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authorXander <xander@icth.xyz>2023-06-28 21:56:30 +0200
committerXander <xander@icth.xyz>2023-06-28 21:56:30 +0200
commit448ecd41edd95b86930b5ac7288f2ea9311d476c (patch)
tree64106ce37ea5c6067835ce747dd650a5e01a4c1e /src
parentfd86b8a4769860f22fc04ce3b80510d809f68d3c (diff)
downloadats-os-448ecd41edd95b86930b5ac7288f2ea9311d476c.tar.xz
ats-os-448ecd41edd95b86930b5ac7288f2ea9311d476c.zip
Reorganizing
Diffstat (limited to 'src')
-rw-r--r--src/arch/x86_64/boot.asm163
-rw-r--r--src/arch/x86_64/grub.cfg7
-rw-r--r--src/arch/x86_64/linker.ld16
-rw-r--r--src/arch/x86_64/long_mode_init.asm17
-rw-r--r--src/arch/x86_64/multiboot_header.asm15
5 files changed, 0 insertions, 218 deletions
diff --git a/src/arch/x86_64/boot.asm b/src/arch/x86_64/boot.asm
deleted file mode 100644
index 2e334a8..0000000
--- a/src/arch/x86_64/boot.asm
+++ /dev/null
@@ -1,163 +0,0 @@
-global start
-extern long_mode_start
-
-section .text
-bits 32
-start:
- mov esp, stack_top
-
- call check_multiboot
- call check_cpuid
- call check_long_mode
-
- call set_up_page_tables
- call enable_paging
-
- ; load the 64-bit GDT
- lgdt [gdt64.pointer]
-
- jmp gdt64.code:long_mode_start
-
- ; print `OK` to screen
- mov dword [0xb8000], 0x2f4b2f4f
- hlt
-
-check_multiboot:
- cmp eax, 0x36d76289
- jne .no_multiboot
- ret
-.no_multiboot:
- mov al, "0"
- jmp error
-
-check_cpuid:
- ; Check if CPUID is supported by attempting to flip the ID bit (bit 21)
- ; in the FLAGS register. If we can flip it, CPUID is available.
-
- ; Copy FLAGS in to EAX via stack
- pushfd
- pop eax
-
- ; Copy to ECX as well for comparing later on
- mov ecx, eax
-
- ; Flip the ID bit
- xor eax, 1 << 21
-
- ; Copy EAX to FLAGS via the stack
- push eax
- popfd
-
- ; Copy FLAGS back to EAX (with the flipped bit if CPUID is supported)
- pushfd
- pop eax
-
- ; Restore FLAGS from the old version stored in ECX (i.e. flipping the
- ; ID bit back if it was ever flipped).
- push ecx
- popfd
-
- ; Compare EAX and ECX. If they are equal then that means the bit
- ; wasn't flipped, and CPUID isn't supported.
- cmp eax, ecx
- je .no_cpuid
- ret
-.no_cpuid:
- mov al, "1"
- jmp error
-
-check_long_mode:
- ; test if extended processor info in available
- mov eax, 0x80000000 ; implicit argument for cpuid
- cpuid ; get highest supported argument
- cmp eax, 0x80000001 ; it needs to be at least 0x80000001
- jb .no_long_mode ; if it's less, the CPU is too old for long mode
-
- ; use extended info to test if long mode is available
- mov eax, 0x80000001 ; argument for extended processor info
- cpuid ; returns various feature bits in ecx and edx
- test edx, 1 << 29 ; test if the LM-bit is set in the D-register
- jz .no_long_mode ; If it's not set, there is no long mode
- ret
-.no_long_mode:
- mov al, "2"
- jmp error
-
-; Prints `ERR: ` and the given error code to screen and hangs.
