vfio-pci: Fix Nvidia MSI ACK through 0x88000 quirk

When MSI is enabled on Nvidia GeForce cards the driver seems to
acknowledge the interrupt by writing a 0xff byte to the MSI capability
ID register using the PCI config space mirror at offset 0x88000 from
BAR0.  Without this, the device will only fire a single interrupt.
VFIO handles the PCI capability ID/next registers as virtual w/o write
support, so any write through config space is currently dropped.  Add
a check for this and allow the write through the BAR window.  The
registers are read-only anyway.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Alex Williamson 2013-12-06 11:16:23 -07:00
parent 5b49ab188f
commit 96eeeba0db

View File

@ -1811,6 +1811,34 @@ static void vfio_probe_nvidia_bar5_window_quirk(VFIODevice *vdev, int nr)
vdev->host.function);
}
static void vfio_nvidia_88000_quirk_write(void *opaque, hwaddr addr,
uint64_t data, unsigned size)
{
VFIOQuirk *quirk = opaque;
VFIODevice *vdev = quirk->vdev;
PCIDevice *pdev = &vdev->pdev;
hwaddr base = quirk->data.address_match & TARGET_PAGE_MASK;
vfio_generic_quirk_write(opaque, addr, data, size);
/*
* Nvidia seems to acknowledge MSI interrupts by writing 0xff to the
* MSI capability ID register. Both the ID and next register are
* read-only, so we allow writes covering either of those to real hw.
* NB - only fixed for the 0x88000 MMIO window.
*/
if ((pdev->cap_present & QEMU_PCI_CAP_MSI) &&
vfio_range_contained(addr, size, pdev->msi_cap, PCI_MSI_FLAGS)) {
vfio_bar_write(&vdev->bars[quirk->data.bar], addr + base, data, size);
}
}
static const MemoryRegionOps vfio_nvidia_88000_quirk = {
.read = vfio_generic_quirk_read,
.write = vfio_nvidia_88000_quirk_write,
.endianness = DEVICE_LITTLE_ENDIAN,
};
/*
* Finally, BAR0 itself. We want to redirect any accesses to either
* 0x1800 or 0x88000 through the PCI config space access functions.
@ -1837,7 +1865,7 @@ static void vfio_probe_nvidia_bar0_88000_quirk(VFIODevice *vdev, int nr)
quirk->data.address_mask = PCIE_CONFIG_SPACE_SIZE - 1;
quirk->data.bar = nr;
memory_region_init_io(&quirk->mem, OBJECT(vdev), &vfio_generic_quirk,
memory_region_init_io(&quirk->mem, OBJECT(vdev), &vfio_nvidia_88000_quirk,
quirk, "vfio-nvidia-bar0-88000-quirk",
TARGET_PAGE_ALIGN(quirk->data.address_mask + 1));
memory_region_add_subregion_overlap(&vdev->bars[nr].mem,