xref: /openbmc/linux/drivers/tee/optee/ffa_abi.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2021, Linaro Limited
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/arm_ffa.h>
9 #include <linux/errno.h>
10 #include <linux/scatterlist.h>
11 #include <linux/sched.h>
12 #include <linux/slab.h>
13 #include <linux/string.h>
14 #include <linux/tee_drv.h>
15 #include <linux/types.h>
16 #include "optee_private.h"
17 #include "optee_ffa.h"
18 #include "optee_rpc_cmd.h"
19 
20 /*
21  * This file implement the FF-A ABI used when communicating with secure world
22  * OP-TEE OS via FF-A.
23  * This file is divided into the following sections:
24  * 1. Maintain a hash table for lookup of a global FF-A memory handle
25  * 2. Convert between struct tee_param and struct optee_msg_param
26  * 3. Low level support functions to register shared memory in secure world
27  * 4. Dynamic shared memory pool based on alloc_pages()
28  * 5. Do a normal scheduled call into secure world
29  * 6. Driver initialization.
30  */
31 
32 /*
33  * 1. Maintain a hash table for lookup of a global FF-A memory handle
34  *
35  * FF-A assigns a global memory handle for each piece shared memory.
36  * This handle is then used when communicating with secure world.
37  *
38  * Main functions are optee_shm_add_ffa_handle() and optee_shm_rem_ffa_handle()
39  */
40 struct shm_rhash {
41 	struct tee_shm *shm;
42 	u64 global_id;
43 	struct rhash_head linkage;
44 };
45 
46 static void rh_free_fn(void *ptr, void *arg)
47 {
48 	kfree(ptr);
49 }
50 
51 static const struct rhashtable_params shm_rhash_params = {
52 	.head_offset = offsetof(struct shm_rhash, linkage),
53 	.key_len     = sizeof(u64),
54 	.key_offset  = offsetof(struct shm_rhash, global_id),
55 	.automatic_shrinking = true,
56 };
57 
58 static struct tee_shm *optee_shm_from_ffa_handle(struct optee *optee,
59 						 u64 global_id)
60 {
61 	struct tee_shm *shm = NULL;
62 	struct shm_rhash *r;
63 
64 	mutex_lock(&optee->ffa.mutex);
65 	r = rhashtable_lookup_fast(&optee->ffa.global_ids, &global_id,
66 				   shm_rhash_params);
67 	if (r)
68 		shm = r->shm;
69 	mutex_unlock(&optee->ffa.mutex);
70 
71 	return shm;
72 }
73 
74 static int optee_shm_add_ffa_handle(struct optee *optee, struct tee_shm *shm,
75 				    u64 global_id)
76 {
77 	struct shm_rhash *r;
78 	int rc;
79 
80 	r = kmalloc(sizeof(*r), GFP_KERNEL);
81 	if (!r)
82 		return -ENOMEM;
83 	r->shm = shm;
84 	r->global_id = global_id;
85 
86 	mutex_lock(&optee->ffa.mutex);
87 	rc = rhashtable_lookup_insert_fast(&optee->ffa.global_ids, &r->linkage,
88 					   shm_rhash_params);
89 	mutex_unlock(&optee->ffa.mutex);
90 
91 	if (rc)
92 		kfree(r);
93 
94 	return rc;
95 }
96 
97 static int optee_shm_rem_ffa_handle(struct optee *optee, u64 global_id)
98 {
99 	struct shm_rhash *r;
100 	int rc = -ENOENT;
101 
102 	mutex_lock(&optee->ffa.mutex);
103 	r = rhashtable_lookup_fast(&optee->ffa.global_ids, &global_id,
104 				   shm_rhash_params);
105 	if (r)
106 		rc = rhashtable_remove_fast(&optee->ffa.global_ids,
107 					    &r->linkage, shm_rhash_params);
108 	mutex_unlock(&optee->ffa.mutex);
109 
110 	if (!rc)
111 		kfree(r);
112 
113 	return rc;
114 }
115 
116 /*
117  * 2. Convert between struct tee_param and struct optee_msg_param
118  *
119  * optee_ffa_from_msg_param() and optee_ffa_to_msg_param() are the main
120  * functions.
