x86: parsing for ACPI "SAPIC" table

Add kernel support for new ACPI "sapic" tables that contain 16-bit APICIDs.
This patch simply adds parsing of an optional SAPIC table if present.
Otherwise, the traditional local APIC table is used.

Note: the SAPIC table is not a new ACPI table - it exists on other architectures
but is not currently recognized by x86_64.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 05878ac..b33ebf6 100644 (file)
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -264,6 +264,24 @@ acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end)
        return 0;
 }
 
+static int __init
+acpi_parse_sapic(struct acpi_subtable_header *header, const unsigned long end)
+{
+       struct acpi_madt_local_sapic *processor = NULL;
+
+       processor = (struct acpi_madt_local_sapic *)header;
+
+       if (BAD_MADT_ENTRY(processor, end))
+               return -EINVAL;
+
+       acpi_table_print_madt_entry(header);
+
+       mp_register_lapic((processor->id << 8) | processor->eid,/* APIC ID */
+               processor->lapic_flags & ACPI_MADT_ENABLED);    /* Enabled? */
+
+       return 0;
+}
+
 static int __init
 acpi_parse_lapic_addr_ovr(struct acpi_subtable_header * header,
                          const unsigned long end)
@@ -757,8 +775,12 @@ static int __init acpi_parse_madt_lapic_entries(void)
 
        mp_register_lapic_address(acpi_lapic_addr);
 
-       count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC, acpi_parse_lapic,
-                                     MAX_APICS);
+       count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_SAPIC,
+                                     acpi_parse_sapic, MAX_APICS);
+
+       if (!count)
+               count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC,
+                                             acpi_parse_lapic, MAX_APICS);
        if (!count) {
                printk(KERN_ERR PREFIX "No LAPIC entries present\n");
                /* TBD: Cleanup to allow fallback to MPS */