0842b6e6af822c5a3230c95084169e1346517ff9
[sfrench/cifs-2.6.git] / drivers / tee / optee / core.c
1 /*
2  * Copyright (c) 2015, Linaro Limited
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  */
14
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17 #include <linux/arm-smccc.h>
18 #include <linux/errno.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_platform.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/string.h>
26 #include <linux/tee_drv.h>
27 #include <linux/types.h>
28 #include <linux/uaccess.h>
29 #include "optee_private.h"
30 #include "optee_smc.h"
31 #include "shm_pool.h"
32
33 #define DRIVER_NAME "optee"
34
35 #define OPTEE_SHM_NUM_PRIV_PAGES        CONFIG_OPTEE_SHM_NUM_PRIV_PAGES
36
37 /**
38  * optee_from_msg_param() - convert from OPTEE_MSG parameters to
39  *                          struct tee_param
40  * @params:     subsystem internal parameter representation
41  * @num_params: number of elements in the parameter arrays
42  * @msg_params: OPTEE_MSG parameters
43  * Returns 0 on success or <0 on failure
44  */
45 int optee_from_msg_param(struct tee_param *params, size_t num_params,
46                          const struct optee_msg_param *msg_params)
47 {
48         int rc;
49         size_t n;
50         struct tee_shm *shm;
51         phys_addr_t pa;
52
53         for (n = 0; n < num_params; n++) {
54                 struct tee_param *p = params + n;
55                 const struct optee_msg_param *mp = msg_params + n;
56                 u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK;
57
58                 switch (attr) {
59                 case OPTEE_MSG_ATTR_TYPE_NONE:
60                         p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
61                         memset(&p->u, 0, sizeof(p->u));
62                         break;
63                 case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT:
64                 case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT:
65                 case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT:
66                         p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT +
67                                   attr - OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
68                         p->u.value.a = mp->u.value.a;
69                         p->u.value.b = mp->u.value.b;
70                         p->u.value.c = mp->u.value.c;
71                         break;
72                 case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT:
73                 case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT:
74                 case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT:
75                         p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
76                                   attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT;
77                         p->u.memref.size = mp->u.tmem.size;
78                         shm = (struct tee_shm *)(unsigned long)
79                                 mp->u.tmem.shm_ref;
80                         if (!shm) {
81                                 p->u.memref.shm_offs = 0;
82                                 p->u.memref.shm = NULL;
83                                 break;
84                         }
85                         rc = tee_shm_get_pa(shm, 0, &pa);
86                         if (rc)
87                                 return rc;
88                         p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa;
89                         p->u.memref.shm = shm;
90
91                         /* Check that the memref is covered by the shm object */
92                         if (p->u.memref.size) {
93                                 size_t o = p->u.memref.shm_offs +
94                                            p->u.memref.size - 1;
95
96                                 rc = tee_shm_get_pa(shm, o, NULL);
97                                 if (rc)
98                                         return rc;
99                         }
100                         break;
101                 case OPTEE_MSG_ATTR_TYPE_RMEM_INPUT:
102                 case OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT:
103                 case OPTEE_MSG_ATTR_TYPE_RMEM_INOUT:
104                         p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT +
105                                   attr - OPTEE_MSG_ATTR_TYPE_RMEM_INPUT;
106                         p->u.memref.size = mp->u.rmem.size;
107                         shm = (struct tee_shm *)(unsigned long)
108                                 mp->u.rmem.shm_ref;
109
110                         if (!shm) {
111                                 p->u.memref.shm_offs = 0;
112                                 p->u.memref.shm = NULL;
113                                 break;
114                         }
115                         p->u.memref.shm_offs = mp->u.rmem.offs;
116                         p->u.memref.shm = shm;
117
118                         break;
119
120                 default:
121                         return -EINVAL;
122                 }
123         }
124         return 0;
125 }
126
127 static int to_msg_param_tmp_mem(struct optee_msg_param *mp,
128                                 const struct tee_param *p)
129 {
130         int rc;
131         phys_addr_t pa;
132
133         mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT + p->attr -
134                    TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
135
136         mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm;
137         mp->u.tmem.size = p->u.memref.size;
138
139         if (!p->u.memref.shm) {
140                 mp->u.tmem.buf_ptr = 0;
