1998/0910/pc/i8259.c (diff list | history)

1998/0320/sys/src/9/pc/i8259.c:27,46 – 1998/0910/sys/src/9/pc/i8259.c:27,47 (short | long | prev | next)
XXX bug fix?: add i8259lock. Change Vector* to Irq*. rsc Fri Mar 4 12:44:25 2005
1997/0327		static int int0mask; /* interrupts enabled for first 8259 */ static int int1mask; /* interrupts enabled for second 8259 */
1998/0910		static int elcr; /* mask of level-triggered interrupts */ static Lock i8259lock;
1997/0327		int elcr; /* mask of level-triggered interrupts */                  void i8259init(void) { int elcr1;
1998/0910		ilock(&i8259lock);
1997/0327		int0mask = 0xFF; int1mask = 0xFF; /* * Set up the first 8259 interrupt processor. * Make 8259 interrupts start at CPU vector Int0vec.
1998/0910		* Make 8259 interrupts start at CPU vector VectorPIC.
1997/0327		* Set the 8259 as master with edge triggered * input with fully nested interrupts. */
1998/0320/sys/src/9/pc/i8259.c:91,149 – 1998/0910/sys/src/9/pc/i8259.c:92,158
1997/0327		elcr = (inb(Elcr2)<<8)|elcr1; } outb(Elcr1, elcr1);
1998/0910		iunlock(&i8259lock);
1997/0521		// if(elcr) // print("ELCR: %4.4uX\n", elcr);
1997/0327		} int i8259isr(int v)
1998/0910		i8259isr(int vno)
1997/0327		{ int isr;
1998/0910		if(vno < VectorPIC || vno > VectorPIC+MaxIrqPIC) return 0;
1997/0327		/* * tell the 8259 that we're done with the * highest level interrupt (interrupts are still * off at this point) */ isr = 0; if(v >= VectorPIC && v <= MaxVectorPIC){ isr = inb(Int0ctl); outb(Int0ctl, EOI); if(v >= VectorPIC+8){ isr |= inb(Int1ctl)<<8; outb(Int1ctl, EOI); }
1998/0910		ilock(&i8259lock); isr = inb(Int0ctl); outb(Int0ctl, EOI); if(vno >= VectorPIC+8){ isr |= inb(Int1ctl)<<8; outb(Int1ctl, EOI);
1997/0327		}
1998/0910		iunlock(&i8259lock);
1997/0327		return isr & (1<<(v-VectorPIC));
1998/0910		return isr & (1<<(vno-VectorPIC));
1997/0327		} int i8259enable(int v, int, Irqctl* irqctl)
1998/0910		i8259enable(Vctl* v)
1997/0327		{
1998/0320		if(v < VectorPIC || v > MaxVectorPIC){ print("i8259enable: vector %d out of range\n", v); return -1; }
1997/0327		v -= VectorPIC;
1998/0910		int irq;
1997/0327		/* * enable corresponding interrupt in 8259
1998/0910		* Given an IRQ, enable the corresponding interrupt in the i8259 * and return the vector to be used. The i8259 is set to use a fixed * range of vectors starting at VectorPIC.
1997/0327		*/ if(v < 8){ int0mask &= ~(1<<v);
1998/0910		irq = v->irq; if(irq < 0 || irq > MaxIrqPIC){ print("i8259enable: irq %d out of range\n", irq); return -1; } ilock(&i8259lock); if(irq < 8){ int0mask &= ~(1<<irq);
1997/0327		outb(Int0aux, int0mask); } else{ int1mask &= ~(1<<(v-8));
1998/0910		int1mask &= ~(1<<(irq-8));
1997/0327		outb(Int1aux, int1mask); } if(elcr & (1<<v)) irqctl->eoi = i8259isr;
1998/0910		if(elcr & (1<<irq)) v->eoi = i8259isr;
1997/0327		else irqctl->isr = i8259isr; irqctl->isintr = 1;
1998/0910		v->isr = i8259isr; iunlock(&i8259lock);
1997/0327		return v;
1998/0910		return VectorPIC+irq;
1997/0327		}