121  */
122 
123 static void from_msg_param_ffa_mem(struct optee *optee, struct tee_param *p,
124 				   u32 attr, const struct optee_msg_param *mp)
125 {
126 	struct tee_shm *shm = NULL;
127 	u64 offs_high = 0;
128 	u64 offs_low = 0;
129 
130 	p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
131 		  attr - OPTEE_MSG_ATTR_TYPE_FMEM_INPUT;
132 	p->u.memref.size = mp->u.fmem.size;
133 
134 	if (mp->u.fmem.global_id != OPTEE_MSG_FMEM_INVALID_GLOBAL_ID)
135 		shm = optee_shm_from_ffa_handle(optee, mp->u.fmem.global_id);
136 	p->u.memref.shm = shm;
137 
138 	if (shm) {
139 		offs_low = mp->u.fmem.offs_low;
140 		offs_high = mp->u.fmem.offs_high;
141 	}
142 	p->u.memref.shm_offs = offs_low | offs_high << 32;
143 }
144 
145 /**
146  * optee_ffa_from_msg_param() - convert from OPTEE_MSG parameters to
147  *				struct tee_param
148  * @optee:	main service struct
149  * @params:	subsystem internal parameter representation
150  * @num_params:	number of elements in the parameter arrays
151  * @msg_params:	OPTEE_MSG parameters
152  *
153  * Returns 0 on success or <0 on failure
154  */
155 static int optee_ffa_from_msg_param(struct optee *optee,
156 				    struct tee_param *params, size_t num_params,
157 				    const struct optee_msg_param *msg_params)
158 {
159 	size_t n;
160 
161 	for (n = 0; n < num_params; n++) {
162 		struct tee_param *p = params + n;
163 		const struct optee_msg_param *mp = msg_params + n;
164 		u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK;
165 
166 		switch (attr) {
167 		case OPTEE_MSG_ATTR_TYPE_NONE:
168 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
169 			memset(&p->u, 0, sizeof(p->u));
170 			break;
171 		case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT:
172 		case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT:
173 		case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT:
174 			optee_from_msg_param_value(p, attr, mp);
175 			break;
176 		case OPTEE_MSG_ATTR_TYPE_FMEM_INPUT:
177 		case OPTEE_MSG_ATTR_TYPE_FMEM_OUTPUT:
178 		case OPTEE_MSG_ATTR_TYPE_FMEM_INOUT:
179 			from_msg_param_ffa_mem(optee, p, attr, mp);
180 			break;
181 		default:
182 			return -EINVAL;
183 		}
184 	}
185 
186 	return 0;
187 }
188 
189 static int to_msg_param_ffa_mem(struct optee_msg_param *mp,
190 				const struct tee_param *p)
191 {
192 	struct tee_shm *shm = p->u.memref.shm;
193 
194 	mp->attr = OPTEE_MSG_ATTR_TYPE_FMEM_INPUT + p->attr -
195 		   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
196 
197 	if (shm) {
198 		u64 shm_offs = p->u.memref.shm_offs;
199 
200 		mp->u.fmem.internal_offs = shm->offset;
201 
202 		mp->u.fmem.offs_low = shm_offs;
203 		mp->u.fmem.offs_high = shm_offs >> 32;
204 		/* Check that the entire offset could be stored. */
205 		if (mp->u.fmem.offs_high != shm_offs >> 32)
206 			return -EINVAL;
207 
208 		mp->u.fmem.global_id = shm->sec_world_id;
209 	} else {
210 		memset(&mp->u, 0, sizeof(mp->u));
211 		mp->u.fmem.global_id = OPTEE_MSG_FMEM_INVALID_GLOBAL_ID;
212 	}
213 	mp->u.fmem.size = p->u.memref.size;
214 
215 	return 0;
216 }
217 
218 /**
219  * optee_ffa_to_msg_param() - convert from struct tee_params to OPTEE_MSG
220  *			      parameters
221  * @optee:	main service struct
222  * @msg_params:	OPTEE_MSG parameters
223  * @num_params:	number of elements in the parameter arrays
224  * @params:	subsystem itnernal parameter representation
225  * Returns 0 on success or <0 on failure
226  */
227 static int optee_ffa_to_msg_param(struct optee *optee,
228 				  struct optee_msg_param *msg_params,
229 				  size_t num_params,
230 				  const struct tee_param *params)
231 {
232 	size_t n;
233 
234 	for (n = 0; n < num_params; n++) {
235 		const struct tee_param *p = params + n;
236 		struct optee_msg_param *mp = msg_params + n;
237 
238 		switch (p->attr) {
239 		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
240 			mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
241 			memset(&mp->u, 0, sizeof(mp->u));
242 			break;
243 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
244 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
245 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
246 			optee_to_msg_param_value(mp, p);
247 			break;
248 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
249 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
250 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
251 			if (to_msg_param_ffa_mem(mp, p))
252 				return -EINVAL;
253 			break;
254 		default:
255 			return -EINVAL;
256 		}
257 	}
258 
259 	return 0;
260 }
261 
262 /*
263  * 3. Low level support functions to register shared memory in secure world
264  *
265  * Functions to register and unregister shared memory both for normal
266  * clients and for tee-supplicant.
