xref: /rk3399_ARM-atf/services/spd/opteed/opteed_main.c (revision 7944421ba4dfd3c49a26d525a884d8408ef127a8)
1 /*
2  * Copyright (c) 2013-2023, Arm Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 
8 /*******************************************************************************
9  * This is the Secure Payload Dispatcher (SPD). The dispatcher is meant to be a
10  * plug-in component to the Secure Monitor, registered as a runtime service. The
11  * SPD is expected to be a functional extension of the Secure Payload (SP) that
12  * executes in Secure EL1. The Secure Monitor will delegate all SMCs targeting
13  * the Trusted OS/Applications range to the dispatcher. The SPD will either
14  * handle the request locally or delegate it to the Secure Payload. It is also
15  * responsible for initialising and maintaining communication with the SP.
16  ******************************************************************************/
17 #include <assert.h>
18 #include <errno.h>
19 #include <inttypes.h>
20 #include <stddef.h>
21 
22 #include <arch_helpers.h>
23 #include <bl31/bl31.h>
24 #include <common/bl_common.h>
25 #include <common/debug.h>
26 #include <common/runtime_svc.h>
27 #include <lib/coreboot.h>
28 #include <lib/el3_runtime/context_mgmt.h>
29 #include <lib/optee_utils.h>
30 #include <lib/transfer_list.h>
31 #include <lib/xlat_tables/xlat_tables_v2.h>
32 #if OPTEE_ALLOW_SMC_LOAD
33 #include <libfdt.h>
34 #endif  /* OPTEE_ALLOW_SMC_LOAD */
35 #include <plat/common/platform.h>
36 #include <services/oem/chromeos/widevine_smc_handlers.h>
37 #include <tools_share/uuid.h>
38 
39 #include "opteed_private.h"
40 #include "teesmc_opteed.h"
41 
42 #if OPTEE_ALLOW_SMC_LOAD
43 static struct transfer_list_header *bl31_tl;
44 #endif
45 
46 /*******************************************************************************
47  * Address of the entrypoint vector table in OPTEE. It is
48  * initialised once on the primary core after a cold boot.
49  ******************************************************************************/
50 struct optee_vectors *optee_vector_table;
51 
52 /*******************************************************************************
53  * Array to keep track of per-cpu OPTEE state
54  ******************************************************************************/
55 optee_context_t opteed_sp_context[OPTEED_CORE_COUNT];
56 uint32_t opteed_rw;
57 
58 #if OPTEE_ALLOW_SMC_LOAD
59 static bool opteed_allow_load;
60 /* OP-TEE image loading service UUID */
61 DEFINE_SVC_UUID2(optee_image_load_uuid,
62 	0xb1eafba3, 0x5d31, 0x4612, 0xb9, 0x06,
63 	0xc4, 0xc7, 0xa4, 0xbe, 0x3c, 0xc0);
64 
65 #define OPTEED_FDT_SIZE 1024
66 static uint8_t fdt_buf[OPTEED_FDT_SIZE] __aligned(CACHE_WRITEBACK_GRANULE);
67 
68 #else
69 static int32_t opteed_init(void);
70 #endif
71 
72 uint64_t dual32to64(uint32_t high, uint32_t low)
73 {
74 	return ((uint64_t)high << 32) | low;
75 }
76 
77 /*******************************************************************************
78  * This function is the handler registered for S-EL1 interrupts by the
79  * OPTEED. It validates the interrupt and upon success arranges entry into
80  * the OPTEE at 'optee_fiq_entry()' for handling the interrupt.
