linux/arch/mips/dec/kn02-irq.c
Atsushi Nemoto 1603b5aca4 [MIPS] IRQ cleanups
This is a big irq cleanup patch.

* Use set_irq_chip() to register irq_chip.
* Initialize .mask, .unmask, .mask_ack field.  Functions for these
  method are already exist in most case.
* Do not initialize .startup, .shutdown, .enable, .disable fields if
  default routines provided by irq_chip_set_defaults() were suitable.
* Remove redundant irq_desc initializations.
* Remove unnecessary local_irq_save/local_irq_restore, spin_lock.

With this cleanup, it would be easy to switch to slightly lightwait
irq flow handlers (handle_level_irq(), etc.) instead of __do_IRQ().

Though whole this patch is quite large, changes in each irq_chip are
not quite simple.  Please review and test on your platform.  Thanks.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:46 +00:00

92 lines
2.0 KiB
C

/*
* linux/arch/mips/dec/kn02-irq.c
*
* DECstation 5000/200 (KN02) Control and Status Register
* interrupts.
*
* Copyright (c) 2002, 2003, 2005 Maciej W. Rozycki
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/types.h>
#include <asm/dec/kn02.h>
/*
* Bits 7:0 of the Control Register are write-only -- the
* corresponding bits of the Status Register have a different
* meaning. Hence we use a cache. It speeds up things a bit
* as well.
*
* There is no default value -- it has to be initialized.
*/
u32 cached_kn02_csr;
static int kn02_irq_base;
static inline void unmask_kn02_irq(unsigned int irq)
{
volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
KN02_CSR);
cached_kn02_csr |= (1 << (irq - kn02_irq_base + 16));
*csr = cached_kn02_csr;
}
static inline void mask_kn02_irq(unsigned int irq)
{
volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
KN02_CSR);
cached_kn02_csr &= ~(1 << (irq - kn02_irq_base + 16));
*csr = cached_kn02_csr;
}
static void ack_kn02_irq(unsigned int irq)
{
mask_kn02_irq(irq);
iob();
}
static void end_kn02_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
unmask_kn02_irq(irq);
}
static struct irq_chip kn02_irq_type = {
.typename = "KN02-CSR",
.ack = ack_kn02_irq,
.mask = mask_kn02_irq,
.mask_ack = ack_kn02_irq,
.unmask = unmask_kn02_irq,
.end = end_kn02_irq,
};
void __init init_kn02_irqs(int base)
{
volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
KN02_CSR);
int i;
/* Mask interrupts. */
cached_kn02_csr &= ~KN02_CSR_IOINTEN;
*csr = cached_kn02_csr;
iob();
for (i = base; i < base + KN02_IRQ_LINES; i++)
set_irq_chip(i, &kn02_irq_type);
kn02_irq_base = base;
}