xref: /openbmc/linux/arch/arm/kernel/entry-armv.S (revision 791be9b976ba621b21745c30a7fca225fada9110)
11da177e4SLinus Torvalds/*
21da177e4SLinus Torvalds *  linux/arch/arm/kernel/entry-armv.S
31da177e4SLinus Torvalds *
41da177e4SLinus Torvalds *  Copyright (C) 1996,1997,1998 Russell King.
51da177e4SLinus Torvalds *  ARM700 fix by Matthew Godbolt (linux-user@willothewisp.demon.co.uk)
61da177e4SLinus Torvalds *
71da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify
81da177e4SLinus Torvalds * it under the terms of the GNU General Public License version 2 as
91da177e4SLinus Torvalds * published by the Free Software Foundation.
101da177e4SLinus Torvalds *
111da177e4SLinus Torvalds *  Low-level vector interface routines
121da177e4SLinus Torvalds *
131da177e4SLinus Torvalds *  Note:  there is a StrongARM bug in the STMIA rn, {regs}^ instruction that causes
141da177e4SLinus Torvalds *  it to save wrong values...  Be aware!
151da177e4SLinus Torvalds */
161da177e4SLinus Torvalds#include <linux/config.h>
171da177e4SLinus Torvalds
181da177e4SLinus Torvalds#include <asm/glue.h>
191da177e4SLinus Torvalds#include <asm/vfpmacros.h>
2041e46d6aSNicolas Pitre#include <asm/hardware.h>		/* should be moved into entry-macro.S */
2141e46d6aSNicolas Pitre#include <asm/arch/irqs.h>		/* should be moved into entry-macro.S */
22bce495d8SRussell King#include <asm/arch/entry-macro.S>
231da177e4SLinus Torvalds
241da177e4SLinus Torvalds#include "entry-header.S"
251da177e4SLinus Torvalds
261da177e4SLinus Torvalds/*
27187a51adSRussell King * Interrupt handling.  Preserves r7, r8, r9
28187a51adSRussell King */
29187a51adSRussell King	.macro	irq_handler
30187a51adSRussell King1:	get_irqnr_and_base r0, r6, r5, lr
31187a51adSRussell King	movne	r1, sp
32187a51adSRussell King	@
33187a51adSRussell King	@ routine called with r0 = irq number, r1 = struct pt_regs *
34187a51adSRussell King	@
35187a51adSRussell King	adrne	lr, 1b
36187a51adSRussell King	bne	asm_do_IRQ
37*791be9b9SRussell King
38*791be9b9SRussell King#ifdef CONFIG_SMP
39*791be9b9SRussell King	/*
40*791be9b9SRussell King	 * XXX
41*791be9b9SRussell King	 *
42*791be9b9SRussell King	 * this macro assumes that irqstat (r6) and base (r5) are
43*791be9b9SRussell King	 * preserved from get_irqnr_and_base above
44*791be9b9SRussell King	 */
45*791be9b9SRussell King	test_for_ipi r0, r6, r5, lr
46*791be9b9SRussell King	movne	r0, sp
47*791be9b9SRussell King	adrne	lr, 1b
48*791be9b9SRussell King	bne	do_IPI
49*791be9b9SRussell King#endif
50*791be9b9SRussell King
51187a51adSRussell King	.endm
52187a51adSRussell King
53187a51adSRussell King/*
541da177e4SLinus Torvalds * Invalid mode handlers
551da177e4SLinus Torvalds */
561da177e4SLinus Torvalds	.macro	inv_entry, sym, reason
571da177e4SLinus Torvalds	sub	sp, sp, #S_FRAME_SIZE		@ Allocate frame size in one go
581da177e4SLinus Torvalds	stmia	sp, {r0 - lr}			@ Save XXX r0 - lr
591da177e4SLinus Torvalds	ldr	r4, .LC\sym
601da177e4SLinus Torvalds	mov	r1, #\reason
611da177e4SLinus Torvalds	.endm
621da177e4SLinus Torvalds
631da177e4SLinus Torvalds__pabt_invalid:
641da177e4SLinus Torvalds	inv_entry abt, BAD_PREFETCH
651da177e4SLinus Torvalds	b	1f
661da177e4SLinus Torvalds
671da177e4SLinus Torvalds__dabt_invalid:
681da177e4SLinus Torvalds	inv_entry abt, BAD_DATA
691da177e4SLinus Torvalds	b	1f
701da177e4SLinus Torvalds
711da177e4SLinus Torvalds__irq_invalid:
721da177e4SLinus Torvalds	inv_entry irq, BAD_IRQ
731da177e4SLinus Torvalds	b	1f
741da177e4SLinus Torvalds
751da177e4SLinus Torvalds__und_invalid:
761da177e4SLinus Torvalds	inv_entry und, BAD_UNDEFINSTR
771da177e4SLinus Torvalds
781da177e4SLinus Torvalds1:	zero_fp
791da177e4SLinus Torvalds	ldmia	r4, {r5 - r7}			@ Get XXX pc, cpsr, old_r0
801da177e4SLinus Torvalds	add	r4, sp, #S_PC
811da177e4SLinus Torvalds	stmia	r4, {r5 - r7}			@ Save XXX pc, cpsr, old_r0
821da177e4SLinus Torvalds	mov	r0, sp
831da177e4SLinus Torvalds	and	r2, r6, #31			@ int mode
841da177e4SLinus Torvalds	b	bad_mode
851da177e4SLinus Torvalds
861da177e4SLinus Torvalds/*
871da177e4SLinus Torvalds * SVC mode handlers
881da177e4SLinus Torvalds */
891da177e4SLinus Torvalds	.macro	svc_entry, sym
901da177e4SLinus Torvalds	sub	sp, sp, #S_FRAME_SIZE
911da177e4SLinus Torvalds	stmia	sp, {r0 - r12}			@ save r0 - r12
921da177e4SLinus Torvalds	ldr	r2, .LC\sym
931da177e4SLinus Torvalds	add	r0, sp, #S_FRAME_SIZE
941da177e4SLinus Torvalds	ldmia	r2, {r2 - r4}			@ get pc, cpsr
951da177e4SLinus Torvalds	add	r5, sp, #S_SP
961da177e4SLinus Torvalds	mov	r1, lr
971da177e4SLinus Torvalds
981da177e4SLinus Torvalds	@
991da177e4SLinus Torvalds	@ We are now ready to fill in the remaining blanks on the stack:
1001da177e4SLinus Torvalds	@
1011da177e4SLinus Torvalds	@  r0 - sp_svc
1021da177e4SLinus Torvalds	@  r1 - lr_svc
1031da177e4SLinus Torvalds	@  r2 - lr_<exception>, already fixed up for correct return/restart
1041da177e4SLinus Torvalds	@  r3 - spsr_<exception>
1051da177e4SLinus Torvalds	@  r4 - orig_r0 (see pt_regs definition in ptrace.h)
1061da177e4SLinus Torvalds	@
1071da177e4SLinus Torvalds	stmia	r5, {r0 - r4}
1081da177e4SLinus Torvalds	.endm
1091da177e4SLinus Torvalds
1101da177e4SLinus Torvalds	.align	5
1111da177e4SLinus Torvalds__dabt_svc:
1121da177e4SLinus Torvalds	svc_entry abt
1131da177e4SLinus Torvalds
1141da177e4SLinus Torvalds	@
1151da177e4SLinus Torvalds	@ get ready to re-enable interrupts if appropriate
1161da177e4SLinus Torvalds	@
1171da177e4SLinus Torvalds	mrs	r9, cpsr
1181da177e4SLinus Torvalds	tst	r3, #PSR_I_BIT
1191da177e4SLinus Torvalds	biceq	r9, r9, #PSR_I_BIT
1201da177e4SLinus Torvalds
1211da177e4SLinus Torvalds	@
1221da177e4SLinus Torvalds	@ Call the processor-specific abort handler:
1231da177e4SLinus Torvalds	@
1241da177e4SLinus Torvalds	@  r2 - aborted context pc
1251da177e4SLinus Torvalds	@  r3 - aborted context cpsr
1261da177e4SLinus Torvalds	@
1271da177e4SLinus Torvalds	@ The abort handler must return the aborted address in r0, and
1281da177e4SLinus Torvalds	@ the fault status register in r1.  r9 must be preserved.
