Kernel/arch/x86/irq.c

   1 /*
   2  * AcessOS Microkernel Version
   3  * irq.c
   4  */
   5 #include <acess.h>
   6
   7 // === CONSTANTS ===
   8 #define MAX_CALLBACKS_PER_IRQ   4
   9 #define TRACE_IRQS      0
  10
  11 // === TYPES ===
  12 typedef void (*tIRQ_Callback)(int);
  13
  14 // === GLOBALS ===
  15 tIRQ_Callback   gIRQ_Handlers[16][MAX_CALLBACKS_PER_IRQ];
  16
  17 // === CODE ===
  18 /**
  19  * \fn void IRQ_Handler(tRegs *Regs)
  20  * \brief Handle an IRQ
  21  */
  22 void IRQ_Handler(tRegs *Regs)
  23 {
  24          int    i;
  25
  26         Regs->int_num -= 0xF0;  // Adjust
  27
  28         //Log("IRQ_Handler: (Regs={int_num:%i})", Regs->int_num);
  29
  30         for( i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  31         {
  32                 if( gIRQ_Handlers[Regs->int_num][i] ) {
  33                         gIRQ_Handlers[Regs->int_num][i](Regs->int_num);
  34                         #if TRACE_IRQS
  35                         if( Regs->int_num != 8 )
  36                                 Log("IRQ %i: Call %p", Regs->int_num, gIRQ_Handlers[Regs->int_num][i]);
  37                         #endif
  38                 }
  39         }
  40
  41         //Log(" IRQ_Handler: Resetting");
  42         if(Regs->int_num >= 8)
  43                 outb(0xA0, 0x20);       // ACK IRQ (Secondary PIC)
  44         outb(0x20, 0x20);       // ACK IRQ
  45         //Log("IRQ_Handler: RETURN");
  46 }
  47
  48 /**
  49  * \fn int IRQ_AddHandler( int Num, void (*Callback)(int) )
  50  */
  51 int IRQ_AddHandler( int Num, void (*Callback)(int) )
  52 {
  53          int    i;
  54         for( i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  55         {
  56                 if( gIRQ_Handlers[Num][i] == NULL ) {
  57                         Log_Log("IRQ", "Added IRQ%i Cb#%i %p", Num, i, Callback);
  58                         gIRQ_Handlers[Num][i] = Callback;
  59                         return 1;
  60                 }
  61         }
  62
  63         Log_Warning("IRQ", "No free callbacks on IRQ%i", Num);
  64         return 0;
  65 }