xref: /openbmc/linux/drivers/misc/fastrpc.c (revision d2a99dbd)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2011-2018, The Linux Foundation. All rights reserved.
3 // Copyright (c) 2018, Linaro Limited
4 
5 #include <linux/completion.h>
6 #include <linux/device.h>
7 #include <linux/dma-buf.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/idr.h>
10 #include <linux/list.h>
11 #include <linux/miscdevice.h>
12 #include <linux/module.h>
13 #include <linux/of_address.h>
14 #include <linux/of.h>
15 #include <linux/sort.h>
16 #include <linux/of_platform.h>
17 #include <linux/rpmsg.h>
18 #include <linux/scatterlist.h>
19 #include <linux/slab.h>
20 #include <uapi/misc/fastrpc.h>
21 
22 #define ADSP_DOMAIN_ID (0)
23 #define MDSP_DOMAIN_ID (1)
24 #define SDSP_DOMAIN_ID (2)
25 #define CDSP_DOMAIN_ID (3)
26 #define FASTRPC_DEV_MAX		4 /* adsp, mdsp, slpi, cdsp*/
27 #define FASTRPC_MAX_SESSIONS	9 /*8 compute, 1 cpz*/
28 #define FASTRPC_ALIGN		128
29 #define FASTRPC_MAX_FDLIST	16
30 #define FASTRPC_MAX_CRCLIST	64
31 #define FASTRPC_PHYS(p)	((p) & 0xffffffff)
32 #define FASTRPC_CTX_MAX (256)
33 #define FASTRPC_INIT_HANDLE	1
34 #define FASTRPC_CTXID_MASK (0xFF0)
35 #define INIT_FILELEN_MAX (64 * 1024 * 1024)
36 #define FASTRPC_DEVICE_NAME	"fastrpc"
37 
38 /* Retrives number of input buffers from the scalars parameter */
39 #define REMOTE_SCALARS_INBUFS(sc)	(((sc) >> 16) & 0x0ff)
40 
41 /* Retrives number of output buffers from the scalars parameter */
42 #define REMOTE_SCALARS_OUTBUFS(sc)	(((sc) >> 8) & 0x0ff)
43 
44 /* Retrives number of input handles from the scalars parameter */
45 #define REMOTE_SCALARS_INHANDLES(sc)	(((sc) >> 4) & 0x0f)
46 
47 /* Retrives number of output handles from the scalars parameter */
48 #define REMOTE_SCALARS_OUTHANDLES(sc)	((sc) & 0x0f)
49 
50 #define REMOTE_SCALARS_LENGTH(sc)	(REMOTE_SCALARS_INBUFS(sc) +   \
51 					 REMOTE_SCALARS_OUTBUFS(sc) +  \
52 					 REMOTE_SCALARS_INHANDLES(sc)+ \
53 					 REMOTE_SCALARS_OUTHANDLES(sc))
54 #define FASTRPC_BUILD_SCALARS(attr, method, in, out, oin, oout)  \
55 				(((attr & 0x07) << 29) |		\
56 				((method & 0x1f) << 24) |	\
57 				((in & 0xff) << 16) |		\
58 				((out & 0xff) <<  8) |		\
59 				((oin & 0x0f) <<  4) |		\
60 				(oout & 0x0f))
61 
62 #define FASTRPC_SCALARS(method, in, out) \
63 		FASTRPC_BUILD_SCALARS(0, method, in, out, 0, 0)
64 
65 #define FASTRPC_CREATE_PROCESS_NARGS	6
66 /* Remote Method id table */
67 #define FASTRPC_RMID_INIT_ATTACH	0
68 #define FASTRPC_RMID_INIT_RELEASE	1
69 #define FASTRPC_RMID_INIT_CREATE	6
70 #define FASTRPC_RMID_INIT_CREATE_ATTR	7
71 #define FASTRPC_RMID_INIT_CREATE_STATIC	8
72 
73 #define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)
74 
75 static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
76 						"sdsp", "cdsp"};
77 struct fastrpc_phy_page {
78 	u64 addr;		/* physical address */
79 	u64 size;		/* size of contiguous region */
80 };
81 
82 struct fastrpc_invoke_buf {
83 	u32 num;		/* number of contiguous regions */
84 	u32 pgidx;		/* index to start of contiguous region */
85 };
86 
87 struct fastrpc_remote_arg {
88 	u64 pv;
89 	u64 len;
90 };
91 
92 struct fastrpc_msg {
93 	int pid;		/* process group id */
94 	int tid;		/* thread id */
95 	u64 ctx;		/* invoke caller context */
96 	u32 handle;	/* handle to invoke */
97 	u32 sc;		/* scalars structure describing the data */
98 	u64 addr;		/* physical address */
99 	u64 size;		/* size of contiguous region */
100 };
101 
102 struct fastrpc_invoke_rsp {
103 	u64 ctx;		/* invoke caller context */
104 	int retval;		/* invoke return value */
105 };
106 
107 struct fastrpc_buf_overlap {
108 	u64 start;
109 	u64 end;
110 	int raix;
111 	u64 mstart;
112 	u64 mend;
113 	u64 offset;
114 };
115 
116 struct fastrpc_buf {
117 	struct fastrpc_user *fl;
118 	struct dma_buf *dmabuf;
119 	struct device *dev;
120 	void *virt;
121 	u64 phys;
122 	u64 size;
123 	/* Lock for dma buf attachments */
124 	struct mutex lock;
125 	struct list_head attachments;
126 };
127 
128 struct fastrpc_dma_buf_attachment {
129 	struct device *dev;
130 	struct sg_table sgt;
131 	struct list_head node;
132 };
133 
134 struct fastrpc_map {
135 	struct list_head node;
136 	struct fastrpc_user *fl;
137 	int fd;
138 	struct dma_buf *buf;
139 	struct sg_table *table;
140 	struct dma_buf_attachment *attach;
141 	u64 phys;
142 	u64 size;
143 	void *va;
144 	u64 len;
145 	struct kref refcount;
146 };
147 
148 struct fastrpc_invoke_ctx {
149 	int nscalars;
150 	int nbufs;
151 	int retval;
152 	int pid;
153 	int tgid;
154 	u32 sc;
155 	u32 *crc;
156 	u64 ctxid;
157 	u64 msg_sz;
158 	struct kref refcount;
159 	struct list_head node; /* list of ctxs */
160 	struct completion work;
161 	struct work_struct put_work;
162 	struct fastrpc_msg msg;
163 	struct fastrpc_user *fl;
164 	struct fastrpc_remote_arg *rpra;
165 	struct fastrpc_map **maps;
166 	struct fastrpc_buf *buf;
167 	struct fastrpc_invoke_args *args;
168 	struct fastrpc_buf_overlap *olaps;
169 	struct fastrpc_channel_ctx *cctx;
170 };
171 
172 struct fastrpc_session_ctx {
173 	struct device *dev;
174 	int sid;
175 	bool used;
176 	bool valid;
177 };
178 
179 struct fastrpc_channel_ctx {
180 	int domain_id;
181 	int sesscount;
182 	struct rpmsg_device *rpdev;
183 	struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
184 	spinlock_t lock;
185 	struct idr ctx_idr;
