On Wed, Sep 12, 2018 at 05:30:29PM +0000, Alexander von Gluck IV wrote: > Good morning! > > I'm working through adding support (or at least ignoring) PCI Enhance > Allocation devices under Haiku. > We run into one of these devices, and crash at boot due to attempting to read > an invalid address. > > Our testing showed that with a USB C dongle plugged in, we don't crash. > Without > it plugged in we get > invalid addresses from PCI > > (for a long-drawn out debug ticket, see https://dev.haiku-os.org/ticket/12885 > ) > > > So, i'm trying to see if I can emulate a PCI bridge with EA under QEMU, I > found > this patch, but it seems > it wasn't accepted: > https://lists.gnu.org/archive/html/qemu-devel/2015-05/msg02073.html
v2 never surfaced I think. > My other thought is since I have access to two laptops implementing this, I > could attach the bridge to > qemu via iommu, but the new vfio stuff doesn't seem to work with bridges. :-| It's fixable, AFAIK no one bothered though. BTW old style kvm dev assignment is still around but probably doesn't work with bridges either. > Anyone know of a way to: > * emulate a PCI EA in qemu. Start with above patch, add bios support? > * attach the local PCI EA bridge to qemu to troubleshoot using real hardware. > For context, here is the suspect EA device: > > > (no USB C dongle) > $ lspci -tvnn > -[0000:00]-+-00.0 Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core > Processor Host Bridge/DRAM Registers [8086:1910] > +-1d.6-[06-3e]-- > > vs > > (USB C dongle) > $ lspci -tvnn > -[0000:00]-+-00.0 Intel Corporation Skylake Host Bridge/DRAM Registers > [8086:1904] > +-1d.6-[06-3e]----00.0-[07-3e]--+-00.0-[08]-- > | +-01.0-[09-3d]-- > | \-02.0-[3e]----00.0 Intel Corporation DSL6340 USB 3.1 Controller [Alpine > Ridge] [8086:15b5] > > > The bride is at 1d.6 in it's own IOMMU group: > > IOMMU group 12 > 00:1d.6 PCI bridge [0604]: Intel Corporation 100 Series/C230 Series Chipset > Family PCI Express Root Port #15 [8086:a11e] (rev f1) > > -- Alex
