entry-armv.s

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		mrs	r9, cpsr			@ Enable interrupts if they were
		tst	r3, #I_BIT
		biceq	r9, r9, #I_BIT			@ previously
		msr	cpsr_c, r9
		mov	r0, r2				@ address (pc)
		mov	r1, sp				@ regs
		bl	SYMBOL_NAME(do_PrefetchAbort)	@ call abort handler
		mov	r0, #I_BIT | MODE_SVC
		msr	cpsr_c, r0
		ldr	r0, [sp, #S_PSR]
		msr	spsr, r0
		ldmia	sp, {r0 - pc}^			@ load r0 - pc, cpsr

		.align	5
.LCirq:		.word	__temp_irq
.LCund:		.word	__temp_und
.LCabt:		.word	__temp_abt
#ifdef MULTI_CPU
.LCprocfns:	.word	SYMBOL_NAME(processor)
#endif
.LCfp:		.word	SYMBOL_NAME(fp_enter)

		irq_prio_table

/*
 * User mode handlers
 */
		.align	5
__dabt_usr:	sub	sp, sp, #S_FRAME_SIZE		@ Allocate frame size in one go
		stmia	sp, {r0 - r12}			@ save r0 - r12
		ldr	r7, .LCabt
		add	r5, sp, #S_PC
		ldmia	r7, {r2 - r4}			@ Get USR pc, cpsr
		stmia	r5, {r2 - r4}			@ Save USR pc, cpsr, old_r0
		stmdb	r5, {sp, lr}^
		alignment_trap r7, r7, __temp_abt
		zero_fp
		mov	r0, r2				@ remove once everyones in sync
#ifdef MULTI_CPU
		ldr	r4, .LCprocfns			@ pass r0, r3 to
		mov	lr, pc				@ processor code
		ldr	pc, [r4]			@ call processor specific code
#else
		bl	cpu_data_abort
#endif
		mov	r2, #MODE_SVC
		msr	cpsr_c, r2			@ Enable interrupts
		mov	r2, sp
		adrsvc	al, lr, ret_from_exception
		b	SYMBOL_NAME(do_DataAbort)

		.align	5
__irq_usr:	sub	sp, sp, #S_FRAME_SIZE
		stmia	sp, {r0 - r12}			@ save r0 - r12
		ldr	r4, .LCirq
		add	r8, sp, #S_PC
		ldmia	r4, {r5 - r7}			@ get saved PC, SPSR
		stmia	r8, {r5 - r7}			@ save pc, psr, old_r0
		stmdb	r8, {sp, lr}^
		alignment_trap r4, r7, __temp_irq
		zero_fp
1:		get_irqnr_and_base r0, r6, r5, lr
		movne	r1, sp
		adrsvc	ne, lr, 1b
		@
		@ routine called with r0 = irq number, r1 = struct pt_regs *
		@
		bne	do_IRQ
		mov	why, #0
		get_current_task tsk
		b	ret_to_user

		.align	5
__und_usr:	sub	sp, sp, #S_FRAME_SIZE		@ Allocate frame size in one go
		stmia	sp, {r0 - r12}			@ Save r0 - r12
		ldr	r4, .LCund
		add	r8, sp, #S_PC
		ldmia	r4, {r5 - r7}
		stmia	r8, {r5 - r7}			@ Save USR pc, cpsr, old_r0
		stmdb	r8, {sp, lr}^			@ Save user sp, lr
		alignment_trap r4, r7, __temp_und
		zero_fp
		adrsvc	al, r9, ret_from_exception	@ r9  = normal FP return
		adrsvc	al, lr, fpundefinstr		@ lr  = undefined instr return

call_fpe:	get_current_task r10
		mov	r8, #1
		strb	r8, [r10, #TSK_USED_MATH]	@ set current->used_math
		ldr	r4, .LCfp
		add	r10, r10, #TSS_FPESAVE		@ r10 = workspace
		ldr	pc, [r4]			@ Call FP module USR entry point

fpundefinstr:	mov	r0, #MODE_SVC
		msr	cpsr_c, r0			@ Enable interrupts
		mov	r0, lr
		mov	r1, sp
		adrsvc	al, lr, ret_from_exception
		b	SYMBOL_NAME(do_undefinstr)