186 	struct list_head users;
187 	struct miscdevice miscdev;
188 	struct kref refcount;
189 };
190 
191 struct fastrpc_user {
192 	struct list_head user;
193 	struct list_head maps;
194 	struct list_head pending;
195 
196 	struct fastrpc_channel_ctx *cctx;
197 	struct fastrpc_session_ctx *sctx;
198 	struct fastrpc_buf *init_mem;
199 
200 	int tgid;
201 	int pd;
202 	/* Lock for lists */
203 	spinlock_t lock;
204 	/* lock for allocations */
205 	struct mutex mutex;
206 };
207 
208 static void fastrpc_free_map(struct kref *ref)
209 {
210 	struct fastrpc_map *map;
211 
212 	map = container_of(ref, struct fastrpc_map, refcount);
213 
214 	if (map->table) {
215 		dma_buf_unmap_attachment(map->attach, map->table,
216 					 DMA_BIDIRECTIONAL);
217 		dma_buf_detach(map->buf, map->attach);
218 		dma_buf_put(map->buf);
219 	}
220 
221 	kfree(map);
222 }
223 
224 static void fastrpc_map_put(struct fastrpc_map *map)
225 {
226 	if (map)
227 		kref_put(&map->refcount, fastrpc_free_map);
228 }
229 
230 static void fastrpc_map_get(struct fastrpc_map *map)
231 {
232 	if (map)
233 		kref_get(&map->refcount);
234 }
235 
236 static int fastrpc_map_find(struct fastrpc_user *fl, int fd,
237 			    struct fastrpc_map **ppmap)
238 {
239 	struct fastrpc_map *map = NULL;
240 
241 	mutex_lock(&fl->mutex);
242 	list_for_each_entry(map, &fl->maps, node) {
243 		if (map->fd == fd) {
244 			fastrpc_map_get(map);
245 			*ppmap = map;
246 			mutex_unlock(&fl->mutex);
247 			return 0;
248 		}
249 	}
250 	mutex_unlock(&fl->mutex);
251 
252 	return -ENOENT;
253 }
254 
255 static void fastrpc_buf_free(struct fastrpc_buf *buf)
256 {
257 	dma_free_coherent(buf->dev, buf->size, buf->virt,
258 			  FASTRPC_PHYS(buf->phys));
259 	kfree(buf);
260 }
261 
262 static int fastrpc_buf_alloc(struct fastrpc_user *fl, struct device *dev,
263 			     u64 size, struct fastrpc_buf **obuf)
264 {
265 	struct fastrpc_buf *buf;
266 
267 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
268 	if (!buf)
269 		return -ENOMEM;
270 
271 	INIT_LIST_HEAD(&buf->attachments);
272 	mutex_init(&buf->lock);
273 
274 	buf->fl = fl;
275 	buf->virt = NULL;
276 	buf->phys = 0;
277 	buf->size = size;
278 	buf->dev = dev;
279 
280 	buf->virt = dma_alloc_coherent(dev, buf->size, (dma_addr_t *)&buf->phys,
281 				       GFP_KERNEL);
282 	if (!buf->virt) {
283 		mutex_destroy(&buf->lock);
284 		kfree(buf);
285 		return -ENOMEM;
286 	}
287 
288 	if (fl->sctx && fl->sctx->sid)
289 		buf->phys += ((u64)fl->sctx->sid << 32);
290 
291 	*obuf = buf;
292 
293 	return 0;
294 }
295 
296 static void fastrpc_channel_ctx_free(struct kref *ref)
297 {
298 	struct fastrpc_channel_ctx *cctx;
299 
300 	cctx = container_of(ref, struct fastrpc_channel_ctx, refcount);
301 
302 	kfree(cctx);
303 }
304 
305 static void fastrpc_channel_ctx_get(struct fastrpc_channel_ctx *cctx)
306 {
307 	kref_get(&cctx->refcount);
308 }
309 
310 static void fastrpc_channel_ctx_put(struct fastrpc_channel_ctx *cctx)
311 {
312 	kref_put(&cctx->refcount, fastrpc_channel_ctx_free);
313 }
314 
315 static void fastrpc_context_free(struct kref *ref)
316 {
317 	struct fastrpc_invoke_ctx *ctx;
318 	struct fastrpc_channel_ctx *cctx;
319 	unsigned long flags;
320 	int i;
321 
322 	ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
323 	cctx = ctx->cctx;
324 
325 	for (i = 0; i < ctx->nscalars; i++)
326 		fastrpc_map_put(ctx->maps[i]);
327 
328 	if (ctx->buf)
329 		fastrpc_buf_free(ctx->buf);
330 
331 	spin_lock_irqsave(&cctx->lock, flags);
332 	idr_remove(&cctx->ctx_idr, ctx->ctxid >> 4);
333 	spin_unlock_irqrestore(&cctx->lock, flags);
334 
335 	kfree(ctx->maps);
336 	kfree(ctx->olaps);
337 	kfree(ctx);
338 
339 	fastrpc_channel_ctx_put(cctx);
340 }
341 
342 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
343 {
344 	kref_get(&ctx->refcount);
345 }
346 
347 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
348 {
349 	kref_put(&ctx->refcount, fastrpc_context_free);
350 }
351 
352 static void fastrpc_context_put_wq(struct work_struct *work)
353 {
354 	struct fastrpc_invoke_ctx *ctx =
355 			container_of(work, struct fastrpc_invoke_ctx, put_work);
356 
357 	fastrpc_context_put(ctx);
358 }
359 
360 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
361 static int olaps_cmp(const void *a, const void *b)
362 {
363 	struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
364 	struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
365 	/* sort with lowest starting buffer first */
366 	int st = CMP(pa->start, pb->start);
367 	/* sort with highest ending buffer first */
368 	int ed = CMP(pb->end, pa->end);
369 
370 	return st == 0 ? ed : st;
371 }
372 
373 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
374 {
375 	u64 max_end = 0;
376 	int i;
377 
378 	for (i = 0; i < ctx->nbufs; ++i) {
379 		ctx->olaps[i].start = ctx->args[i].ptr;
380 		ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
381 		ctx->olaps[i].raix = i;
382 	}
383 
384 	sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
385 
386 	for (i = 0; i < ctx->nbufs; ++i) {
387 		/* Falling inside previous range */
388 		if (ctx->olaps[i].start < max_end) {
389 			ctx->olaps[i].mstart = max_end;
390 			ctx->olaps[i].mend = ctx->olaps[i].end;
391 			ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
392 
393 			if (ctx->olaps[i].end > max_end) {
394 				max_end = ctx->olaps[i].end;
395 			} else {
