From: Tomita Moeko <tomitamo...@gmail.com> Introduce x-pci-class-code option to allow users to override PCI class code of a device, similar to the existing x-pci-vendor-id option. Only the lower 24 bits of this option are used, though a uint32 is used here for determining whether the value is valid and set by user.
Additionally, to ensure VGA ranges are only exposed on VGA devices, pci_register_vga() is now called in vfio_pci_config_setup(), after the class code override is completed. This is mainly intended for IGD devices that expose themselves either as VGA controller (primary display) or Display controller (non-primary display). The UEFI GOP driver depends on the device reporting a VGA controller class code (0x030000). Signed-off-by: Tomita Moeko <tomitamo...@gmail.com> Reviewed-by: Alex Williamson <alex.william...@redhat.com> Link: https://lore.kernel.org/qemu-devel/20250708145211.6179-1-tomitamo...@gmail.com Signed-off-by: Cédric Le Goater <c...@redhat.com> --- hw/vfio/pci.h | 6 ++---- hw/vfio/pci.c | 29 +++++++++++++++++++++++++---- hw/vfio/trace-events | 1 + 3 files changed, 28 insertions(+), 8 deletions(-) diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h index 495fae737d3a2e455e1cc04e062b9860196899be..4aa64611171d310de73d00d6c5be059dcb7bfe49 100644 --- a/hw/vfio/pci.h +++ b/hw/vfio/pci.h @@ -157,6 +157,7 @@ struct VFIOPCIDevice { uint32_t device_id; uint32_t sub_vendor_id; uint32_t sub_device_id; + uint32_t class_code; uint32_t features; #define VFIO_FEATURE_ENABLE_VGA_BIT 0 #define VFIO_FEATURE_ENABLE_VGA (1 << VFIO_FEATURE_ENABLE_VGA_BIT) @@ -205,10 +206,7 @@ static inline bool vfio_pci_is(VFIOPCIDevice *vdev, uint32_t vendor, uint32_t de static inline bool vfio_is_vga(VFIOPCIDevice *vdev) { - PCIDevice *pdev = &vdev->pdev; - uint16_t class = pci_get_word(pdev->config + PCI_CLASS_DEVICE); - - return class == PCI_CLASS_DISPLAY_VGA; + return (vdev->class_code >> 8) == PCI_CLASS_DISPLAY_VGA; } /* MSI/MSI-X/INTx */ diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 1093b28df7c3f5f37e622e6d76a99ad8d2b7e01e..910042c6c2049fc5ee1e635cc74989769b965b76 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -2893,10 +2893,6 @@ bool vfio_populate_vga(VFIOPCIDevice *vdev, Error **errp) "vfio-vga-io@0x3c0", QEMU_PCI_VGA_IO_HI_SIZE); - pci_register_vga(&vdev->pdev, &vdev->vga->region[QEMU_PCI_VGA_MEM].mem, - &vdev->vga->region[QEMU_PCI_VGA_IO_LO].mem, - &vdev->vga->region[QEMU_PCI_VGA_IO_HI].mem); - return true; } @@ -3228,6 +3224,23 @@ bool vfio_pci_config_setup(VFIOPCIDevice *vdev, Error **errp) vdev->sub_device_id); } + /* + * Class code is a 24-bit value at config space 0x09. Allow overriding it + * with any 24-bit value. + */ + if (vdev->class_code != PCI_ANY_ID) { + if (vdev->class_code > 0xffffff) { + error_setg(errp, "invalid PCI class code provided"); + return false; + } + /* Higher 24 bits of PCI_CLASS_REVISION are class code */ + vfio_add_emulated_long(vdev, PCI_CLASS_REVISION, + vdev->class_code << 8, ~0xff); + trace_vfio_pci_emulated_class_code(vbasedev->name, vdev->class_code); + } else { + vdev->class_code = pci_get_long(pdev->config + PCI_CLASS_REVISION) >> 8; + } + /* QEMU can change multi-function devices to single function, or reverse */ vdev->emulated_config_bits[PCI_HEADER_TYPE] = PCI_HEADER_TYPE_MULTI_FUNCTION; @@ -3257,6 +3270,12 @@ bool vfio_pci_config_setup(VFIOPCIDevice *vdev, Error **errp) vfio_bars_register(vdev); + if (vdev->vga && vfio_is_vga(vdev)) { + pci_register_vga(&vdev->pdev, &vdev->vga->region[QEMU_PCI_VGA_MEM].mem, + &vdev->vga->region[QEMU_PCI_VGA_IO_LO].mem, + &vdev->vga->region[QEMU_PCI_VGA_IO_HI].mem); + } + return true; } @@ -3643,6 +3662,8 @@ static const Property vfio_pci_dev_properties[] = { sub_vendor_id, PCI_ANY_ID), DEFINE_PROP_UINT32("x-pci-sub-device-id", VFIOPCIDevice, sub_device_id, PCI_ANY_ID), + DEFINE_PROP_UINT32("x-pci-class-code", VFIOPCIDevice, + class_code, PCI_ANY_ID), DEFINE_PROP_UINT32("x-igd-gms", VFIOPCIDevice, igd_gms, 0), DEFINE_PROP_UNSIGNED_NODEFAULT("x-nv-gpudirect-clique", VFIOPCIDevice, nv_gpudirect_clique, diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index 8ec0ad0cde064927f58fbd8459413b303d155979..fc6ed230d0c89d4b94e5878043bc23d94dcfe737 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -48,6 +48,7 @@ vfio_pci_emulated_vendor_id(const char *name, uint16_t val) "%s 0x%04x" vfio_pci_emulated_device_id(const char *name, uint16_t val) "%s 0x%04x" vfio_pci_emulated_sub_vendor_id(const char *name, uint16_t val) "%s 0x%04x" vfio_pci_emulated_sub_device_id(const char *name, uint16_t val) "%s 0x%04x" +vfio_pci_emulated_class_code(const char *name, uint32_t val) "%s 0x%06x" # pci-quirks.c vfio_quirk_rom_in_denylist(const char *name, uint16_t vid, uint16_t did) "%s %04x:%04x" -- 2.50.1
