xref: /linux/arch/arm/kernel/entry-armv.S (revision cf5c5763eb531ff5120111ad300126e926fb5a56)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *  linux/arch/arm/kernel/entry-armv.S
4 *
5 *  Copyright (C) 1996,1997,1998 Russell King.
6 *  ARM700 fix by Matthew Godbolt (linux-user@willothewisp.demon.co.uk)
7 *  nommu support by Hyok S. Choi (hyok.choi@samsung.com)
8 *
9 *  Low-level vector interface routines
10 *
11 *  Note:  there is a StrongARM bug in the STMIA rn, {regs}^ instruction
12 *  that causes it to save wrong values...  Be aware!
13 */
14
15#include <linux/init.h>
16
17#include <asm/assembler.h>
18#include <asm/memory.h>
19#include <asm/glue-df.h>
20#include <asm/glue-pf.h>
21#include <asm/vfpmacros.h>
22#include <asm/thread_notify.h>
23#include <asm/unwind.h>
24#include <asm/unistd.h>
25#include <asm/tls.h>
26#include <asm/system_info.h>
27#include <asm/uaccess-asm.h>
28
29#include "entry-header.S"
30#include <asm/probes.h>
31
32/*
33 * Interrupt handling.
34 */
35	.macro	irq_handler, from_user:req
36	mov	r1, sp
37	ldr_this_cpu r2, irq_stack_ptr, r2, r3
38	.if	\from_user == 0
39	@
40	@ If we took the interrupt while running in the kernel, we may already
41	@ be using the IRQ stack, so revert to the original value in that case.
42	@
43	subs	r3, r2, r1		@ SP above bottom of IRQ stack?
44	rsbscs	r3, r3, #THREAD_SIZE	@ ... and below the top?
45#ifdef CONFIG_VMAP_STACK
46	ldr_va	r3, high_memory, cc	@ End of the linear region
47	cmpcc	r3, r1			@ Stack pointer was below it?
48#endif
49	bcc	0f			@ If not, switch to the IRQ stack
50	mov	r0, r1
51	bl	generic_handle_arch_irq
52	b	1f
530:
54	.endif
55
56	mov_l	r0, generic_handle_arch_irq
57	bl	call_with_stack
581:
59	.endm
60
61	.macro	pabt_helper
62	@ PABORT handler takes pt_regs in r2, fault address in r4 and psr in r5
63#ifdef MULTI_PABORT
64	ldr	ip, .LCprocfns
65	mov	lr, pc
66	ldr	pc, [ip, #PROCESSOR_PABT_FUNC]
67#else
68	bl	CPU_PABORT_HANDLER
69#endif
70	.endm
71
72	.macro	dabt_helper
73
74	@
75	@ Call the processor-specific abort handler:
76	@
77	@  r2 - pt_regs
78	@  r4 - aborted context pc
79	@  r5 - aborted context psr
80	@
81	@ The abort handler must return the aborted address in r0, and
82	@ the fault status register in r1.  r9 must be preserved.
83	@
84#ifdef MULTI_DABORT
85	ldr	ip, .LCprocfns
86	mov	lr, pc
87	ldr	pc, [ip, #PROCESSOR_DABT_FUNC]
88#else
89	bl	CPU_DABORT_HANDLER
90#endif
91	.endm
92
93	.section	.entry.text,"ax",%progbits
94
95/*
96 * Invalid mode handlers
97 */
98	.macro	inv_entry, reason
99	sub	sp, sp, #PT_REGS_SIZE
100 ARM(	stmib	sp, {r1 - lr}		)
101 THUMB(	stmia	sp, {r0 - r12}		)
102 THUMB(	str	sp, [sp, #S_SP]		)
103 THUMB(	str	lr, [sp, #S_LR]		)
104	mov	r1, #\reason
105	.endm
106
107__pabt_invalid:
108	inv_entry BAD_PREFETCH
109	b	common_invalid
110ENDPROC(__pabt_invalid)
111
112__dabt_invalid:
113	inv_entry BAD_DATA
114	b	common_invalid
115ENDPROC(__dabt_invalid)
116
117__irq_invalid:
118	inv_entry BAD_IRQ
119	b	common_invalid
120ENDPROC(__irq_invalid)
121
122__und_invalid:
123	inv_entry BAD_UNDEFINSTR
124
125	@
126	@ XXX fall through to common_invalid
127	@
128
129@
130@ common_invalid - generic code for failed exception (re-entrant version of handlers)
131@
132common_invalid:
133	zero_fp
134
135	ldmia	r0, {r4 - r6}
136	add	r0, sp, #S_PC		@ here for interlock avoidance
137	mov	r7, #-1			@  ""   ""    ""        ""
138	str	r4, [sp]		@ save preserved r0
139	stmia	r0, {r5 - r7}		@ lr_<exception>,
140					@ cpsr_<exception>, "old_r0"
141
142	mov	r0, sp
143	b	bad_mode
144ENDPROC(__und_invalid)
145
146/*
147 * SVC mode handlers
148 */
149
150#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5)
151#define SPFIX(code...) code
152#else
153#define SPFIX(code...)