81  ******************************************************************************/
82 static uint64_t opteed_sel1_interrupt_handler(uint32_t id,
83 					    uint32_t flags,
84 					    void *handle,
85 					    void *cookie)
86 {
87 	uint32_t linear_id;
88 	optee_context_t *optee_ctx;
89 
90 	/* Check the security state when the exception was generated */
91 	assert(get_interrupt_src_ss(flags) == NON_SECURE);
92 
93 	/* Sanity check the pointer to this cpu's context */
94 	assert(handle == cm_get_context(NON_SECURE));
95 
96 	/* Save the non-secure context before entering the OPTEE */
97 	cm_el1_sysregs_context_save(NON_SECURE);
98 
99 	/* Get a reference to this cpu's OPTEE context */
100 	linear_id = plat_my_core_pos();
101 	optee_ctx = &opteed_sp_context[linear_id];
102 	assert(&optee_ctx->cpu_ctx == cm_get_context(SECURE));
103 
104 	cm_set_elr_el3(SECURE, (uint64_t)&optee_vector_table->fiq_entry);
105 	cm_el1_sysregs_context_restore(SECURE);
106 	cm_set_next_eret_context(SECURE);
107 
108 	/*
109 	 * Tell the OPTEE that it has to handle an FIQ (synchronously).
110 	 * Also the instruction in normal world where the interrupt was
111 	 * generated is passed for debugging purposes. It is safe to
112 	 * retrieve this address from ELR_EL3 as the secure context will
113 	 * not take effect until el3_exit().
114 	 */
115 	SMC_RET1(&optee_ctx->cpu_ctx, read_elr_el3());
116 }
117 
118 /*******************************************************************************
119  * OPTEE Dispatcher setup. The OPTEED finds out the OPTEE entrypoint and type
120  * (aarch32/aarch64) if not already known and initialises the context for entry
121  * into OPTEE for its initialization.
122  ******************************************************************************/
123 static int32_t opteed_setup(void)
124 {
125 #if OPTEE_ALLOW_SMC_LOAD
126 	opteed_allow_load = true;
127 	INFO("Delaying OP-TEE setup until we receive an SMC call to load it\n");
128 	return 0;
129 #else
130 	entry_point_info_t *optee_ep_info;
131 	uint32_t linear_id;
132 	uint64_t arg0;
133 	uint64_t arg1;
134 	uint64_t arg2;
135 	uint64_t arg3;
136 	struct transfer_list_header *tl = NULL;
137 	struct transfer_list_entry *te = NULL;
138 	void *dt = NULL;
139 
140 	linear_id = plat_my_core_pos();
141 
142 	/*
143 	 * Get information about the Secure Payload (BL32) image. Its
144 	 * absence is a critical failure.  TODO: Add support to
145 	 * conditionally include the SPD service
146 	 */
147 	optee_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
148 	if (!optee_ep_info) {
149 		WARN("No OPTEE provided by BL2 boot loader, Booting device"
150 			" without OPTEE initialization. SMC`s destined for OPTEE"
151 			" will return SMC_UNK\n");
152 		return 1;
153 	}
154 
155 	/*
156 	 * If there's no valid entry point for SP, we return a non-zero value
157 	 * signalling failure initializing the service. We bail out without
158 	 * registering any handlers
159 	 */
160 	if (!optee_ep_info->pc)
161 		return 1;
162 
163 	if (TRANSFER_LIST &&
164 		optee_ep_info->args.arg1 == (TRANSFER_LIST_SIGNATURE |
165 					REGISTER_CONVENTION_VERSION_MASK)) {
166 		tl = (void *)optee_ep_info->args.arg3;
167 		if (transfer_list_check_header(tl) == TL_OPS_NON) {
168 			return 1;
169 		}
170 
171 		opteed_rw = GET_RW(optee_ep_info->spsr);
172 		te = transfer_list_find(tl, TL_TAG_FDT);
173 		dt = transfer_list_entry_data(te);
174 
175 		if (opteed_rw == OPTEE_AARCH64) {
176 			arg0 = (uint64_t)dt;
177 			arg2 = 0;
178 		} else {
179 			arg2 = (uint64_t)dt;
180 			arg0 = 0;
181 		}
182 
183 		arg1 = optee_ep_info->args.arg1;
184 		arg3 = optee_ep_info->args.arg3;
185 	} else {
186 		/* Default handoff arguments */
187 		opteed_rw = optee_ep_info->args.arg0;
188 		arg0 = optee_ep_info->args.arg1; /* opteed_pageable_part */
189 		arg1 = optee_ep_info->args.arg2; /* opteed_mem_limit */
190 		arg2 = optee_ep_info->args.arg3; /* dt_addr */
191 		arg3 = 0;
192 	}
193 
194 	opteed_init_optee_ep_state(optee_ep_info, opteed_rw, optee_ep_info->pc,
195 				arg0, arg1, arg2, arg3,
196 				&opteed_sp_context[linear_id]);
197 
198 	/*
199 	 * All OPTEED initialization done. Now register our init function with
200 	 * BL31 for deferred invocation
201 	 */
202 	bl31_register_bl32_init(&opteed_init);
203 
204 	return 0;
205 #endif  /* OPTEE_ALLOW_SMC_LOAD */
206 }
207 
208 /*******************************************************************************
209  * This function passes control to the OPTEE image (BL32) for the first time
210  * on the primary cpu after a cold boot. It assumes that a valid secure
211  * context has already been created by opteed_setup() which can be directly
212  * used.  It also assumes that a valid non-secure context has been
213  * initialised by PSCI so it does not need to save and restore any
214  * non-secure state. This function performs a synchronous entry into
215  * OPTEE. OPTEE passes control back to this routine through a SMC. This returns
216  * a non-zero value on success and zero on failure.
