1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * linux/arch/arm/kernel/entry-armv.S
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)
9 * Low-level vector interface routines
11 * Note: there is a StrongARM bug in the STMIA rn, {regs}^ instruction
12 * that causes it to save wrong values... Be aware!
15 #include <linux/init.h>
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 #ifndef CONFIG_GENERIC_IRQ_MULTI_HANDLER
23 #include <mach/entry-macro.S>
25 #include <asm/thread_notify.h>
26 #include <asm/unwind.h>
27 #include <asm/unistd.h>
29 #include <asm/system_info.h>
30 #include <asm/uaccess-asm.h>
32 #include "entry-header.S"
33 #include <asm/entry-macro-multi.S>
34 #include <asm/probes.h>
40 #ifdef CONFIG_GENERIC_IRQ_MULTI_HANDLER
42 bl generic_handle_arch_irq
44 arch_irq_handler_default
49 @ PABORT handler takes pt_regs in r2, fault address in r4 and psr in r5
53 ldr pc, [ip, #PROCESSOR_PABT_FUNC]
62 @ Call the processor-specific abort handler:
65 @ r4 - aborted context pc
66 @ r5 - aborted context psr
68 @ The abort handler must return the aborted address in r0, and
69 @ the fault status register in r1. r9 must be preserved.
74 ldr pc, [ip, #PROCESSOR_DABT_FUNC]
80 .section .entry.text,"ax",%progbits
83 * Invalid mode handlers
85 .macro inv_entry, reason
86 sub sp, sp, #PT_REGS_SIZE
87 ARM( stmib sp, {r1 - lr} )
88 THUMB( stmia sp, {r0 - r12} )
89 THUMB( str sp, [sp, #S_SP] )
90 THUMB( str lr, [sp, #S_LR] )
95 inv_entry BAD_PREFETCH
97 ENDPROC(__pabt_invalid)
102 ENDPROC(__dabt_invalid)
107 ENDPROC(__irq_invalid)
110 inv_entry BAD_UNDEFINSTR
113 @ XXX fall through to common_invalid
117 @ common_invalid - generic code for failed exception (re-entrant version of handlers)
123 add r0, sp, #S_PC @ here for interlock avoidance
124 mov r7, #-1 @ "" "" "" ""
125 str r4, [sp] @ save preserved r0
126 stmia r0, {r5 - r7} @ lr_<exception>,
127 @ cpsr_<exception>, "old_r0"
131 ENDPROC(__und_invalid)
137 #if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5)
138 #define SPFIX(code...) code
140 #define SPFIX(code...)
143 .macro svc_entry, stack_hole=0, trace=1, uaccess=1
145 UNWIND(.save {r0 - pc} )
146 sub sp, sp, #(SVC_REGS_SIZE + \stack_hole - 4)
147 #ifdef CONFIG_THUMB2_KERNEL
148 SPFIX( str r0, [sp] ) @ temporarily saved
150 SPFIX( tst r0, #4 ) @ test original stack alignment
151 SPFIX( ldr r0, [sp] ) @ restored
155 SPFIX( subeq sp, sp, #4 )
159 add r7, sp, #S_SP - 4 @ here for interlock avoidance
160 mov r6, #-1 @ "" "" "" ""
161 add r2, sp, #(SVC_REGS_SIZE + \stack_hole - 4)
162 SPFIX( addeq r2, r2, #4 )
163 str r3, [sp, #-4]! @ save the "real" r0 copied
164 @ from the exception stack
169 @ We are now ready to fill in the remaining blanks on the stack:
173 @ r4 - lr_<exception>, already fixed up for correct return/restart
174 @ r5 - spsr_<exception>
175 @ r6 - orig_r0 (see pt_regs definition in ptrace.h)
180 uaccess_entry tsk, r0, r1, r2, \uaccess
183 #ifdef CONFIG_TRACE_IRQFLAGS
184 bl trace_hardirqs_off
194 THUMB( ldr r5, [sp, #S_PSR] ) @ potentially updated CPSR
195 svc_exit r5 @ return from exception
204 #ifdef CONFIG_PREEMPTION
205 ldr r8, [tsk, #TI_PREEMPT] @ get preempt count
206 ldr r0, [tsk, #TI_FLAGS] @ get flags
207 teq r8, #0 @ if preempt count != 0
208 movne r0, #0 @ force flags to 0
209 tst r0, #_TIF_NEED_RESCHED
213 svc_exit r5, irq = 1 @ return from exception
219 #ifdef CONFIG_PREEMPTION
222 1: bl preempt_schedule_irq @ irq en/disable is done inside
223 ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS
224 tst r0, #_TIF_NEED_RESCHED
230 @ Correct the PC such that it is pointing at the instruction
231 @ which caused the fault. If the faulting instruction was ARM
232 @ the PC will be pointing at the next instruction, and have to
233 @ subtract 4. Otherwise, it is Thumb, and the PC will be
234 @ pointing at the second half of the Thumb instruction. We
235 @ have to subtract 2.
