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#include "kernel/kernel.h"
#include "asm_int.h"
#include "asm_pit.h"
#include "driver/mouse.h"
#include "interrupts.h"
#include "asm_x86.h"
/** The size of our interrupts table */
#define INT_MAX 255
/** The interrupt descriptor table */
static struct int_desc
{
uint16_t addrLo;
uint16_t sel;
uint8_t zeros;
uint8_t flags;
uint16_t addrHi;
} idt[INT_MAX];
/** The interrupt descriptor table descriptor */
static struct idt_desc
{
uint16_t size;
uint16_t baseLo;
uint16_t baseHi;
} idtd;
/** Sets a handler for a specific interrupt */
static void int_install_ir(int irq, uint16_t flags, uint16_t sel, void *addr)
{
uint64_t base=(uint32_t)&(*(uint32_t*)addr);
idt[irq].addrLo = base & 0xffff;
idt[irq].addrHi = (base >> 16) & 0xffff;
idt[irq].zeros=0;
idt[irq].flags=flags;
idt[irq].sel=sel;
}
/** Installs the interrupt table */
void int_install()
{
idtd.size=sizeof(struct int_desc)*INT_MAX;
uint32_t addr=(uint32_t)&idt[0];
idtd.baseHi=addr>>16;
idtd.baseLo=0xffff&addr;
__asm__("lidt %0"::"m" (idtd));
}
/*
* Interrupt dispatcher
*
* Remeber that we are inside an interrupt here!
*
*/
uint32_t interrupt_handler(uint32_t esp, uint32_t irq)
{
if(irq==0)asm_pit_tick();
// mouse and kb
if(irq==1 || irq==12 ){
uint32_t in=x86_inb(0x60);
if(irq=1)keyboard_handle(in); // do this in separate thread!
// klog("0x60 in %d",in);
}
// 0x80 - a syscall is coming in
if(irq==128){
uint32_t *stack=esp;
uint32_t eax=stack[11];
uint32_t ebx=stack[8];
uint32_t ecx=stack[10];
uint32_t edx=stack[9];
// klog("syscall: %d (ebx=0x%08X,ecx=0x%08X,edx=0x%08X)",eax,ebx,ecx,edx);
task_syscall(eax,ebx,ecx,edx);
esp=my_scheduler(esp,2); // force scheduling of pid=2 (kernel worker)
}
if(irq==0 || irq==129)esp=my_scheduler(esp,-1); // autoschedule
if(irq==255)kpanic("Unhandled Interrupt!");
return esp;
}
// log helpers //
void errlog(uint32_t error_code)
{
klog("error_code: 0x%08X",error_code);
}
void defklog(uint32_t eip, uint16_t cs, uint32_t flags)
{
klog("eip: 0x%08X",eip);
klog("segment: 0x%08X",cs);
klog("eflags: 0x%08X",flags);
}
void show_error(uint32_t err)
{
klog("interrupt error code: 0x%08x",err);
klog("External Event: %x",err&0b001);
klog("Location: %x",err&0b110);
klog("Selector: %x",err&0b1111111111111000);
}
//
void int_default()
{
klog("default handler");
kpanic("unhandled interrupt (is this a panic or should just iognore?)");
}
void exception_handle_0(){ kpanic("Divide by 0"); }
void exception_handle_1(){ kpanic("Single step (debugger)"); }
void exception_handle_2(){ kpanic("Non Maskable Interrupt"); }
void exception_handle_3(){ kpanic("Breakpoint (debugger)"); }
void exception_handle_4(){ kpanic("Overflow"); }
void exception_handle_5(){ kpanic("Bounds check"); }
void exception_handle_6(){ kpanic("Undefined OP Code"); }
void exception_handle_7(){ kpanic("No coprocessor"); }
void exception_handle_8(){ kpanic("Double Fault"); }
void exception_handle_9(){ kpanic("Coprocessor Segment Overrun"); }
void exception_handle_10(){ kpanic("Invalid TSS"); }
void exception_handle_11(){ kpanic("Segment Not Present"); }
void exception_handle_12(){ kpanic("Stack Segment Overrun"); }
void exception_handle_13(uint32_t error_code,uint32_t eip,uint16_t cs,uint16_t unused, uint32_t flags)
{
errlog(error_code);
defklog(eip,cs,flags);
kpanic("Exception: Fault: General Protection Fault");
}
void exception_handle_14(uint32_t error_code,uint32_t eip,uint16_t cs,uint16_t unused, uint32_t flags)
{
errlog(error_code);
klog("error_code_P: %d",error_code&1?1:0);
klog("error_code_W/R: %d",error_code&2?1:0);
klog("error_code_U/S: %d",error_code&4?1:0);
klog("error_code_RSVD: %d",error_code&8?1:0);
klog("error_code_I/D: %d",error_code&16?1:0);
klog("at addr: 0x%08X",x86_get_cr(2));
defklog(eip,cs,flags);
kpanic("Exception: Fault: Page Fault");
}
void exception_handle_15(){ kpanic("Unassigned"); }
void exception_handle_16(){ kpanic("Coprocessor error"); }
void exception_handle_17(){ kpanic("Alignment Check"); }
void exception_handle_18(){ kpanic("Machine Check"); }
// set default handler for all interrupts for a start
void interrupts_init(uint16_t sel)
{
// Setup PIC
klog("setting up PIC",&idt,&idtd);
asm_pic_setup();
klog("initializing. IDT: 0x%08x, IDTD: 0x%08X",&idt,&idtd);
// Default interrupt handling
for(int i=0; i<INT_MAX; i++)
{
int_install_ir(i, 0b10001110, sel,&int255);
}
// Exceptions
int_install_ir(0, 0b10001110, 0x08,&exc0);
int_install_ir(1, 0b10001110, 0x08,&exc1);
int_install_ir(2, 0b10001110, 0x08,&exc2);
int_install_ir(3, 0b10001110, 0x08,&exc3);
int_install_ir(4, 0b10001110, 0x08,&exc4);
int_install_ir(5, 0b10001110, 0x08,&exc5);
int_install_ir(6, 0b10001110, 0x08,&exc6);
int_install_ir(7, 0b10001110, 0x08,&exc7);
int_install_ir(8, 0b10001110, 0x08,&exc8);
int_install_ir(9, 0b10001110, 0x08,&exc9);
int_install_ir(10, 0b10001110, 0x08,&exc10);
int_install_ir(11, 0b10001110, 0x08,&exc11);
int_install_ir(12, 0b10001110, 0x08,&exc12);
int_install_ir(13, 0b10001110, 0x08,&exc13);
int_install_ir(14, 0b10001110, 0x08,&exc14);
int_install_ir(15, 0b10001110, 0x08,&exc15);
int_install_ir(16, 0b10001110, 0x08,&exc16);
int_install_ir(17, 0b10001110, 0x08,&exc17);
int_install_ir(18, 0b10001110, 0x08,&exc18);
// Custom interrupts (hardcoded)
// remember that we shifted all interrupts with the pic by 32
// PIT interrupt handler (irq 0 => 32)
int_install_ir(32, 0b10001110, 0x08,&int0);
// Keyboard interrupt handler (irq 1 => 33)
int_install_ir(33, 0b10001110, 0x08,&int1);
// Mouse interrupt handler (irq 12 => 34)
int_install_ir(44, 0b10001110, 0x08,&int12);
// System Calls / they can be called from ring3 (0b11)
int_install_ir(0x80, 0b11101110, 0x08,&int128);
// Wake Scheduler
int_install_ir(0x81, 0b11101110, 0x08,&int129);
// install IVT
int_install();
}
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