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1 #include "arm.h"
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2 #include "memlayout.h"
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3
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4 .text
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5 .code 32
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6
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7 .global _start
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8
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9 _start:
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10 # clear the entry bss section, the svc stack, and kernel page table
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11 LDR r1, =edata_entry
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12 LDR r2, =end_entry
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13 MOV r3, #0x00
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14
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15 1:
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16 CMP r1, r2
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17 STMIALT r1!, {r3}
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18 BLT 1b
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19
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20 # initialize stack pointers for svc modes
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21 MSR CPSR_cxsf, #(SVC_MODE|NO_INT)
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22 LDR sp, =svc_stktop
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23
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24 BL start
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25 B .
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26
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27 # during startup, kernel stack uses user address, now switch it to kernel addr
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28 .global jump_stack
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29 jump_stack:
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30 MOV r0, sp
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31 ADD r0, r0, #KERNBASE
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32 MOV sp, r0
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33 MOV pc, lr
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