When ambient temperature is low, the PCI-e link between TK1 and FPGA can not be estiblished.
console message for PCIe bus error:***********
tegra-ubuntu login: root (automatic login)
Last login: Sat Jan 1 00:00:28 UTC 2000 on ttyS0
Welcome to Ubuntu 14.04 LTS (GNU/Linux 3.10.40 armv7l)
- Documentation: https://help.ubuntu.com/
root@tegra-ubuntu:~# [ 27.266404] pcieport 0000:00:00.0: PCIe Bus Error: severity=Corrected, type=Physical Layer, id=0000(Receiver ID)
[ 27.276746] pcieport 0000:00:00.0: device [10de:0e12] error status/mask=00000001/00002000
[ 27.285147] pcieport 0000:00:00.0: [ 0] Receiver Error (First)
After lots of combination of experiments by HW/SW, heat-up/cool-down method at ambient/chip surface/kernal/substrate, we found:
- In defected chip when chip surface temperature is higher than 31℃, the PCI-e link between TK1 and FPGA can be estiblished.
- Good TK1 chip work properly at -10℃ ambient temperature even lower.
- The failure symptom follows CPU, we duplicated it by AB swap approach.
Please help to find the root cause for this issue.