[RESOLVED] Power down of DPX2 ACh

Autonomous Vehicles DRIVE PX2 DRIVE Hardware
#1

Hello,

After reading the Drive docs and forum posts on safe shutdown of DPX2 (https://devtalk.nvidia.com/default/topic/1016349/ and https://devtalk.nvidia.com/default/topic/1029601/), I have the following questions:
(1) Should I execute the “shutdown -h now” command on both Tegra A and Tegra B?
(2) How exactly is the “power [a|b|ab] off” command executed through Aurix different from the “shutdown -h now” command executed on the Tegra devices?
(3) Is there also a guideline to safely turn off the Aurix device? Or do I just turn off the power supply?

Thanks and Regards,
Sagar

#2

Dear sagar.kirtany,

(1) Should I execute the “shutdown -h now” command on both Tegra A and Tegra B?
(2) How exactly is the “power [a|b|ab] off” command executed through Aurix different from the “shutdown -h now” command executed on the Tegra devices?
(3) Is there also a guideline to safely turn off the Aurix device? Or do I just turn off the power supply?

Here’s how I suggest turning off the power.

  1. Yes, execute “shutdown -h now” command on both Tegra A and Tegra B.
  2. On Aurix console, shell>power ab off : Even if you did the above, the actual TegraA&B will not be turned off. Therefore, turn off the TegraA&B in the second way.
  3. Turn off the power supply.
#3

Thank you for your reply.

But this seems kind of wasteful in terms of the peripherals I need to attach to the dev kit for a safe power down sequence, isn’t it? Because this would require that I connect USB3.0 hubs (mouse+kb) for both Tegra cores, as also displays. So here is a query - hot-swap the USB3.0 hub and the HDMI cable from the Tegra A ports to the Tegra B ports, after I execute shutdown on Tegra A? Just wondering…

#4

Dear sagar.kirtany,

How about turning off TegraA/B using the minicom on host PC? Thanks.

#5

Dear Steve,

Are you saying that I can simply skip the Tegra shutdown and just use Minicom to safely power down the PX2?

Thanks.

#6

Dear sagar.kirtany,

When all tasks are complete on TegraA/B, you execute “shut down - h now” via minicom on the Host PC to turn the Tegras power off. Thanks.

#7

Dear Steve,

I am trying your recommendations without any cameras connected to my DPX2.

When I execute the shutdown command for Tegra A/B via Minicom, everything else looks alright, but the final three lines of the output show something like this:
[ XYZ.ABCDEF] reboot: Power down
Warn: TIMEOUT waiting for SCE Acknowledgement
Warn: Unclean SCE reset

Is this an indication of some trouble?

Thank you.

#8

Hello,

Any update on this topic?

Thank you.

#9

Dear sagar.kirtany,

We are checking the symptom and will update. Thanks.

#10

Dear sagar.kirtany,

During shutdown, BPMP(Boot and Power Management Processor) server tries to get SCE acknowledgement by sending a mailbox interrupt.
This handshake was meant to ensure graceful shutdown of camera firmware.

Since safety firmware running in SCE doesn’t have a shutdown sequence, mailbox interrupt is ignored.
This leads to the error message in bug description.

#11

Hello,

I don’t exactly know what SCE refers to, but I will find out. In the meantime, thank you for your help on this topic; I am marking this thread as RESOLVED.