141                 return 0;
142         }
143
144         rc = tee_shm_get_pa(p->u.memref.shm, p->u.memref.shm_offs, &pa);
145         if (rc)
146                 return rc;
147
148         mp->u.tmem.buf_ptr = pa;
149         mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED <<
150                     OPTEE_MSG_ATTR_CACHE_SHIFT;
151
152         return 0;
153 }
154
155 static int to_msg_param_reg_mem(struct optee_msg_param *mp,
156                                 const struct tee_param *p)
157 {
158         mp->attr = OPTEE_MSG_ATTR_TYPE_RMEM_INPUT + p->attr -
159                    TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
160
161         mp->u.rmem.shm_ref = (unsigned long)p->u.memref.shm;
162         mp->u.rmem.size = p->u.memref.size;
163         mp->u.rmem.offs = p->u.memref.shm_offs;
164         return 0;
165 }
166
167 /**
168  * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters
169  * @msg_params: OPTEE_MSG parameters
170  * @num_params: number of elements in the parameter arrays
171  * @params:     subsystem itnernal parameter representation
172  * Returns 0 on success or <0 on failure
173  */
174 int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params,
175                        const struct tee_param *params)
176 {
177         int rc;
178         size_t n;
179
180         for (n = 0; n < num_params; n++) {
181                 const struct tee_param *p = params + n;
182                 struct optee_msg_param *mp = msg_params + n;
183
184                 switch (p->attr) {
185                 case TEE_IOCTL_PARAM_ATTR_TYPE_NONE:
186                         mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE;
187                         memset(&mp->u, 0, sizeof(mp->u));
188                         break;
189                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT:
190                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT:
191                 case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT:
192                         mp->attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT + p->attr -
193                                    TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
194                         mp->u.value.a = p->u.value.a;
195                         mp->u.value.b = p->u.value.b;
196                         mp->u.value.c = p->u.value.c;
197                         break;
198                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT:
199                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT:
200                 case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT:
201                         if (tee_shm_is_registered(p->u.memref.shm))
202                                 rc = to_msg_param_reg_mem(mp, p);
203                         else
204                                 rc = to_msg_param_tmp_mem(mp, p);
205                         if (rc)
206                                 return rc;
207                         break;
208                 default:
209                         return -EINVAL;
210                 }
211         }
212         return 0;
213 }
214
215 static void optee_get_version(struct tee_device *teedev,
216                               struct tee_ioctl_version_data *vers)
217 {
218         struct tee_ioctl_version_data v = {
219                 .impl_id = TEE_IMPL_ID_OPTEE,
220                 .impl_caps = TEE_OPTEE_CAP_TZ,
221                 .gen_caps = TEE_GEN_CAP_GP,
222         };
223         struct optee *optee = tee_get_drvdata(teedev);
224
225         if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
226                 v.gen_caps |= TEE_GEN_CAP_REG_MEM;
227         *vers = v;
228 }
229
230 static int optee_open(struct tee_context *ctx)
231 {
232         struct optee_context_data *ctxdata;
233         struct tee_device *teedev = ctx->teedev;
234         struct optee *optee = tee_get_drvdata(teedev);
235
236         ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL);
237         if (!ctxdata)
238                 return -ENOMEM;
239
240         if (teedev == optee->supp_teedev) {
241                 bool busy = true;
242
243                 mutex_lock(&optee->supp.mutex);
244                 if (!optee->supp.ctx) {
245                         busy = false;
246                         optee->supp.ctx = ctx;
247                 }
248                 mutex_unlock(&optee->supp.mutex);
249                 if (busy) {
250                         kfree(ctxdata);
251                         return -EBUSY;
252                 }
253         }
254
255         mutex_init(&ctxdata->mutex);
256         INIT_LIST_HEAD(&ctxdata->sess_list);
257
258         ctx->data = ctxdata;
259         return 0;
260 }
261
262 static void optee_release(struct tee_context *ctx)
263 {
264         struct optee_context_data *ctxdata = ctx->data;
265         struct tee_device *teedev = ctx->teedev;
266         struct optee *optee = tee_get_drvdata(teedev);
267         struct tee_shm *shm;
268         struct optee_msg_arg *arg = NULL;
269         phys_addr_t parg;
270         struct optee_session *sess;
271         struct optee_session *sess_tmp;
272
273         if (!ctxdata)
274                 return;
275
276         shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED);
277         if (!IS_ERR(shm)) {
278                 arg = tee_shm_get_va(shm, 0);
279                 /*
280                  * If va2pa fails for some reason, we can't call into
281                  * secure world, only free the memory. Secure OS will leak
282                  * sessions and finally refuse more sessions, but we will
283                  * at least let normal world reclaim its memory.
