xref: /linux/drivers/tee/optee/core.c (revision 9a6b55ac)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/arm-smccc.h>
9 #include <linux/errno.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/tee_drv.h>
18 #include <linux/types.h>
19 #include <linux/uaccess.h>
20 #include "optee_private.h"
21 #include "optee_smc.h"
22 #include "shm_pool.h"
23 
24 #define DRIVER_NAME "optee"
25 
26 #define OPTEE_SHM_NUM_PRIV_PAGES	CONFIG_OPTEE_SHM_NUM_PRIV_PAGES
27 
28 /**
29  * optee_from_msg_param() - convert from OPTEE_MSG parameters to
30  *			    struct tee_param
31  * @params:	subsystem internal parameter representation
32  * @num_params:	number of elements in the parameter arrays
33  * @msg_params:	OPTEE_MSG parameters
34  * Returns 0 on success or <0 on failure
35  */
36 int optee_from_msg_param(struct tee_param *params, size_t num_params,
37 			 const struct optee_msg_param *msg_params)
38 {
39 	int rc;
40 	size_t n;
41 	struct tee_shm *shm;
42 	phys_addr_t pa;
43 
44 	for (n = 0; n < num_params; n++) {
45 		struct tee_param *p = params + n;
46 		const struct optee_msg_param *mp = msg_params + n;
47 		u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK;
48 
49 		switch (attr) {
50 		case OPTEE_MSG_ATTR_TYPE_NONE:
51 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
52 			memset(&p->u, 0, sizeof(p->u));
53 			break;
54 		case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT:
55 		case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT:
56 		case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT:
57 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT +
58 				  attr - OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
59 			p->u.value.a = mp->u.value.a;
60 			p->u.value.b = mp->u.value.b;
61 			p->u.value.c = mp->u.value.c;
62 			break;
63 		case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT:
64 		case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT:
65 		case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT:
66 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
67 				  attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT;
68 			p->u.memref.size = mp->u.tmem.size;
69 			shm = (struct tee_shm *)(unsigned long)
70 				mp->u.tmem.shm_ref;
71 			if (!shm) {
72 				p->u.memref.shm_offs = 0;
73 				p->u.memref.shm = NULL;
74 				break;
75 			}
76 			rc = tee_shm_get_pa(shm, 0, &pa);
77 			if (rc)
78 				return rc;
79 			p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa;
80 			p->u.memref.shm = shm;
81 
82 			/* Check that the memref is covered by the shm object */
83 			if (p->u.memref.size) {
84 				size_t o = p->u.memref.shm_offs +
85 					   p->u.memref.size - 1;
86 
87 				rc = tee_shm_get_pa(shm, o, NULL);
88 				if (rc)
89 					return rc;
90 			}
91 			break;
92 		case OPTEE_MSG_ATTR_TYPE_RMEM_INPUT:
93 		case OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT:
94 		case OPTEE_MSG_ATTR_TYPE_RMEM_INOUT:
95 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
96 				  attr - OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
97 			p->u.memref.size = mp->u.rmem.size;
98 			shm = (struct tee_shm *)(unsigned long)
99 				mp->u.rmem.shm_ref;
100 
101 			if (!shm) {
102 				p->u.memref.shm_offs = 0;
103 				p->u.memref.shm = NULL;
104 				break;
105 			}
106 			p->u.memref.shm_offs = mp->u.rmem.offs;
107 			p->u.memref.shm = shm;
108 
109 			break;
110 
111 		default:
112 			return -EINVAL;
113 		}
114 	}
115 	return 0;
116 }
117 
118 static int to_msg_param_tmp_mem(struct optee_msg_param *mp,
119 				const struct tee_param *p)
120 {
121 	int rc;
122 	phys_addr_t pa;
123 
124 	mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT + p->attr -
125 		   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
126 
127 	mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm;
128 	mp->u.tmem.size = p->u.memref.size;
129 
130 	if (!p->u.memref.shm) {
131 		mp->u.tmem.buf_ptr = 0;
132 		return 0;
133 	}
134 
135 	rc = tee_shm_get_pa(p->u.memref.shm, p->u.memref.shm_offs, &pa);
136 	if (rc)
137 		return rc;
138 
139 	mp->u.tmem.buf_ptr = pa;
140 	mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED <<
141 		    OPTEE_MSG_ATTR_CACHE_SHIFT;
