#ifndef __ASM_IPI_H
#define __ASM_IPI_H
/*
* 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 <alan@redhat.com>
* (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
* (c) 2002,2003 Andi Kleen, SuSE Labs.
* Subject to the GNU Public License, v.2
*/
#include <asm/fixmap.h>
#include <asm/hw_irq.h>
#include <asm/apicdef.h>
#include <asm/genapic.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 = APIC_DM_FIXED | shortcut | vector | dest;
if (vector == KDB_VECTOR)
icr = (icr & (~APIC_VECTOR_MASK)) | APIC_DM_NMI;
return icr;
}
static inline int __prepare_ICR2 (unsigned int mask)
{
return SET_APIC_DEST_FIELD(mask);
}
static inline void __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.
*/
apic_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.
*/
apic_write_around(APIC_ICR, cfg);
}
static inline void send_IPI_mask_sequence(cpumask_t mask, int vector)
{
unsigned long cfg, flags;
unsigned long query_cpu;
/*
* Hack. The clustered APIC addressing mode doesn't allow us to send
* to an arbitrary mask, so I do a unicast to each CPU instead.
* - mbligh
*/
local_irq_save(flags);
for (query_cpu = 0; query_cpu < NR_CPUS; ++query_cpu) {
if (cpu_isset(query_cpu, mask)) {
/*
* Wait for idle.
*/
apic_wait_icr_idle();
/*
* prepare target chip field
*/
cfg = __prepare_ICR2(x86_cpu_to_apicid[query_cpu]);
apic_write_around(APIC_ICR2, cfg);
/*
* program the ICR
*/
cfg = __prepare_ICR(0, vector, APIC_DEST_PHYSICAL);
/*
* Send the IPI. The write to APIC_ICR fires this off.
*/
apic_write_around(APIC_ICR, cfg);
}
}
local_irq_restore(flags);
}
#endif /* __ASM_IPI_H */