396 				ctx->olaps[i].mend = 0;
397 				ctx->olaps[i].mstart = 0;
398 			}
399 
400 		} else  {
401 			ctx->olaps[i].mend = ctx->olaps[i].end;
402 			ctx->olaps[i].mstart = ctx->olaps[i].start;
403 			ctx->olaps[i].offset = 0;
404 			max_end = ctx->olaps[i].end;
405 		}
406 	}
407 }
408 
409 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
410 			struct fastrpc_user *user, u32 kernel, u32 sc,
411 			struct fastrpc_invoke_args *args)
412 {
413 	struct fastrpc_channel_ctx *cctx = user->cctx;
414 	struct fastrpc_invoke_ctx *ctx = NULL;
415 	unsigned long flags;
416 	int ret;
417 
418 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
419 	if (!ctx)
420 		return ERR_PTR(-ENOMEM);
421 
422 	INIT_LIST_HEAD(&ctx->node);
423 	ctx->fl = user;
424 	ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
425 	ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
426 		     REMOTE_SCALARS_OUTBUFS(sc);
427 
428 	if (ctx->nscalars) {
429 		ctx->maps = kcalloc(ctx->nscalars,
430 				    sizeof(*ctx->maps), GFP_KERNEL);
431 		if (!ctx->maps) {
432 			kfree(ctx);
433 			return ERR_PTR(-ENOMEM);
434 		}
435 		ctx->olaps = kcalloc(ctx->nscalars,
436 				    sizeof(*ctx->olaps), GFP_KERNEL);
437 		if (!ctx->olaps) {
438 			kfree(ctx->maps);
439 			kfree(ctx);
440 			return ERR_PTR(-ENOMEM);
441 		}
442 		ctx->args = args;
443 		fastrpc_get_buff_overlaps(ctx);
444 	}
445 
446 	/* Released in fastrpc_context_put() */
447 	fastrpc_channel_ctx_get(cctx);
448 
449 	ctx->sc = sc;
450 	ctx->retval = -1;
451 	ctx->pid = current->pid;
452 	ctx->tgid = user->tgid;
453 	ctx->cctx = cctx;
454 	init_completion(&ctx->work);
455 	INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
456 
457 	spin_lock(&user->lock);
458 	list_add_tail(&ctx->node, &user->pending);
459 	spin_unlock(&user->lock);
460 
461 	spin_lock_irqsave(&cctx->lock, flags);
462 	ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
463 			       FASTRPC_CTX_MAX, GFP_ATOMIC);
464 	if (ret < 0) {
465 		spin_unlock_irqrestore(&cctx->lock, flags);
466 		goto err_idr;
467 	}
468 	ctx->ctxid = ret << 4;
469 	spin_unlock_irqrestore(&cctx->lock, flags);
470 
471 	kref_init(&ctx->refcount);
472 
473 	return ctx;
474 err_idr:
475 	spin_lock(&user->lock);
476 	list_del(&ctx->node);
477 	spin_unlock(&user->lock);
478 	fastrpc_channel_ctx_put(cctx);
479 	kfree(ctx->maps);
480 	kfree(ctx->olaps);
481 	kfree(ctx);
482 
483 	return ERR_PTR(ret);
484 }
485 
486 static struct sg_table *
487 fastrpc_map_dma_buf(struct dma_buf_attachment *attachment,
488 		    enum dma_data_direction dir)
489 {
490 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
491 	struct sg_table *table;
492 
493 	table = &a->sgt;
494 
495 	if (!dma_map_sg(attachment->dev, table->sgl, table->nents, dir))
496 		return ERR_PTR(-ENOMEM);
497 
498 	return table;
499 }
500 
501 static void fastrpc_unmap_dma_buf(struct dma_buf_attachment *attach,
502 				  struct sg_table *table,
503 				  enum dma_data_direction dir)
504 {
505 	dma_unmap_sg(attach->dev, table->sgl, table->nents, dir);
506 }
507 
508 static void fastrpc_release(struct dma_buf *dmabuf)
509 {
510 	struct fastrpc_buf *buffer = dmabuf->priv;
511 
512 	fastrpc_buf_free(buffer);
513 }
514 
515 static int fastrpc_dma_buf_attach(struct dma_buf *dmabuf,
516 				  struct dma_buf_attachment *attachment)
517 {
518 	struct fastrpc_dma_buf_attachment *a;
519 	struct fastrpc_buf *buffer = dmabuf->priv;
520 	int ret;
521 
522 	a = kzalloc(sizeof(*a), GFP_KERNEL);
523 	if (!a)
524 		return -ENOMEM;
525 
526 	ret = dma_get_sgtable(buffer->dev, &a->sgt, buffer->virt,
527 			      FASTRPC_PHYS(buffer->phys), buffer->size);
528 	if (ret < 0) {
529 		dev_err(buffer->dev, "failed to get scatterlist from DMA API\n");
530 		kfree(a);
531 		return -EINVAL;
532 	}
533 
534 	a->dev = attachment->dev;
535 	INIT_LIST_HEAD(&a->node);
536 	attachment->priv = a;
537 
538 	mutex_lock(&buffer->lock);
539 	list_add(&a->node, &buffer->attachments);
540 	mutex_unlock(&buffer->lock);
541 
542 	return 0;
543 }
544 
545 static void fastrpc_dma_buf_detatch(struct dma_buf *dmabuf,
546 				    struct dma_buf_attachment *attachment)
547 {
548 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
549 	struct fastrpc_buf *buffer = dmabuf->priv;
550 
551 	mutex_lock(&buffer->lock);
552 	list_del(&a->node);
553 	mutex_unlock(&buffer->lock);
554 	sg_free_table(&a->sgt);
555 	kfree(a);
556 }
557 
558 static void *fastrpc_kmap(struct dma_buf *dmabuf, unsigned long pgnum)
559 {
560 	struct fastrpc_buf *buf = dmabuf->priv;
561 
562 	return buf->virt ? buf->virt + pgnum * PAGE_SIZE : NULL;
563 }
564 
565 static void *fastrpc_vmap(struct dma_buf *dmabuf)
566 {
567 	struct fastrpc_buf *buf = dmabuf->priv;
568 
569 	return buf->virt;
570 }
571 
572 static int fastrpc_mmap(struct dma_buf *dmabuf,
573 			struct vm_area_struct *vma)
574 {
575 	struct fastrpc_buf *buf = dmabuf->priv;
576 	size_t size = vma->vm_end - vma->vm_start;
577 
578 	return dma_mmap_coherent(buf->dev, vma, buf->virt,
579 				 FASTRPC_PHYS(buf->phys), size);
580 }
581 
582 static const struct dma_buf_ops fastrpc_dma_buf_ops = {
583 	.attach = fastrpc_dma_buf_attach,
584 	.detach = fastrpc_dma_buf_detatch,
585 	.map_dma_buf = fastrpc_map_dma_buf,
586 	.unmap_dma_buf = fastrpc_unmap_dma_buf,
587 	.mmap = fastrpc_mmap,
588 	.map = fastrpc_kmap,
589 	.vmap = fastrpc_vmap,
