2 * armboot - Startup Code for ARM926EJS CPU-core
4 * Copyright (c) 2003 Texas Instruments
6 * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------
8 * Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
9 * Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
10 * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
11 * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
12 * Copyright (c) 2003 Kshitij <kshitij@ti.com>
13 * Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net>
15 * See file CREDITS for list of people who contributed to this
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License as
20 * published by the Free Software Foundation; either version 2 of
21 * the License, or (at your option) any later version.
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
34 #include <asm-offsets.h>
39 #if defined(CONFIG_OMAP1610)
40 #include <./configs/omap1510.h>
41 #elif defined(CONFIG_OMAP730)
42 #include <./configs/omap730.h>
46 *************************************************************************
48 * Jump vector table as in table 3.1 in [1]
50 *************************************************************************
54 #ifdef CONFIG_SYS_DV_NOR_BOOT_CFG
59 .word CONFIG_SYS_DV_NOR_BOOT_CFG
66 #ifdef CONFIG_SPL_BUILD
67 /* No exception handlers in preloader */
78 /* pad to 64 byte boundary */
87 ldr pc, _undefined_instruction
88 ldr pc, _software_interrupt
89 ldr pc, _prefetch_abort
95 _undefined_instruction:
96 .word undefined_instruction
98 .word software_interrupt
110 #endif /* CONFIG_SPL_BUILD */
111 .balignl 16,0xdeadbeef
115 *************************************************************************
117 * Startup Code (reset vector)
119 * do important init only if we don't start from memory!
120 * setup Memory and board specific bits prior to relocation.
121 * relocate armboot to ram
124 *************************************************************************
129 #ifdef CONFIG_NAND_SPL /* deprecated, use instead CONFIG_SPL_BUILD */
130 .word CONFIG_SYS_TEXT_BASE
132 #ifdef CONFIG_SPL_BUILD
133 .word CONFIG_SPL_TEXT_BASE
135 .word CONFIG_SYS_TEXT_BASE
140 * These are defined in the board-specific linker script.
141 * Subtracting _start from them lets the linker put their
142 * relative position in the executable instead of leaving
145 .globl _bss_start_ofs
147 .word __bss_start - _start
151 .word __bss_end__ - _start
157 #ifdef CONFIG_NAND_U_BOOT
163 #ifdef CONFIG_USE_IRQ
164 /* IRQ stack memory (calculated at run-time) */
165 .globl IRQ_STACK_START
169 /* IRQ stack memory (calculated at run-time) */
170 .globl FIQ_STACK_START
175 /* IRQ stack memory (calculated at run-time) + 8 bytes */
176 .globl IRQ_STACK_START_IN
181 * the actual reset code
186 * set the cpu to SVC32 mode
194 * we do sys-critical inits only at reboot,
195 * not when booting from ram!
197 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
201 /* Set stackpointer in internal RAM to call board_init_f */
203 #ifdef CONFIG_NAND_SPL /* deprecated, use instead CONFIG_SPL_BUILD */
204 ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
206 #ifdef CONFIG_SPL_BUILD
207 ldr sp, =(CONFIG_SPL_STACK)
209 ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
212 bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
216 /*------------------------------------------------------------------------------*/
219 * void relocate_code (addr_sp, gd, addr_moni)
221 * This "function" does not return, instead it continues in RAM
222 * after relocating the monitor code.
227 mov r4, r0 /* save addr_sp */
228 mov r5, r1 /* save addr of gd */
229 mov r6, r2 /* save addr of destination */
231 /* Set up the stack */
236 sub r9, r6, r0 /* r9 <- relocation offset */
238 beq clear_bss /* skip relocation */
239 mov r1, r6 /* r1 <- scratch for copy loop */
240 ldr r3, _bss_start_ofs
241 add r2, r0, r3 /* r2 <- source end address */
244 ldmia r0!, {r9-r10} /* copy from source address [r0] */
245 stmia r1!, {r9-r10} /* copy to target address [r1] */
246 cmp r0, r2 /* until source end address [r2] */
249 #ifndef CONFIG_SPL_BUILD
251 * fix .rel.dyn relocations
253 ldr r0, _TEXT_BASE /* r0 <- Text base */
254 sub r9, r6, r0 /* r9 <- relocation offset */
255 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
256 add r10, r10, r0 /* r10 <- sym table in FLASH */
257 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
258 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
259 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
260 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
262 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
263 add r0, r0, r9 /* r0 <- location to fix up in RAM */
266 cmp r7, #23 /* relative fixup? */
268 cmp r7, #2 /* absolute fixup? */
270 /* ignore unknown type of fixup */
273 /* absolute fix: set location to (offset) symbol value */
274 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
275 add r1, r10, r1 /* r1 <- address of symbol in table */
276 ldr r1, [r1, #4] /* r1 <- symbol value */
277 add r1, r1, r9 /* r1 <- relocated sym addr */
280 /* relative fix: increase location by offset */
285 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
291 #ifdef CONFIG_SPL_BUILD
292 /* No relocation for SPL */
296 ldr r0, _bss_start_ofs
298 mov r4, r6 /* reloc addr */
302 mov r2, #0x00000000 /* clear */
304 clbss_l:cmp r0, r1 /* clear loop... */
305 bhs clbss_e /* if reached end of bss, exit */
311 #ifndef CONFIG_SPL_BUILD
317 * We are done. Do not return, instead branch to second part of board
318 * initialization, now running from RAM.
