167 lines
3.8 KiB
C
167 lines
3.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* 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(KERN_DEBUG "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;
|
|
|
|
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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
pr_debug("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);
|
|
}
|