267  */
268 
269 static int optee_ffa_shm_register(struct tee_context *ctx, struct tee_shm *shm,
270 				  struct page **pages, size_t num_pages,
271 				  unsigned long start)
272 {
273 	struct optee *optee = tee_get_drvdata(ctx->teedev);
274 	const struct ffa_dev_ops *ffa_ops = optee->ffa.ffa_ops;
275 	struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
276 	struct ffa_mem_region_attributes mem_attr = {
277 		.receiver = ffa_dev->vm_id,
278 		.attrs = FFA_MEM_RW,
279 	};
280 	struct ffa_mem_ops_args args = {
281 		.use_txbuf = true,
282 		.attrs = &mem_attr,
283 		.nattrs = 1,
284 	};
285 	struct sg_table sgt;
286 	int rc;
287 
288 	rc = optee_check_mem_type(start, num_pages);
289 	if (rc)
290 		return rc;
291 
292 	rc = sg_alloc_table_from_pages(&sgt, pages, num_pages, 0,
293 				       num_pages * PAGE_SIZE, GFP_KERNEL);
294 	if (rc)
295 		return rc;
296 	args.sg = sgt.sgl;
297 	rc = ffa_ops->memory_share(ffa_dev, &args);
298 	sg_free_table(&sgt);
299 	if (rc)
300 		return rc;
301 
302 	rc = optee_shm_add_ffa_handle(optee, shm, args.g_handle);
303 	if (rc) {
304 		ffa_ops->memory_reclaim(args.g_handle, 0);
305 		return rc;
306 	}
307 
308 	shm->sec_world_id = args.g_handle;
309 
310 	return 0;
311 }
312 
313 static int optee_ffa_shm_unregister(struct tee_context *ctx,
314 				    struct tee_shm *shm)
315 {
316 	struct optee *optee = tee_get_drvdata(ctx->teedev);
317 	const struct ffa_dev_ops *ffa_ops = optee->ffa.ffa_ops;
318 	struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
319 	u64 global_handle = shm->sec_world_id;
320 	struct ffa_send_direct_data data = {
321 		.data0 = OPTEE_FFA_UNREGISTER_SHM,
322 		.data1 = (u32)global_handle,
323 		.data2 = (u32)(global_handle >> 32)
324 	};
325 	int rc;
326 
327 	optee_shm_rem_ffa_handle(optee, global_handle);
328 	shm->sec_world_id = 0;
329 
330 	rc = ffa_ops->sync_send_receive(ffa_dev, &data);
331 	if (rc)
332 		pr_err("Unregister SHM id 0x%llx rc %d\n", global_handle, rc);
333 
334 	rc = ffa_ops->memory_reclaim(global_handle, 0);
335 	if (rc)
336 		pr_err("mem_reclaim: 0x%llx %d", global_handle, rc);
337 
338 	return rc;
339 }
340 
341 static int optee_ffa_shm_unregister_supp(struct tee_context *ctx,
342 					 struct tee_shm *shm)
343 {
344 	struct optee *optee = tee_get_drvdata(ctx->teedev);
345 	const struct ffa_dev_ops *ffa_ops = optee->ffa.ffa_ops;
346 	u64 global_handle = shm->sec_world_id;
347 	int rc;
348 
349 	/*
350 	 * We're skipping the OPTEE_FFA_YIELDING_CALL_UNREGISTER_SHM call
351 	 * since this is OP-TEE freeing via RPC so it has already retired
352 	 * this ID.
