xref: /openbmc/linux/drivers/tee/optee/core.c (revision 0eb76ba2)
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 <linux/workqueue.h>
21 #include "optee_private.h"
22 #include "optee_smc.h"
23 #include "shm_pool.h"
24 
25 #define DRIVER_NAME "optee"
26 
27 #define OPTEE_SHM_NUM_PRIV_PAGES	CONFIG_OPTEE_SHM_NUM_PRIV_PAGES
28 
29 /**
30  * optee_from_msg_param() - convert from OPTEE_MSG parameters to
31  *			    struct tee_param
32  * @params:	subsystem internal parameter representation
33  * @num_params:	number of elements in the parameter arrays
34  * @msg_params:	OPTEE_MSG parameters
35  * Returns 0 on success or <0 on failure
36  */
37 int optee_from_msg_param(struct tee_param *params, size_t num_params,
38 			 const struct optee_msg_param *msg_params)
39 {
40 	int rc;
41 	size_t n;
42 	struct tee_shm *shm;
43 	phys_addr_t pa;
44 
45 	for (n = 0; n < num_params; n++) {
46 		struct tee_param *p = params + n;
47 		const struct optee_msg_param *mp = msg_params + n;
48 		u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK;
49 
50 		switch (attr) {
51 		case OPTEE_MSG_ATTR_TYPE_NONE:
52 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
53 			memset(&p->u, 0, sizeof(p->u));
54 			break;
55 		case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT:
56 		case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT:
57 		case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT:
58 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT +
59 				  attr - OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
60 			p->u.value.a = mp->u.value.a;
61 			p->u.value.b = mp->u.value.b;
62 			p->u.value.c = mp->u.value.c;
63 			break;
64 		case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT:
65 		case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT:
66 		case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT:
67 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
68 				  attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT;
69 			p->u.memref.size = mp->u.tmem.size;
70 			shm = (struct tee_shm *)(unsigned long)
71 				mp->u.tmem.shm_ref;
72 			if (!shm) {
73 				p->u.memref.shm_offs = 0;
74 				p->u.memref.shm = NULL;
75 				break;
76 			}
77 			rc = tee_shm_get_pa(shm, 0, &pa);
78 			if (rc)
79 				return rc;
80 			p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa;
81 			p->u.memref.shm = shm;
82 
83 			/* Check that the memref is covered by the shm object */
84 			if (p->u.memref.size) {
85 				size_t o = p->u.memref.shm_offs +
86 					   p->u.memref.size - 1;
87 
88 				rc = tee_shm_get_pa(shm, o, NULL);
89 				if (rc)
90 					return rc;
91 			}
92 			break;
93 		case OPTEE_MSG_ATTR_TYPE_RMEM_INPUT:
94 		case OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT:
95 		case OPTEE_MSG_ATTR_TYPE_RMEM_INOUT:
96 			p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
97 				  attr - OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
98 			p->u.memref.size = mp->u.rmem.size;
99 			shm = (struct tee_shm *)(unsigned long)
100 				mp->u.rmem.shm_ref;
101 
102 			if (!shm) {
103 				p->u.memref.shm_offs = 0;
104 				p->u.memref.shm = NULL;
105 				break;
106 			}
107 			p->u.memref.shm_offs = mp->u.rmem.offs;
108 			p->u.memref.shm = shm;
109 
110 			break;
111 
112 		default:
113 			return -EINVAL;
114 		}
115 	}
116 	return 0;
117 }
118 
119 static int to_msg_param_tmp_mem(struct optee_msg_param *mp,
120 				const struct tee_param *p)
121 {
122 	int rc;
123 	phys_addr_t pa;
124 
125 	mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT + p->attr -
