Hot reset PCIe Device

pci_reset.sh

#!/bin/bash

# Performs the function of resetting a PCI device
#
# Get PCI devices (grab the address in first column):
# lspci
#
# Usage:
# ./pci_reset.sh "86:00.0"
#
# Stolen from here: https://alexforencich.com/wiki/en/pcie/hot-reset-linux


dev=$1
 
if [ -z "$dev" ]; then
    echo "Error: no device specified"
    exit 1
fi
 
if [ ! -e "/sys/bus/pci/devices/$dev" ]; then
    dev="0000:$dev"
fi
 
if [ ! -e "/sys/bus/pci/devices/$dev" ]; then
    echo "Error: device $dev not found"
    exit 1
fi
 
port=$(basename $(dirname $(readlink "/sys/bus/pci/devices/$dev")))
 
if [ ! -e "/sys/bus/pci/devices/$port" ]; then
    echo "Error: device $port not found"
    exit 1
fi
 
echo "Removing $dev..."
 
echo 1 > "/sys/bus/pci/devices/$dev/remove"
 
echo "Performing hot reset of port $port..."
 
bc=$(setpci -s $port BRIDGE_CONTROL)
 
echo "Bridge control:" $bc
 
setpci -s $port BRIDGE_CONTROL=$(printf "%04x" $(("0x$bc" | 0x40)))
sleep 0.01
setpci -s $port BRIDGE_CONTROL=$bc
sleep 0.5
 
echo "Rescanning bus..."
 
echo 1 > "/sys/bus/pci/devices/$port/rescan"