Commit | Line | Data |
---|---|---|
c3bab824 | 1 | // SPDX-License-Identifier: GPL-2.0 |
bcabbcca OBC |
2 | /* |
3 | * Virtio-based remote processor messaging bus | |
4 | * | |
5 | * Copyright (C) 2011 Texas Instruments, Inc. | |
6 | * Copyright (C) 2011 Google, Inc. | |
7 | * | |
8 | * Ohad Ben-Cohen <ohad@wizery.com> | |
9 | * Brian Swetland <swetland@google.com> | |
bcabbcca OBC |
10 | */ |
11 | ||
12 | #define pr_fmt(fmt) "%s: " fmt, __func__ | |
13 | ||
14 | #include <linux/kernel.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/virtio.h> | |
17 | #include <linux/virtio_ids.h> | |
18 | #include <linux/virtio_config.h> | |
19 | #include <linux/scatterlist.h> | |
20 | #include <linux/dma-mapping.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/idr.h> | |
23 | #include <linux/jiffies.h> | |
24 | #include <linux/sched.h> | |
25 | #include <linux/wait.h> | |
26 | #include <linux/rpmsg.h> | |
27 | #include <linux/mutex.h> | |
a16644cb | 28 | #include <linux/of_device.h> |
bcabbcca | 29 | |
8b881c07 BA |
30 | #include "rpmsg_internal.h" |
31 | ||
bcabbcca OBC |
32 | /** |
33 | * struct virtproc_info - virtual remote processor state | |
34 | * @vdev: the virtio device | |
35 | * @rvq: rx virtqueue | |
36 | * @svq: tx virtqueue | |
37 | * @rbufs: kernel address of rx buffers | |
38 | * @sbufs: kernel address of tx buffers | |
b1b98914 | 39 | * @num_bufs: total number of buffers for rx and tx |
f93848f9 | 40 | * @buf_size: size of one rx or tx buffer |
bcabbcca OBC |
41 | * @last_sbuf: index of last tx buffer used |
42 | * @bufs_dma: dma base addr of the buffers | |
43 | * @tx_lock: protects svq, sbufs and sleepers, to allow concurrent senders. | |
44 | * sending a message might require waking up a dozing remote | |
45 | * processor, which involves sleeping, hence the mutex. | |
46 | * @endpoints: idr of local endpoints, allows fast retrieval | |
47 | * @endpoints_lock: lock of the endpoints set | |
48 | * @sendq: wait queue of sending contexts waiting for a tx buffers | |
49 | * @sleepers: number of senders that are waiting for a tx buffer | |
50 | * @ns_ept: the bus's name service endpoint | |
51 | * | |
52 | * This structure stores the rpmsg state of a given virtio remote processor | |
53 | * device (there might be several virtio proc devices for each physical | |
54 | * remote processor). | |
55 | */ | |
56 | struct virtproc_info { | |
57 | struct virtio_device *vdev; | |
58 | struct virtqueue *rvq, *svq; | |
59 | void *rbufs, *sbufs; | |
b1b98914 | 60 | unsigned int num_bufs; |
f93848f9 | 61 | unsigned int buf_size; |
bcabbcca OBC |
62 | int last_sbuf; |
63 | dma_addr_t bufs_dma; | |
64 | struct mutex tx_lock; | |
65 | struct idr endpoints; | |
66 | struct mutex endpoints_lock; | |
67 | wait_queue_head_t sendq; | |
68 | atomic_t sleepers; | |
69 | struct rpmsg_endpoint *ns_ept; | |
70 | }; | |
71 | ||
e88dae5d BA |
72 | /* The feature bitmap for virtio rpmsg */ |
73 | #define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */ | |
74 | ||
75 | /** | |
76 | * struct rpmsg_hdr - common header for all rpmsg messages | |
77 | * @src: source address | |
78 | * @dst: destination address | |
79 | * @reserved: reserved for future use | |
80 | * @len: length of payload (in bytes) | |
81 | * @flags: message flags | |
82 | * @data: @len bytes of message payload data | |
83 | * | |
84 | * Every message sent(/received) on the rpmsg bus begins with this header. | |
85 | */ | |
86 | struct rpmsg_hdr { | |
87 | u32 src; | |
88 | u32 dst; | |
89 | u32 reserved; | |
90 | u16 len; | |
91 | u16 flags; | |
92 | u8 data[0]; | |
93 | } __packed; | |
94 | ||
95 | /** | |
96 | * struct rpmsg_ns_msg - dynamic name service announcement message | |
97 | * @name: name of remote service that is published | |
98 | * @addr: address of remote service that is published | |
99 | * @flags: indicates whether service is created or destroyed | |
100 | * | |
101 | * This message is sent across to publish a new service, or announce | |
102 | * about its removal. When we receive these messages, an appropriate | |
103 | * rpmsg channel (i.e device) is created/destroyed. In turn, the ->probe() | |
104 | * or ->remove() handler of the appropriate rpmsg driver will be invoked | |
105 | * (if/as-soon-as one is registered). | |
106 | */ | |
107 | struct rpmsg_ns_msg { | |
108 | char name[RPMSG_NAME_SIZE]; | |
109 | u32 addr; | |
110 | u32 flags; | |
111 | } __packed; | |
112 | ||
113 | /** | |
114 | * enum rpmsg_ns_flags - dynamic name service announcement flags | |
115 | * | |
116 | * @RPMSG_NS_CREATE: a new remote service was just created | |
117 | * @RPMSG_NS_DESTROY: a known remote service was just destroyed | |
118 | */ | |
119 | enum rpmsg_ns_flags { | |
120 | RPMSG_NS_CREATE = 0, | |
121 | RPMSG_NS_DESTROY = 1, | |
122 | }; | |
123 | ||
3bf950ff BA |
124 | /** |
125 | * @vrp: the remote processor this channel belongs to | |
126 | */ | |
127 | struct virtio_rpmsg_channel { | |
128 | struct rpmsg_device rpdev; | |
129 | ||
130 | struct virtproc_info *vrp; | |
131 | }; | |
132 | ||
133 | #define to_virtio_rpmsg_channel(_rpdev) \ | |
134 | container_of(_rpdev, struct virtio_rpmsg_channel, rpdev) | |
135 | ||
bcabbcca | 136 | /* |
b1b98914 SA |
