original_kernel/arch/mips/jazz/irq.c

100 lines
2.5 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1992 Linus Torvalds
* Copyright (C) 1994 - 2001, 2003 Ralf Baechle
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <asm/i8259.h>
#include <asm/io.h>
#include <asm/jazz.h>
extern asmlinkage void jazz_handle_int(void);
static DEFINE_SPINLOCK(r4030_lock);
static void enable_r4030_irq(unsigned int irq)
{
unsigned int mask = 1 << (irq - JAZZ_PARALLEL_IRQ);
unsigned long flags;
spin_lock_irqsave(&r4030_lock, flags);
mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
spin_unlock_irqrestore(&r4030_lock, flags);
}
static unsigned int startup_r4030_irq(unsigned int irq)
{
enable_r4030_irq(irq);
return 0; /* never anything pending */
}
#define shutdown_r4030_irq disable_r4030_irq
void disable_r4030_irq(unsigned int irq)
{
unsigned int mask = ~(1 << (irq - JAZZ_PARALLEL_IRQ));
unsigned long flags;
spin_lock_irqsave(&r4030_lock, flags);
mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
spin_unlock_irqrestore(&r4030_lock, flags);
}
#define mask_and_ack_r4030_irq disable_r4030_irq
static void end_r4030_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
enable_r4030_irq(irq);
}
static struct hw_interrupt_type r4030_irq_type = {
.typename = "R4030",
.startup = startup_r4030_irq,
.shutdown = shutdown_r4030_irq,
.enable = enable_r4030_irq,
.disable = disable_r4030_irq,
.ack = mask_and_ack_r4030_irq,
.end = end_r4030_irq,
};
void __init init_r4030_ints(void)
{
int i;
for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++) {
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = 0;
irq_desc[i].depth = 1;
irq_desc[i].handler = &r4030_irq_type;
}
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
r4030_read_reg16(JAZZ_IO_IRQ_SOURCE); /* clear pending IRQs */
r4030_read_reg32(JAZZ_R4030_INVAL_ADDR); /* clear error bits */
}
/*
* On systems with i8259-style interrupt controllers we assume for
* driver compatibility reasons interrupts 0 - 15 to be the i8259
* interrupts even if the hardware uses a different interrupt numbering.
*/
void __init arch_init_irq(void)
{
set_except_vector(0, jazz_handle_int);
init_i8259_irqs(); /* Integrated i8259 */
init_r4030_ints();
change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
}