272 lines
6.5 KiB
C
272 lines
6.5 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
/*
|
||
|
|
* Macintosh interrupts
|
||
|
|
*
|
||
|
|
* General design:
|
||
|
|
* In contrary to the Amiga and Atari platforms, the Mac hardware seems to
|
||
|
|
* exclusively use the autovector interrupts (the 'generic level0-level7'
|
||
|
|
* interrupts with exception vectors 0x19-0x1f). The following interrupt levels
|
||
|
|
* are used:
|
||
|
|
* 1 - VIA1
|
||
|
|
* - slot 0: one second interrupt (CA2)
|
||
|
|
* - slot 1: VBlank (CA1)
|
||
|
|
* - slot 2: ADB data ready (SR full)
|
||
|
|
* - slot 3: ADB data (CB2)
|
||
|
|
* - slot 4: ADB clock (CB1)
|
||
|
|
* - slot 5: timer 2
|
||
|
|
* - slot 6: timer 1
|
||
|
|
* - slot 7: status of IRQ; signals 'any enabled int.'
|
||
|
|
*
|
||
|
|
* 2 - VIA2 or RBV
|
||
|
|
* - slot 0: SCSI DRQ (CA2)
|
||
|
|
* - slot 1: NUBUS IRQ (CA1) need to read port A to find which
|
||
|
|
* - slot 2: /EXP IRQ (only on IIci)
|
||
|
|
* - slot 3: SCSI IRQ (CB2)
|
||
|
|
* - slot 4: ASC IRQ (CB1)
|
||
|
|
* - slot 5: timer 2 (not on IIci)
|
||
|
|
* - slot 6: timer 1 (not on IIci)
|
||
|
|
* - slot 7: status of IRQ; signals 'any enabled int.'
|
||
|
|
*
|
||
|
|
* Levels 3-6 vary by machine type. For VIA or RBV Macintoshes:
|
||
|
|
*
|
||
|
|
* 3 - unused (?)
|
||
|
|
*
|
||
|
|
* 4 - SCC
|
||
|
|
*
|
||
|
|
* 5 - unused (?)
|
||
|
|
* [serial errors or special conditions seem to raise level 6
|
||
|
|
* interrupts on some models (LC4xx?)]
|
||
|
|
*
|
||
|
|
* 6 - off switch (?)
|
||
|
|
*
|
||
|
|
* Machines with Quadra-like VIA hardware, except PSC and PMU machines, support
|
||
|
|
* an alternate interrupt mapping, as used by A/UX. It spreads ethernet and
|
||
|
|
* sound out to their own autovector IRQs and gives VIA1 a higher priority:
|
||
|
|
*
|
||
|
|
* 1 - unused (?)
|
||
|
|
*
|
||
|
|
* 3 - on-board SONIC
|
||
|
|
*
|
||
|
|
* 5 - Apple Sound Chip (ASC)
|
||
|
|
*
|
||
|
|
* 6 - VIA1
|
||
|
|
*
|
||
|
|
* For OSS Macintoshes (IIfx only), we apply an interrupt mapping similar to
|
||
|
|
* the Quadra (A/UX) mapping:
|
||
|
|
*
|
||
|
|
* 1 - ISM IOP (ADB)
|
||
|
|
*
|
||
|
|
* 2 - SCSI
|
||
|
|
*
|
||
|
|
* 3 - NuBus
|
||
|
|
*
|
||
|
|
* 4 - SCC IOP
|
||
|
|
*
|
||
|
|
* 6 - VIA1
|
||
|
|
*
|
||
|
|
* For PSC Macintoshes (660AV, 840AV):
|
||
|
|
*
|
||
|
|
* 3 - PSC level 3
|
||
|
|
* - slot 0: MACE
|
||
|
|
*
|
||
|
|
* 4 - PSC level 4
|
||
|
|
* - slot 1: SCC channel A interrupt
|
||
|
|
* - slot 2: SCC channel B interrupt
|
||
|
|
* - slot 3: MACE DMA
|
||
|
|
*
|
||
|
|
* 5 - PSC level 5
|
||
|
|
*
|
||
|
|
* 6 - PSC level 6
|
||
|
|
*
|
||
|
|
* Finally we have good 'ole level 7, the non-maskable interrupt:
|
||
|
|
*
|
||
|
|
* 7 - NMI (programmer's switch on the back of some Macs)
|
||
|
|
* Also RAM parity error on models which support it (IIc, IIfx?)