-; parameter: error code (in ascii) in al
-error:
- mov dword [0xb8000], 0x4f524f45
- mov dword [0xb8004], 0x4f3a4f52
- mov dword [0xb8008], 0x4f204f20
- mov byte [0xb800a], al
- hlt
-
-set_up_page_tables:
- ; map first P4 entry to P3 table
- mov eax, p3_table
- or eax, 0b11 ; present + writable
- mov [p4_table], eax
-
- ; map first P3 entry to P2 table
- mov eax, p2_table
- or eax, 0b11 ; present + writable
- mov [p3_table], eax
-
- ; map each P2 entry to a huge 2MiB page
- mov ecx, 0 ; counter variable
-.map_p2_table:
- ; map ecx-th P2 entry to a huge page that starts at address 2MiB*ecx
- mov eax, 0x200000 ; 2MiB
- mul ecx ; start address of ecx-th page
- or eax, 0b10000011 ; present + writable + huge
- mov [p2_table + ecx * 8], eax ; map ecx-th entry
-
- inc ecx ; increase counter
- cmp ecx, 512 ; if counter == 512, the whole P2 table is mapped
- jne .map_p2_table ; else map the next entry
-
- ret
-
-enable_paging:
- ; load P4 to cr3 register (cpu uses this to access the P4 table)
- mov eax, p4_table
- mov cr3, eax
-
- ; enable PAE-flag in cr4 (Physical Address Extension)
- mov eax, cr4
- or eax, 1 << 5
- mov cr4, eax
-
- ; set the long mode bit in the EFER MSR (model specific register)
- mov ecx, 0xC0000080
- rdmsr
- or eax, 1 << 8
- wrmsr
-
- ; enable paging in the cr0 register
- mov eax, cr0
- or eax, 1 << 31
- mov cr0, eax
-
- ret
-
-section .bss
-align 4096
-p4_table:
- resb 4096
-p3_table:
- resb 4096
-p2_table:
- resb 4096
-stack_bottom:
- resb 64
-stack_top:
-
-section .rodata
-gdt64:
- dq 0 ; zero entry
-.code: equ $ - gdt64
- dq (1<<43) | (1<<44) | (1<<47) | (1<<53) ; code segment
-.pointer:
- dw $ - gdt64 - 1
- dq gdt64
diff --git a/src/arch/x86_64/grub.cfg b/src/arch/x86_64/grub.cfg
deleted file mode 100644
index 7c34c9c..0000000
--- a/src/arch/x86_64/grub.cfg
+++ /dev/null
@@ -1,7 +0,0 @@
-set timeout=0
-set default=0
-
-menuentry "ats-os" {
- multiboot2 /boot/kernel.bin
- boot
-}
diff --git a/src/arch/x86_64/linker.ld b/src/arch/x86_64/linker.ld
deleted file mode 100644
index 5d788f1..0000000
--- a/src/arch/x86_64/linker.ld
+++ /dev/null
@@ -1,16 +0,0 @@
-ENTRY(start)
-
-SECTIONS {
- . = 1M;
-
- .boot :
- {
- /* ensure that the multiboot header is at the beginning */
- *(.multiboot_header)
- }
-
- .text :
- {
- *(.text)
- }
-}
diff --git a/src/arch/x86_64/long_mode_init.asm b/src/arch/x86_64/long_mode_init.asm
deleted file mode 100644
index eab3788..0000000
--- a/src/arch/x86_64/long_mode_init.asm
+++ /dev/null
@@ -1,17 +0,0 @@
-global long_mode_start
-
-section .text
-bits 64
-long_mode_start:
- ; load 0 into all data segment registers
- mov ax, 0
- mov ss, ax
- mov ds, ax
- mov es, ax
- mov fs, ax
- mov gs, ax
-
- ; print `OKAY` to screen
- mov rax, 0x2f592f412f4b2f4f
- mov qword [0xb8000], rax
- hlt
diff --git a/src/arch/x86_64/multiboot_header.asm b/src/arch/x86_64/multiboot_header.asm
deleted file mode 100644
index 9a9289c..0000000
--- a/src/arch/x86_64/multiboot_header.asm
+++ /dev/null
@@ -1,15 +0,0 @@
-section .multiboot_header
-header_start:
- dd 0xe85250d6 ; magic number (multiboot 2)
- dd 0 ; architecture 0 (protected mode i386)
- dd header_end - header_start ; header length
- ; checksum
- dd 0x100000000 - (0xe85250d6 + 0 + (header_end - header_start))
-
- ; insert optional multiboot tags here
-
- ; required end tag
- dw 0 ; type
- dw 0 ; flags
- dd 8 ; size
-header_end: