xref: /openbmc/u-boot/arch/arm/cpu/arm1176/start.S (revision 5a75e121)
1/*
2 *  armboot - Startup Code for ARM1176 CPU-core
3 *
4 * Copyright (c) 2007	Samsung Electronics
5 *
6 * Copyright (C) 2008
7 * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
8 *
9 * See file CREDITS for list of people who contributed to this
10 * project.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License as
14 * published by the Free Software Foundation; either version 2 of
15 * the License, or (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25 * MA 02111-1307 USA
26 *
27 * 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
28 * 2007-09-21 - Added MoviNAND and OneNAND boot codes by
29 * jsgood (jsgood.yang@samsung.com)
30 * Base codes by scsuh (sc.suh)
31 */
32
33#include <config.h>
34#include <version.h>
35#ifdef CONFIG_ENABLE_MMU
36#include <asm/proc/domain.h>
37#endif
38
39#if !defined(CONFIG_ENABLE_MMU) && !defined(CONFIG_SYS_PHY_UBOOT_BASE)
40#define CONFIG_SYS_PHY_UBOOT_BASE	CONFIG_SYS_UBOOT_BASE
41#endif
42
43/*
44 *************************************************************************
45 *
46 * Jump vector table as in table 3.1 in [1]
47 *
48 *************************************************************************
49 */
50
51.globl _start
52_start: b	reset
53#ifndef CONFIG_NAND_SPL
54	ldr	pc, _undefined_instruction
55	ldr	pc, _software_interrupt
56	ldr	pc, _prefetch_abort
57	ldr	pc, _data_abort
58	ldr	pc, _not_used
59	ldr	pc, _irq
60	ldr	pc, _fiq
61
62_undefined_instruction:
63	.word undefined_instruction
64_software_interrupt:
65	.word software_interrupt
66_prefetch_abort:
67	.word prefetch_abort
68_data_abort:
69	.word data_abort
70_not_used:
71	.word not_used
72_irq:
73	.word irq
74_fiq:
75	.word fiq
76_pad:
77	.word 0x12345678 /* now 16*4=64 */
78#else
79	. = _start + 64
80#endif
81
82.global _end_vect
83_end_vect:
84	.balignl 16,0xdeadbeef
85/*
86 *************************************************************************
87 *
88 * Startup Code (reset vector)
89 *
90 * do important init only if we don't start from memory!
91 * setup Memory and board specific bits prior to relocation.
92 * relocate armboot to ram
93 * setup stack
94 *
95 *************************************************************************
96 */
97
98.globl _TEXT_BASE
99_TEXT_BASE:
100	.word	CONFIG_SYS_TEXT_BASE
101
102/*
103 * Below variable is very important because we use MMU in U-Boot.
104 * Without it, we cannot run code correctly before MMU is ON.
105 * by scsuh.
106 */
107_TEXT_PHY_BASE:
108	.word	CONFIG_SYS_PHY_UBOOT_BASE
109
110#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
111.globl _armboot_start
112_armboot_start:
113	.word _start
114#endif
115
116/*
117 * These are defined in the board-specific linker script.
118 */
119.globl _bss_start
120_bss_start:
121	.word __bss_start
122
123.globl _bss_end
124_bss_end:
125	.word _end
126
127#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
128/* IRQ stack memory (calculated at run-time) + 8 bytes */
129.globl IRQ_STACK_START_IN
130IRQ_STACK_START_IN:
131	.word	0x0badc0de
132
133.globl _datarel_start
134_datarel_start:
135	.word __datarel_start
136
137.globl _datarelrolocal_start
138_datarelrolocal_start:
139	.word __datarelrolocal_start
140
141.globl _datarellocal_start
142_datarellocal_start:
143	.word __datarellocal_start
144
145.globl _datarelro_start
146_datarelro_start:
147	.word __datarelro_start
148
149.globl _got_start
150_got_start:
151	.word __got_start
152
153.globl _got_end
154_got_end:
155	.word __got_end
156
157/*
158 * the actual reset code
159 */
160
161reset:
162	/*
163	 * set the cpu to SVC32 mode
164	 */
165	mrs	r0, cpsr
166	bic	r0, r0, #0x3f
167	orr	r0, r0, #0xd3
168	msr	cpsr, r0
169
170/*
171 *************************************************************************
172 *
173 * CPU_init_critical registers
174 *
175 * setup important registers
176 * setup memory timing
177 *
178 *************************************************************************
179 */
180	/*
181	 * we do sys-critical inits only at reboot,
182	 * not when booting from ram!
