2 * armboot - Startup Code for ARM925 CPU-core
4 * Copyright (c) 2003 Texas Instruments
6 * ----- Adapted for OMAP1510 from ARM920 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>
14 * See file CREDITS for list of people who contributed to this
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License as
19 * published by the Free Software Foundation; either version 2 of
20 * the License, or (at your option) any later version.
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
33 #include <asm-offsets.h>
38 *************************************************************************
40 * Jump vector table as in table 3.1 in [1]
42 *************************************************************************
48 ldr pc, _undefined_instruction
49 ldr pc, _software_interrupt
50 ldr pc, _prefetch_abort
56 _undefined_instruction: .word undefined_instruction
57 _software_interrupt: .word software_interrupt
58 _prefetch_abort: .word prefetch_abort
59 _data_abort: .word data_abort
60 _not_used: .word not_used
64 .balignl 16,0xdeadbeef
68 *************************************************************************
70 * Startup Code (reset vector)
72 * do important init only if we don't start from memory!
73 * setup Memory and board specific bits prior to relocation.
74 * relocate armboot to ram
77 *************************************************************************
82 #if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE)
83 .word CONFIG_SPL_TEXT_BASE
85 .word CONFIG_SYS_TEXT_BASE
89 * These are defined in the board-specific linker script.
90 * Subtracting _start from them lets the linker put their
91 * relative position in the executable instead of leaving
96 .word __bss_start - _start
100 .word __bss_end - _start
106 #ifdef CONFIG_USE_IRQ
107 /* IRQ stack memory (calculated at run-time) */
108 .globl IRQ_STACK_START
112 /* IRQ stack memory (calculated at run-time) */
113 .globl FIQ_STACK_START
118 /* IRQ stack memory (calculated at run-time) + 8 bytes */
119 .globl IRQ_STACK_START_IN
124 * the actual reset code
129 * set the cpu to SVC32 mode
139 mov r1, #0x81 /* Set ARM925T configuration. */
140 mcr p15, 0, r1, c15, c1, 0 /* Write ARM925T configuration register. */
143 * turn off the watchdog, unlock/diable sequence
152 * mask all IRQs by setting all bits in the INTMR - default
155 ldr r0, =REG_IHL1_MIR
157 ldr r0, =REG_IHL2_MIR
161 * wait for dpll to lock
172 * we do sys-critical inits only at reboot,
173 * not when booting from ram!
175 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
181 /*------------------------------------------------------------------------------*/
183 #ifndef CONFIG_SPL_BUILD
185 * void relocate_code(addr_moni)
187 * This function relocates the monitor code.
191 mov r6, r0 /* save addr of destination */
194 subs r9, r6, r0 /* r9 <- relocation offset */
195 beq relocate_done /* skip relocation */
196 mov r1, r6 /* r1 <- scratch for copy_loop */
197 ldr r3, _image_copy_end_ofs
198 add r2, r0, r3 /* r2 <- source end address */
201 ldmia r0!, {r10-r11} /* copy from source address [r0] */
202 stmia r1!, {r10-r11} /* copy to target address [r1] */
203 cmp r0, r2 /* until source end address [r2] */
207 * fix .rel.dyn relocations
209 ldr r0, _TEXT_BASE /* r0 <- Text base */
210 ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
211 add r10, r10, r0 /* r10 <- sym table in FLASH */
212 ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
213 add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
214 ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
215 add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
217 ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
218 add r0, r0, r9 /* r0 <- location to fix up in RAM */
221 cmp r7, #23 /* relative fixup? */
223 cmp r7, #2 /* absolute fixup? */
225 /* ignore unknown type of fixup */
228 /* absolute fix: set location to (offset) symbol value */
229 mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
230 add r1, r10, r1 /* r1 <- address of symbol in table */
231 ldr r1, [r1, #4] /* r1 <- symbol value */
232 add r1, r1, r9 /* r1 <- relocated sym addr */
235 /* relative fix: increase location by offset */
240 add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
249 .word __image_copy_end - _start
251 .word __rel_dyn_start - _start
253 .word __rel_dyn_end - _start
255 .word __dynsym_start - _start
259 .globl c_runtime_cpu_setup
265 *************************************************************************
267 * CPU_init_critical registers
269 * setup important registers
270 * setup memory timing
272 *************************************************************************
278 * flush v4 I/D caches
281 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
282 mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
285 * disable MMU stuff and caches
287 mrc p15, 0, r0, c1, c0, 0
288 bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
289 bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
290 orr r0, r0, #0x00000002 @ set bit 2 (A) Align
291 orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
292 mcr p15, 0, r0, c1, c0, 0
295 * Go setup Memory and board specific bits prior to relocation.
297 mov ip, lr /* perserve 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 */
302 *************************************************************************
306 *************************************************************************
312 #define S_FRAME_SIZE 72
334 #define MODE_SVC 0x13
338 * use bad_save_user_regs for abort/prefetch/undef/swi ...
339 * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
342 .macro bad_save_user_regs
343 sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current user stack
344 stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12
346 ldr r2, IRQ_STACK_START_IN
347 ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs)
348 add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
352 stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
353 mov r0, sp @ save current stack into r0 (param register)
356 .macro irq_save_user_regs
357 sub sp, sp, #S_FRAME_SIZE
358 stmia sp, {r0 - r12} @ Calling r0-r12
359 add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good.
360 stmdb r8, {sp, lr}^ @ Calling SP, LR
361 str lr, [r8, #0] @ Save calling PC
363 str r6, [r8, #4] @ Save CPSR
364 str r0, [r8, #8] @ Save OLD_R0
368 .macro irq_restore_user_regs
369 ldmia sp, {r0 - lr}^ @ Calling r0 - lr
371 ldr lr, [sp, #S_PC] @ Get PC
372 add sp, sp, #S_FRAME_SIZE
373 subs pc, lr, #4 @ return & move spsr_svc into cpsr
377 ldr r13, IRQ_STACK_START_IN
379 str lr, [r13] @ save caller lr in position 0 of saved stack
380 mrs lr, spsr @ get the spsr
381 str lr, [r13, #4] @ save spsr in position 1 of saved stack
383 mov r13, #MODE_SVC @ prepare SVC-Mode
385 msr spsr, r13 @ switch modes, make sure moves will execute
386 mov lr, pc @ capture return pc
387 movs pc, lr @ jump to next instruction & switch modes.
390 .macro get_irq_stack @ setup IRQ stack
391 ldr sp, IRQ_STACK_START
394 .macro get_fiq_stack @ setup FIQ stack
395 ldr sp, FIQ_STACK_START
402 undefined_instruction:
405 bl do_undefined_instruction
411 bl do_software_interrupt
431 #ifdef CONFIG_USE_IRQ
438 irq_restore_user_regs
443 /* someone ought to write a more effiction fiq_save_user_regs */
446 irq_restore_user_regs
467 ldr r1, rstctl1 /* get clkm1 reset ctl */
468 mov r3, #0x3 /* dsp_en + arm_rst = global reset */
469 strh r3, [r1] /* force reset */