We found an issue with the Jetson AGX Xavier that NVIDIA may find interesting.
The problem is Xavier Jetson AGX does not start to operate with some high end SSDs (The setup is just Intel Optane SSD connected to the Xavier).
With some PCIe switches between the NVIDIA and the SSD there is no problem.
Our suspicion is the Xavier’s PCIe 12V is raised after the reset period (PCIe PERST signal) is complete.
That is, an SSD, that requires 12v, will receive the 12v after the 3.3v is up, and reset (PESRT) was complete. That is miss the reset period.
Whereas according to PCIe standard, it should raise the PERST only 100milisec after both 3.3 and 12v are power good.
- Is it a known issue with the NVIDA? Or this sequence is intentional? Can it be changed?
- If this sequence is intentional, can you help us with the reasons for it?
More details from the lab experiments. Xavier perform the following sequence on boot:
TIME0 – PCIe power 3.3V is raised
TIME1 – PCIe PERST is raised
TIME2 – 12V power is raised
TIME1-TIME0 = ~8ms
TIME2-TIME0 = ~300ms