linux/arch/mips/include/asm/irq.h

165 lines
4.3 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) 1994 by Waldorf GMBH, written by Ralf Baechle
* Copyright (C) 1995, 96, 97, 98, 99, 2000, 01, 02, 03 by Ralf Baechle
*/
#ifndef _ASM_IRQ_H
#define _ASM_IRQ_H
#include <linux/linkage.h>
#include <asm/mipsmtregs.h>
#include <irq.h>
#ifdef CONFIG_I8259
static inline int irq_canonicalize(int irq)
{
return ((irq == I8259A_IRQ_BASE + 2) ? I8259A_IRQ_BASE + 9 : irq);
}
#else
#define irq_canonicalize(irq) (irq) /* Sane hardware, sane code ... */
#endif
#ifdef CONFIG_MIPS_MT_SMTC
struct irqaction;
extern unsigned long irq_hwmask[];
extern int setup_irq_smtc(unsigned int irq, struct irqaction * new,
unsigned long hwmask);
static inline void smtc_im_ack_irq(unsigned int irq)
{
if (irq_hwmask[irq] & ST0_IM)
set_c0_status(irq_hwmask[irq] & ST0_IM);
}
#else
static inline void smtc_im_ack_irq(unsigned int irq)
{
}
#endif /* CONFIG_MIPS_MT_SMTC */
#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
#include <linux/cpumask.h>
extern int plat_set_irq_affinity(unsigned int irq,
const struct cpumask *affinity);
extern void smtc_forward_irq(unsigned int irq);
/*
* IRQ affinity hook invoked at the beginning of interrupt dispatch
* if option is enabled.
*
* Up through Linux 2.6.22 (at least) cpumask operations are very
* inefficient on MIPS. Initial prototypes of SMTC IRQ affinity
* used a "fast path" per-IRQ-descriptor cache of affinity information
* to reduce latency. As there is a project afoot to optimize the
* cpumask implementations, this version is optimistically assuming
* that cpumask.h macro overhead is reasonable during interrupt dispatch.
*/
#define IRQ_AFFINITY_HOOK(irq) \
do { \
if (!cpumask_test_cpu(smp_processor_id(), irq_desc[irq].affinity)) {\
smtc_forward_irq(irq); \
irq_exit(); \
return; \
} \
} while (0)
#else /* Not doing SMTC affinity */
#define IRQ_AFFINITY_HOOK(irq) do { } while (0)
#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */
#ifdef CONFIG_MIPS_MT_SMTC_IM_BACKSTOP
/*
* Clear interrupt mask handling "backstop" if irq_hwmask
* entry so indicates. This implies that the ack() or end()
* functions will take over re-enabling the low-level mask.
* Otherwise it will be done on return from exception.
*/
#define __DO_IRQ_SMTC_HOOK(irq) \
do { \
IRQ_AFFINITY_HOOK(irq); \
if (irq_hwmask[irq] & 0x0000ff00) \
write_c0_tccontext(read_c0_tccontext() & \
~(irq_hwmask[irq] & 0x0000ff00)); \
} while (0)
#define __NO_AFFINITY_IRQ_SMTC_HOOK(irq) \
do { \
if (irq_hwmask[irq] & 0x0000ff00) \
write_c0_tccontext(read_c0_tccontext() & \
~(irq_hwmask[irq] & 0x0000ff00)); \
} while (0)
#else
#define __DO_IRQ_SMTC_HOOK(irq) \
do { \
IRQ_AFFINITY_HOOK(irq); \
} while (0)
#define __NO_AFFINITY_IRQ_SMTC_HOOK(irq) do { } while (0)
#endif
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*
* Ideally there should be away to get this into kernel/irq/handle.c to
* avoid the overhead of a call for just a tiny function ...
*/
#define do_IRQ(irq) \
do { \
irq_enter(); \
__DO_IRQ_SMTC_HOOK(irq); \
generic_handle_irq(irq); \
irq_exit(); \
} while (0)
#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
/*
* To avoid inefficient and in some cases pathological re-checking of
* IRQ affinity, we have this variant that skips the affinity check.
*/
#define do_IRQ_no_affinity(irq) \
do { \
irq_enter(); \
__NO_AFFINITY_IRQ_SMTC_HOOK(irq); \
generic_handle_irq(irq); \
irq_exit(); \
} while (0)
#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */
extern void arch_init_irq(void);
extern void spurious_interrupt(void);
extern int allocate_irqno(void);
extern void alloc_legacy_irqno(void);
extern void free_irqno(unsigned int irq);
/*
* Before R2 the timer and performance counter interrupts were both fixed to
* IE7. Since R2 their number has to be read from the c0_intctl register.
*/
#define CP0_LEGACY_COMPARE_IRQ 7
extern int cp0_compare_irq;
extern int cp0_perfcount_irq;
#endif /* _ASM_IRQ_H */