353 	 */
354 
355 	optee_shm_rem_ffa_handle(optee, global_handle);
356 	rc = ffa_ops->memory_reclaim(global_handle, 0);
357 	if (rc)
358 		pr_err("mem_reclaim: 0x%llx %d", global_handle, rc);
359 
360 	shm->sec_world_id = 0;
361 
362 	return rc;
363 }
364 
365 /*
366  * 4. Dynamic shared memory pool based on alloc_pages()
367  *
368  * Implements an OP-TEE specific shared memory pool.
369  * The main function is optee_ffa_shm_pool_alloc_pages().
370  */
371 
372 static int pool_ffa_op_alloc(struct tee_shm_pool_mgr *poolm,
373 			     struct tee_shm *shm, size_t size)
374 {
375 	return optee_pool_op_alloc_helper(poolm, shm, size,
376 					  optee_ffa_shm_register);
377 }
378 
379 static void pool_ffa_op_free(struct tee_shm_pool_mgr *poolm,
380 			     struct tee_shm *shm)
381 {
382 	optee_ffa_shm_unregister(shm->ctx, shm);
383 	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
384 	shm->kaddr = NULL;
385 }
386 
387 static void pool_ffa_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
388 {
389 	kfree(poolm);
390 }
391 
392 static const struct tee_shm_pool_mgr_ops pool_ffa_ops = {
393 	.alloc = pool_ffa_op_alloc,
394 	.free = pool_ffa_op_free,
395 	.destroy_poolmgr = pool_ffa_op_destroy_poolmgr,
396 };
397 
398 /**
399  * optee_ffa_shm_pool_alloc_pages() - create page-based allocator pool
400  *
401  * This pool is used with OP-TEE over FF-A. In this case command buffers
402  * and such are allocated from kernel's own memory.
403  */
404 static struct tee_shm_pool_mgr *optee_ffa_shm_pool_alloc_pages(void)
405 {
406 	struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
407 
408 	if (!mgr)
409 		return ERR_PTR(-ENOMEM);
410 
411 	mgr->ops = &pool_ffa_ops;
412 
413 	return mgr;
414 }
415 
416 /*
417  * 5. Do a normal scheduled call into secure world
418  *
419  * The function optee_ffa_do_call_with_arg() performs a normal scheduled
420  * call into secure world. During this call may normal world request help
421  * from normal world using RPCs, Remote Procedure Calls. This includes
422  * delivery of non-secure interrupts to for instance allow rescheduling of
423  * the current task.
424  */
425 
426 static void handle_ffa_rpc_func_cmd_shm_alloc(struct tee_context *ctx,
427 					      struct optee_msg_arg *arg)
428 {
429 	struct tee_shm *shm;
430 
431 	if (arg->num_params != 1 ||
432 	    arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT) {
433 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
434 		return;
435 	}
436 
437 	switch (arg->params[0].u.value.a) {
438 	case OPTEE_RPC_SHM_TYPE_APPL:
439 		shm = optee_rpc_cmd_alloc_suppl(ctx, arg->params[0].u.value.b);
440 		break;
441 	case OPTEE_RPC_SHM_TYPE_KERNEL:
442 		shm = tee_shm_alloc(ctx, arg->params[0].u.value.b,
443 				    TEE_SHM_MAPPED | TEE_SHM_PRIV);
444 		break;
445 	default:
446 		arg->ret = TEEC_ERROR_BAD_PARAMETERS;
447 		return;
448 	}
449 
450 	if (IS_ERR(shm)) {
451 		arg->ret = TEEC_ERROR_OUT_OF_MEMORY;
452 		return;
453 	}
454 
455 	arg->params[0] = (struct optee_msg_param){
456 		.attr = OPTEE_MSG_ATTR_TYPE_FMEM_OUTPUT,
457 		.u.fmem.size = tee_shm_get_size(shm),
458 		.u.fmem.global_id = shm->sec_world_id,
459 		.u.fmem.internal_offs = shm->offset,
460 	};
461 
462 	arg->ret = TEEC_SUCCESS;
463 }
464 