320 #ifdef CONFIG_NAND_SPL
321 ldr r0, _nand_boot_ofs
327 ldr r0, _board_init_r_ofs
331 /* setup parameters for board_init_r */
332 mov r0, r5 /* gd_t */
333 mov r1, r6 /* dest_addr */
338 .word board_init_r - _start
342 .word __rel_dyn_start - _start
344 .word __rel_dyn_end - _start
346 .word __dynsym_start - _start
349 *************************************************************************
351 * CPU_init_critical registers
353 * setup important registers
354 * setup memory timing
356 *************************************************************************
358 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
361 * flush v4 I/D caches
364 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
365 mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
368 * disable MMU stuff and caches
370 mrc p15, 0, r0, c1, c0, 0
371 bic r0, r0, #0x00002300 /* clear bits 13, 9:8 (--V- --RS) */
372 bic r0, r0, #0x00000087 /* clear bits 7, 2:0 (B--- -CAM) */
373 orr r0, r0, #0x00000002 /* set bit 2 (A) Align */
374 orr r0, r0, #0x00001000 /* set bit 12 (I) I-Cache */
375 mcr p15, 0, r0, c1, c0, 0
378 * Go setup Memory and board specific bits prior to relocation.
380 mov ip, lr /* perserve link reg across call */
381 bl lowlevel_init /* go setup pll,mux,memory */
382 mov lr, ip /* restore link */
383 mov pc, lr /* back to my caller */
384 #endif /* CONFIG_SKIP_LOWLEVEL_INIT */
386 #ifndef CONFIG_SPL_BUILD
388 *************************************************************************
392 *************************************************************************
398 #define S_FRAME_SIZE 72
420 #define MODE_SVC 0x13
424 * use bad_save_user_regs for abort/prefetch/undef/swi ...
425 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
428 .macro bad_save_user_regs
429 @ carve out a frame on current user stack
430 sub sp, sp, #S_FRAME_SIZE
431 stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12
432 ldr r2, IRQ_STACK_START_IN
433 @ get values for "aborted" pc and cpsr (into parm regs)
435 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
438 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
439 mov r0, sp @ save current stack into r0 (param register)
442 .macro irq_save_user_regs
443 sub sp, sp, #S_FRAME_SIZE
444 stmia sp, {r0 - r12} @ Calling r0-r12
445 @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good.
447 stmdb r8, {sp, lr}^ @ Calling SP, LR
448 str lr, [r8, #0] @ Save calling PC
450 str r6, [r8, #4] @ Save CPSR
451 str r0, [r8, #8] @ Save OLD_R0
455 .macro irq_restore_user_regs
456 ldmia sp, {r0 - lr}^ @ Calling r0 - lr
458 ldr lr, [sp, #S_PC] @ Get PC
459 add sp, sp, #S_FRAME_SIZE
460 subs pc, lr, #4 @ return & move spsr_svc into cpsr
464 ldr r13, IRQ_STACK_START_IN @ setup our mode stack
466 str lr, [r13] @ save caller lr in position 0 of saved stack
467 mrs lr, spsr @ get the spsr
468 str lr, [r13, #4] @ save spsr in position 1 of saved stack
469 mov r13, #MODE_SVC @ prepare SVC-Mode
471 msr spsr, r13 @ switch modes, make sure moves will execute
472 mov lr, pc @ capture return pc
473 movs pc, lr @ jump to next instruction & switch modes.
476 .macro get_irq_stack @ setup IRQ stack
477 ldr sp, IRQ_STACK_START
480 .macro get_fiq_stack @ setup FIQ stack
481 ldr sp, FIQ_STACK_START
483 #endif /* CONFIG_SPL_BUILD */
488 #ifdef CONFIG_SPL_BUILD
491 ldr sp, _TEXT_BASE /* switch to abort stack */
493 bl 1b /* hang and never return */
494 #else /* !CONFIG_SPL_BUILD */
496 undefined_instruction:
499 bl do_undefined_instruction
505 bl do_software_interrupt
525 #ifdef CONFIG_USE_IRQ
532 irq_restore_user_regs
537 /* someone ought to write a more effiction fiq_save_user_regs */
540 irq_restore_user_regs
557 #endif /* CONFIG_SPL_BUILD */