1291da177e4SLinus Torvalds	@
1301da177e4SLinus Torvalds#ifdef MULTI_ABORT
1311da177e4SLinus Torvalds	ldr	r4, .LCprocfns
1321da177e4SLinus Torvalds	mov	lr, pc
1331da177e4SLinus Torvalds	ldr	pc, [r4]
1341da177e4SLinus Torvalds#else
1351da177e4SLinus Torvalds	bl	CPU_ABORT_HANDLER
1361da177e4SLinus Torvalds#endif
1371da177e4SLinus Torvalds
1381da177e4SLinus Torvalds	@
1391da177e4SLinus Torvalds	@ set desired IRQ state, then call main handler
1401da177e4SLinus Torvalds	@
1411da177e4SLinus Torvalds	msr	cpsr_c, r9
1421da177e4SLinus Torvalds	mov	r2, sp
1431da177e4SLinus Torvalds	bl	do_DataAbort
1441da177e4SLinus Torvalds
1451da177e4SLinus Torvalds	@
1461da177e4SLinus Torvalds	@ IRQs off again before pulling preserved data off the stack
1471da177e4SLinus Torvalds	@
1481ec42c0cSRussell King	disable_irq
1491da177e4SLinus Torvalds
1501da177e4SLinus Torvalds	@
1511da177e4SLinus Torvalds	@ restore SPSR and restart the instruction
1521da177e4SLinus Torvalds	@
1531da177e4SLinus Torvalds	ldr	r0, [sp, #S_PSR]
1541da177e4SLinus Torvalds	msr	spsr_cxsf, r0
1551da177e4SLinus Torvalds	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
1561da177e4SLinus Torvalds
1571da177e4SLinus Torvalds	.align	5
1581da177e4SLinus Torvalds__irq_svc:
1591da177e4SLinus Torvalds	svc_entry irq
1601da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
161706fdd9fSRussell King	get_thread_info tsk
162706fdd9fSRussell King	ldr	r8, [tsk, #TI_PREEMPT]		@ get preempt count
163706fdd9fSRussell King	add	r7, r8, #1			@ increment it
164706fdd9fSRussell King	str	r7, [tsk, #TI_PREEMPT]
1651da177e4SLinus Torvalds#endif
166187a51adSRussell King	irq_handler
1671da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
168706fdd9fSRussell King	ldr	r0, [tsk, #TI_FLAGS]		@ get flags
1691da177e4SLinus Torvalds	tst	r0, #_TIF_NEED_RESCHED
1701da177e4SLinus Torvalds	blne	svc_preempt
1711da177e4SLinus Torvaldspreempt_return:
172706fdd9fSRussell King	ldr	r0, [tsk, #TI_PREEMPT]		@ read preempt value
173706fdd9fSRussell King	str	r8, [tsk, #TI_PREEMPT]		@ restore preempt count
1741da177e4SLinus Torvalds	teq	r0, r7
1751da177e4SLinus Torvalds	strne	r0, [r0, -r0]			@ bug()
1761da177e4SLinus Torvalds#endif
1771da177e4SLinus Torvalds	ldr	r0, [sp, #S_PSR]		@ irqs are already disabled
1781da177e4SLinus Torvalds	msr	spsr_cxsf, r0
1791da177e4SLinus Torvalds	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
1801da177e4SLinus Torvalds
1811da177e4SLinus Torvalds	.ltorg
1821da177e4SLinus Torvalds
1831da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
1841da177e4SLinus Torvaldssvc_preempt:
185706fdd9fSRussell King	teq	r8, #0				@ was preempt count = 0
1861da177e4SLinus Torvalds	ldreq	r6, .LCirq_stat
1871da177e4SLinus Torvalds	movne	pc, lr				@ no
1881da177e4SLinus Torvalds	ldr	r0, [r6, #4]			@ local_irq_count
1891da177e4SLinus Torvalds	ldr	r1, [r6, #8]			@ local_bh_count
1901da177e4SLinus Torvalds	adds	r0, r0, r1
1911da177e4SLinus Torvalds	movne	pc, lr
1921da177e4SLinus Torvalds	mov	r7, #0				@ preempt_schedule_irq
193706fdd9fSRussell King	str	r7, [tsk, #TI_PREEMPT]		@ expects preempt_count == 0
1941da177e4SLinus Torvalds1:	bl	preempt_schedule_irq		@ irq en/disable is done inside
195706fdd9fSRussell King	ldr	r0, [tsk, #TI_FLAGS]		@ get new tasks TI_FLAGS
1961da177e4SLinus Torvalds	tst	r0, #_TIF_NEED_RESCHED
1971da177e4SLinus Torvalds	beq	preempt_return			@ go again
1981da177e4SLinus Torvalds	b	1b
1991da177e4SLinus Torvalds#endif
2001da177e4SLinus Torvalds
2011da177e4SLinus Torvalds	.align	5
2021da177e4SLinus Torvalds__und_svc:
2031da177e4SLinus Torvalds	svc_entry und
2041da177e4SLinus Torvalds
2051da177e4SLinus Torvalds	@
2061da177e4SLinus Torvalds	@ call emulation code, which returns using r9 if it has emulated
2071da177e4SLinus Torvalds	@ the instruction, or the more conventional lr if we are to treat
2081da177e4SLinus Torvalds	@ this as a real undefined instruction
2091da177e4SLinus Torvalds	@
2101da177e4SLinus Torvalds	@  r0 - instruction
2111da177e4SLinus Torvalds	@
2121da177e4SLinus Torvalds	ldr	r0, [r2, #-4]
2131da177e4SLinus Torvalds	adr	r9, 1f
2141da177e4SLinus Torvalds	bl	call_fpe
2151da177e4SLinus Torvalds
2161da177e4SLinus Torvalds	mov	r0, sp				@ struct pt_regs *regs
2171da177e4SLinus Torvalds	bl	do_undefinstr
2181da177e4SLinus Torvalds
2191da177e4SLinus Torvalds	@
2201da177e4SLinus Torvalds	@ IRQs off again before pulling preserved data off the stack
2211da177e4SLinus Torvalds	@
2221ec42c0cSRussell King1:	disable_irq
2231da177e4SLinus Torvalds
2241da177e4SLinus Torvalds	@
2251da177e4SLinus Torvalds	@ restore SPSR and restart the instruction
2261da177e4SLinus Torvalds	@
2271da177e4SLinus Torvalds	ldr	lr, [sp, #S_PSR]		@ Get SVC cpsr
2281da177e4SLinus Torvalds	msr	spsr_cxsf, lr
2291da177e4SLinus Torvalds	ldmia	sp, {r0 - pc}^			@ Restore SVC registers
2301da177e4SLinus Torvalds
2311da177e4SLinus Torvalds	.align	5
2321da177e4SLinus Torvalds__pabt_svc:
2331da177e4SLinus Torvalds	svc_entry abt
2341da177e4SLinus Torvalds
2351da177e4SLinus Torvalds	@
2361da177e4SLinus Torvalds	@ re-enable interrupts if appropriate
2371da177e4SLinus Torvalds	@
2381da177e4SLinus Torvalds	mrs	r9, cpsr
2391da177e4SLinus Torvalds	tst	r3, #PSR_I_BIT
2401da177e4SLinus Torvalds	biceq	r9, r9, #PSR_I_BIT
2411da177e4SLinus Torvalds	msr	cpsr_c, r9
2421da177e4SLinus Torvalds
2431da177e4SLinus Torvalds	@
2441da177e4SLinus Torvalds	@ set args, then call main handler
2451da177e4SLinus Torvalds	@
2461da177e4SLinus Torvalds	@  r0 - address of faulting instruction
2471da177e4SLinus Torvalds	@  r1 - pointer to registers on stack
2481da177e4SLinus Torvalds	@
2491da177e4SLinus Torvalds	mov	r0, r2				@ address (pc)