142 
143 	return 0;
144 }
145 
146 static int to_msg_param_reg_mem(struct optee_msg_param *mp,
147 				const struct tee_param *p)
148 {
149 	mp->attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT + p->attr -
150 		   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
151 
152 	mp->u.rmem.shm_ref = (unsigned long)p->u.memref.shm;
153 	mp->u.rmem.size = p->u.memref.size;
154 	mp->u.rmem.offs = p->u.memref.shm_offs;
155 	return 0;
156 }
157 
158 /**
159  * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters
160  * @msg_params:	OPTEE_MSG parameters
161  * @num_params:	number of elements in the parameter arrays
162  * @params:	subsystem itnernal parameter representation
163  * Returns 0 on success or <0 on failure
164  */
165 int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params,
166 		       const struct tee_param *params)
167 {
168 	int rc;
169 	size_t n;
170 
171 	for (n = 0; n < num_params; n++) {
172 		const struct tee_param *p = params + n;
173 		struct optee_msg_param *mp = msg_params + n;
174 
175 		switch (p->attr) {
176 		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
177 			mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
178 			memset(&mp->u, 0, sizeof(mp->u));
179 			break;
180 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
181 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
182 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
183 			mp->attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT + p->attr -
184 				   TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
185 			mp->u.value.a = p->u.value.a;
186 			mp->u.value.b = p->u.value.b;
187 			mp->u.value.c = p->u.value.c;
188 			break;
189 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
190 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
191 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
192 			if (tee_shm_is_registered(p->u.memref.shm))
193 				rc = to_msg_param_reg_mem(mp, p);
194 			else
195 				rc = to_msg_param_tmp_mem(mp, p);
196 			if (rc)
197 				return rc;
198 			break;
199 		default:
200 			return -EINVAL;
201 		}
202 	}
203 	return 0;
204 }
205 
206 static void optee_get_version(struct tee_device *teedev,
207 			      struct tee_ioctl_version_data *vers)
208 {
209 	struct tee_ioctl_version_data v = {
210 		.impl_id = TEE_IMPL_ID_OPTEE,
211 		.impl_caps = TEE_OPTEE_CAP_TZ,
212 		.gen_caps = TEE_GEN_CAP_GP,
213 	};
214 	struct optee *optee = tee_get_drvdata(teedev);
215 
216 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
217 		v.gen_caps |= TEE_GEN_CAP_REG_MEM;
218 	*vers = v;
219 }
220 
221 static int optee_open(struct tee_context *ctx)
222 {
223 	struct optee_context_data *ctxdata;
224 	struct tee_device *teedev = ctx->teedev;
225 	struct optee *optee = tee_get_drvdata(teedev);
226 
227 	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
228 	if (!ctxdata)
229 		return -ENOMEM;
230 
231 	if (teedev == optee->supp_teedev) {
232 		bool busy = true;
233 
234 		mutex_lock(&optee->supp.mutex);
235 		if (!optee->supp.ctx) {
236 			busy = false;
237 			optee->supp.ctx = ctx;
238 		}
239 		mutex_unlock(&optee->supp.mutex);
240 		if (busy) {
241 			kfree(ctxdata);
242 			return -EBUSY;
243 		}
244 	}
245 
246 	mutex_init(&ctxdata->mutex);
247 	INIT_LIST_HEAD(&ctxdata->sess_list);
248 
249 	ctx->data = ctxdata;
250 	return 0;
251 }
252 
253 static void optee_release(struct tee_context *ctx)
254 {
255 	struct optee_context_data *ctxdata = ctx->data;
256 	struct tee_device *teedev = ctx->teedev;
257 	struct optee *optee = tee_get_drvdata(teedev);
258 	struct tee_shm *shm;
259 	struct optee_msg_arg *arg = NULL;
260 	phys_addr_t parg;
261 	struct optee_session *sess;
262 	struct optee_session *sess_tmp;
263 
264 	if (!ctxdata)
265 		return;
266 
267 	shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED);
268 	if (!IS_ERR(shm)) {
269 		arg = tee_shm_get_va(shm, 0);
270 		/*
271 		 * If va2pa fails for some reason, we can't call into
272 		 * secure world, only free the memory. Secure OS will leak
273 		 * sessions and finally refuse more sessions, but we will
274 		 * at least let normal world reclaim its memory.
