New kernel stack, fixing pmem alloc bug, updated to maintain free page positions

[tpg/acess2.git] / Kernel / arch / x86_64 / start64.asm

diff --git a/Kernel/arch/x86_64/start64.asm b/Kernel/arch/x86_64/start64.asm
index a2ffb19..33c77d6 100644 (file)
--- a/Kernel/arch/x86_64/start64.asm
+++ b/Kernel/arch/x86_64/start64.asm
@@ -2,13 +2,46 @@
 ; Acess2 x86_64 Port
 ;
 [bits 64]
+KERNEL_BASE    equ     0xFFFF800000000000
+
+[extern kmain]
+
+[extern gMultibootPtr]
+[extern gMultibootMagic]
 
 [section .text]
 [global start64]
 start64:
+       ; Load Registers
+       mov ax, 0x10
+       mov ds, ax
+       mov es, ax
+       mov fs, ax
+       mov gs, ax
+       
+       ; Go to high memory
+       mov rax, start64.himem
+       jmp rax
+.himem:
+       
+       ; Clear the screen
+       mov rax, 0x1F201F201F201F20     ; Set the screen to White on blue, space (4 characters)
+       mov edi, 0xB8000
+       mov ecx, 80*25*2/8
+       rep stosq
+       
        ; Set kernel stack
+       mov rsp, gInitialKernelStack
+       
        ; Call main
-       jmp $
+       mov edi, [gMultibootMagic - KERNEL_BASE]
+       mov esi, [gMultibootPtr - KERNEL_BASE]
+       call kmain
+       
+       cli
+.hlt:
+       hlt
+       jmp .hlt
 
 [global GetRIP]
 GetRIP:
@@ -17,10 +50,10 @@ GetRIP:
 
 [global GetCPUNum]
 GetCPUNum:
-       str ax
-       mov gs, ax
        xor rax, rax
-       mov al, [gs:104]        ; End of TSS
+       str ax
+       sub ax, 0x38    ; TSS Base
+       shr ax, 4       ; One 16-byte TSS per CPU
        ret
 
 KSTACK_USERSTATE_SIZE  equ     (16+1+5)*8      ; GPRegs, CPU, IRET
@@ -94,6 +127,6 @@ User_Syscall_Exit:
 
 [section .bss]
 [global gInitialKernelStack]
-       resd    1024*1  ; 1 Page
+       resd    1024*4  ; 4 Pages
 gInitialKernelStack: