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Diffstat (limited to 'include/asm-x86/ipi.h')
| -rw-r--r-- | include/asm-x86/ipi.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/include/asm-x86/ipi.h b/include/asm-x86/ipi.h new file mode 100644 index 00000000000..a7c75ea408a --- /dev/null +++ b/include/asm-x86/ipi.h @@ -0,0 +1,128 @@ +#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/hw_irq.h> +#include <asm/apic.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 __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(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 __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 + apic_wait_icr_idle(); + + /* + * prepare target chip field + */ + cfg = __prepare_ICR2(mask); + apic_write(APIC_ICR2, cfg); + + /* + * program the ICR + */ + cfg = __prepare_ICR(0, vector, dest); + + /* + * Send the IPI. The write to APIC_ICR fires this off. + */ + apic_write(APIC_ICR, cfg); +} + +static inline void send_IPI_mask_sequence(cpumask_t mask, int vector) +{ + unsigned long 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_each_cpu_mask(query_cpu, mask) { + __send_IPI_dest_field(x86_cpu_to_apicid[query_cpu], + vector, APIC_DEST_PHYSICAL); + } + local_irq_restore(flags); +} + +#endif /* __ASM_IPI_H */ |