275 		 */
276 		if (!IS_ERR(arg))
277 			if (tee_shm_va2pa(shm, arg, &parg))
278 				arg = NULL; /* prevent usage of parg below */
279 	}
280 
281 	list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
282 				 list_node) {
283 		list_del(&sess->list_node);
284 		if (!IS_ERR_OR_NULL(arg)) {
285 			memset(arg, 0, sizeof(*arg));
286 			arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
287 			arg->session = sess->session_id;
288 			optee_do_call_with_arg(ctx, parg);
289 		}
290 		kfree(sess);
291 	}
292 	kfree(ctxdata);
293 
294 	if (!IS_ERR(shm))
295 		tee_shm_free(shm);
296 
297 	ctx->data = NULL;
298 
299 	if (teedev == optee->supp_teedev)
300 		optee_supp_release(&optee->supp);
301 }
302 
303 static const struct tee_driver_ops optee_ops = {
304 	.get_version = optee_get_version,
305 	.open = optee_open,
306 	.release = optee_release,
307 	.open_session = optee_open_session,
308 	.close_session = optee_close_session,
309 	.invoke_func = optee_invoke_func,
310 	.cancel_req = optee_cancel_req,
311 	.shm_register = optee_shm_register,
312 	.shm_unregister = optee_shm_unregister,
313 };
314 
315 static const struct tee_desc optee_desc = {
316 	.name = DRIVER_NAME "-clnt",
317 	.ops = &optee_ops,
318 	.owner = THIS_MODULE,
319 };
320 
321 static const struct tee_driver_ops optee_supp_ops = {
322 	.get_version = optee_get_version,
323 	.open = optee_open,
324 	.release = optee_release,
325 	.supp_recv = optee_supp_recv,
326 	.supp_send = optee_supp_send,
327 	.shm_register = optee_shm_register_supp,
328 	.shm_unregister = optee_shm_unregister_supp,
329 };
330 
331 static const struct tee_desc optee_supp_desc = {
332 	.name = DRIVER_NAME "-supp",
333 	.ops = &optee_supp_ops,
334 	.owner = THIS_MODULE,
335 	.flags = TEE_DESC_PRIVILEGED,
336 };
337 
338 static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
339 {
340 	struct arm_smccc_res res;
341 
342 	invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res);
343 
344 	if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 &&
345 	    res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3)
346 		return true;
347 	return false;
348 }
349 
350 static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn)
351 {
352 	union {
353 		struct arm_smccc_res smccc;
354 		struct optee_smc_call_get_os_revision_result result;
355 	} res = {
356 		.result = {
357 			.build_id = 0
358 		}
359 	};
360 
361 	invoke_fn(OPTEE_SMC_CALL_GET_OS_REVISION, 0, 0, 0, 0, 0, 0, 0,
362 		  &res.smccc);
363 
364 	if (res.result.build_id)
365 		pr_info("revision %lu.%lu (%08lx)", res.result.major,
366 			res.result.minor, res.result.build_id);
367 	else
368 		pr_info("revision %lu.%lu", res.result.major, res.result.minor);
369 }
370 
371 static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
372 {
373 	union {
374 		struct arm_smccc_res smccc;
375 		struct optee_smc_calls_revision_result result;
376 	} res;
377 
378 	invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
379 
380 	if (res.result.major == OPTEE_MSG_REVISION_MAJOR &&
381 	    (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR)
382 		return true;
383 	return false;
384 }
385 
386 static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
387 					    u32 *sec_caps)
388 {
389 	union {
390 		struct arm_smccc_res smccc;
391 		struct optee_smc_exchange_capabilities_result result;
392 	} res;
393 	u32 a1 = 0;
394 
395 	/*
396 	 * TODO This isn't enough to tell if it's UP system (from kernel
397 	 * point of view) or not, is_smp() returns the the information
398 	 * needed, but can't be called directly from here.
