128 строки
2.5 KiB
C
128 строки
2.5 KiB
C
/*
|
|
* linux/arch/alpha/kernel/irq_pyxis.c
|
|
*
|
|
* Based on code written by David A Rusling (david.rusling@reo.mts.dec.com).
|
|
*
|
|
* IRQ Code common to all PYXIS core logic chips.
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/irq.h>
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/core_cia.h>
|
|
|
|
#include "proto.h"
|
|
#include "irq_impl.h"
|
|
|
|
|
|
/* Note mask bit is true for ENABLED irqs. */
|
|
static unsigned long cached_irq_mask;
|
|
|
|
static inline void
|
|
pyxis_update_irq_hw(unsigned long mask)
|
|
{
|
|
*(vulp)PYXIS_INT_MASK = mask;
|
|
mb();
|
|
*(vulp)PYXIS_INT_MASK;
|
|
}
|
|
|
|
static inline void
|
|
pyxis_enable_irq(unsigned int irq)
|
|
{
|
|
pyxis_update_irq_hw(cached_irq_mask |= 1UL << (irq - 16));
|
|
}
|
|
|
|
static void
|
|
pyxis_disable_irq(unsigned int irq)
|
|
{
|
|
pyxis_update_irq_hw(cached_irq_mask &= ~(1UL << (irq - 16)));
|
|
}
|
|
|
|
static unsigned int
|
|
pyxis_startup_irq(unsigned int irq)
|
|
{
|
|
pyxis_enable_irq(irq);
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
pyxis_end_irq(unsigned int irq)
|
|
{
|
|
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
|
|
pyxis_enable_irq(irq);
|
|
}
|
|
|
|
static void
|
|
pyxis_mask_and_ack_irq(unsigned int irq)
|
|
{
|
|
unsigned long bit = 1UL << (irq - 16);
|
|
unsigned long mask = cached_irq_mask &= ~bit;
|
|
|
|
/* Disable the interrupt. */
|
|
*(vulp)PYXIS_INT_MASK = mask;
|
|
wmb();
|
|
/* Ack PYXIS PCI interrupt. */
|
|
*(vulp)PYXIS_INT_REQ = bit;
|
|
mb();
|
|
/* Re-read to force both writes. */
|
|
*(vulp)PYXIS_INT_MASK;
|
|
}
|
|
|
|
static struct hw_interrupt_type pyxis_irq_type = {
|
|
.typename = "PYXIS",
|
|
.startup = pyxis_startup_irq,
|
|
.shutdown = pyxis_disable_irq,
|
|
.enable = pyxis_enable_irq,
|
|
.disable = pyxis_disable_irq,
|
|
.ack = pyxis_mask_and_ack_irq,
|
|
.end = pyxis_end_irq,
|
|
};
|
|
|
|
void
|
|
pyxis_device_interrupt(unsigned long vector)
|
|
{
|
|
unsigned long pld;
|
|
unsigned int i;
|
|
|
|
/* Read the interrupt summary register of PYXIS */
|
|
pld = *(vulp)PYXIS_INT_REQ;
|
|
pld &= cached_irq_mask;
|
|
|
|
/*
|
|
* Now for every possible bit set, work through them and call
|
|
* the appropriate interrupt handler.
|
|
*/
|
|
while (pld) {
|
|
i = ffz(~pld);
|
|
pld &= pld - 1; /* clear least bit set */
|
|
if (i == 7)
|
|
isa_device_interrupt(vector);
|
|
else
|
|
handle_irq(16+i);
|
|
}
|
|
}
|
|
|
|
void __init
|
|
init_pyxis_irqs(unsigned long ignore_mask)
|
|
{
|
|
long i;
|
|
|
|
*(vulp)PYXIS_INT_MASK = 0; /* disable all */
|
|
*(vulp)PYXIS_INT_REQ = -1; /* flush all */
|
|
mb();
|
|
|
|
/* Send -INTA pulses to clear any pending interrupts ...*/
|
|
*(vuip) CIA_IACK_SC;
|
|
|
|
for (i = 16; i < 48; ++i) {
|
|
if ((ignore_mask >> i) & 1)
|
|
continue;
|
|
irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
|
|
irq_desc[i].chip = &pyxis_irq_type;
|
|
}
|
|
|
|
setup_irq(16+7, &isa_cascade_irqaction);
|
|
}
|