2501da177e4SLinus Torvalds	mov	r1, sp				@ regs
2511da177e4SLinus Torvalds	bl	do_PrefetchAbort		@ call abort handler
2521da177e4SLinus Torvalds
2531da177e4SLinus Torvalds	@
2541da177e4SLinus Torvalds	@ IRQs off again before pulling preserved data off the stack
2551da177e4SLinus Torvalds	@
2561ec42c0cSRussell King	disable_irq
2571da177e4SLinus Torvalds
2581da177e4SLinus Torvalds	@
2591da177e4SLinus Torvalds	@ restore SPSR and restart the instruction
2601da177e4SLinus Torvalds	@
2611da177e4SLinus Torvalds	ldr	r0, [sp, #S_PSR]
2621da177e4SLinus Torvalds	msr	spsr_cxsf, r0
2631da177e4SLinus Torvalds	ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr
2641da177e4SLinus Torvalds
2651da177e4SLinus Torvalds	.align	5
2661da177e4SLinus Torvalds.LCirq:
2671da177e4SLinus Torvalds	.word	__temp_irq
2681da177e4SLinus Torvalds.LCund:
2691da177e4SLinus Torvalds	.word	__temp_und
2701da177e4SLinus Torvalds.LCabt:
2711da177e4SLinus Torvalds	.word	__temp_abt
2721da177e4SLinus Torvalds#ifdef MULTI_ABORT
2731da177e4SLinus Torvalds.LCprocfns:
2741da177e4SLinus Torvalds	.word	processor
2751da177e4SLinus Torvalds#endif
2761da177e4SLinus Torvalds.LCfp:
2771da177e4SLinus Torvalds	.word	fp_enter
2781da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
2791da177e4SLinus Torvalds.LCirq_stat:
2801da177e4SLinus Torvalds	.word	irq_stat
2811da177e4SLinus Torvalds#endif
2821da177e4SLinus Torvalds
2831da177e4SLinus Torvalds/*
2841da177e4SLinus Torvalds * User mode handlers
2851da177e4SLinus Torvalds */
2861da177e4SLinus Torvalds	.macro	usr_entry, sym
2871da177e4SLinus Torvalds	sub	sp, sp, #S_FRAME_SIZE		@ Allocate frame size in one go
2881da177e4SLinus Torvalds	stmia	sp, {r0 - r12}			@ save r0 - r12
2891da177e4SLinus Torvalds	ldr	r7, .LC\sym
2901da177e4SLinus Torvalds	add	r5, sp, #S_PC
2911da177e4SLinus Torvalds	ldmia	r7, {r2 - r4}			@ Get USR pc, cpsr
2921da177e4SLinus Torvalds
2932d2669b6SNicolas Pitre#if __LINUX_ARM_ARCH__ < 6
2942d2669b6SNicolas Pitre	@ make sure our user space atomic helper is aborted
2952d2669b6SNicolas Pitre	cmp	r2, #VIRT_OFFSET
2962d2669b6SNicolas Pitre	bichs	r3, r3, #PSR_Z_BIT
2972d2669b6SNicolas Pitre#endif
2982d2669b6SNicolas Pitre
2991da177e4SLinus Torvalds	@
3001da177e4SLinus Torvalds	@ We are now ready to fill in the remaining blanks on the stack:
3011da177e4SLinus Torvalds	@
3021da177e4SLinus Torvalds	@  r2 - lr_<exception>, already fixed up for correct return/restart
3031da177e4SLinus Torvalds	@  r3 - spsr_<exception>
3041da177e4SLinus Torvalds	@  r4 - orig_r0 (see pt_regs definition in ptrace.h)
3051da177e4SLinus Torvalds	@
3061da177e4SLinus Torvalds	@ Also, separately save sp_usr and lr_usr
3071da177e4SLinus Torvalds	@
3081da177e4SLinus Torvalds	stmia	r5, {r2 - r4}
3091da177e4SLinus Torvalds	stmdb	r5, {sp, lr}^
3101da177e4SLinus Torvalds
3111da177e4SLinus Torvalds	@
3121da177e4SLinus Torvalds	@ Enable the alignment trap while in kernel mode
3131da177e4SLinus Torvalds	@
3141da177e4SLinus Torvalds	alignment_trap r7, r0, __temp_\sym
3151da177e4SLinus Torvalds
3161da177e4SLinus Torvalds	@
3171da177e4SLinus Torvalds	@ Clear FP to mark the first stack frame
3181da177e4SLinus Torvalds	@
3191da177e4SLinus Torvalds	zero_fp
3201da177e4SLinus Torvalds	.endm
3211da177e4SLinus Torvalds
3221da177e4SLinus Torvalds	.align	5
3231da177e4SLinus Torvalds__dabt_usr:
3241da177e4SLinus Torvalds	usr_entry abt
3251da177e4SLinus Torvalds
3261da177e4SLinus Torvalds	@
3271da177e4SLinus Torvalds	@ Call the processor-specific abort handler:
3281da177e4SLinus Torvalds	@
3291da177e4SLinus Torvalds	@  r2 - aborted context pc
3301da177e4SLinus Torvalds	@  r3 - aborted context cpsr
3311da177e4SLinus Torvalds	@
3321da177e4SLinus Torvalds	@ The abort handler must return the aborted address in r0, and
3331da177e4SLinus Torvalds	@ the fault status register in r1.
3341da177e4SLinus Torvalds	@
3351da177e4SLinus Torvalds#ifdef MULTI_ABORT
3361da177e4SLinus Torvalds	ldr	r4, .LCprocfns
3371da177e4SLinus Torvalds	mov	lr, pc
3381da177e4SLinus Torvalds	ldr	pc, [r4]
3391da177e4SLinus Torvalds#else
3401da177e4SLinus Torvalds	bl	CPU_ABORT_HANDLER
3411da177e4SLinus Torvalds#endif
3421da177e4SLinus Torvalds
3431da177e4SLinus Torvalds	@
3441da177e4SLinus Torvalds	@ IRQs on, then call the main handler
3451da177e4SLinus Torvalds	@
3461ec42c0cSRussell King	enable_irq
3471da177e4SLinus Torvalds	mov	r2, sp
3481da177e4SLinus Torvalds	adr	lr, ret_from_exception
3491da177e4SLinus Torvalds	b	do_DataAbort
3501da177e4SLinus Torvalds
3511da177e4SLinus Torvalds	.align	5
3521da177e4SLinus Torvalds__irq_usr:
3531da177e4SLinus Torvalds	usr_entry irq
3541da177e4SLinus Torvalds
355706fdd9fSRussell King	get_thread_info tsk
3561da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
357706fdd9fSRussell King	ldr	r8, [tsk, #TI_PREEMPT]		@ get preempt count
358706fdd9fSRussell King	add	r7, r8, #1			@ increment it
359706fdd9fSRussell King	str	r7, [tsk, #TI_PREEMPT]
3601da177e4SLinus Torvalds#endif
361187a51adSRussell King	irq_handler
3621da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT
363706fdd9fSRussell King	ldr	r0, [tsk, #TI_PREEMPT]
364706fdd9fSRussell King	str	r8, [tsk, #TI_PREEMPT]
3651da177e4SLinus Torvalds	teq	r0, r7
3661da177e4SLinus Torvalds	strne	r0, [r0, -r0]
3671da177e4SLinus Torvalds#endif
3681da177e4SLinus Torvalds	mov	why, #0
3691da177e4SLinus Torvalds	b	ret_to_user
3701da177e4SLinus Torvalds
3711da177e4SLinus Torvalds	.ltorg
3721da177e4SLinus Torvalds
3731da177e4SLinus Torvalds	.align	5
3741da177e4SLinus Torvalds__und_usr:
3751da177e4SLinus Torvalds	usr_entry und
3761da177e4SLinus Torvalds
3771da177e4SLinus Torvalds	tst	r3, #PSR_T_BIT			@ Thumb mode?
