific hardware related software issue.

Thanks,

Rammohan

[rammohanbasavar]

Hi,

we are using DDR MT42L256M32D2 - 1GB/512MB LPDDR2, 168 pin micron with MCIMX6L8DVN & MCIMX6L3DVN imx6 sololite processors.

None of these part able to boot up with linux(ver. 3.05) + android(Kitkat) and all the time we are facing unexpected memory failures.

Can you please suggest any memory timing tweaks needed for this combination?

Thanks,

Rammohan

[rammohanbasavar]

Hi,

I able to get over the memory failures by putting the target in performance mode..

echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

this clearly indicates that processor clk frequencies are not in sync with DDR timings.

Can any one please suggest desired changes for DDR2 MT42L256M32D2 - 1GB/512MB LPDDR2, 168 pin MICRON with MCIMX6L8DVN & MCIMX6L3DVN imx6 sololite processors.

Thanks,

Rammohan