5 * Copyright 2004 James Cleverdon, IBM.
6 * Subject to the GNU Public License, v.2
8 * Generic APIC InterProcessor Interrupt code.
10 * Moved to include file by James Cleverdon from
11 * arch/x86-64/kernel/smp.c
13 * Copyrights from kernel/smp.c:
15 * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
16 * (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com>
17 * (c) 2002,2003 Andi Kleen, SuSE Labs.
18 * Subject to the GNU Public License, v.2
21 #include <asm/fixmap.h>
22 #include <asm/hw_irq.h>
23 #include <asm/apicdef.h>
24 #include <asm/genapic.h>
27 * the following functions deal with sending IPIs between CPUs.
29 * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
32 static inline unsigned int __prepare_ICR (unsigned int shortcut, int vector, unsigned int dest)
34 unsigned int icr = shortcut | dest;
38 icr |= APIC_DM_FIXED | vector;
47 static inline int __prepare_ICR2 (unsigned int mask)
49 return SET_APIC_DEST_FIELD(mask);
52 #ifndef CONFIG_XEN_UNPRIVILEGED_GUEST
53 static inline void __send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest)
56 * Subtle. In the case of the 'never do double writes' workaround
57 * we have to lock out interrupts to be safe. As we don't care
58 * of the value read we use an atomic rmw access to avoid costly
59 * cli/sti. Otherwise we use an even cheaper single atomic write
70 * No need to touch the target chip field
72 cfg = __prepare_ICR(shortcut, vector, dest);
75 * Send the IPI. The write to APIC_ICR fires this off.
77 apic_write(APIC_ICR, cfg);
81 static inline void send_IPI_mask_sequence(cpumask_t mask, int vector)
83 unsigned long cfg, flags;
84 unsigned long query_cpu;
87 * Hack. The clustered APIC addressing mode doesn't allow us to send
88 * to an arbitrary mask, so I do a unicast to each CPU instead.
91 local_irq_save(flags);
93 for_each_cpu_mask(query_cpu, mask) {
100 * prepare target chip field
102 cfg = __prepare_ICR2(x86_cpu_to_apicid[query_cpu]);
103 apic_write(APIC_ICR2, cfg);
108 cfg = __prepare_ICR(0, vector, APIC_DEST_PHYSICAL);
111 * Send the IPI. The write to APIC_ICR fires this off.
113 apic_write(APIC_ICR, cfg);
115 local_irq_restore(flags);
117 #endif /* CONFIG_XEN_UNPRIVILEGED_GUEST */
119 #endif /* __ASM_IPI_H */