3781da177e4SLinus Torvalds	bne	fpundefinstr			@ ignore FP
3791da177e4SLinus Torvalds	sub	r4, r2, #4
3801da177e4SLinus Torvalds
3811da177e4SLinus Torvalds	@
3821da177e4SLinus Torvalds	@ fall through to the emulation code, which returns using r9 if
3831da177e4SLinus Torvalds	@ it has emulated the instruction, or the more conventional lr
3841da177e4SLinus Torvalds	@ if we are to treat this as a real undefined instruction
3851da177e4SLinus Torvalds	@
3861da177e4SLinus Torvalds	@  r0 - instruction
3871da177e4SLinus Torvalds	@
3881da177e4SLinus Torvalds1:	ldrt	r0, [r4]
3891da177e4SLinus Torvalds	adr	r9, ret_from_exception
3901da177e4SLinus Torvalds	adr	lr, fpundefinstr
3911da177e4SLinus Torvalds	@
3921da177e4SLinus Torvalds	@ fallthrough to call_fpe
3931da177e4SLinus Torvalds	@
3941da177e4SLinus Torvalds
3951da177e4SLinus Torvalds/*
3961da177e4SLinus Torvalds * The out of line fixup for the ldrt above.
3971da177e4SLinus Torvalds */
3981da177e4SLinus Torvalds	.section .fixup, "ax"
3991da177e4SLinus Torvalds2:	mov	pc, r9
4001da177e4SLinus Torvalds	.previous
4011da177e4SLinus Torvalds	.section __ex_table,"a"
4021da177e4SLinus Torvalds	.long	1b, 2b
4031da177e4SLinus Torvalds	.previous
4041da177e4SLinus Torvalds
4051da177e4SLinus Torvalds/*
4061da177e4SLinus Torvalds * Check whether the instruction is a co-processor instruction.
4071da177e4SLinus Torvalds * If yes, we need to call the relevant co-processor handler.
4081da177e4SLinus Torvalds *
4091da177e4SLinus Torvalds * Note that we don't do a full check here for the co-processor
4101da177e4SLinus Torvalds * instructions; all instructions with bit 27 set are well
4111da177e4SLinus Torvalds * defined.  The only instructions that should fault are the
4121da177e4SLinus Torvalds * co-processor instructions.  However, we have to watch out
4131da177e4SLinus Torvalds * for the ARM6/ARM7 SWI bug.
4141da177e4SLinus Torvalds *
4151da177e4SLinus Torvalds * Emulators may wish to make use of the following registers:
4161da177e4SLinus Torvalds *  r0  = instruction opcode.
4171da177e4SLinus Torvalds *  r2  = PC+4
4181da177e4SLinus Torvalds *  r10 = this threads thread_info structure.
4191da177e4SLinus Torvalds */
4201da177e4SLinus Torvaldscall_fpe:
4211da177e4SLinus Torvalds	tst	r0, #0x08000000			@ only CDP/CPRT/LDC/STC have bit 27
4221da177e4SLinus Torvalds#if defined(CONFIG_CPU_ARM610) || defined(CONFIG_CPU_ARM710)
4231da177e4SLinus Torvalds	and	r8, r0, #0x0f000000		@ mask out op-code bits
4241da177e4SLinus Torvalds	teqne	r8, #0x0f000000			@ SWI (ARM6/7 bug)?
4251da177e4SLinus Torvalds#endif
4261da177e4SLinus Torvalds	moveq	pc, lr
4271da177e4SLinus Torvalds	get_thread_info r10			@ get current thread
4281da177e4SLinus Torvalds	and	r8, r0, #0x00000f00		@ mask out CP number
4291da177e4SLinus Torvalds	mov	r7, #1
4301da177e4SLinus Torvalds	add	r6, r10, #TI_USED_CP
4311da177e4SLinus Torvalds	strb	r7, [r6, r8, lsr #8]		@ set appropriate used_cp[]
4321da177e4SLinus Torvalds#ifdef CONFIG_IWMMXT
4331da177e4SLinus Torvalds	@ Test if we need to give access to iWMMXt coprocessors
4341da177e4SLinus Torvalds	ldr	r5, [r10, #TI_FLAGS]
4351da177e4SLinus Torvalds	rsbs	r7, r8, #(1 << 8)		@ CP 0 or 1 only
4361da177e4SLinus Torvalds	movcss	r7, r5, lsr #(TIF_USING_IWMMXT + 1)
4371da177e4SLinus Torvalds	bcs	iwmmxt_task_enable
4381da177e4SLinus Torvalds#endif
4391ec42c0cSRussell King	enable_irq
4401da177e4SLinus Torvalds	add	pc, pc, r8, lsr #6
4411da177e4SLinus Torvalds	mov	r0, r0
4421da177e4SLinus Torvalds
4431da177e4SLinus Torvalds	mov	pc, lr				@ CP#0
4441da177e4SLinus Torvalds	b	do_fpe				@ CP#1 (FPE)
4451da177e4SLinus Torvalds	b	do_fpe				@ CP#2 (FPE)
4461da177e4SLinus Torvalds	mov	pc, lr				@ CP#3
4471da177e4SLinus Torvalds	mov	pc, lr				@ CP#4
4481da177e4SLinus Torvalds	mov	pc, lr				@ CP#5
4491da177e4SLinus Torvalds	mov	pc, lr				@ CP#6
4501da177e4SLinus Torvalds	mov	pc, lr				@ CP#7
4511da177e4SLinus Torvalds	mov	pc, lr				@ CP#8
4521da177e4SLinus Torvalds	mov	pc, lr				@ CP#9
4531da177e4SLinus Torvalds#ifdef CONFIG_VFP
4541da177e4SLinus Torvalds	b	do_vfp				@ CP#10 (VFP)
4551da177e4SLinus Torvalds	b	do_vfp				@ CP#11 (VFP)
4561da177e4SLinus Torvalds#else
4571da177e4SLinus Torvalds	mov	pc, lr				@ CP#10 (VFP)
4581da177e4SLinus Torvalds	mov	pc, lr				@ CP#11 (VFP)
4591da177e4SLinus Torvalds#endif
4601da177e4SLinus Torvalds	mov	pc, lr				@ CP#12
4611da177e4SLinus Torvalds	mov	pc, lr				@ CP#13
4621da177e4SLinus Torvalds	mov	pc, lr				@ CP#14 (Debug)
4631da177e4SLinus Torvalds	mov	pc, lr				@ CP#15 (Control)
4641da177e4SLinus Torvalds
4651da177e4SLinus Torvaldsdo_fpe:
4661da177e4SLinus Torvalds	ldr	r4, .LCfp
4671da177e4SLinus Torvalds	add	r10, r10, #TI_FPSTATE		@ r10 = workspace
4681da177e4SLinus Torvalds	ldr	pc, [r4]			@ Call FP module USR entry point
4691da177e4SLinus Torvalds
4701da177e4SLinus Torvalds/*
4711da177e4SLinus Torvalds * The FP module is called with these registers set:
4721da177e4SLinus Torvalds *  r0  = instruction
4731da177e4SLinus Torvalds *  r2  = PC+4
4741da177e4SLinus Torvalds *  r9  = normal "successful" return address
4751da177e4SLinus Torvalds *  r10 = FP workspace
4761da177e4SLinus Torvalds *  lr  = unrecognised FP instruction return address
4771da177e4SLinus Torvalds */
4781da177e4SLinus Torvalds
4791da177e4SLinus Torvalds	.data
4801da177e4SLinus TorvaldsENTRY(fp_enter)
4811da177e4SLinus Torvalds	.word	fpundefinstr
4821da177e4SLinus Torvalds	.text
4831da177e4SLinus Torvalds
4841da177e4SLinus Torvaldsfpundefinstr:
4851da177e4SLinus Torvalds	mov	r0, sp
4861da177e4SLinus Torvalds	adr	lr, ret_from_exception
4871da177e4SLinus Torvalds	b	do_undefinstr
4881da177e4SLinus Torvalds
4891da177e4SLinus Torvalds	.align	5
4901da177e4SLinus Torvalds__pabt_usr:
4911da177e4SLinus Torvalds	usr_entry abt
4921da177e4SLinus Torvalds
4931ec42c0cSRussell King	enable_irq				@ Enable interrupts
4941da177e4SLinus Torvalds	mov	r0, r2				@ address (pc)
4951da177e4SLinus Torvalds	mov	r1, sp				@ regs
4961da177e4SLinus Torvalds	bl	do_PrefetchAbort		@ call abort handler
4971da177e4SLinus Torvalds	/* fall through */
4981da177e4SLinus Torvalds/*
4991da177e4SLinus Torvalds * This is the return code to user mode for abort handlers
5001da177e4SLinus Torvalds */
5011da177e4SLinus TorvaldsENTRY(ret_from_exception)
5021da177e4SLinus Torvalds	get_thread_info tsk
5031da177e4SLinus Torvalds	mov	why, #0
5041da177e4SLinus Torvalds	b	ret_to_user
5051da177e4SLinus Torvalds
5061da177e4SLinus Torvalds/*
5071da177e4SLinus Torvalds * Register switch for ARMv3 and ARMv4 processors
5081da177e4SLinus Torvalds * r0 = previous task_struct, r1 = previous thread_info, r2 = next thread_info
5091da177e4SLinus Torvalds * previous and next are guaranteed not to be the same.
