Shutdown Jetson AGX Xavier PCIe power supply

Hi, All!
We build supper fancy SDR AI system based on Jetson AGX Xavier development kit and Xilinx FPGA. Xavier is for CNN inference and Xilinx Alveo U50 acceleration card is for common DSP functions. Yes, I know that we use data center acceleration card with edge device, but we really do need computation power of both of them.
Directly plug Alveo to Xaviers’s PCIe is a bad idea as Xavier can provide only 66W power then Alveo needs 75W. So we going to use PCIe x16 3.0 Expansion Backplane with additional ATX power connector. And provide appropriate power to alveo card from external power supply.
The question is the following. By default Xavier also provides power to PCIe connector and to resolve power supply conflict we need to some how shutdown Xavier power at PCIe connector. Yes, development kit has such option and using gpio we can turn it off. But how can I be sure that some drivers or applications will not hidden turn on it back?

Thanks, for any advices.

Regards, Max

hello m.o.zhegulin,

may I know what’s SDR you’re mention here, is it Software Defined Radio?

please refer to developer guide, you may check PCIe Controller Configuration session for reference,

Hi, Jerry.
Yes, it’s Software Defined Radio.
We use LimeSDR dev board as a radio frontend and Xavier + Alveo for computation platform.

Thanks for reference.

What download is $(KERNEL_TOP) refer to in that reference?

hello felleman,

assume you download the latest r32.6.1 L4T Driver Package (BSP) Sources.
KERNEL_TOP indicate the folder after you extract the kernel_src.tbz2 package.