xref: /openbsd/sys/dev/pci/virtio_pcireg.h (revision d8499287)
1 /*
2  * Copyright (c) 2019 Stefan Fritsch <sf@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #ifndef _DEV_PCI_VIRTIO_PCIREG_H_
18 #define _DEV_PCI_VIRTIO_PCIREG_H_
19 
20 /* Virtio 0.9 config space */
21 #define VIRTIO_CONFIG_DEVICE_FEATURES		0 /* 32bit */
22 #define VIRTIO_CONFIG_GUEST_FEATURES		4 /* 32bit */
23 #define VIRTIO_CONFIG_QUEUE_ADDRESS		8 /* 32bit */
24 #define VIRTIO_CONFIG_QUEUE_SIZE		12 /* 16bit */
25 #define VIRTIO_CONFIG_QUEUE_SELECT		14 /* 16bit */
26 #define VIRTIO_CONFIG_QUEUE_NOTIFY		16 /* 16bit */
27 #define VIRTIO_CONFIG_DEVICE_STATUS		18 /* 8bit */
28 #define VIRTIO_CONFIG_ISR_STATUS		19 /* 8bit */
29 #define  VIRTIO_CONFIG_ISR_CONFIG_CHANGE	2
30 #define VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI	20
31 /* Only if MSIX is enabled: */
32 #define VIRTIO_MSI_CONFIG_VECTOR		20 /* 16bit, optional */
33 #define VIRTIO_MSI_QUEUE_VECTOR			22 /* 16bit, optional */
34 #define VIRTIO_CONFIG_DEVICE_CONFIG_MSI		24
35 
36 #define VIRTIO_MSI_NO_VECTOR			0xffff
37 
38 /*
39  * Virtio 1.0 specific
40  */
41 
42 struct virtio_pci_cap {
43 	uint8_t cap_vndr;	/* Generic PCI field: PCI_CAP_ID_VNDR */
44 	uint8_t cap_next;	/* Generic PCI field: next ptr. */
45 	uint8_t cap_len;	/* Generic PCI field: capability length */
46 	uint8_t cfg_type;	/* Identifies the structure. */
47 	uint8_t bar;		/* Where to find it. */
48 	uint8_t padding[3];	/* Pad to full dword. */
49 	uint32_t offset;	/* Offset within bar. */
50 	uint32_t length;	/* Length of the structure, in bytes. */
51 } __packed;
52 
53 /* Common configuration */
54 #define VIRTIO_PCI_CAP_COMMON_CFG	1
55 /* Notifications */
56 #define VIRTIO_PCI_CAP_NOTIFY_CFG	2
57 /* ISR Status */
58 #define VIRTIO_PCI_CAP_ISR_CFG		3
59 /* Device specific configuration */
60 #define VIRTIO_PCI_CAP_DEVICE_CFG	4
61 /* PCI configuration access */
62 #define VIRTIO_PCI_CAP_PCI_CFG		5
63 
64 struct virtio_pci_notify_cap {
65 	struct virtio_pci_cap cap;
66 	uint32_t notify_off_multiplier;	/* Multiplier for queue_notify_off. */
67 } __packed;
68 
69 struct virtio_pci_cfg_cap {
70 	struct virtio_pci_cap cap;
71 	uint8_t pci_cfg_data[4];	/* Data for BAR access. */
72 } __packed;
73 
74 struct virtio_pci_common_cfg {
75 	/* About the whole device. */
76 	uint32_t device_feature_select;	/* read-write */
77 	uint32_t device_feature;	/* read-only for driver */
78 	uint32_t driver_feature_select;	/* read-write */
79 	uint32_t driver_feature;	/* read-write */
80 	uint16_t config_msix_vector;	/* read-write */
81 	uint16_t num_queues;		/* read-only for driver */
82 	uint8_t device_status;		/* read-write */
83 	uint8_t config_generation;	/* read-only for driver */
84 
85 	/* About a specific virtqueue. */
86 	uint16_t queue_select;		/* read-write */
87 	uint16_t queue_size;		/* read-write, power of 2, or 0. */
88 	uint16_t queue_msix_vector;	/* read-write */
89 	uint16_t queue_enable;		/* read-write */
90 	uint16_t queue_notify_off;	/* read-only for driver */
91 	uint64_t queue_desc;		/* read-write */
92 	uint64_t queue_avail;		/* read-write */
93 	uint64_t queue_used;		/* read-write */
94 } __packed;
95 
96 #endif /* _DEV_PCI_VIRTIO_PCIREG_H_ */
97