5101da177e4SLinus Torvalds */
5111da177e4SLinus TorvaldsENTRY(__switch_to)
5121da177e4SLinus Torvalds	add	ip, r1, #TI_CPU_SAVE
5131da177e4SLinus Torvalds	ldr	r3, [r2, #TI_TP_VALUE]
5141da177e4SLinus Torvalds	stmia	ip!, {r4 - sl, fp, sp, lr}	@ Store most regs on stack
5151da177e4SLinus Torvalds	ldr	r6, [r2, #TI_CPU_DOMAIN]!
5161da177e4SLinus Torvalds#if defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_IWMMXT)
5171da177e4SLinus Torvalds	mra	r4, r5, acc0
5181da177e4SLinus Torvalds	stmia   ip, {r4, r5}
5191da177e4SLinus Torvalds#endif
5204b0e07a5SNicolas Pitre#if defined(CONFIG_HAS_TLS_REG)
5212d2669b6SNicolas Pitre	mcr	p15, 0, r3, c13, c0, 3		@ set TLS register
5224b0e07a5SNicolas Pitre#elif !defined(CONFIG_TLS_REG_EMUL)
5231da177e4SLinus Torvalds	mov	r4, #0xffff0fff
5242d2669b6SNicolas Pitre	str	r3, [r4, #-15]			@ TLS val at 0xffff0ff0
5252d2669b6SNicolas Pitre#endif
5261da177e4SLinus Torvalds	mcr	p15, 0, r6, c3, c0, 0		@ Set domain register
5271da177e4SLinus Torvalds#ifdef CONFIG_VFP
5281da177e4SLinus Torvalds	@ Always disable VFP so we can lazily save/restore the old
5291da177e4SLinus Torvalds	@ state. This occurs in the context of the previous thread.
5301da177e4SLinus Torvalds	VFPFMRX	r4, FPEXC
5311da177e4SLinus Torvalds	bic	r4, r4, #FPEXC_ENABLE
5321da177e4SLinus Torvalds	VFPFMXR	FPEXC, r4
5331da177e4SLinus Torvalds#endif
5341da177e4SLinus Torvalds#if defined(CONFIG_IWMMXT)
5351da177e4SLinus Torvalds	bl	iwmmxt_task_switch
5361da177e4SLinus Torvalds#elif defined(CONFIG_CPU_XSCALE)
5371da177e4SLinus Torvalds	add	r4, r2, #40			@ cpu_context_save->extra
5381da177e4SLinus Torvalds	ldmib	r4, {r4, r5}
5391da177e4SLinus Torvalds	mar	acc0, r4, r5
5401da177e4SLinus Torvalds#endif
5411da177e4SLinus Torvalds	ldmib	r2, {r4 - sl, fp, sp, pc}	@ Load all regs saved previously
5421da177e4SLinus Torvalds
5431da177e4SLinus Torvalds	__INIT
5442d2669b6SNicolas Pitre
5452d2669b6SNicolas Pitre/*
5462d2669b6SNicolas Pitre * User helpers.
5472d2669b6SNicolas Pitre *
5482d2669b6SNicolas Pitre * These are segment of kernel provided user code reachable from user space
5492d2669b6SNicolas Pitre * at a fixed address in kernel memory.  This is used to provide user space
5502d2669b6SNicolas Pitre * with some operations which require kernel help because of unimplemented
5512d2669b6SNicolas Pitre * native feature and/or instructions in many ARM CPUs. The idea is for
5522d2669b6SNicolas Pitre * this code to be executed directly in user mode for best efficiency but
5532d2669b6SNicolas Pitre * which is too intimate with the kernel counter part to be left to user
5542d2669b6SNicolas Pitre * libraries.  In fact this code might even differ from one CPU to another
5552d2669b6SNicolas Pitre * depending on the available  instruction set and restrictions like on
5562d2669b6SNicolas Pitre * SMP systems.  In other words, the kernel reserves the right to change
5572d2669b6SNicolas Pitre * this code as needed without warning. Only the entry points and their
5582d2669b6SNicolas Pitre * results are guaranteed to be stable.
5592d2669b6SNicolas Pitre *
5602d2669b6SNicolas Pitre * Each segment is 32-byte aligned and will be moved to the top of the high
5612d2669b6SNicolas Pitre * vector page.  New segments (if ever needed) must be added in front of
5622d2669b6SNicolas Pitre * existing ones.  This mechanism should be used only for things that are
5632d2669b6SNicolas Pitre * really small and justified, and not be abused freely.
5642d2669b6SNicolas Pitre *
5652d2669b6SNicolas Pitre * User space is expected to implement those things inline when optimizing
5662d2669b6SNicolas Pitre * for a processor that has the necessary native support, but only if such
5672d2669b6SNicolas Pitre * resulting binaries are already to be incompatible with earlier ARM
5682d2669b6SNicolas Pitre * processors due to the use of unsupported instructions other than what
5692d2669b6SNicolas Pitre * is provided here.  In other words don't make binaries unable to run on
5702d2669b6SNicolas Pitre * earlier processors just for the sake of not using these kernel helpers
5712d2669b6SNicolas Pitre * if your compiled code is not going to use the new instructions for other
5722d2669b6SNicolas Pitre * purpose.
5732d2669b6SNicolas Pitre */
5742d2669b6SNicolas Pitre
5752d2669b6SNicolas Pitre	.align	5
5762d2669b6SNicolas Pitre	.globl	__kuser_helper_start
5772d2669b6SNicolas Pitre__kuser_helper_start:
5782d2669b6SNicolas Pitre
5792d2669b6SNicolas Pitre/*
5802d2669b6SNicolas Pitre * Reference prototype:
5812d2669b6SNicolas Pitre *
5822d2669b6SNicolas Pitre *	int __kernel_cmpxchg(int oldval, int newval, int *ptr)
5832d2669b6SNicolas Pitre *
5842d2669b6SNicolas Pitre * Input:
5852d2669b6SNicolas Pitre *
5862d2669b6SNicolas Pitre *	r0 = oldval
5872d2669b6SNicolas Pitre *	r1 = newval
5882d2669b6SNicolas Pitre *	r2 = ptr
5892d2669b6SNicolas Pitre *	lr = return address
5902d2669b6SNicolas Pitre *
5912d2669b6SNicolas Pitre * Output:
5922d2669b6SNicolas Pitre *
5932d2669b6SNicolas Pitre *	r0 = returned value (zero or non-zero)
5942d2669b6SNicolas Pitre *	C flag = set if r0 == 0, clear if r0 != 0
5952d2669b6SNicolas Pitre *
5962d2669b6SNicolas Pitre * Clobbered:
5972d2669b6SNicolas Pitre *
5982d2669b6SNicolas Pitre *	r3, ip, flags
5992d2669b6SNicolas Pitre *
6002d2669b6SNicolas Pitre * Definition and user space usage example:
6012d2669b6SNicolas Pitre *
6022d2669b6SNicolas Pitre *	typedef int (__kernel_cmpxchg_t)(int oldval, int newval, int *ptr);
6032d2669b6SNicolas Pitre *	#define __kernel_cmpxchg (*(__kernel_cmpxchg_t *)0xffff0fc0)
6042d2669b6SNicolas Pitre *
6052d2669b6SNicolas Pitre * Atomically store newval in *ptr if *ptr is equal to oldval for user space.
