90 lines
1.6 KiB
ArmAsm
90 lines
1.6 KiB
ArmAsm
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/*
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* Multiboot
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*/
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.set ALIGN, 1<<0 /* align loaded modules on page boundaries */
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.set MEMINFO, 1<<1 /* provide memory map */
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.set FLAGS, ALIGN | MEMINFO /* this is the Multiboot 'flag' field */
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.set MAGIC, 0x1BADB002 /* 'magic number' lets bootloader find the header */
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.set CHECKSUM, -(MAGIC + FLAGS) /* checksum of above, to prove we are multiboot */
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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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.section .bss
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.align 16
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stack_bottom:
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.skip 16384 # 16 KiB
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stack_top:
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.section .text
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.include "./src/kernel/arch/i386/irs_table.s"
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.include "./src/kernel/arch/i386/irq_table.s"
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.include "./src/kernel/arch/i386/idt/idt.s"
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.include "./src/kernel/arch/i386/paging.s"
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.global _start
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.type _start, @function
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_start:
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/*Setup the stack pointer to point to the beginning of our stack */
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/* I believe its a high address growing down to lower adress for the stack on x86*/
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mov $stack_top, %esp
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/*Reset EFLAGS*/
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pushl $0
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popf
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/* push the pointer to the Multiboot information structure*/
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pushl %ebx
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/* push the magic value */
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pushl %eax
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call early_main
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cli
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load_gdt:
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lgdt gdt
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# set the segment selecters
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movw $0x10, %ax
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movw %ax, %ds
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movw %ax, %es
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movw %ax, %fs
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movw %ax, %gs
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movw %ax, %ss
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ljmp $0x08, $flush
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flush:
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#load idt
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call init_idt
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sti
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# Try enable A20
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# mov $0x2401, %ax
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# int $0x15
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# enable protected mode
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mov %cr0, %eax
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or $1, %eax
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mov %eax, %cr0
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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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.include "./src/kernel/arch/i386/gdt/gdt.s"
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