xref: /optee_os/core/arch/arm/kernel/thread_a32.S (revision 5ff5a48e03014667c9e64607db697691fad5ac9a)
1/* SPDX-License-Identifier: BSD-2-Clause */
2/*
3 * Copyright (c) 2016-2017, Linaro Limited
4 * Copyright (c) 2014, STMicroelectronics International N.V.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright notice,
11 * this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright notice,
14 * this list of conditions and the following disclaimer in the documentation
15 * and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
21 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <arm32_macros.S>
31#include <arm.h>
32#include <asm-defines.h>
33#include <asm.S>
34#include <keep.h>
35#include <kernel/abort.h>
36#include <kernel/thread_defs.h>
37#include <kernel/unwind.h>
38#include <mm/core_mmu.h>
39#include <sm/optee_smc.h>
40#include <sm/teesmc_opteed.h>
41#include <sm/teesmc_opteed_macros.h>
42
43#include "thread_private.h"
44
45	.macro cmp_spsr_user_mode reg:req
46		/*
47		 * We're only testing the lower 4 bits as bit 5 (0x10)
48		 * always is set.
49		 */
50		tst	\reg, #0x0f
51	.endm
52
53LOCAL_FUNC vector_std_smc_entry , :
54UNWIND(	.fnstart)
55UNWIND(	.cantunwind)
56	push	{r0-r7}
57	mov	r0, sp
58	bl	thread_handle_std_smc
59	/*
60	 * Normally thread_handle_std_smc() should return via
61	 * thread_exit(), thread_rpc(), but if thread_handle_std_smc()
62	 * hasn't switched stack (error detected) it will do a normal "C"
63	 * return.
64	 */
65	pop	{r1-r8}
66	ldr	r0, =TEESMC_OPTEED_RETURN_CALL_DONE
67	smc	#0
68	b	.	/* SMC should not return */
69UNWIND(	.fnend)
70END_FUNC vector_std_smc_entry
71
72LOCAL_FUNC vector_fast_smc_entry , :
73UNWIND(	.fnstart)
74UNWIND(	.cantunwind)
75	push	{r0-r7}
76	mov	r0, sp
77	bl	thread_handle_fast_smc
78	pop	{r1-r8}
79	ldr	r0, =TEESMC_OPTEED_RETURN_CALL_DONE
80	smc	#0
81	b	.	/* SMC should not return */
82UNWIND(	.fnend)
83END_FUNC vector_fast_smc_entry
84
85LOCAL_FUNC vector_fiq_entry , :
86UNWIND(	.fnstart)
87UNWIND(	.cantunwind)
88 	/* Secure Monitor received a FIQ and passed control to us. */
89	bl	thread_check_canaries
90	ldr	lr, =thread_nintr_handler_ptr
91 	ldr	lr, [lr]
92 	blx	lr
93	mov	r1, r0
94	ldr	r0, =TEESMC_OPTEED_RETURN_FIQ_DONE
95	smc	#0
96	b	.	/* SMC should not return */
97UNWIND(	.fnend)
98END_FUNC vector_fiq_entry
99
100LOCAL_FUNC vector_cpu_on_entry , :
101UNWIND(	.fnstart)
102UNWIND(	.cantunwind)
103	ldr	lr, =thread_cpu_on_handler_ptr
104	ldr	lr, [lr]
105	blx	lr
106	mov	r1, r0
107	ldr	r0, =TEESMC_OPTEED_RETURN_ON_DONE
108	smc	#0
109	b	.	/* SMC should not return */
110UNWIND(	.fnend)
111END_FUNC vector_cpu_on_entry
112
113LOCAL_FUNC vector_cpu_off_entry , :
114UNWIND(	.fnstart)
115UNWIND(	.cantunwind)
116	ldr	lr, =thread_cpu_off_handler_ptr
117	ldr	lr, [lr]
118	blx	lr
119	mov	r1, r0
120	ldr	r0, =TEESMC_OPTEED_RETURN_OFF_DONE
121	smc	#0
122	b	.	/* SMC should not return */
123UNWIND(	.fnend)
124END_FUNC vector_cpu_off_entry
125
126LOCAL_FUNC vector_cpu_suspend_entry , :
127UNWIND(	.fnstart)
128UNWIND(	.cantunwind)
129	ldr	lr, =thread_cpu_suspend_handler_ptr
130	ldr	lr, [lr]
131	blx	lr
132	mov	r1, r0
133	ldr	r0, =TEESMC_OPTEED_RETURN_SUSPEND_DONE
134	smc	#0
135	b	.	/* SMC should not return */
