Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm

[sfrench/cifs-2.6.git] / drivers / acpi / tables / tbfadt.c

diff --git a/drivers/acpi/tables/tbfadt.c b/drivers/acpi/tables/tbfadt.c
index 1db833eb2417c5988890dc8ce4b62bed764e0d45..002bb33003af8c8c30c1b48bfb0607c397d974cf 100644 (file)
--- a/drivers/acpi/tables/tbfadt.c
+++ b/drivers/acpi/tables/tbfadt.c
@@ -211,14 +211,17 @@ void acpi_tb_parse_fadt(acpi_native_uint table_index, u8 flags)
  * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.
  *              Performs validation on some important FADT fields.
  *
+ * NOTE:        We create a local copy of the FADT regardless of the version.
+ *
  ******************************************************************************/
 
 void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
 {
 
        /*
-        * Check if the FADT is larger than what we know about (ACPI 2.0 version).
-        * Truncate the table, but make some noise.
+        * Check if the FADT is larger than the largest table that we expect
+        * (the ACPI 2.0/3.0 version). If so, truncate the table, and issue
+        * a warning.
         */
        if (length > sizeof(struct acpi_table_fadt)) {
                ACPI_WARNING((AE_INFO,
@@ -227,10 +230,12 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
                              sizeof(struct acpi_table_fadt)));
        }
 
-       /* Copy the entire FADT locally. Zero first for tb_convert_fadt */
+       /* Clear the entire local FADT */
 
        ACPI_MEMSET(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));
 
+       /* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */
+
        ACPI_MEMCPY(&acpi_gbl_FADT, table,
                    ACPI_MIN(length, sizeof(struct acpi_table_fadt)));
 
@@ -251,7 +256,7 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
  * RETURN:      None
  *
  * DESCRIPTION: Converts all versions of the FADT to a common internal format.
- *              -> Expand all 32-bit addresses to 64-bit.
+ *              Expand all 32-bit addresses to 64-bit.
  *
  * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt),
  *              and must contain a copy of the actual FADT.
@@ -292,8 +297,23 @@ static void acpi_tb_convert_fadt(void)
        }
 
        /*
-        * Expand the 32-bit V1.0 addresses to the 64-bit "X" generic address
-        * structures as necessary.
+        * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which
+        * should be zero are indeed zero. This will workaround BIOSs that
+        * inadvertently place values in these fields.
+        *
+        * 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.
+        */
+       if (acpi_gbl_FADT.header.revision < 3) {
+               acpi_gbl_FADT.preferred_profile = 0;
+               acpi_gbl_FADT.pstate_control = 0;
+               acpi_gbl_FADT.cst_control = 0;
+               acpi_gbl_FADT.boot_flags = 0;
+       }
+
+       /*
+        * Expand the ACPI 1.0 32-bit V1.0 addresses to the ACPI 2.0 64-bit "X"
+        * generic address structures as necessary.
         */
        for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
                target =
@@ -334,7 +354,8 @@ static void acpi_tb_convert_fadt(void)
                                     (acpi_gbl_FADT.xpm1a_event_block.address +
                                      pm1_register_length));
        /* Don't forget to copy space_id of the GAS */
-       acpi_gbl_xpm1a_enable.space_id = acpi_gbl_FADT.xpm1a_event_block.space_id;
+       acpi_gbl_xpm1a_enable.space_id =
+           acpi_gbl_FADT.xpm1a_event_block.space_id;
 
        /* The PM1B register block is optional, ignore if not present */
 
@@ -344,20 +365,9 @@ static void acpi_tb_convert_fadt(void)
                                             (acpi_gbl_FADT.xpm1b_event_block.
                                              address + pm1_register_length));
                /* Don't forget to copy space_id of the GAS */
-               acpi_gbl_xpm1b_enable.space_id = acpi_gbl_FADT.xpm1a_event_block.space_id;
-
-       }
+               acpi_gbl_xpm1b_enable.space_id =
+                   acpi_gbl_FADT.xpm1a_event_block.space_id;
 
-       /*
-        * For ACPI 1.0 FADTs, ensure that reserved fields (which should be zero)
-        * are indeed zero. This will workaround BIOSs that inadvertently placed
-        * values in these fields.
-        */
-       if (acpi_gbl_FADT.header.revision < 3) {
-               acpi_gbl_FADT.preferred_profile = 0;
-               acpi_gbl_FADT.pstate_control = 0;
-               acpi_gbl_FADT.cst_control = 0;
-               acpi_gbl_FADT.boot_flags = 0;
        }
 }