154#endif
155
156	.macro	svc_entry, stack_hole=0, trace=1, uaccess=1, overflow_check=1
157 UNWIND(.fnstart		)
158	sub	sp, sp, #(SVC_REGS_SIZE + \stack_hole)
159 THUMB(	add	sp, r1		)	@ get SP in a GPR without
160 THUMB(	sub	r1, sp, r1	)	@ using a temp register
161
162	.if	\overflow_check
163 UNWIND(.save	{r0 - pc}	)
164	do_overflow_check (SVC_REGS_SIZE + \stack_hole)
165	.endif
166
167#ifdef CONFIG_THUMB2_KERNEL
168	tst	r1, #4			@ test stack pointer alignment
169	sub	r1, sp, r1		@ restore original R1
170	sub	sp, r1			@ restore original SP
171#else
172 SPFIX(	tst	sp, #4		)
173#endif
174 SPFIX(	subne	sp, sp, #4	)
175
176 ARM(	stmib	sp, {r1 - r12}	)
177 THUMB(	stmia	sp, {r0 - r12}	)	@ No STMIB in Thumb-2
178
179	ldmia	r0, {r3 - r5}
180	add	r7, sp, #S_SP		@ here for interlock avoidance
181	mov	r6, #-1			@  ""  ""      ""       ""
182	add	r2, sp, #(SVC_REGS_SIZE + \stack_hole)
183 SPFIX(	addne	r2, r2, #4	)
184	str	r3, [sp]		@ save the "real" r0 copied
185					@ from the exception stack
186
187	mov	r3, lr
188
189	@
190	@ We are now ready to fill in the remaining blanks on the stack:
191	@
192	@  r2 - sp_svc
193	@  r3 - lr_svc
194	@  r4 - lr_<exception>, already fixed up for correct return/restart
195	@  r5 - spsr_<exception>
196	@  r6 - orig_r0 (see pt_regs definition in ptrace.h)
197	@
198	stmia	r7, {r2 - r6}
199
200	get_thread_info tsk
201	uaccess_entry tsk, r0, r1, r2, \uaccess
202
203	.if \trace
204#ifdef CONFIG_TRACE_IRQFLAGS
205	bl	trace_hardirqs_off
206#endif
207	.endif
208	.endm
209
210	.align	5
211__dabt_svc:
212	svc_entry uaccess=0
213	mov	r2, sp
214	dabt_helper
215 THUMB(	ldr	r5, [sp, #S_PSR]	)	@ potentially updated CPSR
216	svc_exit r5				@ return from exception
217 UNWIND(.fnend		)
218ENDPROC(__dabt_svc)
219
220	.align	5
221__irq_svc:
222	svc_entry
223	irq_handler from_user=0
224
225#ifdef CONFIG_PREEMPTION
226	ldr	r8, [tsk, #TI_PREEMPT]		@ get preempt count
227	ldr	r0, [tsk, #TI_FLAGS]		@ get flags
228	teq	r8, #0				@ if preempt count != 0
229	movne	r0, #0				@ force flags to 0
230	tst	r0, #_TIF_NEED_RESCHED
231	blne	svc_preempt
232#endif
233
234	svc_exit r5, irq = 1			@ return from exception
235 UNWIND(.fnend		)
236ENDPROC(__irq_svc)
237
238	.ltorg
239
240#ifdef CONFIG_PREEMPTION
241svc_preempt:
242	mov	r8, lr
2431:	bl	preempt_schedule_irq		@ irq en/disable is done inside
244	ldr	r0, [tsk, #TI_FLAGS]		@ get new tasks TI_FLAGS
245	tst	r0, #_TIF_NEED_RESCHED
246	reteq	r8				@ go again
247	b	1b
248#endif
249
250__und_fault:
251	@ Correct the PC such that it is pointing at the instruction
252	@ which caused the fault.  If the faulting instruction was ARM
253	@ the PC will be pointing at the next instruction, and have to
254	@ subtract 4.  Otherwise, it is Thumb, and the PC will be
255	@ pointing at the second half of the Thumb instruction.  We
256	@ have to subtract 2.
257	ldr	r2, [r0, #S_PC]
258	sub	r2, r2, r1
259	str	r2, [r0, #S_PC]
260	b	do_undefinstr
261ENDPROC(__und_fault)
262
263	.align	5
264__und_svc:
265#ifdef CONFIG_KPROBES
266	@ If a kprobe is about to simulate a "stmdb sp..." instruction,
267	@ it obviously needs free stack space which then will belong to
268	@ the saved context.
269	svc_entry MAX_STACK_SIZE
270#else
271	svc_entry
272#endif
273
274	mov	r1, #4				@ PC correction to apply
275 THUMB(	tst	r5, #PSR_T_BIT		)	@ exception taken in Thumb mode?
276 THUMB(	movne	r1, #2			)	@ if so, fix up PC correction
277	mov	r0, sp				@ struct pt_regs *regs
278	bl	__und_fault
279
280__und_svc_finish:
281	get_thread_info tsk
282	ldr	r5, [sp, #S_PSR]		@ Get SVC cpsr
283	svc_exit r5				@ return from exception
284 UNWIND(.fnend		)
285ENDPROC(__und_svc)
286
287	.align	5
288__pabt_svc:
289	svc_entry
290	mov	r2, sp				@ regs
291	pabt_helper
292	svc_exit r5				@ return from exception
293 UNWIND(.fnend		)
294ENDPROC(__pabt_svc)
295
296	.align	5
297__fiq_svc:
298	svc_entry trace=0
299	mov	r0, sp				@ struct pt_regs *regs
300	bl	handle_fiq_as_nmi
301	svc_exit_via_fiq
302 UNWIND(.fnend		)
303ENDPROC(__fiq_svc)
304
305	.align	5
306.LCcralign:
307	.word	cr_alignment
308#ifdef MULTI_DABORT
309.LCprocfns:
310	.word	processor
311#endif
312.LCfp:
313	.word	fp_enter
314
315/*
316 * Abort mode handlers
317 */
318
319@
320@ Taking a FIQ in abort mode is similar to taking a FIQ in SVC mode
321@ and reuses the same macros. However in abort mode we must also
322@ save/restore lr_abt and spsr_abt to make nested aborts safe.