136UNWIND(	.fnend)
137END_FUNC vector_cpu_suspend_entry
138
139LOCAL_FUNC vector_cpu_resume_entry , :
140UNWIND(	.fnstart)
141UNWIND(	.cantunwind)
142	ldr	lr, =thread_cpu_resume_handler_ptr
143	ldr	lr, [lr]
144	blx	lr
145	mov	r1, r0
146	ldr	r0, =TEESMC_OPTEED_RETURN_RESUME_DONE
147	smc	#0
148	b	.	/* SMC should not return */
149UNWIND(	.fnend)
150END_FUNC vector_cpu_resume_entry
151
152LOCAL_FUNC vector_system_off_entry , :
153UNWIND(	.fnstart)
154UNWIND(	.cantunwind)
155	ldr	lr, =thread_system_off_handler_ptr
156	ldr	lr, [lr]
157	blx	lr
158	mov	r1, r0
159	ldr	r0, =TEESMC_OPTEED_RETURN_SYSTEM_OFF_DONE
160	smc	#0
161	b	.	/* SMC should not return */
162UNWIND(	.fnend)
163END_FUNC vector_system_off_entry
164
165LOCAL_FUNC vector_system_reset_entry , :
166UNWIND(	.fnstart)
167UNWIND(	.cantunwind)
168	ldr	lr, =thread_system_reset_handler_ptr
169	ldr	lr, [lr]
170	blx	lr
171	mov	r1, r0
172	ldr	r0, =TEESMC_OPTEED_RETURN_SYSTEM_RESET_DONE
173	smc	#0
174	b	.	/* SMC should not return */
175UNWIND(	.fnend)
176END_FUNC vector_system_reset_entry
177
178/*
179 * Vector table supplied to ARM Trusted Firmware (ARM-TF) at
180 * initialization.  Also used when compiled with the internal monitor, but
181 * the cpu_*_entry and system_*_entry are not used then.
182 *
183 * Note that ARM-TF depends on the layout of this vector table, any change
184 * in layout has to be synced with ARM-TF.
185 */
186FUNC thread_vector_table , :
187UNWIND(	.fnstart)
188UNWIND(	.cantunwind)
189	b	vector_std_smc_entry
190	b	vector_fast_smc_entry
191	b	vector_cpu_on_entry
192	b	vector_cpu_off_entry
193	b	vector_cpu_resume_entry
194	b	vector_cpu_suspend_entry
195	b	vector_fiq_entry
196	b	vector_system_off_entry
197	b	vector_system_reset_entry
198UNWIND(	.fnend)
199END_FUNC thread_vector_table
200KEEP_PAGER thread_vector_table
201
202FUNC thread_set_abt_sp , :
203UNWIND(	.fnstart)
204UNWIND(	.cantunwind)
205	mrs	r1, cpsr
206	cps	#CPSR_MODE_ABT
207	mov	sp, r0
208	msr	cpsr, r1
209	bx	lr
210UNWIND(	.fnend)
211END_FUNC thread_set_abt_sp
212
213FUNC thread_set_und_sp , :
214UNWIND(	.fnstart)
215UNWIND(	.cantunwind)
216	mrs	r1, cpsr
217	cps	#CPSR_MODE_UND
218	mov	sp, r0
219	msr	cpsr, r1
220	bx	lr
221UNWIND(	.fnend)
222END_FUNC thread_set_und_sp
223
224FUNC thread_set_irq_sp , :
225UNWIND(	.fnstart)
226UNWIND(	.cantunwind)
227	mrs	r1, cpsr
228	cps	#CPSR_MODE_IRQ
229	mov	sp, r0
230	msr	cpsr, r1
231	bx	lr
232UNWIND(	.fnend)
233END_FUNC thread_set_irq_sp
234
235FUNC thread_set_fiq_sp , :
236UNWIND(	.fnstart)
237UNWIND(	.cantunwind)
238	mrs	r1, cpsr
239	cps	#CPSR_MODE_FIQ
240	mov	sp, r0
241	msr	cpsr, r1
242	bx	lr
243UNWIND(	.fnend)
244END_FUNC thread_set_fiq_sp
245
246/* void thread_resume(struct thread_ctx_regs *regs) */
247FUNC thread_resume , :
248UNWIND(	.fnstart)
249UNWIND(	.cantunwind)
250	add	r12, r0, #(13 * 4)	/* Restore registers r0-r12 later */
251
252	cps	#CPSR_MODE_SYS
253	ldm	r12!, {sp, lr}
254
255	cps	#CPSR_MODE_SVC
256	ldm	r12!, {r1, sp, lr}
257	msr	spsr_fsxc, r1
258
259	ldm	r12, {r1, r2}
260
261	/*
262	 * Switching to some other mode than SVC as we need to set spsr in
263	 * order to return into the old state properly and it may be SVC
264	 * mode we're returning to.
