/* Unregister an interrupt handler. */
PUBLIC void rm_irq_handler( const irq_hook_t* hook ) {
const int irq = hook->irq;
const int id = hook->id;
irq_hook_t **line;
if( irq < 0 || irq >= NR_IRQ_VECTORS )
panic("invalid call to rm_irq_handler: %d", irq);
/* remove the hook */
line = &irq_handlers[irq];
while( (*line) != NULL ) {
if((*line)->id == id) {
(*line) = (*line)->next;
if (irq_actids[irq] & id)
irq_actids[irq] &= ~id;
}
else {
line = &(*line)->next;
}
}
/* Disable the irq if there are no other handlers registered.
* If the irq is shared, reenable it if there is no active handler.
*/
if (irq_handlers[irq] == NULL) {
hw_intr_mask(irq);
hw_intr_not_used(irq);
}
else if (irq_actids[irq] == 0) {
hw_intr_unmask(irq);
}
}
/*
* The function first disables interrupt is need be and restores the state at
* the end. Before returning, it unmasks the IRQ if and only if all active ID
* bits are cleared, and restart a process.
*/
PUBLIC void irq_handle(int irq)
{
irq_hook_t * hook;
/* here we need not to get this IRQ until all the handlers had a say */
hw_intr_mask(irq);
hook = irq_handlers[irq];
/* Call list of handlers for an IRQ. */
while( hook != NULL ) {
/* For each handler in the list, mark it active by setting its ID bit,
* call the function, and unmark it if the function returns true.
*/
irq_actids[irq] |= hook->id;
/* Call the hooked function. */
if( (*hook->handler)(hook) )
irq_actids[hook->irq] &= ~hook->id;
/* Next hooked function. */
hook = hook->next;
}
/* reenable the IRQ only if there is no active handler */
if (irq_actids[irq] == 0)
hw_intr_unmask(irq);
}
/*
* The function first disables interrupt is need be and restores the state at
* the end. Before returning, it unmasks the IRQ if and only if all active ID
* bits are cleared, and restart a process.
*/
PUBLIC void irq_handle(int irq)
{
irq_hook_t * hook;
/* here we need not to get this IRQ until all the handlers had a say */
assert(irq >= 0 && irq < NR_IRQ_VECTORS);
hw_intr_mask(irq);
hook = irq_handlers[irq];
/* Check for spurious interrupts. */
if(hook == NULL) {
static int nspurious[NR_IRQ_VECTORS], report_interval = 100;
nspurious[irq]++;
if(nspurious[irq] == 1 || !(nspurious[irq] % report_interval)) {
printf("irq_handle: spurious irq %d (count: %d); keeping masked\n",
irq, nspurious[irq]);
if(report_interval < INT_MAX/2)
report_interval *= 2;
}
return;
}
/* Call list of handlers for an IRQ. */
while( hook != NULL ) {
/* For each handler in the list, mark it active by setting its ID bit,
* call the function, and unmark it if the function returns true.
*/
irq_actids[irq] |= hook->id;
/* Call the hooked function. */
if( (*hook->handler)(hook) )
irq_actids[hook->irq] &= ~hook->id;
/* Next hooked function. */
hook = hook->next;
}
/* reenable the IRQ only if there is no active handler */
if (irq_actids[irq] == 0)
hw_intr_unmask(irq);
hw_intr_ack(irq);
}
/* Register an interrupt handler. */
PUBLIC void put_irq_handler( irq_hook_t* hook, int irq,
const irq_handler_t handler)
{
int id;
irq_hook_t **line;
unsigned long bitmap;
if( irq < 0 || irq >= NR_IRQ_VECTORS )
panic("invalid call to put_irq_handler: %d", irq);
line = &irq_handlers[irq];
bitmap = 0;
while ( *line != NULL ) {
if(hook == *line) return; /* extra initialization */
bitmap |= (*line)->id; /* mark ids in use */
line = &(*line)->next;
}
/* find the lowest id not in use */
for (id = 1; id != 0; id <<= 1)
if (!(bitmap & id)) break;
if(id == 0)
panic("Too many handlers for irq: %d", irq);
hook->next = NULL;
hook->handler = handler;
hook->irq = irq;
hook->id = id;
*line = hook;
/* And as last enable the irq at the hardware.
*
* Internal this activates the line or source of the given interrupt.
*/
if((irq_actids[hook->irq] &= ~hook->id) == 0) {
hw_intr_used(irq);
hw_intr_unmask(hook->irq);
}
}
/* Enable/Disable a interrupt line. */
PUBLIC void enable_irq(const irq_hook_t *hook)
{
if((irq_actids[hook->irq] &= ~hook->id) == 0) {
hw_intr_unmask(hook->irq);
}
}