323@
324	.align 5
325__fiq_abt:
326	svc_entry trace=0
327
328 ARM(	msr	cpsr_c, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
329 THUMB( mov	r0, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
330 THUMB( msr	cpsr_c, r0 )
331	mov	r1, lr		@ Save lr_abt
332	mrs	r2, spsr	@ Save spsr_abt, abort is now safe
333 ARM(	msr	cpsr_c, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
334 THUMB( mov	r0, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
335 THUMB( msr	cpsr_c, r0 )
336	stmfd	sp!, {r1 - r2}
337
338	add	r0, sp, #8			@ struct pt_regs *regs
339	bl	handle_fiq_as_nmi
340
341	ldmfd	sp!, {r1 - r2}
342 ARM(	msr	cpsr_c, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
343 THUMB( mov	r0, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
344 THUMB( msr	cpsr_c, r0 )
345	mov	lr, r1		@ Restore lr_abt, abort is unsafe
346	msr	spsr_cxsf, r2	@ Restore spsr_abt
347 ARM(	msr	cpsr_c, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
348 THUMB( mov	r0, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
349 THUMB( msr	cpsr_c, r0 )
350
351	svc_exit_via_fiq
352 UNWIND(.fnend		)
353ENDPROC(__fiq_abt)
354
355/*
356 * User mode handlers
357 *
358 * EABI note: sp_svc is always 64-bit aligned here, so should PT_REGS_SIZE
359 */
360
361#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5) && (PT_REGS_SIZE & 7)
362#error "sizeof(struct pt_regs) must be a multiple of 8"
363#endif
364
365	.macro	usr_entry, trace=1, uaccess=1
366 UNWIND(.fnstart	)
367 UNWIND(.cantunwind	)	@ don't unwind the user space
368	sub	sp, sp, #PT_REGS_SIZE
369 ARM(	stmib	sp, {r1 - r12}	)
370 THUMB(	stmia	sp, {r0 - r12}	)
371
372 ATRAP(	mrc	p15, 0, r7, c1, c0, 0)
373 ATRAP(	ldr	r8, .LCcralign)
374
375	ldmia	r0, {r3 - r5}
376	add	r0, sp, #S_PC		@ here for interlock avoidance
377	mov	r6, #-1			@  ""  ""     ""        ""
378
379	str	r3, [sp]		@ save the "real" r0 copied
380					@ from the exception stack
381
382 ATRAP(	ldr	r8, [r8, #0])
383
384	@
385	@ We are now ready to fill in the remaining blanks on the stack:
386	@
387	@  r4 - lr_<exception>, already fixed up for correct return/restart
388	@  r5 - spsr_<exception>
389	@  r6 - orig_r0 (see pt_regs definition in ptrace.h)
390	@
391	@ Also, separately save sp_usr and lr_usr
392	@
393	stmia	r0, {r4 - r6}
394 ARM(	stmdb	r0, {sp, lr}^			)
395 THUMB(	store_user_sp_lr r0, r1, S_SP - S_PC	)
396
397	.if \uaccess
398	uaccess_disable ip
399	.endif
400
401	@ Enable the alignment trap while in kernel mode
402 ATRAP(	teq	r8, r7)
403 ATRAP( mcrne	p15, 0, r8, c1, c0, 0)
404
405	reload_current r7, r8
406
407	@
408	@ Clear FP to mark the first stack frame
409	@
410	zero_fp
411
412	.if	\trace
413#ifdef CONFIG_TRACE_IRQFLAGS
414	bl	trace_hardirqs_off
415#endif
416	ct_user_exit save = 0
417	.endif
418	.endm
419
420	.macro	kuser_cmpxchg_check
421#if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS)
422#ifndef CONFIG_MMU
423#warning "NPTL on non MMU needs fixing"
424#else
425	@ Make sure our user space atomic helper is restarted
426	@ if it was interrupted in a critical region.  Here we
427	@ perform a quick test inline since it should be false
428	@ 99.9999% of the time.  The rest is done out of line.
429	ldr	r0, =TASK_SIZE
430	cmp	r4, r0
431	blhs	kuser_cmpxchg64_fixup
432#endif
433#endif
434	.endm
435
436	.align	5
437__dabt_usr:
438	usr_entry uaccess=0
439	kuser_cmpxchg_check
440	mov	r2, sp
441	dabt_helper
442	b	ret_from_exception
443 UNWIND(.fnend		)
444ENDPROC(__dabt_usr)
445
446	.align	5
447__irq_usr:
448	usr_entry
449	kuser_cmpxchg_check
450	irq_handler from_user=1
451	get_thread_info tsk
452	mov	why, #0
453	b	ret_to_user_from_irq
454 UNWIND(.fnend		)
455ENDPROC(__irq_usr)
456
457	.ltorg
458
459	.align	5
460__und_usr:
461	usr_entry uaccess=0
462
463	mov	r2, r4
464	mov	r3, r5
465
466	@ r2 = regs->ARM_pc, which is either 2 or 4 bytes ahead of the
467	@      faulting instruction depending on Thumb mode.
468	@ r3 = regs->ARM_cpsr
469	@
470	@ The emulation code returns using r9 if it has emulated the
471	@ instruction, or the more conventional lr if we are to treat
472	@ this as a real undefined instruction
473	@
474	badr	r9, ret_from_exception
475
476	@ IRQs must be enabled before attempting to read the instruction from
477	@ user space since that could cause a page/translation fault if the
478	@ page table was modified by another CPU.
479	enable_irq
480
481	tst	r3, #PSR_T_BIT			@ Thumb mode?
482	bne	__und_usr_thumb
483	sub	r4, r2, #4			@ ARM instr at LR - 4
4841:	ldrt	r0, [r4]
485 ARM_BE8(rev	r0, r0)				@ little endian instruction
486
487	uaccess_disable ip
488
489	@ r0 = 32-bit ARM instruction which caused the exception
490	@ r2 = PC value for the following instruction (:= regs->ARM_pc)
491	@ r4 = PC value for the faulting instruction
492	@ lr = 32-bit undefined instruction function
493	badr	lr, __und_usr_fault_32
494	b	call_fpe
495
496__und_usr_thumb:
497	@ Thumb instruction
498	sub	r4, r2, #2			@ First half of thumb instr at LR - 2
499#if CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7
500/*
501 * Thumb-2 instruction handling.  Note that because pre-v6 and >= v6 platforms
502 * can never be supported in a single kernel, this code is not applicable at
503 * all when __LINUX_ARM_ARCH__ < 6.  This allows simplifying assumptions to be
504 * made about .arch directives.
505 */
506#if __LINUX_ARM_ARCH__ < 7
507/* If the target CPU may not be Thumb-2-capable, a run-time check is needed: */
508#define NEED_CPU_ARCHITECTURE
509	ldr	r5, .LCcpu_architecture
510	ldr	r5, [r5]
511	cmp	r5, #CPU_ARCH_ARMv7
512	blo	__und_usr_fault_16		@ 16bit undefined instruction
513/*
514 * The following code won't get run unless the running CPU really is v7, so
515 * coding round the lack of ldrht on older arches is pointless.  Temporarily
516 * override the assembler target arch with the minimum required instead:
517 */
518	.arch	armv6t2
519#endif
5202:	ldrht	r5, [r4]
521ARM_BE8(rev16	r5, r5)				@ little endian instruction
522	cmp	r5, #0xe800			@ 32bit instruction if xx != 0
523	blo	__und_usr_fault_16_pan		@ 16bit undefined instruction
5243:	ldrht	r0, [r2]
525ARM_BE8(rev16	r0, r0)				@ little endian instruction
526	uaccess_disable ip
527	add	r2, r2, #2			@ r2 is PC + 2, make it PC + 4
528	str	r2, [sp, #S_PC]			@ it's a 2x16bit instr, update
529	orr	r0, r0, r5, lsl #16
530	badr	lr, __und_usr_fault_32
531	@ r0 = the two 16-bit Thumb instructions which caused the exception
532	@ r2 = PC value for the following Thumb instruction (:= regs->ARM_pc)
533	@ r4 = PC value for the first 16-bit Thumb instruction
534	@ lr = 32bit undefined instruction function
535
536#if __LINUX_ARM_ARCH__ < 7
537/* If the target arch was overridden, change it back: */
538#ifdef CONFIG_CPU_32v6K
539	.arch	armv6k
540#else
541	.arch	armv6
542#endif
543#endif /* __LINUX_ARM_ARCH__ < 7 */
544#else /* !(CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7) */
545	b	__und_usr_fault_16
546#endif
547 UNWIND(.fnend)
548ENDPROC(__und_usr)
549
550/*
551 * The out of line fixup for the ldrt instructions above.