265	 */
266	cps	#CPSR_MODE_ABT
267	cmp_spsr_user_mode r2
268	mov	lr, r1
269	msr	spsr_fsxc, r2
270	ldm	r0, {r0-r12}
271	movnes	pc, lr
272	b	eret_to_user_mode
273UNWIND(	.fnend)
274END_FUNC thread_resume
275
276/*
277 * Disables IRQ and FIQ and saves state of thread in fiq mode which has
278 * the banked r8-r12 registers, returns original CPSR.
279 */
280LOCAL_FUNC thread_save_state_fiq , :
281UNWIND(	.fnstart)
282UNWIND(	.cantunwind)
283	mov	r9, lr
284
285	/*
286	 * Uses stack for temporary storage, while storing needed
287	 * context in the thread context struct.
288	 */
289
290	mrs	r8, cpsr
291
292	cpsid	aif			/* Disable Async abort, IRQ and FIQ */
293
294	push	{r4-r7}
295	push	{r0-r3}
296
297	mrs	r6, cpsr		/* Save current CPSR */
298
299	bl	thread_get_ctx_regs
300
301	pop	{r1-r4}			/* r0-r3 pushed above */
302	stm	r0!, {r1-r4}
303	pop	{r1-r4}			/* r4-r7 pushed above */
304	stm	r0!, {r1-r4}
305
306	cps     #CPSR_MODE_SYS
307	stm	r0!, {r8-r12}
308	stm     r0!, {sp, lr}
309
310	cps     #CPSR_MODE_SVC
311	mrs     r1, spsr
312	stm     r0!, {r1, sp, lr}
313
314	/* back to fiq mode */
315	orr	r6, r6, #ARM32_CPSR_FIA	/* Disable Async abort, IRQ and FIQ */
316	msr	cpsr, r6		/* Restore mode */
317
318	mov	r0, r8			/* Return original CPSR */
319	bx	r9
320UNWIND(	.fnend)
321END_FUNC thread_save_state_fiq
322
323/*
324 * Disables IRQ and FIQ and saves state of thread, returns original
325 * CPSR.
326 */
327LOCAL_FUNC thread_save_state , :
328UNWIND(	.fnstart)
329UNWIND(	.cantunwind)
330	push	{r12, lr}
331	/*
332	 * Uses stack for temporary storage, while storing needed
333	 * context in the thread context struct.
334	 */
335
336	mrs	r12, cpsr
337
338	cpsid	aif			/* Disable Async abort, IRQ and FIQ */
339
340	push	{r4-r7}
341	push	{r0-r3}
342
343	mov	r5, r12			/* Save CPSR in a preserved register */
344	mrs	r6, cpsr		/* Save current CPSR */
345
346	bl	thread_get_ctx_regs
347
348	pop	{r1-r4}			/* r0-r3 pushed above */
349	stm	r0!, {r1-r4}
350	pop	{r1-r4}			/* r4-r7 pushed above */
351	stm	r0!, {r1-r4}
352	stm	r0!, {r8-r11}
353
354	pop	{r12, lr}
355	stm	r0!, {r12}
356
357        cps     #CPSR_MODE_SYS
358        stm     r0!, {sp, lr}
359
360        cps     #CPSR_MODE_SVC
361        mrs     r1, spsr
362        stm     r0!, {r1, sp, lr}
363
364	orr	r6, r6, #ARM32_CPSR_FIA	/* Disable Async abort, IRQ and FIQ */
365	msr	cpsr, r6		/* Restore mode */
366
367	mov	r0, r5			/* Return original CPSR */
368	bx	lr
369UNWIND(	.fnend)
370END_FUNC thread_save_state
371
372FUNC thread_std_smc_entry , :
373UNWIND(	.fnstart)
374UNWIND(	.cantunwind)
375	/* Pass r0-r7 in a struct thread_smc_args */
376	push	{r0-r7}
377	mov	r0, sp
378	bl	__thread_std_smc_entry
379	/*
380	 * Load the returned r0-r3 into preserved registers and skip the
381	 * "returned" r4-r7 since they will not be returned to normal
382	 * world.