		.align	5
__pabt_usr:	sub	sp, sp, #S_FRAME_SIZE		@ Allocate frame size in one go
		stmia	sp, {r0 - r12}			@ Save r0 - r12
		ldr	r4, .LCabt
		add	r8, sp, #S_PC
		ldmia	r4, {r5 - r7}			@ Get USR pc, cpsr
		stmia	r8, {r5 - r7}			@ Save USR pc, cpsr, old_r0
		stmdb	r8, {sp, lr}^			@ Save sp_usr lr_usr
		alignment_trap r4, r7, __temp_abt
		zero_fp
		mov	r0, #MODE_SVC
		msr	cpsr_c, r0			@ Enable interrupts
		mov	r0, r5				@ address (pc)
		mov	r1, sp				@ regs
		bl	SYMBOL_NAME(do_PrefetchAbort)	@ call abort handler
		/* fall through */
/*
 * This is the return code to user mode for abort handlers
 */
ENTRY(ret_from_exception)
		get_current_task tsk
		mov	why, #0
		b	ret_to_user

		.data
ENTRY(fp_enter)
		.word	fpe_not_present
		.text
/*
 * Register switch for ARMv3 and ARMv4 processors
 * r0 = previous, r1 = next, return previous.
 * previous and next are guaranteed not to be the same.
 */
ENTRY(__switch_to)
		stmfd	sp!, {r4 - sl, fp, lr}		@ Store most regs on stack
		mrs	ip, cpsr
		str	ip, [sp, #-4]!			@ Save cpsr_SVC
#ifdef CONFIG_CPU_XSCALE
		mra	r4, r5, acc0
		stmfd	sp!, {r4, r5}
#endif
		str	sp, [r0, #TSS_SAVE]		@ Save sp_SVC
		ldr	sp, [r1, #TSS_SAVE]		@ Get saved sp_SVC
		ldr	r2, [r1, #TSS_DOMAIN]
#ifdef CONFIG_CPU_XSCALE
		ldmfd	sp!, {r4, r5}
		mar	acc0, r4, r5
#endif
		ldr	ip, [sp], #4
		mcr	p15, 0, r2, c3, c0		@ Set domain register
		msr	spsr, ip			@ Save tasks CPSR into SPSR for this return
		ldmfd	sp!, {r4 - sl, fp, pc}^		@ Load all regs saved previously

		.section ".text.init",#alloc,#execinstr
/*
 * Vector stubs.  NOTE that we only align 'vector_IRQ' to a cache line boundary,
 * and we rely on each stub being exactly 48 (1.5 cache lines) in size.  This
 * means that we only ever load two cache lines for this code, or one if we're
 * lucky.  We also copy this code to 0x200 so that we can use branches in the
 * vectors, rather than ldr's.
 */
		.align	5
__stubs_start:
/*
 * Interrupt dispatcher
 * Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
 */
vector_IRQ:	@
		@ save mode specific registers
		@
		ldr	r13, .LCsirq
		sub	lr, lr, #4
		str	lr, [r13]			@ save lr_IRQ
		mrs	lr, spsr
		str	lr, [r13, #4]			@ save spsr_IRQ
		@
		@ now branch to the relevent MODE handling routine
		@
		mov	r13, #I_BIT | MODE_SVC
		msr	spsr_c, r13			@ switch to SVC_32 mode

		and	lr, lr, #15
		ldr	lr, [pc, lr, lsl #2]
		movs	pc, lr				@ Changes mode and branches

.LCtab_irq:	.word	__irq_usr			@  0  (USR_26 / USR_32)
		.word	__irq_invalid			@  1  (FIQ_26 / FIQ_32)
		.word	__irq_invalid			@  2  (IRQ_26 / IRQ_32)
		.word	__irq_svc			@  3  (SVC_26 / SVC_32)
		.word	__irq_invalid			@  4
		.word	__irq_invalid			@  5
		.word	__irq_invalid			@  6
		.word	__irq_invalid			@  7
		.word	__irq_invalid			@  8
		.word	__irq_invalid			@  9
		.word	__irq_invalid			@  a
		.word	__irq_invalid			@  b
		.word	__irq_invalid			@  c
		.word	__irq_invalid			@  d
		.word	__irq_invalid			@  e
		.word	__irq_invalid			@  f

