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/*
* armboot - Startup Code for ARM925 CPU-core
*
* Copyright (c) 2003 Texas Instruments
*
* ----- Adapted for OMAP1510 from ARM920 code ------
*
* Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
* Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
* Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
* Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
* Copyright (c) 2003 Kshitij <kshitij@ti.com>
*
* 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
*/
#include <asm-offsets.h>
#include <config.h>
#include <version.h>
/*
*************************************************************************
*
* Jump vector table as in table 3.1 in [1]
*
*************************************************************************
*/
.globl _start
_start: b reset
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
.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
*
*************************************************************************
*/
.globl _TEXT_BASE
_TEXT_BASE:
.word CONFIG_SYS_TEXT_BASE
/*
* These are defined in the board-specific linker script.
* Subtracting _start from them lets the linker put their
* relative position in the executable instead of leaving
* them null.
*/
.globl _bss_start_ofs
_bss_start_ofs:
.word __bss_start - _start
.globl _bss_end_ofs
_bss_end_ofs:
.word __bss_end__ - _start
.globl _end_ofs
_end_ofs:
.word _end - _start
#ifdef CONFIG_USE_IRQ
/* IRQ stack memory (calculated at run-time) */
.globl IRQ_STACK_START
IRQ_STACK_START:
.word 0x0badc0de
/* IRQ stack memory (calculated at run-time) */
.globl FIQ_STACK_START
FIQ_STACK_START:
.word 0x0badc0de
#endif
/* IRQ stack memory (calculated at run-time) + 8 bytes */
.globl IRQ_STACK_START_IN
IRQ_STACK_START_IN:
.word 0x0badc0de
/*
* the actual reset code
*/
reset:
/*
* set the cpu to SVC32 mode
*/
mrs r0,cpsr
bic r0,r0,#0x1f
orr r0,r0,#0xd3
msr cpsr,r0
/*
* Set up 925T mode
*/
mov r1, #0x81 /* Set ARM925T configuration. */
mcr p15, 0, r1, c15, c1, 0 /* Write ARM925T configuration register. */
/*
* turn off the watchdog, unlock/diable sequence
*/
mov r1, #0xF5
ldr r0, =WDTIM_MODE
strh r1, [r0]
mov r1, #0xA0
strh r1, [r0]
/*
* mask all IRQs by setting all bits in the INTMR - default
*/
mov r1, #0xffffffff
ldr r0, =REG_IHL1_MIR
str r1, [r0]
ldr r0, =REG_IHL2_MIR
str r1, [r0]
/*
* wait for dpll to lock
*/
ldr r0, =CK_DPLL1
mov r1, #0x10
strh r1, [r0]
poll1:
ldrh r1, [r0]
ands r1, r1, #0x01
beq poll1
/*
* we do sys-critical inits only at reboot,
* not when booting from ram!
