Viewing file:  cia.c (4.21 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* linux/arch/m68k/amiga/cia.c - CIA support
*
* Copyright (C) 1996 Roman Zippel
*
* The concept of some functions bases on the original Amiga OS function
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/init.h>
#include <asm/irq.h>
#include <asm/amigahw.h>
#include <asm/amigaints.h>
struct ciabase {
volatile struct CIA *cia;
unsigned char icr_mask, icr_data;
unsigned short int_mask;
int handler_irq, cia_irq, server_irq;
char *name;
irq_handler_t irq_list[CIA_IRQS];
} ciaa_base = {
&ciaa, 0, 0, IF_PORTS,
IRQ_AMIGA_AUTO_2, IRQ_AMIGA_CIAA,
IRQ_AMIGA_PORTS,
"CIAA handler"
}, ciab_base = {
&ciab, 0, 0, IF_EXTER,
IRQ_AMIGA_AUTO_6, IRQ_AMIGA_CIAB,
IRQ_AMIGA_EXTER,
"CIAB handler"
};
/*
* Cause or clear CIA interrupts, return old interrupt status.
*/
unsigned char cia_set_irq(struct ciabase *base, unsigned char mask)
{
unsigned char old;
old = (base->icr_data |= base->cia->icr);
if (mask & CIA_ICR_SETCLR)
base->icr_data |= mask;
else
base->icr_data &= ~mask;
if (base->icr_data & base->icr_mask)
custom.intreq = IF_SETCLR | base->int_mask;
return old & base->icr_mask;
}
/*
* Enable or disable CIA interrupts, return old interrupt mask,
* interrupts will only be enabled if a handler exists
*/
unsigned char cia_able_irq(struct ciabase *base, unsigned char mask)
{
unsigned char old, tmp;
int i;
old = base->icr_mask;
base->icr_data |= base->cia->icr;
base->cia->icr = mask;
if (mask & CIA_ICR_SETCLR)
base->icr_mask |= mask;
else
base->icr_mask &= ~mask;
base->icr_mask &= CIA_ICR_ALL;
for (i = 0, tmp = 1; i < CIA_IRQS; i++, tmp <<= 1) {
if ((tmp & base->icr_mask) && !base->irq_list[i].handler) {
base->icr_mask &= ~tmp;
base->cia->icr = tmp;
}
}
if (base->icr_data & base->icr_mask)
custom.intreq = IF_SETCLR | base->int_mask;
return old;
}
int cia_request_irq(struct ciabase *base, unsigned int irq,
void (*handler)(int, void *, struct pt_regs *),
unsigned long flags, const char *devname, void *dev_id)
{
unsigned char mask;
base->irq_list[irq].handler = handler;
base->irq_list[irq].flags = flags;
base->irq_list[irq].dev_id = dev_id;
base->irq_list[irq].devname = devname;
/* enable the interrupt */
mask = 1 << irq;
cia_set_irq(base, mask);
cia_able_irq(base, CIA_ICR_SETCLR | mask);
return 0;
}
void cia_free_irq(struct ciabase *base, unsigned int irq, void *dev_id)
{
if (base->irq_list[irq].dev_id != dev_id)
printk("%s: removing probably wrong IRQ %i from %s\n",
__FUNCTION__, base->cia_irq + irq,
base->irq_list[irq].devname);
base->irq_list[irq].handler = NULL;
base->irq_list[irq].flags = 0;
cia_able_irq(base, 1 << irq);
}
static void cia_handler(int irq, void *dev_id, struct pt_regs *fp)
{
struct ciabase *base = (struct ciabase *)dev_id;
int mach_irq, i;
unsigned char ints;
mach_irq = base->cia_irq;
irq = SYS_IRQS + mach_irq;
ints = cia_set_irq(base, CIA_ICR_ALL);
custom.intreq = base->int_mask;
for (i = 0; i < CIA_IRQS; i++, irq++, mach_irq++) {
if (ints & 1) {
kstat.irqs[0][irq]++;
base->irq_list[i].handler(mach_irq, base->irq_list[i].dev_id, fp);
}
ints >>= 1;
}
amiga_do_irq_list(base->server_irq, fp);
}
void __init cia_init_IRQ(struct ciabase *base)
{
int i;
/* init isr handlers */
for (i = 0; i < CIA_IRQS; i++) {
base->irq_list[i].handler = NULL;
base->irq_list[i].flags = 0;
}
/* clear any pending interrupt and turn off all interrupts */
cia_set_irq(base, CIA_ICR_ALL);
cia_able_irq(base, CIA_ICR_ALL);
/* install CIA handler */
request_irq(base->handler_irq, cia_handler, 0, base->name, base);
custom.intena = IF_SETCLR | base->int_mask;
}
int cia_get_irq_list(struct ciabase *base, char *buf)
{
int i, j, len = 0;
j = base->cia_irq;
for (i = 0; i < CIA_IRQS; i++) {
len += sprintf(buf+len, "cia %2d: %10d ", j + i,
kstat.irqs[0][SYS_IRQS + j + i]);
len += sprintf(buf+len, " ");
len += sprintf(buf+len, "%s\n", base->irq_list[i].devname);
}
return len;
}
|