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arm: Remove unused relocate_code() parameters
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1/*
2 * armboot - Startup Code for ARM920 CPU-core
3 *
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4 * Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
5 * Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
792a09eb 6 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
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7 *
8 * See file CREDITS for list of people who contributed to this
9 * project.
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation; either version 2 of
14 * the License, or (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24 * MA 02111-1307 USA
25 */
26
25ddd1fb 27#include <asm-offsets.h>
9689ddcc 28#include <common.h>
fe8c2806 29#include <config.h>
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30
31/*
32 *************************************************************************
33 *
34 * Jump vector table as in table 3.1 in [1]
35 *
36 *************************************************************************
37 */
38
39
40.globl _start
d67cce2d 41_start: b start_code
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42 ldr pc, _undefined_instruction
43 ldr pc, _software_interrupt
44 ldr pc, _prefetch_abort
45 ldr pc, _data_abort
46 ldr pc, _not_used
47 ldr pc, _irq
48 ldr pc, _fiq
49
50_undefined_instruction: .word undefined_instruction
51_software_interrupt: .word software_interrupt
52_prefetch_abort: .word prefetch_abort
53_data_abort: .word data_abort
54_not_used: .word not_used
55_irq: .word irq
56_fiq: .word fiq
57
58 .balignl 16,0xdeadbeef
59
60
61/*
62 *************************************************************************
63 *
80767a6c 64 * Startup Code (called from the ARM reset exception vector)
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65 *
66 * do important init only if we don't start from memory!
67 * relocate armboot to ram
68 * setup stack
69 * jump to second stage
70 *
71 *************************************************************************
72 */
73
cc7cdcbd 74.globl _TEXT_BASE
fe8c2806 75_TEXT_BASE:
508611bc
BT
76#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE)
77 .word CONFIG_SPL_TEXT_BASE
78#else
14d0a02a 79 .word CONFIG_SYS_TEXT_BASE
508611bc 80#endif
fe8c2806 81
fe8c2806 82/*
f6e20fc6 83 * These are defined in the board-specific linker script.
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84 * Subtracting _start from them lets the linker put their
85 * relative position in the executable instead of leaving
86 * them null.
fe8c2806 87 */
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88.globl _bss_start_ofs
89_bss_start_ofs:
90 .word __bss_start - _start
f6e20fc6 91
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92.globl _image_copy_end_ofs
93_image_copy_end_ofs:
94 .word __image_copy_end - _start
95
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96.globl _bss_end_ofs
97_bss_end_ofs:
3929fb0a 98 .word __bss_end - _start
fe8c2806 99
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100.globl _end_ofs
101_end_ofs:
102 .word _end - _start
103
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104#ifdef CONFIG_USE_IRQ
105/* IRQ stack memory (calculated at run-time) */
106.globl IRQ_STACK_START
107IRQ_STACK_START:
108 .word 0x0badc0de
109
110/* IRQ stack memory (calculated at run-time) */
111.globl FIQ_STACK_START
112FIQ_STACK_START:
113 .word 0x0badc0de
114#endif
115
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116/* IRQ stack memory (calculated at run-time) + 8 bytes */
117.globl IRQ_STACK_START_IN
118IRQ_STACK_START_IN:
119 .word 0x0badc0de
120
fe8c2806 121/*
80767a6c 122 * the actual start code
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123 */
124
80767a6c 125start_code:
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126 /*
127 * set the cpu to SVC32 mode
128 */
d67cce2d 129 mrs r0, cpsr
130 bic r0, r0, #0x1f
131 orr r0, r0, #0xd3
132 msr cpsr, r0
80767a6c 133
ed3b18e0 134#if defined(CONFIG_AT91RM9200DK) || defined(CONFIG_AT91RM9200EK)
d4fc6012 135 /*
80767a6c 136 * relocate exception table
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137 */
138 ldr r0, =_start
139 ldr r1, =0x0
140 mov r2, #16
141copyex:
142 subs r2, r2, #1
143 ldr r3, [r0], #4
144 str r3, [r1], #4
145 bne copyex
146#endif
147
ac67804f 148#ifdef CONFIG_S3C24X0
80767a6c
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149 /* turn off the watchdog */
150
151# if defined(CONFIG_S3C2400)
d67cce2d 152# define pWTCON 0x15300000
16263087 153# define INTMSK 0x14400008 /* Interrupt-Controller base addresses */
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154# define CLKDIVN 0x14800014 /* clock divisor register */
155#else
d67cce2d 156# define pWTCON 0x53000000
16263087 157# define INTMSK 0x4A000008 /* Interrupt-Controller base addresses */
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158# define INTSUBMSK 0x4A00001C
159# define CLKDIVN 0x4C000014 /* clock divisor register */
160# endif
161
d67cce2d 162 ldr r0, =pWTCON
163 mov r1, #0x0
164 str r1, [r0]
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165
166 /*
167 * mask all IRQs by setting all bits in the INTMR - default
168 */
169 mov r1, #0xffffffff
170 ldr r0, =INTMSK
171 str r1, [r0]
281e00a3 172# if defined(CONFIG_S3C2410)
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173 ldr r1, =0x3ff
174 ldr r0, =INTSUBMSK
175 str r1, [r0]
281e00a3 176# endif
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177
178 /* FCLK:HCLK:PCLK = 1:2:4 */
179 /* default FCLK is 120 MHz ! */
180 ldr r0, =CLKDIVN
181 mov r1, #3
182 str r1, [r0]
ac67804f 183#endif /* CONFIG_S3C24X0 */
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184
185 /*
186 * we do sys-critical inits only at reboot,
187 * not when booting from ram!
