[PATCH] x86: Add acpi_user_timer_override option for Asus boards

Timer overrides are normally disabled on Nvidia board because
they are commonly wrong, except on new ones with HPET support.
Unfortunately there are quite some Asus boards around that
don't have HPET, but need a timer override.

We don't know yet how to handle this transparently,
but at least add a command line option to force the timer override
and let them boot.

Cc: len.brown@intel.com

Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index dd00fd556a60..67473849f20e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -164,6 +164,10 @@ and is between 256 and 4096 characters. It is defined in the file
         acpi_skip_timer_override [HW,ACPI]
                         Recognize and ignore IRQ0/pin2 Interrupt Override.
                         For broken nForce2 BIOS resulting in XT-PIC timer.
+        acpi_use_timer_override [HW,ACPI}
+                        Use timer override. For some broken Nvidia NF5 boards
+                        that require a timer override, but don't have
+                        HPET
 
         acpi_dbg_layer= [HW,ACPI]
                         Format: <int>