590 	.release = fastrpc_release,
591 };
592 
593 static int fastrpc_map_create(struct fastrpc_user *fl, int fd,
594 			      u64 len, struct fastrpc_map **ppmap)
595 {
596 	struct fastrpc_session_ctx *sess = fl->sctx;
597 	struct fastrpc_map *map = NULL;
598 	int err = 0;
599 
600 	if (!fastrpc_map_find(fl, fd, ppmap))
601 		return 0;
602 
603 	map = kzalloc(sizeof(*map), GFP_KERNEL);
604 	if (!map)
605 		return -ENOMEM;
606 
607 	INIT_LIST_HEAD(&map->node);
608 	map->fl = fl;
609 	map->fd = fd;
610 	map->buf = dma_buf_get(fd);
611 	if (IS_ERR(map->buf)) {
612 		err = PTR_ERR(map->buf);
613 		goto get_err;
614 	}
615 
616 	map->attach = dma_buf_attach(map->buf, sess->dev);
617 	if (IS_ERR(map->attach)) {
618 		dev_err(sess->dev, "Failed to attach dmabuf\n");
619 		err = PTR_ERR(map->attach);
620 		goto attach_err;
621 	}
622 
623 	map->table = dma_buf_map_attachment(map->attach, DMA_BIDIRECTIONAL);
624 	if (IS_ERR(map->table)) {
625 		err = PTR_ERR(map->table);
626 		goto map_err;
627 	}
628 
629 	map->phys = sg_dma_address(map->table->sgl);
630 	map->phys += ((u64)fl->sctx->sid << 32);
631 	map->size = len;
632 	map->va = sg_virt(map->table->sgl);
633 	map->len = len;
634 	kref_init(&map->refcount);
635 
636 	spin_lock(&fl->lock);
637 	list_add_tail(&map->node, &fl->maps);
638 	spin_unlock(&fl->lock);
639 	*ppmap = map;
640 
641 	return 0;
642 
643 map_err:
644 	dma_buf_detach(map->buf, map->attach);
645 attach_err:
646 	dma_buf_put(map->buf);
647 get_err:
648 	kfree(map);
649 
650 	return err;
651 }
652 
653 /*
654  * Fastrpc payload buffer with metadata looks like:
655  *
656  * >>>>>>  START of METADATA <<<<<<<<<
657  * +---------------------------------+
658  * |           Arguments             |
659  * | type:(struct fastrpc_remote_arg)|
660  * |             (0 - N)             |
661  * +---------------------------------+
662  * |         Invoke Buffer list      |
663  * | type:(struct fastrpc_invoke_buf)|
664  * |           (0 - N)               |
665  * +---------------------------------+
666  * |         Page info list          |
667  * | type:(struct fastrpc_phy_page)  |
668  * |             (0 - N)             |
669  * +---------------------------------+
670  * |         Optional info           |
671  * |(can be specific to SoC/Firmware)|
672  * +---------------------------------+
673  * >>>>>>>>  END of METADATA <<<<<<<<<
674  * +---------------------------------+
675  * |         Inline ARGS             |
676  * |            (0-N)                |
677  * +---------------------------------+
678  */
679 
680 static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx)
681 {
682 	int size = 0;
683 
684 	size = (sizeof(struct fastrpc_remote_arg) +
685 		sizeof(struct fastrpc_invoke_buf) +
686 		sizeof(struct fastrpc_phy_page)) * ctx->nscalars +
687 		sizeof(u64) * FASTRPC_MAX_FDLIST +
688 		sizeof(u32) * FASTRPC_MAX_CRCLIST;
689 
690 	return size;
691 }
692 
693 static u64 fastrpc_get_payload_size(struct fastrpc_invoke_ctx *ctx, int metalen)
694 {
695 	u64 size = 0;
696 	int i;
697 
698 	size = ALIGN(metalen, FASTRPC_ALIGN);
699 	for (i = 0; i < ctx->nscalars; i++) {
700 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1) {
701 
702 			if (ctx->olaps[i].offset == 0)
703 				size = ALIGN(size, FASTRPC_ALIGN);
704 
705 			size += (ctx->olaps[i].mend - ctx->olaps[i].mstart);
706 		}
707 	}
708 
709 	return size;
710 }
711 
712 static int fastrpc_create_maps(struct fastrpc_invoke_ctx *ctx)
713 {
714 	struct device *dev = ctx->fl->sctx->dev;
715 	int i, err;
716 
717 	for (i = 0; i < ctx->nscalars; ++i) {
718 		/* Make sure reserved field is set to 0 */
719 		if (ctx->args[i].reserved)
720 			return -EINVAL;
721 
722 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1 ||
723 		    ctx->args[i].length == 0)
724 			continue;
725 
726 		err = fastrpc_map_create(ctx->fl, ctx->args[i].fd,
727 					 ctx->args[i].length, &ctx->maps[i]);
728 		if (err) {
729 			dev_err(dev, "Error Creating map %d\n", err);
730 			return -EINVAL;
731 		}
732 
733 	}
734 	return 0;
735 }
736 
737 static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
738 {
739 	struct device *dev = ctx->fl->sctx->dev;
740 	struct fastrpc_remote_arg *rpra;
741 	struct fastrpc_invoke_buf *list;
742 	struct fastrpc_phy_page *pages;
743 	int inbufs, i, oix, err = 0;
744 	u64 len, rlen, pkt_size;
745 	u64 pg_start, pg_end;
746 	uintptr_t args;
747 	int metalen;
748 
749 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
750 	metalen = fastrpc_get_meta_size(ctx);
751 	pkt_size = fastrpc_get_payload_size(ctx, metalen);
752 
753 	err = fastrpc_create_maps(ctx);
754 	if (err)
755 		return err;
756 
757 	ctx->msg_sz = pkt_size;
758 
759 	err = fastrpc_buf_alloc(ctx->fl, dev, pkt_size, &ctx->buf);
760 	if (err)
761 		return err;
762 
763 	rpra = ctx->buf->virt;
764 	list = ctx->buf->virt + ctx->nscalars * sizeof(*rpra);
765 	pages = ctx->buf->virt + ctx->nscalars * (sizeof(*list) +
766 		sizeof(*rpra));
767 	args = (uintptr_t)ctx->buf->virt + metalen;
768 	rlen = pkt_size - metalen;
769 	ctx->rpra = rpra;
770 
771 	for (oix = 0; oix < ctx->nbufs; ++oix) {
772 		int mlen;
773 
774 		i = ctx->olaps[oix].raix;
775 		len = ctx->args[i].length;
776 
777 		rpra[i].pv = 0;
778 		rpra[i].len = len;
779 		list[i].num = len ? 1 : 0;
780 		list[i].pgidx = i;
781 
782 		if (!len)
783 			continue;
784 
