x86/apic: Add separate apic_id_valid() functions for selected apic drivers

As suggested by Suresh Siddha and Yinghai Lu:

For x2apic pre-enabled systems, apic driver is set already early
through early_acpi_boot_init()/early_acpi_process_madt()/
acpi_parse_madt()/default_acpi_madt_oem_check() path so that
apic_id_valid() checking will be sufficient during MADT and SRAT
parsing.

For non-x2apic pre-enabled systems, all apic ids should be less
than 255.

This allows us to substitute the checks in
arch/x86/kernel/acpi/boot.c::acpi_parse_x2apic() and
arch/x86/mm/srat.c::acpi_numa_x2apic_affinity_init() with
apic->apic_id_valid().

In addition we can avoid feigning the x2apic cpu feature in the
NumaChip apic code.

The following apic drivers have separate apic_id_valid()
functions which will accept x2apic type IDs :

 x2apic_phys
 x2apic_cluster
 x2apic_uv_x
 apic_numachip

Signed-off-by: Steffen Persvold <sp@numascale.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/1331925935-13372-1-git-send-email-sp@numascale.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/apic.h

@@ -535,7 +535,7 @@ static inline unsigned int read_apic_id(void)
 
 static inline int default_apic_id_valid(int apicid)
 {
-	return x2apic_mode || (apicid < 255);
+	return (apicid < 255);
 }
 
 extern void default_setup_apic_routing(void);

arch/x86/include/asm/x2apic.h

@@ -18,6 +18,11 @@ static const struct cpumask *x2apic_target_cpus(void)
 	return cpu_online_mask;
 }
 
+static int x2apic_apic_id_valid(int apicid)
+{
+	return 1;
+}
+
 static int x2apic_apic_id_registered(void)
 {
 	return 1;

arch/x86/kernel/acpi/boot.c

@@ -239,7 +239,7 @@ acpi_parse_x2apic(struct acpi_subtable_header *header, const unsigned long end)
 	 * to not preallocating memory for all NR_CPUS
 	 * when we use CPU hotplug.
 	 */
-	if (!cpu_has_x2apic && (apic_id >= 0xff) && enabled)
+	if (!apic->apic_id_valid(apic_id) && enabled)
 		printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
 	else
 		acpi_register_lapic(apic_id, enabled);

arch/x86/kernel/apic/apic_numachip.c

@@ -229,11 +229,10 @@ static int __init numachip_system_init(void)
 }
 early_initcall(numachip_system_init);
 
-static int __cpuinit numachip_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
+static int numachip_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 {
 	if (!strncmp(oem_id, "NUMASC", 6)) {
 		numachip_system = 1;
-		setup_force_cpu_cap(X86_FEATURE_X2APIC);
 		return 1;
 	}
 

arch/x86/kernel/apic/x2apic_cluster.c

@@ -213,7 +213,7 @@ static struct apic apic_x2apic_cluster = {
 	.name				= "cluster x2apic",
 	.probe				= x2apic_cluster_probe,
 	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
-	.apic_id_valid			= default_apic_id_valid,
+	.apic_id_valid			= x2apic_apic_id_valid,
 	.apic_id_registered		= x2apic_apic_id_registered,
 
 	.irq_delivery_mode		= dest_LowestPrio,

arch/x86/kernel/apic/x2apic_phys.c

@@ -119,7 +119,7 @@ static struct apic apic_x2apic_phys = {
 	.name				= "physical x2apic",
 	.probe				= x2apic_phys_probe,
 	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
-	.apic_id_valid			= default_apic_id_valid,
+	.apic_id_valid			= x2apic_apic_id_valid,
 	.apic_id_registered		= x2apic_apic_id_registered,
 
 	.irq_delivery_mode		= dest_Fixed,

arch/x86/kernel/apic/x2apic_uv_x.c

@@ -266,6 +266,11 @@ static void uv_send_IPI_all(int vector)
 	uv_send_IPI_mask(cpu_online_mask, vector);
 }
 
+static int uv_apic_id_valid(int apicid)
+{
+	return 1;
+}
+
 static int uv_apic_id_registered(void)
 {
 	return 1;
@@ -351,7 +356,7 @@ static struct apic __refdata apic_x2apic_uv_x = {
 	.name				= "UV large system",
 	.probe				= uv_probe,
 	.acpi_madt_oem_check		= uv_acpi_madt_oem_check,
-	.apic_id_valid			= default_apic_id_valid,
+	.apic_id_valid			= uv_apic_id_valid,
 	.apic_id_registered		= uv_apic_id_registered,
 
 	.irq_delivery_mode		= dest_Fixed,

arch/x86/mm/srat.c

@@ -70,7 +70,7 @@ acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa)
 		return;
 	pxm = pa->proximity_domain;
 	apic_id = pa->apic_id;
-	if (!cpu_has_x2apic && (apic_id >= 0xff)) {
+	if (!apic->apic_id_valid(apic_id)) {
 		printk(KERN_INFO "SRAT: PXM %u -> X2APIC 0x%04x ignored\n",
 			 pxm, apic_id);
 		return;