217  ******************************************************************************/
218 static int32_t
219 opteed_init_with_entry_point(entry_point_info_t *optee_entry_point)
220 {
221 	uint32_t linear_id = plat_my_core_pos();
222 	optee_context_t *optee_ctx = &opteed_sp_context[linear_id];
223 	uint64_t rc;
224 	assert(optee_entry_point);
225 
226 	cm_init_my_context(optee_entry_point);
227 
228 	/*
229 	 * Arrange for an entry into OPTEE. It will be returned via
230 	 * OPTEE_ENTRY_DONE case
231 	 */
232 	rc = opteed_synchronous_sp_entry(optee_ctx);
233 	assert(rc != 0);
234 
235 	return rc;
236 }
237 
238 #if !OPTEE_ALLOW_SMC_LOAD
239 static int32_t opteed_init(void)
240 {
241 	entry_point_info_t *optee_entry_point;
242 	/*
243 	 * Get information about the OP-TEE (BL32) image. Its
244 	 * absence is a critical failure.
245 	 */
246 	optee_entry_point = bl31_plat_get_next_image_ep_info(SECURE);
247 	return opteed_init_with_entry_point(optee_entry_point);
248 }
249 #endif  /* !OPTEE_ALLOW_SMC_LOAD */
250 
251 #if OPTEE_ALLOW_SMC_LOAD
252 #if COREBOOT
253 /*
254  * Adds a firmware/coreboot node with the coreboot table information to a device
255  * tree. Returns zero on success or if there is no coreboot table information;
256  * failure code otherwise.
257  */
258 static int add_coreboot_node(void *fdt)
259 {
260 	int ret;
261 	uint64_t coreboot_table_addr;
262 	uint32_t coreboot_table_size;
263 	struct {
264 		uint64_t addr;
265 		uint32_t size;
266 	} reg_node;
267 	coreboot_get_table_location(&coreboot_table_addr, &coreboot_table_size);
268 	if (!coreboot_table_addr || !coreboot_table_size) {
269 		WARN("Unable to get coreboot table location for device tree");
270 		return 0;
271 	}
272 	ret = fdt_begin_node(fdt, "firmware");
273 	if (ret)
274 		return ret;
275 
276 	ret = fdt_property(fdt, "ranges", NULL, 0);
277 	if (ret)
278 		return ret;
279 
280 	ret = fdt_begin_node(fdt, "coreboot");
281 	if (ret)
282 		return ret;
283 
284 	ret = fdt_property_string(fdt, "compatible", "coreboot");
285 	if (ret)
286 		return ret;
287 
288 	reg_node.addr = cpu_to_fdt64(coreboot_table_addr);
289 	reg_node.size = cpu_to_fdt32(coreboot_table_size);
290 	ret = fdt_property(fdt, "reg", &reg_node,
291 				sizeof(uint64_t) + sizeof(uint32_t));
292 	if (ret)
293 		return ret;
294 
295 	ret = fdt_end_node(fdt);
296 	if (ret)
297 		return ret;
298 
299 	return fdt_end_node(fdt);
300 }
301 #endif /* COREBOOT */
302 
303 #if CROS_WIDEVINE_SMC
304 /*
305  * Adds a options/widevine node with the widevine table information to a device
306  * tree. Returns zero on success or if there is no widevine table information;
307  * failure code otherwise.
