forked from Bananymous/banan-os
85 lines
1.2 KiB
ArmAsm
85 lines
1.2 KiB
ArmAsm
.code16
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#########################################
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#
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# STAGE 1 BOOTLOADER
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#
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# its sole purpose is to load stage2 from
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# bios boot partition
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#
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#########################################
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.section .stage1
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.global stage1_main
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stage1_main:
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# setup segments
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movw $0, %ax
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movw %ax, %ds
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movw %ax, %es
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# setup stack
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movw %ax, %ss
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movl $0x7C00, %esp
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# save boot disk number
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call read_stage2_into_memory
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jmp stage2_main
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.global print_and_halt
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print_and_halt:
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call puts
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halt:
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hlt
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jmp halt
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#########################################
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#
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# STAGE 2 BOOTLOADER
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#
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#########################################
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.section .stage2
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stage2_main:
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# clear screen and enter 80x25 text mode
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movb $0x03, %al
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movb $0x00, %ah
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int $0x10
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# print hello message
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movw $hello_msg, %si
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call puts; call print_newline
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call get_memory_map
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call read_user_command_line
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call print_newline
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movw $start_kernel_load_msg, %si
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call puts; call print_newline
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call print_memory_map
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call find_root_disk
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call find_root_partition
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call print_root_partition_info
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call print_newline
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call has_ext2_filesystem
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testb %al, %al
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jz print_and_halt
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call ext2_find_kernel
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jmp halt
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hello_msg:
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.asciz "This is banan-os bootloader"
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start_kernel_load_msg:
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.asciz "Starting to load kernel"
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