linux/arch/powerpc/include/asm/hw_irq.h
Benjamin Herrenschmidt 5d38902c48 powerpc: Add irqtrace support for 32-bit powerpc
Based on initial work from: Dale Farnsworth <dale@farnsworth.org>

Add the low level irq tracing hooks for 32-bit powerpc needed
to enable full lockdep functionality.

The approach taken to deal with the code in entry_32.S is that
we don't trace all the transitions of MSR:EE when we just turn
it off to peek at TI_FLAGS without races. Only when we are
calling into C code or returning from exceptions with a state
that have changed from what lockdep thinks.

There's a little bugger though: If we take an exception that
keeps interrupts enabled (such as an alignment exception) while
interrupts are enabled, we will call trace_hardirqs_on() on the
way back spurriously. Not a big deal, but to get rid of it would
require remembering in pt_regs that the exception was one of the
type that kept interrupts enabled which we don't know at this
stage. (Well, we could test all cases for regs->trap but that
sucks too much).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Kumar Gala <galak@kernel.crashing.org>
2009-06-26 14:37:27 +10:00

173 lines
3.8 KiB
C

/*
* Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
*/
#ifndef _ASM_POWERPC_HW_IRQ_H
#define _ASM_POWERPC_HW_IRQ_H
#ifdef __KERNEL__
#include <linux/errno.h>
#include <linux/compiler.h>
#include <asm/ptrace.h>
#include <asm/processor.h>
extern void timer_interrupt(struct pt_regs *);
#ifdef CONFIG_PPC64
#include <asm/paca.h>
static inline unsigned long local_get_flags(void)
{
unsigned long flags;
__asm__ __volatile__("lbz %0,%1(13)"
: "=r" (flags)
: "i" (offsetof(struct paca_struct, soft_enabled)));
return flags;
}
static inline unsigned long raw_local_irq_disable(void)
{
unsigned long flags, zero;
__asm__ __volatile__("li %1,0; lbz %0,%2(13); stb %1,%2(13)"
: "=r" (flags), "=&r" (zero)
: "i" (offsetof(struct paca_struct, soft_enabled))
: "memory");
return flags;
}
extern void raw_local_irq_restore(unsigned long);
extern void iseries_handle_interrupts(void);
#define raw_local_irq_enable() raw_local_irq_restore(1)
#define raw_local_save_flags(flags) ((flags) = local_get_flags())
#define raw_local_irq_save(flags) ((flags) = raw_local_irq_disable())
#define raw_irqs_disabled() (local_get_flags() == 0)
#define raw_irqs_disabled_flags(flags) ((flags) == 0)
#define __hard_irq_enable() __mtmsrd(mfmsr() | MSR_EE, 1)
#define __hard_irq_disable() __mtmsrd(mfmsr() & ~MSR_EE, 1)
#define hard_irq_disable() \
do { \
__hard_irq_disable(); \
get_paca()->soft_enabled = 0; \
get_paca()->hard_enabled = 0; \
} while(0)
static inline int irqs_disabled_flags(unsigned long flags)
{
return flags == 0;
}
#else
#if defined(CONFIG_BOOKE)
#define SET_MSR_EE(x) mtmsr(x)
#define raw_local_irq_restore(flags) __asm__ __volatile__("wrtee %0" : : "r" (flags) : "memory")
#else
#define SET_MSR_EE(x) mtmsr(x)
#define raw_local_irq_restore(flags) mtmsr(flags)
#endif
static inline void raw_local_irq_disable(void)
{
#ifdef CONFIG_BOOKE
__asm__ __volatile__("wrteei 0": : :"memory");
#else
unsigned long msr;
msr = mfmsr();
SET_MSR_EE(msr & ~MSR_EE);
#endif
}
static inline void raw_local_irq_enable(void)
{
#ifdef CONFIG_BOOKE
__asm__ __volatile__("wrteei 1": : :"memory");
#else
unsigned long msr;
msr = mfmsr();
SET_MSR_EE(msr | MSR_EE);
#endif
}
static inline void raw_local_irq_save_ptr(unsigned long *flags)
{
unsigned long msr;
msr = mfmsr();
*flags = msr;
#ifdef CONFIG_BOOKE
__asm__ __volatile__("wrteei 0": : :"memory");
#else
SET_MSR_EE(msr & ~MSR_EE);
#endif
}
#define raw_local_save_flags(flags) ((flags) = mfmsr())
#define raw_local_irq_save(flags) raw_local_irq_save_ptr(&flags)
#define raw_irqs_disabled() ((mfmsr() & MSR_EE) == 0)
#define raw_irqs_disabled_flags(flags) (((flags) & MSR_EE) == 0)
#define hard_irq_disable() raw_local_irq_disable()
static inline int irqs_disabled_flags(unsigned long flags)
{
return (flags & MSR_EE) == 0;
}
#endif /* CONFIG_PPC64 */
/*
* interrupt-retrigger: should we handle this via lost interrupts and IPIs
* or should we not care like we do now ? --BenH.
*/
struct irq_chip;
#ifdef CONFIG_PERF_COUNTERS
#ifdef CONFIG_PPC64
static inline unsigned long test_perf_counter_pending(void)
{
unsigned long x;
asm volatile("lbz %0,%1(13)"
: "=r" (x)
: "i" (offsetof(struct paca_struct, perf_counter_pending)));
return x;
}
static inline void set_perf_counter_pending(void)
{
asm volatile("stb %0,%1(13)" : :
"r" (1),
"i" (offsetof(struct paca_struct, perf_counter_pending)));
}
static inline void clear_perf_counter_pending(void)
{
asm volatile("stb %0,%1(13)" : :
"r" (0),
"i" (offsetof(struct paca_struct, perf_counter_pending)));
}
#endif /* CONFIG_PPC64 */
#else /* CONFIG_PERF_COUNTERS */
static inline unsigned long test_perf_counter_pending(void)
{
return 0;
}
static inline void clear_perf_counter_pending(void) {}
#endif /* CONFIG_PERF_COUNTERS */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_HW_IRQ_H */