ACPICA: Truncate I/O addresses to 16 bits for Windows compatibility
This feature is optional and is enabled if the BIOS requests any
Windows OSI strings. It can also be enabled by the host OS.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
index 9070f1f..899d68a 100644
--- a/drivers/acpi/acpica/acglobal.h
+++ b/drivers/acpi/acpica/acglobal.h
@@ -125,6 +125,14 @@
*/
u8 ACPI_INIT_GLOBAL(acpi_gbl_copy_dsdt_locally, FALSE);
+/*
+ * Optionally truncate I/O addresses to 16 bits. Provides compatibility
+ * with other ACPI implementations. NOTE: During ACPICA initialization,
+ * this value is set to TRUE if any Windows OSI strings have been
+ * requested by the BIOS.
+ */
+u8 ACPI_INIT_GLOBAL(acpi_gbl_truncate_io_addresses, FALSE);
+
/* acpi_gbl_FADT is a local copy of the FADT, converted to a common format. */
struct acpi_table_fadt acpi_gbl_FADT;
diff --git a/drivers/acpi/acpica/hwvalid.c b/drivers/acpi/acpica/hwvalid.c
index c10d587..e1d9c77 100644
--- a/drivers/acpi/acpica/hwvalid.c
+++ b/drivers/acpi/acpica/hwvalid.c
@@ -222,6 +222,12 @@
u32 one_byte;
u32 i;
+ /* Truncate address to 16 bits if requested */
+
+ if (acpi_gbl_truncate_io_addresses) {
+ address &= ACPI_UINT16_MAX;
+ }
+
/* Validate the entire request and perform the I/O */
status = acpi_hw_validate_io_request(address, width);
@@ -279,6 +285,12 @@
acpi_status status;
u32 i;
+ /* Truncate address to 16 bits if requested */
+
+ if (acpi_gbl_truncate_io_addresses) {
+ address &= ACPI_UINT16_MAX;
+ }
+
/* Validate the entire request and perform the I/O */
status = acpi_hw_validate_io_request(address, width);
diff --git a/drivers/acpi/acpica/nsinit.c b/drivers/acpi/acpica/nsinit.c
index 9bd6f05..4e5272c 100644
--- a/drivers/acpi/acpica/nsinit.c
+++ b/drivers/acpi/acpica/nsinit.c
@@ -193,6 +193,15 @@
acpi_ns_init_one_device, NULL, &info,
NULL);
+ /*
+ * Any _OSI requests should be completed by now. If the BIOS has
+ * requested any Windows OSI strings, we will always truncate
+ * I/O addresses to 16 bits -- for Windows compatibility.
+ */
+ if (acpi_gbl_osi_data >= ACPI_OSI_WIN_2000) {
+ acpi_gbl_truncate_io_addresses = TRUE;
+ }
+
ACPI_FREE(info.evaluate_info);
if (ACPI_FAILURE(status)) {
goto error_exit;