137 | * We're allocating buffers of 512 bytes each for communications. The |
138 | * number of buffers will be computed from the number of buffers supported | |
139 | * by the vring, upto a maximum of 512 buffers (256 in each direction). | |
bcabbcca OBC |
140 | * |
141 | * Each buffer will have 16 bytes for the msg header and 496 bytes for | |
142 | * the payload. | |
143 | * | |
b1b98914 | 144 | * This will utilize a maximum total space of 256KB for the buffers. |
bcabbcca OBC |
145 | * |
146 | * We might also want to add support for user-provided buffers in time. | |
147 | * This will allow bigger buffer size flexibility, and can also be used | |
148 | * to achieve zero-copy messaging. | |
149 | * | |
150 | * Note that these numbers are purely a decision of this driver - we | |
151 | * can change this without changing anything in the firmware of the remote | |
152 | * processor. | |
153 | */ | |
b1b98914 | 154 | #define MAX_RPMSG_NUM_BUFS (512) |
f93848f9 | 155 | #define MAX_RPMSG_BUF_SIZE (512) |
bcabbcca OBC |
156 | |
157 | /* | |
158 | * Local addresses are dynamically allocated on-demand. | |
159 | * We do not dynamically assign addresses from the low 1024 range, | |
160 | * in order to reserve that address range for predefined services. | |
161 | */ | |
162 | #define RPMSG_RESERVED_ADDRESSES (1024) | |
163 | ||
164 | /* Address 53 is reserved for advertising remote services */ | |
165 | #define RPMSG_NS_ADDR (53) | |
166 | ||
8a228ecf BA |
167 | static void virtio_rpmsg_destroy_ept(struct rpmsg_endpoint *ept); |
168 | static int virtio_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len); | |
169 | static int virtio_rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, | |
170 | u32 dst); | |
171 | static int virtio_rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
172 | u32 dst, void *data, int len); | |
173 | static int virtio_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len); | |
174 | static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, | |
175 | int len, u32 dst); | |
176 | static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
177 | u32 dst, void *data, int len); | |
bcabbcca | 178 | |
8a228ecf BA |
179 | static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { |
180 | .destroy_ept = virtio_rpmsg_destroy_ept, | |
181 | .send = virtio_rpmsg_send, | |
182 | .sendto = virtio_rpmsg_sendto, | |
183 | .send_offchannel = virtio_rpmsg_send_offchannel, | |
184 | .trysend = virtio_rpmsg_trysend, | |
185 | .trysendto = virtio_rpmsg_trysendto, | |
186 | .trysend_offchannel = virtio_rpmsg_trysend_offchannel, | |
187 | }; | |
188 | ||
9dd87c2a LP |
189 | /** |
190 | * rpmsg_sg_init - initialize scatterlist according to cpu address location | |
191 | * @sg: scatterlist to fill | |
192 | * @cpu_addr: virtual address of the buffer | |
193 | * @len: buffer length | |
194 | * | |
195 | * An internal function filling scatterlist according to virtual address | |
196 | * location (in vmalloc or in kernel). | |
197 | */ | |
198 | static void | |
199 | rpmsg_sg_init(struct scatterlist *sg, void *cpu_addr, unsigned int len) | |
200 | { | |
201 | if (is_vmalloc_addr(cpu_addr)) { | |
202 | sg_init_table(sg, 1); | |
203 | sg_set_page(sg, vmalloc_to_page(cpu_addr), len, | |
204 | offset_in_page(cpu_addr)); | |
205 | } else { | |
206 | WARN_ON(!virt_addr_valid(cpu_addr)); | |
207 | sg_init_one(sg, cpu_addr, len); | |
208 | } | |
209 | } | |
210 | ||
5a081caa OBC |
211 | /** |
212 | * __ept_release() - deallocate an rpmsg endpoint | |
213 | * @kref: the ept's reference count | |
214 | * | |
215 | * This function deallocates an ept, and is invoked when its @kref refcount | |
216 | * drops to zero. | |
217 | * | |
218 | * Never invoke this function directly! | |
219 | */ | |
220 | static void __ept_release(struct kref *kref) | |
221 | { | |
222 | struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, | |
223 | refcount); | |
224 | /* | |
225 | * At this point no one holds a reference to ept anymore, | |
226 | * so we can directly free it | |
227 | */ | |
228 | kfree(ept); | |
229 | } | |
230 | ||
bcabbcca OBC |
231 | /* for more info, see below documentation of rpmsg_create_ept() */ |
232 | static struct rpmsg_endpoint *__rpmsg_create_ept(struct virtproc_info *vrp, | |
92e1de51 | 233 | struct rpmsg_device *rpdev, |
0963679c AS |
234 | rpmsg_rx_cb_t cb, |
235 | void *priv, u32 addr) | |
bcabbcca | 236 | { |
d0ffce77 | 237 | int id_min, id_max, id; |
bcabbcca OBC |
238 | struct rpmsg_endpoint *ept; |
239 | struct device *dev = rpdev ? &rpdev->dev : &vrp->vdev->dev; | |
240 | ||
bcabbcca | 241 | ept = kzalloc(sizeof(*ept), GFP_KERNEL); |
a8bb3fd9 | 242 | if (!ept) |
bcabbcca | 243 | return NULL; |
bcabbcca | 244 | |
5a081caa | 245 | kref_init(&ept->refcount); |
15fd943a | 246 | mutex_init(&ept->cb_lock); |
5a081caa | 247 | |
bcabbcca OBC |
248 | ept->rpdev = rpdev; |
249 | ept->cb = cb; | |
250 | ept->priv = priv; | |
8a228ecf | 251 | ept->ops = &virtio_endpoint_ops; |
bcabbcca OBC |
252 | |
253 | /* do we need to allocate a local address ? */ | |
d0ffce77 TH |
254 | if (addr == RPMSG_ADDR_ANY) { |
255 | id_min = RPMSG_RESERVED_ADDRESSES; | |
256 | id_max = 0; | |
257 | } else { | |
258 | id_min = addr; | |