6062d2669b6SNicolas Pitre * Return zero if *ptr was changed or non-zero if no exchange happened.
6072d2669b6SNicolas Pitre * The C flag is also set if *ptr was changed to allow for assembly
6082d2669b6SNicolas Pitre * optimization in the calling code.
6092d2669b6SNicolas Pitre *
6102d2669b6SNicolas Pitre * For example, a user space atomic_add implementation could look like this:
6112d2669b6SNicolas Pitre *
6122d2669b6SNicolas Pitre * #define atomic_add(ptr, val) \
6132d2669b6SNicolas Pitre *	({ register unsigned int *__ptr asm("r2") = (ptr); \
6142d2669b6SNicolas Pitre *	   register unsigned int __result asm("r1"); \
6152d2669b6SNicolas Pitre *	   asm volatile ( \
6162d2669b6SNicolas Pitre *	       "1: @ atomic_add\n\t" \
6172d2669b6SNicolas Pitre *	       "ldr	r0, [r2]\n\t" \
6182d2669b6SNicolas Pitre *	       "mov	r3, #0xffff0fff\n\t" \
6192d2669b6SNicolas Pitre *	       "add	lr, pc, #4\n\t" \
6202d2669b6SNicolas Pitre *	       "add	r1, r0, %2\n\t" \
6212d2669b6SNicolas Pitre *	       "add	pc, r3, #(0xffff0fc0 - 0xffff0fff)\n\t" \
6222d2669b6SNicolas Pitre *	       "bcc	1b" \
6232d2669b6SNicolas Pitre *	       : "=&r" (__result) \
6242d2669b6SNicolas Pitre *	       : "r" (__ptr), "rIL" (val) \
6252d2669b6SNicolas Pitre *	       : "r0","r3","ip","lr","cc","memory" ); \
6262d2669b6SNicolas Pitre *	   __result; })
6272d2669b6SNicolas Pitre */
6282d2669b6SNicolas Pitre
6292d2669b6SNicolas Pitre__kuser_cmpxchg:				@ 0xffff0fc0
6302d2669b6SNicolas Pitre
6312d2669b6SNicolas Pitre#if __LINUX_ARM_ARCH__ < 6
6322d2669b6SNicolas Pitre
6332d2669b6SNicolas Pitre#ifdef CONFIG_SMP  /* sanity check */
6342d2669b6SNicolas Pitre#error "CONFIG_SMP on a machine supporting pre-ARMv6 processors?"
6352d2669b6SNicolas Pitre#endif
6362d2669b6SNicolas Pitre
6372d2669b6SNicolas Pitre	/*
6382d2669b6SNicolas Pitre	 * Theory of operation:
6392d2669b6SNicolas Pitre	 *
6402d2669b6SNicolas Pitre	 * We set the Z flag before loading oldval. If ever an exception
6412d2669b6SNicolas Pitre	 * occurs we can not be sure the loaded value will still be the same
6422d2669b6SNicolas Pitre	 * when the exception returns, therefore the user exception handler
6432d2669b6SNicolas Pitre	 * will clear the Z flag whenever the interrupted user code was
6442d2669b6SNicolas Pitre	 * actually from the kernel address space (see the usr_entry macro).
6452d2669b6SNicolas Pitre	 *
6462d2669b6SNicolas Pitre	 * The post-increment on the str is used to prevent a race with an
6472d2669b6SNicolas Pitre	 * exception happening just after the str instruction which would
6482d2669b6SNicolas Pitre	 * clear the Z flag although the exchange was done.
6492d2669b6SNicolas Pitre	 */
6502d2669b6SNicolas Pitre	teq	ip, ip			@ set Z flag
6512d2669b6SNicolas Pitre	ldr	ip, [r2]		@ load current val
6522d2669b6SNicolas Pitre	add	r3, r2, #1		@ prepare store ptr
6532d2669b6SNicolas Pitre	teqeq	ip, r0			@ compare with oldval if still allowed
6542d2669b6SNicolas Pitre	streq	r1, [r3, #-1]!		@ store newval if still allowed
6552d2669b6SNicolas Pitre	subs	r0, r2, r3		@ if r2 == r3 the str occured
6562d2669b6SNicolas Pitre	mov	pc, lr
6572d2669b6SNicolas Pitre
6582d2669b6SNicolas Pitre#else
6592d2669b6SNicolas Pitre
6602d2669b6SNicolas Pitre	ldrex	r3, [r2]
6612d2669b6SNicolas Pitre	subs	r3, r3, r0
6622d2669b6SNicolas Pitre	strexeq	r3, r1, [r2]
6632d2669b6SNicolas Pitre	rsbs	r0, r3, #0
6642d2669b6SNicolas Pitre	mov	pc, lr
6652d2669b6SNicolas Pitre
6662d2669b6SNicolas Pitre#endif
6672d2669b6SNicolas Pitre
6682d2669b6SNicolas Pitre	.align	5
6692d2669b6SNicolas Pitre
6702d2669b6SNicolas Pitre/*
6712d2669b6SNicolas Pitre * Reference prototype:
6722d2669b6SNicolas Pitre *
6732d2669b6SNicolas Pitre *	int __kernel_get_tls(void)
6742d2669b6SNicolas Pitre *
6752d2669b6SNicolas Pitre * Input:
6762d2669b6SNicolas Pitre *
6772d2669b6SNicolas Pitre *	lr = return address
6782d2669b6SNicolas Pitre *
6792d2669b6SNicolas Pitre * Output:
6802d2669b6SNicolas Pitre *
6812d2669b6SNicolas Pitre *	r0 = TLS value
6822d2669b6SNicolas Pitre *
6832d2669b6SNicolas Pitre * Clobbered:
6842d2669b6SNicolas Pitre *
6852d2669b6SNicolas Pitre *	the Z flag might be lost
6862d2669b6SNicolas Pitre *
6872d2669b6SNicolas Pitre * Definition and user space usage example:
6882d2669b6SNicolas Pitre *
6892d2669b6SNicolas Pitre *	typedef int (__kernel_get_tls_t)(void);
6902d2669b6SNicolas Pitre *	#define __kernel_get_tls (*(__kernel_get_tls_t *)0xffff0fe0)
6912d2669b6SNicolas Pitre *
6922d2669b6SNicolas Pitre * Get the TLS value as previously set via the __ARM_NR_set_tls syscall.
6932d2669b6SNicolas Pitre *
6942d2669b6SNicolas Pitre * This could be used as follows:
6952d2669b6SNicolas Pitre *
6962d2669b6SNicolas Pitre * #define __kernel_get_tls() \
6972d2669b6SNicolas Pitre *	({ register unsigned int __val asm("r0"); \
6982d2669b6SNicolas Pitre *         asm( "mov r0, #0xffff0fff; mov lr, pc; sub pc, r0, #31" \
6992d2669b6SNicolas Pitre *	        : "=r" (__val) : : "lr","cc" ); \
7002d2669b6SNicolas Pitre *	   __val; })
7012d2669b6SNicolas Pitre */
7022d2669b6SNicolas Pitre
7032d2669b6SNicolas Pitre__kuser_get_tls:				@ 0xffff0fe0
7042d2669b6SNicolas Pitre
7054b0e07a5SNicolas Pitre#if !defined(CONFIG_HAS_TLS_REG) && !defined(CONFIG_TLS_REG_EMUL)
7062d2669b6SNicolas Pitre
7072d2669b6SNicolas Pitre	ldr	r0, [pc, #(16 - 8)]		@ TLS stored at 0xffff0ff0
7082d2669b6SNicolas Pitre	mov	pc, lr
7092d2669b6SNicolas Pitre
7102d2669b6SNicolas Pitre#else
7112d2669b6SNicolas Pitre
7122d2669b6SNicolas Pitre	mrc	p15, 0, r0, c13, c0, 3		@ read TLS register
7132d2669b6SNicolas Pitre	mov	pc, lr
7142d2669b6SNicolas Pitre
7152d2669b6SNicolas Pitre#endif
7162d2669b6SNicolas Pitre
7172d2669b6SNicolas Pitre	.rep	5
7182d2669b6SNicolas Pitre	.word	0			@ pad up to __kuser_helper_version
7192d2669b6SNicolas Pitre	.endr
7202d2669b6SNicolas Pitre
7212d2669b6SNicolas Pitre/*
7222d2669b6SNicolas Pitre * Reference declaration:
7232d2669b6SNicolas Pitre *
7242d2669b6SNicolas Pitre *	extern unsigned int __kernel_helper_version;
7252d2669b6SNicolas Pitre *
7262d2669b6SNicolas Pitre * Definition and user space usage example:
7272d2669b6SNicolas Pitre *
7282d2669b6SNicolas Pitre *	#define __kernel_helper_version (*(unsigned int *)0xffff0ffc)
7292d2669b6SNicolas Pitre *
7302d2669b6SNicolas Pitre * User space may read this to determine the curent number of helpers
7312d2669b6SNicolas Pitre * available.