552 */
553	.pushsection .text.fixup, "ax"
554	.align	2
5554:	str     r4, [sp, #S_PC]			@ retry current instruction
556	ret	r9
557	.popsection
558	.pushsection __ex_table,"a"
559	.long	1b, 4b
560#if CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7
561	.long	2b, 4b
562	.long	3b, 4b
563#endif
564	.popsection
565
566/*
567 * Check whether the instruction is a co-processor instruction.
568 * If yes, we need to call the relevant co-processor handler.
569 *
570 * Note that we don't do a full check here for the co-processor
571 * instructions; all instructions with bit 27 set are well
572 * defined.  The only instructions that should fault are the
573 * co-processor instructions.  However, we have to watch out
574 * for the ARM6/ARM7 SWI bug.
575 *
576 * NEON is a special case that has to be handled here. Not all
577 * NEON instructions are co-processor instructions, so we have
578 * to make a special case of checking for them. Plus, there's
579 * five groups of them, so we have a table of mask/opcode pairs
580 * to check against, and if any match then we branch off into the
581 * NEON handler code.
582 *
583 * Emulators may wish to make use of the following registers:
584 *  r0  = instruction opcode (32-bit ARM or two 16-bit Thumb)
585 *  r2  = PC value to resume execution after successful emulation
586 *  r9  = normal "successful" return address
587 *  r10 = this threads thread_info structure
588 *  lr  = unrecognised instruction return address
589 * IRQs enabled, FIQs enabled.
590 */
591	@
592	@ Fall-through from Thumb-2 __und_usr
593	@
594#ifdef CONFIG_NEON
595	get_thread_info r10			@ get current thread
596	adr	r6, .LCneon_thumb_opcodes
597	b	2f
598#endif
599call_fpe:
600	get_thread_info r10			@ get current thread
601#ifdef CONFIG_NEON
602	adr	r6, .LCneon_arm_opcodes
6032:	ldr	r5, [r6], #4			@ mask value
604	ldr	r7, [r6], #4			@ opcode bits matching in mask
605	cmp	r5, #0				@ end mask?
606	beq	1f
607	and	r8, r0, r5
608	cmp	r8, r7				@ NEON instruction?
609	bne	2b
610	mov	r7, #1
611	strb	r7, [r10, #TI_USED_CP + 10]	@ mark CP#10 as used
612	strb	r7, [r10, #TI_USED_CP + 11]	@ mark CP#11 as used
613	b	do_vfp				@ let VFP handler handle this
6141:
615#endif
616	tst	r0, #0x08000000			@ only CDP/CPRT/LDC/STC have bit 27
617	tstne	r0, #0x04000000			@ bit 26 set on both ARM and Thumb-2
618	reteq	lr
619	and	r8, r0, #0x00000f00		@ mask out CP number
620	mov	r7, #1
621	add	r6, r10, r8, lsr #8		@ add used_cp[] array offset first
622	strb	r7, [r6, #TI_USED_CP]		@ set appropriate used_cp[]
623#ifdef CONFIG_IWMMXT
624	@ Test if we need to give access to iWMMXt coprocessors
625	ldr	r5, [r10, #TI_FLAGS]
626	rsbs	r7, r8, #(1 << 8)		@ CP 0 or 1 only
627	movscs	r7, r5, lsr #(TIF_USING_IWMMXT + 1)
628	bcs	iwmmxt_task_enable
629#endif
630 ARM(	add	pc, pc, r8, lsr #6	)
631 THUMB(	lsr	r8, r8, #6		)
632 THUMB(	add	pc, r8			)
633	nop
634
635	ret.w	lr				@ CP#0
636	W(b)	do_fpe				@ CP#1 (FPE)
637	W(b)	do_fpe				@ CP#2 (FPE)
638	ret.w	lr				@ CP#3
639	ret.w	lr				@ CP#4
640	ret.w	lr				@ CP#5
641	ret.w	lr				@ CP#6
642	ret.w	lr				@ CP#7
643	ret.w	lr				@ CP#8
644	ret.w	lr				@ CP#9
645#ifdef CONFIG_VFP
646	W(b)	do_vfp				@ CP#10 (VFP)
647	W(b)	do_vfp				@ CP#11 (VFP)
648#else
649	ret.w	lr				@ CP#10 (VFP)
650	ret.w	lr				@ CP#11 (VFP)
651#endif
652	ret.w	lr				@ CP#12
653	ret.w	lr				@ CP#13
654	ret.w	lr				@ CP#14 (Debug)
655	ret.w	lr				@ CP#15 (Control)
656
657#ifdef NEED_CPU_ARCHITECTURE
658	.align	2
659.LCcpu_architecture:
660	.word	__cpu_architecture
661#endif
662
663#ifdef CONFIG_NEON
664	.align	6
665
666.LCneon_arm_opcodes:
667	.word	0xfe000000			@ mask
668	.word	0xf2000000			@ opcode
669
670	.word	0xff100000			@ mask
671	.word	0xf4000000			@ opcode
672
673	.word	0x00000000			@ mask
674	.word	0x00000000			@ opcode
675
676.LCneon_thumb_opcodes:
677	.word	0xef000000			@ mask
678	.word	0xef000000			@ opcode
679
680	.word	0xff100000			@ mask
681	.word	0xf9000000			@ opcode
682
683	.word	0x00000000			@ mask
684	.word	0x00000000			@ opcode
685#endif
686
687do_fpe:
688	ldr	r4, .LCfp
689	add	r10, r10, #TI_FPSTATE		@ r10 = workspace
690	ldr	pc, [r4]			@ Call FP module USR entry point
691
692/*
693 * The FP module is called with these registers set:
694 *  r0  = instruction
695 *  r2  = PC+4
696 *  r9  = normal "successful" return address
697 *  r10 = FP workspace
698 *  lr  = unrecognised FP instruction return address
699 */
700
701	.pushsection .data
702	.align	2
703ENTRY(fp_enter)
704	.word	no_fp
705	.popsection
706
707ENTRY(no_fp)
708	ret	lr
709ENDPROC(no_fp)
710
711__und_usr_fault_32:
712	mov	r1, #4
713	b	1f
714__und_usr_fault_16_pan:
715	uaccess_disable ip
716__und_usr_fault_16:
717	mov	r1, #2
7181:	mov	r0, sp
719	badr	lr, ret_from_exception
720	b	__und_fault
721ENDPROC(__und_usr_fault_32)
722ENDPROC(__und_usr_fault_16)
723
724	.align	5
725__pabt_usr:
726	usr_entry
727	mov	r2, sp				@ regs
728	pabt_helper
729 UNWIND(.fnend		)
730	/* fall through */
731/*
732 * This is the return code to user mode for abort handlers
733 */
734ENTRY(ret_from_exception)
735 UNWIND(.fnstart	)
736 UNWIND(.cantunwind	)
737	get_thread_info tsk
738	mov	why, #0
739	b	ret_to_user
740 UNWIND(.fnend		)
741ENDPROC(__pabt_usr)
742ENDPROC(ret_from_exception)
743
744	.align	5
745__fiq_usr:
746	usr_entry trace=0
747	kuser_cmpxchg_check
748	mov	r0, sp				@ struct pt_regs *regs
749	bl	handle_fiq_as_nmi
750	get_thread_info tsk
751	restore_user_regs fast = 0, offset = 0
752 UNWIND(.fnend		)
753ENDPROC(__fiq_usr)
754
755/*
756 * Register switch for ARMv3 and ARMv4 processors
757 * r0 = previous task_struct, r1 = previous thread_info, r2 = next thread_info
758 * previous and next are guaranteed not to be the same.
