So far, IGD-specific quirks all require enabling legacy mode, which is
toggled by assigning IGD to 00:02.0. However, some quirks, like the BDSM
and GGC register quirks, should be applied to all supported IGD devices.
A new config option, x-igd-legacy-mode=[on|off|auto], is introduced to
control the legacy mode only quirks. The default value is "auto", which
keeps current behavior that enables legacy mode implicitly and continues
on error when all following conditions are met.
* Machine type is i440fx
* IGD device is at guest BDF 00:02.0
If any one of the conditions above is not met, the default behavior is
equivalent to "off", QEMU will fail immediately if any error occurs.
Users can also use "on" to force enabling legacy mode. It checks if all
the conditions above are met and set up legacy mode. QEMU will also fail
immediately on error in this case.
Additionally, the hotplug check in legacy mode is removed as hotplugging
IGD device is never supported, and it will be checked when enabling the
OpRegion quirk.
Signed-off-by: Tomita Moeko <tomitamo...@gmail.com>
---
hw/vfio/igd.c | 127 +++++++++++++++++++++++++++++---------------------
hw/vfio/pci.c | 2 +
hw/vfio/pci.h | 1 +
3 files changed, 77 insertions(+), 53 deletions(-)
diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
index f5e19f1241..ac096e2eb5 100644
--- a/hw/vfio/igd.c
+++ b/hw/vfio/igd.c
@@ -15,6 +15,7 @@
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
+#include "hw/boards.h"
#include "hw/hw.h"
#include "hw/nvram/fw_cfg.h"
#include "pci.h"
@@ -432,9 +433,7 @@ void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
* bus address.
*/
if (!vfio_pci_is(vdev, PCI_VENDOR_ID_INTEL, PCI_ANY_ID) ||
- !vfio_is_vga(vdev) || nr != 0 ||
- &vdev->pdev != pci_find_device(pci_device_root_bus(&vdev->pdev),
- 0, PCI_DEVFN(0x2, 0))) {
+ !vfio_is_vga(vdev) || nr != 0) {
return;
}
@@ -482,14 +481,13 @@ void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, bdsm_quirk, next);
}
-bool vfio_probe_igd_config_quirk(VFIOPCIDevice *vdev,
- Error **errp G_GNUC_UNUSED)
+bool vfio_probe_igd_config_quirk(VFIOPCIDevice *vdev, Error **errp)
{
- g_autofree struct vfio_region_info *rom = NULL;
int ret, gen;
uint64_t gms_size;
uint64_t *bdsm_size;
uint32_t gmch;
+ bool legacy_mode_enabled = false;
Error *err = NULL;
/*
@@ -498,9 +496,7 @@ bool vfio_probe_igd_config_quirk(VFIOPCIDevice *vdev,
* PCI bus address.
*/
if (!vfio_pci_is(vdev, PCI_VENDOR_ID_INTEL, PCI_ANY_ID) ||
- !vfio_is_vga(vdev) ||
- &vdev->pdev != pci_find_device(pci_device_root_bus(&vdev->pdev),
- 0, PCI_DEVFN(0x2, 0))) {
+ !vfio_is_vga(vdev)) {
return true;
}
@@ -516,56 +512,67 @@ bool vfio_probe_igd_config_quirk(VFIOPCIDevice *vdev,
return true;
}
- /*
- * Most of what we're doing here is to enable the ROM to run, so if
- * there's no ROM, there's no point in setting up this quirk.
- * NB. We only seem to get BIOS ROMs, so a UEFI VM would need CSM support.
- */
- ret = vfio_get_region_info(&vdev->vbasedev,
- VFIO_PCI_ROM_REGION_INDEX, &rom);
- if ((ret || !rom->size) && !vdev->pdev.romfile) {
- error_report("IGD device %s has no ROM, legacy mode disabled",
- vdev->vbasedev.name);
- return true;
- }
-
- /*
- * Ignore the hotplug corner case, mark the ROM failed, we can't
- * create the devices we need for legacy mode in the hotplug scenario.
- */
- if (vdev->pdev.qdev.hotplugged) {
- error_report("IGD device %s hotplugged, ROM disabled, "
- "legacy mode disabled", vdev->vbasedev.name);
- vdev->rom_read_failed = true;
- return true;
- }
-
gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, 4);
/*
- * If IGD VGA Disable is clear (expected) and VGA is not already enabled,
- * try to enable it. Probably shouldn't be using legacy mode without VGA,
- * but also no point in us enabling VGA if disabled in hardware.
+ * For backward compatibilty, enable legacy mode when
+ * - Machine type is i440fx (pc_piix)
+ * - IGD device is at guest BDF 00:02.0
+ * - Not manually disabled by x-igd-legacy-mode=off
*/
- if (!(gmch & 0x2) && !vdev->vga && !vfio_populate_vga(vdev, &err)) {
- error_reportf_err(err, VFIO_MSG_PREFIX, vdev->vbasedev.name);
- error_report("IGD device %s failed to enable VGA access, "
- "legacy mode disabled", vdev->vbasedev.name);
- return true;
- }
+ if ((vdev->igd_legacy_mode != ON_OFF_AUTO_OFF) &&
+ !strcmp(MACHINE_GET_CLASS(qdev_get_machine())->family, "pc_piix") &&
+ (&vdev->pdev == pci_find_device(pci_device_root_bus(&vdev->pdev),
+ 0, PCI_DEVFN(0x2, 0)))) {
+ /*
+ * IGD legacy mode requires:
+ * - VBIOS in ROM BAR or file
+ * - VGA IO/MMIO ranges are claimed by IGD
+ * - OpRegion
+ * - Same LPC bridge and Host bridge VID/DID/SVID/SSID as host
+ */
+ g_autofree struct vfio_region_info *rom = NULL;
+
+ legacy_mode_enabled = true;
+ warn_report("IGD legacy mode enabled, "
+ "use x-igd-legacy-mode=off to disable it if unwanted.");
