2 * Remote processor messaging transport (OMAP platform-specific bits)
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 * Copyright (C) 2011 Google, Inc.
7 * Ohad Ben-Cohen <ohad@wizery.com>
8 * Brian Swetland <swetland@google.com>
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.
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.
20 #include <linux/export.h>
21 #include <linux/remoteproc.h>
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>
30 #include "remoteproc_internal.h"
32 /* kick the remote processor, and let it know which virtqueue to poke at */
33 static bool rproc_virtio_notify(struct virtqueue *vq)
35 struct rproc_vring *rvring = vq->priv;
36 struct rproc *rproc = rvring->rvdev->rproc;
37 int notifyid = rvring->notifyid;
39 dev_dbg(&rproc->dev, "kicking vq index: %d\n", notifyid);
41 rproc->ops->kick(rproc, notifyid);
46 * rproc_vq_interrupt() - tell remoteproc that a virtqueue is interrupted
47 * @rproc: handle to the remote processor
48 * @notifyid: index of the signalled virtqueue (unique per this @rproc)
50 * This function should be called by the platform-specific rproc driver,
51 * when the remote processor signals that a specific virtqueue has pending
54 * Returns IRQ_NONE if no message was found in the @notifyid virtqueue,
55 * and otherwise returns IRQ_HANDLED.
57 irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int notifyid)
59 struct rproc_vring *rvring;
61 dev_dbg(&rproc->dev, "vq index %d is interrupted\n", notifyid);
63 rvring = idr_find(&rproc->notifyids, notifyid);
64 if (!rvring || !rvring->vq)
67 return vring_interrupt(0, rvring->vq);
69 EXPORT_SYMBOL(rproc_vq_interrupt);
71 static struct virtqueue *rp_find_vq(struct virtio_device *vdev,
73 void (*callback)(struct virtqueue *vq),
74 const char *name, bool ctx)
76 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
77 struct rproc *rproc = vdev_to_rproc(vdev);
78 struct device *dev = &rproc->dev;
79 struct rproc_mem_entry *mem;
80 struct rproc_vring *rvring;
81 struct fw_rsc_vdev *rsc;
86 /* we're temporarily limited to two virtqueues per rvdev */
87 if (id >= ARRAY_SIZE(rvdev->vring))
88 return ERR_PTR(-EINVAL);
93 /* Search allocated memory region by name */
94 mem = rproc_find_carveout_by_name(rproc, "vdev%dvring%d", rvdev->index,
97 return ERR_PTR(-ENOMEM);
99 rvring = &rvdev->vring[id];
104 size = vring_size(len, rvring->align);
105 memset(addr, 0, size);
107 dev_dbg(dev, "vring%d: va %pK qsz %d notifyid %d\n",
108 id, addr, len, rvring->notifyid);
111 * Create the new vq, and tell virtio we're not interested in
112 * the 'weak' smp barriers, since we're talking with a real device.
114 vq = vring_new_virtqueue(id, len, rvring->align, vdev, false, ctx,
115 addr, rproc_virtio_notify, callback, name);
117 dev_err(dev, "vring_new_virtqueue %s failed\n", name);
118 rproc_free_vring(rvring);
119 return ERR_PTR(-ENOMEM);
125 /* Update vring in resource table */
126 rsc = (void *)rproc->table_ptr + rvdev->rsc_offset;
127 rsc->vring[id].da = mem->da;
132 static void __rproc_virtio_del_vqs(struct virtio_device *vdev)
134 struct virtqueue *vq, *n;
135 struct rproc_vring *rvring;
137 list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
140 vring_del_virtqueue(vq);
144 static void rproc_virtio_del_vqs(struct virtio_device *vdev)
146 __rproc_virtio_del_vqs(vdev);
149 static int rproc_virtio_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
150 struct virtqueue *vqs[],
151 vq_callback_t *callbacks[],
152 const char * const names[],
154 struct irq_affinity *desc)
156 int i, ret, queue_idx = 0;
158 for (i = 0; i < nvqs; ++i) {
164 vqs[i] = rp_find_vq(vdev, queue_idx++, callbacks[i], names[i],
165 ctx ? ctx[i] : false);
166 if (IS_ERR(vqs[i])) {
167 ret = PTR_ERR(vqs[i]);
175 __rproc_virtio_del_vqs(vdev);
179 static u8 rproc_virtio_get_status(struct virtio_device *vdev)
181 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
182 struct fw_rsc_vdev *rsc;
184 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
189 static void rproc_virtio_set_status(struct virtio_device *vdev, u8 status)
191 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
192 struct fw_rsc_vdev *rsc;
194 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
196 rsc->status = status;
197 dev_dbg(&vdev->dev, "status: %d\n", status);
200 static void rproc_virtio_reset(struct virtio_device *vdev)
202 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
203 struct fw_rsc_vdev *rsc;
205 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
208 dev_dbg(&vdev->dev, "reset !\n");
211 /* provide the vdev features as retrieved from the firmware */
212 static u64 rproc_virtio_get_features(struct virtio_device *vdev)
214 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
215 struct fw_rsc_vdev *rsc;
217 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
219 return rsc->dfeatures;
222 static void rproc_transport_features(struct virtio_device *vdev)
225 * Packed ring isn't enabled on remoteproc for now,
226 * because remoteproc uses vring_new_virtqueue() which
227 * creates virtio rings on preallocated memory.