759 */
760ENTRY(__switch_to)
761 UNWIND(.fnstart	)
762 UNWIND(.cantunwind	)
763	add	ip, r1, #TI_CPU_SAVE
764 ARM(	stmia	ip!, {r4 - sl, fp, sp, lr} )	@ Store most regs on stack
765 THUMB(	stmia	ip!, {r4 - sl, fp}	   )	@ Store most regs on stack
766 THUMB(	str	sp, [ip], #4		   )
767 THUMB(	str	lr, [ip], #4		   )
768	ldr	r4, [r2, #TI_TP_VALUE]
769	ldr	r5, [r2, #TI_TP_VALUE + 4]
770#ifdef CONFIG_CPU_USE_DOMAINS
771	mrc	p15, 0, r6, c3, c0, 0		@ Get domain register
772	str	r6, [r1, #TI_CPU_DOMAIN]	@ Save old domain register
773	ldr	r6, [r2, #TI_CPU_DOMAIN]
774#endif
775	switch_tls r1, r4, r5, r3, r7
776#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) && \
777    !defined(CONFIG_STACKPROTECTOR_PER_TASK)
778	ldr	r8, =__stack_chk_guard
779	.if (TSK_STACK_CANARY > IMM12_MASK)
780	add	r9, r2, #TSK_STACK_CANARY & ~IMM12_MASK
781	ldr	r9, [r9, #TSK_STACK_CANARY & IMM12_MASK]
782	.else
783	ldr	r9, [r2, #TSK_STACK_CANARY & IMM12_MASK]
784	.endif
785#endif
786	mov	r7, r2				@ Preserve 'next'
787#ifdef CONFIG_CPU_USE_DOMAINS
788	mcr	p15, 0, r6, c3, c0, 0		@ Set domain register
789#endif
790	mov	r5, r0
791	add	r4, r2, #TI_CPU_SAVE
792	ldr	r0, =thread_notify_head
793	mov	r1, #THREAD_NOTIFY_SWITCH
794	bl	atomic_notifier_call_chain
795#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) && \
796    !defined(CONFIG_STACKPROTECTOR_PER_TASK)
797	str	r9, [r8]
798#endif
799	mov	r0, r5
800#if !defined(CONFIG_THUMB2_KERNEL) && !defined(CONFIG_VMAP_STACK)
801	set_current r7, r8
802	ldmia	r4, {r4 - sl, fp, sp, pc}	@ Load all regs saved previously
803#else
804	mov	r1, r7
805	ldmia	r4, {r4 - sl, fp, ip, lr}	@ Load all regs saved previously
806#ifdef CONFIG_VMAP_STACK
807	@
808	@ Do a dummy read from the new stack while running from the old one so
809	@ that we can rely on do_translation_fault() to fix up any stale PMD
810	@ entries covering the vmalloc region.
811	@
812	ldr	r2, [ip]
813#endif
814
815	@ When CONFIG_THREAD_INFO_IN_TASK=n, the update of SP itself is what
816	@ effectuates the task switch, as that is what causes the observable
817	@ values of current and current_thread_info to change. When
818	@ CONFIG_THREAD_INFO_IN_TASK=y, setting current (and therefore
819	@ current_thread_info) is done explicitly, and the update of SP just
820	@ switches us to another stack, with few other side effects. In order
821	@ to prevent this distinction from causing any inconsistencies, let's
822	@ keep the 'set_current' call as close as we can to the update of SP.
823	set_current r1, r2
824	mov	sp, ip
825	ret	lr
826#endif
827 UNWIND(.fnend		)
828ENDPROC(__switch_to)
829
830#ifdef CONFIG_VMAP_STACK
831	.text
832	.align	2
833__bad_stack:
834	@
835	@ We've just detected an overflow. We need to load the address of this
836	@ CPU's overflow stack into the stack pointer register. We have only one
837	@ scratch register so let's use a sequence of ADDs including one
838	@ involving the PC, and decorate them with PC-relative group
839	@ relocations. As these are ARM only, switch to ARM mode first.
840	@
841	@ We enter here with IP clobbered and its value stashed on the mode
842	@ stack.
843	@
844THUMB(	bx	pc		)
845THUMB(	nop			)
846THUMB(	.arm			)
847	ldr_this_cpu_armv6 ip, overflow_stack_ptr
848
849	str	sp, [ip, #-4]!			@ Preserve original SP value
850	mov	sp, ip				@ Switch to overflow stack
851	pop	{ip}				@ Original SP in IP
852
853#if defined(CONFIG_UNWINDER_FRAME_POINTER) && defined(CONFIG_CC_IS_GCC)
854	mov	ip, ip				@ mov expected by unwinder
855	push	{fp, ip, lr, pc}		@ GCC flavor frame record
856#else
857	str	ip, [sp, #-8]!			@ store original SP
858	push	{fpreg, lr}			@ Clang flavor frame record
859#endif
860UNWIND( ldr	ip, [r0, #4]	)		@ load exception LR
861UNWIND( str	ip, [sp, #12]	)		@ store in the frame record
862	ldr	ip, [r0, #12]			@ reload IP
863
864	@ Store the original GPRs to the new stack.
