X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fgenapic.c;h=f3159a496e39ca2c6136b6bae47c72ecb11d1371;hb=413588c7cb8113c03d0044f1d41b832ad7201c29;hp=69b9c25a8fc4ee5399b76b4a5d0967fc9c520f33;hpb=90660ec3c3e3f463a3cc7005213345b6c9ecfab9;p=pandora-kernel.git

diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c
index 69b9c25a8fc4..f3159a496e39 100644
--- a/arch/x86_64/kernel/genapic.c
+++ b/arch/x86_64/kernel/genapic.c
@@ -20,17 +20,18 @@
 #include <asm/smp.h>
 #include <asm/ipi.h>
 
-#if defined(CONFIG_ACPI_BUS)
+#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] = { [0 ... NR_CPUS-1] = BAD_APICID };
+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;
 
 struct genapic *genapic = &apic_flat;
 
@@ -44,14 +45,9 @@ void __init clustered_apic_check(void)
 	u8 clusters, max_cluster;
 	u8 id;
 	u8 cluster_cnt[NUM_APIC_CLUSTERS];
+	int max_apic = 0;
 
-	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
-		/* AMD always uses flat mode right now */
-		genapic = &apic_flat;
-		goto print;
-	}
-
-#if defined(CONFIG_ACPI_BUS)
+#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).
@@ -64,15 +60,35 @@ void __init clustered_apic_check(void)
 #endif
 
 	memset(cluster_cnt, 0, sizeof(cluster_cnt));
-
 	for (i = 0; i < NR_CPUS; i++) {
 		id = bios_cpu_apicid[i];
-		if (id != BAD_APICID)
-			cluster_cnt[APIC_CLUSTERID(id)]++;
+		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_CPU_HOTPLUG
+		/* 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;