[WIP] Interrupts

kernel/Makefile

@@ -29,8 +29,7 @@ LIBS:=$(LIBS) $(KERNEL_ARCH_LIBS)
 
 KERNEL_OBJS=\
 $(KERNEL_ARCH_OBJS) \
-kernel/kernel.o \
-gdt/gdt.o
+kernel/kernel.o 
 
 OBJS=\
 $(ARCHDIR)/crti.o \
@@ -66,11 +65,16 @@ $(ARCHDIR)/crtbegin.o $(ARCHDIR)/crtend.o:
 .S.o:
 	$(CC) -MD -c $< -o $@ $(CFLAGS) $(CPPFLAGS)
 
+%.o: %.asm
+	nasm -f elf  $< -o  $@
+
+
 clean:
 	rm -f myos.kernel
 	rm -f $(OBJS) *.o */*.o */*/*.o
 	rm -f $(OBJS:.o=.d) *.d */*.d */*/*.d
-
+	rm -f ${ARCHDIR} *.o */*.o */*/*/*.o
+	rm -f kernel/kernel/ *.d *.o
 install: install-headers install-kernel
 
 install-headers:

kernel/arch/i386/boot.S

@@ -19,6 +19,7 @@ stack_bottom:
 .skip 16384
 stack_top:
 
+
 #kernel entry point
 .section .text
 .global _start
@@ -33,7 +34,6 @@ _start:
     mov %ax, %fs
     mov %ax, %gs
     call kernel_main
-    cli
 1: hlt
     jmp 1b
 

kernel/arch/i386/make.config

@@ -6,4 +6,5 @@ KERNEL_ARCH_LIBS=
 KERNEL_ARCH_OBJS=\
 $(ARCHDIR)/boot.o \
 $(ARCHDIR)/tty.o \
-
+${ARCHDIR}/x86_int.o \
+${ARCHDIR}/x86.o \

kernel/arch/i386/x86.c

@@ -0,0 +1,155 @@
+#include<string.h>
+#include<arch/i386/x86.h>
+#include<stdio.h>
+struct gdtdesc kgdt[5];
+struct gdtr kgdtr;
+struct idtr kidtr;
+struct idtdesc kidt[256];
+uint8_t stack[STACKSIZE];
+
+
+void read_gdtr(uint32_t* tgdtr) {
+    asm("sgdt %0" : "=m" (*tgdtr));
+}
+
+void load_gdt(struct gdtr *gdtr) {
+	asm volatile("lgdt %0" : : "m" (*gdtr));
+}
+
+void load_idt(struct idtr *idtr) {
+	asm volatile("lidt %0" : : "m" (*idtr));
+}
+
+void gdt_init(void) {
+
+	create_gdt_descriptor(0x0, 0x0, 0x0, 0x0, &kgdt[0]);
+	create_gdt_descriptor(0x0, 0xFFFF, 0x9A, 0xCF, &kgdt[1]);
+	create_gdt_descriptor(0x0, 0xFFFF, 0x92, 0xCF, &kgdt[2]);
+	create_gdt_descriptor(0x0, 0xFFFF, 0xFA, 0xCF, &kgdt[3]);
+	create_gdt_descriptor(0x0, 0xFFFF, 0xF2, 0xCF, &kgdt[4]);
+//    	create_gdt_descriptor(0x0, 0xFFFF, 0xF2, 0xCF, &kgdt[5]);
+//	create_gdt_descriptor(0x0, 0x0, 0xF7, 0x0D, &kgdt[6]);
+	kgdtr.limit = sizeof(kgdt) -1;
+	kgdtr.base = (uint32_t)&kgdt;
+
+	load_gdt(&kgdtr);
+}
+
+void create_gdt_descriptor(uint32_t base, uint32_t limit, uint8_t access, uint8_t flags, struct gdtdesc *desc) {
+	if (desc == NULL) {
+		printf("NULL");
+	}
+	desc->limit0_15 = (limit & 0xFFFF);
+	desc->base0_15 = (base & 0xFFFF);
+	desc->base16_23 = (base & 0xFF) >> 16;
+	desc->access_bytes = access;
+	desc->limit16_19 = (limit & 0xF) >> 16;
+	desc->flags = (flags & 0xF);
+	return;
+}
+
+void create_idt_descriptor(uint16_t select, uint32_t offset, uint8_t type, struct idtdesc * desc) {
+	printf("select: %d, offset: %d, type: %d\n", select, offset, type);
+	desc->offset0_15 = (offset & 0xFFFF);
+	desc->select = select;
+	desc->access_gran = type;
+	desc->alwaysZero = 0;
+	desc->offset16_31 = (offset & 0xFFFF0000) >> 16;
+	return;
+}
+
+extern void _asm_int_0();
+extern void _asm_int_1();
+extern void isr0();
+
+void outb(uint32_t ad, uint8_t v)
+{
+	asm volatile("outb %%al, %%dx" :: "d" (ad), "a" (v));
+}
+
+uint8_t inb(uint32_t ad)
+{
+	uint8_t v; 
+	asm volatile("inb %%dx, %%al" : "=a" (v) : "d" (ad)); 
+	return v;
+}
+
+void isr_default_int(int id)
+{
+	printf("default int %d", id);
+	asm volatile("hlt");
+}
+
+void init_pic(void)
+{
+	outb(0x20, 0x11);
+	outb(0xA0, 0x11);
+
+	outb(0x21, 0x20);
+	outb(0xA1, 0x28);
+
+	outb(0x21, 0x04);
+	outb(0xA1, 0x02);
+
+	outb(0x21, 0x01);
+	outb(0xA1, 0x01);
+
+	outb(0x21, 0x0);
+	outb(0xA1, 0x0);
+	printf("PIC initialised\n");
+}
+
+
+extern void idt_load();
+
+void init_idt(void) {
+
+	kidtr.limit = (sizeof(struct idtdesc) * 256) - 1;
+	kidtr.base = (uint32_t)&kidt;
+	//memset(&kidt, 0, sizeof(struct idtdesc) * 256);
+//	idt_load();
+	load_idt(&kidtr);
+	printf("IDT initialized\n");
+}
+
+struct regs{
+    unsigned int gs, fs, es, ds;      /* pushed the segs last */
+    unsigned int edi, esi, ebp, esp, ebx, edx, ecx, eax;  /* pushed by 'pusha' */
+    unsigned int int_no, err_code;    /* our 'push byte #' and ecodes do this */
+    unsigned int eip, cs, eflags, useresp, ss;   /* pushed by the processor automatically */ 
+};
+
+void *irq_routines[16] ={
+    0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0
+};
+
+void fault_handler(struct regs *r)
+{
+	printf("ERROR everywhere\n");
+    	/* Is this a fault whose number is from 0 to 31? */
+    if (r->int_no < 32)
+    {
+	    printf("ERROR here\n");
+	    asm("hlt");
+//        bsodmsg(exception_messages[r->int_no]);
+    } else {
+	    printf("ERROR there\n");
+	    asm("hlt");
+    }
+}
+
+void irq_install_handler(int irq, void (*handler)(struct regs *r)){
+    irq_routines[irq] = handler;
+}
+
+void setup_isr(void) {
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[0]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[1]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[2]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[3]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[4]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[5]);
+	create_idt_descriptor(0x08, (uint32_t)isr0, INTGATE, &kidt[6]);
+}
+