383	 */
384	pop	{r4-r7}
385	add	sp, #(4 * 4)
386
387	/* Disable interrupts before switching to temporary stack */
388	cpsid	aif
389	bl	thread_get_tmp_sp
390	mov	sp, r0
391
392	bl	thread_state_free
393
394	ldr	r0, =TEESMC_OPTEED_RETURN_CALL_DONE
395	mov	r1, r4
396	mov	r2, r5
397	mov	r3, r6
398	mov	r4, r7
399	smc	#0
400	b	.	/* SMC should not return */
401UNWIND(	.fnend)
402END_FUNC thread_std_smc_entry
403
404
405/* void thread_rpc(uint32_t rv[THREAD_RPC_NUM_ARGS]) */
406FUNC thread_rpc , :
407/*
408 * r0-r2 are used to pass parameters to normal world
409 * r0-r5 are used to pass return vaule back from normal world
410 *
411 * note that r3 is used to pass "resume information", that is, which
412 * thread it is that should resume.
413 *
414 * Since the this function is following AAPCS we need to preserve r4-r5
415 * which are otherwise modified when returning back from normal world.
416 */
417UNWIND(	.fnstart)
418	push	{r4-r5, lr}
419UNWIND(	.save	{r4-r5, lr})
420	push	{r0}
421UNWIND(	.save	{r0})
422
423	bl	thread_save_state
424	mov	r4, r0			/* Save original CPSR */
425
426	/*
427 	 * Switch to temporary stack and SVC mode. Save CPSR to resume into.
428	 */
429	bl	thread_get_tmp_sp
430	ldr	r5, [sp]		/* Get pointer to rv[] */
431	cps	#CPSR_MODE_SVC		/* Change to SVC mode */
432	mov	sp, r0			/* Switch to tmp stack */
433
434	mov	r0, #THREAD_FLAGS_COPY_ARGS_ON_RETURN
435	mov	r1, r4			/* CPSR to restore */
436	ldr	r2, =.thread_rpc_return
437	bl	thread_state_suspend
438	mov	r4, r0			/* Supply thread index */
439	ldr	r0, =TEESMC_OPTEED_RETURN_CALL_DONE
440	ldm	r5, {r1-r3}		/* Load rv[] into r0-r2 */
441	smc	#0
442	b	.	/* SMC should not return */
443
444.thread_rpc_return:
445	/*
446	 * At this point has the stack pointer been restored to the value
447	 * it had when thread_save_state() was called above.
448	 *
449	 * Jumps here from thread_resume above when RPC has returned. The
450	 * IRQ and FIQ bits are restored to what they where when this
451	 * function was originally entered.
452	 */
453	pop	{r12}			/* Get pointer to rv[] */
454	stm	r12, {r0-r5}		/* Store r0-r5 into rv[] */
455	pop	{r4-r5, pc}
456UNWIND(	.fnend)
457END_FUNC thread_rpc
458KEEP_PAGER thread_rpc
459
460FUNC thread_init_vbar , :
461UNWIND(	.fnstart)
462	/* Set vector (VBAR) */
463	ldr	r0, =thread_vect_table
464	write_vbar r0
465	bx	lr
466UNWIND(	.fnend)
467END_FUNC thread_init_vbar
468KEEP_PAGER thread_init_vbar
469
470/*
471 * Below are low level routines handling entry and return from user mode.
472 *
473 * thread_enter_user_mode() saves all that registers user mode can change
474 * so kernel mode can restore needed registers when resuming execution
475 * after the call to thread_enter_user_mode() has returned.
476 * thread_enter_user_mode() doesn't return directly since it enters user
477 * mode instead, it's thread_unwind_user_mode() that does the
478 * returning by restoring the registers saved by thread_enter_user_mode().