244 #ifdef CONFIG_KPROBES
245 @ If a kprobe is about to simulate a "stmdb sp..." instruction,
246 @ it obviously needs free stack space which then will belong to
248 svc_entry MAX_STACK_SIZE
253 mov r1, #4 @ PC correction to apply
254 THUMB( tst r5, #PSR_T_BIT ) @ exception taken in Thumb mode?
255 THUMB( movne r1, #2 ) @ if so, fix up PC correction
256 mov r0, sp @ struct pt_regs *regs
261 ldr r5, [sp, #S_PSR] @ Get SVC cpsr
262 svc_exit r5 @ return from exception
271 svc_exit r5 @ return from exception
278 mov r0, sp @ struct pt_regs *regs
295 * Abort mode handlers
299 @ Taking a FIQ in abort mode is similar to taking a FIQ in SVC mode
300 @ and reuses the same macros. However in abort mode we must also
301 @ save/restore lr_abt and spsr_abt to make nested aborts safe.
307 ARM( msr cpsr_c, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
308 THUMB( mov r0, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
309 THUMB( msr cpsr_c, r0 )
310 mov r1, lr @ Save lr_abt
311 mrs r2, spsr @ Save spsr_abt, abort is now safe
312 ARM( msr cpsr_c, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
313 THUMB( mov r0, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
314 THUMB( msr cpsr_c, r0 )
317 add r0, sp, #8 @ struct pt_regs *regs
321 ARM( msr cpsr_c, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
322 THUMB( mov r0, #ABT_MODE | PSR_I_BIT | PSR_F_BIT )
323 THUMB( msr cpsr_c, r0 )
324 mov lr, r1 @ Restore lr_abt, abort is unsafe
325 msr spsr_cxsf, r2 @ Restore spsr_abt
326 ARM( msr cpsr_c, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
327 THUMB( mov r0, #SVC_MODE | PSR_I_BIT | PSR_F_BIT )
328 THUMB( msr cpsr_c, r0 )
337 * EABI note: sp_svc is always 64-bit aligned here, so should PT_REGS_SIZE
340 #if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5) && (PT_REGS_SIZE & 7)
341 #error "sizeof(struct pt_regs) must be a multiple of 8"
344 .macro usr_entry, trace=1, uaccess=1
346 UNWIND(.cantunwind ) @ don't unwind the user space
347 sub sp, sp, #PT_REGS_SIZE
348 ARM( stmib sp, {r1 - r12} )
349 THUMB( stmia sp, {r0 - r12} )
351 ATRAP( mrc p15, 0, r7, c1, c0, 0)
352 ATRAP( ldr r8, .LCcralign)
355 add r0, sp, #S_PC @ here for interlock avoidance
356 mov r6, #-1 @ "" "" "" ""
358 str r3, [sp] @ save the "real" r0 copied
359 @ from the exception stack
361 ATRAP( ldr r8, [r8, #0])
364 @ We are now ready to fill in the remaining blanks on the stack:
366 @ r4 - lr_<exception>, already fixed up for correct return/restart
367 @ r5 - spsr_<exception>
368 @ r6 - orig_r0 (see pt_regs definition in ptrace.h)
370 @ Also, separately save sp_usr and lr_usr
373 ARM( stmdb r0, {sp, lr}^ )
374 THUMB( store_user_sp_lr r0, r1, S_SP - S_PC )
380 @ Enable the alignment trap while in kernel mode
382 ATRAP( mcrne p15, 0, r8, c1, c0, 0)
384 reload_current r7, r8
387 @ Clear FP to mark the first stack frame
392 #ifdef CONFIG_TRACE_IRQFLAGS
393 bl trace_hardirqs_off
395 ct_user_exit save = 0
399 .macro kuser_cmpxchg_check
400 #if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS)
402 #warning "NPTL on non MMU needs fixing"
404 @ Make sure our user space atomic helper is restarted
405 @ if it was interrupted in a critical region. Here we
406 @ perform a quick test inline since it should be false
407 @ 99.9999% of the time. The rest is done out of line.
