msm: acpuclock-krait: Add voltage boost mode

Add support to bump up or down the voltage via sysfs.

 # echo 1 > /sys/module/acpuclock_krait/parameters/boost

enables the boost and

 # echo 0 > /sys/module/acpuclock_krait/parameters/boost

disables the boost. Boost mode is enabled by default for fast and
nominal devices because those devices could be at the boundaries
of the characterization thresholds and exhibit CPU/L1 errors.

Change-Id: If0dd4ed949188debbb55f82f07004b57548164f6
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
diff --git a/arch/arm/mach-msm/acpuclock-krait.h b/arch/arm/mach-msm/acpuclock-krait.h
index 0b304ec..5d29772 100644
--- a/arch/arm/mach-msm/acpuclock-krait.h
+++ b/arch/arm/mach-msm/acpuclock-krait.h
@@ -222,10 +222,12 @@
  * struct pvs_table - CPU performance level table and size.
  * @table: CPU performance level table
  * @size: sizeof(@table)
+ * @boost_uv: Voltage boost amount
  */
 struct pvs_table {
 	struct acpu_level *table;
 	size_t size;
+	int boost_uv;
 };
 
 /**