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-rw-r--r--arch/x86/include/asm/ipi.h138
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diff --git a/arch/x86/include/asm/ipi.h b/arch/x86/include/asm/ipi.h
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+++ b/arch/x86/include/asm/ipi.h
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+#ifndef ASM_X86__IPI_H
+#define ASM_X86__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>
+#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 __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 __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);
+}
+
+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_nr(query_cpu, mask) {
+ __send_IPI_dest_field(per_cpu(x86_cpu_to_apicid, query_cpu),
+ vector, APIC_DEST_PHYSICAL);
+ }
+ local_irq_restore(flags);
+}
+
+#endif /* ASM_X86__IPI_H */