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 // === PROTOTYPES ===
  15 void    IRQ_Handler(tRegs *Regs);
  16
  17 // === GLOBALS ===
  18 tIRQ_Callback   gIRQ_Handlers[16][MAX_CALLBACKS_PER_IRQ];
  19
  20 // === CODE ===
  21 /**
  22  * \fn void IRQ_Handler(tRegs *Regs)
  23  * \brief Handle an IRQ
  24  */
  25 void IRQ_Handler(tRegs *Regs)
  26 {
  27          int    i;
  28
  29         Regs->int_num -= 0xF0;  // Adjust
  30
  31         //Log("IRQ_Handler: (Regs={int_num:%i})", Regs->int_num);
  32
  33         for( i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  34         {
  35                 if( gIRQ_Handlers[Regs->int_num][i] ) {
  36                         gIRQ_Handlers[Regs->int_num][i](Regs->int_num);
  37                         #if TRACE_IRQS
  38                         if( Regs->int_num != 8 )
  39                                 Log("IRQ %i: Call %p", Regs->int_num, gIRQ_Handlers[Regs->int_num][i]);
  40                         #endif
  41                 }
  42         }
  43
  44         //Log(" IRQ_Handler: Resetting");
  45         if(Regs->int_num >= 8)
  46                 outb(0xA0, 0x20);       // ACK IRQ (Secondary PIC)
  47         outb(0x20, 0x20);       // ACK IRQ
  48         //Log("IRQ_Handler: RETURN");
  49 }
  50
  51 /**
  52  * \fn int IRQ_AddHandler( int Num, void (*Callback)(int) )
  53  */
  54 int IRQ_AddHandler( int Num, void (*Callback)(int) )
  55 {
  56          int    i;
  57         for( i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  58         {
  59                 if( gIRQ_Handlers[Num][i] == NULL ) {
  60                         Log_Log("IRQ", "Added IRQ%i Cb#%i %p", Num, i, Callback);
  61                         gIRQ_Handlers[Num][i] = Callback;
  62                         return 1;
  63                 }
  64         }
  65
  66         Log_Warning("IRQ", "No free callbacks on IRQ%i", Num);
  67         return 0;
  68 }