xref: /openbsd-src/sys/dev/pv/virtiovar.h (revision 1f33ff36f52757e5d185802ef3806193b3e41cfa)
1 /*	$OpenBSD: virtiovar.h,v 1.29 2025/01/29 14:03:19 sf Exp $	*/
2 /*	$NetBSD: virtiovar.h,v 1.1 2011/10/30 12:12:21 hannken Exp $	*/
3 
4 /*
5  * Copyright (c) 2012 Stefan Fritsch.
6  * Copyright (c) 2010 Minoura Makoto.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * Part of the file derived from `Virtio PCI Card Specification v0.8.6 DRAFT'
32  * Appendix A.
33  */
34 /* An interface for efficient virtio implementation.
35  *
36  * This header is BSD licensed so anyone can use the definitions
37  * to implement compatible drivers/servers.
38  *
39  * Copyright 2007, 2009, IBM Corporation
40  * All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of IBM nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  */
65 
66 
67 #ifndef _DEV_PV_VIRTIOVAR_H_
68 #define	_DEV_PV_VIRTIOVAR_H_
69 
70 #include <sys/param.h>
71 #include <sys/queue.h>
72 #include <sys/device.h>
73 #include <sys/mutex.h>
74 #include <machine/bus.h>
75 
76 #include <dev/pv/virtioreg.h>
77 
78 #ifndef VIRTIO_DEBUG
79 #define VIRTIO_DEBUG		0
80 #endif
81 
82 /* flags for config(8) */
83 #define VIRTIO_CF_NO_INDIRECT		1
84 #define VIRTIO_CF_NO_EVENT_IDX		2
85 #define VIRTIO_CF_PREFER_VERSION_09	8
86 
87 struct virtio_attach_args {
88 	int			 va_devid;	/* virtio device id */
89 	unsigned int		 va_nintr;	/* number of intr vectors */
90 };
91 
92 struct vq_entry {
93 	SLIST_ENTRY(vq_entry)	 qe_list;	/* free list */
94 	uint16_t		 qe_index;	/* index in vq_desc array */
95 
96 	/* The following are used only in the `head' entry */
97 	int16_t			 qe_next;	/* next enq slot */
98 	int16_t			 qe_indirect;	/* 1 if using indirect */
99 	int16_t			 qe_vr_index;	/* index in sc_reqs array */
100 	struct vring_desc	*qe_desc_base;	/* pointer to vd array */
101 };
102 
103 struct virtqueue {
104 	struct virtio_softc	*vq_owner;
105 	unsigned int		vq_num;  /* queue size (# of entries),
106 					  * 0 if unused/non-existant */
107 	unsigned int		vq_mask; /* (1 << vq_num - 1) */
108 	int			vq_index; /* queue number (0, 1, ...) */
109 
110 	/* vring pointers (KVA) */
111 	struct vring_desc	*vq_desc;
112 	struct vring_avail	*vq_avail;
113 	struct vring_used	*vq_used;
114 	void			*vq_indirect;
115 
116 	/* virtqueue allocation info */
117 	void			*vq_vaddr;
118 	int			vq_availoffset;
119 	int			vq_usedoffset;
120 	int			vq_indirectoffset;
121 	bus_dma_segment_t	vq_segs[1];
122 	unsigned int		vq_bytesize;
123 	bus_dmamap_t		vq_dmamap;
124 
125 	int			vq_maxnsegs;
126 
127 	/* free entry management */
128 	struct vq_entry		*vq_entries;
129 	SLIST_HEAD(, vq_entry) vq_freelist;
130 
131 	/* enqueue/dequeue status */
132 	uint16_t		vq_avail_idx;
133 	uint16_t		vq_used_idx;
134 	int			vq_queued;
135 
136 	/* interrupt handler */
137 	int			(*vq_done)(struct virtqueue*);
138 	/* 1.x only: offset for notify address calculation */
139 	uint32_t		vq_notify_off;
140 	int			vq_intr_vec;
141 };
142 
143 struct virtio_feature_name {
144 	uint64_t	 bit;
145 	const char	*name;
146 };
147 
148 struct virtio_ops {
149 	void		(*kick)(struct virtio_softc *, uint16_t);
150 	uint8_t		(*read_dev_cfg_1)(struct virtio_softc *, int);
151 	uint16_t	(*read_dev_cfg_2)(struct virtio_softc *, int);
152 	uint32_t	(*read_dev_cfg_4)(struct virtio_softc *, int);
