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 9070f1fe8f17e73adfdbc91cf0981f857e7b2f09..899d68afc3c5e0bde9be08338ec14399e52c7d32 100644 (file)
--- 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 c10d587c16418ae00b801fc6ca5a63997d30e3ab..e1d9c777b213a3f70b90e8a20f9dd5868a425c29 100644 (file)
--- 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 9bd6f050f299ef55b545dac56a890d8f3219bc18..4e5272c313e0ce5be2d4ead501cb3f41bf9a3e07 100644 (file)
--- 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 0e4ab1fe5966e09897d51b85e710f784a990c6d8..1371cc997393a83224beb5ff8809e0a22e968b67 100644 (file)
--- 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;