7322d2669b6SNicolas Pitre */
7332d2669b6SNicolas Pitre
7342d2669b6SNicolas Pitre__kuser_helper_version:				@ 0xffff0ffc
7352d2669b6SNicolas Pitre	.word	((__kuser_helper_end - __kuser_helper_start) >> 5)
7362d2669b6SNicolas Pitre
7372d2669b6SNicolas Pitre	.globl	__kuser_helper_end
7382d2669b6SNicolas Pitre__kuser_helper_end:
7392d2669b6SNicolas Pitre
7402d2669b6SNicolas Pitre
7411da177e4SLinus Torvalds/*
7421da177e4SLinus Torvalds * Vector stubs.
7431da177e4SLinus Torvalds *
7447933523dSRussell King * This code is copied to 0xffff0200 so we can use branches in the
7457933523dSRussell King * vectors, rather than ldr's.  Note that this code must not
7467933523dSRussell King * exceed 0x300 bytes.
7471da177e4SLinus Torvalds *
7481da177e4SLinus Torvalds * Common stub entry macro:
7491da177e4SLinus Torvalds *   Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
7501da177e4SLinus Torvalds */
7511da177e4SLinus Torvalds	.macro	vector_stub, name, sym, correction=0
7521da177e4SLinus Torvalds	.align	5
7531da177e4SLinus Torvalds
7541da177e4SLinus Torvaldsvector_\name:
7551da177e4SLinus Torvalds	ldr	r13, .LCs\sym
7561da177e4SLinus Torvalds	.if \correction
7571da177e4SLinus Torvalds	sub	lr, lr, #\correction
7581da177e4SLinus Torvalds	.endif
7591da177e4SLinus Torvalds	str	lr, [r13]			@ save lr_IRQ
7601da177e4SLinus Torvalds	mrs	lr, spsr
7611da177e4SLinus Torvalds	str	lr, [r13, #4]			@ save spsr_IRQ
7621da177e4SLinus Torvalds	@
7631da177e4SLinus Torvalds	@ now branch to the relevant MODE handling routine
7641da177e4SLinus Torvalds	@
7651da177e4SLinus Torvalds	mrs	r13, cpsr
7661da177e4SLinus Torvalds	bic	r13, r13, #MODE_MASK
767acaca3c9SRussell King	orr	r13, r13, #SVC_MODE
7681da177e4SLinus Torvalds	msr	spsr_cxsf, r13			@ switch to SVC_32 mode
7691da177e4SLinus Torvalds
7701da177e4SLinus Torvalds	and	lr, lr, #15
7711da177e4SLinus Torvalds	ldr	lr, [pc, lr, lsl #2]
7721da177e4SLinus Torvalds	movs	pc, lr				@ Changes mode and branches
7731da177e4SLinus Torvalds	.endm
7741da177e4SLinus Torvalds
7757933523dSRussell King	.globl	__stubs_start
7761da177e4SLinus Torvalds__stubs_start:
7771da177e4SLinus Torvalds/*
7781da177e4SLinus Torvalds * Interrupt dispatcher
7791da177e4SLinus Torvalds */
7801da177e4SLinus Torvalds	vector_stub	irq, irq, 4
7811da177e4SLinus Torvalds
7821da177e4SLinus Torvalds	.long	__irq_usr			@  0  (USR_26 / USR_32)
7831da177e4SLinus Torvalds	.long	__irq_invalid			@  1  (FIQ_26 / FIQ_32)
7841da177e4SLinus Torvalds	.long	__irq_invalid			@  2  (IRQ_26 / IRQ_32)
7851da177e4SLinus Torvalds	.long	__irq_svc			@  3  (SVC_26 / SVC_32)
7861da177e4SLinus Torvalds	.long	__irq_invalid			@  4
7871da177e4SLinus Torvalds	.long	__irq_invalid			@  5
7881da177e4SLinus Torvalds	.long	__irq_invalid			@  6
7891da177e4SLinus Torvalds	.long	__irq_invalid			@  7
7901da177e4SLinus Torvalds	.long	__irq_invalid			@  8
7911da177e4SLinus Torvalds	.long	__irq_invalid			@  9
7921da177e4SLinus Torvalds	.long	__irq_invalid			@  a
7931da177e4SLinus Torvalds	.long	__irq_invalid			@  b
7941da177e4SLinus Torvalds	.long	__irq_invalid			@  c
7951da177e4SLinus Torvalds	.long	__irq_invalid			@  d
7961da177e4SLinus Torvalds	.long	__irq_invalid			@  e
7971da177e4SLinus Torvalds	.long	__irq_invalid			@  f
7981da177e4SLinus Torvalds
7991da177e4SLinus Torvalds/*
8001da177e4SLinus Torvalds * Data abort dispatcher
8011da177e4SLinus Torvalds * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
8021da177e4SLinus Torvalds */
8031da177e4SLinus Torvalds	vector_stub	dabt, abt, 8
8041da177e4SLinus Torvalds
8051da177e4SLinus Torvalds	.long	__dabt_usr			@  0  (USR_26 / USR_32)
8061da177e4SLinus Torvalds	.long	__dabt_invalid			@  1  (FIQ_26 / FIQ_32)
8071da177e4SLinus Torvalds	.long	__dabt_invalid			@  2  (IRQ_26 / IRQ_32)
8081da177e4SLinus Torvalds	.long	__dabt_svc			@  3  (SVC_26 / SVC_32)
8091da177e4SLinus Torvalds	.long	__dabt_invalid			@  4
8101da177e4SLinus Torvalds	.long	__dabt_invalid			@  5
8111da177e4SLinus Torvalds	.long	__dabt_invalid			@  6
8121da177e4SLinus Torvalds	.long	__dabt_invalid			@  7
8131da177e4SLinus Torvalds	.long	__dabt_invalid			@  8
8141da177e4SLinus Torvalds	.long	__dabt_invalid			@  9
8151da177e4SLinus Torvalds	.long	__dabt_invalid			@  a
8161da177e4SLinus Torvalds	.long	__dabt_invalid			@  b
8171da177e4SLinus Torvalds	.long	__dabt_invalid			@  c
8181da177e4SLinus Torvalds	.long	__dabt_invalid			@  d
8191da177e4SLinus Torvalds	.long	__dabt_invalid			@  e
8201da177e4SLinus Torvalds	.long	__dabt_invalid			@  f
8211da177e4SLinus Torvalds
8221da177e4SLinus Torvalds/*
8231da177e4SLinus Torvalds * Prefetch abort dispatcher
8241da177e4SLinus Torvalds * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
8251da177e4SLinus Torvalds */
8261da177e4SLinus Torvalds	vector_stub	pabt, abt, 4
8271da177e4SLinus Torvalds
8281da177e4SLinus Torvalds	.long	__pabt_usr			@  0 (USR_26 / USR_32)
8291da177e4SLinus Torvalds	.long	__pabt_invalid			@  1 (FIQ_26 / FIQ_32)
8301da177e4SLinus Torvalds	.long	__pabt_invalid			@  2 (IRQ_26 / IRQ_32)
8311da177e4SLinus Torvalds	.long	__pabt_svc			@  3 (SVC_26 / SVC_32)
8321da177e4SLinus Torvalds	.long	__pabt_invalid			@  4
8331da177e4SLinus Torvalds	.long	__pabt_invalid			@  5
8341da177e4SLinus Torvalds	.long	__pabt_invalid			@  6
8351da177e4SLinus Torvalds	.long	__pabt_invalid			@  7
8361da177e4SLinus Torvalds	.long	__pabt_invalid			@  8
8371da177e4SLinus Torvalds	.long	__pabt_invalid			@  9
8381da177e4SLinus Torvalds	.long	__pabt_invalid			@  a
8391da177e4SLinus Torvalds	.long	__pabt_invalid			@  b
8401da177e4SLinus Torvalds	.long	__pabt_invalid			@  c
8411da177e4SLinus Torvalds	.long	__pabt_invalid			@  d
