xref: /rk3399_rockchip-uboot/arch/arm/cpu/arm1136/start.S (revision 959eaa74b83e4d18be5829a5a7c8deaa11aac7e0)
1/*
2 *  armboot - Startup Code for OMP2420/ARM1136 CPU-core
3 *
4 *  Copyright (c) 2004	Texas Instruments <r-woodruff2@ti.com>
5 *
6 *  Copyright (c) 2001	Marius Gröger <mag@sysgo.de>
7 *  Copyright (c) 2002	Alex Züpke <azu@sysgo.de>
8 *  Copyright (c) 2002	Gary Jennejohn <garyj@denx.de>
9 *  Copyright (c) 2003	Richard Woodruff <r-woodruff2@ti.com>
10 *  Copyright (c) 2003	Kshitij <kshitij@ti.com>
11 *
12 * See file CREDITS for list of people who contributed to this
13 * project.
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation; either version 2 of
18 * the License, or (at your option) any later version.
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
28 * MA 02111-1307 USA
29 */
30
31#include <asm-offsets.h>
32#include <config.h>
33#include <version.h>
34.globl _start
35_start: b	reset
36#ifdef CONFIG_SPL_BUILD
37	ldr	pc, _hang
38	ldr	pc, _hang
39	ldr	pc, _hang
40	ldr	pc, _hang
41	ldr	pc, _hang
42	ldr	pc, _hang
43	ldr	pc, _hang
44
45_hang:
46	.word	do_hang
47	.word	0x12345678
48	.word	0x12345678
49	.word	0x12345678
50	.word	0x12345678
51	.word	0x12345678
52	.word	0x12345678
53	.word	0x12345678	/* now 16*4=64 */
54#else
55	ldr	pc, _undefined_instruction
56	ldr	pc, _software_interrupt
57	ldr	pc, _prefetch_abort
58	ldr	pc, _data_abort
59	ldr	pc, _not_used
60	ldr	pc, _irq
61	ldr	pc, _fiq
62
63_undefined_instruction: .word undefined_instruction
64_software_interrupt:	.word software_interrupt
65_prefetch_abort:	.word prefetch_abort
66_data_abort:		.word data_abort
67_not_used:		.word not_used
68_irq:			.word irq
69_fiq:			.word fiq
70_pad:			.word 0x12345678 /* now 16*4=64 */
71#endif	/* CONFIG_SPL_BUILD */
72.global _end_vect
73_end_vect:
74
75	.balignl 16,0xdeadbeef
76/*
77 *************************************************************************
78 *
79 * Startup Code (reset vector)
80 *
81 * do important init only if we don't start from memory!
82 * setup Memory and board specific bits prior to relocation.
83 * relocate armboot to ram
84 * setup stack
85 *
86 *************************************************************************
87 */
88
89.globl _TEXT_BASE
90_TEXT_BASE:
91#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE)
92	.word	CONFIG_SPL_TEXT_BASE
93#else
94	.word	CONFIG_SYS_TEXT_BASE
95#endif
96
97/*
98 * These are defined in the board-specific linker script.
99 * Subtracting _start from them lets the linker put their
100 * relative position in the executable instead of leaving
101 * them null.