785 		if (ctx->maps[i]) {
786 			struct vm_area_struct *vma = NULL;
787 
788 			rpra[i].pv = (u64) ctx->args[i].ptr;
789 			pages[i].addr = ctx->maps[i]->phys;
790 
791 			vma = find_vma(current->mm, ctx->args[i].ptr);
792 			if (vma)
793 				pages[i].addr += ctx->args[i].ptr -
794 						 vma->vm_start;
795 
796 			pg_start = (ctx->args[i].ptr & PAGE_MASK) >> PAGE_SHIFT;
797 			pg_end = ((ctx->args[i].ptr + len - 1) & PAGE_MASK) >>
798 				  PAGE_SHIFT;
799 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
800 
801 		} else {
802 
803 			if (ctx->olaps[oix].offset == 0) {
804 				rlen -= ALIGN(args, FASTRPC_ALIGN) - args;
805 				args = ALIGN(args, FASTRPC_ALIGN);
806 			}
807 
808 			mlen = ctx->olaps[oix].mend - ctx->olaps[oix].mstart;
809 
810 			if (rlen < mlen)
811 				goto bail;
812 
813 			rpra[i].pv = args - ctx->olaps[oix].offset;
814 			pages[i].addr = ctx->buf->phys -
815 					ctx->olaps[oix].offset +
816 					(pkt_size - rlen);
817 			pages[i].addr = pages[i].addr &	PAGE_MASK;
818 
819 			pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
820 			pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
821 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
822 			args = args + mlen;
823 			rlen -= mlen;
824 		}
825 
826 		if (i < inbufs && !ctx->maps[i]) {
827 			void *dst = (void *)(uintptr_t)rpra[i].pv;
828 			void *src = (void *)(uintptr_t)ctx->args[i].ptr;
829 
830 			if (!kernel) {
831 				if (copy_from_user(dst, (void __user *)src,
832 						   len)) {
833 					err = -EFAULT;
834 					goto bail;
835 				}
836 			} else {
837 				memcpy(dst, src, len);
838 			}
839 		}
840 	}
841 
842 	for (i = ctx->nbufs; i < ctx->nscalars; ++i) {
843 		rpra[i].pv = (u64) ctx->args[i].ptr;
844 		rpra[i].len = ctx->args[i].length;
845 		list[i].num = ctx->args[i].length ? 1 : 0;
846 		list[i].pgidx = i;
847 		pages[i].addr = ctx->maps[i]->phys;
848 		pages[i].size = ctx->maps[i]->size;
849 	}
850 
851 bail:
852 	if (err)
853 		dev_err(dev, "Error: get invoke args failed:%d\n", err);
854 
855 	return err;
856 }
857 
858 static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
859 			    u32 kernel)
860 {
861 	struct fastrpc_remote_arg *rpra = ctx->rpra;
862 	int i, inbufs;
863 
864 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
865 
866 	for (i = inbufs; i < ctx->nbufs; ++i) {
867 		void *src = (void *)(uintptr_t)rpra[i].pv;
868 		void *dst = (void *)(uintptr_t)ctx->args[i].ptr;
869 		u64 len = rpra[i].len;
870 
871 		if (!kernel) {
872 			if (copy_to_user((void __user *)dst, src, len))
873 				return -EFAULT;
874 		} else {
875 			memcpy(dst, src, len);
876 		}
877 	}
878 
879 	return 0;
880 }
881 
882 static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
883 			       struct fastrpc_invoke_ctx *ctx,
884 			       u32 kernel, uint32_t handle)
885 {
886 	struct fastrpc_channel_ctx *cctx;
887 	struct fastrpc_user *fl = ctx->fl;
888 	struct fastrpc_msg *msg = &ctx->msg;
889 
890 	cctx = fl->cctx;
891 	msg->pid = fl->tgid;
892 	msg->tid = current->pid;
893 
894 	if (kernel)
895 		msg->pid = 0;
896 
897 	msg->ctx = ctx->ctxid | fl->pd;
898 	msg->handle = handle;
899 	msg->sc = ctx->sc;
900 	msg->addr = ctx->buf ? ctx->buf->phys : 0;
901 	msg->size = roundup(ctx->msg_sz, PAGE_SIZE);
902 	fastrpc_context_get(ctx);
903 
904 	return rpmsg_send(cctx->rpdev->ept, (void *)msg, sizeof(*msg));
905 }
906 
907 static int fastrpc_internal_invoke(struct fastrpc_user *fl,  u32 kernel,
908 				   u32 handle, u32 sc,
909 				   struct fastrpc_invoke_args *args)
910 {
911 	struct fastrpc_invoke_ctx *ctx = NULL;
912 	int err = 0;
913 
914 	if (!fl->sctx)
915 		return -EINVAL;
916 
917 	if (!fl->cctx->rpdev)
918 		return -EPIPE;
919 
920 	ctx = fastrpc_context_alloc(fl, kernel, sc, args);
921 	if (IS_ERR(ctx))
922 		return PTR_ERR(ctx);
923 
924 	if (ctx->nscalars) {
925 		err = fastrpc_get_args(kernel, ctx);
926 		if (err)
927 			goto bail;
928 	}
929 
930 	/* make sure that all CPU memory writes are seen by DSP */
931 	dma_wmb();
932 	/* Send invoke buffer to remote dsp */
933 	err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
934 	if (err)
935 		goto bail;
936 
937 	/* Wait for remote dsp to respond or time out */
938 	err = wait_for_completion_interruptible(&ctx->work);
939 	if (err)
940 		goto bail;
941 
942 	/* Check the response from remote dsp */
943 	err = ctx->retval;
944 	if (err)
945 		goto bail;
946 
947 	if (ctx->nscalars) {
948 		/* make sure that all memory writes by DSP are seen by CPU */
949 		dma_rmb();
950 		/* populate all the output buffers with results */
951 		err = fastrpc_put_args(ctx, kernel);
952 		if (err)
953 			goto bail;
954 	}
955 
956 bail:
957 	/* We are done with this compute context, remove it from pending list */
958 	spin_lock(&fl->lock);
959 	list_del(&ctx->node);
960 	spin_unlock(&fl->lock);
961 	fastrpc_context_put(ctx);
962 
963 	if (err)
964 		dev_dbg(fl->sctx->dev, "Error: Invoke Failed %d\n", err);
965 
966 	return err;
967 }
968 
969 static int fastrpc_init_create_process(struct fastrpc_user *fl,
970 					char __user *argp)
971 {
972 	struct fastrpc_init_create init;
973 	struct fastrpc_invoke_args *args;
974 	struct fastrpc_phy_page pages[1];
975 	struct fastrpc_map *map = NULL;
976 	struct fastrpc_buf *imem = NULL;
977 	int memlen;
978 	int err;
979 	struct {
980 		int pgid;
981 		u32 namelen;