399 	 */
400 	if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1)
401 		a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR;
402 
403 	invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0,
404 		  &res.smccc);
405 
406 	if (res.result.status != OPTEE_SMC_RETURN_OK)
407 		return false;
408 
409 	*sec_caps = res.result.capabilities;
410 	return true;
411 }
412 
413 static struct tee_shm_pool *optee_config_dyn_shm(void)
414 {
415 	struct tee_shm_pool_mgr *priv_mgr;
416 	struct tee_shm_pool_mgr *dmabuf_mgr;
417 	void *rc;
418 
419 	rc = optee_shm_pool_alloc_pages();
420 	if (IS_ERR(rc))
421 		return rc;
422 	priv_mgr = rc;
423 
424 	rc = optee_shm_pool_alloc_pages();
425 	if (IS_ERR(rc)) {
426 		tee_shm_pool_mgr_destroy(priv_mgr);
427 		return rc;
428 	}
429 	dmabuf_mgr = rc;
430 
431 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
432 	if (IS_ERR(rc)) {
433 		tee_shm_pool_mgr_destroy(priv_mgr);
434 		tee_shm_pool_mgr_destroy(dmabuf_mgr);
435 	}
436 
437 	return rc;
438 }
439 
440 static struct tee_shm_pool *
441 optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
442 {
443 	union {
444 		struct arm_smccc_res smccc;
445 		struct optee_smc_get_shm_config_result result;
446 	} res;
447 	unsigned long vaddr;
448 	phys_addr_t paddr;
449 	size_t size;
450 	phys_addr_t begin;
451 	phys_addr_t end;
452 	void *va;
453 	struct tee_shm_pool_mgr *priv_mgr;
454 	struct tee_shm_pool_mgr *dmabuf_mgr;
455 	void *rc;
456 	const int sz = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
457 
458 	invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
459 	if (res.result.status != OPTEE_SMC_RETURN_OK) {
460 		pr_err("static shm service not available\n");
461 		return ERR_PTR(-ENOENT);
462 	}
463 
464 	if (res.result.settings != OPTEE_SMC_SHM_CACHED) {
465 		pr_err("only normal cached shared memory supported\n");
466 		return ERR_PTR(-EINVAL);
467 	}
468 
469 	begin = roundup(res.result.start, PAGE_SIZE);
470 	end = rounddown(res.result.start + res.result.size, PAGE_SIZE);
471 	paddr = begin;
472 	size = end - begin;
473 
474 	if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) {
475 		pr_err("too small shared memory area\n");
476 		return ERR_PTR(-EINVAL);
477 	}
478 
479 	va = memremap(paddr, size, MEMREMAP_WB);
480 	if (!va) {
481 		pr_err("shared memory ioremap failed\n");
482 		return ERR_PTR(-EINVAL);
483 	}
484 	vaddr = (unsigned long)va;
485 
486 	rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, sz,
487 					    3 /* 8 bytes aligned */);
488 	if (IS_ERR(rc))
489 		goto err_memunmap;
490 	priv_mgr = rc;
491 
492 	vaddr += sz;
493 	paddr += sz;
494 	size -= sz;
495 
496 	rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, size, PAGE_SHIFT);
497 	if (IS_ERR(rc))
498 		goto err_free_priv_mgr;
499 	dmabuf_mgr = rc;
500 
501 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
502 	if (IS_ERR(rc))
503 		goto err_free_dmabuf_mgr;
504 
505 	*memremaped_shm = va;
506 
507 	return rc;
508 
509 err_free_dmabuf_mgr:
510 	tee_shm_pool_mgr_destroy(dmabuf_mgr);
511 err_free_priv_mgr:
512 	tee_shm_pool_mgr_destroy(priv_mgr);
513 err_memunmap:
514 	memunmap(va);
515 	return rc;
516 }
517 
518 /* Simple wrapper functions to be able to use a function pointer */
519 static void optee_smccc_smc(unsigned long a0, unsigned long a1,
520 			    unsigned long a2, unsigned long a3,
521 			    unsigned long a4, unsigned long a5,
522 			    unsigned long a6, unsigned long a7,
523 			    struct arm_smccc_res *res)
524 {
525 	arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res);