465 static void handle_ffa_rpc_func_cmd_shm_free(struct tee_context *ctx,
466 					     struct optee *optee,
467 					     struct optee_msg_arg *arg)
468 {
469 	struct tee_shm *shm;
470 
471 	if (arg->num_params != 1 ||
472 	    arg->params[0].attr != OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
473 		goto err_bad_param;
474 
475 	shm = optee_shm_from_ffa_handle(optee, arg->params[0].u.value.b);
476 	if (!shm)
477 		goto err_bad_param;
478 	switch (arg->params[0].u.value.a) {
479 	case OPTEE_RPC_SHM_TYPE_APPL:
480 		optee_rpc_cmd_free_suppl(ctx, shm);
481 		break;
482 	case OPTEE_RPC_SHM_TYPE_KERNEL:
483 		tee_shm_free(shm);
484 		break;
485 	default:
486 		goto err_bad_param;
487 	}
488 	arg->ret = TEEC_SUCCESS;
489 	return;
490 
491 err_bad_param:
492 	arg->ret = TEEC_ERROR_BAD_PARAMETERS;
493 }
494 
495 static void handle_ffa_rpc_func_cmd(struct tee_context *ctx,
496 				    struct optee_msg_arg *arg)
497 {
498 	struct optee *optee = tee_get_drvdata(ctx->teedev);
499 
500 	arg->ret_origin = TEEC_ORIGIN_COMMS;
501 	switch (arg->cmd) {
502 	case OPTEE_RPC_CMD_SHM_ALLOC:
503 		handle_ffa_rpc_func_cmd_shm_alloc(ctx, arg);
504 		break;
505 	case OPTEE_RPC_CMD_SHM_FREE:
506 		handle_ffa_rpc_func_cmd_shm_free(ctx, optee, arg);
507 		break;
508 	default:
509 		optee_rpc_cmd(ctx, optee, arg);
510 	}
511 }
512 
513 static void optee_handle_ffa_rpc(struct tee_context *ctx, u32 cmd,
514 				 struct optee_msg_arg *arg)
515 {
516 	switch (cmd) {
517 	case OPTEE_FFA_YIELDING_CALL_RETURN_RPC_CMD:
518 		handle_ffa_rpc_func_cmd(ctx, arg);
519 		break;
520 	case OPTEE_FFA_YIELDING_CALL_RETURN_INTERRUPT:
521 		/* Interrupt delivered by now */
522 		break;
523 	default:
524 		pr_warn("Unknown RPC func 0x%x\n", cmd);
525 		break;
526 	}
527 }
528 
529 static int optee_ffa_yielding_call(struct tee_context *ctx,
530 				   struct ffa_send_direct_data *data,
531 				   struct optee_msg_arg *rpc_arg)
532 {
533 	struct optee *optee = tee_get_drvdata(ctx->teedev);
534 	const struct ffa_dev_ops *ffa_ops = optee->ffa.ffa_ops;
535 	struct ffa_device *ffa_dev = optee->ffa.ffa_dev;
536 	struct optee_call_waiter w;
537 	u32 cmd = data->data0;
538 	u32 w4 = data->data1;
539 	u32 w5 = data->data2;
540 	u32 w6 = data->data3;
541 	int rc;
542 
543 	/* Initialize waiter */
544 	optee_cq_wait_init(&optee->call_queue, &w);
545 	while (true) {
546 		rc = ffa_ops->sync_send_receive(ffa_dev, data);
547 		if (rc)
548 			goto done;
549 
550 		switch ((int)data->data0) {
551 		case TEEC_SUCCESS:
552 			break;
553 		case TEEC_ERROR_BUSY:
554 			if (cmd == OPTEE_FFA_YIELDING_CALL_RESUME) {
555 				rc = -EIO;
556 				goto done;
557 			}
558 
559 			/*
560 			 * Out of threads in secure world, wait for a thread
561 			 * become available.
562 			 */
563 			optee_cq_wait_for_completion(&optee->call_queue, &w);
564 			data->data0 = cmd;
565 			data->data1 = w4;
566 			data->data2 = w5;
567 			data->data3 = w6;
568 			continue;
569 		default:
570 			rc = -EIO;
571 			goto done;
572 		}
573 
574 		if (data->data1 == OPTEE_FFA_YIELDING_CALL_RETURN_DONE)
575 			goto done;
576 
577 		/*
578 		 * OP-TEE has returned with a RPC request.
579 		 *
580 		 * Note that data->data4 (passed in register w7) is already
581 		 * filled in by ffa_ops->sync_send_receive() returning
582 		 * above.