982 		u32 filelen;
983 		u32 pageslen;
984 		u32 attrs;
985 		u32 siglen;
986 	} inbuf;
987 	u32 sc;
988 
989 	args = kcalloc(FASTRPC_CREATE_PROCESS_NARGS, sizeof(*args), GFP_KERNEL);
990 	if (!args)
991 		return -ENOMEM;
992 
993 	if (copy_from_user(&init, argp, sizeof(init))) {
994 		err = -EFAULT;
995 		goto err;
996 	}
997 
998 	if (init.filelen > INIT_FILELEN_MAX) {
999 		err = -EINVAL;
1000 		goto err;
1001 	}
1002 
1003 	inbuf.pgid = fl->tgid;
1004 	inbuf.namelen = strlen(current->comm) + 1;
1005 	inbuf.filelen = init.filelen;
1006 	inbuf.pageslen = 1;
1007 	inbuf.attrs = init.attrs;
1008 	inbuf.siglen = init.siglen;
1009 	fl->pd = 1;
1010 
1011 	if (init.filelen && init.filefd) {
1012 		err = fastrpc_map_create(fl, init.filefd, init.filelen, &map);
1013 		if (err)
1014 			goto err;
1015 	}
1016 
1017 	memlen = ALIGN(max(INIT_FILELEN_MAX, (int)init.filelen * 4),
1018 		       1024 * 1024);
1019 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, memlen,
1020 				&imem);
1021 	if (err)
1022 		goto err_alloc;
1023 
1024 	fl->init_mem = imem;
1025 	args[0].ptr = (u64)(uintptr_t)&inbuf;
1026 	args[0].length = sizeof(inbuf);
1027 	args[0].fd = -1;
1028 
1029 	args[1].ptr = (u64)(uintptr_t)current->comm;
1030 	args[1].length = inbuf.namelen;
1031 	args[1].fd = -1;
1032 
1033 	args[2].ptr = (u64) init.file;
1034 	args[2].length = inbuf.filelen;
1035 	args[2].fd = init.filefd;
1036 
1037 	pages[0].addr = imem->phys;
1038 	pages[0].size = imem->size;
1039 
1040 	args[3].ptr = (u64)(uintptr_t) pages;
1041 	args[3].length = 1 * sizeof(*pages);
1042 	args[3].fd = -1;
1043 
1044 	args[4].ptr = (u64)(uintptr_t)&inbuf.attrs;
1045 	args[4].length = sizeof(inbuf.attrs);
1046 	args[4].fd = -1;
1047 
1048 	args[5].ptr = (u64)(uintptr_t) &inbuf.siglen;
1049 	args[5].length = sizeof(inbuf.siglen);
1050 	args[5].fd = -1;
1051 
1052 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE, 4, 0);
1053 	if (init.attrs)
1054 		sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE_ATTR, 6, 0);
1055 
1056 	err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1057 				      sc, args);
1058 	if (err)
1059 		goto err_invoke;
1060 
1061 	kfree(args);
1062 
1063 	return 0;
1064 
1065 err_invoke:
1066 	fl->init_mem = NULL;
1067 	fastrpc_buf_free(imem);
1068 err_alloc:
1069 	if (map) {
1070 		spin_lock(&fl->lock);
1071 		list_del(&map->node);
1072 		spin_unlock(&fl->lock);
1073 		fastrpc_map_put(map);
1074 	}
1075 err:
1076 	kfree(args);
1077 
1078 	return err;
1079 }
1080 
1081 static struct fastrpc_session_ctx *fastrpc_session_alloc(
1082 					struct fastrpc_channel_ctx *cctx)
1083 {
1084 	struct fastrpc_session_ctx *session = NULL;
1085 	unsigned long flags;
1086 	int i;
1087 
1088 	spin_lock_irqsave(&cctx->lock, flags);
1089 	for (i = 0; i < cctx->sesscount; i++) {
1090 		if (!cctx->session[i].used && cctx->session[i].valid) {
1091 			cctx->session[i].used = true;
1092 			session = &cctx->session[i];
1093 			break;
1094 		}
1095 	}
1096 	spin_unlock_irqrestore(&cctx->lock, flags);
1097 
1098 	return session;
1099 }
1100 
1101 static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
1102 				 struct fastrpc_session_ctx *session)
1103 {
1104 	unsigned long flags;
1105 
1106 	spin_lock_irqsave(&cctx->lock, flags);
1107 	session->used = false;
1108 	spin_unlock_irqrestore(&cctx->lock, flags);
1109 }
1110 
1111 static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
1112 {
1113 	struct fastrpc_invoke_args args[1];
1114 	int tgid = 0;
1115 	u32 sc;
1116 
1117 	tgid = fl->tgid;
1118 	args[0].ptr = (u64)(uintptr_t) &tgid;
1119 	args[0].length = sizeof(tgid);
1120 	args[0].fd = -1;
1121 	args[0].reserved = 0;
1122 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_RELEASE, 1, 0);
1123 
1124 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1125 				       sc, &args[0]);
1126 }
1127 
1128 static int fastrpc_device_release(struct inode *inode, struct file *file)
1129 {
1130 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1131 	struct fastrpc_channel_ctx *cctx = fl->cctx;
1132 	struct fastrpc_invoke_ctx *ctx, *n;
1133 	struct fastrpc_map *map, *m;
1134 	unsigned long flags;
1135 
1136 	fastrpc_release_current_dsp_process(fl);
1137 
1138 	spin_lock_irqsave(&cctx->lock, flags);
1139 	list_del(&fl->user);
1140 	spin_unlock_irqrestore(&cctx->lock, flags);
1141 
1142 	if (fl->init_mem)
1143 		fastrpc_buf_free(fl->init_mem);
1144 
1145 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
1146 		list_del(&ctx->node);
1147 		fastrpc_context_put(ctx);
1148 	}
1149 
1150 	list_for_each_entry_safe(map, m, &fl->maps, node) {
1151 		list_del(&map->node);
1152 		fastrpc_map_put(map);
1153 	}
1154 
1155 	fastrpc_session_free(cctx, fl->sctx);
1156 	fastrpc_channel_ctx_put(cctx);
1157 
1158 	mutex_destroy(&fl->mutex);
1159 	kfree(fl);
1160 	file->private_data = NULL;
1161 
1162 	return 0;
1163 }
1164 
1165 static int fastrpc_device_open(struct inode *inode, struct file *filp)
1166 {
1167 	struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
1168 	struct fastrpc_user *fl = NULL;
1169 	unsigned long flags;
1170 
1171 	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
1172 	if (!fl)
1173 		return -ENOMEM;
1174 
1175 	/* Released in fastrpc_device_release() */
1176 	fastrpc_channel_ctx_get(cctx);
1177 
1178 	filp->private_data = fl;
1179 	spin_lock_init(&fl->lock);
