linux-stable/arch/m68k/mac/psc.c
Finn Thain 16a1a66a5e m68k/mac: Clean up interrupt debug macros and printk statements
Mac interrupt code has been debugged. The Penguin deficiencies that
still cause unhandled interrupts aren't fixable here. Besides,
interrupts are fast and frequent and these printk statements
were never really useful IMO. Remove them.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-02-09 14:18:19 +01:00

167 lines
3.8 KiB
C

/*
* Apple Peripheral System Controller (PSC)
*
* The PSC is used on the AV Macs to control IO functions not handled
* by the VIAs (Ethernet, DSP, SCC).
*
* TO DO:
*
* Try to figure out what's going on in pIFR5 and pIFR6. There seem to be
* persisant interrupt conditions in those registers and I have no idea what
* they are. Granted it doesn't affect since we're not enabling any interrupts
* on those levels at the moment, but it would be nice to know. I have a feeling
* they aren't actually interrupt lines but data lines (to the DSP?)
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <asm/traps.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_psc.h>
#define DEBUG_PSC
volatile __u8 *psc;
EXPORT_SYMBOL_GPL(psc);
/*
* Debugging dump, used in various places to see what's going on.
*/
static void psc_debug_dump(void)
{
int i;
if (!psc)
return;
for (i = 0x30 ; i < 0x70 ; i += 0x10) {
printk("PSC #%d: IFR = 0x%02X IER = 0x%02X\n",
i >> 4,
(int) psc_read_byte(pIFRbase + i),
(int) psc_read_byte(pIERbase + i));
}
}
/*
* Try to kill all DMA channels on the PSC. Not sure how this his
* supposed to work; this is code lifted from macmace.c and then
* expanded to cover what I think are the other 7 channels.
*/
static __init void psc_dma_die_die_die(void)
{
int i;
printk("Killing all PSC DMA channels...");
for (i = 0 ; i < 9 ; i++) {
psc_write_word(PSC_CTL_BASE + (i << 4), 0x8800);
psc_write_word(PSC_CTL_BASE + (i << 4), 0x1000);
psc_write_word(PSC_CMD_BASE + (i << 5), 0x1100);
psc_write_word(PSC_CMD_BASE + (i << 5) + 0x10, 0x1100);
}
printk("done!\n");
}
/*
* Initialize the PSC. For now this just involves shutting down all
* interrupt sources using the IERs.
*/
void __init psc_init(void)
{
int i;
if (macintosh_config->ident != MAC_MODEL_C660
&& macintosh_config->ident != MAC_MODEL_Q840)
{
psc = NULL;
return;
}
/*
* The PSC is always at the same spot, but using psc
* keeps things consistent with the psc_xxxx functions.
*/
psc = (void *) PSC_BASE;
printk("PSC detected at %p\n", psc);
psc_dma_die_die_die();
#ifdef DEBUG_PSC
psc_debug_dump();
#endif
/*
* Mask and clear all possible interrupts
*/
for (i = 0x30 ; i < 0x70 ; i += 0x10) {
psc_write_byte(pIERbase + i, 0x0F);
psc_write_byte(pIFRbase + i, 0x0F);
}
}
/*
* PSC interrupt handler. It's a lot like the VIA interrupt handler.
*/
static void psc_irq(struct irq_desc *desc)
{
unsigned int offset = (unsigned int)irq_desc_get_handler_data(desc);
unsigned int irq = irq_desc_get_irq(desc);
int pIFR = pIFRbase + offset;
int pIER = pIERbase + offset;
int irq_num;
unsigned char irq_bit, events;
events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF;
if (!events)
return;
irq_num = irq << 3;
irq_bit = 1;
do {
if (events & irq_bit) {
psc_write_byte(pIFR, irq_bit);
generic_handle_irq(irq_num);
}
irq_num++;
irq_bit <<= 1;
} while (events >= irq_bit);
}
/*
* Register the PSC interrupt dispatchers for autovector interrupts 3-6.
*/
void __init psc_register_interrupts(void)
{
irq_set_chained_handler_and_data(IRQ_AUTO_3, psc_irq, (void *)0x30);
irq_set_chained_handler_and_data(IRQ_AUTO_4, psc_irq, (void *)0x40);
irq_set_chained_handler_and_data(IRQ_AUTO_5, psc_irq, (void *)0x50);
irq_set_chained_handler_and_data(IRQ_AUTO_6, psc_irq, (void *)0x60);
}
void psc_irq_enable(int irq) {
int irq_src = IRQ_SRC(irq);
int irq_idx = IRQ_IDX(irq);
int pIER = pIERbase + (irq_src << 4);
psc_write_byte(pIER, (1 << irq_idx) | 0x80);
}
void psc_irq_disable(int irq) {
int irq_src = IRQ_SRC(irq);
int irq_idx = IRQ_IDX(irq);
int pIER = pIERbase + (irq_src << 4);
psc_write_byte(pIER, 1 << irq_idx);
}