xref: /openbsd-src/sys/dev/fdt/virtio_mmio.c (revision d1df930ffab53da22f3324c32bed7ac5709915e6)
1 /*	$OpenBSD: virtio_mmio.c,v 1.3 2018/08/06 10:52:30 patrick Exp $	*/
2 /*	$NetBSD: virtio.c,v 1.3 2011/11/02 23:05:52 njoly Exp $	*/
3 
4 /*
5  * Copyright (c) 2014 Patrick Wildt <patrick@blueri.se>
6  * Copyright (c) 2012 Stefan Fritsch.
7  * Copyright (c) 2010 Minoura Makoto.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/device.h>
35 #include <sys/mutex.h>
36 
37 #include <dev/pv/virtioreg.h>
38 #include <dev/pv/virtiovar.h>
39 
40 #include <machine/fdt.h>
41 
42 #include <dev/ofw/fdt.h>
43 #include <dev/ofw/openfirm.h>
44 
45 #define VIRTIO_MMIO_MAGIC		('v' | 'i' << 8 | 'r' << 16 | 't' << 24)
46 
47 #define VIRTIO_MMIO_MAGIC_VALUE		0x000
48 #define VIRTIO_MMIO_VERSION		0x004
49 #define VIRTIO_MMIO_DEVICE_ID		0x008
50 #define VIRTIO_MMIO_VENDOR_ID		0x00c
51 #define VIRTIO_MMIO_HOST_FEATURES	0x010
52 #define VIRTIO_MMIO_HOST_FEATURES_SEL	0x014
53 #define VIRTIO_MMIO_GUEST_FEATURES	0x020
54 #define VIRTIO_MMIO_GUEST_FEATURES_SEL	0x024
55 #define VIRTIO_MMIO_GUEST_PAGE_SIZE	0x028
56 #define VIRTIO_MMIO_QUEUE_SEL		0x030
57 #define VIRTIO_MMIO_QUEUE_NUM_MAX	0x034
58 #define VIRTIO_MMIO_QUEUE_NUM		0x038
59 #define VIRTIO_MMIO_QUEUE_ALIGN		0x03c
60 #define VIRTIO_MMIO_QUEUE_PFN		0x040
61 #define VIRTIO_MMIO_QUEUE_NOTIFY	0x050
62 #define VIRTIO_MMIO_INTERRUPT_STATUS	0x060
63 #define VIRTIO_MMIO_INTERRUPT_ACK	0x064
64 #define VIRTIO_MMIO_STATUS		0x070
65 #define VIRTIO_MMIO_CONFIG		0x100
66 
67 #define VIRTIO_MMIO_INT_VRING		(1 << 0)
68 #define VIRTIO_MMIO_INT_CONFIG		(1 << 1)
69 
70 #define DEVNAME(sc) (sc)->sc_dev.dv_xname
71 
72 /*
73  * XXX: Before being used on big endian arches, the access to config registers
74  * XXX: needs to be reviewed/fixed. The non-device specific registers are
75  * XXX: PCI-endian while the device specific registers are native endian.
