summaryrefslogtreecommitdiff
path: root/arch/arm/cpu/arm1176/start.S
blob: a540edbfbf807bc008b4bd8b576510692b524d98 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
/*
 *  armboot - Startup Code for ARM1176 CPU-core
 *
 * Copyright (c) 2007	Samsung Electronics
 *
 * Copyright (C) 2008
 * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 * 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
 * 2007-09-21 - Added MoviNAND and OneNAND boot codes by
 * jsgood (jsgood.yang@samsung.com)
 * Base codes by scsuh (sc.suh)
 */

#include <config.h>
#include <version.h>
#ifdef CONFIG_ENABLE_MMU
#include <asm/proc/domain.h>
#endif

#if !defined(CONFIG_ENABLE_MMU) && !defined(CONFIG_SYS_PHY_UBOOT_BASE)
#define CONFIG_SYS_PHY_UBOOT_BASE	CONFIG_SYS_UBOOT_BASE
#endif

/*
 *************************************************************************
 *
 * Jump vector table as in table 3.1 in [1]
 *
 *************************************************************************
 */

.globl _start
_start: b	reset
#ifndef CONFIG_NAND_SPL
	ldr	pc, _undefined_instruction
	ldr	pc, _software_interrupt
	ldr	pc, _prefetch_abort
	ldr	pc, _data_abort
	ldr	pc, _not_used
	ldr	pc, _irq
	ldr	pc, _fiq

_undefined_instruction:
	.word undefined_instruction
_software_interrupt:
	.word software_interrupt
_prefetch_abort:
	.word prefetch_abort
_data_abort:
	.word data_abort
_not_used:
	.word not_used
_irq:
	.word irq
_fiq:
	.word fiq
_pad:
	.word 0x12345678 /* now 16*4=64 */
#else
	. = _start + 64
#endif

.global _end_vect
_end_vect:
	.balignl 16,0xdeadbeef
/*
 *************************************************************************
 *
 * Startup Code (reset vector)
 *
 * do important init only if we don't start from memory!
 * setup Memory and board specific bits prior to relocation.
 * relocate armboot to ram
 * setup stack
 *
 *************************************************************************
 */

_TEXT_BASE:
	.word	TEXT_BASE

/*
 * Below variable is very important because we use MMU in U-Boot.
 * Without it, we cannot run code correctly before MMU is ON.
 * by scsuh.
 */
_TEXT_PHY_BASE:
	.word	CONFIG_SYS_PHY_UBOOT_BASE

.globl _armboot_start
_armboot_start:
	.word _start

/*
 * These are defined in the board-specific linker script.
 */
.globl _bss_start
_bss_start:
	.word __bss_start

.globl _bss_end
_bss_end:
	.word _end

/*
 * the actual reset code
 */

reset:
	/*
	 * set the cpu to SVC32 mode
	 */
	mrs	r0, cpsr
	bic	r0, r0, #0x3f
	orr	r0, r0, #0xd3
	msr	cpsr, r0

/*
 *************************************************************************
 *
 * CPU_init_critical registers
 *
 * setup important registers
 * setup memory timing
 *
 *************************************************************************
 */
	/*
	 * we do sys-critical inits only at reboot,
	 * not when booting from ram!
	 */
cpu_init_crit:
	/*
	 * When booting from NAND - it has definitely been a reset, so, no need
	 * to flush caches and disable the MMU
	 */
#ifndef CONFIG_NAND_SPL
	/*
	 * flush v4 I/D caches
	 */
	mov	r0, #0
	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */

	/*
	 * disable MMU stuff and caches
	 */
	mrc	p15, 0, r0, c1, c0, 0
	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache

	/* Prepare to disable the MMU */
	adr	r2, mmu_disable_phys
	sub	r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - TEXT_BASE)
	b	mmu_disable

	.align 5
	/* Run in a single cache-line */
mmu_disable:
	mcr	p15, 0, r0, c1, c0, 0
	nop
	nop
	mov	pc, r2
mmu_disable_phys:

#ifdef CONFIG_DISABLE_TCM
	/*
	 * Disable the TCMs
	 */
	mrc	p15, 0, r0, c0, c0, 2	/* Return TCM details */
	cmp	r0, #0
	beq	skip_tcmdisable
	mov	r1, #0
	mov	r2, #1
	tst	r0, r2
	mcrne	p15, 0, r1, c9, c1, 1	/* Disable Instruction TCM if present*/
	tst	r0, r2, LSL #16
	mcrne	p15, 0, r1, c9, c1, 0	/* Disable Data TCM if present*/
skip_tcmdisable:
#endif
#endif

