x86, um: ... and asm-x86 move

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 138 insertions, 0 deletions

diff --git a/arch/x86/include/asm/ipi.h b/arch/x86/include/asm/ipi.h
new file mode 100644
index 000000000000..30a692cfaff8
--- /dev/null
+++ b/arch/x86/include/asm/ipi.h
@@ -0,0 +1,138 @@
+#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 */