MCU Firmware Missing

Legato Application Framework
1

Hi,
Sometimes Mcu Firmware Missing suddendly .

Device Details:
Device: WP7608
Firmware Version: SWI9X07Y_02.16.02.00 000000 jenkins 2018/04/19
19:59:02
Bootloader Version: SWI9X07Y_02.16.02.00 000000 jenkins 2018/04/19
19:59:02
MCU Version: 002.009
Legato Version: 18.06.3_69d8a71199a354ce67a45989abdf0967_modified

Observation:
-Application didn’t crash its working normally
-Manually poweroff and turn on the device MCU firmware is missing
-It will recover once it hard restart the device.

Kindly let me know the reason ASAP
Thanks in advance

2

how about using latest FW R13.x?

3

Currently we are using R16 FW Still we re facing same issue.

4

I don’t see problem:
ati3
Manufacturer: Sierra Wireless, Incorporated
Model: WP7607-1
Revision: SWI9X07Y_02.28.03.05 000000 jenkins 2019/07/08 11:04:16
IMEI: 359780080500170
IMEI SV: 6
FSN: V2842570321010
+GCAP: +CGSM

OK
ati8
Legato Ver: 19.02.0_87cc5f813301994d76389339c0e37301
Yocto Ver: SWI9X07Y_02.28.03.05 2020-10-14_06:19:24
OS Ver: Linux version 3.18.131 (oe-user@oe-host) (gcc version 7.3.0 (GCC) ) #1 PREEMPT Wed May 6 07:24:46 UTC 2020
LK Ver: SWI9X07Y_02.28.03.05
RootFS Ver: SWI9X07Y_02.28.03.05 2020-10-14_06:19:24
UserFS Ver: unknown
MCU Ver: 002.011

OK

Is this only happening to one particular module?

5

It happens randomly …

6

how many module have you tested?

7

Issue has been observed in around 8 modules

8

McuFirmwareMissing
McuFirmwareMissing1366×768 143 KB

For your reference

9

MCU-MISSING
MCU-MISSING911×687 85.9 KB

In R16 Firmware

10

you might contact distributor as this seems to be hardware issue.

11

This issue is likely due to I2C communication failure between the swimcu kernel driver and the MCU.

The workaround is to reboot the module however, be aware a reboot only reboots the MDM, not the MCU.

BR,
Chris

12

What if the issue occurs in the field ? Whether Sierra wireless is working on this issue?
Can we have the resolution in nearby future?

13

Even in R16 also its happenng. still there is no solution provided on this issue. its open from more than an year. Looks like Sierra wireless team is not intrested in fixing this issue. We are facing lot of challenges in the field.

14

Hi Kiran,

For R16 can you let us know the number of devices facing the issue.

Are you referring the same error reported in the link: I2C BUS ERROR:noisy bus/unexpected - Legato Linux distribution (Yocto project) - Legato Forum

The error looks to be different than the previously discussed on this post. Have you tried reproducing the issue on the MangOH Platform.

Btw did you try to verify the issue is from the module by disabling other peripheral I2C devices outside the module?

Thanks & Regards,

Pankaj Sant

15

Dear Pankaj,

The issue is random. We have faced it in more than 100+ devices in the field. Error appears to be similar to what was discussed in the previous version…

16

Dear Kiran,

The previous logs have been posted with older firmware’s for newer firmware we are seeing different logs.

Both the issues do not seem to be similar.

Thanks & Regards,

Pankaj Sant

17

Hi @kiran,

The ARB_LOST issue is separate from the MCU missing issue.

When the system starts, the swimcu kernel driver communicates with the MCU over I2C. If the communication is not established after several attempts, the driver doesn’t try again. The result is the MCU version is never obtained and the resulting peripherals on the MCU are not functional. Ie, ULPM wake up on GPIO.

The simplest workaround is to perform a power cycle or a reboot. A power cycle is not graceful but guarantees the device starts from cold power up.

A reboot might be sufficient, however the potential issue is that only the ARM processor is rebooted, the MCU remains in the same state. Depending on your hardware, rebooting the MCU is either non trivial or impossible, so I recommend power cycling.

BR,
Chris