526 }
527 
528 static void optee_smccc_hvc(unsigned long a0, unsigned long a1,
529 			    unsigned long a2, unsigned long a3,
530 			    unsigned long a4, unsigned long a5,
531 			    unsigned long a6, unsigned long a7,
532 			    struct arm_smccc_res *res)
533 {
534 	arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res);
535 }
536 
537 static optee_invoke_fn *get_invoke_func(struct device_node *np)
538 {
539 	const char *method;
540 
541 	pr_info("probing for conduit method from DT.\n");
542 
543 	if (of_property_read_string(np, "method", &method)) {
544 		pr_warn("missing \"method\" property\n");
545 		return ERR_PTR(-ENXIO);
546 	}
547 
548 	if (!strcmp("hvc", method))
549 		return optee_smccc_hvc;
550 	else if (!strcmp("smc", method))
551 		return optee_smccc_smc;
552 
553 	pr_warn("invalid \"method\" property: %s\n", method);
554 	return ERR_PTR(-EINVAL);
555 }
556 
557 static struct optee *optee_probe(struct device_node *np)
558 {
559 	optee_invoke_fn *invoke_fn;
560 	struct tee_shm_pool *pool = ERR_PTR(-EINVAL);
561 	struct optee *optee = NULL;
562 	void *memremaped_shm = NULL;
563 	struct tee_device *teedev;
564 	u32 sec_caps;
565 	int rc;
566 
567 	invoke_fn = get_invoke_func(np);
568 	if (IS_ERR(invoke_fn))
569 		return (void *)invoke_fn;
570 
571 	if (!optee_msg_api_uid_is_optee_api(invoke_fn)) {
572 		pr_warn("api uid mismatch\n");
573 		return ERR_PTR(-EINVAL);
574 	}
575 
576 	optee_msg_get_os_revision(invoke_fn);
577 
578 	if (!optee_msg_api_revision_is_compatible(invoke_fn)) {
579 		pr_warn("api revision mismatch\n");
580 		return ERR_PTR(-EINVAL);
581 	}
582 
583 	if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) {
584 		pr_warn("capabilities mismatch\n");
585 		return ERR_PTR(-EINVAL);
586 	}
587 
588 	/*
589 	 * Try to use dynamic shared memory if possible
590 	 */
591 	if (sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
592 		pool = optee_config_dyn_shm();
593 
594 	/*
595 	 * If dynamic shared memory is not available or failed - try static one
596 	 */
597 	if (IS_ERR(pool) && (sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM))
598 		pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm);
599 
600 	if (IS_ERR(pool))
601 		return (void *)pool;
602 
603 	optee = kzalloc(sizeof(*optee), GFP_KERNEL);
604 	if (!optee) {
605 		rc = -ENOMEM;
606 		goto err;
607 	}
608 
609 	optee->invoke_fn = invoke_fn;
610 	optee->sec_caps = sec_caps;
611 
612 	teedev = tee_device_alloc(&optee_desc, NULL, pool, optee);
613 	if (IS_ERR(teedev)) {
614 		rc = PTR_ERR(teedev);
615 		goto err;
616 	}
617 	optee->teedev = teedev;
618 
619 	teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee);
620 	if (IS_ERR(teedev)) {
621 		rc = PTR_ERR(teedev);
622 		goto err;
623 	}
624 	optee->supp_teedev = teedev;
625 
626 	rc = tee_device_register(optee->teedev);
627 	if (rc)
628 		goto err;
629 
630 	rc = tee_device_register(optee->supp_teedev);
631 	if (rc)
632 		goto err;
633 
634 	mutex_init(&optee->call_queue.mutex);
635 	INIT_LIST_HEAD(&optee->call_queue.waiters);
636 	optee_wait_queue_init(&optee->wait_queue);
637 	optee_supp_init(&optee->supp);
638 	optee->memremaped_shm = memremaped_shm;
639 	optee->pool = pool;
640 
641 	optee_enable_shm_cache(optee);
642 
643 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
644 		pr_info("dynamic shared memory is enabled\n");
645 
646 	return optee;
647 err:
648 	if (optee) {
649 		/*
650 		 * tee_device_unregister() is safe to call even if the
651 		 * devices hasn't been registered with
652 		 * tee_device_register() yet.
