setdriver

#!/bin/sh
set -e

[ -z "$1" ] && {
  echo >&2 "usage: <command>"
  echo >&2 ""
  echo >&2 "This command can be used to switch a tg3 device between the tg3 driver (for normal use)"
  echo >&2 "and the pci-stub driver (which does nothing for the device and ensures that the kernel"
  echo >&2 "doesn't try and fiddle with it while one is messing with it. The pci-stub mode can also"
  echo >&2 "be used to pass the device through to a qemu/KVM virtual machine."
  echo >&2 ""
  echo >&2 "commands:"
  echo >&2 "  stub <pci-addr>    - assign a device to the pci-stub driver"
  echo >&2 "  virt <pci-addr>    - assign a device to the vfio-pci driver"
  echo >&2 "  tg3  <pci-addr>    - assign a device to the tg3 driver"
  echo >&2 "  reset <pci-addr>   - reset a PCI device"
  exit 2
}

[ "$(id -u)" -eq 0 ] || {
  echo >&2 Must be run as root.
  exit 1
}

case "$1" in
  stub)
    ADDR="$2"
    [ -z "$ADDR" ] && {
      echo >&2 Must specify PCI address.
      exit 1
    }

    modprobe pci_stub
    VENDOR_ID="$(cat /sys/bus/pci/devices/"$ADDR"/vendor)"
    DEVICE_ID="$(cat /sys/bus/pci/devices/"$ADDR"/device)"
    echo "$VENDOR_ID $DEVICE_ID" > /sys/bus/pci/drivers/pci-stub/new_id
    [ -e "/sys/bus/pci/devices/$ADDR/driver/unbind" ] && {
      echo "$ADDR" > /sys/bus/pci/devices/"$ADDR"/driver/unbind
    }
    echo pci-stub > /sys/bus/pci/devices/"$ADDR"/driver_override
    echo "$ADDR" > /sys/bus/pci/drivers/pci-stub/bind
    ;;

  virt)
    ADDR="$2"
    [ -z "$ADDR" ] && {
      echo >&2 Must specify PCI address.
      exit 1
    }

    modprobe vfio-pci
    [ -e "/sys/bus/pci/devices/"$ADDR"/vendor" ] || {
      echo >&2 Bad PCI address.
      exit 1
    }

    echo vfio-pci > /sys/bus/pci/devices/"$ADDR"/driver_override
    [ -e "/sys/bus/pci/devices/$ADDR/driver/unbind" ] && {
      echo "$ADDR" > /sys/bus/pci/devices/"$ADDR"/driver/unbind
    }
    echo "$ADDR" > /sys/bus/pci/drivers_probe
    #drivers/vfio-pci/bind
    ;;

  tg3)
    ADDR="$2"
    [ -z "$ADDR" ] && {
      echo >&2 Must specify PCI address.
      exit 1
    }

    echo tg3 > /sys/bus/pci/devices/"$ADDR"/driver_override
    [ -e "/sys/bus/pci/devices/$ADDR/driver/unbind" ] && {
      echo "$ADDR" > /sys/bus/pci/devices/"$ADDR"/driver/unbind
    }
    echo "$ADDR" > /sys/bus/pci/drivers/tg3/bind
    ;;

  reset)
    ADDR="$2"
    [ -z "$ADDR" ] && {
      echo >&2 Must specify PCI address.
      exit 1
    }

    echo 1 > /sys/bus/pci/devices/"$ADDR"/reset
    ;;

  *)
    echo >&2 "Unknown command."
    exit 1
    ;;
esac