865	svc_entry uaccess=0, overflow_check=0
866
867UNWIND( .save   {sp, pc}	)
868UNWIND( .save   {fpreg, lr}	)
869UNWIND( .setfp  fpreg, sp	)
870
871	ldr	fpreg, [sp, #S_SP]		@ Add our frame record
872						@ to the linked list
873#if defined(CONFIG_UNWINDER_FRAME_POINTER) && defined(CONFIG_CC_IS_GCC)
874	ldr	r1, [fp, #4]			@ reload SP at entry
875	add	fp, fp, #12
876#else
877	ldr	r1, [fpreg, #8]
878#endif
879	str	r1, [sp, #S_SP]			@ store in pt_regs
880
881	@ Stash the regs for handle_bad_stack
882	mov	r0, sp
883
884	@ Time to die
885	bl	handle_bad_stack
886	nop
887UNWIND( .fnend			)
888ENDPROC(__bad_stack)
889#endif
890
891	__INIT
892
893/*
894 * User helpers.
895 *
896 * Each segment is 32-byte aligned and will be moved to the top of the high
897 * vector page.  New segments (if ever needed) must be added in front of
898 * existing ones.  This mechanism should be used only for things that are
899 * really small and justified, and not be abused freely.
900 *
901 * See Documentation/arm/kernel_user_helpers.rst for formal definitions.
902 */
903 THUMB(	.arm	)
904
905	.macro	usr_ret, reg
906#ifdef CONFIG_ARM_THUMB
907	bx	\reg
908#else
909	ret	\reg
910#endif
911	.endm
912
913	.macro	kuser_pad, sym, size
914	.if	(. - \sym) & 3
915	.rept	4 - (. - \sym) & 3
916	.byte	0
917	.endr
918	.endif
919	.rept	(\size - (. - \sym)) / 4
920	.word	0xe7fddef1
921	.endr
922	.endm
923
924#ifdef CONFIG_KUSER_HELPERS
925	.align	5
926	.globl	__kuser_helper_start
927__kuser_helper_start:
928
929/*
930 * Due to the length of some sequences, __kuser_cmpxchg64 spans 2 regular
931 * kuser "slots", therefore 0xffff0f80 is not used as a valid entry point.
932 */
933
934__kuser_cmpxchg64:				@ 0xffff0f60
935
936#if defined(CONFIG_CPU_32v6K)
937
938	stmfd	sp!, {r4, r5, r6, r7}
939	ldrd	r4, r5, [r0]			@ load old val
940	ldrd	r6, r7, [r1]			@ load new val
941	smp_dmb	arm
9421:	ldrexd	r0, r1, [r2]			@ load current val
943	eors	r3, r0, r4			@ compare with oldval (1)
944	eorseq	r3, r1, r5			@ compare with oldval (2)
945	strexdeq r3, r6, r7, [r2]		@ store newval if eq
946	teqeq	r3, #1				@ success?
947	beq	1b				@ if no then retry
948	smp_dmb	arm
949	rsbs	r0, r3, #0			@ set returned val and C flag
950	ldmfd	sp!, {r4, r5, r6, r7}
951	usr_ret	lr
952
953#elif !defined(CONFIG_SMP)
954
955#ifdef CONFIG_MMU
956
957	/*
958	 * The only thing that can break atomicity in this cmpxchg64
959	 * implementation is either an IRQ or a data abort exception
960	 * causing another process/thread to be scheduled in the middle of
961	 * the critical sequence.  The same strategy as for cmpxchg is used.
962	 */
963	stmfd	sp!, {r4, r5, r6, lr}
964	ldmia	r0, {r4, r5}			@ load old val
965	ldmia	r1, {r6, lr}			@ load new val
9661:	ldmia	r2, {r0, r1}			@ load current val
967	eors	r3, r0, r4			@ compare with oldval (1)
968	eorseq	r3, r1, r5			@ compare with oldval (2)
9692:	stmiaeq	r2, {r6, lr}			@ store newval if eq
970	rsbs	r0, r3, #0			@ set return val and C flag
971	ldmfd	sp!, {r4, r5, r6, pc}
972
973	.text
974kuser_cmpxchg64_fixup:
975	@ Called from kuser_cmpxchg_fixup.
976	@ r4 = address of interrupted insn (must be preserved).
977	@ sp = saved regs. r7 and r8 are clobbered.
978	@ 1b = first critical insn, 2b = last critical insn.
979	@ If r4 >= 1b and r4 <= 2b then saved pc_usr is set to 1b.
980	mov	r7, #0xffff0fff
981	sub	r7, r7, #(0xffff0fff - (0xffff0f60 + (1b - __kuser_cmpxchg64)))
982	subs	r8, r4, r7
983	rsbscs	r8, r8, #(2b - 1b)
984	strcs	r7, [sp, #S_PC]
985#if __LINUX_ARM_ARCH__ < 6
986	bcc	kuser_cmpxchg32_fixup
987#endif
988	ret	lr
989	.previous
990
991#else
992#warning "NPTL on non MMU needs fixing"
993	mov	r0, #-1
994	adds	r0, r0, #0
995	usr_ret	lr
996#endif
997
998#else
999#error "incoherent kernel configuration"
1000#endif
1001
1002	kuser_pad __kuser_cmpxchg64, 64
1003
1004__kuser_memory_barrier:				@ 0xffff0fa0
1005	smp_dmb	arm
1006	usr_ret	lr
1007
1008	kuser_pad __kuser_memory_barrier, 32
1009
1010__kuser_cmpxchg:				@ 0xffff0fc0
1011
1012#if __LINUX_ARM_ARCH__ < 6
1013
1014#ifdef CONFIG_MMU
1015
1016	/*
1017	 * The only thing that can break atomicity in this cmpxchg
1018	 * implementation is either an IRQ or a data abort exception
1019	 * causing another process/thread to be scheduled in the middle
1020	 * of the critical sequence.  To prevent this, code is added to
1021	 * the IRQ and data abort exception handlers to set the pc back
1022	 * to the beginning of the critical section if it is found to be
1023	 * within that critical section (see kuser_cmpxchg_fixup).
1024	 */
10251:	ldr	r3, [r2]			@ load current val
1026	subs	r3, r3, r0			@ compare with oldval
10272:	streq	r1, [r2]			@ store newval if eq
1028	rsbs	r0, r3, #0			@ set return val and C flag
1029	usr_ret	lr
1030
1031	.text
1032kuser_cmpxchg32_fixup:
1033	@ Called from kuser_cmpxchg_check macro.
1034	@ r4 = address of interrupted insn (must be preserved).
1035	@ sp = saved regs. r7 and r8 are clobbered.