#ifdef CONFIG_PERIPORT_REMAP
	/* Peri port setup */
	ldr	r0, =CONFIG_PERIPORT_BASE
	orr	r0, r0, #CONFIG_PERIPORT_SIZE
	mcr	p15,0,r0,c15,c2,4
#endif

	/*
	 * Go setup Memory and board specific bits prior to relocation.
	 */
	bl	lowlevel_init		/* go setup pll,mux,memory */

#ifndef CONFIG_SKIP_RELOCATE_UBOOT
relocate:				/* relocate U-Boot to RAM	    */
	adr	r0, _start		/* r0 <- current position of code   */
	ldr	r1, _TEXT_BASE		/* test if we run from flash or RAM */
	cmp     r0, r1                  /* don't reloc during debug         */
	beq     stack_setup

	ldr	r2, _armboot_start
	ldr	r3, _bss_start
	sub	r2, r3, r2		/* r2 <- size of armboot            */
	add	r2, r0, r2		/* r2 <- source end address         */

copy_loop:
	ldmia	r0!, {r3-r10}		/* copy from source address [r0]    */
	stmia	r1!, {r3-r10}		/* copy to   target address [r1]    */
	cmp	r0, r2			/* until source end addreee [r2]    */
	ble	copy_loop
#endif	/* CONFIG_SKIP_RELOCATE_UBOOT */

#ifdef CONFIG_ENABLE_MMU
enable_mmu:
	/* enable domain access */
	ldr	r5, =0x0000ffff
	mcr	p15, 0, r5, c3, c0, 0	/* load domain access register */

	/* Set the TTB register */
	ldr	r0, _mmu_table_base
	ldr	r1, =CONFIG_SYS_PHY_UBOOT_BASE
	ldr	r2, =0xfff00000
	bic	r0, r0, r2
	orr	r1, r0, r1
	mcr	p15, 0, r1, c2, c0, 0

	/* Enable the MMU */
	mrc	p15, 0, r0, c1, c0, 0
	orr	r0, r0, #1		/* Set CR_M to enable MMU */

	/* Prepare to enable the MMU */
	adr	r1, skip_hw_init
	and	r1, r1, #0x3fc
	ldr	r2, _TEXT_BASE
	ldr	r3, =0xfff00000
	and	r2, r2, r3
	orr	r2, r2, r1
	b	mmu_enable

	.align 5
	/* Run in a single cache-line */
mmu_enable:

	mcr	p15, 0, r0, c1, c0, 0
	nop
	nop
	mov	pc, r2
skip_hw_init:
#endif

	/* Set up the stack						    */
stack_setup:
	ldr	r0, =CONFIG_SYS_UBOOT_BASE	/* base of copy in DRAM	    */
	sub	r0, r0, #CONFIG_SYS_MALLOC_LEN	/* malloc area                      */
	sub	r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo                        */
	sub	sp, r0, #12		/* leave 3 words for abort-stack    */

clear_bss:
	ldr	r0, _bss_start		/* find start of bss segment        */
	ldr	r1, _bss_end		/* stop here                        */
	mov 	r2, #0			/* clear                            */

clbss_l:
	str	r2, [r0]		/* clear loop...                    */
	add	r0, r0, #4
	cmp	r0, r1
	ble	clbss_l

#ifndef CONFIG_NAND_SPL
	ldr	pc, _start_armboot

_start_armboot:
	.word start_armboot
#else
	b	nand_boot
/*	.word nand_boot*/
#endif

#ifdef CONFIG_ENABLE_MMU
_mmu_table_base:
	.word mmu_table
#endif

#ifndef CONFIG_NAND_SPL
/*
 * we assume that cache operation is done before. (eg. cleanup_before_linux())
 * actually, we don't need to do anything about cache if not use d-cache in
 * U-Boot. So, in this function we clean only MMU. by scsuh
 *
 * void	theLastJump(void *kernel, int arch_num, uint boot_params);
 */
#ifdef CONFIG_ENABLE_MMU
	.globl theLastJump
theLastJump:
	mov	r9, r0
	ldr	r3, =0xfff00000
	ldr	r4, _TEXT_PHY_BASE
	adr	r5, phy_last_jump
	bic	r5, r5, r3
	orr	r5, r5, r4
	mov	pc, r5
phy_last_jump:
	/*
	 * disable MMU stuff
	 */
	mrc	p15, 0, r0, c1, c0, 0
	bic	r0, r0, #0x00002300	/* clear bits 13, 9:8 (--V- --RS) */
	bic	r0, r0, #0x00000087	/* clear bits 7, 2:0 (B--- -CAM) */
	orr	r0, r0, #0x00000002	/* set bit 2 (A) Align */
	orr	r0, r0, #0x00001000	/* set bit 12 (I) I-Cache */
	mcr	p15, 0, r0, c1, c0, 0

