From c6061d381c0af2dcc7c971347d036dc17399887a Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Thu, 27 May 2010 21:02:51 +0800
Subject: [PATCH] Working on 64-bit IDT

---
 Kernel/Makefile.BuildNum       |  2 +-
 Kernel/arch/x86/main.c         |  2 +-
 Kernel/arch/x86_64/desctab.asm | 99 ++++++++++++++++++++++++++++++++--
 Kernel/arch/x86_64/main.c      | 12 +++++
 Kernel/arch/x86_64/start64.asm |  4 ++
 5 files changed, 113 insertions(+), 6 deletions(-)

diff --git a/Kernel/Makefile.BuildNum b/Kernel/Makefile.BuildNum
index 165c6a4b..20bdebc4 100644
--- a/Kernel/Makefile.BuildNum
+++ b/Kernel/Makefile.BuildNum
@@ -1 +1 @@
-BUILD_NUM = 2212
+BUILD_NUM = 2216
diff --git a/Kernel/arch/x86/main.c b/Kernel/arch/x86/main.c
index 6baec034..34cc4146 100644
--- a/Kernel/arch/x86/main.c
+++ b/Kernel/arch/x86/main.c
@@ -50,7 +50,7 @@ int kmain(Uint MbMagic, void *MbInfoPtr)
 	
 	// Set up non-boot info dependent stuff
 	Desctab_Install();	// Set up GDT and IDT
-	MM_PreinitVirtual();	// Initialise vital mappings
+	MM_PreinitVirtual();	// Initialise virtual mappings
 	
 	switch(MbMagic)
 	{
diff --git a/Kernel/arch/x86_64/desctab.asm b/Kernel/arch/x86_64/desctab.asm
index de606ea6..05e283d6 100644
--- a/Kernel/arch/x86_64/desctab.asm
+++ b/Kernel/arch/x86_64/desctab.asm
@@ -47,8 +47,53 @@ MM_LOCALAPIC	equ	0xFFFFFD0000000000
 %endmacro
 
 [section .text]
+[global Desctab_Init]
 Desctab_Init:
-	; Install IRQ Handlers
+	; Install IDT
+	mov rax, gIDTPtr
+	lidt [rax]
+	
+	; Save to make following instructions smaller
+	mov rdi, gIDT
+	
+	; Set an IDT entry to a callback
+	%macro SETIDT 2
+	mov rax, %2
+	mov	WORD [rdi + %1*16], ax
+	shr rax, 16
+	mov	WORD [rdi + %1*16+6], ax
+	shr rax, 16
+	mov DWORD [rdi+%1*16+8], eax
+	; Enable
+	mov	ax, WORD [rdi + %1*16 + 4]
+	or ax, 0x8000
+	mov	WORD [rdi + %1*16 + 4], ax
+	%endmacro
+	
+	; Install error handlers
+	%macro SETISR 1
+	SETIDT %1, Isr%1
+	%endmacro
+	
+	%assign i 0
+	%rep 32
+	SETISR i
+	%assign i i+1
+	%endrep
+	
+	; Install IRQs
+	%macro SETIRQ 2
+	SETIDT %2, Irq%1
+	%endmacro
+	
+	%assign i 0
+	%rep 16
+	SETIRQ i, 0xF0+i
+	%assign i i+1
+	%endrep
+	
+	; Remap PIC
+	
 	ret
 
 ; int IRQ_AddHandler(int IRQ, void (*Handler)(int IRQ))
@@ -94,18 +139,55 @@ IRQ_AddHandler:
 .ret:
 	ret
 
-%macro DEFERR	1
+%macro ISR_NOERRNO	1
 Isr%1:
 	push	0
 	push	%1
 	jmp	ErrorCommon
 %endmacro
-%macro DEFERRNO	1
+%macro ISR_ERRNO	1
 Isr%1:
 	push	%1
 	jmp	ErrorCommon
 %endmacro
 
