X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fgenapic-xen.c;fp=arch%2Fx86_64%2Fkernel%2Fgenapic-xen.c;h=1903a5c3e9c8aeebcedee57c9e1301bd5a023841;hb=1db395853d4f30d6120458bd279ede1f882a8525;hp=0000000000000000000000000000000000000000;hpb=34a75f0025b9cf803b6a88db032e6ad6950c9313;p=linux-2.6.git

diff --git a/arch/x86_64/kernel/genapic-xen.c b/arch/x86_64/kernel/genapic-xen.c
new file mode 100644
index 000000000..1903a5c3e
--- /dev/null
+++ b/arch/x86_64/kernel/genapic-xen.c
@@ -0,0 +1,144 @@
+/*
+ * Copyright 2004 James Cleverdon, IBM.
+ * Subject to the GNU Public License, v.2
+ *
+ * Generic APIC sub-arch probe layer.
+ *
+ * Hacked for x86-64 by James Cleverdon from i386 architecture code by
+ * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
+ * James Cleverdon.
+ */
+#include <linux/config.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/smp.h>
+#include <asm/ipi.h>
+
+#if defined(CONFIG_ACPI)
+#include <acpi/acpi_bus.h>
+#endif
+
+/* which logical CPU number maps to which CPU (physical APIC ID) */
+u8 x86_cpu_to_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
+EXPORT_SYMBOL(x86_cpu_to_apicid);
+u8 x86_cpu_to_log_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
+
+extern struct genapic apic_cluster;
+extern struct genapic apic_flat;
+extern struct genapic apic_physflat;
+
+#ifndef CONFIG_XEN
+struct genapic *genapic = &apic_flat;
+#else
+extern struct genapic apic_xen;
+struct genapic *genapic = &apic_xen;
+#endif
+
+
+/*
+ * Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
+ */
+void __init clustered_apic_check(void)
+{
+#ifndef CONFIG_XEN
+	long i;
+	u8 clusters, max_cluster;
+	u8 id;
+	u8 cluster_cnt[NUM_APIC_CLUSTERS];
+	int max_apic = 0;
+
+#if defined(CONFIG_ACPI)
+	/*
+	 * Some x86_64 machines use physical APIC mode regardless of how many
+	 * procs/clusters are present (x86_64 ES7000 is an example).
+	 */
+	if (acpi_fadt.revision > FADT2_REVISION_ID)
+		if (acpi_fadt.force_apic_physical_destination_mode) {
+			genapic = &apic_cluster;
+			goto print;
+		}
+#endif
+
+	memset(cluster_cnt, 0, sizeof(cluster_cnt));
+	for (i = 0; i < NR_CPUS; i++) {
+		id = bios_cpu_apicid[i];
+		if (id == BAD_APICID)
+			continue;
+		if (id > max_apic)
+			max_apic = id;
+		cluster_cnt[APIC_CLUSTERID(id)]++;
+	}
+
+	/* Don't use clustered mode on AMD platforms. */
+ 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
+		genapic = &apic_physflat;
+#ifndef CONFIG_HOTPLUG_CPU
+		/* In the CPU hotplug case we cannot use broadcast mode
+		   because that opens a race when a CPU is removed.
+		   Stay at physflat mode in this case.
+		   It is bad to do this unconditionally though. Once
+		   we have ACPI platform support for CPU hotplug
+		   we should detect hotplug capablity from ACPI tables and
+		   only do this when really needed. -AK */
+		if (max_apic <= 8)
+			genapic = &apic_flat;
+#endif
+ 		goto print;
+ 	}
+
+	clusters = 0;
+	max_cluster = 0;
+
+	for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
+		if (cluster_cnt[i] > 0) {
+			++clusters;
+			if (cluster_cnt[i] > max_cluster)
+				max_cluster = cluster_cnt[i];
+		}
+	}
+
+	/*
+	 * If we have clusters <= 1 and CPUs <= 8 in cluster 0, then flat mode,
+	 * else if max_cluster <= 4 and cluster_cnt[15] == 0, clustered logical
+	 * else physical mode.
+	 * (We don't use lowest priority delivery + HW APIC IRQ steering, so
+	 * can ignore the clustered logical case and go straight to physical.)
+	 */
+	if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster) {
+#ifdef CONFIG_HOTPLUG_CPU
+		/* Don't use APIC shortcuts in CPU hotplug to avoid races */
+		genapic = &apic_physflat;
+#else
+		genapic = &apic_flat;
+#endif
+	} else
+		genapic = &apic_cluster;
+
+print:
+#else
+	/* hardcode to xen apic functions */
+	genapic = &apic_xen;
+#endif
+	printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
+}
+
+/* Same for both flat and clustered. */
+
+#ifdef CONFIG_XEN
+extern void xen_send_IPI_shortcut(unsigned int shortcut, int vector, unsigned int dest);
+#endif
+
+void send_IPI_self(int vector)
+{
+#ifndef CONFIG_XEN
+	__send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
+#else
+	xen_send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
+#endif
+}