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/*
* startup code
*
*/
#define PSR_MODE 0x0000001f
#define PSR_USR_MODE 0x00000010
#define PSR_IRQ_MODE 0x00000012
#define PSR_SVC_MODE 0x00000013
#define PSR_INT_MASK 0x000000c0
#define PSR_FIQ_DIS 0x00000040
#define PSR_IRQ_DIS 0x00000080
.section .init.text,"ax",%progbits
.global start
.extern _interrupt_disable
/* -----------------------------------------------------
* startup code (setup stacks, branch to main)
* -----------------------------------------------------
*/
start:
/* setup IRQ stack */
mov r0,#(PSR_IRQ_MODE|PSR_FIQ_DIS|PSR_IRQ_DIS)
msr cpsr,r0
ldr sp,=irqstackend
/* setup SVC stack */
mov r0,#(PSR_SVC_MODE|PSR_FIQ_DIS|PSR_IRQ_DIS)
msr cpsr,r0
ldr sp,=stackend
/* disbale interrupts */
mrs r0,cpsr
orr r0,r0,#0xc0
msr cpsr_c, r0
/* remap */
mov r0,#0x18000000
add r0,r0,#0x1C000
ldr r1,=0xdeadbeef
str r1,[r0,#4]
/* relocate itself */
ldr r0,=_relocstart
ldr r1,=_relocend
ldr r2,=0x0
1:
cmp r1,r0
ldrhi r3,[r0],#4
strhi r3,[r2],#4
bhi 1b
/* continue running in SVC (supervisor mode) */
ldr pc,=0x0
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