76  */
77 
78 #define virtio_set_status(sc, s) virtio_mmio_set_status(sc, s)
79 #define virtio_device_reset(sc) virtio_set_status((sc), 0)
80 
81 int		virtio_mmio_match(struct device *, void *, void *);
82 void		virtio_mmio_attach(struct device *, struct device *, void *);
83 int		virtio_mmio_detach(struct device *, int);
84 
85 void		virtio_mmio_kick(struct virtio_softc *, uint16_t);
86 uint8_t		virtio_mmio_read_device_config_1(struct virtio_softc *, int);
87 uint16_t	virtio_mmio_read_device_config_2(struct virtio_softc *, int);
88 uint32_t	virtio_mmio_read_device_config_4(struct virtio_softc *, int);
89 uint64_t	virtio_mmio_read_device_config_8(struct virtio_softc *, int);
90 void		virtio_mmio_write_device_config_1(struct virtio_softc *, int, uint8_t);
91 void		virtio_mmio_write_device_config_2(struct virtio_softc *, int, uint16_t);
92 void		virtio_mmio_write_device_config_4(struct virtio_softc *, int, uint32_t);
93 void		virtio_mmio_write_device_config_8(struct virtio_softc *, int, uint64_t);
94 uint16_t	virtio_mmio_read_queue_size(struct virtio_softc *, uint16_t);
95 void		virtio_mmio_setup_queue(struct virtio_softc *, uint16_t, uint32_t);
96 void		virtio_mmio_set_status(struct virtio_softc *, int);
97 uint32_t	virtio_mmio_negotiate_features(struct virtio_softc *, uint32_t,
98 					      const struct virtio_feature_name *);
99 int		virtio_mmio_intr(void *);
100 
101 struct virtio_mmio_softc {
102 	struct virtio_softc	sc_sc;
103 
104 	bus_space_tag_t		sc_iot;
105 	bus_space_handle_t	sc_ioh;
106 	bus_size_t		sc_iosize;
107 	bus_dma_tag_t		sc_dmat;
108 
109 	void			*sc_ih;
110 
111 	int			sc_config_offset;
112 };
113 
114 struct cfattach virtio_mmio_ca = {
115 	sizeof(struct virtio_mmio_softc),
116 	virtio_mmio_match,
117 	virtio_mmio_attach,
118 	virtio_mmio_detach,
119 	NULL
120 };
121 
122 struct cfattach virtio_mmio_fdt_ca = {
123 	sizeof(struct virtio_mmio_softc),
124 	NULL,
125 	virtio_mmio_attach,
126 	virtio_mmio_detach,
127 	NULL
128 };
129 
130 struct virtio_ops virtio_mmio_ops = {
131 	virtio_mmio_kick,
132 	virtio_mmio_read_device_config_1,
133 	virtio_mmio_read_device_config_2,
134 	virtio_mmio_read_device_config_4,
135 	virtio_mmio_read_device_config_8,
136 	virtio_mmio_write_device_config_1,
137 	virtio_mmio_write_device_config_2,
138 	virtio_mmio_write_device_config_4,
139 	virtio_mmio_write_device_config_8,
140 	virtio_mmio_read_queue_size,
141 	virtio_mmio_setup_queue,
142 	virtio_mmio_set_status,
143 	virtio_mmio_negotiate_features,
144 	virtio_mmio_intr,
145 };
146 
147 uint16_t
148 virtio_mmio_read_queue_size(struct virtio_softc *vsc, uint16_t idx)
149 {
150 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
151 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_SEL, idx);
152 	return bus_space_read_4(sc->sc_iot, sc->sc_ioh,
153 	    VIRTIO_MMIO_QUEUE_NUM_MAX);
154 }
155 
156 void
157 virtio_mmio_setup_queue(struct virtio_softc *vsc, uint16_t idx, uint32_t addr)
158 {
159 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
160 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_SEL, idx);
161 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_NUM,
162 	    bus_space_read_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_NUM_MAX));
163 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_ALIGN,
164 	    PAGE_SIZE);
165 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_PFN, addr);
166 }
167 
168 void
169 virtio_mmio_set_status(struct virtio_softc *vsc, int status)
170 {
171 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
172 	int old = 0;
173 
174 	if (status != 0)
175 		old = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
176 				       VIRTIO_MMIO_STATUS);
177 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_STATUS,
178 			  status|old);
179 }
180 
181 int
182 virtio_mmio_match(struct device *parent, void *cfdata, void *aux)
183 {
184 	struct fdt_attach_args *faa = aux;
185 
186 	return OF_is_compatible(faa->fa_node, "virtio,mmio");
187 }
188 
189 void
190 virtio_mmio_attach(struct device *parent, struct device *self, void *aux)
191 {
192 	struct fdt_attach_args *faa = aux;
193 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)self;
194 	struct virtio_softc *vsc = &sc->sc_sc;
195 	uint32_t id, magic, version;
196 
197 	if (faa->fa_nreg < 1) {
198 		printf(": no register data\n");
199 		return;
200 	}
201 
202 	sc->sc_iosize = faa->fa_reg[0].size;
203 	sc->sc_iot = faa->fa_iot;
204 	sc->sc_dmat = faa->fa_dmat;
