38 lines
779 B
ArmAsm
38 lines
779 B
ArmAsm
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/* Tell processor to use our gdt*/
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gdt:
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.word (gdt_end - gdt_start -1) # Size of the GDT in bytes minus 1 for math reasons
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.int gdt_start # linear address of our GDT
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.att_syntax
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.size _start, . - _start
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/*
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* Create the GDT
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*/
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.section .data
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gdt_start:
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gdt_null:
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.long 0x0
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.long 0x0
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gdt_kcode:
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.word 0xFFFF # limit
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.word 0x0 # base
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.byte 0x0 # base
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.byte 0b10011010 # 1st flags | type flags
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.byte 0b11001111 # 2nd flags | limit
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.byte 0x0 # base
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gdt_kdata:
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.word 0xFFFF # limit
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.word 0x0 # base
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.byte 0x0 # base
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.byte 0b10010010 # 1st flags | type flags
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.byte 0b11001111 # 2nd flags | limit
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.byte 0x0 # base
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gdt_end:
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