|
||
|
|
*
|
||
|
|
* The current interrupt logic looks something like this:
|
||
|
|
*
|
||
|
|
* - We install dispatchers for the autovector interrupts (1-7). These
|
||
|
|
* dispatchers are responsible for querying the hardware (the
|
||
|
|
* VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using
|
||
|
|
* this information a machspec interrupt number is generated by placing the
|
||
|
|
* index of the interrupt hardware into the low three bits and the original
|
||
|
|
* autovector interrupt number in the upper 5 bits. The handlers for the
|
||
|
|
* resulting machspec interrupt are then called.
|
||
|
|
*
|
||
|
|
* - Nubus is a special case because its interrupts are hidden behind two
|
||
|
|
* layers of hardware. Nubus interrupts come in as index 1 on VIA #2,
|
||
|
|
* which translates to IRQ number 17. In this spot we install _another_
|
||
|
|
* dispatcher. This dispatcher finds the interrupting slot number (9-F) and
|
||
|
|
* then forms a new machspec interrupt number as above with the slot number
|
||
|
|
* minus 9 in the low three bits and the pseudo-level 7 in the upper five
|
||
|
|
* bits. The handlers for this new machspec interrupt number are then
|
||
|
|
* called. This puts Nubus interrupts into the range 56-62.
|
||
|
|
*
|
||
|
|
* - The Baboon interrupts (used on some PowerBooks) are an even more special
|
||
|
|
* case. They're hidden behind the Nubus slot $C interrupt thus adding a
|
||
|
|
* third layer of indirection. Why oh why did the Apple engineers do that?
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/types.h>
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <linux/sched.h>
|
||
|
|
#include <linux/sched/debug.h>
|
||
|
|
#include <linux/interrupt.h>
|
||
|
|
#include <linux/irq.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
|
||
|
|
#include <asm/irq.h>
|
||
|
|
#include <asm/macintosh.h>
|
||
|
|
#include <asm/macints.h>
|
||
|
|
#include <asm/mac_via.h>
|
||
|
|
#include <asm/mac_psc.h>
|
||
|
|
#include <asm/mac_oss.h>
|
||
|
|
#include <asm/mac_iop.h>
|
||
|
|
#include <asm/mac_baboon.h>
|
||
|
|
#include <asm/hwtest.h>
|
||
|
|
#include <asm/irq_regs.h>
|
||
|
|
|
||
|
|
extern void show_registers(struct pt_regs *);
|
||
|
|
|
||
|
|
irqreturn_t mac_nmi_handler(int, void *);
|
||
|
|
|
||
|
|
static unsigned int mac_irq_startup(struct irq_data *);
|
||
|
|
static void mac_irq_shutdown(struct irq_data *);
|
||
|
|
|
||
|
|
static struct irq_chip mac_irq_chip = {
|
||
|
|
.name = "mac",
|
||
|
|
.irq_enable = mac_irq_enable,
|
||
|
|
.irq_disable = mac_irq_disable,
|
||
|
|
.irq_startup = mac_irq_startup,
|
||
|
|
.irq_shutdown = mac_irq_shutdown,
|
||
|
|
};
|
||
|
|
|
||
|
|
void __init mac_init_IRQ(void)
|
||
|
|
{
|
||
|
|
m68k_setup_irq_controller(&mac_irq_chip, handle_simple_irq, IRQ_USER,
|
||
|
|
NUM_MAC_SOURCES - IRQ_USER);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Now register the handlers for the master IRQ handlers
|
||
|
|
* at levels 1-7. Most of the work is done elsewhere.