308  */
309 static int add_options_widevine_node(void *fdt)
310 {
311 	int ret;
312 
313 	ret = fdt_begin_node(fdt, "options");
314 	if (ret)
315 		return ret;
316 
317 	ret = fdt_begin_node(fdt, "op-tee");
318 	if (ret)
319 		return ret;
320 
321 	ret = fdt_begin_node(fdt, "widevine");
322 	if (ret)
323 		return ret;
324 
325 	if (cros_oem_tpm_auth_pk.length) {
326 		ret = fdt_property(fdt, "tcg,tpm-auth-public-key",
327 				   cros_oem_tpm_auth_pk.buffer,
328 				   cros_oem_tpm_auth_pk.length);
329 		if (ret)
330 			return ret;
331 	}
332 
333 	if (cros_oem_huk.length) {
334 		ret = fdt_property(fdt, "op-tee,hardware-unique-key",
335 				   cros_oem_huk.buffer, cros_oem_huk.length);
336 		if (ret)
337 			return ret;
338 	}
339 
340 	if (cros_oem_rot.length) {
341 		ret = fdt_property(fdt, "google,widevine-root-of-trust-ecc-p256",
342 				   cros_oem_rot.buffer, cros_oem_rot.length);
343 		if (ret)
344 			return ret;
345 	}
346 
347 	ret = fdt_end_node(fdt);
348 	if (ret)
349 		return ret;
350 
351 	ret = fdt_end_node(fdt);
352 	if (ret)
353 		return ret;
354 
355 	return fdt_end_node(fdt);
356 }
357 #endif /* CROS_WIDEVINE_SMC */
358 
359 /*
360  * Creates a device tree for passing into OP-TEE. Currently is populated with
361  * the coreboot table address.
362  * Returns 0 on success, error code otherwise.
363  */
364 static int create_opteed_dt(void)
365 {
366 	int ret;
367 
368 	ret = fdt_create(fdt_buf, OPTEED_FDT_SIZE);
369 	if (ret)
370 		return ret;
371 
372 	ret = fdt_finish_reservemap(fdt_buf);
373 	if (ret)
374 		return ret;
375 
376 	ret = fdt_begin_node(fdt_buf, "");
377 	if (ret)
378 		return ret;
379 
380 #if COREBOOT
381 	ret = add_coreboot_node(fdt_buf);
382 	if (ret)
383 		return ret;
384 #endif /* COREBOOT */
385 
386 #if CROS_WIDEVINE_SMC
387 	ret = add_options_widevine_node(fdt_buf);
388 	if (ret)
389 		return ret;
390 #endif /* CROS_WIDEVINE_SMC */
391 
392 	ret = fdt_end_node(fdt_buf);
393 	if (ret)
394 		return ret;
395 
396 	return fdt_finish(fdt_buf);
397 }
398 
399 static int32_t create_smc_tl(const void *fdt, uint32_t fdt_sz)
400 {
401 #if TRANSFER_LIST
402 	bl31_tl = transfer_list_init((void *)(uintptr_t)FW_HANDOFF_BASE,
403 				FW_HANDOFF_SIZE);
404 	if (!bl31_tl) {
405 		ERROR("Failed to initialize Transfer List at 0x%lx\n",
406 		(unsigned long)FW_HANDOFF_BASE);
407 		return -1;
408 	}
409 
410 	if (!transfer_list_add(bl31_tl, TL_TAG_FDT, fdt_sz, fdt)) {
411 		return -1;
412 	}
413 	return 0;
414 #else
415 	return -1;
416 #endif
417 }
418 
419 /*******************************************************************************
420  * This function is responsible for handling the SMC that loads the OP-TEE
421  * binary image via a non-secure SMC call. It takes the size and physical
422  * address of the payload as parameters.