229 __virtio_clear_bit(vdev, VIRTIO_F_RING_PACKED);
232 static int rproc_virtio_finalize_features(struct virtio_device *vdev)
234 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
235 struct fw_rsc_vdev *rsc;
237 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
239 /* Give virtio_ring a chance to accept features */
240 vring_transport_features(vdev);
242 /* Give virtio_rproc a chance to accept features. */
243 rproc_transport_features(vdev);
245 /* Make sure we don't have any features > 32 bits! */
246 BUG_ON((u32)vdev->features != vdev->features);
249 * Remember the finalized features of our vdev, and provide it
250 * to the remote processor once it is powered on.
252 rsc->gfeatures = vdev->features;
257 static void rproc_virtio_get(struct virtio_device *vdev, unsigned int offset,
258 void *buf, unsigned int len)
260 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
261 struct fw_rsc_vdev *rsc;
264 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
265 cfg = &rsc->vring[rsc->num_of_vrings];
267 if (offset + len > rsc->config_len || offset + len < len) {
268 dev_err(&vdev->dev, "rproc_virtio_get: access out of bounds\n");
272 memcpy(buf, cfg + offset, len);
275 static void rproc_virtio_set(struct virtio_device *vdev, unsigned int offset,
276 const void *buf, unsigned int len)
278 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
279 struct fw_rsc_vdev *rsc;
282 rsc = (void *)rvdev->rproc->table_ptr + rvdev->rsc_offset;
283 cfg = &rsc->vring[rsc->num_of_vrings];
285 if (offset + len > rsc->config_len || offset + len < len) {
286 dev_err(&vdev->dev, "rproc_virtio_set: access out of bounds\n");
290 memcpy(cfg + offset, buf, len);
293 static const struct virtio_config_ops rproc_virtio_config_ops = {
294 .get_features = rproc_virtio_get_features,
295 .finalize_features = rproc_virtio_finalize_features,
296 .find_vqs = rproc_virtio_find_vqs,
297 .del_vqs = rproc_virtio_del_vqs,
298 .reset = rproc_virtio_reset,
299 .set_status = rproc_virtio_set_status,
300 .get_status = rproc_virtio_get_status,
301 .get = rproc_virtio_get,
302 .set = rproc_virtio_set,
306 * This function is called whenever vdev is released, and is responsible
307 * to decrement the remote processor's refcount which was taken when vdev was
310 * Never call this function directly; it will be called by the driver
313 static void rproc_virtio_dev_release(struct device *dev)
315 struct virtio_device *vdev = dev_to_virtio(dev);
316 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
317 struct rproc *rproc = vdev_to_rproc(vdev);
319 kref_put(&rvdev->refcount, rproc_vdev_release);
321 put_device(&rproc->dev);
325 * rproc_add_virtio_dev() - register an rproc-induced virtio device
326 * @rvdev: the remote vdev
328 * This function registers a virtio device. This vdev's partent is
331 * Returns 0 on success or an appropriate error value otherwise.
333 int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
335 struct rproc *rproc = rvdev->rproc;
336 struct device *dev = &rproc->dev;
337 struct virtio_device *vdev = &rvdev->vdev;
340 vdev->id.device = id,
341 vdev->config = &rproc_virtio_config_ops,
342 vdev->dev.parent = dev;
343 vdev->dev.release = rproc_virtio_dev_release;
346 * We're indirectly making a non-temporary copy of the rproc pointer
347 * here, because drivers probed with this vdev will indirectly
348 * access the wrapping rproc.
350 * Therefore we must increment the rproc refcount here, and decrement
351 * it _only_ when the vdev is released.
353 get_device(&rproc->dev);
355 /* Reference the vdev and vring allocations */
356 kref_get(&rvdev->refcount);
358 ret = register_virtio_device(vdev);
360 put_device(&vdev->dev);
361 dev_err(dev, "failed to register vdev: %d\n", ret);
365 dev_info(dev, "registered %s (type %d)\n", dev_name(&vdev->dev), id);
372 * rproc_remove_virtio_dev() - remove an rproc-induced virtio device
373 * @rvdev: the remote vdev
375 * This function unregisters an existing virtio device.
377 void rproc_remove_virtio_dev(struct rproc_vdev *rvdev)
379 unregister_virtio_device(&rvdev->vdev);