32 lines
742 B
NASM
32 lines
742 B
NASM
; disk booting routines
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; these are only used during booting, they are not exposed via the jump table
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; load the boot sector of disk 0 to 0x00000800 and jump to it
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; inputs:
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; none
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; outputs:
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; none (doesn't return)
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start_boot_process:
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mov r0, 0x80003000 ; command to read a sector from disk 0 into memory
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mov r1, 0x80002000 ; command to set the location of the buffer
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; read sector 0 to 0x800
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out r1, 0x00000800
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out r0, 0
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; now clean up and jump to the loaded binary
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call boot_cleanup
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jmp 0x00000800
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; clean up the system's state before jumping to the loaded binary
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; inputs:
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; none
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; outputs:
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; none
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boot_cleanup:
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; clear the background
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mov r0, BACKGROUND_COLOR
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call fill_background
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ret
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