423  ******************************************************************************/
424 static int32_t opteed_handle_smc_load(uint64_t data_size, uint32_t data_pa)
425 {
426 	uintptr_t data_va = data_pa;
427 	uint64_t mapped_data_pa;
428 	uintptr_t mapped_data_va;
429 	uint64_t data_map_size;
430 	int32_t rc;
431 	optee_header_t *image_header;
432 	uint8_t *image_ptr;
433 	uint64_t target_pa;
434 	uint64_t target_end_pa;
435 	uint64_t image_pa;
436 	uintptr_t image_va;
437 	optee_image_t *curr_image;
438 	uintptr_t target_va;
439 	uint64_t target_size;
440 	entry_point_info_t optee_ep_info;
441 	uint32_t linear_id = plat_my_core_pos();
442 	uint64_t dt_addr = 0;
443 	uint64_t arg0 = 0;
444 	uint64_t arg1 = 0;
445 	uint64_t arg2 = 0;
446 	uint64_t arg3 = 0;
447 
448 	mapped_data_pa = page_align(data_pa, DOWN);
449 	mapped_data_va = mapped_data_pa;
450 	data_map_size = page_align(data_size + (mapped_data_pa - data_pa), UP);
451 
452 	/*
453 	 * We do not validate the passed in address because we are trusting the
454 	 * non-secure world at this point still.
455 	 */
456 	rc = mmap_add_dynamic_region(mapped_data_pa, mapped_data_va,
457 				     data_map_size, MT_MEMORY | MT_RO | MT_NS);
458 	if (rc != 0) {
459 		return rc;
460 	}
461 
462 	image_header = (optee_header_t *)data_va;
463 	if (image_header->magic != TEE_MAGIC_NUM_OPTEE ||
464 	    image_header->version != 2 || image_header->nb_images != 1) {
465 		mmap_remove_dynamic_region(mapped_data_va, data_map_size);
466 		return -EINVAL;
467 	}
468 
469 	image_ptr = (uint8_t *)data_va + sizeof(optee_header_t) +
470 			sizeof(optee_image_t);
471 	if (image_header->arch == 1) {
472 		opteed_rw = OPTEE_AARCH64;
473 	} else {
474 		opteed_rw = OPTEE_AARCH32;
475 	}
476 
477 	curr_image = &image_header->optee_image_list[0];
478 	image_pa = dual32to64(curr_image->load_addr_hi,
479 			      curr_image->load_addr_lo);
480 	image_va = image_pa;
481 	target_end_pa = image_pa + curr_image->size;
482 
483 	/* Now also map the memory we want to copy it to. */
484 	target_pa = page_align(image_pa, DOWN);
485 	target_va = target_pa;
486 	target_size = page_align(target_end_pa, UP) - target_pa;
487 
488 	rc = mmap_add_dynamic_region(target_pa, target_va, target_size,
489 				     MT_MEMORY | MT_RW | MT_SECURE);
490 	if (rc != 0) {
491 		mmap_remove_dynamic_region(mapped_data_va, data_map_size);
492 		return rc;
493 	}
494 
495 	INFO("Loaded OP-TEE via SMC: size %d addr 0x%" PRIx64 "\n",
496 	     curr_image->size, image_va);
497 
498 	memcpy((void *)image_va, image_ptr, curr_image->size);
499 	flush_dcache_range(target_pa, target_size);
500 
501 	mmap_remove_dynamic_region(mapped_data_va, data_map_size);
502 	mmap_remove_dynamic_region(target_va, target_size);
503 
504 	/* Save the non-secure state */
505 	cm_el1_sysregs_context_save(NON_SECURE);
506 
507 	rc = create_opteed_dt();
508 	if (rc) {
509 		ERROR("Failed device tree creation %d\n", rc);
510 		return rc;
511 	}
512 	dt_addr = (uint64_t)fdt_buf;
513 	flush_dcache_range(dt_addr, OPTEED_FDT_SIZE);
514 
515 	if (TRANSFER_LIST &&
516 	    !create_smc_tl((void *)dt_addr, OPTEED_FDT_SIZE)) {
517 		struct transfer_list_entry *te = NULL;
518 		void *dt = NULL;
519 
520 		te = transfer_list_find(bl31_tl, TL_TAG_FDT);
521 		dt = transfer_list_entry_data(te);
522 
