X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86_64%2Fstart64.asm;h=b63b63ac13b50fbeb87e0cae79a2ed648b2b44f9;hb=6d5880d56afb2c6a900e480c891fb40e05457ea3;hp=c1f1e58be0e474e6308e5676083555b6e8585d44;hpb=9f407c493c33928e0f19b834699d9694036ca42e;p=tpg%2Facess2.git diff --git a/Kernel/arch/x86_64/start64.asm b/Kernel/arch/x86_64/start64.asm index c1f1e58b..b63b63ac 100644 --- a/Kernel/arch/x86_64/start64.asm +++ b/Kernel/arch/x86_64/start64.asm @@ -1,70 +1,146 @@ ; ; Acess2 x86_64 Port ; +%include "arch/x86_64/include/common.inc.asm" [bits 64] +;KERNEL_BASE equ 0xFFFF800000000000 +KERNEL_BASE equ 0xFFFFFFFF80000000 + +[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: + + xor rax, rax + mov dr0, rax ; Set CPU0 + + ; 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, 0xFFFFA00000000000 + INITIAL_KSTACK_SIZE*0x1000 + ; Call main - jmp $ + mov edi, [gMultibootMagic - KERNEL_BASE] + mov esi, [gMultibootPtr - KERNEL_BASE] + call kmain + + cli +.hlt: + hlt + jmp .hlt -[global GetRIP] -GetRIP: - mov rax, [rsp] +[global GetCPUNum] +GetCPUNum: + xor rax, rax + str ax + sub ax, 0x38 ; TSS Base + shr ax, 4 ; One 16-byte TSS per CPU ret -KSTACK_USERSTATE_SIZE equ (4+8+1+5)*4 ; SRegs, GPRegs, CPU, IRET +KSTACK_USERSTATE_SIZE equ (5+2+16+2)*8 ; IRET, ErrorNum, ErrorCode, GPRs, FS&GS [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 + ; RDI - Handler + ; RSI - Kernel Stack + ; RDX - Signal num ; ; 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. ; - + + xchg bx, bx ; 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 QWORD [rcx-16], User_Syscall_RetAndExit + mov rcx, [rsi-0x20] ; Get user SP + xor eax, eax + mov [rcx-16], rax sub rcx, 16 - ; Restore Segment Registers - mov ax, 0x23 - mov ds, ax - mov es, ax + ; Drop down to user mode + cli + mov rsp, rcx ; Set SP + mov rcx, rdi ; SYSRET IP - push 0x23 ; SS - push rcx ; RSP - push 0x202 ; RFLAGS (IF and Rsvd) - push 0x1B ; CS - push rbp ; RIP + mov rdi, rdx ; Argument for handler + mov r11, 0x202 ; RFlags + db 0x48 + sysret + +; int CallWithArgArray(void *Ptr, int NArgs, Uint *Args) +; Call a function passing the array as arguments +[global CallWithArgArray] +CallWithArgArray: + push rbp + mov rbp, rsp + push r10 + push r11 + + mov [rbp+2*8], rdi ; Save Ptr to stack - iret + mov r11, rsi ; NArgs + mov r10, rdx ; Args -[section .usertext] -User_Syscall_RetAndExit: - mov rdi, rax - jmp User_Syscall_Exit -User_Syscall_Exit: - xor rax, rax - ; RDI: Return Value - int 0xAC + ; Arg 1: RDI + mov rdi, [r10] + add r10, 8 + dec r11 + jz .call + ; Arg 2: RSI + mov rsi, [r10] + add r10, 8 + dec r11 + jz .call + ; Arg 3: RDX + mov rdx, [r10] + add r10, 8 + dec r11 + jz .call + ; Arg 4: RCX + mov rcx, [r10] + add r10, 8 + dec r11 + jz .call + ; Arg 5: R8 + mov r8, [r10] + add r10, 8 + dec r11 + jz .call + ; Arg 6: R9 + mov r9, [r10] + add r10, 8 + dec r11 + jz .call + ; No support for more -[section .bss] -[global gInitialKernelStack] - resd 1024*1 ; 1 Page -gInitialKernelStack: +.call: + mov rax, [rbp+2*8] ; Ptr + call rax + + pop r11 + pop r10 + + lea rsp, [rbp] + pop rbp + ret +; vim: ft=nasm