653 		 */
654 		tee_device_unregister(optee->supp_teedev);
655 		tee_device_unregister(optee->teedev);
656 		kfree(optee);
657 	}
658 	if (pool)
659 		tee_shm_pool_free(pool);
660 	if (memremaped_shm)
661 		memunmap(memremaped_shm);
662 	return ERR_PTR(rc);
663 }
664 
665 static void optee_remove(struct optee *optee)
666 {
667 	/*
668 	 * Ask OP-TEE to free all cached shared memory objects to decrease
669 	 * reference counters and also avoid wild pointers in secure world
670 	 * into the old shared memory range.
671 	 */
672 	optee_disable_shm_cache(optee);
673 
674 	/*
675 	 * The two devices has to be unregistered before we can free the
676 	 * other resources.
677 	 */
678 	tee_device_unregister(optee->supp_teedev);
679 	tee_device_unregister(optee->teedev);
680 
681 	tee_shm_pool_free(optee->pool);
682 	if (optee->memremaped_shm)
683 		memunmap(optee->memremaped_shm);
684 	optee_wait_queue_exit(&optee->wait_queue);
685 	optee_supp_uninit(&optee->supp);
686 	mutex_destroy(&optee->call_queue.mutex);
687 
688 	kfree(optee);
689 }
690 
691 static const struct of_device_id optee_match[] = {
692 	{ .compatible = "linaro,optee-tz" },
693 	{},
694 };
695 
696 static struct optee *optee_svc;
697 
698 static int __init optee_driver_init(void)
699 {
700 	struct device_node *fw_np = NULL;
701 	struct device_node *np = NULL;
702 	struct optee *optee = NULL;
703 	int rc = 0;
704 
705 	/* Node is supposed to be below /firmware */
706 	fw_np = of_find_node_by_name(NULL, "firmware");
707 	if (!fw_np)
708 		return -ENODEV;
709 
710 	np = of_find_matching_node(fw_np, optee_match);
711 	if (!np || !of_device_is_available(np)) {
712 		of_node_put(np);
713 		return -ENODEV;
714 	}
715 
716 	optee = optee_probe(np);
717 	of_node_put(np);
718 
719 	if (IS_ERR(optee))
720 		return PTR_ERR(optee);
721 
722 	rc = optee_enumerate_devices();
723 	if (rc) {
724 		optee_remove(optee);
725 		return rc;
726 	}
727 
728 	pr_info("initialized driver\n");
729 
730 	optee_svc = optee;
731 
732 	return 0;
733 }
734 module_init(optee_driver_init);
735 
736 static void __exit optee_driver_exit(void)
737 {
738 	struct optee *optee = optee_svc;
739 
740 	optee_svc = NULL;
741 	if (optee)
742 		optee_remove(optee);
743 }
744 module_exit(optee_driver_exit);
745 
746 MODULE_AUTHOR("Linaro");
747 MODULE_DESCRIPTION("OP-TEE driver");
748 MODULE_SUPPORTED_DEVICE("");
749 MODULE_VERSION("1.0");
750 MODULE_LICENSE("GPL v2");
751