linux_old1/arch/m68k/mac/baboon.c

100 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Baboon Custom IC Management
*
* The Baboon custom IC controls the IDE, PCMCIA and media bay on the
* PowerBook 190. It multiplexes multiple interrupt sources onto the
* Nubus slot $C interrupt.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/irq.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_baboon.h>
int baboon_present;
static volatile struct baboon *baboon;
#if 0
extern int macide_ack_intr(struct ata_channel *);
#endif
/*
* Baboon initialization.
*/
void __init baboon_init(void)
{
if (macintosh_config->ident != MAC_MODEL_PB190) {
baboon = NULL;
baboon_present = 0;
return;
}
baboon = (struct baboon *) BABOON_BASE;
baboon_present = 1;
printk("Baboon detected at %p\n", baboon);
}
/*
* Baboon interrupt handler. This works a lot like a VIA.
*/
static void baboon_irq(struct irq_desc *desc)
{
int irq_bit, irq_num;
unsigned char events;
events = baboon->mb_ifr & 0x07;
if (!events)
return;
irq_num = IRQ_BABOON_0;
irq_bit = 1;
do {
if (events & irq_bit) {
baboon->mb_ifr &= ~irq_bit;
generic_handle_irq(irq_num);
}
irq_bit <<= 1;
irq_num++;
} while(events >= irq_bit);
#if 0
if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
/* for now we need to smash all interrupts */
baboon->mb_ifr &= ~events;
#endif
}
/*
* Register the Baboon interrupt dispatcher on nubus slot $C.
*/
void __init baboon_register_interrupts(void)
{
irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
}
/*
* The means for masking individual Baboon interrupts remains a mystery.
* However, since we only use the IDE IRQ, we can just enable/disable all
* Baboon interrupts. If/when we handle more than one Baboon IRQ, we must
* either figure out how to mask them individually or else implement the
* same workaround that's used for NuBus slots (see nubus_disabled and
* via_nubus_irq_shutdown).
*/
void baboon_irq_enable(int irq)
{
mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
}
void baboon_irq_disable(int irq)
{
mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
}