Updates to CPU Determining and initialising fractal mappings

[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 e69de29..30fc971 100644 (file)
--- a/Kernel/arch/x86_64/start64.asm
+++ b/Kernel/arch/x86_64/start64.asm
@@ -0,0 +1,79 @@
+;
+; Acess2 x86_64 Port
+;
+[bits 64]
+
+[section .text]
+[global start64]
+start64:
+       ; Set kernel stack
+       ; Call main
+       jmp $
+
+[global GetRIP]
+GetRIP:
+       mov rax, [rsp]
+       ret
+
+[global GetCPUNum]
+GetCPUNum:
+       str ax
+       mov gs, ax
+       xor rax, rax
+       mov al, [gs:104]        ; End of TSS
+       ret
+
+KSTACK_USERSTATE_SIZE  equ     (16+1+5)*8      ; GPRegs, CPU, IRET
+[global Proc_ReturnToUser]
+[extern Proc_GetCurThread]
+Proc_ReturnToUser:
+       ; RBP is the handler to use
+       
+       call Proc_GetCurThread
+       
+       ; EAX is the current thread
+       mov rbx, rax
+       mov rax, [rbx+40]       ; Get Kernel Stack
+       sub rax, KSTACK_USERSTATE_SIZE
+       
+       ;
+       ; NOTE: This can cause corruption if the signal happens while the user
+       ;       has called a kernel operation.
+       ; Good thing this can only be called on a user fault.
+       ;
+       
+       ; Get and alter User SP
+       mov rcx, [rax+KSTACK_USERSTATE_SIZE-3*8]
+       mov rdx, [rbx+60]       ; Get Signal Number
+       mov [rcx-8], rdx
+       mov rax, User_Syscall_RetAndExit
+       mov [rcx-16], rax
+       sub rcx, 16
+       
+       ; Restore Segment Registers
+       mov ax, 0x23
+       mov ds, ax
+       mov es, ax
+       
+       push 0x23       ; SS
+       push rcx        ; RSP
+       push 0x202      ; RFLAGS (IF and Rsvd)
+       push 0x1B       ; CS
+       push rbp        ; RIP
+       
+       iret
+
+[section .usertext]
+User_Syscall_RetAndExit:
+       mov rdi, rax
+       jmp User_Syscall_Exit
+User_Syscall_Exit:
+       xor rax, rax
+       ; RDI: Return Value
+       int 0xAC
+
+[section .bss]
+[global gInitialKernelStack]
+       resd    1024*1  ; 1 Page
+gInitialKernelStack:
+