523 		if (opteed_rw == OPTEE_AARCH64) {
524 			arg0 = (uint64_t)dt;
525 			arg2 = 0;
526 		} else {
527 			arg2 = (uint64_t)dt;
528 			arg0 = 0;
529 		}
530 		arg1 = TRANSFER_LIST_SIGNATURE |
531 			REGISTER_CONVENTION_VERSION_MASK;
532 		arg3 = (uint64_t)bl31_tl;
533 	} else {
534 		/* Default handoff arguments */
535 		arg2 = dt_addr;
536 	}
537 
538 	opteed_init_optee_ep_state(&optee_ep_info,
539 				   opteed_rw,
540 				   image_pa,
541 				   arg0,
542 				   arg1,
543 				   arg2,
544 				   arg3,
545 				   &opteed_sp_context[linear_id]);
546 	if (opteed_init_with_entry_point(&optee_ep_info) == 0) {
547 		rc = -EFAULT;
548 	}
549 
550 	/* Restore non-secure state */
551 	cm_el1_sysregs_context_restore(NON_SECURE);
552 	cm_set_next_eret_context(NON_SECURE);
553 
554 	return rc;
555 }
556 #endif  /* OPTEE_ALLOW_SMC_LOAD */
557 
558 /*******************************************************************************
559  * This function is responsible for handling all SMCs in the Trusted OS/App
560  * range from the non-secure state as defined in the SMC Calling Convention
561  * Document. It is also responsible for communicating with the Secure
562  * payload to delegate work and return results back to the non-secure
563  * state. Lastly it will also return any information that OPTEE needs to do
564  * the work assigned to it.
565  ******************************************************************************/
566 static uintptr_t opteed_smc_handler(uint32_t smc_fid,
567 			 u_register_t x1,
568 			 u_register_t x2,
569 			 u_register_t x3,
570 			 u_register_t x4,
571 			 void *cookie,
572 			 void *handle,
573 			 u_register_t flags)
574 {
575 	cpu_context_t *ns_cpu_context;
576 	uint32_t linear_id = plat_my_core_pos();
577 	optee_context_t *optee_ctx = &opteed_sp_context[linear_id];
578 	uint64_t rc;
579 
580 	/*
581 	 * Determine which security state this SMC originated from
582 	 */
583 
584 	if (is_caller_non_secure(flags)) {
585 #if OPTEE_ALLOW_SMC_LOAD
586 		if (opteed_allow_load && smc_fid == NSSMC_OPTEED_CALL_UID) {
587 			/* Provide the UUID of the image loading service. */
588 			SMC_UUID_RET(handle, optee_image_load_uuid);
589 		}
590 		if (smc_fid == NSSMC_OPTEED_CALL_LOAD_IMAGE) {
591 			/*
592 			 * TODO: Consider wiping the code for SMC loading from
593 			 * memory after it has been invoked similar to what is
594 			 * done under RECLAIM_INIT, but extended to happen
595 			 * later.
596 			 */
597 			if (!opteed_allow_load) {
598 				SMC_RET1(handle, -EPERM);
599 			}
600 
601 			opteed_allow_load = false;
602 			uint64_t data_size = dual32to64(x1, x2);
603 			uint64_t data_pa = dual32to64(x3, x4);
604 			if (!data_size || !data_pa) {
605 				/*
606 				 * This is invoked when the OP-TEE image didn't
607 				 * load correctly in the kernel but we want to
608 				 * block off loading of it later for security
609 				 * reasons.
610 				 */
611 				SMC_RET1(handle, -EINVAL);
612 			}
613 			SMC_RET1(handle, opteed_handle_smc_load(
614 					data_size, data_pa));
615 		}
616 #endif  /* OPTEE_ALLOW_SMC_LOAD */
617 		/*
618 		 * This is a fresh request from the non-secure client.
619 		 * The parameters are in x1 and x2. Figure out which
620 		 * registers need to be preserved, save the non-secure
621 		 * state and send the request to the secure payload.
622 		 */
623 		assert(handle == cm_get_context(NON_SECURE));
624 
625 		cm_el1_sysregs_context_save(NON_SECURE);
626 
627 		/*
628 		 * We are done stashing the non-secure context. Ask the
629 		 * OP-TEE to do the work now. If we are loading vi an SMC,
630 		 * then we also need to init this CPU context if not done
631 		 * already.
632 		 */
633 		if (optee_vector_table == NULL) {
634 			SMC_RET1(handle, -EINVAL);
635 		}
636 
637 		if (get_optee_pstate(optee_ctx->state) ==
638 		    OPTEE_PSTATE_UNKNOWN) {
639 			opteed_cpu_on_finish_handler(0);
640 		}
641 
642 		/*
643 		 * Verify if there is a valid context to use, copy the
644 		 * operation type and parameters to the secure context
645 		 * and jump to the fast smc entry point in the secure
646 		 * payload. Entry into S-EL1 will take place upon exit
647 		 * from this function.
648 		 */
649 		assert(&optee_ctx->cpu_ctx == cm_get_context(SECURE));
650 
651 		/* Set appropriate entry for SMC.
652 		 * We expect OPTEE to manage the PSTATE.I and PSTATE.F
653 		 * flags as appropriate.
654 		 */
655 		if (GET_SMC_TYPE(smc_fid) == SMC_TYPE_FAST) {
656 			cm_set_elr_el3(SECURE, (uint64_t)
657 					&optee_vector_table->fast_smc_entry);
658 		} else {
659 			cm_set_elr_el3(SECURE, (uint64_t)
660 					&optee_vector_table->yield_smc_entry);
661 		}
662 
663 		cm_el1_sysregs_context_restore(SECURE);
664 		cm_set_next_eret_context(SECURE);
665 
666 		write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx),
667 			      CTX_GPREG_X4,
668 			      read_ctx_reg(get_gpregs_ctx(handle),
669 					   CTX_GPREG_X4));
670 		write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx),
671 			      CTX_GPREG_X5,
672 			      read_ctx_reg(get_gpregs_ctx(handle),
673 					   CTX_GPREG_X5));
674 		write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx),
675 			      CTX_GPREG_X6,
676 			      read_ctx_reg(get_gpregs_ctx(handle),
677 					   CTX_GPREG_X6));
678 		/* Propagate hypervisor client ID */
679 		write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx),
680 			      CTX_GPREG_X7,
681 			      read_ctx_reg(get_gpregs_ctx(handle),
682 					   CTX_GPREG_X7));
683 
684 		SMC_RET4(&optee_ctx->cpu_ctx, smc_fid, x1, x2, x3);
685 	}
686 
687 	/*
688 	 * Returning from OPTEE
689 	 */
690 
691 	switch (smc_fid) {
692 	/*
693 	 * OPTEE has finished initialising itself after a cold boot
694 	 */
695 	case TEESMC_OPTEED_RETURN_ENTRY_DONE:
696 		/*
697 		 * Stash the OPTEE entry points information. This is done
698 		 * only once on the primary cpu
699 		 */
700 		assert(optee_vector_table == NULL);
701 		optee_vector_table = (optee_vectors_t *) x1;
702 
703 		if (optee_vector_table) {
704 			set_optee_pstate(optee_ctx->state, OPTEE_PSTATE_ON);
705 
706 			/*
707 			 * OPTEE has been successfully initialized.
708 			 * Register power management hooks with PSCI
709 			 */
710 			psci_register_spd_pm_hook(&opteed_pm);
711 
712 			/*
713 			 * Register an interrupt handler for S-EL1 interrupts
714 			 * when generated during code executing in the
715 			 * non-secure state.
716 			 */
717 			flags = 0;
718 			set_interrupt_rm_flag(flags, NON_SECURE);
719 			rc = register_interrupt_type_handler(INTR_TYPE_S_EL1,
720 						opteed_sel1_interrupt_handler,
721 						flags);
722 			if (rc)
723 				panic();
724 		}
725 
726 		/*
727 		 * OPTEE reports completion. The OPTEED must have initiated
728 		 * the original request through a synchronous entry into
729 		 * OPTEE. Jump back to the original C runtime context.
