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Add and setup a P4 and a P3 table

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Philipp Oppermann
2015-08-13 13:14:33 +02:00
parent bd11ed9a6f
commit b47699685f
1 changed files with 18 additions and 0 deletions
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18
src/arch/x86_64/boot.asm
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@@ -23,10 +23,23 @@ start:
call check_cpuid call check_cpuid
call check_long_mode call check_long_mode
call setup_page_tables
; print `OK` to screen ; print `OK` to screen
mov dword [0xb8000], 0x2f4b2f4f mov dword [0xb8000], 0x2f4b2f4f
hlt hlt
setup_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 a huge page that starts at address 0
mov dword [p3_table], 0b10000011 ; present + writable + huge
ret
; Prints `ERR: ` and the given error code to screen and hangs. ; Prints `ERR: ` and the given error code to screen and hangs.
; parameter: error code (in ascii) in al ; parameter: error code (in ascii) in al
error: error:
@@ -80,6 +93,11 @@ check_long_mode:
jmp error jmp error
section .bss section .bss
align 4096
p4_table:
resb 4096
p3_table:
resb 4096
stack_bottom: stack_bottom:
resb 64 resb 64
stack_top: stack_top: