ipi.h

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#ifndef _ASM_X86_IPI_H
#define _ASM_X86_IPI_H

#ifdef CONFIG_X86_LOCAL_APIC

/*
 * Copyright 2004 James Cleverdon, IBM.
 * Subject to the GNU Public License, v.2
 *
 * Generic APIC InterProcessor Interrupt code.
 *
 * Moved to include file by James Cleverdon from
 * arch/x86-64/kernel/smp.c
 *
 * Copyrights from kernel/smp.c:
 *
 * (c) 1995 Alan Cox, Building #3 <[email protected]>
 * (c) 1998-99, 2000 Ingo Molnar <[email protected]>
 * (c) 2002,2003 Andi Kleen, SuSE Labs.
 * Subject to the GNU Public License, v.2
 */

#include <asm/hw_irq.h>
#include <asm/apic.h>
#include <asm/smp.h>

/*
 * the following functions deal with sending IPIs between CPUs.
 *
 * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
 */

static inline unsigned int __prepare_ICR(unsigned int shortcut, int vector,
                     unsigned int dest)
{
    unsigned int icr = shortcut | dest;

    switch (vector) {
    default:
        icr |= APIC_DM_FIXED | vector;
        break;
    case NMI_VECTOR:
        icr |= APIC_DM_NMI;
        break;
    }
    return icr;
}

static inline int __prepare_ICR2(unsigned int mask)
{
    return SET_APIC_DEST_FIELD(mask);
}

static inline void __xapic_wait_icr_idle(void)
{
    while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
        cpu_relax();
}

static inline void
__default_send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest)
{
    /*
     * Subtle. In the case of the 'never do double writes' workaround
     * we have to lock out interrupts to be safe.  As we don't care
     * of the value read we use an atomic rmw access to avoid costly
     * cli/sti.  Otherwise we use an even cheaper single atomic write
     * to the APIC.
     */
    unsigned int cfg;

    /*
     * Wait for idle.
     */
    __xapic_wait_icr_idle();

    /*
     * No need to touch the target chip field
     */
    cfg = __prepare_ICR(shortcut, vector, dest);

    /*
     * Send the IPI. The write to APIC_ICR fires this off.
     */
    native_apic_mem_write(APIC_ICR, cfg);
}

/*
 * This is used to send an IPI with no shorthand notation (the destination is
 * specified in bits 56 to 63 of the ICR).
 */
static inline void
 __default_send_IPI_dest_field(unsigned int mask, int vector, unsigned int dest)
{
    unsigned long cfg;

    /*
     * Wait for idle.
     */
    if (unlikely(vector == NMI_VECTOR))
        safe_apic_wait_icr_idle();
    else
        __xapic_wait_icr_idle();

    /*
     * prepare target chip field
     */
    cfg = __prepare_ICR2(mask);
    native_apic_mem_write(APIC_ICR2, cfg);

    /*
     * program the ICR
     */
    cfg = __prepare_ICR(0, vector, dest);

    /*
     * Send the IPI. The write to APIC_ICR fires this off.
     */
    native_apic_mem_write(APIC_ICR, cfg);
}

extern void default_send_IPI_mask_sequence_phys(const struct cpumask *mask,
                         int vector);
extern void default_send_IPI_mask_allbutself_phys(const struct cpumask *mask,
                             int vector);

/* Avoid include hell */
#define NMI_VECTOR 0x02

extern int no_broadcast;

static inline void __default_local_send_IPI_allbutself(int vector)
{
    if (no_broadcast || vector == NMI_VECTOR)
        apic->send_IPI_mask_allbutself(cpu_online_mask, vector);
    else
        __default_send_IPI_shortcut(APIC_DEST_ALLBUT, vector, apic->dest_logical);
}

static inline void __default_local_send_IPI_all(int vector)
{
    if (no_broadcast || vector == NMI_VECTOR)
        apic->send_IPI_mask(cpu_online_mask, vector);
    else
        __default_send_IPI_shortcut(APIC_DEST_ALLINC, vector, apic->dest_logical);
}

#ifdef CONFIG_X86_32
extern void default_send_IPI_mask_sequence_logical(const struct cpumask *mask,
                             int vector);
extern void default_send_IPI_mask_allbutself_logical(const struct cpumask *mask,
                             int vector);
extern void default_send_IPI_mask_logical(const struct cpumask *mask,
                         int vector);
extern void default_send_IPI_allbutself(int vector);
extern void default_send_IPI_all(int vector);
extern void default_send_IPI_self(int vector);
#endif

#endif

#endif /* _ASM_X86_IPI_H */