188 */
8aa1a2d1 189#ifndef CONFIG_SKIP_LOWLEVEL_INIT
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190 bl cpu_init_crit
191#endif
192
e05e5de7 193 bl _main
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194
195/*------------------------------------------------------------------------------*/
196
197/*
5c6db120 198 * void relocate_code(addr_moni)
cc7cdcbd 199 *
959eaa74 200 * This function relocates the monitor code.
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201 */
202 .globl relocate_code
203relocate_code:
5c6db120 204 mov r6, r0 /* save addr of destination */
cc7cdcbd 205
cc7cdcbd 206 adr r0, _start
4b3db1cd 207 subs r9, r6, r0 /* r9 <- relocation offset */
e05e5de7 208 beq relocate_done /* skip relocation */
a78fb68f 209 mov r1, r6 /* r1 <- scratch for copy_loop */
7086e91b 210 ldr r3, _image_copy_end_ofs
3336ca60 211 add r2, r0, r3 /* r2 <- source end address */
cc7cdcbd 212
cc7cdcbd 213copy_loop:
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214 ldmia r0!, {r10-r11} /* copy from source address [r0] */
215 stmia r1!, {r10-r11} /* copy to target address [r1] */
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216 cmp r0, r2 /* until source end address [r2] */
217 blo copy_loop
cc7cdcbd 218
401bb30b 219#ifndef CONFIG_SPL_BUILD
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220 /*
221 * fix .rel.dyn relocations
222 */
223 ldr r0, _TEXT_BASE /* r0 <- Text base */
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224 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
225 add r10, r10, r0 /* r10 <- sym table in FLASH */
226 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
227 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
228 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
229 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
cc7cdcbd 230fixloop:
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231 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
232 add r0, r0, r9 /* r0 <- location to fix up in RAM */
233 ldr r1, [r2, #4]
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234 and r7, r1, #0xff
235 cmp r7, #23 /* relative fixup? */
3336ca60 236 beq fixrel
1f52d89f 237 cmp r7, #2 /* absolute fixup? */
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238 beq fixabs
239 /* ignore unknown type of fixup */
240 b fixnext
241fixabs:
242 /* absolute fix: set location to (offset) symbol value */
243 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
244 add r1, r10, r1 /* r1 <- address of symbol in table */
245 ldr r1, [r1, #4] /* r1 <- symbol value */
3600945b 246 add r1, r1, r9 /* r1 <- relocated sym addr */
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247 b fixnext
248fixrel:
249 /* relative fix: increase location by offset */
250 ldr r1, [r0]
251 add r1, r1, r9
252fixnext:
253 str r1, [r0]
254 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
cc7cdcbd 255 cmp r2, r3
79e63139 256 blo fixloop
cc7cdcbd 257#endif
cc7cdcbd 258
e05e5de7 259relocate_done:
cc7cdcbd 260
cc7cdcbd
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261 mov pc, lr
262
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263_rel_dyn_start_ofs:
264 .word __rel_dyn_start - _start
265_rel_dyn_end_ofs:
266 .word __rel_dyn_end - _start
267_dynsym_start_ofs:
268 .word __dynsym_start - _start
269
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270 .globl c_runtime_cpu_setup
271c_runtime_cpu_setup:
272
273 mov pc, lr
274
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275/*
276 *************************************************************************
277 *
278 * CPU_init_critical registers
279 *
280 * setup important registers
281 * setup memory timing
282 *
283 *************************************************************************
284 */
285
286
db28ddb4 287#ifndef CONFIG_SKIP_LOWLEVEL_INIT
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288cpu_init_crit:
289 /*
290 * flush v4 I/D caches
291 */
292 mov r0, #0
293 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
294 mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
295
296 /*
297 * disable MMU stuff and caches
298 */
299 mrc p15, 0, r0, c1, c0, 0
300 bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
301 bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
302 orr r0, r0, #0x00000002 @ set bit 2 (A) Align
303 orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
304 mcr p15, 0, r0, c1, c0, 0
305
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306 /*
307 * before relocating, we have to setup RAM timing
308 * because memory timing is board-dependend, you will
400558b5 309 * find a lowlevel_init.S in your board directory.
