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, void *);
  13
  14 // === PROTOTYPES ===
  15 void    IRQ_Handler(tRegs *Regs);
  16
  17 // === GLOBALS ===
  18 tIRQ_Callback   gIRQ_Handlers[16][MAX_CALLBACKS_PER_IRQ];
  19 void    *gaIRQ_DataPointers[16][MAX_CALLBACKS_PER_IRQ];
  20
  21 // === CODE ===
  22 /**
  23  * \fn void IRQ_Handler(tRegs *Regs)
  24  * \brief Handle an IRQ
  25  */
  26 void IRQ_Handler(tRegs *Regs)
  27 {
  28          int    irq = Regs->int_num - 0xF0;
  29          int    bHandled = 0;
  30
  31         //Log("IRQ_Handler: (Regs={int_num:%i})", Regs->int_num);
  32
  33         for( int i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  34         {
  35                 if( gIRQ_Handlers[irq][i] ) {
  36                         gIRQ_Handlers[irq][i](irq, gaIRQ_DataPointers[irq][i]);
  37                         #if TRACE_IRQS
  38                         if( irq != 8 )
  39                                 Log("IRQ %i: Call %p", Regs->int_num, gIRQ_Handlers[Regs->int_num][i]);
  40                         #endif
  41                         bHandled = 1;
  42                 }
  43         }
  44
  45         if( !bHandled ) {
  46                 Log_Debug("IRQ", "Unhandled IRQ %i", irq);
  47         }
  48
  49         //Log(" IRQ_Handler: Resetting");
  50         if(irq >= 8)
  51                 outb(0xA0, 0x20);       // ACK IRQ (Secondary PIC)
  52         outb(0x20, 0x20);       // ACK IRQ
  53         //Log("IRQ_Handler: RETURN");
  54 }
  55
  56 /**
  57  * \fn int IRQ_AddHandler( int Num, void (*Callback)(int) )
  58  */
  59 int IRQ_AddHandler( int Num, void (*Callback)(int, void*), void *Ptr )
  60 {
  61         for( int i = 0; i < MAX_CALLBACKS_PER_IRQ; i++ )
  62         {
  63                 if( gIRQ_Handlers[Num][i] == NULL )
  64                 {
  65                         //Log_Log("IRQ", "Added IRQ%i Cb#%i %p", Num, i, Callback);
  66                         gIRQ_Handlers[Num][i] = Callback;
  67                         gaIRQ_DataPointers[Num][i] = Ptr;
  68                         return Num * MAX_CALLBACKS_PER_IRQ + i;
  69                 }
  70         }
  71
  72         Log_Warning("IRQ", "No free callbacks on IRQ%i", Num);
  73         return -1;
  74 }
  75
  76 void IRQ_RemHandler(int Handle)
  77 {
  78          int    Num = Handle / MAX_CALLBACKS_PER_IRQ;
  79          int    id = Handle % MAX_CALLBACKS_PER_IRQ;
  80         gIRQ_Handlers[Num][id] = NULL;
  81 }