/*
*
* Copyright (C) 2005 Embedded Alley Solutions, Inc
* Ported to 2.6.
*
* Per Hallsmark, per.hallsmark@mvista.com
* Copyright (C) 2000, 2001 MIPS Technologies, Inc.
* Copyright (C) 2001 Ralf Baechle
*
* Cleaned up and bug fixing: Pete Popov, ppopov@embeddedalley.com
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
*/
#include <linux/compiler.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/random.h>
#include <linux/module.h>
#include <asm/io.h>
#include <int.h>
#include <uart.h>
/* default prio for interrupts */
/* first one is a no-no so therefore always prio 0 (disabled) */
static char gic_prio[PNX8550_INT_GIC_TOTINT] = {
0, 1, 1, 1, 1, 15, 1, 1, 1, 1, // 0 - 9
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 10 - 19
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 20 - 29
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 30 - 39
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 40 - 49
1, 1, 1, 1, 1, 1, 1, 1, 2, 1, // 50 - 59
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 60 - 69
1 // 70
};
static void hw0_irqdispatch(int irq)
{
/* find out which interrupt */
irq = PNX8550_GIC_VECTOR_0 >> 3;
if (irq == 0) {
printk("hw0_irqdispatch: irq 0, spurious interrupt?\n");
return;
}
do_IRQ(PNX8550_INT_GIC_MIN + irq);
}
static void timer_irqdispatch(int irq)
{
irq = (0x01c0 & read_c0_config7()) >> 6;
if (unlikely(irq == 0)) {
printk("timer_irqdispatch: irq 0, spurious interrupt?\n");
return;
}
if (irq & 0x1)
do_IRQ(PNX8550_INT_TIMER1);
if (irq & 0x2)
do_IRQ(PNX8550_INT_TIMER2);
if (irq & 0x4)
do_IRQ(PNX8550_INT_TIMER3);
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
if (pending & STATUSF_IP2)
hw0_irqdispatch(2);
else if (pending & STATUSF_IP7) {
if (read_c0_config7() & 0x01c0)
timer_irqdispatch(7);
} else
spurious_interrupt();
}
static inline void modify_cp0_intmask(unsigned clr_mask, unsigned set_mask)
{
unsigned long status = read_c0_status();
status &= ~((clr_mask & 0xFF) << 8);
status |= (set_mask & 0xFF) << 8;
write_c0_status(status);
}
static inline void mask_gic_int(unsigned int irq_nr)
{
/* interrupt disabled, bit 26(WE_ENABLE)=1 and bit 16(enable)=0 */
PNX8550_GIC_REQ(irq_nr) = 1<<28; /* set priority to 0 */
}
static inline void unmask_gic_int(unsigned int irq_nr)
{
/* set prio mask to lower four bits and enable interrupt */
PNX8550_GIC_REQ(irq_nr) = (1<<26 | 1<<16) | (1<<28) | gic_prio[irq_nr];
}
static inline void mask_irq(unsigned int irq_nr)
{
if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) {
modify_cp0_intmask(1 << irq_nr, 0);
} else if ((PNX8550_INT_GIC_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_GIC_MAX)) {
mask_gic_int(irq_nr - PNX8550_INT_GIC_MIN);
} else if ((PNX8550_INT_TIMER_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_TIMER_MAX)) {
modify_cp0_intmask(1 << 7, 0);
} else {
printk("mask_irq: irq %d doesn't exist!\n", irq_nr);
}
}
static inline void unmask_irq(unsigned int irq_nr)
{
if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) {
modify_cp0_intmask(0, 1 << irq_nr);
} else if ((PNX8550_INT_GIC_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_GIC_MAX)) {
unmask_gic_int(irq_nr - PNX8550_INT_GIC_MIN);
} else if ((PNX8550_INT_TIMER_MIN <= irq_nr) &&
(irq_nr <= PNX8550_INT_TIMER_MAX)) {
modify_cp0_intmask(0, 1 << 7);
} else {
printk("mask_irq: irq %d doesn't exist!\n", irq_nr);
}
}
int pnx8550_set_gic_priority(int irq, int priority)
{
int gic_irq = irq-PNX8550_INT_GIC_MIN;
int prev_priority = PNX8550_GIC_REQ(gic_irq) & 0xf;
gic_prio[gic_irq] = priority;
PNX8550_GIC_REQ(gic_irq) |= (0x10000000 | gic_prio[gic_irq]);
return prev_priority;
}
static struct irq_chip level_irq_type = {
.name = "PNX Level IRQ",
.ack = mask_irq,
.mask = mask_irq,
.mask_ack = mask_irq,
.unmask = unmask_irq,
};
static struct irqaction gic_action = {
.handler = no_action,
.flags = IRQF_DISABLED,
.name = "GIC",
};
static struct irqaction timer_action = {
.handler = no_action,
.flags = IRQF_DISABLED | IRQF_TIMER,
.name = "Timer",
};
void __init arch_init_irq(void)
{
int i;
int configPR;
for (i = 0; i < PNX8550_INT_CP0_TOTINT; i++) {
set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq);
mask_irq(i); /* mask the irq just in case */
}
/* init of GIC/IPC interrupts */
/* should be done before cp0 since cp0 init enables the GIC int */
for (i = PNX8550_INT_GIC_MIN; i <= PNX8550_INT_GIC_MAX; i++) {
int gic_int_line = i - PNX8550_INT_GIC_MIN;
if (gic_int_line == 0 )
continue; // don't fiddle with int 0
/*
* enable change of TARGET, ENABLE and ACTIVE_LOW bits
* set TARGET 0 to route through hw0 interrupt
* set ACTIVE_LOW 0 active high (correct?)
*
* We really should setup an interrupt description table
* to do this nicely.
* Note, PCI INTA is active low on the bus, but inverted
* in the GIC, so to us it's active high.
*/
PNX8550_GIC_REQ(i - PNX8550_INT_GIC_MIN) = 0x1E000000;
/* mask/priority is still 0 so we will not get any
* interrupts until it is unmasked */
set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq);
}
/* Priority level 0 */
PNX8550_GIC_PRIMASK_0 = PNX8550_GIC_PRIMASK_1 = 0;
/* Set int vector table address */
PNX8550_GIC_VECTOR_0 = PNX8550_GIC_VECTOR_1 = 0;
set_irq_chip_and_handler(MIPS_CPU_GIC_IRQ, &level_irq_type,
handle_level_irq);
setup_irq(MIPS_CPU_GIC_IRQ, &gic_action);
/* init of Timer interrupts */
for (i = PNX8550_INT_TIMER_MIN; i <= PNX8550_INT_TIMER_MAX; i++)
set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq);
/* Stop Timer 1-3 */
configPR = read_c0_config7();
configPR |= 0x00000038;
write_c0_config7(configPR);
set_irq_chip_and_handler(MIPS_CPU_TIMER_IRQ, &level_irq_type,
handle_level_irq);
setup_irq(MIPS_CPU_TIMER_IRQ, &timer_action);
}
EXPORT_SYMBOL(pnx8550_set_gic_priority);