102 */
103.globl _bss_start_ofs
104_bss_start_ofs:
105	.word __bss_start - _start
106
107.global	_image_copy_end_ofs
108_image_copy_end_ofs:
109	.word 	__image_copy_end - _start
110
111.globl _bss_end_ofs
112_bss_end_ofs:
113	.word __bss_end - _start
114
115.globl _end_ofs
116_end_ofs:
117	.word _end - _start
118
119#ifdef CONFIG_USE_IRQ
120/* IRQ stack memory (calculated at run-time) */
121.globl IRQ_STACK_START
122IRQ_STACK_START:
123	.word	0x0badc0de
124
125/* IRQ stack memory (calculated at run-time) */
126.globl FIQ_STACK_START
127FIQ_STACK_START:
128	.word 0x0badc0de
129#endif
130
131/* IRQ stack memory (calculated at run-time) + 8 bytes */
132.globl IRQ_STACK_START_IN
133IRQ_STACK_START_IN:
134	.word	0x0badc0de
135
136/*
137 * the actual reset code
138 */
139
140reset:
141	/*
142	 * set the cpu to SVC32 mode
143	 */
144	mrs	r0,cpsr
145	bic	r0,r0,#0x1f
146	orr	r0,r0,#0xd3
147	msr	cpsr,r0
148
149#ifdef CONFIG_OMAP2420H4
150       /* Copy vectors to mask ROM indirect addr */
151	adr	r0, _start		/* r0 <- current position of code   */
152		add     r0, r0, #4				/* skip reset vector			*/
153	mov	r2, #64			/* r2 <- size to copy  */
154	add	r2, r0, r2		/* r2 <- source end address	    */
155	mov	r1, #SRAM_OFFSET0	  /* build vect addr */
156	mov	r3, #SRAM_OFFSET1
157	add	r1, r1, r3
158	mov	r3, #SRAM_OFFSET2
159	add	r1, r1, r3
160next:
161	ldmia	r0!, {r3-r10}		/* copy from source address [r0]    */
162	stmia	r1!, {r3-r10}		/* copy to   target address [r1]    */
163	cmp	r0, r2			/* until source end address [r2]    */
164	bne	next			/* loop until equal */
165	bl	cpy_clk_code		/* put dpll adjust code behind vectors */
166#endif
167	/* the mask ROM code should have PLL and others stable */
168#ifndef CONFIG_SKIP_LOWLEVEL_INIT
169	bl  cpu_init_crit
170#endif
171
172	bl	_main
173
174/*------------------------------------------------------------------------------*/
175
176/*
177 * void relocate_code (addr_sp, gd, addr_moni)
178 *
179 * This function relocates the monitor code.
180 */
181	.globl	relocate_code
182relocate_code:
183	mov	r4, r0	/* save addr_sp */
184	mov	r5, r1	/* save addr of gd */
185	mov	r6, r2	/* save addr of destination */
186
187	adr	r0, _start
188	cmp	r0, r6
189	moveq	r9, #0		/* no relocation. relocation offset(r9) = 0 */
190	beq	relocate_done		/* skip relocation */
191	mov	r1, r6			/* r1 <- scratch for copy_loop */
192	ldr	r3, _image_copy_end_ofs
193	add	r2, r0, r3		/* r2 <- source end address	    */
194
195copy_loop:
196	ldmia	r0!, {r9-r10}		/* copy from source address [r0]    */
197	stmia	r1!, {r9-r10}		/* copy to   target address [r1]    */
198	cmp	r0, r2			/* until source end address [r2]    */
199	blo	copy_loop
200
201#ifndef CONFIG_SPL_BUILD
202	/*
203	 * fix .rel.dyn relocations
204	 */
205	ldr	r0, _TEXT_BASE		/* r0 <- Text base */
206	sub	r9, r6, r0		/* r9 <- relocation offset */
207	ldr	r10, _dynsym_start_ofs	/* r10 <- sym table ofs */
208	add	r10, r10, r0		/* r10 <- sym table in FLASH */
209	ldr	r2, _rel_dyn_start_ofs	/* r2 <- rel dyn start ofs */
210	add	r2, r2, r0		/* r2 <- rel dyn start in FLASH */
211	ldr	r3, _rel_dyn_end_ofs	/* r3 <- rel dyn end ofs */
212	add	r3, r3, r0		/* r3 <- rel dyn end in FLASH */
213fixloop:
214	ldr	r0, [r2]		/* r0 <- location to fix up, IN FLASH! */
215	add	r0, r0, r9		/* r0 <- location to fix up in RAM */
216	ldr	r1, [r2, #4]
217	and	r7, r1, #0xff
218	cmp	r7, #23			/* relative fixup? */
219	beq	fixrel
220	cmp	r7, #2			/* absolute fixup? */
221	beq	fixabs
222	/* ignore unknown type of fixup */
223	b	fixnext
224fixabs:
225	/* absolute fix: set location to (offset) symbol value */
226	mov	r1, r1, LSR #4		/* r1 <- symbol index in .dynsym */