1180 	mutex_init(&fl->mutex);
1181 	INIT_LIST_HEAD(&fl->pending);
1182 	INIT_LIST_HEAD(&fl->maps);
1183 	INIT_LIST_HEAD(&fl->user);
1184 	fl->tgid = current->tgid;
1185 	fl->cctx = cctx;
1186 
1187 	fl->sctx = fastrpc_session_alloc(cctx);
1188 	if (!fl->sctx) {
1189 		dev_err(&cctx->rpdev->dev, "No session available\n");
1190 		mutex_destroy(&fl->mutex);
1191 		kfree(fl);
1192 
1193 		return -EBUSY;
1194 	}
1195 
1196 	spin_lock_irqsave(&cctx->lock, flags);
1197 	list_add_tail(&fl->user, &cctx->users);
1198 	spin_unlock_irqrestore(&cctx->lock, flags);
1199 
1200 	return 0;
1201 }
1202 
1203 static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
1204 {
1205 	struct fastrpc_alloc_dma_buf bp;
1206 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1207 	struct fastrpc_buf *buf = NULL;
1208 	int err;
1209 
1210 	if (copy_from_user(&bp, argp, sizeof(bp)))
1211 		return -EFAULT;
1212 
1213 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, bp.size, &buf);
1214 	if (err)
1215 		return err;
1216 	exp_info.ops = &fastrpc_dma_buf_ops;
1217 	exp_info.size = bp.size;
1218 	exp_info.flags = O_RDWR;
1219 	exp_info.priv = buf;
1220 	buf->dmabuf = dma_buf_export(&exp_info);
1221 	if (IS_ERR(buf->dmabuf)) {
1222 		err = PTR_ERR(buf->dmabuf);
1223 		fastrpc_buf_free(buf);
1224 		return err;
1225 	}
1226 
1227 	bp.fd = dma_buf_fd(buf->dmabuf, O_ACCMODE);
1228 	if (bp.fd < 0) {
1229 		dma_buf_put(buf->dmabuf);
1230 		return -EINVAL;
1231 	}
1232 
1233 	if (copy_to_user(argp, &bp, sizeof(bp))) {
1234 		dma_buf_put(buf->dmabuf);
1235 		return -EFAULT;
1236 	}
1237 
1238 	return 0;
1239 }
1240 
1241 static int fastrpc_init_attach(struct fastrpc_user *fl)
1242 {
1243 	struct fastrpc_invoke_args args[1];
1244 	int tgid = fl->tgid;
1245 	u32 sc;
1246 
1247 	args[0].ptr = (u64)(uintptr_t) &tgid;
1248 	args[0].length = sizeof(tgid);
1249 	args[0].fd = -1;
1250 	args[0].reserved = 0;
1251 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
1252 	fl->pd = 0;
1253 
1254 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1255 				       sc, &args[0]);
1256 }
1257 
1258 static int fastrpc_invoke(struct fastrpc_user *fl, char __user *argp)
1259 {
1260 	struct fastrpc_invoke_args *args = NULL;
1261 	struct fastrpc_invoke inv;
1262 	u32 nscalars;
1263 	int err;
1264 
1265 	if (copy_from_user(&inv, argp, sizeof(inv)))
1266 		return -EFAULT;
1267 
1268 	/* nscalars is truncated here to max supported value */
1269 	nscalars = REMOTE_SCALARS_LENGTH(inv.sc);
1270 	if (nscalars) {
1271 		args = kcalloc(nscalars, sizeof(*args), GFP_KERNEL);
1272 		if (!args)
1273 			return -ENOMEM;
1274 
1275 		if (copy_from_user(args, (void __user *)(uintptr_t)inv.args,
1276 				   nscalars * sizeof(*args))) {
1277 			kfree(args);
1278 			return -EFAULT;
1279 		}
1280 	}
1281 
1282 	err = fastrpc_internal_invoke(fl, false, inv.handle, inv.sc, args);
1283 	kfree(args);
1284 
1285 	return err;
1286 }
1287 
1288 static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
1289 				 unsigned long arg)
1290 {
1291 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1292 	char __user *argp = (char __user *)arg;
1293 	int err;
1294 
1295 	switch (cmd) {
1296 	case FASTRPC_IOCTL_INVOKE:
1297 		err = fastrpc_invoke(fl, argp);
1298 		break;
1299 	case FASTRPC_IOCTL_INIT_ATTACH:
1300 		err = fastrpc_init_attach(fl);
1301 		break;
1302 	case FASTRPC_IOCTL_INIT_CREATE:
1303 		err = fastrpc_init_create_process(fl, argp);
1304 		break;
1305 	case FASTRPC_IOCTL_ALLOC_DMA_BUFF:
1306 		err = fastrpc_dmabuf_alloc(fl, argp);
1307 		break;
1308 	default:
1309 		err = -ENOTTY;
1310 		break;
1311 	}
1312 
1313 	return err;
1314 }
1315 
1316 static const struct file_operations fastrpc_fops = {
1317 	.open = fastrpc_device_open,
1318 	.release = fastrpc_device_release,
1319 	.unlocked_ioctl = fastrpc_device_ioctl,
1320 	.compat_ioctl = fastrpc_device_ioctl,
1321 };
1322 
1323 static int fastrpc_cb_probe(struct platform_device *pdev)
1324 {
1325 	struct fastrpc_channel_ctx *cctx;
1326 	struct fastrpc_session_ctx *sess;
1327 	struct device *dev = &pdev->dev;
1328 	int i, sessions = 0;
1329 	unsigned long flags;
1330 	int rc;
1331 
1332 	cctx = dev_get_drvdata(dev->parent);
1333 	if (!cctx)
1334 		return -EINVAL;
1335 
1336 	of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
1337 
1338 	spin_lock_irqsave(&cctx->lock, flags);
1339 	sess = &cctx->session[cctx->sesscount];
1340 	sess->used = false;
1341 	sess->valid = true;
1342 	sess->dev = dev;
1343 	dev_set_drvdata(dev, sess);
1344 
1345 	if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
1346 		dev_info(dev, "FastRPC Session ID not specified in DT\n");
1347 
1348 	if (sessions > 0) {
1349 		struct fastrpc_session_ctx *dup_sess;
1350 
1351 		for (i = 1; i < sessions; i++) {
1352 			if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
1353 				break;
1354 			dup_sess = &cctx->session[cctx->sesscount];
1355 			memcpy(dup_sess, sess, sizeof(*dup_sess));
1356 		}
1357 	}
1358 	cctx->sesscount++;
1359 	spin_unlock_irqrestore(&cctx->lock, flags);
1360 	rc = dma_set_mask(dev, DMA_BIT_MASK(32));
1361 	if (rc) {
1362 		dev_err(dev, "32-bit DMA enable failed\n");
1363 		return rc;
1364 	}
1365 
1366 	return 0;
1367 }
1368 
1369 static int fastrpc_cb_remove(struct platform_device *pdev)
1370 {
1371 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
