[Qemu-devel] [PATCH 0/2] add check for PCIe root ports and downstream ports

[arei.gonglei]

From: Gonglei <address@hidden>

Root ports and downstream ports of switches are the hot
pluggable ports in a PCI Express hierarchy. 
PCI Express supports chip-to-chip interconnect, a PCIe link can 
only connect one pci device/Switch/EndPoint or PCI-bridge.

7.3. Configuration Transaction Rules (PCI Express specification 3.0)
7.3.1. Device Number

Downstream Ports that do not have ARI Forwarding enabled must 
associate only Device 0 with the device attached to the Logical Bus
representing the Link from the Port.

Right now, ARI Forwarding dose not support. So, only slot 0 is
supported, regardless of hotplug or coldplug.

So, adding check about slot 0 for PCIe downstream ports and
root ports, which avoid useless operation, both hotplug and
coldplug.

Gonglei (2):
  qdev: Introduce a function to get qbus's parent
  pci: add check for pcie root ports and downstream ports

 hw/core/qdev.c         |  7 +++++++
 hw/pci/pci.c           | 41 +++++++++++++++++++++++++++++++++++++++++
 include/hw/qdev-core.h |  1 +
 3 files changed, 49 insertions(+)

-- 
1.7.12.4