Hi Fawad, On Sat, Feb 22, 2020 at 12:26 PM Fawad Lateef <fawadlateef@xxxxxxxxx> wrote: > > Hello, > > I am trying to figure-out an issue on our i.MX6Q platform based design > where PCIe interface goes bad. > > We have a Phytec i.MX6Q eMMC SOM, attached to our custom designed > board. PCIe root-complex from i.MX6Q is attached to PLX switch > (PEX8605). > > Linux kernel version is 4.19.9x and also 4.14.134 (from phytec's Does it happen with 5.4 or 5.5 too? Which dts are you using? > Then I enable the #PERST pin of PLX switch, everything is still good > (no rescan on Linux is done yet) > > ~ # echo 139 > /sys/class/gpio/export > ~ # echo out > /sys/class/gpio/gpio139/direction > ~ # echo 1 > /sys/class/gpio/gpio139/value Not sure why you toggle the PERST pin from userspace. You should do it via reset-gpio property in the device tree.
