1/* $NetBSD: virtioreg.h,v 1.6 2015/10/29 01:56:12 christos Exp $ */
2
3/*
4 * Copyright (c) 2010 Minoura Makoto.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28/*
29 * Part of the file derived from `Virtio PCI Card Specification v0.8.6 DRAFT'
30 * Appendix A.
31 */
32/* An interface for efficient virtio implementation.
33 *
34 * This header is BSD licensed so anyone can use the definitions
35 * to implement compatible drivers/servers.
36 *
37 * Copyright 2007, 2009, IBM Corporation
38 * All rights reserved.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 3. Neither the name of IBM nor the names of its contributors
49 * may be used to endorse or promote products derived from this software
50 * without specific prior written permission.
51 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 */
63
64
65#ifndef _DEV_PCI_VIRTIOREG_H_
66#define _DEV_PCI_VIRTIOREG_H_
67
68#include <sys/types.h>
69
70/* Virtio product id (subsystem) */
71#define PCI_PRODUCT_VIRTIO_NETWORK 1
72#define PCI_PRODUCT_VIRTIO_BLOCK 2
73#define PCI_PRODUCT_VIRTIO_CONSOLE 3
74#define PCI_PRODUCT_VIRTIO_ENTROPY 4
75#define PCI_PRODUCT_VIRTIO_BALLOON 5
76#define PCI_PRODUCT_VIRTIO_IOMEM 6
77#define PCI_PRODUCT_VIRTIO_RPMSG 7
78#define PCI_PRODUCT_VIRTIO_SCSI 8
79#define PCI_PRODUCT_VIRTIO_9P 9
80#define PCI_PRODUCT_VIRTIO_MAC80211 10
81
82/* Virtio header */
83#define VIRTIO_CONFIG_DEVICE_FEATURES 0 /* 32bit */
84#define VIRTIO_CONFIG_GUEST_FEATURES 4 /* 32bit */
85#define VIRTIO_F_NOTIFY_ON_EMPTY (1<<24)
86#define VIRTIO_F_RING_INDIRECT_DESC (1<<28)
87#define VIRTIO_F_BAD_FEATURE (1<<30)
88#define VIRTIO_CONFIG_QUEUE_ADDRESS 8 /* 32bit */
89#define VIRTIO_CONFIG_QUEUE_SIZE 12 /* 16bit */
90#define VIRTIO_CONFIG_QUEUE_SELECT 14 /* 16bit */
91#define VIRTIO_CONFIG_QUEUE_NOTIFY 16 /* 16bit */
92#define VIRTIO_CONFIG_DEVICE_STATUS 18 /* 8bit */
93#define VIRTIO_CONFIG_DEVICE_STATUS_RESET 0
94#define VIRTIO_CONFIG_DEVICE_STATUS_ACK 1
95#define VIRTIO_CONFIG_DEVICE_STATUS_DRIVER 2
96#define VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK 4
97#define VIRTIO_CONFIG_DEVICE_STATUS_FAILED 128
98#define VIRTIO_CONFIG_ISR_STATUS 19 /* 8bit */
99#define VIRTIO_CONFIG_ISR_CONFIG_CHANGE 2
100#define VIRTIO_CONFIG_CONFIG_VECTOR 20 /* 16bit, optional */
101#define VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI 20
102#define VIRTIO_CONFIG_DEVICE_CONFIG_MSI 24
103/* MSI/MSI-X */
104#define VIRTIO_CONFIG_MSI_CONFIG_VECTOR 20
105#define VIRTIO_CONFIG_MSI_QUEUE_VECTOR 22
106
107#define VIRTIO_COMMON_FLAG_BITS \
108 "\20" \
109 "\x1f""BAD_FEATURE" \
110 "\x1e""EVENT_IDX" \
111 "\x1d""INDIRECT_DESC" \
112 "\x19""NOTIFY_ON_EMPTY"
113
114/* Virtqueue */
115/* This marks a buffer as continuing via the next field. */
116#define VRING_DESC_F_NEXT 1
117/* This marks a buffer as write-only (otherwise read-only). */
118#define VRING_DESC_F_WRITE 2
119/* This means the buffer contains a list of buffer descriptors. */
120#define VRING_DESC_F_INDIRECT 4
121
122/* The Host uses this in used->flags to advise the Guest: don't kick me
123 * when you add a buffer. It's unreliable, so it's simply an
124 * optimization. Guest will still kick if it's out of buffers. */
125#define VRING_USED_F_NO_NOTIFY 1
126/* The Guest uses this in avail->flags to advise the Host: don't
127 * interrupt me when you consume a buffer. It's unreliable, so it's
128 * simply an optimization. */
129#define VRING_AVAIL_F_NO_INTERRUPT 1
130
131/* Virtio ring descriptors: 16 bytes.
132 * These can chain together via "next". */
133struct vring_desc {
134 /* Address (guest-physical). */
135 uint64_t addr;
136 /* Length. */
137 uint32_t len;
138 /* The flags as indicated above. */
139 uint16_t flags;
140 /* We chain unused descriptors via this, too */
141 uint16_t next;
142} __packed;
143
144struct vring_avail {
145 uint16_t flags;
146 uint16_t idx;
147 uint16_t ring[0];
148} __packed;
149
150/* u32 is used here for ids for padding reasons. */
151struct vring_used_elem {
152 /* Index of start of used descriptor chain. */
153 uint32_t id;
154 /* Total length of the descriptor chain which was written to. */
155 uint32_t len;
156} __packed;
157
158struct vring_used {
159 uint16_t flags;
160 uint16_t idx;
161 struct vring_used_elem ring[0];
162} __packed;
163
164/* The standard layout for the ring is a continuous chunk of memory which
165 * looks like this. We assume num is a power of 2.
166 *
167 * struct vring {
168 * // The actual descriptors (16 bytes each)
169 * struct vring_desc desc[num];
170 *
171 * // A ring of available descriptor heads with free-running index.
172 * __u16 avail_flags;
173 * __u16 avail_idx;
174 * __u16 available[num];
175 *
176 * // Padding to the next align boundary.
177 * char pad[];
178 *
179 * // A ring of used descriptor heads with free-running index.
180 * __u16 used_flags;
181 * __u16 used_idx;
182 * struct vring_used_elem used[num];
183 * };
184 * Note: for virtio PCI, align is 4096.
185 */
186
187#define VIRTIO_PAGE_SIZE (4096)
188
189#endif /* _DEV_PCI_VIRTIOREG_H_ */
190