126 		   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
127 
128 	mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm;
129 	mp->u.tmem.size = p->u.memref.size;
130 
131 	if (!p->u.memref.shm) {
132 		mp->u.tmem.buf_ptr = 0;
133 		return 0;
134 	}
135 
136 	rc = tee_shm_get_pa(p->u.memref.shm, p->u.memref.shm_offs, &pa);
137 	if (rc)
138 		return rc;
139 
140 	mp->u.tmem.buf_ptr = pa;
141 	mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED <<
142 		    OPTEE_MSG_ATTR_CACHE_SHIFT;
143 
144 	return 0;
145 }
146 
147 static int to_msg_param_reg_mem(struct optee_msg_param *mp,
148 				const struct tee_param *p)
149 {
150 	mp->attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT + p->attr -
151 		   TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
152 
153 	mp->u.rmem.shm_ref = (unsigned long)p->u.memref.shm;
154 	mp->u.rmem.size = p->u.memref.size;
155 	mp->u.rmem.offs = p->u.memref.shm_offs;
156 	return 0;
157 }
158 
159 /**
160  * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters
161  * @msg_params:	OPTEE_MSG parameters
162  * @num_params:	number of elements in the parameter arrays
163  * @params:	subsystem itnernal parameter representation
164  * Returns 0 on success or <0 on failure
165  */
166 int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params,
167 		       const struct tee_param *params)
168 {
169 	int rc;
170 	size_t n;
171 
172 	for (n = 0; n < num_params; n++) {
173 		const struct tee_param *p = params + n;
174 		struct optee_msg_param *mp = msg_params + n;
175 
176 		switch (p->attr) {
177 		case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
178 			mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
179 			memset(&mp->u, 0, sizeof(mp->u));
180 			break;
181 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
182 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
183 		case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
184 			mp->attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT + p->attr -
185 				   TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
186 			mp->u.value.a = p->u.value.a;
187 			mp->u.value.b = p->u.value.b;
188 			mp->u.value.c = p->u.value.c;
189 			break;
190 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
191 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
192 		case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
193 			if (tee_shm_is_registered(p->u.memref.shm))
194 				rc = to_msg_param_reg_mem(mp, p);
195 			else
196 				rc = to_msg_param_tmp_mem(mp, p);
197 			if (rc)
198 				return rc;
199 			break;
200 		default:
201 			return -EINVAL;
202 		}
203 	}
204 	return 0;
205 }
206 
207 static void optee_get_version(struct tee_device *teedev,
208 			      struct tee_ioctl_version_data *vers)
209 {
210 	struct tee_ioctl_version_data v = {
211 		.impl_id = TEE_IMPL_ID_OPTEE,
212 		.impl_caps = TEE_OPTEE_CAP_TZ,
213 		.gen_caps = TEE_GEN_CAP_GP,
214 	};
215 	struct optee *optee = tee_get_drvdata(teedev);
216 
217 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
218 		v.gen_caps |= TEE_GEN_CAP_REG_MEM;
219 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_MEMREF_NULL)
220 		v.gen_caps |= TEE_GEN_CAP_MEMREF_NULL;
221 	*vers = v;
222 }
223 
224 static void optee_bus_scan(struct work_struct *work)
225 {
226 	WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
227 }
228 
229 static int optee_open(struct tee_context *ctx)
230 {
231 	struct optee_context_data *ctxdata;
232 	struct tee_device *teedev = ctx->teedev;