410 blhs kuser_cmpxchg64_fixup
432 b ret_to_user_from_irq
445 @ r2 = regs->ARM_pc, which is either 2 or 4 bytes ahead of the
446 @ faulting instruction depending on Thumb mode.
447 @ r3 = regs->ARM_cpsr
449 @ The emulation code returns using r9 if it has emulated the
450 @ instruction, or the more conventional lr if we are to treat
451 @ this as a real undefined instruction
453 badr r9, ret_from_exception
455 @ IRQs must be enabled before attempting to read the instruction from
456 @ user space since that could cause a page/translation fault if the
457 @ page table was modified by another CPU.
460 tst r3, #PSR_T_BIT @ Thumb mode?
462 sub r4, r2, #4 @ ARM instr at LR - 4
464 ARM_BE8(rev r0, r0) @ little endian instruction
468 @ r0 = 32-bit ARM instruction which caused the exception
469 @ r2 = PC value for the following instruction (:= regs->ARM_pc)
470 @ r4 = PC value for the faulting instruction
471 @ lr = 32-bit undefined instruction function
472 badr lr, __und_usr_fault_32
477 sub r4, r2, #2 @ First half of thumb instr at LR - 2
478 #if CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7
480 * Thumb-2 instruction handling. Note that because pre-v6 and >= v6 platforms
481 * can never be supported in a single kernel, this code is not applicable at
482 * all when __LINUX_ARM_ARCH__ < 6. This allows simplifying assumptions to be
483 * made about .arch directives.
485 #if __LINUX_ARM_ARCH__ < 7
486 /* If the target CPU may not be Thumb-2-capable, a run-time check is needed: */
487 #define NEED_CPU_ARCHITECTURE
488 ldr r5, .LCcpu_architecture
490 cmp r5, #CPU_ARCH_ARMv7
491 blo __und_usr_fault_16 @ 16bit undefined instruction
493 * The following code won't get run unless the running CPU really is v7, so
494 * coding round the lack of ldrht on older arches is pointless. Temporarily
495 * override the assembler target arch with the minimum required instead:
500 ARM_BE8(rev16 r5, r5) @ little endian instruction
501 cmp r5, #0xe800 @ 32bit instruction if xx != 0
502 blo __und_usr_fault_16_pan @ 16bit undefined instruction
504 ARM_BE8(rev16 r0, r0) @ little endian instruction
506 add r2, r2, #2 @ r2 is PC + 2, make it PC + 4
507 str r2, [sp, #S_PC] @ it's a 2x16bit instr, update
508 orr r0, r0, r5, lsl #16
509 badr lr, __und_usr_fault_32
510 @ r0 = the two 16-bit Thumb instructions which caused the exception
511 @ r2 = PC value for the following Thumb instruction (:= regs->ARM_pc)
512 @ r4 = PC value for the first 16-bit Thumb instruction
513 @ lr = 32bit undefined instruction function
515 #if __LINUX_ARM_ARCH__ < 7
516 /* If the target arch was overridden, change it back: */
517 #ifdef CONFIG_CPU_32v6K
522 #endif /* __LINUX_ARM_ARCH__ < 7 */
523 #else /* !(CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7) */
530 * The out of line fixup for the ldrt instructions above.
532 .pushsection .text.fixup, "ax"
534 4: str r4, [sp, #S_PC] @ retry current instruction
537 .pushsection __ex_table,"a"
539 #if CONFIG_ARM_THUMB && __LINUX_ARM_ARCH__ >= 6 && CONFIG_CPU_V7
546 * Check whether the instruction is a co-processor instruction.
547 * If yes, we need to call the relevant co-processor handler.
549 * Note that we don't do a full check here for the co-processor
550 * instructions; all instructions with bit 27 set are well
551 * defined. The only instructions that should fault are the
552 * co-processor instructions. However, we have to watch out
553 * for the ARM6/ARM7 SWI bug.
