/* *  linux/arch/arm/lib/backtrace.S * *  Copyright (C) 1995, 1996 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * 27/03/03 Ian Molton Clean up CONFIG_CPU * */#include <linux/linkage.h>#include <asm/assembler.h>		.text @ fp is 0 or stack frame #define frame	r4#define next	r5#define save	r6#define mask	r7#define offset	r8 ENTRY(__backtrace)		mov	r1, #0x10		mov	r0, fp ENTRY(c_backtrace) #if !defined(CONFIG_FRAME_POINTER) || !defined(CONFIG_PRINTK)		mov	pc, lr#else 		stmfd	sp!, {r4 - r8, lr}	@ Save an extra register so we have a location...		tst	r1, #0x10		@ 26 or 32-bit?		moveq	mask, #0xfc000003		movne	mask, #0		tst	mask, r0		movne	r0, #0		movs	frame, r01:		moveq	r0, #-2		ldmeqfd	sp!, {r4 - r8, pc} 2:		stmfd	sp!, {pc}		@ calculate offset of PC in STMIA instruction		ldr	r0, [sp], #4		adr	r1, 2b - 4		sub	offset, r0, r1 3:		tst	frame, mask		@ Check for address exceptions...		bne	1b 1001:		ldr	next, [frame, #-12]	@ get fp1002:		ldr	r2, [frame, #-4]	@ get lr1003:		ldr	r3, [frame, #0]		@ get pc		sub	save, r3, offset	@ Correct PC for prefetching		bic	save, save, mask1004:		ldr	r1, [save, #0]		@ get instruction at function		mov	r1, r1, lsr #10		ldr	r3, .Ldsi+4		teq	r1, r3		subeq	save, save, #4		mov	r0, save		bic	r1, r2, mask		bl	dump_backtrace_entry 		ldr	r0, [frame, #-8]	@ get sp		sub	r0, r0, #41005:		ldr	r1, [save, #4]		@ get instruction at function+4		mov	r3, r1, lsr #10		ldr	r2, .Ldsi+4		teq	r3, r2			@ Check for stmia sp!, {args}		addeq	save, save, #4		@ next instruction		bleq	.Ldumpstm 		sub	r0, frame, #161006:		ldr	r1, [save, #4]		@ Get 'stmia sp!, {rlist, fp, ip, lr, pc}' instruction		mov	r3, r1, lsr #10		ldr	r2, .Ldsi		teq	r3, r2		bleq	.Ldumpstm 		/*		 * A zero next framepointer means we're done.		 */		teq	next, #0		ldmeqfd	sp!, {r4 - r8, pc} 		/*		 * The next framepointer must be above the		 * current framepointer.		 */		cmp	next, frame		mov	frame, next		bhi	3b		b	1007f /* * Fixup for LDMDB.  Note that this must not be in the fixup section. */1007:		ldr	r0, =.Lbad		mov	r1, frame		bl	printk		ldmfd	sp!, {r4 - r8, pc}		.ltorg				.section __ex_table,"a"		.align	3		.long	1001b, 1007b		.long	1002b, 1007b		.long	1003b, 1007b		.long	1004b, 1007b		.long	1005b, 1007b		.long	1006b, 1007b		.previous #define instr r4#define reg   r5#define stack r6 .Ldumpstm:	stmfd	sp!, {instr, reg, stack, r7, r8, lr}		mov	stack, r0		mov	instr, r1		mov	reg, #9		mov	r7, #01:		mov	r3, #1		tst	instr, r3, lsl reg		beq	2f		add	r7, r7, #1		teq	r7, #4		moveq	r7, #0		moveq	r3, #'\n'		movne	r3, #' '		ldr	r2, [stack], #-4		mov	r1, reg		adr	r0, .Lfp		bl	printk2:		subs	reg, reg, #1		bpl	1b		teq	r7, #0		adrne	r0, .Lcr		blne	printk		mov	r0, stack		ldmfd	sp!, {instr, reg, stack, r7, r8, pc} .Lfp:		.asciz	" r%d = %08X%c".Lcr:		.asciz	"\n".Lbad:		.asciz	"Backtrace aborted due to bad frame pointer <%p>\n"		.align.Ldsi:		.word	0x00e92dd8 >> 2		.word	0x00e92d00 >> 2 #endif