205 	if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr, faa->fa_reg[0].size,
206 	    0, &sc->sc_ioh))
207 		panic("%s: bus_space_map failed!", __func__);
208 
209 	magic = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
210 	    VIRTIO_MMIO_MAGIC_VALUE);
211 	if (magic != VIRTIO_MMIO_MAGIC) {
212 		printf(": wrong magic value 0x%08x; giving up\n", magic);
213 		return;
214 	}
215 
216 	version = bus_space_read_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_VERSION);
217 	if (version != 1) {
218 		printf(": unknown version 0x%02x; giving up\n", version);
219 		return;
220 	}
221 
222 	id = bus_space_read_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_DEVICE_ID);
223 	printf(": Virtio %s Device", virtio_device_string(id));
224 
225 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_GUEST_PAGE_SIZE,
226 	    PAGE_SIZE);
227 
228 	printf("\n");
229 
230 	/* No device connected. */
231 	if (id == 0)
232 		return;
233 
234 	vsc->sc_ops = &virtio_mmio_ops;
235 	vsc->sc_dmat = sc->sc_dmat;
236 	sc->sc_config_offset = VIRTIO_MMIO_CONFIG;
237 
238 	virtio_device_reset(vsc);
239 	virtio_mmio_set_status(vsc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
240 	virtio_mmio_set_status(vsc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
241 
242 	/* XXX: use softc as aux... */
243 	vsc->sc_childdevid = id;
244 	vsc->sc_child = NULL;
245 	config_found(self, sc, NULL);
246 	if (vsc->sc_child == NULL) {
247 		printf("%s: no matching child driver; not configured\n",
248 		    vsc->sc_dev.dv_xname);
249 		goto fail_1;
250 	}
251 	if (vsc->sc_child == VIRTIO_CHILD_ERROR) {
252 		printf("%s: virtio configuration failed\n",
253 		    vsc->sc_dev.dv_xname);
254 		goto fail_1;
255 	}
256 
257 	sc->sc_ih = fdt_intr_establish(faa->fa_node, vsc->sc_ipl,
258 	    virtio_mmio_intr, sc, vsc->sc_dev.dv_xname);
259 	if (sc->sc_ih == NULL) {
260 		printf("%s: couldn't establish interrupt\n",
261 		    vsc->sc_dev.dv_xname);
262 		goto fail_2;
263 	}
264 
265 	virtio_set_status(vsc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK);
266 	return;
267 
268 fail_2:
269 	config_detach(vsc->sc_child, 0);
270 fail_1:
271 	/* no mmio_mapreg_unmap() or mmio_intr_unmap() */
272 	virtio_set_status(vsc, VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
273 }
274 
275 int
276 virtio_mmio_detach(struct device *self, int flags)
277 {
278 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)self;
279 	struct virtio_softc *vsc = &sc->sc_sc;
280 	int r;
281 
282 	if (vsc->sc_child != 0 && vsc->sc_child != VIRTIO_CHILD_ERROR) {
283 		r = config_detach(vsc->sc_child, flags);
284 		if (r)
285 			return r;
286 	}
287 	KASSERT(vsc->sc_child == 0 || vsc->sc_child == VIRTIO_CHILD_ERROR);
288 	KASSERT(vsc->sc_vqs == 0);
289 	fdt_intr_disestablish(sc->sc_ih);
290 	sc->sc_ih = 0;
291 	if (sc->sc_iosize)
292 		bus_space_unmap(sc->sc_iot, sc->sc_ioh, sc->sc_iosize);
293 	sc->sc_iosize = 0;
294 
295 	return 0;
296 }
297 
298 /*
299  * Feature negotiation.
300  * Prints available / negotiated features if guest_feature_names != NULL and
301  * VIRTIO_DEBUG is 1
302  */
303 uint32_t
304 virtio_mmio_negotiate_features(struct virtio_softc *vsc, uint32_t guest_features,
305 			  const struct virtio_feature_name *guest_feature_names)
306 {
307 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
308 	uint32_t host, neg;
309 
310 	/*
311 	 * indirect descriptors can be switched off by setting bit 1 in the
312 	 * driver flags, see config(8)
313 	 */
314 	if (!(vsc->sc_dev.dv_cfdata->cf_flags & 1) &&
315 	    !(vsc->sc_child->dv_cfdata->cf_flags & 1)) {
316 		guest_features |= VIRTIO_F_RING_INDIRECT_DESC;
317 	} else {
318 		printf("RingIndirectDesc disabled by UKC\n");
319 	}
320 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
321 	    VIRTIO_MMIO_HOST_FEATURES_SEL, 0);
322 	host = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
323 				VIRTIO_MMIO_HOST_FEATURES);
324 	neg = host & guest_features;
325 #if VIRTIO_DEBUG
326 	if (guest_feature_names)
327 		virtio_log_features(host, neg, guest_feature_names);
328 #endif
329 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
330 	    VIRTIO_MMIO_GUEST_FEATURES_SEL, 0);
331 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
332 			  VIRTIO_MMIO_GUEST_FEATURES, neg);
333 	vsc->sc_features = neg;
334 	if (neg & VIRTIO_F_RING_INDIRECT_DESC)
335 		vsc->sc_indirect = 1;
336 	else
337 		vsc->sc_indirect = 0;
338 
339 	return neg;
340 }
341 
342 /*
343  * Device configuration registers.
344  */
345 uint8_t
346 virtio_mmio_read_device_config_1(struct virtio_softc *vsc, int index)
347 {
348 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
349 	return bus_space_read_1(sc->sc_iot, sc->sc_ioh,
350 				sc->sc_config_offset + index);
351 }
352 
353 uint16_t
354 virtio_mmio_read_device_config_2(struct virtio_softc *vsc, int index)
355 {
356 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
357 	return bus_space_read_2(sc->sc_iot, sc->sc_ioh,
358 				sc->sc_config_offset + index);
359 }
360 
361 uint32_t
362 virtio_mmio_read_device_config_4(struct virtio_softc *vsc, int index)
363 {
364 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
365 	return bus_space_read_4(sc->sc_iot, sc->sc_ioh,
366 				sc->sc_config_offset + index);
367 }
368 
369 uint64_t
370 virtio_mmio_read_device_config_8(struct virtio_softc *vsc, int index)
371 {
372 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
373 	uint64_t r;
374 
375 	r = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
376 			     sc->sc_config_offset + index + sizeof(uint32_t));
377 	r <<= 32;
378 	r += bus_space_read_4(sc->sc_iot, sc->sc_ioh,
379 			      sc->sc_config_offset + index);
380 	return r;
381 }
382 
383 void
384 virtio_mmio_write_device_config_1(struct virtio_softc *vsc,
385 			     int index, uint8_t value)
386 {
387 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
388 	bus_space_write_1(sc->sc_iot, sc->sc_ioh,
389 			  sc->sc_config_offset + index, value);
390 }
391 
392 void
393 virtio_mmio_write_device_config_2(struct virtio_softc *vsc,
394 			     int index, uint16_t value)
395 {
396 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
397 	bus_space_write_2(sc->sc_iot, sc->sc_ioh,
398 			  sc->sc_config_offset + index, value);
399 }
400 
401 void
402 virtio_mmio_write_device_config_4(struct virtio_softc *vsc,
403 			     int index, uint32_t value)
404 {
405 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
406 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
407 			  sc->sc_config_offset + index, value);
408 }
409 
410 void
411 virtio_mmio_write_device_config_8(struct virtio_softc *vsc,
412 			     int index, uint64_t value)
413 {
414 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
415 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
416 			  sc->sc_config_offset + index,
417 			  value & 0xffffffff);
418 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
419 			  sc->sc_config_offset + index + sizeof(uint32_t),
420 			  value >> 32);
421 }
422 
423 /*
424  * Interrupt handler.
425  */
426 int
427 virtio_mmio_intr(void *arg)
428 {
429 	struct virtio_mmio_softc *sc = arg;
430 	struct virtio_softc *vsc = &sc->sc_sc;
431 	int isr, r = 0;
432 
433 	/* check and ack the interrupt */
434 	isr = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
435 			       VIRTIO_MMIO_INTERRUPT_STATUS);
436 	bus_space_write_4(sc->sc_iot, sc->sc_ioh,
437 			  VIRTIO_MMIO_INTERRUPT_ACK, isr);
438 	if ((isr & VIRTIO_MMIO_INT_CONFIG) &&
439 	    (vsc->sc_config_change != NULL))
440 		r = (vsc->sc_config_change)(vsc);
441 	if ((isr & VIRTIO_MMIO_INT_VRING))
442 		r |= virtio_check_vqs(vsc);
443 
444 	return r;
445 }
446 
447 void
448 virtio_mmio_kick(struct virtio_softc *vsc, uint16_t idx)
449 {
450 	struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
451 	bus_space_write_4(sc->sc_iot, sc->sc_ioh, VIRTIO_MMIO_QUEUE_NOTIFY,
452 	    idx);
453 }
454