284                  */
285                 if (!IS_ERR(arg))
286                         if (tee_shm_va2pa(shm, arg, &parg))
287                                 arg = NULL; /* prevent usage of parg below */
288         }
289
290         list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list,
291                                  list_node) {
292                 list_del(&sess->list_node);
293                 if (!IS_ERR_OR_NULL(arg)) {
294                         memset(arg, 0, sizeof(*arg));
295                         arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION;
296                         arg->session = sess->session_id;
297                         optee_do_call_with_arg(ctx, parg);
298                 }
299                 kfree(sess);
300         }
301         kfree(ctxdata);
302
303         if (!IS_ERR(shm))
304                 tee_shm_free(shm);
305
306         ctx->data = NULL;
307
308         if (teedev == optee->supp_teedev)
309                 optee_supp_release(&optee->supp);
310 }
311
312 static const struct tee_driver_ops optee_ops = {
313         .get_version = optee_get_version,
314         .open = optee_open,
315         .release = optee_release,
316         .open_session = optee_open_session,
317         .close_session = optee_close_session,
318         .invoke_func = optee_invoke_func,
319         .cancel_req = optee_cancel_req,
320         .shm_register = optee_shm_register,
321         .shm_unregister = optee_shm_unregister,
322 };
323
324 static const struct tee_desc optee_desc = {
325         .name = DRIVER_NAME "-clnt",
326         .ops = &optee_ops,
327         .owner = THIS_MODULE,
328 };
329
330 static const struct tee_driver_ops optee_supp_ops = {
331         .get_version = optee_get_version,
332         .open = optee_open,
333         .release = optee_release,
334         .supp_recv = optee_supp_recv,
335         .supp_send = optee_supp_send,
336         .shm_register = optee_shm_register_supp,
337         .shm_unregister = optee_shm_unregister_supp,
338 };
339
340 static const struct tee_desc optee_supp_desc = {
341         .name = DRIVER_NAME "-supp",
342         .ops = &optee_supp_ops,
343         .owner = THIS_MODULE,
344         .flags = TEE_DESC_PRIVILEGED,
345 };
346
347 static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
348 {
349         struct arm_smccc_res res;
350
351         invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res);
352
353         if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 &&
354             res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3)
355                 return true;
356         return false;
357 }
358
359 static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn)
360 {
361         union {
362                 struct arm_smccc_res smccc;
363                 struct optee_smc_call_get_os_revision_result result;
364         } res = {
365                 .result = {
366                         .build_id = 0
367                 }
368         };
369
370         invoke_fn(OPTEE_SMC_CALL_GET_OS_REVISION, 0, 0, 0, 0, 0, 0, 0,
371                   &res.smccc);
372
373         if (res.result.build_id)
374                 pr_info("revision %lu.%lu (%08lx)", res.result.major,
375                         res.result.minor, res.result.build_id);
376         else
377                 pr_info("revision %lu.%lu", res.result.major, res.result.minor);
378 }
379
380 static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
381 {
382         union {
383                 struct arm_smccc_res smccc;
384                 struct optee_smc_calls_revision_result result;
385         } res;
386
387         invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
388
389         if (res.result.major == OPTEE_MSG_REVISION_MAJOR &&
390             (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR)
391                 return true;
392         return false;
393 }
394
395 static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn,
396                                             u32 *sec_caps)
397 {
398         union {
399                 struct arm_smccc_res smccc;
400                 struct optee_smc_exchange_capabilities_result result;
401         } res;
402         u32 a1 = 0;
403
404         /*
405          * TODO This isn't enough to tell if it's UP system (from kernel
406          * point of view) or not, is_smp() returns the the information
407          * needed, but can't be called directly from here.