183	 */
184cpu_init_crit:
185	/*
186	 * When booting from NAND - it has definitely been a reset, so, no need
187	 * to flush caches and disable the MMU
188	 */
189#ifndef CONFIG_NAND_SPL
190	/*
191	 * flush v4 I/D caches
192	 */
193	mov	r0, #0
194	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
195	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
196
197	/*
198	 * disable MMU stuff and caches
199	 */
200	mrc	p15, 0, r0, c1, c0, 0
201	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
202	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
203	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
204	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
205
206	/* Prepare to disable the MMU */
207	adr	r2, mmu_disable_phys
208	sub	r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - CONFIG_SYS_TEXT_BASE)
209	b	mmu_disable
210
211	.align 5
212	/* Run in a single cache-line */
213mmu_disable:
214	mcr	p15, 0, r0, c1, c0, 0
215	nop
216	nop
217	mov	pc, r2
218mmu_disable_phys:
219
220#ifdef CONFIG_DISABLE_TCM
221	/*
222	 * Disable the TCMs
223	 */
224	mrc	p15, 0, r0, c0, c0, 2	/* Return TCM details */
225	cmp	r0, #0
226	beq	skip_tcmdisable
227	mov	r1, #0
228	mov	r2, #1
229	tst	r0, r2
230	mcrne	p15, 0, r1, c9, c1, 1	/* Disable Instruction TCM if present*/
231	tst	r0, r2, LSL #16
232	mcrne	p15, 0, r1, c9, c1, 0	/* Disable Data TCM if present*/
233skip_tcmdisable:
234#endif
235#endif
236
237#ifdef CONFIG_PERIPORT_REMAP
238	/* Peri port setup */
239	ldr	r0, =CONFIG_PERIPORT_BASE
240	orr	r0, r0, #CONFIG_PERIPORT_SIZE
241	mcr	p15,0,r0,c15,c2,4
242#endif
243
244	/*
245	 * Go setup Memory and board specific bits prior to relocation.
246	 */
247	bl	lowlevel_init		/* go setup pll,mux,memory */
248
249/* Set stackpointer in internal RAM to call board_init_f */
250call_board_init_f:
251	ldr	sp, =(CONFIG_SYS_INIT_SP_ADDR)
252	ldr	r0,=0x00000000
253	bl	board_init_f
254
255/*------------------------------------------------------------------------------*/
256
257/*
258 * void relocate_code (addr_sp, gd, addr_moni)
259 *
260 * This "function" does not return, instead it continues in RAM
261 * after relocating the monitor code.
