irqflags_64.h

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/*
 * 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
 * arch_local_irq_*() functions from the lowlevel headers.
 */
#ifndef _ASM_IRQFLAGS_H
#define _ASM_IRQFLAGS_H

#include <asm/pil.h>

#ifndef __ASSEMBLY__

static inline notrace unsigned long arch_local_save_flags(void)
{
    unsigned long flags;

    __asm__ __volatile__(
        "rdpr   %%pil, %0"
        : "=r" (flags)
    );

    return flags;
}

static inline notrace void arch_local_irq_restore(unsigned long flags)
{
    __asm__ __volatile__(
        "wrpr   %0, %%pil"
        : /* no output */
        : "r" (flags)
        : "memory"
    );
}

static inline notrace void arch_local_irq_disable(void)
{
    __asm__ __volatile__(
        "wrpr   %0, %%pil"
        : /* no outputs */
        : "i" (PIL_NORMAL_MAX)
        : "memory"
    );
}

static inline notrace void arch_local_irq_enable(void)
{
    __asm__ __volatile__(
        "wrpr   0, %%pil"
        : /* no outputs */
        : /* no inputs */
        : "memory"
    );
}

static inline notrace int arch_irqs_disabled_flags(unsigned long flags)
{
    return (flags > 0);
}

static inline notrace int arch_irqs_disabled(void)
{
    return arch_irqs_disabled_flags(arch_local_save_flags());
}

static inline notrace unsigned long arch_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;
}

#endif /* (__ASSEMBLY__) */

#endif /* !(_ASM_IRQFLAGS_H) */