408          */
409         if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1)
410                 a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR;
411
412         invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0,
413                   &res.smccc);
414
415         if (res.result.status != OPTEE_SMC_RETURN_OK)
416                 return false;
417
418         *sec_caps = res.result.capabilities;
419         return true;
420 }
421
422 static struct tee_shm_pool *
423 optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm,
424                           u32 sec_caps)
425 {
426         union {
427                 struct arm_smccc_res smccc;
428                 struct optee_smc_get_shm_config_result result;
429         } res;
430         unsigned long vaddr;
431         phys_addr_t paddr;
432         size_t size;
433         phys_addr_t begin;
434         phys_addr_t end;
435         void *va;
436         struct tee_shm_pool_mgr *priv_mgr;
437         struct tee_shm_pool_mgr *dmabuf_mgr;
438         void *rc;
439
440         invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
441         if (res.result.status != OPTEE_SMC_RETURN_OK) {
442                 pr_info("shm service not available\n");
443                 return ERR_PTR(-ENOENT);
444         }
445
446         if (res.result.settings != OPTEE_SMC_SHM_CACHED) {
447                 pr_err("only normal cached shared memory supported\n");
448                 return ERR_PTR(-EINVAL);
449         }
450
451         begin = roundup(res.result.start, PAGE_SIZE);
452         end = rounddown(res.result.start + res.result.size, PAGE_SIZE);
453         paddr = begin;
454         size = end - begin;
455
456         if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) {
457                 pr_err("too small shared memory area\n");
458                 return ERR_PTR(-EINVAL);
459         }
460
461         va = memremap(paddr, size, MEMREMAP_WB);
462         if (!va) {
463                 pr_err("shared memory ioremap failed\n");
464                 return ERR_PTR(-EINVAL);
465         }
466         vaddr = (unsigned long)va;
467
468         /*
469          * If OP-TEE can work with unregistered SHM, we will use own pool
470          * for private shm
471          */
472         if (sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM) {
473                 rc = optee_shm_pool_alloc_pages();
474                 if (IS_ERR(rc))
475                         goto err_memunmap;
476                 priv_mgr = rc;
477         } else {
478                 const size_t sz = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE;
479
480                 rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, sz,
481                                                     3 /* 8 bytes aligned */);
482                 if (IS_ERR(rc))
483                         goto err_memunmap;
484                 priv_mgr = rc;
485
486                 vaddr += sz;
487                 paddr += sz;
488                 size -= sz;
489         }
490
491         rc = tee_shm_pool_mgr_alloc_res_mem(vaddr, paddr, size, PAGE_SHIFT);
492         if (IS_ERR(rc))
493                 goto err_free_priv_mgr;
494         dmabuf_mgr = rc;
495
496         rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
497         if (IS_ERR(rc))
498                 goto err_free_dmabuf_mgr;
499
500         *memremaped_shm = va;
501
502         return rc;
503
504 err_free_dmabuf_mgr:
505         tee_shm_pool_mgr_destroy(dmabuf_mgr);
506 err_free_priv_mgr:
507         tee_shm_pool_mgr_destroy(priv_mgr);
508 err_memunmap:
509         memunmap(va);
510         return rc;
511 }
512
513 /* Simple wrapper functions to be able to use a function pointer */
514 static void optee_smccc_smc(unsigned long a0, unsigned long a1,
515                             unsigned long a2, unsigned long a3,
516                             unsigned long a4, unsigned long a5,
517                             unsigned long a6, unsigned long a7,
518                             struct arm_smccc_res *res)
519 {
520         arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res);
521 }
522
523 static void optee_smccc_hvc(unsigned long a0, unsigned long a1,
524                             unsigned long a2, unsigned long a3,
525                             unsigned long a4, unsigned long a5,
526                             unsigned long a6, unsigned long a7,
527                             struct arm_smccc_res *res)
528 {
529         arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res);
530 }
531
532 static optee_invoke_fn *get_invoke_func(struct device_node *np)
533 {
534         const char *method;
535
536         pr_info("probing for conduit method from DT.\n");
537
538         if (of_property_read_string(np, "method", &method)) {
539                 pr_warn("missing \"method\" property\n");
540                 return ERR_PTR(-ENXIO);
541         }
542
543         if (!strcmp("hvc", method))
544                 return optee_smccc_hvc;
545         else if (!strcmp("smc", method))
546                 return optee_smccc_smc;
547
548         pr_warn("invalid \"method\" property: %s\n", method);
549         return ERR_PTR(-EINVAL);
550 }
551
552 static struct optee *optee_probe(struct device_node *np)
553 {
554         optee_invoke_fn *invoke_fn;
555         struct tee_shm_pool *pool;
556         struct optee *optee = NULL;
557         void *memremaped_shm = NULL;
558         struct tee_device *teedev;
559         u32 sec_caps;
560         int rc;
561
562         invoke_fn = get_invoke_func(np);
563         if (IS_ERR(invoke_fn))
564                 return (void *)invoke_fn;
565
566         if (!optee_msg_api_uid_is_optee_api(invoke_fn)) {
567                 pr_warn("api uid mismatch\n");
568                 return ERR_PTR(-EINVAL);
569         }
570
571         optee_msg_get_os_revision(invoke_fn);
572
573         if (!optee_msg_api_revision_is_compatible(invoke_fn)) {
574                 pr_warn("api revision mismatch\n");
575                 return ERR_PTR(-EINVAL);
576         }
577
578         if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) {
579                 pr_warn("capabilities mismatch\n");
580                 return ERR_PTR(-EINVAL);
581         }
582
583         /*
584          * We have no other option for shared memory, if secure world
585          * doesn't have any reserved memory we can use we can't continue.