233 	struct optee *optee = tee_get_drvdata(teedev);
234 
235 	ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
236 	if (!ctxdata)
237 		return -ENOMEM;
238 
239 	if (teedev == optee->supp_teedev) {
240 		bool busy = true;
241 
242 		mutex_lock(&optee->supp.mutex);
243 		if (!optee->supp.ctx) {
244 			busy = false;
245 			optee->supp.ctx = ctx;
246 		}
247 		mutex_unlock(&optee->supp.mutex);
248 		if (busy) {
249 			kfree(ctxdata);
250 			return -EBUSY;
251 		}
252 
253 		if (!optee->scan_bus_done) {
254 			INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
255 			optee->scan_bus_wq = create_workqueue("optee_bus_scan");
256 			if (!optee->scan_bus_wq) {
257 				kfree(ctxdata);
258 				return -ECHILD;
259 			}
260 			queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
261 			optee->scan_bus_done = true;
262 		}
263 	}
264 	mutex_init(&ctxdata->mutex);
265 	INIT_LIST_HEAD(&ctxdata->sess_list);
266 
267 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_MEMREF_NULL)
268 		ctx->cap_memref_null  = true;
269 	else
270 		ctx->cap_memref_null = false;
271 
272 	ctx->data = ctxdata;
273 	return 0;
274 }
275 
276 static void optee_release(struct tee_context *ctx)
277 {
278 	struct optee_context_data *ctxdata = ctx->data;
279 	struct tee_device *teedev = ctx->teedev;
280 	struct optee *optee = tee_get_drvdata(teedev);
281 	struct tee_shm *shm;
282 	struct optee_msg_arg *arg = NULL;
283 	phys_addr_t parg;
284 	struct optee_session *sess;
285 	struct optee_session *sess_tmp;
286 
287 	if (!ctxdata)
288 		return;
289 
290 	shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED);
291 	if (!IS_ERR(shm)) {
292 		arg = tee_shm_get_va(shm, 0);
293 		/*
294 		 * If va2pa fails for some reason, we can't call into
295 		 * secure world, only free the memory. Secure OS will leak
296 		 * sessions and finally refuse more sessions, but we will
297 		 * at least let normal world reclaim its memory.
298 		 */
299 		if (!IS_ERR(arg))
300 			if (tee_shm_va2pa(shm, arg, &parg))
301 				arg = NULL; /* prevent usage of parg below */
302 	}
303 
304 	list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
305 				 list_node) {
306 		list_del(&sess->list_node);
307 		if (!IS_ERR_OR_NULL(arg)) {
308 			memset(arg, 0, sizeof(*arg));
309 			arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
310 			arg->session = sess->session_id;
311 			optee_do_call_with_arg(ctx, parg);
312 		}
313 		kfree(sess);
314 	}
315 	kfree(ctxdata);
316 
317 	if (!IS_ERR(shm))
318 		tee_shm_free(shm);
319 
320 	ctx->data = NULL;
321 
322 	if (teedev == optee->supp_teedev) {
323 		if (optee->scan_bus_wq) {
324 			destroy_workqueue(optee->scan_bus_wq);
325 			optee->scan_bus_wq = NULL;
326 		}
327 		optee_supp_release(&optee->supp);
328 	}
329 }
330 
331 static const struct tee_driver_ops optee_ops = {
332 	.get_version = optee_get_version,
333 	.open = optee_open,
334 	.release = optee_release,
335 	.open_session = optee_open_session,
336 	.close_session = optee_close_session,
337 	.invoke_func = optee_invoke_func,
338 	.cancel_req = optee_cancel_req,
339 	.shm_register = optee_shm_register,
340 	.shm_unregister = optee_shm_unregister,
341 };
342 
343 static const struct tee_desc optee_desc = {
344 	.name = DRIVER_NAME "-clnt",
345 	.ops = &optee_ops,
346 	.owner = THIS_MODULE,
347 };
348 
349 static const struct tee_driver_ops optee_supp_ops = {
350 	.get_version = optee_get_version,
351 	.open = optee_open,
352 	.release = optee_release,
353 	.supp_recv = optee_supp_recv,