262 *
263 */
264	.globl	relocate_code
265relocate_code:
266	mov	r4, r0	/* save addr_sp */
267	mov	r5, r1	/* save addr of gd */
268	mov	r6, r2	/* save addr of destination */
269	mov	r7, r2	/* save addr of destination */
270
271	/* Set up the stack						    */
272stack_setup:
273	mov	sp, r4
274
275	adr	r0, _start
276	ldr	r2, _TEXT_BASE
277	ldr	r3, _bss_start
278	sub	r2, r3, r2		/* r2 <- size of armboot	    */
279	add	r2, r0, r2		/* r2 <- source end address	    */
280	cmp	r0, r6
281	beq	clear_bss
282
283#ifndef CONFIG_SKIP_RELOCATE_UBOOT
284copy_loop:
285	ldmia	r0!, {r9-r10}		/* copy from source address [r0]    */
286	stmia	r6!, {r9-r10}		/* copy to   target address [r1]    */
287	cmp	r0, r2			/* until source end address [r2]    */
288	blo	copy_loop
289
290#ifndef CONFIG_PRELOADER
291	/* fix got entries */
292	ldr	r1, _TEXT_BASE		/* Text base */
293	mov	r0, r7			/* reloc addr */
294	ldr	r2, _got_start		/* addr in Flash */
295	ldr	r3, _got_end		/* addr in Flash */
296	sub	r3, r3, r1
297	add	r3, r3, r0
298	sub	r2, r2, r1
299	add	r2, r2, r0
300
301fixloop:
302	ldr	r4, [r2]
303	sub	r4, r4, r1
304	add	r4, r4, r0
305	str	r4, [r2]
306	add	r2, r2, #4
307	cmp	r2, r3
308	bne	fixloop
309#endif
310#endif	/* #ifndef CONFIG_SKIP_RELOCATE_UBOOT */
311
312#ifdef CONFIG_ENABLE_MMU
313enable_mmu:
314	/* enable domain access */
315	ldr	r5, =0x0000ffff
316	mcr	p15, 0, r5, c3, c0, 0	/* load domain access register */
317
318	/* Set the TTB register */
319	ldr	r0, _mmu_table_base
320	ldr	r1, =CONFIG_SYS_PHY_UBOOT_BASE
321	ldr	r2, =0xfff00000
322	bic	r0, r0, r2
323	orr	r1, r0, r1
324	mcr	p15, 0, r1, c2, c0, 0
325
326	/* Enable the MMU */
327	mrc	p15, 0, r0, c1, c0, 0
328	orr	r0, r0, #1		/* Set CR_M to enable MMU */
329
330	/* Prepare to enable the MMU */
331	adr	r1, skip_hw_init
332	and	r1, r1, #0x3fc
333	ldr	r2, _TEXT_BASE
334	ldr	r3, =0xfff00000
335	and	r2, r2, r3
336	orr	r2, r2, r1
337	b	mmu_enable
338
339	.align 5
340	/* Run in a single cache-line */
341mmu_enable:
342
343	mcr	p15, 0, r0, c1, c0, 0
344	nop
345	nop
346	mov	pc, r2
347skip_hw_init:
348#endif
349
350clear_bss:
351#ifndef CONFIG_PRELOADER
352	ldr	r0, _bss_start
353	ldr	r1, _bss_end
354	ldr	r3, _TEXT_BASE		/* Text base */
355	mov	r4, r7			/* reloc addr */
356	sub	r0, r0, r3
357	add	r0, r0, r4
358	sub	r1, r1, r3
359	add	r1, r1, r4
360	mov	r2, #0x00000000		/* clear			    */
361
362clbss_l:str	r2, [r0]		/* clear loop...		    */
363	add	r0, r0, #4
364	cmp	r0, r1
365	bne	clbss_l
366
367	bl coloured_LED_init
368	bl red_LED_on
369#endif
370
371/*
372 * We are done. Do not return, instead branch to second part of board
373 * initialization, now running from RAM.
374 */
375#ifdef CONFIG_NAND_SPL
376	ldr     pc, _nand_boot
377
378_nand_boot: .word nand_boot
379#else
380	ldr	r0, _TEXT_BASE
381	ldr	r2, _board_init_r
382	sub	r2, r2, r0
383	add	r2, r2, r7	/* position from board_init_r in RAM */
384	/* setup parameters for board_init_r */
385	mov	r0, r5		/* gd_t */
386	mov	r1, r7		/* dest_addr */
387	/* jump to it ... */
388	mov	lr, r2
389	mov	pc, lr
390
391_board_init_r: .word board_init_r
392#endif
393
394#else /* #if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) */
395
396/*
397 * the actual reset code
398 */
399
400reset:
401	/*
402	 * set the cpu to SVC32 mode
403	 */
404	mrs	r0, cpsr
405	bic	r0, r0, #0x3f
406	orr	r0, r0, #0xd3
407	msr	cpsr, r0
408
409/*
410 *************************************************************************
411 *
412 * CPU_init_critical registers
413 *
414 * setup important registers
415 * setup memory timing
416 *
417 *************************************************************************
418 */
419	/*
420	 * we do sys-critical inits only at reboot,
421	 * not when booting from ram!
