95 lines
1.9 KiB
ArmAsm
95 lines
1.9 KiB
ArmAsm
#include <linux/linkage.h>
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#include <asm/sections.h>
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.section .text.setupc
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/*
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* setup_c: copy binary to link address, clear bss and
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* continue executing at new address.
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*
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* This function does not return to the address it is
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* called from, but to the same location in the copied
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* binary.
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*/
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ENTRY(setup_c)
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push {r4, r5}
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mov r5, lr
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bl get_runtime_offset
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subs r4, r0, #0
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beq 1f /* skip memcpy if already at correct address */
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ldr r0,=_text
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ldr r2,=__bss_start
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sub r2, r2, r0
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sub r1, r0, r4
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bl memcpy /* memcpy(_text, _text - offset, __bss_start - _text) */
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1: ldr r0, =__bss_start
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mov r1, #0
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ldr r2, =__bss_stop
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sub r2, r2, r0
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bl memset /* clear bss */
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#ifdef CONFIG_MMU
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bl arm_early_mmu_cache_flush
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#endif
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mov r0, #0
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mcr p15, 0, r0, c7, c5, 0 /* flush icache */
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add lr, r5, r4 /* adjust return address to new location */
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pop {r4, r5}
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mov pc, lr
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ENDPROC(setup_c)
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/*
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* void relocate_to_adr(unsigned long targetadr)
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*
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* Copy binary to targetadr, relocate code and continue
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* executing at new address.
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*/
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.section .text.relocate_to_adr
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ENTRY(relocate_to_adr)
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/* r0: target address */
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push {r3, r4, r5, r6, r7, r8}
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mov r7, lr
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mov r6, r0
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bl get_runtime_offset
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mov r5, r0
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ld_var _text, r0, r4
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mov r8, r0
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sub r1, r0, r5 /* r1: from address */
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cmp r1, r6 /* already at correct address? */
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beq 1f /* yes, skip copy to new address */
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ld_var __bss_start, r2, r4
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sub r2, r2, r0 /* r2: size */
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mov r0, r6 /* r0: target */
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add r7, r7, r0 /* adjust return address */
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sub r7, r7, r1 /* lr += offset */
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bl memcpy /* copy binary */
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#ifdef CONFIG_MMU
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bl arm_early_mmu_cache_flush
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#endif
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mov r0,#0
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mcr p15, 0, r0, c7, c5, 0 /* flush icache */
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ldr r0,=1f
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sub r0, r0, r8
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add r0, r0, r6
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mov pc, r0 /* jump to relocated address */
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1:
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bl relocate_to_current_adr /* relocate binary */
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mov lr, r7
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pop {r3, r4, r5, r6, r7, r8}
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mov pc, lr
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ENDPROC(relocate_to_adr)
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