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authorMatthew Garrett <mjg@redhat.com>2010-05-26 07:50:48 +0400
committerLen Brown <len.brown@intel.com>2010-06-12 08:55:50 +0400
commitb681f7d9ab4d697a214fa4428795790c3a937a89 (patch)
treec5653b6da518198ca3d7fd13f5f8442428955e1f
parent9cbfa18e8a7b34a32eddbd914a07f085962f50a8 (diff)
downloadlinux-b681f7d9ab4d697a214fa4428795790c3a937a89.tar.xz
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>
-rw-r--r--drivers/acpi/acpica/acglobal.h8
-rw-r--r--drivers/acpi/acpica/hwvalid.c12
-rw-r--r--drivers/acpi/acpica/nsinit.c9
-rw-r--r--include/acpi/acpixf.h1
4 files changed, 30 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
index 9070f1fe8f17..899d68afc3c5 100644
--- a/drivers/acpi/acpica/acglobal.h
+++ b/drivers/acpi/acpica/acglobal.h
@@ -125,6 +125,14 @@ u8 ACPI_INIT_GLOBAL(acpi_gbl_enable_aml_debug_object, FALSE);
*/
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 c10d587c1641..e1d9c777b213 100644
--- a/drivers/acpi/acpica/hwvalid.c
+++ b/drivers/acpi/acpica/hwvalid.c
@@ -222,6 +222,12 @@ acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
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 acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
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 9bd6f050f299..4e5272c313e0 100644
--- a/drivers/acpi/acpica/nsinit.c
+++ b/drivers/acpi/acpica/nsinit.c
@@ -193,6 +193,15 @@ acpi_status acpi_ns_initialize_devices(void)
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;
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index 0e4ab1fe5966..1371cc997393 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -69,6 +69,7 @@ extern acpi_name acpi_gbl_trace_method_name;
extern u32 acpi_gbl_trace_flags;
extern u8 acpi_gbl_enable_aml_debug_object;
extern u8 acpi_gbl_copy_dsdt_locally;
+extern u8 acpi_gbl_truncate_io_addresses;
extern u32 acpi_current_gpe_count;
extern struct acpi_table_fadt acpi_gbl_FADT;