52 lines
849 B
ArmAsm
Executable File
52 lines
849 B
ArmAsm
Executable File
.set ALIGN, 1<<0
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.set MEMINFO, 1<<1
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.set FLAGS, ALIGN | MEMINFO
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.set MAGIC, 0x1BADB002
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.set CHECKSUM, -(MAGIC + FLAGS)
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.section .multiboot
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.align 4
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.long MAGIC
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.long FLAGS
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.long CHECKSUM
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# C stack startup
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.section .bss
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.align 16
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stack_bottom:
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.skip 16384
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stack_top:
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# GDT segment register setup
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.global _gdt_flush
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.extern _gp
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_gdt_flush:
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lgdt (_gp) #load the GDT with the special pointer
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mov %ax, 0x10 #offset from GDT to data segment
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mov %ds, ax
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mov %es, ax
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mov %fs, ax
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mov %gs, ax
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mov %ss, ax
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jmp 0x08:flush2 #long jump
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flush2:
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ret #return to c code
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# start function - calls kernel_main
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.section .text
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.global _start
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.type _start, @function
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_start:
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movl $stack_top, %esp
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call _init
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call kernel_main
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cli
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1: hlt
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jmp 1b
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.size _start, . - _start |