Module Name: src
Committed By: thorpej
Date: Sun Nov 19 19:49:44 UTC 2023
Modified Files:
src/sys/dev/pci: virtio_pci.c
Log Message:
On alpha and sparc64, use VirtIO 1.0 and VIRTIO_F_ACCESS_PLATFORM so
that DMA to PCI-attached VirtIO devices works properly. This is needed
for Qemu to select the appropriate address space for PCI DMA.
To generate a diff of this commit:
cvs rdiff -u -r1.43 -r1.44 src/sys/dev/pci/virtio_pci.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/pci/virtio_pci.c
diff -u src/sys/dev/pci/virtio_pci.c:1.43 src/sys/dev/pci/virtio_pci.c:1.44
--- src/sys/dev/pci/virtio_pci.c:1.43 Fri Jul 7 07:19:36 2023
+++ src/sys/dev/pci/virtio_pci.c Sun Nov 19 19:49:44 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: virtio_pci.c,v 1.43 2023/07/07 07:19:36 rin Exp $ */
+/* $NetBSD: virtio_pci.c,v 1.44 2023/11/19 19:49:44 thorpej Exp $ */
/*
* Copyright (c) 2020 The NetBSD Foundation, Inc.
@@ -28,7 +28,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: virtio_pci.c,v 1.43 2023/07/07 07:19:36 rin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: virtio_pci.c,v 1.44 2023/11/19 19:49:44 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -50,6 +50,15 @@ __KERNEL_RCSID(0, "$NetBSD: virtio_pci.c
#define VIRTIO_PRIVATE
#include <dev/pci/virtiovar.h> /* XXX: move to non-pci */
+#if defined(__alpha__) || defined(__sparc64__)
+/*
+ * XXX VIRTIO_F_ACCESS_PLATFORM is required for standard PCI DMA
+ * XXX to work on these platforms, at least by Qemu.
+ * XXX
+ * XXX Generalize this later.
+ */
+#define __NEED_VIRTIO_F_ACCESS_PLATFORM
+#endif /* __alpha__ || __sparc64__ */
#define VIRTIO_PCI_LOG(_sc, _use_log, _fmt, _args...) \
do { \
@@ -275,8 +284,28 @@ virtio_pci_attach(device_t parent, devic
ret = virtio_pci_attach_10(self, aux);
}
if (ret == 0 && revision == 0) {
- /* revision 0 means 0.9 only or both 0.9 and 1.0 */
+ /*
+ * revision 0 means 0.9 only or both 0.9 and 1.0. The
+ * latter are so-called "Transitional Devices". For
+ * those devices, we want to use the 1.0 interface if
+ * possible.
+ *
+ * XXX Currently only on platforms that require 1.0
+ * XXX features, such as VIRTIO_F_ACCESS_PLATFORM.
+ */
+#ifdef __NEED_VIRTIO_F_ACCESS_PLATFORM
+ /* First, try to attach 1.0 */
+ ret = virtio_pci_attach_10(self, aux);
+ if (ret != 0) {
+ aprint_error_dev(self,
+ "VirtIO 1.0 error = %d, falling back to 0.9\n",
+ ret);
+ /* Fall back to 0.9. */
+ ret = virtio_pci_attach_09(self, aux);
+ }
+#else
ret = virtio_pci_attach_09(self, aux);
+#endif /* __NEED_VIRTIO_F_ACCESS_PLATFORM */
}
if (ret) {
aprint_error_dev(self, "cannot attach (%d)\n", ret);
@@ -781,6 +810,10 @@ virtio_pci_negotiate_features_10(struct
uint64_t host, negotiated, device_status;
guest_features |= VIRTIO_F_VERSION_1;
+#ifdef __NEED_VIRTIO_F_ACCESS_PLATFORM
+ /* XXX This could use some work. */
+ guest_features |= VIRTIO_F_ACCESS_PLATFORM;
+#endif /* __NEED_VIRTIO_F_ACCESS_PLATFORM */
/* notify on empty is 0.9 only */
guest_features &= ~VIRTIO_F_NOTIFY_ON_EMPTY;
sc->sc_active_features = 0;