479 *
480 * There's three ways for thread_enter_user_mode() to return to caller,
481 * user TA calls utee_return, user TA calls utee_panic or through an abort.
482 *
483 * Calls to utee_return or utee_panic are handled as:
484 * thread_svc_handler() -> tee_svc_handler() ->	tee_svc_do_call() which
485 * calls syscall_return() or syscall_panic().
486 *
487 * These function calls returns normally except thread_svc_handler() which
488 * which is an exception handling routine so it reads return address and
489 * SPSR to restore from the stack. syscall_return() and syscall_panic()
490 * changes return address and SPSR used by thread_svc_handler() to instead of
491 * returning into user mode as with other syscalls it returns into
492 * thread_unwind_user_mode() in kernel mode instead.  When
493 * thread_svc_handler() returns the stack pointer at the point where
494 * thread_enter_user_mode() left it so this is where
495 * thread_unwind_user_mode() can operate.
496 *
497 * Aborts are handled in a similar way but by thread_abort_handler()
498 * instead, when the pager sees that it's an abort from user mode that
499 * can't be handled it updates SPSR and return address used by
500 * thread_abort_handler() to return into thread_unwind_user_mode()
501 * instead.
502 */
503
504/*
505 * uint32_t __thread_enter_user_mode(unsigned long a0, unsigned long a1,
506 *               unsigned long a2, unsigned long a3, unsigned long user_sp,
507 *               unsigned long user_func, unsigned long spsr,
508 *               uint32_t *exit_status0, uint32_t *exit_status1)
509 *
510 */
511FUNC __thread_enter_user_mode , :
512UNWIND(	.fnstart)
513UNWIND(	.cantunwind)
514	/*
515	 * Save all registers to allow syscall_return() to resume execution
516	 * as if this function would have returned. This is also used in
517	 * syscall_panic().
518	 *
519	 * If stack usage of this function is changed
520	 * thread_unwind_user_mode() has to be updated.
521	 */
522	push    {r4-r12,lr}
523
524	ldr     r4, [sp, #(10 * 0x4)]   /* user stack pointer */
525	ldr     r5, [sp, #(11 * 0x4)]   /* user function */
526	ldr     r6, [sp, #(12 * 0x4)]   /* spsr */
527
528	/*
529	 * Save old user sp and set new user sp.
530	 */
531	cps	#CPSR_MODE_SYS
532	mov	r7, sp
533	mov     sp, r4
534	cps	#CPSR_MODE_SVC
535	push	{r7,r8}
536
537	/* Prepare user mode entry via eret_to_user_mode */
538	cpsid	aif
539	msr     spsr_fsxc, r6
540	mov	lr, r5
541
542	b	eret_to_user_mode
543UNWIND(	.fnend)
544END_FUNC __thread_enter_user_mode
545
546/*
547 * void thread_unwind_user_mode(uint32_t ret, uint32_t exit_status0,
548 *              uint32_t exit_status1);
549 * See description in thread.h
550 */
551FUNC thread_unwind_user_mode , :
552UNWIND(	.fnstart)
553UNWIND(	.cantunwind)
554	ldr     ip, [sp, #(15 * 0x4)]   /* &ctx->panicked */
555	str	r1, [ip]
556	ldr     ip, [sp, #(16 * 0x4)]   /* &ctx->panic_code */
557	str	r2, [ip]
558
559	/* Restore old user sp */
560	pop	{r4,r7}
561	cps	#CPSR_MODE_SYS
562	mov	sp, r4
563	cps	#CPSR_MODE_SVC
564
565	pop     {r4-r12,pc}	/* Match the push in thread_enter_user_mode()*/
566UNWIND(	.fnend)
567END_FUNC thread_unwind_user_mode
568
569	.macro maybe_restore_mapping
570		/*
571		 * This macro is a bit hard to read due to all the ifdefs,
572		 * we're testing for two different configs which makes four
573		 * different combinations.
574		 *
575		 * - With LPAE, and then some extra code if with
576		 *   CFG_CORE_UNMAP_CORE_AT_EL0
577		 * - Without LPAE, and then some extra code if with
578		 *   CFG_CORE_UNMAP_CORE_AT_EL0
579		 */
580
581		/*
582		 * At this point we can't rely on any memory being writable
583		 * yet, so we're using TPIDRPRW to store r0, and if with
584		 * LPAE TPIDRURO to store r1 too.
585		 */
586		write_tpidrprw r0
587
588#ifdef CFG_WITH_LPAE
589		write_tpidruro r1
590
591		read_ttbr0_64bit r0, r1
592		tst	r1, #BIT(TTBR_ASID_SHIFT - 32)
593		beq	11f
594
595#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
596		/*
597		 * Update the mapping to use the full kernel mode mapping.
598		 * Since the translation table could reside above 4GB we'll
599		 * have to use 64-bit arithmetics.
600		 */
601		subs	r0, r0, #CORE_MMU_L1_TBL_OFFSET
602		sbc	r1, r1, #0
603#endif
604		bic	r1, r1, #BIT(TTBR_ASID_SHIFT - 32)
605		write_ttbr0_64bit r0, r1
606		isb
607
608#else /*!CFG_WITH_LPAE*/
609		read_contextidr r0
610		tst	r0, #1
611		beq	11f
612
613		/* Update the mapping to use the full kernel mode mapping. */
614		bic	r0, r0, #1
615		write_contextidr r0
616		isb
617#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
618		read_ttbr1 r0
619		sub	r0, r0, #CORE_MMU_L1_TBL_OFFSET
620		write_ttbr1 r0
621		isb
622#endif
623
624#endif /*!CFG_WITH_LPAE*/
625
626#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
627		ldr	r0, =thread_vect_table
628		write_vbar r0
629		isb
630
631	11:	/*
632		 * The PC is adjusted unconditionally to guard against the
633		 * case there was an FIQ just before we did the "cpsid aif".
634		 */
635		ldr	r0, =22f
636		bx	r0
637	22:
638#else
639	11:
640#endif
641		read_tpidrprw r0
642#ifdef CFG_WITH_LPAE
643		read_tpidruro r1
644#endif
645	.endm
646
647/* The handler of native interrupt. */
648.macro	native_intr_handler mode:req
649	cpsid	aif
650	maybe_restore_mapping
651
652	/*
653	 * FIQ and IRQ have a +4 offset for lr compared to preferred return
654	 * address
655	 */
656	sub     lr, lr, #4
657
658	/*
659	 * We're always saving {r0-r3}. In IRQ mode we're saving r12 also.
660	 * In FIQ mode we're saving the banked fiq registers {r8-r12} FIQ
661	 * because the secure monitor doesn't save those. The treatment of
662	 * the banked fiq registers is somewhat analogous to the lazy save
663	 * of VFP registers.
664	 */
665	.ifc	\mode\(),fiq
666	push	{r0-r3, r8-r12, lr}
667	.else
668	push	{r0-r3, r12, lr}
669	.endif
670
671	bl	thread_check_canaries
672	ldr	lr, =thread_nintr_handler_ptr
673	ldr	lr, [lr]
674	blx	lr
675
676	mrs	r0, spsr
677	cmp_spsr_user_mode r0
678
679	.ifc	\mode\(),fiq
680	pop	{r0-r3, r8-r12, lr}
681	.else
682	pop	{r0-r3, r12, lr}
683	.endif
684
685	movnes	pc, lr
686	b	eret_to_user_mode
687.endm
688
689/* The handler of foreign interrupt. */
690.macro foreign_intr_handler mode:req
691	cpsid	aif
692	maybe_restore_mapping
693
694	sub	lr, lr, #4
695	push	{lr}
696	push	{r12}
697
698	.ifc	\mode\(),fiq
699	bl	thread_save_state_fiq
700	.else
701	bl	thread_save_state
702	.endif
703
704	mov	r0, #THREAD_FLAGS_EXIT_ON_FOREIGN_INTR
705	mrs	r1, spsr
706	pop	{r12}
707	pop	{r2}
708	blx	thread_state_suspend
709	mov	r4, r0		/* Supply thread index */
710
711	/*
712	 * Switch to SVC mode and copy current stack pointer as it already
713	 * is the tmp stack.
