diff options
| -rw-r--r-- | drivers/acpi/tables/tbfadt.c | 44 |
1 files changed, 26 insertions, 18 deletions
diff --git a/drivers/acpi/tables/tbfadt.c b/drivers/acpi/tables/tbfadt.c index 1285e91474fb..002bb33003af 100644 --- 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 = @@ -349,18 +369,6 @@ static void acpi_tb_convert_fadt(void) 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; - } } /****************************************************************************** |