*/
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
bl cpu_init_crit
#endif
bl _main
/*------------------------------------------------------------------------------*/
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
*/
.globl relocate_code
relocate_code:
mov r4, r0 /* save addr_sp */
mov r5, r1 /* save addr of gd */
mov r6, r2 /* save addr of destination */
adr r0, _start
cmp r0, r6
moveq r9, #0 /* no relocation. relocation offset(r9) = 0 */
beq relocate_done /* skip relocation */
mov r1, r6 /* r1 <- scratch for copy_loop */
ldr r3, _bss_start_ofs
add r2, r0, r3 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r9-r10} /* copy from source address [r0] */
stmia r1!, {r9-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end address [r2] */
blo copy_loop
#ifndef CONFIG_SPL_BUILD
/*
* fix .rel.dyn relocations
*/
ldr r0, _TEXT_BASE /* r0 <- Text base */
sub r9, r6, r0 /* r9 <- relocation offset */
ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
add r10, r10, r0 /* r10 <- sym table in FLASH */
ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
fixloop:
ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
add r0, r0, r9 /* r0 <- location to fix up in RAM */
ldr r1, [r2, #4]
and r7, r1, #0xff
cmp r7, #23 /* relative fixup? */
beq fixrel
cmp r7, #2 /* absolute fixup? */
beq fixabs
/* ignore unknown type of fixup */
b fixnext
fixabs:
/* absolute fix: set location to (offset) symbol value */
mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
add r1, r10, r1 /* r1 <- address of symbol in table */
ldr r1, [r1, #4] /* r1 <- symbol value */
add r1, r1, r9 /* r1 <- relocated sym addr */
b fixnext
fixrel:
/* relative fix: increase location by offset */
ldr r1, [r0]
add r1, r1, r9
fixnext:
str r1, [r0]
add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
cmp r2, r3
blo fixloop
#endif
relocate_done:
mov pc, lr
_rel_dyn_start_ofs:
.word __rel_dyn_start - _start
_rel_dyn_end_ofs:
.word __rel_dyn_end - _start
_dynsym_start_ofs:
.word __dynsym_start - _start
.globl c_runtime_cpu_setup
c_runtime_cpu_setup:
mov pc, lr
/*
*************************************************************************
*
* CPU_init_critical registers
*
* setup important registers
* setup memory timing
*
*************************************************************************
*/
cpu_init_crit:
/*
* 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
mcr p15, 0, r0, c1, c0, 0
/*
* Go setup Memory and board specific bits prior to relocation.
*/
mov ip, lr /* perserve link reg across call */
bl lowlevel_init /* go setup pll,mux,memory */
mov lr, ip /* restore link */
mov pc, lr /* back to my caller */
/*
*************************************************************************
*
* 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 ...
* use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
*/
.macro bad_save_user_regs
sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current user stack
stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12
ldr r2, IRQ_STACK_START_IN
ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs)
add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
add r5, sp, #S_SP
mov r1, lr
stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
mov r0, sp @ save current stack into r0 (param register)
.endm
.macro irq_save_user_regs
sub sp, sp, #S_FRAME_SIZE
stmia sp, {r0 - r12} @ Calling r0-r12
add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good.
stmdb r8, {sp, lr}^ @ Calling SP, LR
str lr, [r8, #0] @ Save calling PC
mrs r6, spsr
str r6, [r8, #4] @ Save CPSR
str r0, [r8, #8] @ Save OLD_R0
mov r0, sp
.endm
.macro irq_restore_user_regs
ldmia sp, {r0 - lr}^ @ Calling r0 - lr
mov r0, r0
ldr lr, [sp, #S_PC] @ Get PC
add sp, sp, #S_FRAME_SIZE
subs pc, lr, #4 @ return & move spsr_svc into cpsr
.endm
.macro get_bad_stack
ldr r13, IRQ_STACK_START_IN
str lr, [r13] @ save caller lr in position 0 of saved stack
mrs lr, spsr @ get the spsr
str lr, [r13, #4] @ save spsr in position 1 of saved stack
mov r13, #MODE_SVC @ prepare SVC-Mode
@ msr spsr_c, r13
msr spsr, r13 @ switch modes, make sure moves will execute
mov lr, pc @ capture return pc
movs pc, lr @ jump to next instruction & switch modes.
.endm
.macro get_irq_stack @ setup IRQ stack
ldr sp, IRQ_STACK_START
.endm
.macro get_fiq_stack @ setup FIQ stack
ldr sp, FIQ_STACK_START
.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
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
#ifdef CONFIG_USE_IRQ
.align 5
irq:
get_irq_stack
irq_save_user_regs
bl do_irq
irq_restore_user_regs
.align 5
fiq:
get_fiq_stack
/* someone ought to write a more effiction fiq_save_user_regs */
irq_save_user_regs
bl do_fiq
irq_restore_user_regs
#else
.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
.align 5
.globl reset_cpu
reset_cpu:
ldr r1, rstctl1 /* get clkm1 reset ctl */
mov r3, #0x3 /* dsp_en + arm_rst = global reset */
strh r3, [r1] /* force reset */
mov r0, r0
_loop_forever:
b _loop_forever
rstctl1:
.word 0xfffece10