259 | id_max = addr + 1; | |
260 | } | |
bcabbcca OBC |
261 | |
262 | mutex_lock(&vrp->endpoints_lock); | |
263 | ||
264 | /* bind the endpoint to an rpmsg address (and allocate one if needed) */ | |
d0ffce77 TH |
265 | id = idr_alloc(&vrp->endpoints, ept, id_min, id_max, GFP_KERNEL); |
266 | if (id < 0) { | |
267 | dev_err(dev, "idr_alloc failed: %d\n", id); | |
bcabbcca OBC |
268 | goto free_ept; |
269 | } | |
d0ffce77 | 270 | ept->addr = id; |
bcabbcca OBC |
271 | |
272 | mutex_unlock(&vrp->endpoints_lock); | |
273 | ||
274 | return ept; | |
275 | ||
bcabbcca OBC |
276 | free_ept: |
277 | mutex_unlock(&vrp->endpoints_lock); | |
5a081caa | 278 | kref_put(&ept->refcount, __ept_release); |
bcabbcca OBC |
279 | return NULL; |
280 | } | |
281 | ||
36b72c7d BA |
282 | static struct rpmsg_endpoint *virtio_rpmsg_create_ept(struct rpmsg_device *rpdev, |
283 | rpmsg_rx_cb_t cb, | |
284 | void *priv, | |
285 | struct rpmsg_channel_info chinfo) | |
286 | { | |
3bf950ff BA |
287 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
288 | ||
289 | return __rpmsg_create_ept(vch->vrp, rpdev, cb, priv, chinfo.src); | |
36b72c7d BA |
290 | } |
291 | ||
bcabbcca | 292 | /** |
fa2d7795 OBC |
293 | * __rpmsg_destroy_ept() - destroy an existing rpmsg endpoint |
294 | * @vrp: virtproc which owns this ept | |
bcabbcca OBC |
295 | * @ept: endpoing to destroy |
296 | * | |
fa2d7795 OBC |
297 | * An internal function which destroy an ept without assuming it is |
298 | * bound to an rpmsg channel. This is needed for handling the internal | |
299 | * name service endpoint, which isn't bound to an rpmsg channel. | |
300 | * See also __rpmsg_create_ept(). | |
bcabbcca | 301 | */ |
fa2d7795 OBC |
302 | static void |
303 | __rpmsg_destroy_ept(struct virtproc_info *vrp, struct rpmsg_endpoint *ept) | |
bcabbcca | 304 | { |
15fd943a | 305 | /* make sure new inbound messages can't find this ept anymore */ |
bcabbcca OBC |
306 | mutex_lock(&vrp->endpoints_lock); |
307 | idr_remove(&vrp->endpoints, ept->addr); | |
308 | mutex_unlock(&vrp->endpoints_lock); | |
309 | ||
15fd943a OBC |
310 | /* make sure in-flight inbound messages won't invoke cb anymore */ |
311 | mutex_lock(&ept->cb_lock); | |
312 | ept->cb = NULL; | |
313 | mutex_unlock(&ept->cb_lock); | |
314 | ||
5a081caa | 315 | kref_put(&ept->refcount, __ept_release); |
bcabbcca | 316 | } |
fa2d7795 | 317 | |
8a228ecf BA |
318 | static void virtio_rpmsg_destroy_ept(struct rpmsg_endpoint *ept) |
319 | { | |
3bf950ff BA |
320 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(ept->rpdev); |
321 | ||
322 | __rpmsg_destroy_ept(vch->vrp, ept); | |
8a228ecf BA |
323 | } |
324 | ||
36b72c7d BA |
325 | static int virtio_rpmsg_announce_create(struct rpmsg_device *rpdev) |
326 | { | |
3bf950ff BA |
327 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
328 | struct virtproc_info *vrp = vch->vrp; | |
36b72c7d BA |
329 | struct device *dev = &rpdev->dev; |
330 | int err = 0; | |
331 | ||
bcabbcca | 332 | /* need to tell remote processor's name service about this channel ? */ |
b2599ebf | 333 | if (rpdev->announce && rpdev->ept && |
0963679c | 334 | virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { |
bcabbcca OBC |
335 | struct rpmsg_ns_msg nsm; |
336 | ||
337 | strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); | |
2a48d732 | 338 | nsm.addr = rpdev->ept->addr; |
bcabbcca OBC |
339 | nsm.flags = RPMSG_NS_CREATE; |
340 | ||
2a48d732 | 341 | err = rpmsg_sendto(rpdev->ept, &nsm, sizeof(nsm), RPMSG_NS_ADDR); |
bcabbcca OBC |
342 | if (err) |
343 | dev_err(dev, "failed to announce service %d\n", err); | |
344 | } | |
345 | ||
bcabbcca OBC |
346 | return err; |
347 | } | |
348 | ||
36b72c7d | 349 | static int virtio_rpmsg_announce_destroy(struct rpmsg_device *rpdev) |
bcabbcca | 350 | { |
3bf950ff BA |
351 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
352 | struct virtproc_info *vrp = vch->vrp; | |
36b72c7d | 353 | struct device *dev = &rpdev->dev; |
bcabbcca OBC |
354 | int err = 0; |
355 | ||
356 | /* tell remote processor's name service we're removing this channel */ | |
b2599ebf | 357 | if (rpdev->announce && rpdev->ept && |
0963679c | 358 | virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { |
bcabbcca OBC |
359 | struct rpmsg_ns_msg nsm; |
360 | ||
361 | strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); | |
85786724 | 362 | nsm.addr = rpdev->ept->addr; |
bcabbcca OBC |
363 | nsm.flags = RPMSG_NS_DESTROY; |
364 | ||
2a48d732 | 365 | err = rpmsg_sendto(rpdev->ept, &nsm, sizeof(nsm), RPMSG_NS_ADDR); |
bcabbcca OBC |
366 | if (err) |
367 | dev_err(dev, "failed to announce service %d\n", err); | |
368 | } | |
369 | ||
36b72c7d BA |
370 | return err; |
371 | } | |
372 | ||
36b72c7d BA |
373 | static const struct rpmsg_device_ops virtio_rpmsg_ops = { |
374 | .create_ept = virtio_rpmsg_create_ept, | |
375 | .announce_create = virtio_rpmsg_announce_create, | |
376 | .announce_destroy = virtio_rpmsg_announce_destroy, | |
377 | }; | |
378 | ||
b0b03b81 BA |
379 | static void virtio_rpmsg_release_device(struct device *dev) |
380 | { | |
381 | struct rpmsg_device *rpdev = to_rpmsg_device(dev); | |
382 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); | |
383 | ||
384 | kfree(vch); | |
