git: effcd0ded0ef - main - bhyve: assign a valid INTPIN to NVIDIA GPUs

The branch main has been updated by corvink:

URL: https://cgit.FreeBSD.org/src/commit/?id=effcd0ded0ef1c92bef29c1e9bbf517c97bb45b8

commit effcd0ded0ef1c92bef29c1e9bbf517c97bb45b8
Author:     Corvin Köhne <corvink@FreeBSD.org>
AuthorDate: 2022-03-17 12:11:14 +0000
Commit:     Corvin Köhne <corvink@FreeBSD.org>
CommitDate: 2025-09-16 06:55:09 +0000

    bhyve: assign a valid INTPIN to NVIDIA GPUs
    
    When passing an NVIDIA GPU to a Linux VM, the GPU driver refuses to work and
    complains about a missing IRQ:
    
    [ 77.208984] NVRM: Can't find an IRQ for your NVIDIA card!
    [ 77.212697] NVRM: Please check your BIOS settings.
    [ 77.212699] NVRM: [Plug & Play OS] should be set to NO
    [ 77.212700] NVRM: [Assign IRQ to VGA] should be set to YES
    [ 77.212702] nvidia: probe of 0000:00:07.0 failed with error -1
    
    By setting a valid INTPIN in the PCI config space those error messages
    disappear. Additionally, tools like nvidia-smi are able to detect the GPU and
    the GPU driver seems to work properly.
    
    Note that bhyve still doesn't support legacy interrupts. So, the guest
    shouldn't try to use it even though we're assigning an INTPIN.
    
    Reviewed by:            jhb
    Tested by:              chuck
    MFC after:              1 week
    Sponsored by:           Beckhoff Automation GmbH & Co. KG
    Differential Revision:  https://reviews.freebsd.org/D51892
---
 usr.sbin/bhyve/amd64/Makefile.inc    |  1 +
 usr.sbin/bhyve/pci_passthru_quirks.c | 48 ++++++++++++++++++++++++++++++++++++
 2 files changed, 49 insertions(+)

diff --git a/usr.sbin/bhyve/amd64/Makefile.inc b/usr.sbin/bhyve/amd64/Makefile.inc
index 92e53433ff01..50a011ed4bfd 100644
--- a/usr.sbin/bhyve/amd64/Makefile.inc
+++ b/usr.sbin/bhyve/amd64/Makefile.inc
@@ -13,6 +13,7 @@ SRCS+=	\
 	pci_gvt-d.c	\
 	pci_lpc.c	\
 	pci_passthru.c	\
+	pci_passthru_quirks.c	\
 	pctestdev.c	\
 	pm.c		\
 	post.c		\
diff --git a/usr.sbin/bhyve/pci_passthru_quirks.c b/usr.sbin/bhyve/pci_passthru_quirks.c
new file mode 100644
index 000000000000..5ba0e674f311
--- /dev/null
+++ b/usr.sbin/bhyve/pci_passthru_quirks.c
@@ -0,0 +1,48 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 Beckhoff Automation GmbH & Co. KG
+ * Author: Corvin Köhne <c.koehne@beckhoff.com>
+ */
+
+#include <dev/pci/pcireg.h>
+
+#include <errno.h>
+
+#include "pci_passthru.h"
+
+#define PCI_VENDOR_NVIDIA 0x10DE
+
+static int
+nvidia_gpu_probe(struct pci_devinst *const pi)
+{
+	struct passthru_softc *sc;
+	uint16_t vendor;
+	uint8_t class;
+
+	sc = pi->pi_arg;
+
+	vendor = pci_host_read_config(passthru_get_sel(sc), PCIR_VENDOR, 0x02);
+	if (vendor != PCI_VENDOR_NVIDIA)
+		return (ENXIO);
+
+	class = pci_host_read_config(passthru_get_sel(sc), PCIR_CLASS, 0x01);
+	if (class != PCIC_DISPLAY)
+		return (ENXIO);
+
+	return (0);
+}
+
+static int
+nvidia_gpu_init(struct pci_devinst *const pi, nvlist_t *const nvl __unused)
+{
+	pci_set_cfgdata8(pi, PCIR_INTPIN, 1);
+
+	return (0);
+}
+
+static struct passthru_dev nvidia_gpu = {
+	.probe = nvidia_gpu_probe,
+	.init = nvidia_gpu_init,
+};
+PASSTHRU_DEV_SET(nvidia_gpu);