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310 */
311 mov ip, lr
d4fc6012 312
400558b5 313 bl lowlevel_init
cb82a532 314
fe8c2806 315 mov lr, ip
fe8c2806 316 mov pc, lr
db28ddb4 317#endif /* CONFIG_SKIP_LOWLEVEL_INIT */
fe8c2806 318
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319/*
320 *************************************************************************
321 *
322 * Interrupt handling
323 *
324 *************************************************************************
325 */
326
327@
328@ IRQ stack frame.
329@
330#define S_FRAME_SIZE 72
331
332#define S_OLD_R0 68
333#define S_PSR 64
334#define S_PC 60
335#define S_LR 56
336#define S_SP 52
337
338#define S_IP 48
339#define S_FP 44
340#define S_R10 40
341#define S_R9 36
342#define S_R8 32
343#define S_R7 28
344#define S_R6 24
345#define S_R5 20
346#define S_R4 16
347#define S_R3 12
348#define S_R2 8
349#define S_R1 4
350#define S_R0 0
351
d67cce2d 352#define MODE_SVC 0x13
353#define I_BIT 0x80
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354
355/*
356 * use bad_save_user_regs for abort/prefetch/undef/swi ...
357 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
358 */
359
360 .macro bad_save_user_regs
361 sub sp, sp, #S_FRAME_SIZE
362 stmia sp, {r0 - r12} @ Calling r0-r12
cc7cdcbd 363 ldr r2, IRQ_STACK_START_IN
f07771cc 364 ldmia r2, {r2 - r3} @ get pc, cpsr
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365 add r0, sp, #S_FRAME_SIZE @ restore sp_SVC
366
367 add r5, sp, #S_SP
368 mov r1, lr
f07771cc 369 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
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370 mov r0, sp
371 .endm
372
373 .macro irq_save_user_regs
374 sub sp, sp, #S_FRAME_SIZE
375 stmia sp, {r0 - r12} @ Calling r0-r12
d67cce2d 376 add r7, sp, #S_PC
377 stmdb r7, {sp, lr}^ @ Calling SP, LR
378 str lr, [r7, #0] @ Save calling PC
379 mrs r6, spsr
380 str r6, [r7, #4] @ Save CPSR
381 str r0, [r7, #8] @ Save OLD_R0
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382 mov r0, sp
383 .endm
384
385 .macro irq_restore_user_regs
386 ldmia sp, {r0 - lr}^ @ Calling r0 - lr
387 mov r0, r0
388 ldr lr, [sp, #S_PC] @ Get PC
389 add sp, sp, #S_FRAME_SIZE
d67cce2d 390 /* return & move spsr_svc into cpsr */
391 subs pc, lr, #4
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392 .endm
393
394 .macro get_bad_stack
cc7cdcbd 395 ldr r13, IRQ_STACK_START_IN @ setup our mode stack
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396
397 str lr, [r13] @ save caller lr / spsr
398 mrs lr, spsr
d67cce2d 399 str lr, [r13, #4]
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400
401 mov r13, #MODE_SVC @ prepare SVC-Mode
402 @ msr spsr_c, r13
403 msr spsr, r13
404 mov lr, pc
405 movs pc, lr
406 .endm
407
408 .macro get_irq_stack @ setup IRQ stack
409 ldr sp, IRQ_STACK_START
410 .endm
411
412 .macro get_fiq_stack @ setup FIQ stack
413 ldr sp, FIQ_STACK_START
414 .endm
415
416/*
417 * exception handlers
418 */
419 .align 5
420undefined_instruction:
421 get_bad_stack
422 bad_save_user_regs
53677ef1 423 bl do_undefined_instruction
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424
425 .align 5
426software_interrupt:
427 get_bad_stack
428 bad_save_user_regs
53677ef1 429 bl do_software_interrupt
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430
431 .align 5
432prefetch_abort:
433 get_bad_stack
434 bad_save_user_regs
53677ef1 435 bl do_prefetch_abort
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436
437 .align 5
438data_abort:
439 get_bad_stack
440 bad_save_user_regs
53677ef1 441 bl do_data_abort
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442
443 .align 5
444not_used:
445 get_bad_stack
446 bad_save_user_regs
53677ef1 447 bl do_not_used
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448
449#ifdef CONFIG_USE_IRQ
450
451 .align 5
452irq:
453 get_irq_stack
454 irq_save_user_regs
53677ef1 455 bl do_irq
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456 irq_restore_user_regs
457
458 .align 5
459fiq:
460 get_fiq_stack
461 /* someone ought to write a more effiction fiq_save_user_regs */
462 irq_save_user_regs
53677ef1 463 bl do_fiq
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464 irq_restore_user_regs
465
466#else
467
468 .align 5
469irq:
470 get_bad_stack
471 bad_save_user_regs
53677ef1 472 bl do_irq
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473
474 .align 5
475fiq:
476 get_bad_stack
477 bad_save_user_regs
53677ef1 478 bl do_fiq
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479
480#endif