		.align	5

/*
 * Data abort dispatcher - dispatches it to the correct handler for the processor mode
 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
 */
vector_data:	@
		@ save mode specific registers
		@
		ldr	r13, .LCsabt
		sub	lr, lr, #8
		str	lr, [r13]
		mrs	lr, spsr
		str	lr, [r13, #4]
		@
		@ now branch to the relevent MODE handling routine
		@
		mov	r13, #I_BIT | MODE_SVC
		msr	spsr_c, r13			@ switch to SVC_32 mode

		and	lr, lr, #15
		ldr	lr, [pc, lr, lsl #2]
		movs	pc, lr				@ Changes mode and branches

.LCtab_dabt:	.word	__dabt_usr			@  0  (USR_26 / USR_32)
		.word	__dabt_invalid			@  1  (FIQ_26 / FIQ_32)
		.word	__dabt_invalid			@  2  (IRQ_26 / IRQ_32)
		.word	__dabt_svc			@  3  (SVC_26 / SVC_32)
		.word	__dabt_invalid			@  4
		.word	__dabt_invalid			@  5
		.word	__dabt_invalid			@  6
		.word	__dabt_invalid			@  7
		.word	__dabt_invalid			@  8
		.word	__dabt_invalid			@  9
		.word	__dabt_invalid			@  a
		.word	__dabt_invalid			@  b
		.word	__dabt_invalid			@  c
		.word	__dabt_invalid			@  d
		.word	__dabt_invalid			@  e
		.word	__dabt_invalid			@  f

		.align	5

/*
 * Prefetch abort dispatcher - dispatches it to the correct handler for the processor mode
 * Enter in ABT mode, spsr = USR CPSR, lr = USR PC
 */
vector_prefetch:
		@
		@ save mode specific registers
		@
		ldr	r13, .LCsabt
		sub	lr, lr, #4
		str	lr, [r13]			@ save lr_ABT
		mrs	lr, spsr
		str	lr, [r13, #4]			@ save spsr_ABT
		@
		@ now branch to the relevent MODE handling routine
		@
		mov	r13, #I_BIT | MODE_SVC
		msr	spsr_c, r13			@ switch to SVC_32 mode

		ands	lr, lr, #15
		ldr	lr, [pc, lr, lsl #2]
		movs	pc, lr

.LCtab_pabt:	.word	__pabt_usr			@  0 (USR_26 / USR_32)
		.word	__pabt_invalid			@  1 (FIQ_26 / FIQ_32)
		.word	__pabt_invalid			@  2 (IRQ_26 / IRQ_32)
		.word	__pabt_svc			@  3 (SVC_26 / SVC_32)
		.word	__pabt_invalid			@  4
		.word	__pabt_invalid			@  5
		.word	__pabt_invalid			@  6
		.word	__pabt_invalid			@  7
		.word	__pabt_invalid			@  8
		.word	__pabt_invalid			@  9
		.word	__pabt_invalid			@  a
		.word	__pabt_invalid			@  b
		.word	__pabt_invalid			@  c
		.word	__pabt_invalid			@  d
		.word	__pabt_invalid			@  e
		.word	__pabt_invalid			@  f

		.align	5

/*
 * Undef instr entry dispatcher - dispatches it to the correct handler for the processor mode
 * Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC
 */
vector_undefinstr:
		@
		@ save mode specific registers
		@
		ldr	r13, .LCsund
		str	lr, [r13]			@ save lr_UND
		mrs	lr, spsr
		str	lr, [r13, #4]			@ save spsr_UND
		@
		@ now branch to the relevent MODE handling routine
		@
		mov	r13, #I_BIT | MODE_SVC
		msr	spsr_c, r13			@ switch to SVC_32 mode

		and	lr, lr, #15
		ldr	lr, [pc, lr, lsl #2]
		movs	pc, lr				@ Changes mode and branches