227	add	r1, r10, r1		/* r1 <- address of symbol in table */
228	ldr	r1, [r1, #4]		/* r1 <- symbol value */
229	add	r1, r1, r9		/* r1 <- relocated sym addr */
230	b	fixnext
231fixrel:
232	/* relative fix: increase location by offset */
233	ldr	r1, [r0]
234	add	r1, r1, r9
235fixnext:
236	str	r1, [r0]
237	add	r2, r2, #8		/* each rel.dyn entry is 8 bytes */
238	cmp	r2, r3
239	blo	fixloop
240	bx	lr
241
242#endif
243
244relocate_done:
245
246	bx	lr
247
248#ifndef CONFIG_SPL_BUILD
249
250_rel_dyn_start_ofs:
251	.word __rel_dyn_start - _start
252_rel_dyn_end_ofs:
253	.word __rel_dyn_end - _start
254_dynsym_start_ofs:
255	.word __dynsym_start - _start
256
257#endif
258
259	.globl	c_runtime_cpu_setup
260c_runtime_cpu_setup:
261
262	bx	lr
263
264/*
265 *************************************************************************
266 *
267 * CPU_init_critical registers
268 *
269 * setup important registers
270 * setup memory timing
271 *
272 *************************************************************************
273 */
274#ifndef CONFIG_SKIP_LOWLEVEL_INIT
275cpu_init_crit:
276	/*
277	 * flush v4 I/D caches
278	 */
279	mov	r0, #0
280	mcr	p15, 0, r0, c7, c7, 0	/* Invalidate I+D+BTB caches */
281	mcr	p15, 0, r0, c8, c7, 0	/* Invalidate Unified TLB */
282
283	/*
284	 * disable MMU stuff and caches
285	 */
286	mrc	p15, 0, r0, c1, c0, 0
287	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
288	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
289	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
290	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
291	mcr	p15, 0, r0, c1, c0, 0
292
293	/*
294	 * Jump to board specific initialization... The Mask ROM will have already initialized
295	 * basic memory.  Go here to bump up clock rate and handle wake up conditions.
296	 */
297	mov	ip, lr		/* persevere link reg across call */
298	bl	lowlevel_init	/* go setup pll,mux,memory */
299	mov	lr, ip		/* restore link */
300	mov	pc, lr		/* back to my caller */
301#endif /* CONFIG_SKIP_LOWLEVEL_INIT */
302
303#ifndef CONFIG_SPL_BUILD
304/*
305 *************************************************************************
306 *
307 * Interrupt handling
308 *
309 *************************************************************************
310 */
311@
312@ IRQ stack frame.
313@
314#define S_FRAME_SIZE	72
315
316#define S_OLD_R0	68
317#define S_PSR		64
318#define S_PC		60
319#define S_LR		56
320#define S_SP		52
321
322#define S_IP		48
323#define S_FP		44
324#define S_R10		40
325#define S_R9		36
326#define S_R8		32
327#define S_R7		28
328#define S_R6		24
329#define S_R5		20
330#define S_R4		16
331#define S_R3		12
332#define S_R2		8
333#define S_R1		4
334#define S_R0		0
335
336#define MODE_SVC 0x13
337#define I_BIT	 0x80
338
339/*
340 * use bad_save_user_regs for abort/prefetch/undef/swi ...
341 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
342 */
343
344	.macro	bad_save_user_regs
345	sub	sp, sp, #S_FRAME_SIZE		@ carve out a frame on current user stack
346	stmia	sp, {r0 - r12}			@ Save user registers (now in svc mode) r0-r12
347
348	ldr	r2, IRQ_STACK_START_IN		@ set base 2 words into abort stack
349	ldmia	r2, {r2 - r3}			@ get values for "aborted" pc and cpsr (into parm regs)
350	add	r0, sp, #S_FRAME_SIZE		@ grab pointer to old stack
351
352	add	r5, sp, #S_SP
353	mov	r1, lr
354	stmia	r5, {r0 - r3}			@ save sp_SVC, lr_SVC, pc, cpsr
355	mov	r0, sp				@ save current stack into r0 (param register)
356	.endm
357
358	.macro	irq_save_user_regs
359	sub	sp, sp, #S_FRAME_SIZE
360	stmia	sp, {r0 - r12}			@ Calling r0-r12
361	add	r8, sp, #S_PC			@ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good.