354 	.supp_send = optee_supp_send,
355 	.shm_register = optee_shm_register_supp,
356 	.shm_unregister = optee_shm_unregister_supp,
357 };
358 
359 static const struct tee_desc optee_supp_desc = {
360 	.name = DRIVER_NAME "-supp",
361 	.ops = &optee_supp_ops,
362 	.owner = THIS_MODULE,
363 	.flags = TEE_DESC_PRIVILEGED,
364 };
365 
366 static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
367 {
368 	struct arm_smccc_res res;
369 
370 	invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res);
371 
372 	if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 &&
373 	    res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3)
374 		return true;
375 	return false;
376 }
377 
378 static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn)
379 {
380 	union {
381 		struct arm_smccc_res smccc;
382 		struct optee_smc_call_get_os_revision_result result;
383 	} res = {
384 		.result = {
385 			.build_id = 0
386 		}
387 	};
388 
389 	invoke_fn(OPTEE_SMC_CALL_GET_OS_REVISION, 0, 0, 0, 0, 0, 0, 0,
390 		  &res.smccc);
391 
392 	if (res.result.build_id)
393 		pr_info("revision %lu.%lu (%08lx)", res.result.major,
394 			res.result.minor, res.result.build_id);
395 	else
396 		pr_info("revision %lu.%lu", res.result.major, res.result.minor);
397 }
398 
399 static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
400 {
401 	union {
402 		struct arm_smccc_res smccc;
403 		struct optee_smc_calls_revision_result result;
404 	} res;
405 
406 	invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
407 
408 	if (res.result.major == OPTEE_MSG_REVISION_MAJOR &&
409 	    (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR)
410 		return true;
411 	return false;
412 }
413 
414 static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
415 					    u32 *sec_caps)
416 {
417 	union {
418 		struct arm_smccc_res smccc;
419 		struct optee_smc_exchange_capabilities_result result;
420 	} res;
421 	u32 a1 = 0;
422 
423 	/*
424 	 * TODO This isn't enough to tell if it's UP system (from kernel
425 	 * point of view) or not, is_smp() returns the the information
426 	 * needed, but can't be called directly from here.
427 	 */
428 	if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1)
429 		a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR;
430 
431 	invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0,
432 		  &res.smccc);
433 
434 	if (res.result.status != OPTEE_SMC_RETURN_OK)
435 		return false;
436 
437 	*sec_caps = res.result.capabilities;
438 	return true;
439 }
440 
441 static struct tee_shm_pool *optee_config_dyn_shm(void)
442 {
443 	struct tee_shm_pool_mgr *priv_mgr;
444 	struct tee_shm_pool_mgr *dmabuf_mgr;
445 	void *rc;
446 
447 	rc = optee_shm_pool_alloc_pages();
448 	if (IS_ERR(rc))
449 		return rc;
450 	priv_mgr = rc;
451 
452 	rc = optee_shm_pool_alloc_pages();
453 	if (IS_ERR(rc)) {
454 		tee_shm_pool_mgr_destroy(priv_mgr);
455 		return rc;
456 	}
457 	dmabuf_mgr = rc;
458 
459 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
460 	if (IS_ERR(rc)) {
461 		tee_shm_pool_mgr_destroy(priv_mgr);
462 		tee_shm_pool_mgr_destroy(dmabuf_mgr);
463 	}
464 
465 	return rc;
466 }
467 
468 static struct tee_shm_pool *
469 optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm)
470 {
471 	union {
472 		struct arm_smccc_res smccc;
473 		struct optee_smc_get_shm_config_result result;
474 	} res;
475 	unsigned long vaddr;
476 	phys_addr_t paddr;
477 	size_t size;
478 	phys_addr_t begin;
479 	phys_addr_t end;
480 	void *va;
481 	struct tee_shm_pool_mgr *priv_mgr;