.LCtab_und:	.word	__und_usr			@  0 (USR_26 / USR_32)
		.word	__und_invalid			@  1 (FIQ_26 / FIQ_32)
		.word	__und_invalid			@  2 (IRQ_26 / IRQ_32)
		.word	__und_svc			@  3 (SVC_26 / SVC_32)
		.word	__und_invalid			@  4
		.word	__und_invalid			@  5
		.word	__und_invalid			@  6
		.word	__und_invalid			@  7
		.word	__und_invalid			@  8
		.word	__und_invalid			@  9
		.word	__und_invalid			@  a
		.word	__und_invalid			@  b
		.word	__und_invalid			@  c
		.word	__und_invalid			@  d
		.word	__und_invalid			@  e
		.word	__und_invalid			@  f

		.align	5

/*=============================================================================
 * Undefined FIQs
 *-----------------------------------------------------------------------------
 * Enter in FIQ mode, spsr = ANY CPSR, lr = ANY PC
 * MUST PRESERVE SVC SPSR, but need to switch to SVC mode to show our msg.
 * Basically to switch modes, we *HAVE* to clobber one register...  brain
 * damage alert!  I don't think that we can execute any code in here in any
 * other mode than FIQ...  Ok you can switch to another mode, but you can't
 * get out of that mode without clobbering one register.
 */
vector_FIQ:	disable_fiq
		subs	pc, lr, #4

/*=============================================================================
 * Address exception handler
 *-----------------------------------------------------------------------------
 * These aren't too critical.
 * (they're not supposed to happen, and won't happen in 32-bit data mode).
 */

vector_addrexcptn:
		b	vector_addrexcptn

/*
 * We group all the following data together to optimise
 * for CPUs with separate I & D caches.
 */
		.align	5

.LCvswi:	.word	vector_swi

.LCsirq:	.word	__temp_irq
.LCsund:	.word	__temp_und
.LCsabt:	.word	__temp_abt

__stubs_end:

		.equ	__real_stubs_start, .LCvectors + 0x200

.LCvectors:	swi	SYS_ERROR0
		b	__real_stubs_start + (vector_undefinstr - __stubs_start)
		ldr	pc, __real_stubs_start + (.LCvswi - __stubs_start)
		b	__real_stubs_start + (vector_prefetch - __stubs_start)
		b	__real_stubs_start + (vector_data - __stubs_start)
		b	__real_stubs_start + (vector_addrexcptn - __stubs_start)
		b	__real_stubs_start + (vector_IRQ - __stubs_start)
		b	__real_stubs_start + (vector_FIQ - __stubs_start)

ENTRY(__trap_init)
		stmfd	sp!, {r4 - r6, lr}

		adr	r1, .LCvectors			@ set up the vectors
		ldmia	r1, {r1, r2, r3, r4, r5, r6, ip, lr}
		stmia	r0, {r1, r2, r3, r4, r5, r6, ip, lr}

		add	r2, r0, #0x200
		adr	r0, __stubs_start		@ copy stubs to 0x200
		adr	r1, __stubs_end
1:		ldr	r3, [r0], #4
		str	r3, [r2], #4
		cmp	r0, r1
		blt	1b
		LOADREGS(fd, sp!, {r4 - r6, pc})

		.data

/*
 * Do not reorder these, and do not insert extra data between...
 */

__temp_irq:	.word	0				@ saved lr_irq
		.word	0				@ saved spsr_irq
		.word	-1				@ old_r0
__temp_und:	.word	0				@ Saved lr_und
		.word	0				@ Saved spsr_und
		.word	-1				@ old_r0
__temp_abt:	.word	0				@ Saved lr_abt
		.word	0				@ Saved spsr_abt
		.word	-1				@ old_r0

		.globl	SYMBOL_NAME(cr_alignment)
		.globl	SYMBOL_NAME(cr_no_alignment)
SYMBOL_NAME(cr_alignment):
		.space	4
SYMBOL_NAME(cr_no_alignment):
		.space	4