714	 */
715	mov	r0, sp
716	cps	#CPSR_MODE_SVC
717	mov	sp, r0
718
719	ldr	r0, =TEESMC_OPTEED_RETURN_CALL_DONE
720	ldr	r1, =OPTEE_SMC_RETURN_RPC_FOREIGN_INTR
721	mov	r2, #0
722	mov	r3, #0
723	/* r4 is already filled in above */
724	smc	#0
725	b	.	/* SMC should not return */
726.endm
727
728	.section .text.thread_vect_table
729        .align	5
730FUNC thread_vect_table , :
731UNWIND(	.fnstart)
732UNWIND(	.cantunwind)
733	b	.			/* Reset			*/
734	b	thread_und_handler	/* Undefined instruction	*/
735	b	thread_svc_handler	/* System call			*/
736	b	thread_pabort_handler	/* Prefetch abort		*/
737	b	thread_dabort_handler	/* Data abort			*/
738	b	.			/* Reserved			*/
739	b	thread_irq_handler	/* IRQ				*/
740	b	thread_fiq_handler	/* FIQ				*/
741
742thread_und_handler:
743	cpsid	aif
744	maybe_restore_mapping
745	strd	r0, r1, [sp, #THREAD_CORE_LOCAL_R0]
746	mrs	r1, spsr
747	tst	r1, #CPSR_T
748	subne	lr, lr, #2
749	subeq	lr, lr, #4
750	mov	r0, #ABORT_TYPE_UNDEF
751	b	thread_abort_common
752
753thread_dabort_handler:
754	cpsid	aif
755	maybe_restore_mapping
756	strd	r0, r1, [sp, #THREAD_CORE_LOCAL_R0]
757	sub	lr, lr, #8
758	mov	r0, #ABORT_TYPE_DATA
759	b	thread_abort_common
760
761thread_pabort_handler:
762	cpsid	aif
763	maybe_restore_mapping
764	strd	r0, r1, [sp, #THREAD_CORE_LOCAL_R0]
765	sub	lr, lr, #4
766	mov	r0, #ABORT_TYPE_PREFETCH
767
768thread_abort_common:
769	/*
770	 * At this label:
771	 * cpsr is in mode undef or abort
772	 * sp is still pointing to struct thread_core_local belonging to
773	 * this core.
774	 * {r0, r1} are saved in struct thread_core_local pointed to by sp
775	 * {r2-r11, ip} are untouched.
776	 * r0 holds the first argument for abort_handler()
777	 */
778
779	/*
780	 * Update core local flags.
781	 * flags = (flags << THREAD_CLF_SAVED_SHIFT) | THREAD_CLF_ABORT;
782	 */
783	ldr	r1, [sp, #THREAD_CORE_LOCAL_FLAGS]
784	lsl	r1, r1, #THREAD_CLF_SAVED_SHIFT
785	orr	r1, r1, #THREAD_CLF_ABORT
786
787	/*
788	 * Select stack and update flags accordingly
789	 *
790	 * Normal case:
791	 * If the abort stack is unused select that.
792	 *
793	 * Fatal error handling:
794	 * If we're already using the abort stack as noted by bit
795	 * (THREAD_CLF_SAVED_SHIFT + THREAD_CLF_ABORT_SHIFT) in the flags
796	 * field we're selecting the temporary stack instead to be able to
797	 * make a stack trace of the abort in abort mode.
798	 *
799	 * r1 is initialized as a temporary stack pointer until we've
800	 * switched to system mode.
801	 */
802	tst	r1, #(THREAD_CLF_ABORT << THREAD_CLF_SAVED_SHIFT)
803	orrne	r1, r1, #THREAD_CLF_TMP /* flags |= THREAD_CLF_TMP; */
804	str	r1, [sp, #THREAD_CORE_LOCAL_FLAGS]
805	ldrne	r1, [sp, #THREAD_CORE_LOCAL_TMP_STACK_VA_END]
806	ldreq	r1, [sp, #THREAD_CORE_LOCAL_ABT_STACK_VA_END]
807
808	/*
809	 * Store registers on stack fitting struct thread_abort_regs
810	 * start from the end of the struct
811	 * {r2-r11, ip}
812	 * Load content of previously saved {r0-r1} and stores
813	 * it up to the pad field.
814	 * After this is only {usr_sp, usr_lr} missing in the struct
815	 */
816	stmdb	r1!, {r2-r11, ip}	/* Push on the selected stack */
817	ldrd	r2, r3, [sp, #THREAD_CORE_LOCAL_R0]
818	/* Push the original {r0-r1} on the selected stack */
819	stmdb	r1!, {r2-r3}
820	mrs	r3, spsr
821	/* Push {pad, spsr, elr} on the selected stack */
822	stmdb	r1!, {r2, r3, lr}
823
824	cps	#CPSR_MODE_SYS
825	str	lr, [r1, #-4]!
