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https://github.com/vivier/EMILE.git
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121 lines
1.9 KiB
ArmAsm
121 lines
1.9 KiB
ArmAsm
/*
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*
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* (c) 2004 Laurent Vivier <LaurentVivier@wanadoo.fr>
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*
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*/
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.macro NewPtr
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.short 0xA11E
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.endm
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.equ cmdline_length, 256 /* see CL_SIZE in bootinfo.c */
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.global _start
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_start:
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bra setup
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/***************************************************************************
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*
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* second level arguments
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*
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***************************************************************************/
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/* Header Signature */
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.dc.b 'E','M','0','1'
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_kernel_image_offset:
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.long 0
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_kernel_image_size:
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.long 0
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_kernel_size:
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.long 0
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_ramdisk_offset:
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.long 0
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_ramdisk_size:
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.long 0
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_command_line:
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.skip cmdline_length, 0
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.align 4
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setup:
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/* relocate C code, need to be compiled with -fpic */
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bsr relocate
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/* initialize console, so we can debug ;-) */
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bsr console_init@PLTPC
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/* begin to work */
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lea _command_line(%pc), %a0
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move.l %a0, -(%sp)
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move.l _ramdisk_size(%pc), -(%sp)
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move.l _ramdisk_offset(%pc), -(%sp)
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move.l _kernel_size(%pc), -(%sp)
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move.l _kernel_image_size(%pc), -(%sp)
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move.l _kernel_image_offset(%pc), -(%sp)
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bsr start@PLTPC
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/* We guess to never come here */
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loop:
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bra loop
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relocate:
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/* Allocate BSS section */
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move.l #__bss_size, %d0 /* size */
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NewPtr /* result in %a0 */
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move.l %a0,%d3
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move.l #__bss_start, %d0
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sub.l %d0,%d3 /* %d3 is the offset to add for BSS */
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/* real address of GOT */
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lea (%pc, _GLOBAL_OFFSET_TABLE_@GOTPC), %a0
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/* linked address of GOT */
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move.l #_GLOBAL_OFFSET_TABLE_, %d0
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/* %d2 is the offset to add for all other sections */
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move.l %a0,%d2
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sub.l %d0,%d2
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/* relocate BSS section */
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move.l #__got_size, %d0
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beq exit_relocate
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got_loop:
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move.l (%a0), %d1
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cmp.l #__bss_start.l, %d1
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blt other_section
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cmp.l #_end.l, %d1
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bgt other_section
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/* symbol in section BSS */
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add.l %d3, %d1
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bra got_store
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other_section:
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add.l %d2, %d1
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got_store:
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move.l %d1, (%a0)+
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subq.l #4, %d0
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bgt got_loop
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exit_relocate:
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rts
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