583 		 */
584 		cond_resched();
585 		optee_handle_ffa_rpc(ctx, data->data1, rpc_arg);
586 		cmd = OPTEE_FFA_YIELDING_CALL_RESUME;
587 		data->data0 = cmd;
588 		data->data1 = 0;
589 		data->data2 = 0;
590 		data->data3 = 0;
591 	}
592 done:
593 	/*
594 	 * We're done with our thread in secure world, if there's any
595 	 * thread waiters wake up one.
596 	 */
597 	optee_cq_wait_final(&optee->call_queue, &w);
598 
599 	return rc;
600 }
601 
602 /**
603  * optee_ffa_do_call_with_arg() - Do a FF-A call to enter OP-TEE in secure world
604  * @ctx:	calling context
605  * @shm:	shared memory holding the message to pass to secure world
606  *
607  * Does a FF-A call to OP-TEE in secure world and handles eventual resulting
608  * Remote Procedure Calls (RPC) from OP-TEE.
609  *
610  * Returns return code from FF-A, 0 is OK
611  */
612 
613 static int optee_ffa_do_call_with_arg(struct tee_context *ctx,
614 				      struct tee_shm *shm)
615 {
616 	struct ffa_send_direct_data data = {
617 		.data0 = OPTEE_FFA_YIELDING_CALL_WITH_ARG,
618 		.data1 = (u32)shm->sec_world_id,
619 		.data2 = (u32)(shm->sec_world_id >> 32),
620 		.data3 = shm->offset,
621 	};
622 	struct optee_msg_arg *arg = tee_shm_get_va(shm, 0);
623 	unsigned int rpc_arg_offs = OPTEE_MSG_GET_ARG_SIZE(arg->num_params);
624 	struct optee_msg_arg *rpc_arg = tee_shm_get_va(shm, rpc_arg_offs);
625 
626 	return optee_ffa_yielding_call(ctx, &data, rpc_arg);
627 }
628 
629 /*
630  * 6. Driver initialization
631  *
632  * During driver inititialization is the OP-TEE Secure Partition is probed
633  * to find out which features it supports so the driver can be initialized
634  * with a matching configuration.
635  */
636 
637 static bool optee_ffa_api_is_compatbile(struct ffa_device *ffa_dev,
638 					const struct ffa_dev_ops *ops)
639 {
640 	struct ffa_send_direct_data data = { OPTEE_FFA_GET_API_VERSION };
641 	int rc;
642 
643 	ops->mode_32bit_set(ffa_dev);
644 
645 	rc = ops->sync_send_receive(ffa_dev, &data);
646 	if (rc) {
647 		pr_err("Unexpected error %d\n", rc);
648 		return false;
649 	}
650 	if (data.data0 != OPTEE_FFA_VERSION_MAJOR ||
651 	    data.data1 < OPTEE_FFA_VERSION_MINOR) {
652 		pr_err("Incompatible OP-TEE API version %lu.%lu",
653 		       data.data0, data.data1);
654 		return false;
655 	}
656 
657 	data = (struct ffa_send_direct_data){ OPTEE_FFA_GET_OS_VERSION };
658 	rc = ops->sync_send_receive(ffa_dev, &data);
659 	if (rc) {
660 		pr_err("Unexpected error %d\n", rc);
661 		return false;
662 	}
663 	if (data.data2)
664 		pr_info("revision %lu.%lu (%08lx)",
665 			data.data0, data.data1, data.data2);
666 	else
667 		pr_info("revision %lu.%lu", data.data0, data.data1);
668 
669 	return true;
670 }
671 
672 static bool optee_ffa_exchange_caps(struct ffa_device *ffa_dev,
673 				    const struct ffa_dev_ops *ops,
674 				    unsigned int *rpc_arg_count)
675 {
676 	struct ffa_send_direct_data data = { OPTEE_FFA_EXCHANGE_CAPABILITIES };
677 	int rc;
678 
679 	rc = ops->sync_send_receive(ffa_dev, &data);
680 	if (rc) {
681 		pr_err("Unexpected error %d", rc);
682 		return false;
683 	}
684 	if (data.data0) {
685 		pr_err("Unexpected exchange error %lu", data.data0);
686 		return false;
687 	}
688 
689 	*rpc_arg_count = (u8)data.data1;
690 
691 	return true;
692 }
693 
694 static struct tee_shm_pool *optee_ffa_config_dyn_shm(void)
695 {
696 	struct tee_shm_pool_mgr *priv_mgr;
697 	struct tee_shm_pool_mgr *dmabuf_mgr;
698 	void *rc;
699 
700 	rc = optee_ffa_shm_pool_alloc_pages();
701 	if (IS_ERR(rc))
702 		return rc;
703 	priv_mgr = rc;
704 
705 	rc = optee_ffa_shm_pool_alloc_pages();
706 	if (IS_ERR(rc)) {
707 		tee_shm_pool_mgr_destroy(priv_mgr);
708 		return rc;
709 	}
710 	dmabuf_mgr = rc;
711 
712 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
713 	if (IS_ERR(rc)) {
714 		tee_shm_pool_mgr_destroy(priv_mgr);
715 		tee_shm_pool_mgr_destroy(dmabuf_mgr);
716 	}
717 
718 	return rc;
719 }
720 
721 static void optee_ffa_get_version(struct tee_device *teedev,
722 				  struct tee_ioctl_version_data *vers)
723 {
724 	struct tee_ioctl_version_data v = {
725 		.impl_id = TEE_IMPL_ID_OPTEE,
726 		.impl_caps = TEE_OPTEE_CAP_TZ,
727 		.gen_caps = TEE_GEN_CAP_GP | TEE_GEN_CAP_REG_MEM |
728 			    TEE_GEN_CAP_MEMREF_NULL,
729 	};
730 
731 	*vers = v;
732 }
733 
734 static int optee_ffa_open(struct tee_context *ctx)
735 {
736 	return optee_open(ctx, true);
737 }
738 
739 static const struct tee_driver_ops optee_ffa_clnt_ops = {
740 	.get_version = optee_ffa_get_version,
741 	.open = optee_ffa_open,
742 	.release = optee_release,
743 	.open_session = optee_open_session,
744 	.close_session = optee_close_session,
745 	.invoke_func = optee_invoke_func,
746 	.cancel_req = optee_cancel_req,
747 	.shm_register = optee_ffa_shm_register,
748 	.shm_unregister = optee_ffa_shm_unregister,
749 };
750 
751 static const struct tee_desc optee_ffa_clnt_desc = {
752 	.name = DRIVER_NAME "-ffa-clnt",
753 	.ops = &optee_ffa_clnt_ops,
754 	.owner = THIS_MODULE,
755 };
756 
757 static const struct tee_driver_ops optee_ffa_supp_ops = {
758 	.get_version = optee_ffa_get_version,
759 	.open = optee_ffa_open,
760 	.release = optee_release_supp,
761 	.supp_recv = optee_supp_recv,
762 	.supp_send = optee_supp_send,
763 	.shm_register = optee_ffa_shm_register, /* same as for clnt ops */
764 	.shm_unregister = optee_ffa_shm_unregister_supp,
765 };
766 
767 static const struct tee_desc optee_ffa_supp_desc = {
768 	.name = DRIVER_NAME "-ffa-supp",
769 	.ops = &optee_ffa_supp_ops,
770 	.owner = THIS_MODULE,
771 	.flags = TEE_DESC_PRIVILEGED,
772 };
773 
774 static const struct optee_ops optee_ffa_ops = {
775 	.do_call_with_arg = optee_ffa_do_call_with_arg,
776 	.to_msg_param = optee_ffa_to_msg_param,
777 	.from_msg_param = optee_ffa_from_msg_param,
778 };
779 
780 static void optee_ffa_remove(struct ffa_device *ffa_dev)
781 {
782 	struct optee *optee = ffa_dev->dev.driver_data;
783 
784 	optee_remove_common(optee);
785 
786 	mutex_destroy(&optee->ffa.mutex);
787 	rhashtable_free_and_destroy(&optee->ffa.global_ids, rh_free_fn, NULL);
788 
789 	kfree(optee);
790 }
791 
792 static int optee_ffa_probe(struct ffa_device *ffa_dev)
793 {
794 	const struct ffa_dev_ops *ffa_ops;
795 	unsigned int rpc_arg_count;
796 	struct tee_device *teedev;
797 	struct optee *optee;
798 	int rc;
799 
800 	ffa_ops = ffa_dev_ops_get(ffa_dev);
801 	if (!ffa_ops) {
802 		pr_warn("failed \"method\" init: ffa\n");
803 		return -ENOENT;
804 	}
805 
806 	if (!optee_ffa_api_is_compatbile(ffa_dev, ffa_ops))
807 		return -EINVAL;
808 
809 	if (!optee_ffa_exchange_caps(ffa_dev, ffa_ops, &rpc_arg_count))
810 		return -EINVAL;
811 
812 	optee = kzalloc(sizeof(*optee), GFP_KERNEL);
813 	if (!optee) {
814 		rc = -ENOMEM;
815 		goto err;
816 	}
817 	optee->pool = optee_ffa_config_dyn_shm();
818 	if (IS_ERR(optee->pool)) {
819 		rc = PTR_ERR(optee->pool);
820 		optee->pool = NULL;
821 		goto err;
822 	}
823 
824 	optee->ops = &optee_ffa_ops;
825 	optee->ffa.ffa_dev = ffa_dev;
826 	optee->ffa.ffa_ops = ffa_ops;
827 	optee->rpc_arg_count = rpc_arg_count;
828 
829 	teedev = tee_device_alloc(&optee_ffa_clnt_desc, NULL, optee->pool,
830 				  optee);
831 	if (IS_ERR(teedev)) {
832 		rc = PTR_ERR(teedev);
833 		goto err;
834 	}
835 	optee->teedev = teedev;
836 
837 	teedev = tee_device_alloc(&optee_ffa_supp_desc, NULL, optee->pool,
838 				  optee);
839 	if (IS_ERR(teedev)) {
840 		rc = PTR_ERR(teedev);
841 		goto err;
842 	}
843 	optee->supp_teedev = teedev;
844 
845 	rc = tee_device_register(optee->teedev);
846 	if (rc)
847 		goto err;
848 
849 	rc = tee_device_register(optee->supp_teedev);
850 	if (rc)
851 		goto err;
852 
853 	rc = rhashtable_init(&optee->ffa.global_ids, &shm_rhash_params);
854 	if (rc)
855 		goto err;
856 	mutex_init(&optee->ffa.mutex);
857 	mutex_init(&optee->call_queue.mutex);
858 	INIT_LIST_HEAD(&optee->call_queue.waiters);
859 	optee_wait_queue_init(&optee->wait_queue);
860 	optee_supp_init(&optee->supp);
861 	ffa_dev_set_drvdata(ffa_dev, optee);
862 
863 	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
864 	if (rc) {
865 		optee_ffa_remove(ffa_dev);
866 		return rc;
867 	}
868 
869 	pr_info("initialized driver\n");
870 	return 0;
871 err:
872 	/*
873 	 * tee_device_unregister() is safe to call even if the
874 	 * devices hasn't been registered with
875 	 * tee_device_register() yet.
876 	 */
877 	tee_device_unregister(optee->supp_teedev);
878 	tee_device_unregister(optee->teedev);
879 	if (optee->pool)
880 		tee_shm_pool_free(optee->pool);
881 	kfree(optee);
882 	return rc;
883 }
884 
885 static const struct ffa_device_id optee_ffa_device_id[] = {
886 	/* 486178e0-e7f8-11e3-bc5e0002a5d5c51b */
887 	{ UUID_INIT(0x486178e0, 0xe7f8, 0x11e3,
888 		    0xbc, 0x5e, 0x00, 0x02, 0xa5, 0xd5, 0xc5, 0x1b) },
889 	{}
890 };
891 
892 static struct ffa_driver optee_ffa_driver = {
893 	.name = "optee",
894 	.probe = optee_ffa_probe,
895 	.remove = optee_ffa_remove,
896 	.id_table = optee_ffa_device_id,
897 };
898 
899 int optee_ffa_abi_register(void)
900 {
901 	if (IS_REACHABLE(CONFIG_ARM_FFA_TRANSPORT))
902 		return ffa_register(&optee_ffa_driver);
903 	else
904 		return -EOPNOTSUPP;
905 }
906 
907 void optee_ffa_abi_unregister(void)
908 {
909 	if (IS_REACHABLE(CONFIG_ARM_FFA_TRANSPORT))
910 		ffa_unregister(&optee_ffa_driver);
911 }
912