385 | } | |
386 | ||
bcabbcca OBC |
387 | /* |
388 | * create an rpmsg channel using its name and address info. | |
389 | * this function will be used to create both static and dynamic | |
390 | * channels. | |
391 | */ | |
92e1de51 BA |
392 | static struct rpmsg_device *rpmsg_create_channel(struct virtproc_info *vrp, |
393 | struct rpmsg_channel_info *chinfo) | |
bcabbcca | 394 | { |
3bf950ff | 395 | struct virtio_rpmsg_channel *vch; |
92e1de51 | 396 | struct rpmsg_device *rpdev; |
bcabbcca OBC |
397 | struct device *tmp, *dev = &vrp->vdev->dev; |
398 | int ret; | |
399 | ||
400 | /* make sure a similar channel doesn't already exist */ | |
8b881c07 | 401 | tmp = rpmsg_find_device(dev, chinfo); |
bcabbcca OBC |
402 | if (tmp) { |
403 | /* decrement the matched device's refcount back */ | |
404 | put_device(tmp); | |
405 | dev_err(dev, "channel %s:%x:%x already exist\n", | |
406 | chinfo->name, chinfo->src, chinfo->dst); | |
407 | return NULL; | |
408 | } | |
409 | ||
3bf950ff BA |
410 | vch = kzalloc(sizeof(*vch), GFP_KERNEL); |
411 | if (!vch) | |
bcabbcca | 412 | return NULL; |
bcabbcca | 413 | |
3bf950ff BA |
414 | /* Link the channel to our vrp */ |
415 | vch->vrp = vrp; | |
416 | ||
3bf950ff BA |
417 | /* Assign public information to the rpmsg_device */ |
418 | rpdev = &vch->rpdev; | |
bcabbcca OBC |
419 | rpdev->src = chinfo->src; |
420 | rpdev->dst = chinfo->dst; | |
36b72c7d | 421 | rpdev->ops = &virtio_rpmsg_ops; |
bcabbcca OBC |
422 | |
423 | /* | |
424 | * rpmsg server channels has predefined local address (for now), | |
425 | * and their existence needs to be announced remotely | |
426 | */ | |
c8ced113 | 427 | rpdev->announce = rpdev->src != RPMSG_ADDR_ANY; |
bcabbcca OBC |
428 | |
429 | strncpy(rpdev->id.name, chinfo->name, RPMSG_NAME_SIZE); | |
430 | ||
6eed598a | 431 | rpdev->dev.parent = &vrp->vdev->dev; |
b0b03b81 | 432 | rpdev->dev.release = virtio_rpmsg_release_device; |
6eed598a BA |
433 | ret = rpmsg_register_device(rpdev); |
434 | if (ret) | |
435 | return NULL; | |
436 | ||
437 | return rpdev; | |
438 | } | |
439 | ||
bcabbcca OBC |
440 | /* super simple buffer "allocator" that is just enough for now */ |
441 | static void *get_a_tx_buf(struct virtproc_info *vrp) | |
442 | { | |
443 | unsigned int len; | |
444 | void *ret; | |
445 | ||
446 | /* support multiple concurrent senders */ | |
447 | mutex_lock(&vrp->tx_lock); | |
448 | ||
449 | /* | |
450 | * either pick the next unused tx buffer | |
451 | * (half of our buffers are used for sending messages) | |
452 | */ | |
b1b98914 | 453 | if (vrp->last_sbuf < vrp->num_bufs / 2) |
f93848f9 | 454 | ret = vrp->sbufs + vrp->buf_size * vrp->last_sbuf++; |
bcabbcca OBC |
455 | /* or recycle a used one */ |
456 | else | |
457 | ret = virtqueue_get_buf(vrp->svq, &len); | |
458 | ||
459 | mutex_unlock(&vrp->tx_lock); | |
460 | ||
461 | return ret; | |
462 | } | |
463 | ||
464 | /** | |
465 | * rpmsg_upref_sleepers() - enable "tx-complete" interrupts, if needed | |
466 | * @vrp: virtual remote processor state | |
467 | * | |
468 | * This function is called before a sender is blocked, waiting for | |
469 | * a tx buffer to become available. | |
470 | * | |
471 | * If we already have blocking senders, this function merely increases | |
472 | * the "sleepers" reference count, and exits. | |
473 | * | |
474 | * Otherwise, if this is the first sender to block, we also enable | |
475 | * virtio's tx callbacks, so we'd be immediately notified when a tx | |
476 | * buffer is consumed (we rely on virtio's tx callback in order | |
477 | * to wake up sleeping senders as soon as a tx buffer is used by the | |
478 | * remote processor). | |
479 | */ | |
480 | static void rpmsg_upref_sleepers(struct virtproc_info *vrp) | |
481 | { | |
482 | /* support multiple concurrent senders */ | |
483 | mutex_lock(&vrp->tx_lock); | |
484 | ||
485 | /* are we the first sleeping context waiting for tx buffers ? */ | |
486 | if (atomic_inc_return(&vrp->sleepers) == 1) | |
487 | /* enable "tx-complete" interrupts before dozing off */ | |
488 | virtqueue_enable_cb(vrp->svq); | |
489 | ||
490 | mutex_unlock(&vrp->tx_lock); | |
491 | } | |
492 | ||
493 | /** | |
494 | * rpmsg_downref_sleepers() - disable "tx-complete" interrupts, if needed | |
495 | * @vrp: virtual remote processor state | |
496 | * | |
497 | * This function is called after a sender, that waited for a tx buffer | |
498 | * to become available, is unblocked. | |
499 | * | |
500 | * If we still have blocking senders, this function merely decreases | |
501 | * the "sleepers" reference count, and exits. | |
502 | * | |
503 | * Otherwise, if there are no more blocking senders, we also disable | |
504 | * virtio's tx callbacks, to avoid the overhead incurred with handling | |
505 | * those (now redundant) interrupts. | |
506 | */ | |
507 | static void rpmsg_downref_sleepers(struct virtproc_info *vrp) | |
508 | { | |
509 | /* support multiple concurrent senders */ | |
510 | mutex_lock(&vrp->tx_lock); | |
511 | ||
512 | /* are we the last sleeping context waiting for tx buffers ? */ | |
513 | if (atomic_dec_and_test(&vrp->sleepers)) | |
514 | /* disable "tx-complete" interrupts */ | |
515 | virtqueue_disable_cb(vrp->svq); | |
516 | ||