826	str	sp, [r1, #-4]!
827	mov	sp, r1
828
829	bl	abort_handler
830
831	mov	ip, sp
832	ldr	sp, [ip], #4
833	ldr	lr, [ip], #4
834
835	/*
836	 * Even if we entered via CPSR_MODE_UND, we are returning via
837	 * CPSR_MODE_ABT. It doesn't matter as lr and spsr are assigned
838	 * here.
839	 */
840	cps	#CPSR_MODE_ABT
841	ldm	ip!, {r0, r1, lr}	/* r0 is pad */
842	msr	spsr_fsxc, r1
843
844	/* Update core local flags */
845	ldr	r0, [sp, #THREAD_CORE_LOCAL_FLAGS]
846	lsr	r0, r0, #THREAD_CLF_SAVED_SHIFT
847	str	r0, [sp, #THREAD_CORE_LOCAL_FLAGS]
848
849	cmp_spsr_user_mode r1
850	ldm	ip, {r0-r11, ip}
851	movnes	pc, lr
852	b	eret_to_user_mode
853	/* end thread_abort_common */
854
855thread_svc_handler:
856	cpsid	aif
857
858	maybe_restore_mapping
859
860	push	{r0-r7, lr}
861	mrs	r0, spsr
862	push	{r0}
863	mov	r0, sp
864	bl	tee_svc_handler
865	cpsid	aif	/* In case something was unmasked */
866	pop	{r0}
867	msr	spsr_fsxc, r0
868	cmp_spsr_user_mode r0
869	pop	{r0-r7, lr}
870	movnes	pc, lr
871	b	eret_to_user_mode
872	/* end thread_svc_handler */
873
874thread_fiq_handler:
875#if defined(CFG_ARM_GICV3)
876	foreign_intr_handler	fiq
877#else
878	native_intr_handler	fiq
879#endif
880	/* end thread_fiq_handler */
881
882thread_irq_handler:
883#if defined(CFG_ARM_GICV3)
884	native_intr_handler	irq
885#else
886	foreign_intr_handler	irq
887#endif
888	/* end thread_irq_handler */
889
890	/*
891	 * Returns to user mode.
892	 * Expects to be jumped to with lr pointing to the user space
893	 * address to jump to and spsr holding the desired cpsr. Async
894	 * abort, irq and fiq should be masked.
895	 */
896eret_to_user_mode:
897	write_tpidrprw r0
898#if defined(CFG_CORE_UNMAP_CORE_AT_EL0) || defined(CFG_WITH_LPAE)
899	write_tpidruro r1
900#endif
901
902#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
903	ldr	r0, =thread_user_kcode_offset
904	ldr	r0, [r0]
905	adr	r1, thread_vect_table
906	sub	r1, r1, r0
907	write_vbar r1
908	isb
909
910	/* Jump into the reduced mapping before the full mapping is removed */
911	ldr	r1, =1f
912	sub	r1, r1, r0
913	bx	r1
9141:
915#endif /*CFG_CORE_UNMAP_CORE_AT_EL0*/
916
917#ifdef CFG_WITH_LPAE
918	read_ttbr0_64bit r0, r1
919#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
920	add	r0, r0, #CORE_MMU_L1_TBL_OFFSET
921#endif
922	/* switch to user ASID */
923	orr	r1, r1, #BIT(TTBR_ASID_SHIFT - 32)
924	write_ttbr0_64bit r0, r1
925	isb
926#else /*!CFG_WITH_LPAE*/
927#ifdef CFG_CORE_UNMAP_CORE_AT_EL0
928	read_ttbr1 r0
929	add	r0, r0, #CORE_MMU_L1_TBL_OFFSET
930	write_ttbr1 r0
931	isb
932#endif
933	read_contextidr r0
934	orr	r0, r0, #BIT(0)
935	write_contextidr r0
936	isb
937#endif /*!CFG_WITH_LPAE*/
938
939	read_tpidrprw r0
940#if defined(CFG_CORE_UNMAP_CORE_AT_EL0) || defined(CFG_WITH_LPAE)
941	read_tpidruro r1
942#endif
943
944	movs	pc, lr
945UNWIND(	.fnend)
946END_FUNC thread_vect_table
947