kernel/arch/i386/x86_int.asm

@@ -0,0 +1,177 @@
+
+global idt_load
+extern kidtr
+idt_load:
+    lidt [kidtr]
+    ret
+
+global isr0
+global isr1
+global isr2
+global isr3
+global isr4
+global isr5
+global isr6
+global isr7
+global isr8
+global isr9
+global isr10
+global isr11
+global isr12
+global isr13
+global isr14
+global isr15
+global isr16
+global isr17
+global isr18
+global isr19
+global isr20
+global isr21
+global isr22
+global isr23
+global isr24
+global isr25
+global isr26
+global isr27
+global isr28
+global isr29
+global isr30
+global isr31
+
+%macro ISR_NOCODE 1
+	isr%1:
+		cli
+		push byte 0
+		push byte %1
+		jmp isr_common_stub
+%endmacro
+
+%macro ISR_CODE 1
+	isr%1:
+		cli
+		push byte %1
+		jmp isr_common_stub
+%endmacro
+
+
+;Divide By Zero Exception
+ISR_NOCODE 0
+
+;Debug Exception
+ISR_NOCODE 1
+
+;Non Maskable Interrrupt Exception
+ISR_NOCODE 2
+
+;Breakpoint Exception
+ISR_NOCODE 3
+
+;Into Detected Overflow Exception
+ISR_NOCODE 4
+
+;Out of Bounds Exception
+ISR_NOCODE 5
+
+;Invalid Opcode Exception
+ISR_NOCODE 6
+
+;No Coprocessor Exception
+ISR_NOCODE 7
+
+;Double Fault Exception
+ISR_CODE 8
+
+;Coprocessor Segment Overrun Exception
+ISR_NOCODE 9
+
+;Bad TSS Exception
+ISR_CODE 10
+
+;Segment Not Present Exception
+ISR_CODE 11
+
+;Stack Fault Exception
+ISR_CODE 12
+
+;General Protection Fault Exception
+ISR_CODE 13
+
+;Page Fault Exception
+ISR_CODE 14
+
+;Unknown Interrupt Exception
+ISR_NOCODE 15
+
+;Coprocessor Fault Exception
+ISR_NOCODE 16
+
+;Alignment Check Exception
+ISR_NOCODE 17
+
+;Machine Check Exception
+ISR_NOCODE 18
+
+;Reserved
+ISR_NOCODE 19
+
+;Reserved
+ISR_NOCODE 20
+
+;Reserved
+ISR_NOCODE 21
+
+;Reserved
+ISR_NOCODE 22
+
+;Reserved
+ISR_NOCODE 23
+
+;Reserved
+ISR_NOCODE 24
+
+;Reserved
+ISR_NOCODE 25
+
+;Reserved
+ISR_NOCODE 26
+
+;Reserved
+ISR_NOCODE 27
+
+;Reserved
+ISR_NOCODE 28
+
+;Reserved
+ISR_NOCODE 29
+
+;Reserved
+ISR_NOCODE 30
+
+;Reserved
+ISR_NOCODE 31
+
+extern fault_handler
+isr_common_stub:
+    pusha
+    push ds
+    push es
+    push fs
+    push gs
+    mov ax, 0x10   ; Load the Kernel Data Segment descriptor!
+    mov ds, ax
+    mov es, ax
+    mov fs, ax
+    mov gs, ax
+    mov eax, esp   ; Push us the stack
+    push eax
+    mov eax, fault_handler
+    call eax       ; A special call, preserves the 'eip' register
+    pop eax
+    pop gs
+    pop fs
+    pop es
+    pop ds
+    popa
+    add esp, 8     ; Cleans up the pushed error code and pushed ISR number
+    iret           ; pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP!
+