---

yaml --- r: 241685 b: refs/heads/master c: 64b3db2 h: refs/heads/master i: 241683: 6908bc8 v: v3
git-mirror · Mar 3, 2011 · 12caf4e · 12caf4e
1 parent dfad22a
commit 12caf4e
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Showing 3 changed files with 21 additions and 2 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6dfad339645247c9deb553e4d68e21211ddc61bd
+refs/heads/master: 64b3db22c04586997ab4be46dd5a5b99f8a2d390
diff --git a/trunk/drivers/acpi/acpica/tbfadt.c b/trunk/drivers/acpi/acpica/tbfadt.c
@@ -384,8 +384,11 @@ static void acpi_tb_convert_fadt(void)
 	 *
 	 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located at
 	 * offset 45, 55, 95, and the word located at offset 109, 110.
+	 *
+	 * Note: The FADT revision value is unreliable. Only the length can be
+	 * trusted.
 	 */
-	if (acpi_gbl_FADT.header.revision < FADT2_REVISION_ID) {
+	if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {
 		acpi_gbl_FADT.preferred_profile = 0;
 		acpi_gbl_FADT.pstate_control = 0;
 		acpi_gbl_FADT.cst_control = 0;

diff --git a/trunk/include/acpi/actbl.h b/trunk/include/acpi/actbl.h
@@ -343,4 +343,20 @@ struct acpi_table_desc {
 #include <acpi/actbl1.h>
 #include <acpi/actbl2.h>
 
+/*
+ * Sizes of the various flavors of FADT. We need to look closely
+ * at the FADT length because the version number essentially tells
+ * us nothing because of many BIOS bugs where the version does not
+ * match the expected length. In other words, the length of the
+ * FADT is the bottom line as to what the version really is.
+ *
+ * For reference, the values below are as follows:
+ *     FADT V1  size: 0x74
+ *     FADT V2  size: 0x84
+ *     FADT V3+ size: 0xF4
+ */
+#define ACPI_FADT_V1_SIZE       (u32) (ACPI_FADT_OFFSET (flags) + 4)
+#define ACPI_FADT_V2_SIZE       (u32) (ACPI_FADT_OFFSET (reserved4[0]) + 3)
+#define ACPI_FADT_V3_SIZE       (u32) (sizeof (struct acpi_table_fadt))
+
 #endif				/* __ACTBL_H__ */