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, 65 insertions, 11 deletions

diff --git a/sys/dev/virtio/virtio.c b/sys/dev/virtio/virtio.c
index b6537e9305ea..18eace65a12b 100644
--- a/sys/dev/virtio/virtio.c
+++ b/sys/dev/virtio/virtio.c
@@ -60,24 +60,28 @@ static struct virtio_ident {
 	{ VIRTIO_ID_ENTROPY,		"Entropy"			},
 	{ VIRTIO_ID_BALLOON,		"Balloon"			},
 	{ VIRTIO_ID_IOMEMORY,		"IOMemory"			},
-	{ VIRTIO_ID_RPMSG,		"Remote Processor Messaging" 	},
+	{ VIRTIO_ID_RPMSG,		"Remote Processor Messaging"	},
 	{ VIRTIO_ID_SCSI,		"SCSI"				},
 	{ VIRTIO_ID_9P,			"9P Transport"			},
 	{ VIRTIO_ID_RPROC_SERIAL,	"Remote Processor Serial"	},
 	{ VIRTIO_ID_CAIF,		"CAIF"				},
 	{ VIRTIO_ID_GPU,		"GPU"				},
-	{ VIRTIO_ID_INPUT,		"Input" 			},
-	{ VIRTIO_ID_VSOCK,		"VSOCK Transport" 		},
-	{ VIRTIO_ID_CRYPTO,		"Crypto" 			},
+	{ VIRTIO_ID_INPUT,		"Input"				},
+	{ VIRTIO_ID_VSOCK,		"VSOCK Transport"		},
+	{ VIRTIO_ID_CRYPTO,		"Crypto"			},
+
 	{ 0, NULL }
 };
 
 /* Device independent features. */
 static struct virtio_feature_desc virtio_common_feature_desc[] = {
-	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"	},
-	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirect"	},
-	{ VIRTIO_RING_F_EVENT_IDX,	"EventIdx"	},
-	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"	},
+	{ VIRTIO_F_NOTIFY_ON_EMPTY,	"NotifyOnEmpty"		}, /* Legacy */
+	{ VIRTIO_F_ANY_LAYOUT,		"AnyLayout"		}, /* Legacy */
+	{ VIRTIO_RING_F_INDIRECT_DESC,	"RingIndirectDesc"	},
+	{ VIRTIO_RING_F_EVENT_IDX,	"RingEventIdx"		},
+	{ VIRTIO_F_BAD_FEATURE,		"BadFeature"		}, /* Legacy */
+	{ VIRTIO_F_VERSION_1,		"Version1"		},
+	{ VIRTIO_F_IOMMU_PLATFORM,	"IOMMUPlatform"		},
 
 	{ 0, NULL }
 };
@@ -125,12 +129,13 @@ virtio_describe(device_t dev, const char *msg,
 	const char *name;
 	int n;
 
-	if ((buf = malloc(512, M_TEMP, M_NOWAIT)) == NULL) {
-		device_printf(dev, "%s features: %#jx\n", msg, (uintmax_t) features);
+	if ((buf = malloc(1024, M_TEMP, M_NOWAIT)) == NULL) {
+		device_printf(dev, "%s features: %#jx\n",
+		    msg, (uintmax_t) features);
 		return;
 	}
 
-	sbuf_new(&sb, buf, 512, SBUF_FIXEDLEN);
+	sbuf_new(&sb, buf, 1024, SBUF_FIXEDLEN);
 	sbuf_printf(&sb, "%s features: %#jx", msg, (uintmax_t) features);
 
 	for (n = 0, val = 1ULL << 63; val != 0; val >>= 1) {
@@ -163,6 +168,48 @@ virtio_describe(device_t dev, const char *msg,
 	free(buf, M_TEMP);
 }
 
+uint64_t
+virtio_filter_transport_features(uint64_t features)
+{
+	uint64_t transport, mask;
+
+	transport = (1ULL <<
+	    (VIRTIO_TRANSPORT_F_END - VIRTIO_TRANSPORT_F_START)) - 1;
+	transport <<= VIRTIO_TRANSPORT_F_START;
+
+	mask = -1ULL & ~transport;
+	mask |= VIRTIO_RING_F_INDIRECT_DESC;
+	mask |= VIRTIO_RING_F_EVENT_IDX;
+	mask |= VIRTIO_F_VERSION_1;
+
+	return (features & mask);
+}
+
+int
+virtio_bus_is_modern(device_t dev)
+{
+	uintptr_t modern;
+
+	virtio_read_ivar(dev, VIRTIO_IVAR_MODERN, &modern);
+	return (modern != 0);
+}
+
+void
+virtio_read_device_config_array(device_t dev, bus_size_t offset, void *dst,
+    int size, int count)
+{
+	int i, gen;
+
+	do {
+		gen = virtio_config_generation(dev);
+
+		for (i = 0; i < count; i++) {
+			virtio_read_device_config(dev, offset + i * size,
+			    (uint8_t *) dst + i * size, size);
+		}
+	} while (gen != virtio_config_generation(dev));
+}
+
 /*
  * VirtIO bus method wrappers.
  */
@@ -191,6 +238,13 @@ virtio_negotiate_features(device_t dev, uint64_t child_features)
 }
 
 int
+virtio_finalize_features(device_t dev)
+{
+
+	return (VIRTIO_BUS_FINALIZE_FEATURES(device_get_parent(dev)));
+}
+
+int
 virtio_alloc_virtqueues(device_t dev, int flags, int nvqs,
     struct vq_alloc_info *info)
 {