422	 */
423cpu_init_crit:
424	/*
425	 * When booting from NAND - it has definitely been a reset, so, no need
426	 * to flush caches and disable the MMU
427	 */
428#ifndef CONFIG_NAND_SPL
429	/*
430	 * flush v4 I/D caches
431	 */
432	mov	r0, #0
433	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
434	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
435
436	/*
437	 * disable MMU stuff and caches
438	 */
439	mrc	p15, 0, r0, c1, c0, 0
440	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
441	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
442	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
443	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
444
445	/* Prepare to disable the MMU */
446	adr	r2, mmu_disable_phys
447	sub	r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - CONFIG_SYS_TEXT_BASE)
448	b	mmu_disable
449
450	.align 5
451	/* Run in a single cache-line */
452mmu_disable:
453	mcr	p15, 0, r0, c1, c0, 0
454	nop
455	nop
456	mov	pc, r2
457mmu_disable_phys:
458
459#ifdef CONFIG_DISABLE_TCM
460	/*
461	 * Disable the TCMs
462	 */
463	mrc	p15, 0, r0, c0, c0, 2	/* Return TCM details */
464	cmp	r0, #0
465	beq	skip_tcmdisable
466	mov	r1, #0
467	mov	r2, #1
468	tst	r0, r2
469	mcrne	p15, 0, r1, c9, c1, 1	/* Disable Instruction TCM if present*/
470	tst	r0, r2, LSL #16
471	mcrne	p15, 0, r1, c9, c1, 0	/* Disable Data TCM if present*/
472skip_tcmdisable:
473#endif
474#endif
475
476#ifdef CONFIG_PERIPORT_REMAP
477	/* Peri port setup */
478	ldr	r0, =CONFIG_PERIPORT_BASE
479	orr	r0, r0, #CONFIG_PERIPORT_SIZE
480	mcr	p15,0,r0,c15,c2,4
481#endif
482
483	/*
484	 * Go setup Memory and board specific bits prior to relocation.
485	 */
486	bl	lowlevel_init		/* go setup pll,mux,memory */
487
488#ifndef CONFIG_SKIP_RELOCATE_UBOOT
489relocate:				/* relocate U-Boot to RAM	    */
490	adr	r0, _start		/* r0 <- current position of code   */
491	ldr	r1, _TEXT_BASE		/* test if we run from flash or RAM */
492	cmp     r0, r1                  /* don't reloc during debug         */
493	beq     stack_setup
494
495	ldr	r2, _armboot_start
496	ldr	r3, _bss_start
497	sub	r2, r3, r2		/* r2 <- size of armboot            */
498	add	r2, r0, r2		/* r2 <- source end address         */
499
500copy_loop:
501	ldmia	r0!, {r3-r10}		/* copy from source address [r0]    */
502	stmia	r1!, {r3-r10}		/* copy to   target address [r1]    */
503	cmp	r0, r2			/* until source end address [r2]    */
504	blo	copy_loop
505#endif	/* CONFIG_SKIP_RELOCATE_UBOOT */
506
507#ifdef CONFIG_ENABLE_MMU
508enable_mmu:
509	/* enable domain access */
510	ldr	r5, =0x0000ffff
511	mcr	p15, 0, r5, c3, c0, 0	/* load domain access register */
512
513	/* Set the TTB register */
514	ldr	r0, _mmu_table_base
515	ldr	r1, =CONFIG_SYS_PHY_UBOOT_BASE
516	ldr	r2, =0xfff00000
517	bic	r0, r0, r2
518	orr	r1, r0, r1
519	mcr	p15, 0, r1, c2, c0, 0
520
521	/* Enable the MMU */
522	mrc	p15, 0, r0, c1, c0, 0
523	orr	r0, r0, #1		/* Set CR_M to enable MMU */
524
525	/* Prepare to enable the MMU */
526	adr	r1, skip_hw_init
527	and	r1, r1, #0x3fc
528	ldr	r2, _TEXT_BASE
529	ldr	r3, =0xfff00000
