kernel-fxtec-pro1x/arch/sparc/include/asm/irqflags_64.h
David S. Miller c011f80ba0 sparc64: Add some more commentary to __raw_local_irq_save()
Suggested by Peter Zijlstra

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-04-13 01:50:43 -07:00

108 lines
2 KiB
C

/*
* include/asm/irqflags.h
*
* IRQ flags handling
*
* This file gets included from lowlevel asm headers too, to provide
* wrapped versions of the local_irq_*() APIs, based on the
* raw_local_irq_*() functions from the lowlevel headers.
*/
#ifndef _ASM_IRQFLAGS_H
#define _ASM_IRQFLAGS_H
#include <asm/pil.h>
#ifndef __ASSEMBLY__
static inline unsigned long __raw_local_save_flags(void)
{
unsigned long flags;
__asm__ __volatile__(
"rdpr %%pil, %0"
: "=r" (flags)
);
return flags;
}
#define raw_local_save_flags(flags) \
do { (flags) = __raw_local_save_flags(); } while (0)
static inline void raw_local_irq_restore(unsigned long flags)
{
__asm__ __volatile__(
"wrpr %0, %%pil"
: /* no output */
: "r" (flags)
: "memory"
);
}
static inline void raw_local_irq_disable(void)
{
__asm__ __volatile__(
"wrpr %0, %%pil"
: /* no outputs */
: "i" (PIL_NORMAL_MAX)
: "memory"
);
}
static inline void raw_local_irq_enable(void)
{
__asm__ __volatile__(
"wrpr 0, %%pil"
: /* no outputs */
: /* no inputs */
: "memory"
);
}
static inline int raw_irqs_disabled_flags(unsigned long flags)
{
return (flags > 0);
}
static inline int raw_irqs_disabled(void)
{
unsigned long flags = __raw_local_save_flags();
return raw_irqs_disabled_flags(flags);
}
/*
* For spinlocks, etc:
*/
static inline unsigned long __raw_local_irq_save(void)
{
unsigned long flags, tmp;
/* Disable interrupts to PIL_NORMAL_MAX unless we already
* are using PIL_NMI, in which case PIL_NMI is retained.
*
* The only values we ever program into the %pil are 0,
* PIL_NORMAL_MAX and PIL_NMI.
*
* Since PIL_NMI is the largest %pil value and all bits are
* set in it (0xf), it doesn't matter what PIL_NORMAL_MAX
* actually is.
*/
__asm__ __volatile__(
"rdpr %%pil, %0\n\t"
"or %0, %2, %1\n\t"
"wrpr %1, 0x0, %%pil"
: "=r" (flags), "=r" (tmp)
: "i" (PIL_NORMAL_MAX)
: "memory"
);
return flags;
}
#define raw_local_irq_save(flags) \
do { (flags) = __raw_local_irq_save(); } while (0)
#endif /* (__ASSEMBLY__) */
#endif /* !(_ASM_IRQFLAGS_H) */