730 		 */
731 		opteed_synchronous_sp_exit(optee_ctx, x1);
732 		break;
733 
734 
735 	/*
736 	 * These function IDs is used only by OP-TEE to indicate it has
737 	 * finished:
738 	 * 1. turning itself on in response to an earlier psci
739 	 *    cpu_on request
740 	 * 2. resuming itself after an earlier psci cpu_suspend
741 	 *    request.
742 	 */
743 	case TEESMC_OPTEED_RETURN_ON_DONE:
744 	case TEESMC_OPTEED_RETURN_RESUME_DONE:
745 
746 
747 	/*
748 	 * These function IDs is used only by the SP to indicate it has
749 	 * finished:
750 	 * 1. suspending itself after an earlier psci cpu_suspend
751 	 *    request.
752 	 * 2. turning itself off in response to an earlier psci
753 	 *    cpu_off request.
754 	 */
755 	case TEESMC_OPTEED_RETURN_OFF_DONE:
756 	case TEESMC_OPTEED_RETURN_SUSPEND_DONE:
757 	case TEESMC_OPTEED_RETURN_SYSTEM_OFF_DONE:
758 	case TEESMC_OPTEED_RETURN_SYSTEM_RESET_DONE:
759 
760 		/*
761 		 * OPTEE reports completion. The OPTEED must have initiated the
762 		 * original request through a synchronous entry into OPTEE.
763 		 * Jump back to the original C runtime context, and pass x1 as
764 		 * return value to the caller
765 		 */
766 		opteed_synchronous_sp_exit(optee_ctx, x1);
767 		break;
768 
769 	/*
770 	 * OPTEE is returning from a call or being preempted from a call, in
771 	 * either case execution should resume in the normal world.
772 	 */
773 	case TEESMC_OPTEED_RETURN_CALL_DONE:
774 		/*
775 		 * This is the result from the secure client of an
776 		 * earlier request. The results are in x0-x3. Copy it
777 		 * into the non-secure context, save the secure state
778 		 * and return to the non-secure state.
779 		 */
780 		assert(handle == cm_get_context(SECURE));
781 		cm_el1_sysregs_context_save(SECURE);
782 
783 		/* Get a reference to the non-secure context */
784 		ns_cpu_context = cm_get_context(NON_SECURE);
785 		assert(ns_cpu_context);
786 
787 		/* Restore non-secure state */
788 		cm_el1_sysregs_context_restore(NON_SECURE);
789 		cm_set_next_eret_context(NON_SECURE);
790 
791 		SMC_RET4(ns_cpu_context, x1, x2, x3, x4);
792 
793 	/*
794 	 * OPTEE has finished handling a S-EL1 FIQ interrupt. Execution
795 	 * should resume in the normal world.
796 	 */
797 	case TEESMC_OPTEED_RETURN_FIQ_DONE:
798 		/* Get a reference to the non-secure context */
799 		ns_cpu_context = cm_get_context(NON_SECURE);
800 		assert(ns_cpu_context);
801 
802 		/*
803 		 * Restore non-secure state. There is no need to save the
804 		 * secure system register context since OPTEE was supposed
805 		 * to preserve it during S-EL1 interrupt handling.
806 		 */
807 		cm_el1_sysregs_context_restore(NON_SECURE);
808 		cm_set_next_eret_context(NON_SECURE);
809 
810 		SMC_RET0((uint64_t) ns_cpu_context);
811 
812 	default:
813 		panic();
814 	}
815 }
816 
817 /* Define an OPTEED runtime service descriptor for fast SMC calls */
818 DECLARE_RT_SVC(
819 	opteed_fast,
820 
821 	OEN_TOS_START,
822 	OEN_TOS_END,
823 	SMC_TYPE_FAST,
824 	opteed_setup,
825 	opteed_smc_handler
826 );
827 
828 /* Define an OPTEED runtime service descriptor for yielding SMC calls */
829 DECLARE_RT_SVC(
830 	opteed_std,
831 
832 	OEN_TOS_START,
833 	OEN_TOS_END,
834 	SMC_TYPE_YIELD,
835 	NULL,
836 	opteed_smc_handler
837 );
838