X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86_64%2Fstart64.asm;h=b63b63ac13b50fbeb87e0cae79a2ed648b2b44f9;hb=6d5880d56afb2c6a900e480c891fb40e05457ea3;hp=e69de29bb2d1d6434b8b29ae775ad8c2e48c5391;hpb=302b755a1a7b1d607774353b908e325e934aacdc;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86_64/start64.asm b/Kernel/arch/x86_64/start64.asm
index e69de29b..b63b63ac 100644
--- a/Kernel/arch/x86_64/start64.asm
+++ b/Kernel/arch/x86_64/start64.asm
@@ -0,0 +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
+	mov edi, [gMultibootMagic - KERNEL_BASE]
+	mov esi, [gMultibootPtr - KERNEL_BASE]
+	call kmain
+	
+	cli
+.hlt:
+	hlt
+	jmp .hlt
+
+[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	(5+2+16+2)*8	; IRET, ErrorNum, ErrorCode, GPRs, FS&GS
+[global Proc_ReturnToUser]
+Proc_ReturnToUser:
+	; 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, [rsi-0x20]	; Get user SP
+	xor eax, eax
+	mov [rcx-16], rax
+	sub rcx, 16
+	
+	; Drop down to user mode
+	cli
+	mov rsp, rcx	; Set SP
+	mov rcx, rdi	; SYSRET IP
+	
+	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
+	
+	mov r11, rsi	; NArgs
+	mov r10, rdx	; Args
+
+	; 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
+
+.call:
+	mov rax, [rbp+2*8]	; Ptr
+	call rax
+	
+	pop r11
+	pop r10
+	
+	lea rsp, [rbp]
+	pop rbp
+	ret
+
+; vim: ft=nasm