Commit | Line | Data |
---|---|---|
ac8954a4 OBC |
1 | /* |
2 | * Remote processor messaging transport (OMAP platform-specific bits) | |
3 | * | |
4 | * Copyright (C) 2011 Texas Instruments, Inc. | |
5 | * Copyright (C) 2011 Google, Inc. | |
6 | * | |
7 | * Ohad Ben-Cohen <ohad@wizery.com> | |
8 | * Brian Swetland <swetland@google.com> | |
9 | * | |
10 | * This software is licensed under the terms of the GNU General Public | |
11 | * License version 2, as published by the Free Software Foundation, and | |
12 | * may be copied, distributed, and modified under those terms. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | */ | |
19 | ||
20 | #include <linux/export.h> | |
21 | #include <linux/remoteproc.h> | |
ac8954a4 OBC |
22 | #include <linux/virtio.h> |
23 | #include <linux/virtio_config.h> | |
24 | #include <linux/virtio_ids.h> | |
25 | #include <linux/virtio_ring.h> | |
26 | #include <linux/err.h> | |
27 | #include <linux/kref.h> | |
28 | #include <linux/slab.h> | |
29 | ||
30 | #include "remoteproc_internal.h" | |
31 | ||
ac8954a4 OBC |
32 | /* kick the remote processor, and let it know which virtqueue to poke at */ |
33 | static void rproc_virtio_notify(struct virtqueue *vq) | |
34 | { | |
7a186941 OBC |
35 | struct rproc_vring *rvring = vq->priv; |
36 | struct rproc *rproc = rvring->rvdev->rproc; | |
37 | int notifyid = rvring->notifyid; | |
ac8954a4 | 38 | |
b5ab5e24 | 39 | dev_dbg(&rproc->dev, "kicking vq index: %d\n", notifyid); |
ac8954a4 | 40 | |
7a186941 | 41 | rproc->ops->kick(rproc, notifyid); |
ac8954a4 OBC |
42 | } |
43 | ||
44 | /** | |
45 | * rproc_vq_interrupt() - tell remoteproc that a virtqueue is interrupted | |
46 | * @rproc: handle to the remote processor | |
7a186941 | 47 | * @notifyid: index of the signalled virtqueue (unique per this @rproc) |
ac8954a4 OBC |
48 | * |
49 | * This function should be called by the platform-specific rproc driver, | |
50 | * when the remote processor signals that a specific virtqueue has pending | |
51 | * messages available. | |
52 | * | |
7a186941 | 53 | * Returns IRQ_NONE if no message was found in the @notifyid virtqueue, |
ac8954a4 OBC |
54 | * and otherwise returns IRQ_HANDLED. |
55 | */ | |
7a186941 | 56 | irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int notifyid) |
ac8954a4 | 57 | { |
7a186941 OBC |
58 | struct rproc_vring *rvring; |
59 | ||
b5ab5e24 | 60 | dev_dbg(&rproc->dev, "vq index %d is interrupted\n", notifyid); |
7a186941 OBC |
61 | |
62 | rvring = idr_find(&rproc->notifyids, notifyid); | |
63 | if (!rvring || !rvring->vq) | |
64 | return IRQ_NONE; | |
65 | ||
66 | return vring_interrupt(0, rvring->vq); | |
ac8954a4 OBC |
67 | } |
68 | EXPORT_SYMBOL(rproc_vq_interrupt); | |
69 | ||
70 | static struct virtqueue *rp_find_vq(struct virtio_device *vdev, | |
71 | unsigned id, | |
72 | void (*callback)(struct virtqueue *vq), | |
73 | const char *name) | |
74 | { | |
7a186941 | 75 | struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); |
ac8954a4 | 76 | struct rproc *rproc = vdev_to_rproc(vdev); |
b5ab5e24 | 77 | struct device *dev = &rproc->dev; |
7a186941 | 78 | struct rproc_vring *rvring; |
ac8954a4 OBC |
79 | struct virtqueue *vq; |
80 | void *addr; | |
6db20ea8 | 81 | int len, size, ret; |
ac8954a4 | 82 | |
7a186941 OBC |
83 | /* we're temporarily limited to two virtqueues per rvdev */ |
84 | if (id >= ARRAY_SIZE(rvdev->vring)) | |
85 | return ERR_PTR(-EINVAL); | |
86 | ||
6db20ea8 OBC |
87 | ret = rproc_alloc_vring(rvdev, id); |
88 | if (ret) | |
89 | return ERR_PTR(ret); | |
ac8954a4 | 90 | |
6db20ea8 | 91 | rvring = &rvdev->vring[id]; |
7a186941 OBC |
92 | addr = rvring->va; |
93 | len = rvring->len; | |
ac8954a4 | 94 | |
7a186941 OBC |
95 | /* zero vring */ |
96 | size = vring_size(len, rvring->align); | |
97 | memset(addr, 0, size); | |
ac8954a4 | 98 | |
b5ab5e24 | 99 | dev_dbg(dev, "vring%d: va %p qsz %d notifyid %d\n", |
7a186941 | 100 | id, addr, len, rvring->notifyid); |
ac8954a4 | 101 | |
dd6da1c5 OBC |
102 | /* |
103 | * Create the new vq, and tell virtio we're not interested in | |
104 | * the 'weak' smp barriers, since we're talking with a real device. | |
105 | */ | |
63140e0e | 106 | vq = vring_new_virtqueue(len, rvring->align, vdev, false, addr, |
ac8954a4 OBC |
107 | rproc_virtio_notify, callback, name); |
108 | if (!vq) { | |
b5ab5e24 | 109 | dev_err(dev, "vring_new_virtqueue %s failed\n", name); |
6db20ea8 | 110 | rproc_free_vring(rvring); |
7a186941 | 111 | return ERR_PTR(-ENOMEM); |
ac8954a4 OBC |
112 | } |
113 | ||
7a186941 OBC |
114 | rvring->vq = vq; |
115 | vq->priv = rvring; | |
ac8954a4 OBC |
116 | |
117 | return vq; | |
ac8954a4 OBC |
118 | } |
119 | ||
120 | static void rproc_virtio_del_vqs(struct virtio_device *vdev) | |
121 | { | |
122 | struct virtqueue *vq, *n; | |
123 | struct rproc *rproc = vdev_to_rproc(vdev); | |
7a186941 | 124 | struct rproc_vring *rvring; |
ac8954a4 | 125 | |
41a6ee09 OBC |
126 | /* power down the remote processor before deleting vqs */ |
127 | rproc_shutdown(rproc); | |
128 | ||
ac8954a4 | 129 | list_for_each_entry_safe(vq, n, &vdev->vqs, list) { |
7a186941 OBC |
130 | rvring = vq->priv; |
131 | rvring->vq = NULL; | |
ac8954a4 | 132 | vring_del_virtqueue(vq); |
6db20ea8 | 133 | rproc_free_vring(rvring); |
ac8954a4 | 134 | } |
ac8954a4 OBC |
135 | } |
136 | ||
137 | static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned nvqs, | |
138 | struct virtqueue *vqs[], | |
139 | vq_callback_t *callbacks[], | |
140 | const char *names[]) | |
141 | { | |
142 | struct rproc *rproc = vdev_to_rproc(vdev); | |
143 | int i, ret; | |
144 | ||
ac8954a4 OBC |
145 | for (i = 0; i < nvqs; ++i) { |
146 | vqs[i] = rp_find_vq(vdev, i, callbacks[i], names[i]); | |
147 | if (IS_ERR(vqs[i])) { | |
148 | ret = PTR_ERR(vqs[i]); | |
149 | goto error; | |
150 | } | |
151 | } | |
152 | ||
41a6ee09 OBC |
153 | /* now that the vqs are all set, boot the remote processor */ |
154 | ret = rproc_boot(rproc); | |
155 | if (ret) { | |
b5ab5e24 | 156 | dev_err(&rproc->dev, "rproc_boot() failed %d\n", ret); |
41a6ee09 OBC |
157 | goto error; |
158 | } | |
159 | ||
ac8954a4 OBC |
160 | return 0; |
161 | ||
162 | error: | |
163 | rproc_virtio_del_vqs(vdev); | |
164 | return ret; | |
165 | } | |
166 | ||
167 | /* | |
168 | * We don't support yet real virtio status semantics. | |
169 | * | |
7a186941 | 170 | * The plan is to provide this via the VDEV resource entry |
ac8954a4 OBC |
171 | * which is part of the firmware: this way the remote processor |
172 | * will be able to access the status values as set by us. | |
173 | */ | |
174 | static u8 rproc_virtio_get_status(struct virtio_device *vdev) | |
175 | { | |
176 | return 0; | |
177 | } | |
178 | ||
179 | static void rproc_virtio_set_status(struct virtio_device *vdev, u8 status) | |
180 | { | |
7a186941 | 181 | dev_dbg(&vdev->dev, "status: %d\n", status); |
ac8954a4 OBC |
182 | } |
183 | ||
184 | static void rproc_virtio_reset(struct virtio_device *vdev) | |
185 | { | |
186 | dev_dbg(&vdev->dev, "reset !\n"); | |
187 | } | |
188 | ||
189 | /* provide the vdev features as retrieved from the firmware */ | |
190 | static u32 rproc_virtio_get_features(struct virtio_device *vdev) | |
191 | { | |
7a186941 | 192 | struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); |
ac8954a4 | 193 | |
7a186941 | 194 | return rvdev->dfeatures; |
ac8954a4 OBC |
195 | } |
196 | ||
197 | static void rproc_virtio_finalize_features(struct virtio_device *vdev) | |
198 | { | |
7a186941 | 199 | struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); |
ac8954a4 OBC |
200 | |
201 | /* Give virtio_ring a chance to accept features */ | |
202 | vring_transport_features(vdev); | |
203 | ||
204 | /* | |
205 | * Remember the finalized features of our vdev, and provide it | |
206 | * to the remote processor once it is powered on. | |
207 | * | |
208 | * Similarly to the status field, we don't expose yet the negotiated | |
209 | * features to the remote processors at this point. This will be | |
210 | * fixed as part of a small resource table overhaul and then an | |
211 | * extension of the virtio resource entries. | |
212 | */ | |
7a186941 | 213 | rvdev->gfeatures = vdev->features[0]; |
ac8954a4 OBC |
214 | } |
215 | ||
216 | static struct virtio_config_ops rproc_virtio_config_ops = { | |
217 | .get_features = rproc_virtio_get_features, | |
218 | .finalize_features = rproc_virtio_finalize_features, | |
219 | .find_vqs = rproc_virtio_find_vqs, | |
220 | .del_vqs = rproc_virtio_del_vqs, | |
221 | .reset = rproc_virtio_reset, | |
222 | .set_status = rproc_virtio_set_status, | |
223 | .get_status = rproc_virtio_get_status, | |
224 | }; | |
225 | ||
226 | /* | |
227 | * This function is called whenever vdev is released, and is responsible | |
7183a2a7 | 228 | * to decrement the remote processor's refcount which was taken when vdev was |
ac8954a4 OBC |
229 | * added. |
230 | * | |
231 | * Never call this function directly; it will be called by the driver | |
232 | * core when needed. | |
233 | */ | |
234 | static void rproc_vdev_release(struct device *dev) | |
235 | { | |
236 | struct virtio_device *vdev = dev_to_virtio(dev); | |
6db20ea8 | 237 | struct rproc_vdev *rvdev = vdev_to_rvdev(vdev); |
ac8954a4 OBC |
238 | struct rproc *rproc = vdev_to_rproc(vdev); |
239 | ||
6db20ea8 OBC |
240 | list_del(&rvdev->node); |
241 | kfree(rvdev); | |
242 | ||
7183a2a7 | 243 | put_device(&rproc->dev); |
ac8954a4 OBC |
244 | } |
245 | ||
246 | /** | |
7a186941 OBC |
247 | * rproc_add_virtio_dev() - register an rproc-induced virtio device |
248 | * @rvdev: the remote vdev | |
ac8954a4 | 249 | * |
7a186941 OBC |
250 | * This function registers a virtio device. This vdev's partent is |
251 | * the rproc device. | |
ac8954a4 | 252 | * |
7a186941 | 253 | * Returns 0 on success or an appropriate error value otherwise. |
ac8954a4 | 254 | */ |
7a186941 | 255 | int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id) |
ac8954a4 | 256 | { |
7a186941 | 257 | struct rproc *rproc = rvdev->rproc; |
b5ab5e24 | 258 | struct device *dev = &rproc->dev; |
7a186941 | 259 | struct virtio_device *vdev = &rvdev->vdev; |
ac8954a4 OBC |
260 | int ret; |
261 | ||
7a186941 OBC |
262 | vdev->id.device = id, |
263 | vdev->config = &rproc_virtio_config_ops, | |
264 | vdev->dev.parent = dev; | |
265 | vdev->dev.release = rproc_vdev_release; | |
ac8954a4 OBC |
266 | |
267 | /* | |
268 | * We're indirectly making a non-temporary copy of the rproc pointer | |
269 | * here, because drivers probed with this vdev will indirectly | |
270 | * access the wrapping rproc. | |
271 | * | |
272 | * Therefore we must increment the rproc refcount here, and decrement | |
273 | * it _only_ when the vdev is released. | |
274 | */ | |
7183a2a7 | 275 | get_device(&rproc->dev); |
ac8954a4 | 276 | |
7a186941 | 277 | ret = register_virtio_device(vdev); |
ac8954a4 | 278 | if (ret) { |
7183a2a7 | 279 | put_device(&rproc->dev); |
ac8954a4 | 280 | dev_err(dev, "failed to register vdev: %d\n", ret); |
7a186941 | 281 | goto out; |
ac8954a4 OBC |
282 | } |
283 | ||
7a186941 OBC |
284 | dev_info(dev, "registered %s (type %d)\n", dev_name(&vdev->dev), id); |
285 | ||
286 | out: | |
ac8954a4 OBC |
287 | return ret; |
288 | } | |
289 | ||
290 | /** | |
7a186941 OBC |
291 | * rproc_remove_virtio_dev() - remove an rproc-induced virtio device |
292 | * @rvdev: the remote vdev | |
ac8954a4 | 293 | * |
7a186941 | 294 | * This function unregisters an existing virtio device. |
ac8954a4 | 295 | */ |
7a186941 | 296 | void rproc_remove_virtio_dev(struct rproc_vdev *rvdev) |
ac8954a4 | 297 | { |
ac8954a4 OBC |
298 | unregister_virtio_device(&rvdev->vdev); |
299 | } |