linux/arch/sh/kernel/cpu/irq/imask.c
Ingo Molnar d1bef4ed5f [PATCH] genirq: rename desc->handler to desc->chip
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch.  But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly.  The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00

111 lines
2.5 KiB
C

/*
* arch/sh/kernel/cpu/irq/imask.c
*
* Copyright (C) 1999, 2000 Niibe Yutaka
*
* Simple interrupt handling using IMASK of SR register.
*
*/
/* NOTE: Will not work on level 15 */
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/irq.h>
#include <asm/system.h>
#include <asm/irq.h>
/* Bitmap of IRQ masked */
static unsigned long imask_mask = 0x7fff;
static int interrupt_priority = 0;
static void enable_imask_irq(unsigned int irq);
static void disable_imask_irq(unsigned int irq);
static void shutdown_imask_irq(unsigned int irq);
static void mask_and_ack_imask(unsigned int);
static void end_imask_irq(unsigned int irq);
#define IMASK_PRIORITY 15
static unsigned int startup_imask_irq(unsigned int irq)
{
/* Nothing to do */
return 0; /* never anything pending */
}
static struct hw_interrupt_type imask_irq_type = {
.typename = "SR.IMASK",
.startup = startup_imask_irq,
.shutdown = shutdown_imask_irq,
.enable = enable_imask_irq,
.disable = disable_imask_irq,
.ack = mask_and_ack_imask,
.end = end_imask_irq
};
void static inline set_interrupt_registers(int ip)
{
unsigned long __dummy;
asm volatile("ldc %2, r6_bank\n\t"
"stc sr, %0\n\t"
"and #0xf0, %0\n\t"
"shlr2 %0\n\t"
"cmp/eq #0x3c, %0\n\t"
"bt/s 1f ! CLI-ed\n\t"
" stc sr, %0\n\t"
"and %1, %0\n\t"
"or %2, %0\n\t"
"ldc %0, sr\n"
"1:"
: "=&z" (__dummy)
: "r" (~0xf0), "r" (ip << 4)
: "t");
}
static void disable_imask_irq(unsigned int irq)
{
clear_bit(irq, &imask_mask);
if (interrupt_priority < IMASK_PRIORITY - irq)
interrupt_priority = IMASK_PRIORITY - irq;
set_interrupt_registers(interrupt_priority);
}
static void enable_imask_irq(unsigned int irq)
{
set_bit(irq, &imask_mask);
interrupt_priority = IMASK_PRIORITY - ffz(imask_mask);
set_interrupt_registers(interrupt_priority);
}
static void mask_and_ack_imask(unsigned int irq)
{
disable_imask_irq(irq);
}
static void end_imask_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
enable_imask_irq(irq);
}
static void shutdown_imask_irq(unsigned int irq)
{
/* Nothing to do */
}
void make_imask_irq(unsigned int irq)
{
disable_irq_nosync(irq);
irq_desc[irq].chip = &imask_irq_type;
enable_irq(irq);
}