530	and	r2, r2, r3
531	orr	r2, r2, r1
532	b	mmu_enable
533
534	.align 5
535	/* Run in a single cache-line */
536mmu_enable:
537
538	mcr	p15, 0, r0, c1, c0, 0
539	nop
540	nop
541	mov	pc, r2
542skip_hw_init:
543#endif
544
545	/* Set up the stack						    */
546stack_setup:
547	ldr	r0, =CONFIG_SYS_UBOOT_BASE	/* base of copy in DRAM	    */
548	sub	r0, r0, #CONFIG_SYS_MALLOC_LEN	/* malloc area                      */
549	sub	r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo                        */
550	sub	sp, r0, #12		/* leave 3 words for abort-stack    */
551	bic	sp, sp, #7		/* 8-byte alignment for ABI compliance */
552
553clear_bss:
554	ldr	r0, _bss_start		/* find start of bss segment        */
555	ldr	r1, _bss_end		/* stop here                        */
556	mov 	r2, #0			/* clear                            */
557
558clbss_l:
559	str	r2, [r0]		/* clear loop...                    */
560	add	r0, r0, #4
561	cmp	r0, r1
562	blo	clbss_l
563
564#ifndef CONFIG_NAND_SPL
565	ldr	pc, _start_armboot
566
567_start_armboot:
568	.word start_armboot
569#else
570	b	nand_boot
571/*	.word nand_boot*/
572#endif
573
574#endif /* #if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) */
575
576#ifdef CONFIG_ENABLE_MMU
577_mmu_table_base:
578	.word mmu_table
579#endif
580
581#ifndef CONFIG_NAND_SPL
582/*
583 * we assume that cache operation is done before. (eg. cleanup_before_linux())
584 * actually, we don't need to do anything about cache if not use d-cache in
585 * U-Boot. So, in this function we clean only MMU. by scsuh
586 *
587 * void	theLastJump(void *kernel, int arch_num, uint boot_params);
588 */
589#ifdef CONFIG_ENABLE_MMU
590	.globl theLastJump
591theLastJump:
592	mov	r9, r0
593	ldr	r3, =0xfff00000
594	ldr	r4, _TEXT_PHY_BASE
595	adr	r5, phy_last_jump
596	bic	r5, r5, r3
597	orr	r5, r5, r4
598	mov	pc, r5
599phy_last_jump:
600	/*
601	 * disable MMU stuff
602	 */
603	mrc	p15, 0, r0, c1, c0, 0
604	bic	r0, r0, #0x00002300	/* clear bits 13, 9:8 (--V- --RS) */
605	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
606	orr	r0, r0, #0x00000002	/* set bit 2 (A) Align */
607	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
608	mcr	p15, 0, r0, c1, c0, 0
609
610	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
611
612	mov	r0, #0
613	mov	pc, r9
614#endif
615
616
617/*
618 *************************************************************************
619 *
620 * Interrupt handling
621 *
622 *************************************************************************
623 */
624@
625@ IRQ stack frame.
626@
627#define S_FRAME_SIZE	72
628
629#define S_OLD_R0	68
630#define S_PSR		64
631#define S_PC		60
632#define S_LR		56
633#define S_SP		52
634
635#define S_IP		48
636#define S_FP		44
637#define S_R10		40
638#define S_R9		36
639#define S_R8		32
640#define S_R7		28
641#define S_R6		24
642#define S_R5		20
643#define S_R4		16
644#define S_R3		12
645#define S_R2		8
646#define S_R1		4
647#define S_R0		0
648
649#define MODE_SVC 0x13
650#define I_BIT	 0x80
651
652/*
653 * use bad_save_user_regs for abort/prefetch/undef/swi ...