517 | mutex_unlock(&vrp->tx_lock); | |
518 | } | |
519 | ||
520 | /** | |
521 | * rpmsg_send_offchannel_raw() - send a message across to the remote processor | |
522 | * @rpdev: the rpmsg channel | |
523 | * @src: source address | |
524 | * @dst: destination address | |
525 | * @data: payload of message | |
526 | * @len: length of payload | |
527 | * @wait: indicates whether caller should block in case no TX buffers available | |
528 | * | |
529 | * This function is the base implementation for all of the rpmsg sending API. | |
530 | * | |
531 | * It will send @data of length @len to @dst, and say it's from @src. The | |
532 | * message will be sent to the remote processor which the @rpdev channel | |
533 | * belongs to. | |
534 | * | |
535 | * The message is sent using one of the TX buffers that are available for | |
536 | * communication with this remote processor. | |
537 | * | |
538 | * If @wait is true, the caller will be blocked until either a TX buffer is | |
539 | * available, or 15 seconds elapses (we don't want callers to | |
540 | * sleep indefinitely due to misbehaving remote processors), and in that | |
541 | * case -ERESTARTSYS is returned. The number '15' itself was picked | |
542 | * arbitrarily; there's little point in asking drivers to provide a timeout | |
543 | * value themselves. | |
544 | * | |
545 | * Otherwise, if @wait is false, and there are no TX buffers available, | |
546 | * the function will immediately fail, and -ENOMEM will be returned. | |
547 | * | |
548 | * Normally drivers shouldn't use this function directly; instead, drivers | |
549 | * should use the appropriate rpmsg_{try}send{to, _offchannel} API | |
550 | * (see include/linux/rpmsg.h). | |
551 | * | |
552 | * Returns 0 on success and an appropriate error value on failure. | |
553 | */ | |
8a228ecf BA |
554 | static int rpmsg_send_offchannel_raw(struct rpmsg_device *rpdev, |
555 | u32 src, u32 dst, | |
556 | void *data, int len, bool wait) | |
bcabbcca | 557 | { |
3bf950ff BA |
558 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
559 | struct virtproc_info *vrp = vch->vrp; | |
bcabbcca OBC |
560 | struct device *dev = &rpdev->dev; |
561 | struct scatterlist sg; | |
562 | struct rpmsg_hdr *msg; | |
563 | int err; | |
564 | ||
565 | /* bcasting isn't allowed */ | |
566 | if (src == RPMSG_ADDR_ANY || dst == RPMSG_ADDR_ANY) { | |
567 | dev_err(dev, "invalid addr (src 0x%x, dst 0x%x)\n", src, dst); | |
568 | return -EINVAL; | |
569 | } | |
570 | ||
571 | /* | |
572 | * We currently use fixed-sized buffers, and therefore the payload | |
573 | * length is limited. | |
574 | * | |
575 | * One of the possible improvements here is either to support | |
576 | * user-provided buffers (and then we can also support zero-copy | |
577 | * messaging), or to improve the buffer allocator, to support | |
578 | * variable-length buffer sizes. | |
579 | */ | |
f93848f9 | 580 | if (len > vrp->buf_size - sizeof(struct rpmsg_hdr)) { |
bcabbcca OBC |
581 | dev_err(dev, "message is too big (%d)\n", len); |
582 | return -EMSGSIZE; | |
583 | } | |
584 | ||
585 | /* grab a buffer */ | |
586 | msg = get_a_tx_buf(vrp); | |
587 | if (!msg && !wait) | |
588 | return -ENOMEM; | |
589 | ||
590 | /* no free buffer ? wait for one (but bail after 15 seconds) */ | |
591 | while (!msg) { | |
592 | /* enable "tx-complete" interrupts, if not already enabled */ | |
593 | rpmsg_upref_sleepers(vrp); | |
594 | ||
595 | /* | |
596 | * sleep until a free buffer is available or 15 secs elapse. | |
597 | * the timeout period is not configurable because there's | |
598 | * little point in asking drivers to specify that. | |
599 | * if later this happens to be required, it'd be easy to add. | |
600 | */ | |
601 | err = wait_event_interruptible_timeout(vrp->sendq, | |
602 | (msg = get_a_tx_buf(vrp)), | |
603 | msecs_to_jiffies(15000)); | |
604 | ||
605 | /* disable "tx-complete" interrupts if we're the last sleeper */ | |
606 | rpmsg_downref_sleepers(vrp); | |
607 | ||
608 | /* timeout ? */ | |
609 | if (!err) { | |
610 | dev_err(dev, "timeout waiting for a tx buffer\n"); | |
611 | return -ERESTARTSYS; | |
612 | } | |
613 | } | |
614 | ||
615 | msg->len = len; | |
616 | msg->flags = 0; | |
617 | msg->src = src; | |
618 | msg->dst = dst; | |
619 | msg->reserved = 0; | |
620 | memcpy(msg->data, data, len); | |
621 | ||
622 | dev_dbg(dev, "TX From 0x%x, To 0x%x, Len %d, Flags %d, Reserved %d\n", | |
0963679c | 623 | msg->src, msg->dst, msg->len, msg->flags, msg->reserved); |
211e3a93 AS |
624 | #if defined(CONFIG_DYNAMIC_DEBUG) |
625 | dynamic_hex_dump("rpmsg_virtio TX: ", DUMP_PREFIX_NONE, 16, 1, | |
626 | msg, sizeof(*msg) + msg->len, true); | |
627 | #endif | |
bcabbcca | 628 | |
9dd87c2a | 629 | rpmsg_sg_init(&sg, msg, sizeof(*msg) + len); |
bcabbcca OBC |
630 | |
631 | mutex_lock(&vrp->tx_lock); | |
632 | ||
633 | /* add message to the remote processor's virtqueue */ | |
cee51d69 | 634 | err = virtqueue_add_outbuf(vrp->svq, &sg, 1, msg, GFP_KERNEL); |
57e1a373 | 635 | if (err) { |
bcabbcca OBC |
636 | /* |
637 | * need to reclaim the buffer here, otherwise it's lost | |
638 | * (memory won't leak, but rpmsg won't use it again for TX). | |
639 | * this will wait for a buffer management overhaul. | |
640 | */ | |
cee51d69 | 641 | dev_err(dev, "virtqueue_add_outbuf failed: %d\n", err); |
bcabbcca OBC |
642 | goto out; |
643 | } | |
644 | ||
645 | /* tell the remote processor it has a pending message to read */ | |
646 | virtqueue_kick(vrp->svq); | |
bcabbcca OBC |
647 | out: |
648 | mutex_unlock(&vrp->tx_lock); | |
649 | return err; | |
650 | } | |
bcabbcca | 651 | |
8a228ecf BA |
652 | static int virtio_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len) |
653 | { | |
654 | struct rpmsg_device *rpdev = ept->rpdev; | |
655 | u32 src = ept->addr, dst = rpdev->dst; | |
656 | ||
657 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
658 | } | |
659 | ||
660 | static int virtio_rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, | |
661 | u32 dst) | |
662 | { | |
663 | struct rpmsg_device *rpdev = ept->rpdev; | |
664 | u32 src = ept->addr; | |
665 | ||
666 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
667 | } | |
668 | ||
669 | static int virtio_rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
670 | u32 dst, void *data, int len) | |
671 | { | |
672 | struct rpmsg_device *rpdev = ept->rpdev; | |
673 | ||
674 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
675 | } | |
676 | ||
677 | static int virtio_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len) | |
678 | { | |
679 | struct rpmsg_device *rpdev = ept->rpdev; | |
680 | u32 src = ept->addr, dst = rpdev->dst; | |
681 | ||
682 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
683 | } | |
684 | ||
685 | static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, | |
686 | int len, u32 dst) | |
687 | { | |
688 | struct rpmsg_device *rpdev = ept->rpdev; | |
689 | u32 src = ept->addr; | |
690 | ||
691 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
692 | } | |
693 | ||
694 | static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
695 | u32 dst, void *data, int len) | |
696 | { | |
697 | struct rpmsg_device *rpdev = ept->rpdev; | |
698 | ||
699 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
700 | } | |
701 | ||
1aa7d6a5 RT |
702 | static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, |
703 | struct rpmsg_hdr *msg, unsigned int len) | |
bcabbcca | 704 | { |
bcabbcca OBC |
705 | struct rpmsg_endpoint *ept; |
706 | struct scatterlist sg; | |
bcabbcca OBC |
707 | int err; |
708 | ||
bcabbcca | 709 | dev_dbg(dev, "From: 0x%x, To: 0x%x, Len: %d, Flags: %d, Reserved: %d\n", |
0963679c | 710 | msg->src, msg->dst, msg->len, msg->flags, msg->reserved); |
211e3a93 AS |
711 | #if defined(CONFIG_DYNAMIC_DEBUG) |
712 | dynamic_hex_dump("rpmsg_virtio RX: ", DUMP_PREFIX_NONE, 16, 1, | |
713 | msg, sizeof(*msg) + msg->len, true); | |
714 | #endif | |
bcabbcca | 715 | |
9648224e OBC |
716 | /* |
717 | * We currently use fixed-sized buffers, so trivially sanitize | |
718 | * the reported payload length. | |
719 | */ | |
f93848f9 | 720 | if (len > vrp->buf_size || |
0963679c | 721 | msg->len > (len - sizeof(struct rpmsg_hdr))) { |
9648224e | 722 | dev_warn(dev, "inbound msg too big: (%d, %d)\n", len, msg->len); |
1aa7d6a5 | 723 | return -EINVAL; |
9648224e OBC |
724 | } |
725 | ||
bcabbcca OBC |
726 | /* use the dst addr to fetch the callback of the appropriate user */ |
727 | mutex_lock(&vrp->endpoints_lock); | |
5a081caa | 728 | |
bcabbcca | 729 | ept = idr_find(&vrp->endpoints, msg->dst); |
5a081caa OBC |
730 | |
731 | /* let's make sure no one deallocates ept while we use it */ | |
732 | if (ept) | |
733 | kref_get(&ept->refcount); | |
734 | ||
bcabbcca OBC |
735 | mutex_unlock(&vrp->endpoints_lock); |
736 | ||
15fd943a OBC |
737 | if (ept) { |
738 | /* make sure ept->cb doesn't go away while we use it */ | |
739 | mutex_lock(&ept->cb_lock); | |
bcabbcca | 740 | |
15fd943a OBC |
741 | if (ept->cb) |
742 | ept->cb(ept->rpdev, msg->data, msg->len, ept->priv, | |
743 | msg->src); | |
744 | ||
745 | mutex_unlock(&ept->cb_lock); | |
746 | ||
747 | /* farewell, ept, we don't need you anymore */ | |
5a081caa | 748 | kref_put(&ept->refcount, __ept_release); |
15fd943a | 749 | } else |
8a168ca7 | 750 | dev_warn(dev, "msg received with no recipient\n"); |
5a081caa | 751 | |
f1d9e9c7 | 752 | /* publish the real size of the buffer */ |
9dd87c2a | 753 | rpmsg_sg_init(&sg, msg, vrp->buf_size); |
bcabbcca OBC |
754 | |
755 | /* add the buffer back to the remote processor's virtqueue */ | |
cee51d69 | 756 | err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, msg, GFP_KERNEL); |
bcabbcca OBC |
757 | if (err < 0) { |
758 | dev_err(dev, "failed to add a virtqueue buffer: %d\n", err); | |
1aa7d6a5 RT |
759 | return err; |
760 | } | |
761 | ||
762 | return 0; | |
763 | } | |
764 | ||
765 | /* called when an rx buffer is used, and it's time to digest a message */ | |
766 | static void rpmsg_recv_done(struct virtqueue *rvq) | |
767 | { | |
768 | struct virtproc_info *vrp = rvq->vdev->priv; | |
769 | struct device *dev = &rvq->vdev->dev; | |
770 | struct rpmsg_hdr *msg; | |
771 | unsigned int len, msgs_received = 0; | |
772 | int err; | |
773 | ||
774 | msg = virtqueue_get_buf(rvq, &len); | |
775 | if (!msg) { | |
776 | dev_err(dev, "uhm, incoming signal, but no used buffer ?\n"); | |
bcabbcca OBC |
777 | return; |
778 | } | |
779 | ||
1aa7d6a5 RT |
780 | while (msg) { |
781 | err = rpmsg_recv_single(vrp, dev, msg, len); | |
782 | if (err) | |
783 | break; | |
784 | ||
785 | msgs_received++; | |
786 | ||
787 | msg = virtqueue_get_buf(rvq, &len); | |
6c49fbe3 | 788 | } |
1aa7d6a5 RT |
789 | |
790 | dev_dbg(dev, "Received %u messages\n", msgs_received); | |
791 | ||
bcabbcca | 792 | /* tell the remote processor we added another available rx buffer */ |
1aa7d6a5 RT |
793 | if (msgs_received) |
794 | virtqueue_kick(vrp->rvq); | |
bcabbcca OBC |
795 | } |
796 | ||
797 | /* | |
798 | * This is invoked whenever the remote processor completed processing | |
799 | * a TX msg we just sent it, and the buffer is put back to the used ring. | |
800 | * | |
801 | * Normally, though, we suppress this "tx complete" interrupt in order to | |
802 | * avoid the incurred overhead. | |
803 | */ | |
804 | static void rpmsg_xmit_done(struct virtqueue *svq) | |
805 | { | |
806 | struct virtproc_info *vrp = svq->vdev->priv; | |
807 | ||
808 | dev_dbg(&svq->vdev->dev, "%s\n", __func__); | |
809 | ||
810 | /* wake up potential senders that are waiting for a tx buffer */ | |
811 | wake_up_interruptible(&vrp->sendq); | |
812 | } | |
813 | ||
814 | /* invoked when a name service announcement arrives */ | |
4b83c52a BA |
815 | static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len, |
816 | void *priv, u32 src) | |
bcabbcca OBC |
817 | { |
818 | struct rpmsg_ns_msg *msg = data; | |
92e1de51 | 819 | struct rpmsg_device *newch; |
bcabbcca OBC |
820 | struct rpmsg_channel_info chinfo; |
821 | struct virtproc_info *vrp = priv; | |
822 | struct device *dev = &vrp->vdev->dev; | |
823 | int ret; | |
824 | ||
211e3a93 AS |
825 | #if defined(CONFIG_DYNAMIC_DEBUG) |
826 | dynamic_hex_dump("NS announcement: ", DUMP_PREFIX_NONE, 16, 1, | |
827 | data, len, true); | |
828 | #endif | |
bcabbcca OBC |
829 | |
830 | if (len != sizeof(*msg)) { | |
831 | dev_err(dev, "malformed ns msg (%d)\n", len); | |
4b83c52a | 832 | return -EINVAL; |
bcabbcca OBC |
833 | } |
834 | ||
835 | /* | |
836 | * the name service ept does _not_ belong to a real rpmsg channel, | |
837 | * and is handled by the rpmsg bus itself. | |
838 | * for sanity reasons, make sure a valid rpdev has _not_ sneaked | |
839 | * in somehow. | |
840 | */ | |
841 | if (rpdev) { | |
842 | dev_err(dev, "anomaly: ns ept has an rpdev handle\n"); | |
4b83c52a | 843 | return -EINVAL; |
bcabbcca OBC |
844 | } |
845 | ||
846 | /* don't trust the remote processor for null terminating the name */ | |
847 | msg->name[RPMSG_NAME_SIZE - 1] = '\0'; | |
848 | ||
849 | dev_info(dev, "%sing channel %s addr 0x%x\n", | |
0963679c AS |
850 | msg->flags & RPMSG_NS_DESTROY ? "destroy" : "creat", |
851 | msg->name, msg->addr); | |
bcabbcca OBC |
852 | |
853 | strncpy(chinfo.name, msg->name, sizeof(chinfo.name)); | |
854 | chinfo.src = RPMSG_ADDR_ANY; | |
855 | chinfo.dst = msg->addr; | |
856 | ||
857 | if (msg->flags & RPMSG_NS_DESTROY) { | |
5e619b48 | 858 | ret = rpmsg_unregister_device(&vrp->vdev->dev, &chinfo); |
bcabbcca OBC |
859 | if (ret) |
860 | dev_err(dev, "rpmsg_destroy_channel failed: %d\n", ret); | |
861 | } else { | |
862 | newch = rpmsg_create_channel(vrp, &chinfo); | |
863 | if (!newch) | |
864 | dev_err(dev, "rpmsg_create_channel failed\n"); | |
865 | } | |
4b83c52a BA |
866 | |
867 | return 0; | |
bcabbcca OBC |
868 | } |
869 | ||
870 | static int rpmsg_probe(struct virtio_device *vdev) | |
871 | { | |
872 | vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done }; | |
f7ad26ff | 873 | static const char * const names[] = { "input", "output" }; |
bcabbcca OBC |
874 | struct virtqueue *vqs[2]; |
875 | struct virtproc_info *vrp; | |
876 | void *bufs_va; | |
877 | int err = 0, i; | |
b1b98914 | 878 | size_t total_buf_space; |
71e4b8bf | 879 | bool notify; |
bcabbcca OBC |
880 | |
881 | vrp = kzalloc(sizeof(*vrp), GFP_KERNEL); | |
882 | if (!vrp) | |
883 | return -ENOMEM; | |
884 | ||
885 | vrp->vdev = vdev; | |
886 | ||
887 | idr_init(&vrp->endpoints); | |
888 | mutex_init(&vrp->endpoints_lock); | |
889 | mutex_init(&vrp->tx_lock); | |
890 | init_waitqueue_head(&vrp->sendq); | |
891 | ||
892 | /* We expect two virtqueues, rx and tx (and in this order) */ | |
9b2bbdb2 | 893 | err = virtio_find_vqs(vdev, 2, vqs, vq_cbs, names, NULL); |
bcabbcca OBC |
894 | if (err) |
895 | goto free_vrp; | |
896 | ||
897 | vrp->rvq = vqs[0]; | |
898 | vrp->svq = vqs[1]; | |
899 | ||
b1b98914 SA |
900 | /* we expect symmetric tx/rx vrings */ |
901 | WARN_ON(virtqueue_get_vring_size(vrp->rvq) != | |
902 | virtqueue_get_vring_size(vrp->svq)); | |
903 | ||
904 | /* we need less buffers if vrings are small */ | |
905 | if (virtqueue_get_vring_size(vrp->rvq) < MAX_RPMSG_NUM_BUFS / 2) | |
906 | vrp->num_bufs = virtqueue_get_vring_size(vrp->rvq) * 2; | |
907 | else | |
908 | vrp->num_bufs = MAX_RPMSG_NUM_BUFS; | |
909 | ||
f93848f9 LP |
910 | vrp->buf_size = MAX_RPMSG_BUF_SIZE; |
911 | ||
912 | total_buf_space = vrp->num_bufs * vrp->buf_size; | |
b1b98914 | 913 | |
bcabbcca | 914 | /* allocate coherent memory for the buffers */ |
b5ab5e24 | 915 | bufs_va = dma_alloc_coherent(vdev->dev.parent->parent, |
b1b98914 SA |
916 | total_buf_space, &vrp->bufs_dma, |