555 * NEON is a special case that has to be handled here. Not all
556 * NEON instructions are co-processor instructions, so we have
557 * to make a special case of checking for them. Plus, there's
558 * five groups of them, so we have a table of mask/opcode pairs
559 * to check against, and if any match then we branch off into the
562 * Emulators may wish to make use of the following registers:
563 * r0 = instruction opcode (32-bit ARM or two 16-bit Thumb)
564 * r2 = PC value to resume execution after successful emulation
565 * r9 = normal "successful" return address
566 * r10 = this threads thread_info structure
567 * lr = unrecognised instruction return address
568 * IRQs enabled, FIQs enabled.
571 @ Fall-through from Thumb-2 __und_usr
574 get_thread_info r10 @ get current thread
575 adr r6, .LCneon_thumb_opcodes
579 get_thread_info r10 @ get current thread
581 adr r6, .LCneon_arm_opcodes
582 2: ldr r5, [r6], #4 @ mask value
583 ldr r7, [r6], #4 @ opcode bits matching in mask
584 cmp r5, #0 @ end mask?
587 cmp r8, r7 @ NEON instruction?
590 strb r7, [r10, #TI_USED_CP + 10] @ mark CP#10 as used
591 strb r7, [r10, #TI_USED_CP + 11] @ mark CP#11 as used
592 b do_vfp @ let VFP handler handle this
595 tst r0, #0x08000000 @ only CDP/CPRT/LDC/STC have bit 27
596 tstne r0, #0x04000000 @ bit 26 set on both ARM and Thumb-2
598 and r8, r0, #0x00000f00 @ mask out CP number
600 add r6, r10, r8, lsr #8 @ add used_cp[] array offset first
601 strb r7, [r6, #TI_USED_CP] @ set appropriate used_cp[]
603 @ Test if we need to give access to iWMMXt coprocessors
604 ldr r5, [r10, #TI_FLAGS]
605 rsbs r7, r8, #(1 << 8) @ CP 0 or 1 only
606 movscs r7, r5, lsr #(TIF_USING_IWMMXT + 1)
607 bcs iwmmxt_task_enable
609 ARM( add pc, pc, r8, lsr #6 )
610 THUMB( lsr r8, r8, #6 )
615 W(b) do_fpe @ CP#1 (FPE)
616 W(b) do_fpe @ CP#2 (FPE)
625 W(b) do_vfp @ CP#10 (VFP)
626 W(b) do_vfp @ CP#11 (VFP)
628 ret.w lr @ CP#10 (VFP)
629 ret.w lr @ CP#11 (VFP)
633 ret.w lr @ CP#14 (Debug)
634 ret.w lr @ CP#15 (Control)
636 #ifdef NEED_CPU_ARCHITECTURE
639 .word __cpu_architecture
646 .word 0xfe000000 @ mask
647 .word 0xf2000000 @ opcode
649 .word 0xff100000 @ mask
650 .word 0xf4000000 @ opcode
652 .word 0x00000000 @ mask
653 .word 0x00000000 @ opcode
655 .LCneon_thumb_opcodes:
656 .word 0xef000000 @ mask
657 .word 0xef000000 @ opcode
659 .word 0xff100000 @ mask
660 .word 0xf9000000 @ opcode
662 .word 0x00000000 @ mask
663 .word 0x00000000 @ opcode
668 add r10, r10, #TI_FPSTATE @ r10 = workspace
669 ldr pc, [r4] @ Call FP module USR entry point
672 * The FP module is called with these registers set:
675 * r9 = normal "successful" return address
677 * lr = unrecognised FP instruction return address
693 __und_usr_fault_16_pan:
698 badr lr, ret_from_exception
700 ENDPROC(__und_usr_fault_32)
701 ENDPROC(__und_usr_fault_16)
711 * This is the return code to user mode for abort handlers
713 ENTRY(ret_from_exception)
721 ENDPROC(ret_from_exception)
727 mov r0, sp @ struct pt_regs *regs
730 restore_user_regs fast = 0, offset = 0
735 * Register switch for ARMv3 and ARMv4 processors
736 * r0 = previous task_struct, r1 = previous thread_info, r2 = next thread_info
737 * previous and next are guaranteed not to be the same.