	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */

	mov	r0, #0
	mov	pc, r9
#endif


/*
 *************************************************************************
 *
 * Interrupt handling
 *
 *************************************************************************
 */
@
@ IRQ stack frame.
@
#define S_FRAME_SIZE	72

#define S_OLD_R0	68
#define S_PSR		64
#define S_PC		60
#define S_LR		56
#define S_SP		52

#define S_IP		48
#define S_FP		44
#define S_R10		40
#define S_R9		36
#define S_R8		32
#define S_R7		28
#define S_R6		24
#define S_R5		20
#define S_R4		16
#define S_R3		12
#define S_R2		8
#define S_R1		4
#define S_R0		0

#define MODE_SVC 0x13
#define I_BIT	 0x80

/*
 * use bad_save_user_regs for abort/prefetch/undef/swi ...
 */

	.macro	bad_save_user_regs
	/* carve out a frame on current user stack */
	sub	sp, sp, #S_FRAME_SIZE
	/* Save user registers (now in svc mode) r0-r12 */
	stmia	sp, {r0 - r12}

	ldr	r2, _armboot_start
	sub	r2, r2, #(CONFIG_SYS_MALLOC_LEN)
	/* set base 2 words into abort stack */
	sub	r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8)
	/* get values for "aborted" pc and cpsr (into parm regs) */
	ldmia	r2, {r2 - r3}
	/* grab pointer to old stack */
	add	r0, sp, #S_FRAME_SIZE

	add	r5, sp, #S_SP
	mov	r1, lr
	/* save sp_SVC, lr_SVC, pc, cpsr */
	stmia	r5, {r0 - r3}
	/* save current stack into r0 (param register) */
	mov	r0, sp
	.endm

	.macro get_bad_stack
	/* setup our mode stack (enter in banked mode) */
	ldr	r13, _armboot_start
	/* move past malloc pool */
	sub	r13, r13, #(CONFIG_SYS_MALLOC_LEN)
	/* move to reserved a couple spots for abort stack */
	sub	r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8)

	/* save caller lr in position 0 of saved stack */
	str	lr, [r13]
	/* get the spsr */
	mrs	lr, spsr
	/* save spsr in position 1 of saved stack */
	str	lr, [r13, #4]

	/* prepare SVC-Mode */
	mov	r13, #MODE_SVC
	@ msr	spsr_c, r13
	/* switch modes, make sure moves will execute */
	msr	spsr, r13
	/* capture return pc */
	mov	lr, pc
	/* jump to next instruction & switch modes. */
	movs	pc, lr
	.endm

	.macro get_bad_stack_swi
	/* space on current stack for scratch reg. */
	sub	r13, r13, #4
	/* save R0's value. */
	str	r0, [r13]
	/* get data regions start */
	ldr	r0, _armboot_start
	/* move past malloc pool */
	sub	r0, r0, #(CONFIG_SYS_MALLOC_LEN)
	/* move past gbl and a couple spots for abort stack */
	sub	r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
	/* save caller lr in position 0 of saved stack */
	str	lr, [r0]
	/* get the spsr */
	mrs	r0, spsr
	/* save spsr in position 1 of saved stack */
	str	lr, [r0, #4]
	/* restore r0 */
	ldr	r0, [r13]
	/* pop stack entry */
	add	r13, r13, #4
	.endm

/*
 * exception handlers
 */
	.align	5
undefined_instruction:
	get_bad_stack
	bad_save_user_regs
	bl	do_undefined_instruction

	.align	5
software_interrupt:
	get_bad_stack_swi
	bad_save_user_regs
	bl	do_software_interrupt

	.align	5
prefetch_abort:
	get_bad_stack
	bad_save_user_regs
	bl	do_prefetch_abort

	.align	5
data_abort:
	get_bad_stack
	bad_save_user_regs
	bl	do_data_abort

	.align	5
not_used:
	get_bad_stack
	bad_save_user_regs
	bl	do_not_used

	.align	5
irq:
	get_bad_stack
	bad_save_user_regs
	bl	do_irq

	.align	5
fiq:
	get_bad_stack
	bad_save_user_regs
	bl	do_fiq
#endif /* CONFIG_NAND_SPL */