654 */
655
656	.macro	bad_save_user_regs
657	/* carve out a frame on current user stack */
658	sub	sp, sp, #S_FRAME_SIZE
659	/* Save user registers (now in svc mode) r0-r12 */
660	stmia	sp, {r0 - r12}
661
662#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
663	ldr	r2, _armboot_start
664	sub	r2, r2, #(CONFIG_SYS_MALLOC_LEN)
665	/* set base 2 words into abort stack */
666	sub	r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8)
667#else
668	ldr	r2, IRQ_STACK_START_IN
669#endif
670	/* get values for "aborted" pc and cpsr (into parm regs) */
671	ldmia	r2, {r2 - r3}
672	/* grab pointer to old stack */
673	add	r0, sp, #S_FRAME_SIZE
674
675	add	r5, sp, #S_SP
676	mov	r1, lr
677	/* save sp_SVC, lr_SVC, pc, cpsr */
678	stmia	r5, {r0 - r3}
679	/* save current stack into r0 (param register) */
680	mov	r0, sp
681	.endm
682
683	.macro get_bad_stack
684#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
685	/* setup our mode stack (enter in banked mode) */
686	ldr	r13, _armboot_start
687	/* move past malloc pool */
688	sub	r13, r13, #(CONFIG_SYS_MALLOC_LEN)
689	/* move to reserved a couple spots for abort stack */
690	sub	r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
691#else
692	ldr	r13, IRQ_STACK_START_IN		@ setup our mode stack
693#endif
694
695	/* save caller lr in position 0 of saved stack */
696	str	lr, [r13]
697	/* get the spsr */
698	mrs	lr, spsr
699	/* save spsr in position 1 of saved stack */
700	str	lr, [r13, #4]
701
702	/* prepare SVC-Mode */
703	mov	r13, #MODE_SVC
704	@ msr	spsr_c, r13
705	/* switch modes, make sure moves will execute */
706	msr	spsr, r13
707	/* capture return pc */
708	mov	lr, pc
709	/* jump to next instruction & switch modes. */
710	movs	pc, lr
711	.endm
712
713	.macro get_bad_stack_swi
714	/* space on current stack for scratch reg. */
715	sub	r13, r13, #4
716	/* save R0's value. */
717	str	r0, [r13]
718#if defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
719	/* get data regions start */
720	ldr	r0, _armboot_start
721	/* move past malloc pool */
722	sub	r0, r0, #(CONFIG_SYS_MALLOC_LEN)
723	/* move past gbl and a couple spots for abort stack */
724	sub	r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
725#else
726	ldr	r13, IRQ_STACK_START_IN		@ setup our mode stack
727#endif
728	/* save caller lr in position 0 of saved stack */
729	str	lr, [r0]
730	/* get the spsr */
731	mrs	r0, spsr
732	/* save spsr in position 1 of saved stack */
733	str	lr, [r0, #4]
734	/* restore r0 */
735	ldr	r0, [r13]
736	/* pop stack entry */
737	add	r13, r13, #4
738	.endm
739
740/*
741 * exception handlers
742 */
743	.align	5
744undefined_instruction:
745	get_bad_stack
746	bad_save_user_regs
747	bl	do_undefined_instruction
748
749	.align	5
750software_interrupt:
751	get_bad_stack_swi
752	bad_save_user_regs
753	bl	do_software_interrupt
754
755	.align	5
756prefetch_abort:
757	get_bad_stack
758	bad_save_user_regs
759	bl	do_prefetch_abort
760
761	.align	5
762data_abort:
763	get_bad_stack
764	bad_save_user_regs
765	bl	do_data_abort
766
767	.align	5
768not_used:
769	get_bad_stack
770	bad_save_user_regs
771	bl	do_not_used
772
773	.align	5
774irq:
775	get_bad_stack
776	bad_save_user_regs
777	bl	do_irq
778
779	.align	5
780fiq:
781	get_bad_stack
782	bad_save_user_regs
783	bl	do_fiq
784#endif /* CONFIG_NAND_SPL */
785