482 	struct tee_shm_pool_mgr *dmabuf_mgr;
483 	void *rc;
484 	const int sz = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
485 
486 	invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
487 	if (res.result.status != OPTEE_SMC_RETURN_OK) {
488 		pr_err("static shm service not available\n");
489 		return ERR_PTR(-ENOENT);
490 	}
491 
492 	if (res.result.settings != OPTEE_SMC_SHM_CACHED) {
493 		pr_err("only normal cached shared memory supported\n");
494 		return ERR_PTR(-EINVAL);
495 	}
496 
497 	begin = roundup(res.result.start, PAGE_SIZE);
498 	end = rounddown(res.result.start + res.result.size, PAGE_SIZE);
499 	paddr = begin;
500 	size = end - begin;
501 
502 	if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) {
503 		pr_err("too small shared memory area\n");
504 		return ERR_PTR(-EINVAL);
505 	}
506 
507 	va = memremap(paddr, size, MEMREMAP_WB);
508 	if (!va) {
509 		pr_err("shared memory ioremap failed\n");
510 		return ERR_PTR(-EINVAL);
511 	}
512 	vaddr = (unsigned long)va;
513 
514 	rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, sz,
515 					    3 /* 8 bytes aligned */);
516 	if (IS_ERR(rc))
517 		goto err_memunmap;
518 	priv_mgr = rc;
519 
520 	vaddr += sz;
521 	paddr += sz;
522 	size -= sz;
523 
524 	rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, size, PAGE_SHIFT);
525 	if (IS_ERR(rc))
526 		goto err_free_priv_mgr;
527 	dmabuf_mgr = rc;
528 
529 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
530 	if (IS_ERR(rc))
531 		goto err_free_dmabuf_mgr;
532 
533 	*memremaped_shm = va;
534 
535 	return rc;
536 
537 err_free_dmabuf_mgr:
538 	tee_shm_pool_mgr_destroy(dmabuf_mgr);
539 err_free_priv_mgr:
540 	tee_shm_pool_mgr_destroy(priv_mgr);
541 err_memunmap:
542 	memunmap(va);
543 	return rc;
544 }
545 
546 /* Simple wrapper functions to be able to use a function pointer */
547 static void optee_smccc_smc(unsigned long a0, unsigned long a1,
548 			    unsigned long a2, unsigned long a3,
549 			    unsigned long a4, unsigned long a5,
550 			    unsigned long a6, unsigned long a7,
551 			    struct arm_smccc_res *res)
552 {
553 	arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res);
554 }
555 
556 static void optee_smccc_hvc(unsigned long a0, unsigned long a1,
557 			    unsigned long a2, unsigned long a3,
558 			    unsigned long a4, unsigned long a5,
559 			    unsigned long a6, unsigned long a7,
560 			    struct arm_smccc_res *res)
561 {
562 	arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res);
563 }
564 
565 static optee_invoke_fn *get_invoke_func(struct device *dev)
566 {
567 	const char *method;
568 
569 	pr_info("probing for conduit method.\n");
570 
571 	if (device_property_read_string(dev, "method", &method)) {
572 		pr_warn("missing \"method\" property\n");
573 		return ERR_PTR(-ENXIO);
574 	}
575 
576 	if (!strcmp("hvc", method))
577 		return optee_smccc_hvc;
578 	else if (!strcmp("smc", method))
579 		return optee_smccc_smc;
580 
581 	pr_warn("invalid \"method\" property: %s\n", method);
582 	return ERR_PTR(-EINVAL);
583 }
584 
585 static int optee_remove(struct platform_device *pdev)
586 {
587 	struct optee *optee = platform_get_drvdata(pdev);
588 
589 	/*
590 	 * Ask OP-TEE to free all cached shared memory objects to decrease
591 	 * reference counters and also avoid wild pointers in secure world
592 	 * into the old shared memory range.
593 	 */
594 	optee_disable_shm_cache(optee);
595 
596 	/*
597 	 * The two devices have to be unregistered before we can free the
598 	 * other resources.
