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Diffstat (limited to 'include/asm-x86_64/ipi.h')
-rw-r--r-- | include/asm-x86_64/ipi.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/include/asm-x86_64/ipi.h b/include/asm-x86_64/ipi.h new file mode 100644 index 00000000000..d1841847ed8 --- /dev/null +++ b/include/asm-x86_64/ipi.h @@ -0,0 +1,113 @@ +#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 */ |