ACPI: Add acpi_force_32bit_fadt_addr option to force 32 bit FADT addresses

Some HP laptops seem to have invalid 64 bit FADT X_PM* addresses
which are causing various boot issues.  In these cases, it would
be useful to force ACPI to use the valid legacy 32 bit equivalent
PM addresses.  Add a acpi_force_32bit_fadt_addr to set the ACPICA
acpi_gbl_use32_bit_fadt_addresses to TRUE to force this override.

Link: https://bugs.launchpad.net/bugs/1529381
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 9a53c929f017..64b5431904c3 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -193,6 +193,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         (e.g. thinkpad_acpi, sony_acpi, etc.) instead
                         of the ACPI video.ko driver.
 
+        acpi_force_32bit_fadt_addr
+                        force FADT to use 32 bit addresses rather than the
+                        64 bit X_* addresses. Some firmware have broken 64
+                        bit addresses for force ACPI ignore these and use
+                        the older legacy 32 bit addresses.
+
         acpica_no_return_repair [HW, ACPI]
                         Disable AML predefined validation mechanism
                         This mechanism can repair the evaluation result to make