|
||
|
|
*/
|
||
|
|
|
||
|
|
if (oss_present)
|
||
|
|
oss_register_interrupts();
|
||
|
|
else
|
||
|
|
via_register_interrupts();
|
||
|
|
if (psc)
|
||
|
|
psc_register_interrupts();
|
||
|
|
if (baboon_present)
|
||
|
|
baboon_register_interrupts();
|
||
|
|
iop_register_interrupts();
|
||
|
|
if (request_irq(IRQ_AUTO_7, mac_nmi_handler, 0, "NMI",
|
||
|
|
mac_nmi_handler))
|
||
|
|
pr_err("Couldn't register NMI\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* mac_irq_enable - enable an interrupt source
|
||
|
|
* mac_irq_disable - disable an interrupt source
|
||
|
|
*
|
||
|
|
* These routines are just dispatchers to the VIA/OSS/PSC routines.
|
||
|
|
*/
|
||
|
|
|
||
|
|
void mac_irq_enable(struct irq_data *data)
|
||
|
|
{
|
||
|
|
int irq = data->irq;
|
||
|
|
int irq_src = IRQ_SRC(irq);
|
||
|
|
|
||
|
|
switch(irq_src) {
|
||
|
|
case 1:
|
||
|
|
case 2:
|
||
|
|
case 7:
|
||
|
|
if (oss_present)
|
||
|
|
oss_irq_enable(irq);
|
||
|
|
else
|
||
|
|
via_irq_enable(irq);
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
case 4:
|
||
|
|
case 5:
|
||
|
|
case 6:
|
||
|
|
if (psc)
|
||
|
|
psc_irq_enable(irq);
|
||
|
|
else if (oss_present)
|
||
|
|
oss_irq_enable(irq);
|
||
|
|
break;
|
||
|
|
case 8:
|
||
|
|
if (baboon_present)
|
||
|
|
baboon_irq_enable(irq);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void mac_irq_disable(struct irq_data *data)
|
||
|
|
{
|
||
|
|
int irq = data->irq;
|
||
|
|
int irq_src = IRQ_SRC(irq);
|
||
|
|
|
||
|
|
switch(irq_src) {
|
||
|
|
case 1:
|
||
|
|
case 2:
|
||
|
|
case 7:
|
||
|
|
if (oss_present)
|
||
|
|
oss_irq_disable(irq);
|
||
|
|
else
|
||
|
|
via_irq_disable(irq);
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
case 4:
|
||
|
|
case 5:
|
||
|
|
case 6:
|
||
|
|
if (psc)
|
||
|
|
psc_irq_disable(irq);
|
||
|
|
else if (oss_present)
|
||
|
|
oss_irq_disable(irq);
|
||
|
|
break;
|
||
|
|
case 8:
|
||
|
|
if (baboon_present)
|
||
|
|
baboon_irq_disable(irq);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static unsigned int mac_irq_startup(struct irq_data *data)
|
||
|
|
{
|
||
|
|
int irq = data->irq;
|
||
|
|
|
||
|
|
if (IRQ_SRC(irq) == 7 && !oss_present)
|
||
|
|
via_nubus_irq_startup(irq);
|
||
|
|
else
|
||
|
|
mac_irq_enable(data);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void mac_irq_shutdown(struct irq_data *data)
|
||
|
|
{
|
||
|
|
int irq = data->irq;
|
||
|
|
|
||
|
|
if (IRQ_SRC(irq) == 7 && !oss_present)
|
||
|
|
via_nubus_irq_shutdown(irq);
|
||
|
|
else
|
||
|
|
mac_irq_disable(data);
|
||
|
|
}
|
||
|
|
|
||
|
|
static volatile int in_nmi;
|
||
|
|
|
||
|
|
irqreturn_t mac_nmi_handler(int irq, void *dev_id)
|
||
|
|
{
|
||
|
|
if (in_nmi)
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
in_nmi = 1;
|
||
|
|
|
||
|
|
pr_info("Non-Maskable Interrupt\n");
|
||
|
|
show_registers(get_irq_regs());
|
||
|
|
|
||
|
|
in_nmi = 0;
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
}
|