742 add ip, r1, #TI_CPU_SAVE
743 ARM( stmia ip!, {r4 - sl, fp, sp, lr} ) @ Store most regs on stack
744 THUMB( stmia ip!, {r4 - sl, fp} ) @ Store most regs on stack
745 THUMB( str sp, [ip], #4 )
746 THUMB( str lr, [ip], #4 )
747 ldr r4, [r2, #TI_TP_VALUE]
748 ldr r5, [r2, #TI_TP_VALUE + 4]
749 #ifdef CONFIG_CPU_USE_DOMAINS
750 mrc p15, 0, r6, c3, c0, 0 @ Get domain register
751 str r6, [r1, #TI_CPU_DOMAIN] @ Save old domain register
752 ldr r6, [r2, #TI_CPU_DOMAIN]
754 switch_tls r1, r4, r5, r3, r7
755 #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
756 ldr r7, [r2, #TI_TASK]
757 ldr r8, =__stack_chk_guard
758 .if (TSK_STACK_CANARY > IMM12_MASK)
759 add r7, r7, #TSK_STACK_CANARY & ~IMM12_MASK
761 ldr r7, [r7, #TSK_STACK_CANARY & IMM12_MASK]
762 #elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO)
763 mov r7, r2 @ Preserve 'next'
765 #ifdef CONFIG_CPU_USE_DOMAINS
766 mcr p15, 0, r6, c3, c0, 0 @ Set domain register
769 add r4, r2, #TI_CPU_SAVE
770 ldr r0, =thread_notify_head
771 mov r1, #THREAD_NOTIFY_SWITCH
772 bl atomic_notifier_call_chain
773 #if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
779 ARM( ldmia r4, {r4 - sl, fp, sp, pc} ) @ Load all regs saved previously
780 THUMB( ldmia ip!, {r4 - sl, fp} ) @ Load all regs saved previously
781 THUMB( ldr sp, [ip], #4 )
782 THUMB( ldr pc, [ip] )
791 * Each segment is 32-byte aligned and will be moved to the top of the high
792 * vector page. New segments (if ever needed) must be added in front of
793 * existing ones. This mechanism should be used only for things that are
794 * really small and justified, and not be abused freely.
796 * See Documentation/arm/kernel_user_helpers.rst for formal definitions.
801 #ifdef CONFIG_ARM_THUMB
808 .macro kuser_pad, sym, size
810 .rept 4 - (. - \sym) & 3
814 .rept (\size - (. - \sym)) / 4
819 #ifdef CONFIG_KUSER_HELPERS
821 .globl __kuser_helper_start
822 __kuser_helper_start:
825 * Due to the length of some sequences, __kuser_cmpxchg64 spans 2 regular
826 * kuser "slots", therefore 0xffff0f80 is not used as a valid entry point.
829 __kuser_cmpxchg64: @ 0xffff0f60
831 #if defined(CONFIG_CPU_32v6K)
833 stmfd sp!, {r4, r5, r6, r7}
834 ldrd r4, r5, [r0] @ load old val
835 ldrd r6, r7, [r1] @ load new val
837 1: ldrexd r0, r1, [r2] @ load current val
838 eors r3, r0, r4 @ compare with oldval (1)
839 eorseq r3, r1, r5 @ compare with oldval (2)
840 strexdeq r3, r6, r7, [r2] @ store newval if eq
841 teqeq r3, #1 @ success?
842 beq 1b @ if no then retry
844 rsbs r0, r3, #0 @ set returned val and C flag
845 ldmfd sp!, {r4, r5, r6, r7}
848 #elif !defined(CONFIG_SMP)
853 * The only thing that can break atomicity in this cmpxchg64
854 * implementation is either an IRQ or a data abort exception
855 * causing another process/thread to be scheduled in the middle of
856 * the critical sequence. The same strategy as for cmpxchg is used.
858 stmfd sp!, {r4, r5, r6, lr}
859 ldmia r0, {r4, r5} @ load old val
860 ldmia r1, {r6, lr} @ load new val
861 1: ldmia r2, {r0, r1} @ load current val
862 eors r3, r0, r4 @ compare with oldval (1)
863 eorseq r3, r1, r5 @ compare with oldval (2)
864 2: stmiaeq r2, {r6, lr} @ store newval if eq
865 rsbs r0, r3, #0 @ set return val and C flag
866 ldmfd sp!, {r4, r5, r6, pc}
869 kuser_cmpxchg64_fixup:
870 @ Called from kuser_cmpxchg_fixup.
871 @ r4 = address of interrupted insn (must be preserved).
872 @ sp = saved regs. r7 and r8 are clobbered.
873 @ 1b = first critical insn, 2b = last critical insn.
874 @ If r4 >= 1b and r4 <= 2b then saved pc_usr is set to 1b.