+ISR_NOERRNO	0;  0: Divide By Zero Exception
+ISR_NOERRNO	1;  1: Debug Exception
+ISR_NOERRNO	2;  2: Non Maskable Interrupt Exception
+ISR_NOERRNO	3;  3: Int 3 Exception
+ISR_NOERRNO	4;  4: INTO Exception
+ISR_NOERRNO	5;  5: Out of Bounds Exception
+ISR_NOERRNO	6;  6: Invalid Opcode Exception
+ISR_NOERRNO	7;  7: Coprocessor Not Available Exception
+ISR_ERRNO	8;  8: Double Fault Exception (With Error Code!)
+ISR_NOERRNO	9;  9: Coprocessor Segment Overrun Exception
+ISR_ERRNO	10; 10: Bad TSS Exception (With Error Code!)
+ISR_ERRNO	11; 11: Segment Not Present Exception (With Error Code!)
+ISR_ERRNO	12; 12: Stack Fault Exception (With Error Code!)
+ISR_ERRNO	13; 13: General Protection Fault Exception (With Error Code!)
+ISR_ERRNO	14; 14: Page Fault Exception (With Error Code!)
+ISR_NOERRNO	15; 15: Reserved Exception
+ISR_NOERRNO	16; 16: Floating Point Exception
+ISR_NOERRNO	17; 17: Alignment Check Exception
+ISR_NOERRNO	18; 18: Machine Check Exception
+ISR_NOERRNO	19; 19: Reserved
+ISR_NOERRNO	20; 20: Reserved
+ISR_NOERRNO	21; 21: Reserved
+ISR_NOERRNO	22; 22: Reserved
+ISR_NOERRNO	23; 23: Reserved
+ISR_NOERRNO	24; 24: Reserved
+ISR_NOERRNO	25; 25: Reserved
+ISR_NOERRNO	26; 26: Reserved
+ISR_NOERRNO	27; 27: Reserved
+ISR_NOERRNO	28; 28: Reserved
+ISR_NOERRNO	29; 29: Reserved
+ISR_NOERRNO	30; 30: Reserved
+ISR_NOERRNO	31; 31: Reserved
+
+ErrorCommon:
+	add rsp, 2*8
+	iret
+
 %macro DEFIRQ	1
 Irq%1:
 	push	0
@@ -113,6 +195,12 @@ Irq%1:
 	jmp	IrqCommon
 %endmacro
 
+%assign i 0
+%rep 16
+DEFIRQ	i
+%assign i i+1
+%endrep
+
 IrqCommon:
 	PUSH_GPR
 	
@@ -166,7 +254,10 @@ SchedulerIRQ:
 
 [section .data]
 gIDT:
-	times 256	dw	0x00080000, 0x00008E00, 0, 0	; 64-bit Interrupt Gate, CS = 0x8, IST0
+	times 256	dd	0x00080000, 0x00008E00, 0, 0	; 64-bit Interrupt Gate, CS = 0x8, IST0
+gIDTPtr:
+	dw	256*16-1
+	dq	gIDT
 
 gaIRQ_Handlers:
 	times	16*NUM_IRQ_CALLBACKS	dq	0
diff --git a/Kernel/arch/x86_64/main.c b/Kernel/arch/x86_64/main.c
index 60d5cf08..6a1520a2 100644
--- a/Kernel/arch/x86_64/main.c
+++ b/Kernel/arch/x86_64/main.c
@@ -3,12 +3,24 @@
  */
 #include <acess.h>
 
+// === IMPORTS ===
+extern void	Desctab_Init(void);
+extern void	MM_InitVirt(void);
+
+// === PROTOTYPES ===
+
 // === GLOBALS ==
 
 // === CODE ===
 void kmain(Uint MbMagic, void *MbInfoPtr)
 {
+	*(Uint16*)(0xB8000) = 0x1F00|'A';
+	
+	Desctab_Init();
+	MM_InitVirt();
 	
+	for(;;)
+		__asm__ __volatile__ ("hlt");
 }
 
 void Arch_LoadBootModules(void)
diff --git a/Kernel/arch/x86_64/start64.asm b/Kernel/arch/x86_64/start64.asm
index 699c7931..c98afdbd 100644
--- a/Kernel/arch/x86_64/start64.asm
+++ b/Kernel/arch/x86_64/start64.asm
@@ -3,6 +3,8 @@
 ;
 [bits 64]
 
+[extern kmain]
+
 [section .text]
 [global start64]
 start64:
@@ -28,6 +30,8 @@ start64:
 	mov rsp, gInitialKernelStack
 	
 	; Call main
+	call kmain
+	
 	cli
 .hlt:
 	hlt
-- 
2.20.1