From 8202350367ac11d571f6dd4c21c2027a4d235276 Mon Sep 17 00:00:00 2001
From: Glauber Costa <gcosta@redhat.com>
Date: Mon, 3 Mar 2008 14:12:53 -0300
Subject: x86: create ipi.c

This patch moves all ipi and apic related functions
from smp_32.c to ipi.c

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/x86/kernel/ipi.c | 178 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 178 insertions(+)
 create mode 100644 arch/x86/kernel/ipi.c

(limited to 'arch/x86/kernel/ipi.c')

diff --git a/arch/x86/kernel/ipi.c b/arch/x86/kernel/ipi.c
new file mode 100644
index 00000000000..c0df7b89ca2
--- /dev/null
+++ b/arch/x86/kernel/ipi.c
@@ -0,0 +1,178 @@
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/kernel_stat.h>
+#include <linux/mc146818rtc.h>
+#include <linux/cache.h>
+#include <linux/interrupt.h>
+#include <linux/cpu.h>
+#include <linux/module.h>
+
+#include <asm/smp.h>
+#include <asm/mtrr.h>
+#include <asm/tlbflush.h>
+#include <asm/mmu_context.h>
+#include <asm/apic.h>
+#include <asm/proto.h>
+
+#ifdef CONFIG_X86_32
+#include <mach_apic.h>
+/*
+ * the following functions deal with sending IPIs between CPUs.
+ *
+ * We use 'broadcast', CPU->CPU IPIs and self-IPIs too.
+ */
+
+static inline int __prepare_ICR(unsigned int shortcut, int vector)
+{
+	unsigned int icr = shortcut | APIC_DEST_LOGICAL;
+
+	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);
+}
+
+void __send_IPI_shortcut(unsigned int shortcut, int vector)
+{
+	/*
+	 * 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);
+
+	/*
+	 * Send the IPI. The write to APIC_ICR fires this off.
+	 */
+	apic_write_around(APIC_ICR, cfg);
+}
+
+void send_IPI_self(int vector)
+{
+	__send_IPI_shortcut(APIC_DEST_SELF, vector);
+}
+
+/*
+ * 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 long mask, int vector)
+{
+	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_around(APIC_ICR2, cfg);
+
+	/*
+	 * program the ICR
+	 */
+	cfg = __prepare_ICR(0, vector);
+
+	/*
+	 * Send the IPI. The write to APIC_ICR fires this off.
+	 */
+	apic_write_around(APIC_ICR, cfg);
+}
+
+/*
+ * This is only used on smaller machines.
+ */
+void send_IPI_mask_bitmask(cpumask_t cpumask, int vector)
+{
+	unsigned long mask = cpus_addr(cpumask)[0];
+	unsigned long flags;
+
+	local_irq_save(flags);
+	WARN_ON(mask & ~cpus_addr(cpu_online_map)[0]);
+	__send_IPI_dest_field(mask, vector);
+	local_irq_restore(flags);
+}
+
+void send_IPI_mask_sequence(cpumask_t mask, int vector)
+{
+	unsigned long flags;
+	unsigned int query_cpu;
+
+	/*
+	 * Hack. The clustered APIC addressing mode doesn't allow us to send
+	 * to an arbitrary mask, so I do a unicasts to each CPU instead. This
+	 * should be modified to do 1 message per cluster ID - mbligh
+	 */
+
+	local_irq_save(flags);
+	for_each_possible_cpu(query_cpu) {
+		if (cpu_isset(query_cpu, mask)) {
+			__send_IPI_dest_field(cpu_to_logical_apicid(query_cpu),
+					      vector);
+		}
+	}
+	local_irq_restore(flags);
+}
+
+/* must come after the send_IPI functions above for inlining */
+#include <mach_ipi.h>
+static int convert_apicid_to_cpu(int apic_id)
+{
+	int i;
+
+	for_each_possible_cpu(i) {
+		if (per_cpu(x86_cpu_to_apicid, i) == apic_id)
+			return i;
+	}
+	return -1;
+}
+
+int safe_smp_processor_id(void)
+{
+	int apicid, cpuid;
+
+	if (!boot_cpu_has(X86_FEATURE_APIC))
+		return 0;
+
+	apicid = hard_smp_processor_id();
+	if (apicid == BAD_APICID)
+		return 0;
+
+	cpuid = convert_apicid_to_cpu(apicid);
+
+	return cpuid >= 0 ? cpuid : 0;
+}
+#endif
-- 
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