1036	@ 1b = first critical insn, 2b = last critical insn.
1037	@ If r4 >= 1b and r4 <= 2b then saved pc_usr is set to 1b.
1038	mov	r7, #0xffff0fff
1039	sub	r7, r7, #(0xffff0fff - (0xffff0fc0 + (1b - __kuser_cmpxchg)))
1040	subs	r8, r4, r7
1041	rsbscs	r8, r8, #(2b - 1b)
1042	strcs	r7, [sp, #S_PC]
1043	ret	lr
1044	.previous
1045
1046#else
1047#warning "NPTL on non MMU needs fixing"
1048	mov	r0, #-1
1049	adds	r0, r0, #0
1050	usr_ret	lr
1051#endif
1052
1053#else
1054
1055	smp_dmb	arm
10561:	ldrex	r3, [r2]
1057	subs	r3, r3, r0
1058	strexeq	r3, r1, [r2]
1059	teqeq	r3, #1
1060	beq	1b
1061	rsbs	r0, r3, #0
1062	/* beware -- each __kuser slot must be 8 instructions max */
1063	ALT_SMP(b	__kuser_memory_barrier)
1064	ALT_UP(usr_ret	lr)
1065
1066#endif
1067
1068	kuser_pad __kuser_cmpxchg, 32
1069
1070__kuser_get_tls:				@ 0xffff0fe0
1071	ldr	r0, [pc, #(16 - 8)]	@ read TLS, set in kuser_get_tls_init
1072	usr_ret	lr
1073	mrc	p15, 0, r0, c13, c0, 3	@ 0xffff0fe8 hardware TLS code
1074	kuser_pad __kuser_get_tls, 16
1075	.rep	3
1076	.word	0			@ 0xffff0ff0 software TLS value, then
1077	.endr				@ pad up to __kuser_helper_version
1078
1079__kuser_helper_version:				@ 0xffff0ffc
1080	.word	((__kuser_helper_end - __kuser_helper_start) >> 5)
1081
1082	.globl	__kuser_helper_end
1083__kuser_helper_end:
1084
1085#endif
1086
1087 THUMB(	.thumb	)
1088
1089/*
1090 * Vector stubs.
1091 *
1092 * This code is copied to 0xffff1000 so we can use branches in the
1093 * vectors, rather than ldr's.  Note that this code must not exceed
1094 * a page size.
1095 *
1096 * Common stub entry macro:
1097 *   Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
1098 *
1099 * SP points to a minimal amount of processor-private memory, the address
1100 * of which is copied into r0 for the mode specific abort handler.
1101 */
1102	.macro	vector_stub, name, mode, correction=0
1103	.align	5
1104
1105vector_\name:
1106	.if \correction
1107	sub	lr, lr, #\correction
1108	.endif
1109
1110	@ Save r0, lr_<exception> (parent PC)
1111	stmia	sp, {r0, lr}		@ save r0, lr
1112
1113	@ Save spsr_<exception> (parent CPSR)
11142:	mrs	lr, spsr
1115	str	lr, [sp, #8]		@ save spsr
1116
1117	@
1118	@ Prepare for SVC32 mode.  IRQs remain disabled.
1119	@
1120	mrs	r0, cpsr
1121	eor	r0, r0, #(\mode ^ SVC_MODE | PSR_ISETSTATE)
1122	msr	spsr_cxsf, r0
1123
1124	@
1125	@ the branch table must immediately follow this code
1126	@
1127	and	lr, lr, #0x0f
1128 THUMB(	adr	r0, 1f			)
1129 THUMB(	ldr	lr, [r0, lr, lsl #2]	)
1130	mov	r0, sp
1131 ARM(	ldr	lr, [pc, lr, lsl #2]	)
1132	movs	pc, lr			@ branch to handler in SVC mode
1133ENDPROC(vector_\name)
1134
1135#ifdef CONFIG_HARDEN_BRANCH_HISTORY
1136	.subsection 1
1137	.align 5
1138vector_bhb_loop8_\name:
1139	.if \correction
1140	sub	lr, lr, #\correction
1141	.endif
1142
1143	@ Save r0, lr_<exception> (parent PC)
1144	stmia	sp, {r0, lr}
1145
1146	@ bhb workaround
1147	mov	r0, #8
11483:	b	. + 4
1149	subs	r0, r0, #1
1150	bne	3b
1151	dsb
1152	isb
1153	b	2b
1154ENDPROC(vector_bhb_loop8_\name)
1155
1156vector_bhb_bpiall_\name:
1157	.if \correction
1158	sub	lr, lr, #\correction
1159	.endif
1160
1161	@ Save r0, lr_<exception> (parent PC)
1162	stmia	sp, {r0, lr}
1163
1164	@ bhb workaround
1165	mcr	p15, 0, r0, c7, c5, 6	@ BPIALL
1166	@ isb not needed due to "movs pc, lr" in the vector stub
1167	@ which gives a "context synchronisation".