876 sub r7, r7, #(0xffff0fff - (0xffff0f60 + (1b - __kuser_cmpxchg64)))
878 rsbscs r8, r8, #(2b - 1b)
879 strcs r7, [sp, #S_PC]
880 #if __LINUX_ARM_ARCH__ < 6
881 bcc kuser_cmpxchg32_fixup
887 #warning "NPTL on non MMU needs fixing"
894 #error "incoherent kernel configuration"
897 kuser_pad __kuser_cmpxchg64, 64
899 __kuser_memory_barrier: @ 0xffff0fa0
903 kuser_pad __kuser_memory_barrier, 32
905 __kuser_cmpxchg: @ 0xffff0fc0
907 #if __LINUX_ARM_ARCH__ < 6
912 * The only thing that can break atomicity in this cmpxchg
913 * implementation is either an IRQ or a data abort exception
914 * causing another process/thread to be scheduled in the middle
915 * of the critical sequence. To prevent this, code is added to
916 * the IRQ and data abort exception handlers to set the pc back
917 * to the beginning of the critical section if it is found to be
918 * within that critical section (see kuser_cmpxchg_fixup).
920 1: ldr r3, [r2] @ load current val
921 subs r3, r3, r0 @ compare with oldval
922 2: streq r1, [r2] @ store newval if eq
923 rsbs r0, r3, #0 @ set return val and C flag
927 kuser_cmpxchg32_fixup:
928 @ Called from kuser_cmpxchg_check macro.
929 @ r4 = address of interrupted insn (must be preserved).
930 @ sp = saved regs. r7 and r8 are clobbered.
931 @ 1b = first critical insn, 2b = last critical insn.
932 @ If r4 >= 1b and r4 <= 2b then saved pc_usr is set to 1b.
934 sub r7, r7, #(0xffff0fff - (0xffff0fc0 + (1b - __kuser_cmpxchg)))
936 rsbscs r8, r8, #(2b - 1b)
937 strcs r7, [sp, #S_PC]
942 #warning "NPTL on non MMU needs fixing"
957 /* beware -- each __kuser slot must be 8 instructions max */
958 ALT_SMP(b __kuser_memory_barrier)
963 kuser_pad __kuser_cmpxchg, 32
965 __kuser_get_tls: @ 0xffff0fe0
966 ldr r0, [pc, #(16 - 8)] @ read TLS, set in kuser_get_tls_init
968 mrc p15, 0, r0, c13, c0, 3 @ 0xffff0fe8 hardware TLS code
969 kuser_pad __kuser_get_tls, 16
971 .word 0 @ 0xffff0ff0 software TLS value, then
972 .endr @ pad up to __kuser_helper_version
974 __kuser_helper_version: @ 0xffff0ffc
975 .word ((__kuser_helper_end - __kuser_helper_start) >> 5)
977 .globl __kuser_helper_end
987 * This code is copied to 0xffff1000 so we can use branches in the
988 * vectors, rather than ldr's. Note that this code must not exceed
991 * Common stub entry macro:
992 * Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
994 * SP points to a minimal amount of processor-private memory, the address
995 * of which is copied into r0 for the mode specific abort handler.
997 .macro vector_stub, name, mode, correction=0
1002 sub lr, lr, #\correction
1006 @ Save r0, lr_<exception> (parent PC) and spsr_<exception>
1009 stmia sp, {r0, lr} @ save r0, lr
1011 str lr, [sp, #8] @ save spsr
1014 @ Prepare for SVC32 mode. IRQs remain disabled.
