This patch set (available at git://github.com/cohuck/qemu pci-tcg)
wires up zpci under tcg. A guest started with

qemu-system-s390x -M s390-ccw-virtio,accel=tcg -cpu qemu,zpci=on -device virtio-net-pci (...)

and a 4.15 kernel in the guest (needed because the requirement for ais
was dropped with

commit 48070c73058be6de9c0d754d441ed7092dfc8f12
Author: Christian Borntraeger <borntraeger@de.ibm.com>
Date:   Mon Oct 30 14:38:58 2017 +0100

    s390/pci: do not require AIS facility

and we don't have a working ais with tcg yet), I get sensible output
out of lspci.

RFC because I'm not sure that I put up the tcg wires in the best way.

Cornelia Huck (2):
  s390x/tcg: wire up pci instructions
  s390x/cpumodel: allow zpci features in qemu model

 target/s390x/gen-features.c |   3 ++
 target/s390x/helper.h       |   9 ++++
 target/s390x/insn-data.def  |  13 +++++
 target/s390x/misc_helper.c  | 123 ++++++++++++++++++++++++++++++++++++++++++++
 target/s390x/translate.c    | 123 ++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 271 insertions(+)

-- 
2.13.6