586          */
587         if (!(sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM))
588                 return ERR_PTR(-EINVAL);
589
590         pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm, sec_caps);
591         if (IS_ERR(pool))
592                 return (void *)pool;
593
594         optee = kzalloc(sizeof(*optee), GFP_KERNEL);
595         if (!optee) {
596                 rc = -ENOMEM;
597                 goto err;
598         }
599
600         optee->invoke_fn = invoke_fn;
601         optee->sec_caps = sec_caps;
602
603         teedev = tee_device_alloc(&optee_desc, NULL, pool, optee);
604         if (IS_ERR(teedev)) {
605                 rc = PTR_ERR(teedev);
606                 goto err;
607         }
608         optee->teedev = teedev;
609
610         teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee);
611         if (IS_ERR(teedev)) {
612                 rc = PTR_ERR(teedev);
613                 goto err;
614         }
615         optee->supp_teedev = teedev;
616
617         rc = tee_device_register(optee->teedev);
618         if (rc)
619                 goto err;
620
621         rc = tee_device_register(optee->supp_teedev);
622         if (rc)
623                 goto err;
624
625         mutex_init(&optee->call_queue.mutex);
626         INIT_LIST_HEAD(&optee->call_queue.waiters);
627         optee_wait_queue_init(&optee->wait_queue);
628         optee_supp_init(&optee->supp);
629         optee->memremaped_shm = memremaped_shm;
630         optee->pool = pool;
631
632         optee_enable_shm_cache(optee);
633
634         if (optee->sec_caps & OPTEE_SMC_SEC_CAP_DYNAMIC_SHM)
635                 pr_info("dynamic shared memory is enabled\n");
636
637         rc = optee_enumerate_devices();
638         if (rc)
639                 goto err;
640
641         pr_info("initialized driver\n");
642         return optee;
643 err:
644         if (optee) {
645                 /*
646                  * tee_device_unregister() is safe to call even if the
647                  * devices hasn't been registered with
648                  * tee_device_register() yet.
649                  */
650                 tee_device_unregister(optee->supp_teedev);
651                 tee_device_unregister(optee->teedev);
652                 kfree(optee);
653         }
654         if (pool)
655                 tee_shm_pool_free(pool);
656         if (memremaped_shm)
657                 memunmap(memremaped_shm);
658         return ERR_PTR(rc);
659 }
660
661 static void optee_remove(struct optee *optee)
662 {
663         /*
664          * Ask OP-TEE to free all cached shared memory objects to decrease
665          * reference counters and also avoid wild pointers in secure world
666          * into the old shared memory range.
667          */
668         optee_disable_shm_cache(optee);
669
670         /*
671          * The two devices has to be unregistered before we can free the
672          * other resources.
673          */
674         tee_device_unregister(optee->supp_teedev);
675         tee_device_unregister(optee->teedev);
676
677         tee_shm_pool_free(optee->pool);
678         if (optee->memremaped_shm)
679                 memunmap(optee->memremaped_shm);
680         optee_wait_queue_exit(&optee->wait_queue);
681         optee_supp_uninit(&optee->supp);
682         mutex_destroy(&optee->call_queue.mutex);
683
684         kfree(optee);
685 }
686
687 static const struct of_device_id optee_match[] = {
688         { .compatible = "linaro,optee-tz" },
689         {},
690 };
691
692 static struct optee *optee_svc;
693
694 static int __init optee_driver_init(void)
695 {
696         struct device_node *fw_np;
697         struct device_node *np;
698         struct optee *optee;
699
700         /* Node is supposed to be below /firmware */
701         fw_np = of_find_node_by_name(NULL, "firmware");
702         if (!fw_np)
703                 return -ENODEV;
704
705         np = of_find_matching_node(fw_np, optee_match);
706         if (!np || !of_device_is_available(np)) {
707                 of_node_put(np);
708                 return -ENODEV;
709         }
710
711         optee = optee_probe(np);
712         of_node_put(np);
713
714         if (IS_ERR(optee))
715                 return PTR_ERR(optee);
716
717         optee_svc = optee;
718
719         return 0;
720 }
721 module_init(optee_driver_init);
722
723 static void __exit optee_driver_exit(void)
724 {
725         struct optee *optee = optee_svc;
726
727         optee_svc = NULL;
728         if (optee)
729                 optee_remove(optee);
730 }
731 module_exit(optee_driver_exit);
732
733 MODULE_AUTHOR("Linaro");
734 MODULE_DESCRIPTION("OP-TEE driver");
735 MODULE_SUPPORTED_DEVICE("");
736 MODULE_VERSION("1.0");
737 MODULE_LICENSE("GPL v2");