1372 	struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
1373 	unsigned long flags;
1374 	int i;
1375 
1376 	spin_lock_irqsave(&cctx->lock, flags);
1377 	for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
1378 		if (cctx->session[i].sid == sess->sid) {
1379 			cctx->session[i].valid = false;
1380 			cctx->sesscount--;
1381 		}
1382 	}
1383 	spin_unlock_irqrestore(&cctx->lock, flags);
1384 
1385 	return 0;
1386 }
1387 
1388 static const struct of_device_id fastrpc_match_table[] = {
1389 	{ .compatible = "qcom,fastrpc-compute-cb", },
1390 	{}
1391 };
1392 
1393 static struct platform_driver fastrpc_cb_driver = {
1394 	.probe = fastrpc_cb_probe,
1395 	.remove = fastrpc_cb_remove,
1396 	.driver = {
1397 		.name = "qcom,fastrpc-cb",
1398 		.of_match_table = fastrpc_match_table,
1399 		.suppress_bind_attrs = true,
1400 	},
1401 };
1402 
1403 static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
1404 {
1405 	struct device *rdev = &rpdev->dev;
1406 	struct fastrpc_channel_ctx *data;
1407 	int i, err, domain_id = -1;
1408 	const char *domain;
1409 
1410 	err = of_property_read_string(rdev->of_node, "label", &domain);
1411 	if (err) {
1412 		dev_info(rdev, "FastRPC Domain not specified in DT\n");
1413 		return err;
1414 	}
1415 
1416 	for (i = 0; i <= CDSP_DOMAIN_ID; i++) {
1417 		if (!strcmp(domains[i], domain)) {
1418 			domain_id = i;
1419 			break;
1420 		}
1421 	}
1422 
1423 	if (domain_id < 0) {
1424 		dev_info(rdev, "FastRPC Invalid Domain ID %d\n", domain_id);
1425 		return -EINVAL;
1426 	}
1427 
1428 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1429 	if (!data)
1430 		return -ENOMEM;
1431 
1432 	data->miscdev.minor = MISC_DYNAMIC_MINOR;
1433 	data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
1434 				domains[domain_id]);
1435 	data->miscdev.fops = &fastrpc_fops;
1436 	err = misc_register(&data->miscdev);
1437 	if (err)
1438 		return err;
1439 
1440 	kref_init(&data->refcount);
1441 
1442 	dev_set_drvdata(&rpdev->dev, data);
1443 	dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
1444 	INIT_LIST_HEAD(&data->users);
1445 	spin_lock_init(&data->lock);
1446 	idr_init(&data->ctx_idr);
1447 	data->domain_id = domain_id;
1448 	data->rpdev = rpdev;
1449 
1450 	return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
1451 }
1452 
1453 static void fastrpc_notify_users(struct fastrpc_user *user)
1454 {
1455 	struct fastrpc_invoke_ctx *ctx;
1456 
1457 	spin_lock(&user->lock);
1458 	list_for_each_entry(ctx, &user->pending, node)
1459 		complete(&ctx->work);
1460 	spin_unlock(&user->lock);
1461 }
1462 
1463 static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
1464 {
1465 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1466 	struct fastrpc_user *user;
1467 	unsigned long flags;
1468 
1469 	spin_lock_irqsave(&cctx->lock, flags);
1470 	list_for_each_entry(user, &cctx->users, user)
1471 		fastrpc_notify_users(user);
1472 	spin_unlock_irqrestore(&cctx->lock, flags);
1473 
1474 	misc_deregister(&cctx->miscdev);
1475 	of_platform_depopulate(&rpdev->dev);
1476 
1477 	cctx->rpdev = NULL;
1478 	fastrpc_channel_ctx_put(cctx);
1479 }
1480 
1481 static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
1482 				  int len, void *priv, u32 addr)
1483 {
1484 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1485 	struct fastrpc_invoke_rsp *rsp = data;
1486 	struct fastrpc_invoke_ctx *ctx;
1487 	unsigned long flags;
1488 	unsigned long ctxid;
1489 
1490 	if (len < sizeof(*rsp))
1491 		return -EINVAL;
1492 
1493 	ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
1494 
1495 	spin_lock_irqsave(&cctx->lock, flags);
1496 	ctx = idr_find(&cctx->ctx_idr, ctxid);
1497 	spin_unlock_irqrestore(&cctx->lock, flags);
1498 
1499 	if (!ctx) {
1500 		dev_err(&rpdev->dev, "No context ID matches response\n");
1501 		return -ENOENT;
1502 	}
1503 
1504 	ctx->retval = rsp->retval;
1505 	complete(&ctx->work);
1506 
1507 	/*
1508 	 * The DMA buffer associated with the context cannot be freed in
1509 	 * interrupt context so schedule it through a worker thread to
1510 	 * avoid a kernel BUG.
1511 	 */
1512 	schedule_work(&ctx->put_work);
1513 
1514 	return 0;
1515 }
1516 
1517 static const struct of_device_id fastrpc_rpmsg_of_match[] = {
1518 	{ .compatible = "qcom,fastrpc" },
1519 	{ },
1520 };
1521 MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
1522 
1523 static struct rpmsg_driver fastrpc_driver = {
1524 	.probe = fastrpc_rpmsg_probe,
1525 	.remove = fastrpc_rpmsg_remove,
1526 	.callback = fastrpc_rpmsg_callback,
1527 	.drv = {
1528 		.name = "qcom,fastrpc",
1529 		.of_match_table = fastrpc_rpmsg_of_match,
1530 	},
1531 };
1532 
1533 static int fastrpc_init(void)
1534 {
1535 	int ret;
1536 
1537 	ret = platform_driver_register(&fastrpc_cb_driver);
1538 	if (ret < 0) {
1539 		pr_err("fastrpc: failed to register cb driver\n");
1540 		return ret;
1541 	}
1542 
1543 	ret = register_rpmsg_driver(&fastrpc_driver);
1544 	if (ret < 0) {
1545 		pr_err("fastrpc: failed to register rpmsg driver\n");
1546 		platform_driver_unregister(&fastrpc_cb_driver);
1547 		return ret;
1548 	}
1549 
1550 	return 0;
1551 }
1552 module_init(fastrpc_init);
1553 
1554 static void fastrpc_exit(void)
1555 {
1556 	platform_driver_unregister(&fastrpc_cb_driver);
1557 	unregister_rpmsg_driver(&fastrpc_driver);
1558 }
1559 module_exit(fastrpc_exit);
1560 
1561 MODULE_LICENSE("GPL v2");
1562