226 lines
5.5 KiB
ArmAsm
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// multiboot2
// How many bytes from the start of the file we search for the header.
#define MULTIBOOT_SEARCH 32768
#define MULTIBOOT_HEADER_ALIGN 8
// The magic field should contain this.
#define MULTIBOOT2_HEADER_MAGIC 0xe85250d6
// This should be in %eax.
#define MULTIBOOT2_BOOTLOADER_MAGIC 0x36d76289
// Alignment of multiboot modules.
#define MULTIBOOT_MOD_ALIGN 0x00001000
// Alignment of the multiboot info structure.
#define MULTIBOOT_INFO_ALIGN 0x00000008
// Flags set in the 'flags' member of the multiboot header.
#define MULTIBOOT_TAG_ALIGN 8
#define MULTIBOOT_TAG_TYPE_END 0
#define MULTIBOOT_TAG_TYPE_CMDLINE 1
#define MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME 2
#define MULTIBOOT_TAG_TYPE_MODULE 3
#define MULTIBOOT_TAG_TYPE_BASIC_MEMINFO 4
#define MULTIBOOT_TAG_TYPE_BOOTDEV 5
#define MULTIBOOT_TAG_TYPE_MMAP 6
#define MULTIBOOT_TAG_TYPE_VBE 7
#define MULTIBOOT_TAG_TYPE_FRAMEBUFFER 8
#define MULTIBOOT_TAG_TYPE_ELF_SECTIONS 9
#define MULTIBOOT_TAG_TYPE_APM 10
#define MULTIBOOT_TAG_TYPE_EFI32 11
#define MULTIBOOT_TAG_TYPE_EFI64 12
#define MULTIBOOT_TAG_TYPE_SMBIOS 13
#define MULTIBOOT_TAG_TYPE_ACPI_OLD 14
#define MULTIBOOT_TAG_TYPE_ACPI_NEW 15
#define MULTIBOOT_TAG_TYPE_NETWORK 16
#define MULTIBOOT_TAG_TYPE_EFI_MMAP 17
#define MULTIBOOT_TAG_TYPE_EFI_BS 18
#define MULTIBOOT_TAG_TYPE_EFI32_IH 19
#define MULTIBOOT_TAG_TYPE_EFI64_IH 20
#define MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDR 21
#define MULTIBOOT_HEADER_TAG_END 0
#define MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST 1
#define MULTIBOOT_HEADER_TAG_ADDRESS 2
#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS 3
#define MULTIBOOT_HEADER_TAG_CONSOLE_FLAGS 4
#define MULTIBOOT_HEADER_TAG_FRAMEBUFFER 5
#define MULTIBOOT_HEADER_TAG_MODULE_ALIGN 6
#define MULTIBOOT_HEADER_TAG_EFI_BS 7
#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI32 8
#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI64 9
#define MULTIBOOT_HEADER_TAG_RELOCATABLE 10
#define MULTIBOOT_ARCHITECTURE_I386 0
#define MULTIBOOT_ARCHITECTURE_MIPS32 4
#define MULTIBOOT_HEADER_TAG_OPTIONAL 1
#define MULTIBOOT_LOAD_PREFERENCE_NONE 0
#define MULTIBOOT_LOAD_PREFERENCE_LOW 1
#define MULTIBOOT_LOAD_PREFERENCE_HIGH 2
#define MULTIBOOT_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
#define MULTIBOOT_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
// -m64 64
// 32 32 64
// 64 -m32 long -m64
// x86_64(IA32E)
// See https://wiki.osdev.org/Creating_a_64-bit_kernel:
// With a 32-bit bootstrap in your kernel
// long
// 32bit
// 32
.code32
// multiboot2
//
.SET HEADER_LENGTH, multiboot_header_end - multiboot_header
//
.SET CHECKSUM, -(MULTIBOOT2_HEADER_MAGIC + MULTIBOOT_ARCHITECTURE_I386 + HEADER_LENGTH)
// 8
.align MULTIBOOT_HEADER_ALIGN
//
.section .multiboot_header
multiboot_header:
//
.long MULTIBOOT2_HEADER_MAGIC
//
.long MULTIBOOT_ARCHITECTURE_I386
//
.long HEADER_LENGTH
//
.long CHECKSUM
// Multiboot2 Specification version 2.0.pdf
.short MULTIBOOT_HEADER_TAG_END
//
.short 0
.long 8
multiboot_header_end:
// 4KB/
.section .data
.align 0x1000
pml4:
.skip 0x1000
pdpt:
.skip 0x1000
pd:
.skip 0x1000
pt:
.skip 0x1000
// GDT
.align 16
gdt64:
null_desc:
.short 0xFFFF
.short 0
.byte 0
.byte 0
.byte 0
.byte 0
code_desc:
.short 0
.short 0
.byte 0
.byte 0x9A
.byte 0x20
.byte 0
data_desc:
.short 0
.short 0
.byte 0
.byte 0x92
.byte 0
.byte 0
user_code_desc:
.short 0
.short 0
.byte 0
.byte 0xFA
.byte 0x20
.byte 0
user_data_desc:
.short 0
.short 0
.byte 0
.byte 0xF2
.byte 0
.byte 0
gdt64_pointer:
.short gdt64_pointer-gdt64-1
.quad gdt64
gdt64_pointer64:
.short gdt64_pointer-gdt64-1
.quad gdt64
.section .text
.global _start
.type _start, @function
# multiboot2.cpp
.extern boot_info_addr
.extern multiboot2_magic
_start:
//
cli
// multiboot2_info
//mov %ebx, boot_info_addr
//
// mov %eax, multiboot2_magic
//
// 1. PAE
mov %cr4, %eax
or $(1<<5), %eax
mov %eax, %cr4
// 2.
//
mov $pml4, %eax
mov $pdpt, %ebx
or $0x3, %ebx
mov %ebx, 0(%eax)
//
mov $pdpt, %eax
mov $pd, %ebx
or $0x3, %ebx
mov %ebx, 0(%eax)
//
mov $pd, %eax
mov $pt, %ebx
or $0x3, %ebx
mov %ebx, 0(%eax)
//
// 512
mov $512, %ecx
mov $pt, %eax
mov $0x3, %ebx
.fill_pt:
mov %ebx, 0(%eax)
add $0x1000, %ebx
add $8, %eax
loop .fill_pt
// CR3
mov $pml4, %eax
mov %eax, %cr3
// 3. long
mov $0xC0000080, %ecx
rdmsr
or $(1<<8), %eax
wrmsr
// 4.
mov %cr0, %eax
or $(1<<31), %eax
mov %eax, %cr0
// 5. GDT
mov $gdt64_pointer, %eax
lgdt 0(%eax)
// 6. 64
jmp $0x8, $_start64
hlt
ret