153 	uint64_t	(*read_dev_cfg_8)(struct virtio_softc *, int);
154 	void		(*write_dev_cfg_1)(struct virtio_softc *, int, uint8_t);
155 	void		(*write_dev_cfg_2)(struct virtio_softc *, int, uint16_t);
156 	void		(*write_dev_cfg_4)(struct virtio_softc *, int, uint32_t);
157 	void		(*write_dev_cfg_8)(struct virtio_softc *, int, uint64_t);
158 	uint16_t	(*read_queue_size)(struct virtio_softc *, uint16_t);
159 	void		(*setup_queue)(struct virtio_softc *, struct virtqueue *, uint64_t);
160 	void		(*setup_intrs)(struct virtio_softc *);
161 	int		(*get_status)(struct virtio_softc *);
162 	void		(*set_status)(struct virtio_softc *, int);
163 	int		(*neg_features)(struct virtio_softc *, const struct virtio_feature_name *);
164 	int		(*attach_finish)(struct virtio_softc *, struct virtio_attach_args *);
165 	int		(*poll_intr)(void *);
166 	void		(*intr_barrier)(struct virtio_softc *);
167 	int		(*intr_establish)(struct virtio_softc *, struct virtio_attach_args *,
168 			    int, struct cpu_info *, int (*)(void *), void *);
169 };
170 
171 #define VIRTIO_CHILD_ERROR	((void*)1)
172 
173 struct virtio_softc {
174 	struct device		 sc_dev;
175 	bus_dma_tag_t		 sc_dmat;	/* set by transport */
176 	const struct virtio_ops	*sc_ops;	/* set by transport */
177 
178 	int			 sc_ipl;		/* set by child */
179 
180 	uint64_t		 sc_driver_features;
181 	uint64_t		 sc_active_features;
182 	int			 sc_indirect;
183 	int			 sc_version_1;
184 
185 	int			 sc_nvqs;	/* size of sc_vqs, set by child */
186 	struct virtqueue	*sc_vqs;	/* set by child */
187 
188 	struct device		*sc_child;	/* set by child,
189 						 * VIRTIO_CHILD_ERROR on error
190 						 */
191 	int			(*sc_config_change)(struct virtio_softc*);
192 						/* set by child */
193 };
194 
195 /* public interface */
196 #define	virtio_read_device_config_1(sc, o)	(sc)->sc_ops->read_dev_cfg_1(sc, o)
197 #define	virtio_read_device_config_2(sc, o)	(sc)->sc_ops->read_dev_cfg_2(sc, o)
198 #define	virtio_read_device_config_4(sc, o)	(sc)->sc_ops->read_dev_cfg_4(sc, o)
199 #define	virtio_read_device_config_8(sc, o)	(sc)->sc_ops->read_dev_cfg_8(sc, o)
200 #define	virtio_write_device_config_1(sc, o, v)	(sc)->sc_ops->write_dev_cfg_1(sc, o, v)
201 #define	virtio_write_device_config_2(sc, o, v)	(sc)->sc_ops->write_dev_cfg_2(sc, o, v)
202 #define	virtio_write_device_config_4(sc, o, v)	(sc)->sc_ops->write_dev_cfg_4(sc, o, v)
203 #define	virtio_write_device_config_8(sc, o, v)	(sc)->sc_ops->write_dev_cfg_8(sc, o, v)
204 #define	virtio_read_queue_size(sc, i)		(sc)->sc_ops->read_queue_size(sc, i)
205 #define	virtio_setup_queue(sc, i, v)		(sc)->sc_ops->setup_queue(sc, i, v)
206 #define	virtio_negotiate_features(sc, n)	(sc)->sc_ops->neg_features(sc, n)
207 #define	virtio_poll_intr(sc)			(sc)->sc_ops->poll_intr(sc)
208 #define	virtio_get_status(sc)			(sc)->sc_ops->get_status(sc)
209 #define	virtio_set_status(sc, i)		(sc)->sc_ops->set_status(sc, i)
210 #define	virtio_intr_barrier(sc)			(sc)->sc_ops->intr_barrier(sc)
211 
212 /*
213  * virtio_intr_establish() only works if va_nintr > 1. If it is called by a
214  * child driver, the transport driver will skip automatic intr allocation and
215  * the child driver must allocate all required interrupts itself. Vector 0 is
216  * always used for the config change interrupt.