917 | GFP_KERNEL); | |
3119b487 WY |
918 | if (!bufs_va) { |
919 | err = -ENOMEM; | |
bcabbcca | 920 | goto vqs_del; |
3119b487 | 921 | } |
bcabbcca | 922 | |
8d95b322 AS |
923 | dev_dbg(&vdev->dev, "buffers: va %p, dma %pad\n", |
924 | bufs_va, &vrp->bufs_dma); | |
bcabbcca OBC |
925 | |
926 | /* half of the buffers is dedicated for RX */ | |
927 | vrp->rbufs = bufs_va; | |
928 | ||
929 | /* and half is dedicated for TX */ | |
b1b98914 | 930 | vrp->sbufs = bufs_va + total_buf_space / 2; |
bcabbcca OBC |
931 | |
932 | /* set up the receive buffers */ | |
b1b98914 | 933 | for (i = 0; i < vrp->num_bufs / 2; i++) { |
bcabbcca | 934 | struct scatterlist sg; |
f93848f9 | 935 | void *cpu_addr = vrp->rbufs + i * vrp->buf_size; |
bcabbcca | 936 | |
9dd87c2a | 937 | rpmsg_sg_init(&sg, cpu_addr, vrp->buf_size); |
bcabbcca | 938 | |
cee51d69 | 939 | err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, cpu_addr, |
0963679c | 940 | GFP_KERNEL); |
57e1a373 | 941 | WARN_ON(err); /* sanity check; this can't really happen */ |
bcabbcca OBC |
942 | } |
943 | ||
944 | /* suppress "tx-complete" interrupts */ | |
945 | virtqueue_disable_cb(vrp->svq); | |
946 | ||
947 | vdev->priv = vrp; | |
948 | ||
949 | /* if supported by the remote processor, enable the name service */ | |
950 | if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_NS)) { | |
951 | /* a dedicated endpoint handles the name service msgs */ | |
952 | vrp->ns_ept = __rpmsg_create_ept(vrp, NULL, rpmsg_ns_cb, | |
953 | vrp, RPMSG_NS_ADDR); | |
954 | if (!vrp->ns_ept) { | |
955 | dev_err(&vdev->dev, "failed to create the ns ept\n"); | |
956 | err = -ENOMEM; | |
957 | goto free_coherent; | |
958 | } | |
959 | } | |
960 | ||
71e4b8bf MT |
961 | /* |
962 | * Prepare to kick but don't notify yet - we can't do this before | |
963 | * device is ready. | |
964 | */ | |
965 | notify = virtqueue_kick_prepare(vrp->rvq); | |
966 | ||
967 | /* From this point on, we can notify and get callbacks. */ | |
968 | virtio_device_ready(vdev); | |
969 | ||
bcabbcca | 970 | /* tell the remote processor it can start sending messages */ |
71e4b8bf MT |
971 | /* |
972 | * this might be concurrent with callbacks, but we are only | |
973 | * doing notify, not a full kick here, so that's ok. | |
974 | */ | |
975 | if (notify) | |
976 | virtqueue_notify(vrp->rvq); | |
bcabbcca OBC |
977 | |
978 | dev_info(&vdev->dev, "rpmsg host is online\n"); | |
979 | ||
980 | return 0; | |
981 | ||
982 | free_coherent: | |
b1b98914 SA |
983 | dma_free_coherent(vdev->dev.parent->parent, total_buf_space, |
984 | bufs_va, vrp->bufs_dma); | |
bcabbcca OBC |
985 | vqs_del: |
986 | vdev->config->del_vqs(vrp->vdev); | |
987 | free_vrp: | |
988 | kfree(vrp); | |
989 | return err; | |
990 | } | |
991 | ||
992 | static int rpmsg_remove_device(struct device *dev, void *data) | |
993 | { | |
994 | device_unregister(dev); | |
995 | ||
996 | return 0; | |
997 | } | |
998 | ||
0fe763c5 | 999 | static void rpmsg_remove(struct virtio_device *vdev) |
bcabbcca OBC |
1000 | { |
1001 | struct virtproc_info *vrp = vdev->priv; | |
f93848f9 | 1002 | size_t total_buf_space = vrp->num_bufs * vrp->buf_size; |
bcabbcca OBC |
1003 | int ret; |
1004 | ||
1005 | vdev->config->reset(vdev); | |
1006 | ||
1007 | ret = device_for_each_child(&vdev->dev, NULL, rpmsg_remove_device); | |
1008 | if (ret) | |
1009 | dev_warn(&vdev->dev, "can't remove rpmsg device: %d\n", ret); | |
1010 | ||
fa2d7795 OBC |
1011 | if (vrp->ns_ept) |
1012 | __rpmsg_destroy_ept(vrp, vrp->ns_ept); | |
1013 | ||
bcabbcca OBC |
1014 | idr_destroy(&vrp->endpoints); |
1015 | ||
1016 | vdev->config->del_vqs(vrp->vdev); | |
1017 | ||
b1b98914 SA |
1018 | dma_free_coherent(vdev->dev.parent->parent, total_buf_space, |
1019 | vrp->rbufs, vrp->bufs_dma); | |
bcabbcca OBC |
1020 | |
1021 | kfree(vrp); | |
1022 | } | |
1023 | ||
1024 | static struct virtio_device_id id_table[] = { | |
1025 | { VIRTIO_ID_RPMSG, VIRTIO_DEV_ANY_ID }, | |
1026 | { 0 }, | |
1027 | }; | |
1028 | ||
1029 | static unsigned int features[] = { | |
1030 | VIRTIO_RPMSG_F_NS, | |
1031 | }; | |
1032 | ||
1033 | static struct virtio_driver virtio_ipc_driver = { | |
1034 | .feature_table = features, | |
1035 | .feature_table_size = ARRAY_SIZE(features), | |
1036 | .driver.name = KBUILD_MODNAME, | |
1037 | .driver.owner = THIS_MODULE, | |
1038 | .id_table = id_table, | |
1039 | .probe = rpmsg_probe, | |
0fe763c5 | 1040 | .remove = rpmsg_remove, |
bcabbcca OBC |
1041 | }; |
1042 | ||
1043 | static int __init rpmsg_init(void) | |
1044 | { | |
1045 | int ret; | |
1046 | ||
bcabbcca | 1047 | ret = register_virtio_driver(&virtio_ipc_driver); |
5e619b48 | 1048 | if (ret) |
bcabbcca | 1049 | pr_err("failed to register virtio driver: %d\n", ret); |
bcabbcca OBC |
1050 | |
1051 | return ret; | |
1052 | } | |
96342526 | 1053 | subsys_initcall(rpmsg_init); |
bcabbcca OBC |
1054 | |
1055 | static void __exit rpmsg_fini(void) | |
1056 | { | |
1057 | unregister_virtio_driver(&virtio_ipc_driver); | |
bcabbcca OBC |
1058 | } |
1059 | module_exit(rpmsg_fini); | |
1060 | ||
1061 | MODULE_DEVICE_TABLE(virtio, id_table); | |
1062 | MODULE_DESCRIPTION("Virtio-based remote processor messaging bus"); | |
1063 | MODULE_LICENSE("GPL v2"); |