1168	b	2b
1169ENDPROC(vector_bhb_bpiall_\name)
1170	.previous
1171#endif
1172
1173	.align	2
1174	@ handler addresses follow this label
11751:
1176	.endm
1177
1178	.section .stubs, "ax", %progbits
1179	@ This must be the first word
1180	.word	vector_swi
1181#ifdef CONFIG_HARDEN_BRANCH_HISTORY
1182	.word	vector_bhb_loop8_swi
1183	.word	vector_bhb_bpiall_swi
1184#endif
1185
1186vector_rst:
1187 ARM(	swi	SYS_ERROR0	)
1188 THUMB(	svc	#0		)
1189 THUMB(	nop			)
1190	b	vector_und
1191
1192/*
1193 * Interrupt dispatcher
1194 */
1195	vector_stub	irq, IRQ_MODE, 4
1196
1197	.long	__irq_usr			@  0  (USR_26 / USR_32)
1198	.long	__irq_invalid			@  1  (FIQ_26 / FIQ_32)
1199	.long	__irq_invalid			@  2  (IRQ_26 / IRQ_32)
1200	.long	__irq_svc			@  3  (SVC_26 / SVC_32)
1201	.long	__irq_invalid			@  4
1202	.long	__irq_invalid			@  5
1203	.long	__irq_invalid			@  6
1204	.long	__irq_invalid			@  7
1205	.long	__irq_invalid			@  8
1206	.long	__irq_invalid			@  9
1207	.long	__irq_invalid			@  a
1208	.long	__irq_invalid			@  b
1209	.long	__irq_invalid			@  c
1210	.long	__irq_invalid			@  d
1211	.long	__irq_invalid			@  e
1212	.long	__irq_invalid			@  f
1213
1214/*
1215 * Data abort dispatcher
1216 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
1217 */
1218	vector_stub	dabt, ABT_MODE, 8
1219
1220	.long	__dabt_usr			@  0  (USR_26 / USR_32)
1221	.long	__dabt_invalid			@  1  (FIQ_26 / FIQ_32)
1222	.long	__dabt_invalid			@  2  (IRQ_26 / IRQ_32)
1223	.long	__dabt_svc			@  3  (SVC_26 / SVC_32)
1224	.long	__dabt_invalid			@  4
1225	.long	__dabt_invalid			@  5
1226	.long	__dabt_invalid			@  6
1227	.long	__dabt_invalid			@  7
1228	.long	__dabt_invalid			@  8
1229	.long	__dabt_invalid			@  9
1230	.long	__dabt_invalid			@  a
1231	.long	__dabt_invalid			@  b
1232	.long	__dabt_invalid			@  c
1233	.long	__dabt_invalid			@  d
1234	.long	__dabt_invalid			@  e
1235	.long	__dabt_invalid			@  f
1236
1237/*
1238 * Prefetch abort dispatcher
1239 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
1240 */
1241	vector_stub	pabt, ABT_MODE, 4
1242
1243	.long	__pabt_usr			@  0 (USR_26 / USR_32)
1244	.long	__pabt_invalid			@  1 (FIQ_26 / FIQ_32)
1245	.long	__pabt_invalid			@  2 (IRQ_26 / IRQ_32)
1246	.long	__pabt_svc			@  3 (SVC_26 / SVC_32)
1247	.long	__pabt_invalid			@  4
1248	.long	__pabt_invalid			@  5
1249	.long	__pabt_invalid			@  6
1250	.long	__pabt_invalid			@  7
1251	.long	__pabt_invalid			@  8
1252	.long	__pabt_invalid			@  9
1253	.long	__pabt_invalid			@  a
1254	.long	__pabt_invalid			@  b
1255	.long	__pabt_invalid			@  c
1256	.long	__pabt_invalid			@  d
1257	.long	__pabt_invalid			@  e
1258	.long	__pabt_invalid			@  f
1259
1260/*
1261 * Undef instr entry dispatcher
1262 * Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
1263 */
1264	vector_stub	und, UND_MODE
1265
1266	.long	__und_usr			@  0 (USR_26 / USR_32)
1267	.long	__und_invalid			@  1 (FIQ_26 / FIQ_32)
1268	.long	__und_invalid			@  2 (IRQ_26 / IRQ_32)
1269	.long	__und_svc			@  3 (SVC_26 / SVC_32)
1270	.long	__und_invalid			@  4
1271	.long	__und_invalid			@  5
1272	.long	__und_invalid			@  6
1273	.long	__und_invalid			@  7
1274	.long	__und_invalid			@  8
1275	.long	__und_invalid			@  9
1276	.long	__und_invalid			@  a
1277	.long	__und_invalid			@  b
1278	.long	__und_invalid			@  c
1279	.long	__und_invalid			@  d
1280	.long	__und_invalid			@  e
1281	.long	__und_invalid			@  f
1282
1283	.align	5
1284
1285/*=============================================================================
1286 * Address exception handler
1287 *-----------------------------------------------------------------------------
1288 * These aren't too critical.
1289 * (they're not supposed to happen, and won't happen in 32-bit data mode).
1290 */
1291
1292vector_addrexcptn:
1293	b	vector_addrexcptn
1294
1295/*=============================================================================
1296 * FIQ "NMI" handler
1297 *-----------------------------------------------------------------------------
1298 * Handle a FIQ using the SVC stack allowing FIQ act like NMI on x86
1299 * systems. This must be the last vector stub, so lets place it in its own
1300 * subsection.
1301 */
1302	.subsection 2
1303	vector_stub	fiq, FIQ_MODE, 4
1304
1305	.long	__fiq_usr			@  0  (USR_26 / USR_32)
1306	.long	__fiq_svc			@  1  (FIQ_26 / FIQ_32)
1307	.long	__fiq_svc			@  2  (IRQ_26 / IRQ_32)
1308	.long	__fiq_svc			@  3  (SVC_26 / SVC_32)
1309	.long	__fiq_svc			@  4
1310	.long	__fiq_svc			@  5
1311	.long	__fiq_svc			@  6
1312	.long	__fiq_abt			@  7
1313	.long	__fiq_svc			@  8
1314	.long	__fiq_svc			@  9
1315	.long	__fiq_svc			@  a
1316	.long	__fiq_svc			@  b
1317	.long	__fiq_svc			@  c
1318	.long	__fiq_svc			@  d
1319	.long	__fiq_svc			@  e
1320	.long	__fiq_svc			@  f
1321
1322	.globl	vector_fiq
1323
1324	.section .vectors, "ax", %progbits
1325.L__vectors_start:
1326	W(b)	vector_rst
1327	W(b)	vector_und
1328	W(ldr)	pc, .L__vectors_start + 0x1000
1329	W(b)	vector_pabt
1330	W(b)	vector_dabt
1331	W(b)	vector_addrexcptn
1332	W(b)	vector_irq
1333	W(b)	vector_fiq
1334
1335#ifdef CONFIG_HARDEN_BRANCH_HISTORY
1336	.section .vectors.bhb.loop8, "ax", %progbits
1337.L__vectors_bhb_loop8_start:
1338	W(b)	vector_rst
1339	W(b)	vector_bhb_loop8_und
1340	W(ldr)	pc, .L__vectors_bhb_loop8_start + 0x1004
1341	W(b)	vector_bhb_loop8_pabt
1342	W(b)	vector_bhb_loop8_dabt
1343	W(b)	vector_addrexcptn
1344	W(b)	vector_bhb_loop8_irq
1345	W(b)	vector_bhb_loop8_fiq
1346
1347	.section .vectors.bhb.bpiall, "ax", %progbits
1348.L__vectors_bhb_bpiall_start:
1349	W(b)	vector_rst
1350	W(b)	vector_bhb_bpiall_und
1351	W(ldr)	pc, .L__vectors_bhb_bpiall_start + 0x1008
1352	W(b)	vector_bhb_bpiall_pabt
1353	W(b)	vector_bhb_bpiall_dabt
1354	W(b)	vector_addrexcptn
1355	W(b)	vector_bhb_bpiall_irq
1356	W(b)	vector_bhb_bpiall_fiq
1357#endif
1358
1359	.data
1360	.align	2
1361
1362	.globl	cr_alignment
1363cr_alignment:
1364	.space	4
1365