8421da177e4SLinus Torvalds	.long	__pabt_invalid			@  e
8431da177e4SLinus Torvalds	.long	__pabt_invalid			@  f
8441da177e4SLinus Torvalds
8451da177e4SLinus Torvalds/*
8461da177e4SLinus Torvalds * Undef instr entry dispatcher
8471da177e4SLinus Torvalds * Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
8481da177e4SLinus Torvalds */
8491da177e4SLinus Torvalds	vector_stub	und, und
8501da177e4SLinus Torvalds
8511da177e4SLinus Torvalds	.long	__und_usr			@  0 (USR_26 / USR_32)
8521da177e4SLinus Torvalds	.long	__und_invalid			@  1 (FIQ_26 / FIQ_32)
8531da177e4SLinus Torvalds	.long	__und_invalid			@  2 (IRQ_26 / IRQ_32)
8541da177e4SLinus Torvalds	.long	__und_svc			@  3 (SVC_26 / SVC_32)
8551da177e4SLinus Torvalds	.long	__und_invalid			@  4
8561da177e4SLinus Torvalds	.long	__und_invalid			@  5
8571da177e4SLinus Torvalds	.long	__und_invalid			@  6
8581da177e4SLinus Torvalds	.long	__und_invalid			@  7
8591da177e4SLinus Torvalds	.long	__und_invalid			@  8
8601da177e4SLinus Torvalds	.long	__und_invalid			@  9
8611da177e4SLinus Torvalds	.long	__und_invalid			@  a
8621da177e4SLinus Torvalds	.long	__und_invalid			@  b
8631da177e4SLinus Torvalds	.long	__und_invalid			@  c
8641da177e4SLinus Torvalds	.long	__und_invalid			@  d
8651da177e4SLinus Torvalds	.long	__und_invalid			@  e
8661da177e4SLinus Torvalds	.long	__und_invalid			@  f
8671da177e4SLinus Torvalds
8681da177e4SLinus Torvalds	.align	5
8691da177e4SLinus Torvalds
8701da177e4SLinus Torvalds/*=============================================================================
8711da177e4SLinus Torvalds * Undefined FIQs
8721da177e4SLinus Torvalds *-----------------------------------------------------------------------------
8731da177e4SLinus Torvalds * Enter in FIQ mode, spsr = ANY CPSR, lr = ANY PC
8741da177e4SLinus Torvalds * MUST PRESERVE SVC SPSR, but need to switch to SVC mode to show our msg.
8751da177e4SLinus Torvalds * Basically to switch modes, we *HAVE* to clobber one register...  brain
8761da177e4SLinus Torvalds * damage alert!  I don't think that we can execute any code in here in any
8771da177e4SLinus Torvalds * other mode than FIQ...  Ok you can switch to another mode, but you can't
8781da177e4SLinus Torvalds * get out of that mode without clobbering one register.
8791da177e4SLinus Torvalds */
8801da177e4SLinus Torvaldsvector_fiq:
8811da177e4SLinus Torvalds	disable_fiq
8821da177e4SLinus Torvalds	subs	pc, lr, #4
8831da177e4SLinus Torvalds
8841da177e4SLinus Torvalds/*=============================================================================
8851da177e4SLinus Torvalds * Address exception handler
8861da177e4SLinus Torvalds *-----------------------------------------------------------------------------
8871da177e4SLinus Torvalds * These aren't too critical.
8881da177e4SLinus Torvalds * (they're not supposed to happen, and won't happen in 32-bit data mode).
8891da177e4SLinus Torvalds */
8901da177e4SLinus Torvalds
8911da177e4SLinus Torvaldsvector_addrexcptn:
8921da177e4SLinus Torvalds	b	vector_addrexcptn
8931da177e4SLinus Torvalds
8941da177e4SLinus Torvalds/*
8951da177e4SLinus Torvalds * We group all the following data together to optimise
8961da177e4SLinus Torvalds * for CPUs with separate I & D caches.
8971da177e4SLinus Torvalds */
8981da177e4SLinus Torvalds	.align	5
8991da177e4SLinus Torvalds
9001da177e4SLinus Torvalds.LCvswi:
9011da177e4SLinus Torvalds	.word	vector_swi
9021da177e4SLinus Torvalds
9031da177e4SLinus Torvalds.LCsirq:
9041da177e4SLinus Torvalds	.word	__temp_irq
9051da177e4SLinus Torvalds.LCsund:
9061da177e4SLinus Torvalds	.word	__temp_und
9071da177e4SLinus Torvalds.LCsabt:
9081da177e4SLinus Torvalds	.word	__temp_abt
9091da177e4SLinus Torvalds
9107933523dSRussell King	.globl	__stubs_end
9111da177e4SLinus Torvalds__stubs_end:
9121da177e4SLinus Torvalds
9137933523dSRussell King	.equ	stubs_offset, __vectors_start + 0x200 - __stubs_start
9141da177e4SLinus Torvalds
9157933523dSRussell King	.globl	__vectors_start
9167933523dSRussell King__vectors_start:
9171da177e4SLinus Torvalds	swi	SYS_ERROR0
9187933523dSRussell King	b	vector_und + stubs_offset
9197933523dSRussell King	ldr	pc, .LCvswi + stubs_offset
9207933523dSRussell King	b	vector_pabt + stubs_offset
9217933523dSRussell King	b	vector_dabt + stubs_offset
9227933523dSRussell King	b	vector_addrexcptn + stubs_offset
9237933523dSRussell King	b	vector_irq + stubs_offset
9247933523dSRussell King	b	vector_fiq + stubs_offset
9251da177e4SLinus Torvalds
9267933523dSRussell King	.globl	__vectors_end
9277933523dSRussell King__vectors_end:
9281da177e4SLinus Torvalds
9291da177e4SLinus Torvalds	.data
9301da177e4SLinus Torvalds
9311da177e4SLinus Torvalds/*
9321da177e4SLinus Torvalds * Do not reorder these, and do not insert extra data between...
9331da177e4SLinus Torvalds */
9341da177e4SLinus Torvalds
9351da177e4SLinus Torvalds__temp_irq:
9361da177e4SLinus Torvalds	.word	0				@ saved lr_irq
9371da177e4SLinus Torvalds	.word	0				@ saved spsr_irq
9381da177e4SLinus Torvalds	.word	-1				@ old_r0
9391da177e4SLinus Torvalds__temp_und:
9401da177e4SLinus Torvalds	.word	0				@ Saved lr_und
9411da177e4SLinus Torvalds	.word	0				@ Saved spsr_und
9421da177e4SLinus Torvalds	.word	-1				@ old_r0
9431da177e4SLinus Torvalds__temp_abt:
9441da177e4SLinus Torvalds	.word	0				@ Saved lr_abt
9451da177e4SLinus Torvalds	.word	0				@ Saved spsr_abt
9461da177e4SLinus Torvalds	.word	-1				@ old_r0
9471da177e4SLinus Torvalds
9481da177e4SLinus Torvalds	.globl	cr_alignment
9491da177e4SLinus Torvalds	.globl	cr_no_alignment
9501da177e4SLinus Torvaldscr_alignment:
9511da177e4SLinus Torvalds	.space	4
9521da177e4SLinus Torvaldscr_no_alignment:
9531da177e4SLinus Torvalds	.space	4
954