1017 eor r0, r0, #(\mode ^ SVC_MODE | PSR_ISETSTATE)
1021 @ the branch table must immediately follow this code
1025 THUMB( ldr lr, [r0, lr, lsl #2] )
1027 ARM( ldr lr, [pc, lr, lsl #2] )
1028 movs pc, lr @ branch to handler in SVC mode
1029 ENDPROC(vector_\name)
1032 @ handler addresses follow this label
1036 .section .stubs, "ax", %progbits
1037 @ This must be the first word
1041 ARM( swi SYS_ERROR0 )
1047 * Interrupt dispatcher
1049 vector_stub irq, IRQ_MODE, 4
1051 .long __irq_usr @ 0 (USR_26 / USR_32)
1052 .long __irq_invalid @ 1 (FIQ_26 / FIQ_32)
1053 .long __irq_invalid @ 2 (IRQ_26 / IRQ_32)
1054 .long __irq_svc @ 3 (SVC_26 / SVC_32)
1055 .long __irq_invalid @ 4
1056 .long __irq_invalid @ 5
1057 .long __irq_invalid @ 6
1058 .long __irq_invalid @ 7
1059 .long __irq_invalid @ 8
1060 .long __irq_invalid @ 9
1061 .long __irq_invalid @ a
1062 .long __irq_invalid @ b
1063 .long __irq_invalid @ c
1064 .long __irq_invalid @ d
1065 .long __irq_invalid @ e
1066 .long __irq_invalid @ f
1069 * Data abort dispatcher
1070 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
1072 vector_stub dabt, ABT_MODE, 8
1074 .long __dabt_usr @ 0 (USR_26 / USR_32)
1075 .long __dabt_invalid @ 1 (FIQ_26 / FIQ_32)
1076 .long __dabt_invalid @ 2 (IRQ_26 / IRQ_32)
1077 .long __dabt_svc @ 3 (SVC_26 / SVC_32)
1078 .long __dabt_invalid @ 4
1079 .long __dabt_invalid @ 5
1080 .long __dabt_invalid @ 6
1081 .long __dabt_invalid @ 7
1082 .long __dabt_invalid @ 8
1083 .long __dabt_invalid @ 9
1084 .long __dabt_invalid @ a
1085 .long __dabt_invalid @ b
1086 .long __dabt_invalid @ c
1087 .long __dabt_invalid @ d
1088 .long __dabt_invalid @ e
1089 .long __dabt_invalid @ f
1092 * Prefetch abort dispatcher
1093 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
1095 vector_stub pabt, ABT_MODE, 4
1097 .long __pabt_usr @ 0 (USR_26 / USR_32)
1098 .long __pabt_invalid @ 1 (FIQ_26 / FIQ_32)
1099 .long __pabt_invalid @ 2 (IRQ_26 / IRQ_32)
1100 .long __pabt_svc @ 3 (SVC_26 / SVC_32)
1101 .long __pabt_invalid @ 4
1102 .long __pabt_invalid @ 5
1103 .long __pabt_invalid @ 6
1104 .long __pabt_invalid @ 7
1105 .long __pabt_invalid @ 8
1106 .long __pabt_invalid @ 9
1107 .long __pabt_invalid @ a
1108 .long __pabt_invalid @ b
1109 .long __pabt_invalid @ c
1110 .long __pabt_invalid @ d
1111 .long __pabt_invalid @ e
1112 .long __pabt_invalid @ f
1115 * Undef instr entry dispatcher
1116 * Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
1118 vector_stub und, UND_MODE
1120 .long __und_usr @ 0 (USR_26 / USR_32)
1121 .long __und_invalid @ 1 (FIQ_26 / FIQ_32)
1122 .long __und_invalid @ 2 (IRQ_26 / IRQ_32)
1123 .long __und_svc @ 3 (SVC_26 / SVC_32)
1124 .long __und_invalid @ 4
1125 .long __und_invalid @ 5
1126 .long __und_invalid @ 6
1127 .long __und_invalid @ 7
1128 .long __und_invalid @ 8
1129 .long __und_invalid @ 9
1130 .long __und_invalid @ a
1131 .long __und_invalid @ b
1132 .long __und_invalid @ c
1133 .long __und_invalid @ d
1134 .long __und_invalid @ e
1135 .long __und_invalid @ f
1139 /*=============================================================================
1140 * Address exception handler
1141 *-----------------------------------------------------------------------------
1142 * These aren't too critical.
1143 * (they're not supposed to happen, and won't happen in 32-bit data mode).
1149 /*=============================================================================
1151 *-----------------------------------------------------------------------------
1152 * Handle a FIQ using the SVC stack allowing FIQ act like NMI on x86
1155 vector_stub fiq, FIQ_MODE, 4
1157 .long __fiq_usr @ 0 (USR_26 / USR_32)
1158 .long __fiq_svc @ 1 (FIQ_26 / FIQ_32)
1159 .long __fiq_svc @ 2 (IRQ_26 / IRQ_32)
1160 .long __fiq_svc @ 3 (SVC_26 / SVC_32)
1176 .section .vectors, "ax", %progbits
1180 W(ldr) pc, .L__vectors_start + 0x1000
1183 W(b) vector_addrexcptn