xref: /freebsd/sys/dev/virtio/virtio_config.h (revision 09d986419d8834aa4fdb998695a8b7cce7e8e52a)
1 /*-
2  * This header is BSD licensed so anyone can use the definitions to implement
3  * compatible drivers/servers.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of IBM nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #ifndef _VIRTIO_CONFIG_H_
32 #define _VIRTIO_CONFIG_H_
33 
34 /* Status byte for guest to report progress. */
35 #define VIRTIO_CONFIG_STATUS_RESET	0x00
36 #define VIRTIO_CONFIG_STATUS_ACK	0x01
37 #define VIRTIO_CONFIG_STATUS_DRIVER	0x03
38 #define VIRTIO_CONFIG_STATUS_DRIVER_OK	0x04
39 #define VIRTIO_CONFIG_STATUS_FAILED	0x80
40 
41 /*
42  * Generate interrupt when the virtqueue ring is
43  * completely used, even if we've suppressed them.
44  */
45 #define VIRTIO_F_NOTIFY_ON_EMPTY (1 << 24)
46 
47 /* Support for indirect buffer descriptors. */
48 #define VIRTIO_RING_F_INDIRECT_DESC	(1 << 28)
49 
50 /* Support to suppress interrupt until specific index is reached. */
51 #define VIRTIO_RING_F_EVENT_IDX		(1 << 29)
52 
53 /*
54  * The guest should never negotiate this feature; it
55  * is used to detect faulty drivers.
56  */
57 #define VIRTIO_F_BAD_FEATURE (1 << 30)
58 
59 /*
60  * Some VirtIO feature bits (currently bits 28 through 31) are
61  * reserved for the transport being used (eg. virtio_ring), the
62  * rest are per-device feature bits.
63  */
64 #define VIRTIO_TRANSPORT_F_START	28
65 #define VIRTIO_TRANSPORT_F_END		32
66 
67 #endif /* _VIRTIO_CONFIG_H_ */
68