1 files changed, 74 insertions, 18 deletions

diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 45bd17313c4a..c3419182c9a7 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -42,7 +42,9 @@ static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
 
 static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
 
-void acpi_table_print_madt_entry(struct acpi_subtable_header * header)
+static int acpi_apic_instance __initdata;
+
+void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
 {
 	if (!header)
 		return;
@@ -169,40 +171,42 @@ void acpi_table_print_madt_entry(struct acpi_subtable_header * header)
 
 
 int __init
-acpi_table_parse_madt_family(char *id,
-			     unsigned long madt_size,
+acpi_table_parse_entries(char *id,
+			     unsigned long table_size,
 			     int entry_id,
-			     acpi_madt_entry_handler handler,
+			     acpi_table_entry_handler handler,
 			     unsigned int max_entries)
 {
-	struct acpi_table_header *madt = NULL;
+	struct acpi_table_header *table_header = NULL;
 	struct acpi_subtable_header *entry;
 	unsigned int count = 0;
-	unsigned long madt_end;
+	unsigned long table_end;
 
 	if (!handler)
 		return -EINVAL;
 
-	/* Locate the MADT (if exists). There should only be one. */
-	acpi_get_table(id, 0, &madt);
+	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
+		acpi_get_table(id, acpi_apic_instance, &table_header);
+	else
+		acpi_get_table(id, 0, &table_header);
 
-	if (!madt) {
+	if (!table_header) {
 		printk(KERN_WARNING PREFIX "%4.4s not present\n", id);
 		return -ENODEV;
 	}
 
-	madt_end = (unsigned long)madt + madt->length;
+	table_end = (unsigned long)table_header + table_header->length;
 
 	/* Parse all entries looking for a match. */
 
 	entry = (struct acpi_subtable_header *)
-	    ((unsigned long)madt + madt_size);
+	    ((unsigned long)table_header + table_size);
 
 	while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
-	       madt_end) {
+	       table_end) {
 		if (entry->type == entry_id
 		    && (!max_entries || count++ < max_entries))
-			if (handler(entry, madt_end))
+			if (handler(entry, table_end))
 				return -EINVAL;
 
 		entry = (struct acpi_subtable_header *)
@@ -218,25 +222,64 @@ acpi_table_parse_madt_family(char *id,
 
 int __init
 acpi_table_parse_madt(enum acpi_madt_type id,
-		      acpi_madt_entry_handler handler, unsigned int max_entries)
+		      acpi_table_entry_handler handler, unsigned int max_entries)
 {
-	return acpi_table_parse_madt_family(ACPI_SIG_MADT,
+	return acpi_table_parse_entries(ACPI_SIG_MADT,
 					    sizeof(struct acpi_table_madt), id,
 					    handler, max_entries);
 }
 
+/**
+ * acpi_table_parse - find table with @id, run @handler on it
+ *
+ * @id: table id to find
+ * @handler: handler to run
+ *
+ * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
+ * run @handler on it.  Return 0 if table found, return on if not.
+ */
 int __init acpi_table_parse(char *id, acpi_table_handler handler)
 {
 	struct acpi_table_header *table = NULL;
+
 	if (!handler)
 		return -EINVAL;
 
-	acpi_get_table(id, 0, &table);
+	if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
+		acpi_get_table(id, acpi_apic_instance, &table);
+	else
+		acpi_get_table(id, 0, &table);
+
 	if (table) {
 		handler(table);
+		return 0;
+	} else
 		return 1;
+}
+
+/* 
+ * The BIOS is supposed to supply a single APIC/MADT,
+ * but some report two.  Provide a knob to use either.
+ * (don't you wish instance 0 and 1 were not the same?)
+ */
+static void __init check_multiple_madt(void)
+{
+	struct acpi_table_header *table = NULL;
+
+	acpi_get_table(ACPI_SIG_MADT, 2, &table);
+	if (table) {
+		printk(KERN_WARNING PREFIX
+		       "BIOS bug: multiple APIC/MADT found,"
+		       " using %d\n", acpi_apic_instance);
+		printk(KERN_WARNING PREFIX
+		       "If \"acpi_apic_instance=%d\" works better, "
+		       "notify linux-acpi@vger.kernel.org\n",
+		       acpi_apic_instance ? 0 : 2);
+
 	} else
-		return 0;
+		acpi_apic_instance = 0;
+
+	return;
 }
 
 /*
@@ -248,9 +291,22 @@ int __init acpi_table_parse(char *id, acpi_table_handler handler)
  * result: sdt_entry[] is initialized
  */
 
-
 int __init acpi_table_init(void)
 {
 	acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
+	check_multiple_madt();
+	return 0;
+}
+
+static int __init acpi_parse_apic_instance(char *str)
+{
+
+	acpi_apic_instance = simple_strtoul(str, NULL, 0);
+
+	printk(KERN_NOTICE PREFIX "Shall use APIC/MADT table %d\n",
+	       acpi_apic_instance);
+
 	return 0;
 }
+
+early_param("acpi_apic_instance", acpi_parse_apic_instance);