x86, ACPI: add support for x2apic ACPI extensions

All logical processors with APIC ID values of 255 and greater will have their
APIC reported through Processor X2APIC structure (type-9 entry type) and all
logical processors with APIC ID less than 255 will have their APIC reported
through legacy Processor Local APIC (type-0 entry type) only. This is the
same case even for NMI structure reporting.
    
The Processor X2APIC Affinity structure provides the association between the
X2APIC ID of a logical processor and the proximity domain to which the logical
processor belongs.
    
For OSPM, Procssor IDs outside the 0-254 range are to be declared as Device()
objects in the ACPI namespace.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 59 insertions, 4 deletions

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 7678f10c4568..565e70c7ca93 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -260,6 +260,35 @@ static void __cpuinit acpi_register_lapic(int id, u8 enabled)
 }
 
 static int __init
+acpi_parse_x2apic(struct acpi_subtable_header *header, const unsigned long end)
+{
+	struct acpi_madt_local_x2apic *processor = NULL;
+
+	processor = (struct acpi_madt_local_x2apic *)header;
+
+	if (BAD_MADT_ENTRY(processor, end))
+		return -EINVAL;
+
+	acpi_table_print_madt_entry(header);
+
+#ifdef CONFIG_X86_X2APIC
+	/*
+	 * We need to register disabled CPU as well to permit
+	 * counting disabled CPUs. This allows us to size
+	 * cpus_possible_map more accurately, to permit
+	 * to not preallocating memory for all NR_CPUS
+	 * when we use CPU hotplug.
+	 */
+	acpi_register_lapic(processor->local_apic_id,	/* APIC ID */
+			    processor->lapic_flags & ACPI_MADT_ENABLED);
+#else
+	printk(KERN_WARNING PREFIX "x2apic entry ignored\n");
+#endif
+
+	return 0;
+}
+
+static int __init
 acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end)
 {
 	struct acpi_madt_local_apic *processor = NULL;
@@ -319,6 +348,25 @@ acpi_parse_lapic_addr_ovr(struct acpi_subtable_header * header,
 }
 
 static int __init
+acpi_parse_x2apic_nmi(struct acpi_subtable_header *header,
+		      const unsigned long end)
+{
+	struct acpi_madt_local_x2apic_nmi *x2apic_nmi = NULL;
+
+	x2apic_nmi = (struct acpi_madt_local_x2apic_nmi *)header;
+
+	if (BAD_MADT_ENTRY(x2apic_nmi, end))
+		return -EINVAL;
+
+	acpi_table_print_madt_entry(header);
+
+	if (x2apic_nmi->lint != 1)
+		printk(KERN_WARNING PREFIX "NMI not connected to LINT 1!\n");
+
+	return 0;
+}
+
+static int __init
 acpi_parse_lapic_nmi(struct acpi_subtable_header * header, const unsigned long end)
 {
 	struct acpi_madt_local_apic_nmi *lapic_nmi = NULL;
@@ -823,6 +871,7 @@ static int __init early_acpi_parse_madt_lapic_addr_ovr(void)
 static int __init acpi_parse_madt_lapic_entries(void)
 {
 	int count;
+	int x2count = 0;
 
 	if (!cpu_has_apic)
 		return -ENODEV;
@@ -846,22 +895,28 @@ static int __init acpi_parse_madt_lapic_entries(void)
 	count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_SAPIC,
 				      acpi_parse_sapic, MAX_APICS);
 
-	if (!count)
+	if (!count) {
+		x2count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_X2APIC,
+						acpi_parse_x2apic, MAX_APICS);
 		count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC,
 					      acpi_parse_lapic, MAX_APICS);
-	if (!count) {
+	}
+	if (!count && !x2count) {
 		printk(KERN_ERR PREFIX "No LAPIC entries present\n");
 		/* TBD: Cleanup to allow fallback to MPS */
 		return -ENODEV;
-	} else if (count < 0) {
+	} else if (count < 0 || x2count < 0) {
 		printk(KERN_ERR PREFIX "Error parsing LAPIC entry\n");
 		/* TBD: Cleanup to allow fallback to MPS */
 		return count;
 	}
 
+	x2count =
+	    acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_X2APIC_NMI,
+				  acpi_parse_x2apic_nmi, 0);
 	count =
 	    acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_NMI, acpi_parse_lapic_nmi, 0);
-	if (count < 0) {
+	if (count < 0 || x2count < 0) {
 		printk(KERN_ERR PREFIX "Error parsing LAPIC NMI entry\n");
 		/* TBD: Cleanup to allow fallback to MPS */
 		return count;