217  */
218 #define	virtio_intr_establish(sc, va, v, ci, fn, a)	(sc)->sc_ops->intr_establish(sc, va, v, ci, fn, a)
219 
220 /* only for transport drivers */
221 #define	virtio_device_reset(sc)			virtio_set_status((sc), 0)
222 
223 static inline int
224 virtio_has_feature(struct virtio_softc *sc, uint64_t fbit)
225 {
226 	if (sc->sc_active_features & fbit)
227 		return 1;
228 	return 0;
229 }
230 
231 int virtio_alloc_vq(struct virtio_softc*, struct virtqueue*, int, int,
232 		    const char*);
233 int virtio_free_vq(struct virtio_softc*, struct virtqueue*);
234 int virtio_attach_finish(struct virtio_softc *, struct virtio_attach_args *);
235 void virtio_reset(struct virtio_softc *);
236 void virtio_reinit_start(struct virtio_softc *);
237 void virtio_reinit_end(struct virtio_softc *);
238 
239 int virtio_enqueue_prep(struct virtqueue*, int*);
240 int virtio_enqueue_reserve(struct virtqueue*, int, int);
241 int virtio_enqueue(struct virtqueue*, int, bus_dmamap_t, int);
242 int virtio_enqueue_p(struct virtqueue*, int, bus_dmamap_t, bus_addr_t,
243 		     bus_size_t, int);
244 void virtio_enqueue_commit(struct virtio_softc*, struct virtqueue*, int, int);
245 #define		virtio_notify(sc,vq)	virtio_enqueue_commit(sc, vq, -1, 1)
246 
247 int virtio_enqueue_abort(struct virtqueue*, int);
248 void virtio_enqueue_trim(struct virtqueue*, int, int);
249 
250 int virtio_dequeue(struct virtio_softc*, struct virtqueue*, int *, int *);
251 int virtio_dequeue_commit(struct virtqueue*, int);
252 
253 int virtio_check_vqs(struct virtio_softc *);
254 int virtio_check_vq(struct virtio_softc *, struct virtqueue *);
255 void virtio_stop_vq_intr(struct virtio_softc *, struct virtqueue *);
256 int virtio_start_vq_intr(struct virtio_softc *, struct virtqueue *);
257 
258 const char *virtio_device_string(int);
259 #if VIRTIO_DEBUG
260 void virtio_log_features(uint64_t, uint64_t, const struct virtio_feature_name *);
261 void virtio_vq_dump(struct virtqueue *vq);
262 #endif
263 int virtio_nused(struct virtqueue *vq);
264 int virtio_postpone_intr(struct virtqueue *vq, uint16_t nslots);
265 int virtio_postpone_intr_smart(struct virtqueue *vq);
266 int virtio_postpone_intr_far(struct virtqueue *vq);
267 
268 #endif /* _DEV_PV_VIRTIOVAR_H_ */
269