ARM virt machine boots fail with 14 ioh3420

[Shannon Zhao <zhaoshenglong@huawei.com>]

Hi,

I'm testing the PCIe devices hotplug for ARM virt machine and using
ioh3420 as root port. I found that below command line could work.

qemu-system-aarch64 -machine virt,accel=kvm,usb=off -cpu host -bios
QEMU_EFI.fd -m 12288 -smp 8,sockets=8,cores=1,threads=1  -device
ioh3420,port=0x8,chassis=1,id=pci.1,bus=pcie.0,addr=0x1 -device
ioh3420,port=0x9,chassis=2,id=pci.2,bus=pcie.0,addr=0x2 -device
ioh3420,port=0xa,chassis=3,id=pci.3,bus=pcie.0,addr=0x3 -device
ioh3420,port=0xb,chassis=4,id=pci.4,bus=pcie.0,addr=0x4 -device
ioh3420,port=0xc,chassis=5,id=pci.5,bus=pcie.0,addr=0x5 -device
ioh3420,port=0xd,chassis=6,id=pci.6,bus=pcie.0,addr=0x6 -device
ioh3420,port=0xe,chassis=7,id=pci.7,bus=pcie.0,addr=0x7 -device
ioh3420,port=0xf,chassis=8,id=pci.8,bus=pcie.0,addr=0x8 -device
ioh3420,port=0x10,chassis=9,id=pci.9,bus=pcie.0,addr=0x9 -device
ioh3420,port=0x11,chassis=10,id=pci.10,bus=pcie.0,addr=0xa -device
ioh3420,port=0x12,chassis=11,id=pci.11,bus=pcie.0,addr=0xb -device
ioh3420,port=0x13,chassis=12,id=pci.12,bus=pcie.0,addr=0xc -device
ioh3420,port=0x14,chassis=13,id=pci.13,bus=pcie.0,addr=0xd -device
i82801b11-bridge,id=pci.17,bus=pcie.0,addr=0x11 -device
pci-bridge,chassis_nr=18,id=pci.18,bus=pci.17,addr=0x0 -device
usb-ehci,id=usb,bus=pci.18,addr=0x1 -device
virtio-scsi-pci,id=scsi0,bus=pci.1,addr=0x0,disable-legacy=on,disable-modern=off
-drive
file=/mnt/sdb/guest.raw,format=raw,if=none,id=drive-scsi0-0-0-0,cache=none,aio=native
-device
scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1
-netdev tap,id=hostnet1,vhost=on -device
virtio-net-pci,netdev=hostnet1,id=net1,mac=00:16:3e:2b:cc:e1,bus=pci.2,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet2,vhost=on -device
virtio-net-pci,netdev=hostnet2,id=net2,mac=00:16:3e:22:29:80,bus=pci.3,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet3,vhost=on -device
virtio-net-pci,netdev=hostnet3,id=net3,mac=00:16:3e:28:07:9a,bus=pci.4,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet4,vhost=on -device
virtio-net-pci,netdev=hostnet4,id=net4,mac=00:16:3e:3d:cd:b6,bus=pci.5,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet5,vhost=on -device
virtio-net-pci,netdev=hostnet5,id=net5,mac=00:16:3e:64:9f:b0,bus=pci.6,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet6,vhost=on -device
virtio-net-pci,netdev=hostnet6,id=net6,mac=00:16:3e:33:5b:d3,bus=pci.7,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet7,vhost=on -device
virtio-net-pci,netdev=hostnet7,id=net7,mac=00:16:3e:39:7c:df,bus=pci.8,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet8,vhost=on -device
virtio-net-pci,netdev=hostnet8,id=net8,mac=00:16:3e:0a:c1:4e,bus=pci.9,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet9,vhost=on -device
virtio-net-pci,netdev=hostnet9,id=net9,mac=00:16:3e:0a:58:a6,bus=pci.10,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet10,vhost=on -device
virtio-net-pci,netdev=hostnet10,id=net10,mac=00:16:3e:35:b5:80,bus=pci.11,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet11,vhost=on -device
virtio-net-pci,netdev=hostnet11,id=net11,mac=00:16:3e:4d:b5:bb,bus=pci.12,addr=0x0,disable-legacy=on,disable-modern=off
-netdev tap,id=hostnet12,vhost=on -device
virtio-net-pci,netdev=hostnet12,id=net12,mac=00:16:3e:3b:69:e9,bus=pci.13,addr=0x0,disable-legacy=on,disable-modern=off
-nographic

But if I add one more ioh3420 device by appending above command with
"-device ioh3420,port=0x15,chassis=14,id=pci.14,bus=pcie.0,addr=0xe",
the guest can't boot. It seems that the firmware doesn't recognize the
PCIe devices and print "Connect: PciRoot(0x0): Not Found".

I'm using QEMU 2.8.1 and edk2 at commit 36a0d5c. Is there any limitation
of the supported PCIe devices?

Thanks,
-- 
Shannon