599 	 */
600 	tee_device_unregister(optee->supp_teedev);
601 	tee_device_unregister(optee->teedev);
602 
603 	tee_shm_pool_free(optee->pool);
604 	if (optee->memremaped_shm)
605 		memunmap(optee->memremaped_shm);
606 	optee_wait_queue_exit(&optee->wait_queue);
607 	optee_supp_uninit(&optee->supp);
608 	mutex_destroy(&optee->call_queue.mutex);
609 
610 	kfree(optee);
611 
612 	return 0;
613 }
614 
615 static int optee_probe(struct platform_device *pdev)
616 {
617 	optee_invoke_fn *invoke_fn;
618 	struct tee_shm_pool *pool = ERR_PTR(-EINVAL);
619 	struct optee *optee = NULL;
620 	void *memremaped_shm = NULL;
621 	struct tee_device *teedev;
622 	u32 sec_caps;
623 	int rc;
624 
625 	invoke_fn = get_invoke_func(&pdev->dev);
626 	if (IS_ERR(invoke_fn))
627 		return PTR_ERR(invoke_fn);
628 
629 	if (!optee_msg_api_uid_is_optee_api(invoke_fn)) {
630 		pr_warn("api uid mismatch\n");
631 		return -EINVAL;
632 	}
633 
634 	optee_msg_get_os_revision(invoke_fn);
635 
636 	if (!optee_msg_api_revision_is_compatible(invoke_fn)) {
637 		pr_warn("api revision mismatch\n");
638 		return -EINVAL;
639 	}
640 
641 	if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) {
642 		pr_warn("capabilities mismatch\n");
643 		return -EINVAL;
644 	}
645 
646 	/*
647 	 * Try to use dynamic shared memory if possible
648 	 */
649 	if (sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
650 		pool = optee_config_dyn_shm();
651 
652 	/*
653 	 * If dynamic shared memory is not available or failed - try static one
654 	 */
655 	if (IS_ERR(pool) && (sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM))
656 		pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm);
657 
658 	if (IS_ERR(pool))
659 		return PTR_ERR(pool);
660 
661 	optee = kzalloc(sizeof(*optee), GFP_KERNEL);
662 	if (!optee) {
663 		rc = -ENOMEM;
664 		goto err;
665 	}
666 
667 	optee->invoke_fn = invoke_fn;
668 	optee->sec_caps = sec_caps;
669 
670 	teedev = tee_device_alloc(&optee_desc, NULL, pool, optee);
671 	if (IS_ERR(teedev)) {
672 		rc = PTR_ERR(teedev);
673 		goto err;
674 	}
675 	optee->teedev = teedev;
676 
677 	teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee);
678 	if (IS_ERR(teedev)) {
679 		rc = PTR_ERR(teedev);
680 		goto err;
681 	}
682 	optee->supp_teedev = teedev;
683 
684 	rc = tee_device_register(optee->teedev);
685 	if (rc)
686 		goto err;
687 
688 	rc = tee_device_register(optee->supp_teedev);
689 	if (rc)
690 		goto err;
691 
692 	mutex_init(&optee->call_queue.mutex);
693 	INIT_LIST_HEAD(&optee->call_queue.waiters);
694 	optee_wait_queue_init(&optee->wait_queue);
695 	optee_supp_init(&optee->supp);
696 	optee->memremaped_shm = memremaped_shm;
697 	optee->pool = pool;
698 
699 	optee_enable_shm_cache(optee);
700 
701 	if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
702 		pr_info("dynamic shared memory is enabled\n");
703 
704 	platform_set_drvdata(pdev, optee);
705 
706 	rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
707 	if (rc) {
708 		optee_remove(pdev);
709 		return rc;
710 	}
711 
712 	pr_info("initialized driver\n");
713 	return 0;
714 err:
715 	if (optee) {
716 		/*
717 		 * tee_device_unregister() is safe to call even if the
718 		 * devices hasn't been registered with
719 		 * tee_device_register() yet.
720 		 */
721 		tee_device_unregister(optee->supp_teedev);
722 		tee_device_unregister(optee->teedev);
723 		kfree(optee);
724 	}
725 	if (pool)
726 		tee_shm_pool_free(pool);
727 	if (memremaped_shm)
728 		memunmap(memremaped_shm);
729 	return rc;
730 }
731 
732 static const struct of_device_id optee_dt_match[] = {
733 	{ .compatible = "linaro,optee-tz" },
734 	{},
735 };
736 MODULE_DEVICE_TABLE(of, optee_dt_match);
737 
738 static struct platform_driver optee_driver = {
739 	.probe  = optee_probe,
740 	.remove = optee_remove,
741 	.driver = {
742 		.name = "optee",
743 		.of_match_table = optee_dt_match,
744 	},
745 };
746 module_platform_driver(optee_driver);
747 
748 MODULE_AUTHOR("Linaro");
749 MODULE_DESCRIPTION("OP-TEE driver");
750 MODULE_SUPPORTED_DEVICE("");
751 MODULE_VERSION("1.0");
752 MODULE_LICENSE("GPL v2");
753 MODULE_ALIAS("platform:optee");
754