virtio: Add VirtIO PCI modern (V1) support

Use the existing legacy PCI driver as the basis for shared code
between the legacy and modern PCI drivers. The existing virtio_pci
kernel module will contain both the legacy and modern drivers.

Changes to the virtqueue and each device driver (network, block, etc)
for V1 support come in later commits.

Update the MMIO driver to reflect the VirtIO bus method changes, but
the modern compliance can be improved on later.

Note that the modern PCI driver requires bus_map_resource() to be
implemented, which is not the case on all archs.

The hw.virtio.pci.transitional tunable default value is zero so
transitional devices will continue to be driven via the legacy
driver.

Reviewed by: grehan (mentor)
Differential Revision: https://reviews.freebsd.org/D27856

1 files changed, 8 insertions, 0 deletions

diff --git a/sys/dev/virtio/virtio.h b/sys/dev/virtio/virtio.h
index 6628b3765bcd..85160eb18d0d 100644
--- a/sys/dev/virtio/virtio.h
+++ b/sys/dev/virtio/virtio.h
@@ -31,6 +31,7 @@
 #ifndef _VIRTIO_H_
 #define _VIRTIO_H_
 
+#include <dev/virtio/virtio_endian.h>
 #include <dev/virtio/virtio_ids.h>
 #include <dev/virtio/virtio_config.h>
 
@@ -57,6 +58,7 @@ struct vq_alloc_info;
 #define VIRTIO_IVAR_DEVICE		4
 #define VIRTIO_IVAR_SUBVENDOR		5
 #define VIRTIO_IVAR_SUBDEVICE		6
+#define VIRTIO_IVAR_MODERN		7
 
 struct virtio_feature_desc {
 	uint64_t	 vfd_val;
@@ -81,6 +83,10 @@ struct virtio_pnp_match {
 const char *virtio_device_name(uint16_t devid);
 void	 virtio_describe(device_t dev, const char *msg,
 	     uint64_t features, struct virtio_feature_desc *feature_desc);
+uint64_t virtio_filter_transport_features(uint64_t features);
+int	 virtio_bus_is_modern(device_t dev);
+void	 virtio_read_device_config_array(device_t dev, bus_size_t offset,
+	     void *dst, int size, int count);
 
 /*
  * VirtIO Bus Methods.
@@ -88,6 +94,7 @@ void	 virtio_describe(device_t dev, const char *msg,
 void	 virtio_read_ivar(device_t dev, int ivar, uintptr_t *val);
 void	 virtio_write_ivar(device_t dev, int ivar, uintptr_t val);
 uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features);
+int	 virtio_finalize_features(device_t dev);
 int	 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
 	     struct vq_alloc_info *info);
 int	 virtio_setup_intr(device_t dev, enum intr_type type);
@@ -147,6 +154,7 @@ VIRTIO_READ_IVAR(vendor,	VIRTIO_IVAR_VENDOR);
 VIRTIO_READ_IVAR(device,	VIRTIO_IVAR_DEVICE);
 VIRTIO_READ_IVAR(subvendor,	VIRTIO_IVAR_SUBVENDOR);
 VIRTIO_READ_IVAR(subdevice,	VIRTIO_IVAR_SUBDEVICE);
+VIRTIO_READ_IVAR(modern,	VIRTIO_IVAR_MODERN);
 
 #undef VIRTIO_READ_IVAR