362	stmdb	r8, {sp, lr}^			@ Calling SP, LR
363	str	lr, [r8, #0]			@ Save calling PC
364	mrs	r6, spsr
365	str	r6, [r8, #4]			@ Save CPSR
366	str	r0, [r8, #8]			@ Save OLD_R0
367	mov	r0, sp
368	.endm
369
370	.macro	irq_restore_user_regs
371	ldmia	sp, {r0 - lr}^			@ Calling r0 - lr
372	mov	r0, r0
373	ldr	lr, [sp, #S_PC]			@ Get PC
374	add	sp, sp, #S_FRAME_SIZE
375	subs	pc, lr, #4			@ return & move spsr_svc into cpsr
376	.endm
377
378	.macro get_bad_stack
379	ldr	r13, IRQ_STACK_START_IN		@ setup our mode stack (enter in banked mode)
380
381	str	lr, [r13]			@ save caller lr in position 0 of saved stack
382	mrs	lr, spsr			@ get the spsr
383	str	lr, [r13, #4]			@ save spsr in position 1 of saved stack
384
385	mov	r13, #MODE_SVC			@ prepare SVC-Mode
386	@ msr	spsr_c, r13
387	msr	spsr, r13			@ switch modes, make sure moves will execute
388	mov	lr, pc				@ capture return pc
389	movs	pc, lr				@ jump to next instruction & switch modes.
390	.endm
391
392	.macro get_bad_stack_swi
393	sub	r13, r13, #4			@ space on current stack for scratch reg.
394	str	r0, [r13]			@ save R0's value.
395	ldr	r0, IRQ_STACK_START_IN		@ get data regions start
396	str	lr, [r0]			@ save caller lr in position 0 of saved stack
397	mrs	r0, spsr			@ get the spsr
398	str	lr, [r0, #4]			@ save spsr in position 1 of saved stack
399	ldr	r0, [r13]			@ restore r0
400	add	r13, r13, #4			@ pop stack entry
401	.endm
402
403	.macro get_irq_stack			@ setup IRQ stack
404	ldr	sp, IRQ_STACK_START
405	.endm
406
407	.macro get_fiq_stack			@ setup FIQ stack
408	ldr	sp, FIQ_STACK_START
409	.endm
410#endif	/* CONFIG_SPL_BUILD */
411
412/*
413 * exception handlers
414 */
415#ifdef CONFIG_SPL_BUILD
416	.align	5
417do_hang:
418	ldr	sp, _TEXT_BASE			/* use 32 words about stack */
419	bl	hang				/* hang and never return */
420#else	/* !CONFIG_SPL_BUILD */
421	.align	5
422undefined_instruction:
423	get_bad_stack
424	bad_save_user_regs
425	bl	do_undefined_instruction
426
427	.align	5
428software_interrupt:
429	get_bad_stack_swi
430	bad_save_user_regs
431	bl	do_software_interrupt
432
433	.align	5
434prefetch_abort:
435	get_bad_stack
436	bad_save_user_regs
437	bl	do_prefetch_abort
438
439	.align	5
440data_abort:
441	get_bad_stack
442	bad_save_user_regs
443	bl	do_data_abort
444
445	.align	5
446not_used:
447	get_bad_stack
448	bad_save_user_regs
449	bl	do_not_used
450
451#ifdef CONFIG_USE_IRQ
452
453	.align	5
454irq:
455	get_irq_stack
456	irq_save_user_regs
457	bl	do_irq
458	irq_restore_user_regs
459
460	.align	5
461fiq:
462	get_fiq_stack
463	/* someone ought to write a more effiction fiq_save_user_regs */
464	irq_save_user_regs
465	bl	do_fiq
466	irq_restore_user_regs
467
468#else
469
470	.align	5
471irq:
472	get_bad_stack
473	bad_save_user_regs
474	bl	do_irq
475
476	.align	5
477fiq:
478	get_bad_stack
479	bad_save_user_regs
480	bl	do_fiq
481
482#endif
483	.align 5
484.global arm1136_cache_flush
485arm1136_cache_flush:
486#if !defined(CONFIG_SYS_ICACHE_OFF)
487		mcr	p15, 0, r1, c7, c5, 0	@ invalidate I cache
488#endif
489#if !defined(CONFIG_SYS_DCACHE_OFF)
490		mcr	p15, 0, r1, c7, c14, 0	@ invalidate D cache
491#endif
492		mov	pc, lr			@ back to caller
493#endif	/* CONFIG_SPL_BUILD */
494