1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/cpufreq/e_powersaver.c b/drivers/cpufreq/e_powersaver.c
index 2882d40a3084..4bd6815d317b 100644
--- a/drivers/cpufreq/e_powersaver.c
+++ b/drivers/cpufreq/e_powersaver.c
@@ -43,6 +43,7 @@ static struct eps_cpu_data *eps_cpu[NR_CPUS];
 /* Module parameters */
 static int freq_failsafe_off;
 static int voltage_failsafe_off;
+static int set_max_voltage;
 
 #if defined CONFIG_ACPI_PROCESSOR || defined CONFIG_ACPI_PROCESSOR_MODULE
 static int ignore_acpi_limit;
@@ -340,6 +341,21 @@ static int eps_cpu_init(struct cpufreq_policy *policy)
         }
 #endif
 
+        /* Allow user to set lower maximum voltage then that reported
+         * by processor */
+        if (brand == EPS_BRAND_C7M && set_max_voltage) {
+                u32 v;
+
+                /* Change mV to something hardware can use */
+                v = (set_max_voltage - 700) / 16;
+                /* Check if voltage is within limits */
+                if (v >= min_voltage && v <= max_voltage) {
+                        printk(KERN_INFO "eps: Setting %dmV as maximum.\n",
+                                v * 16 + 700);
+                        max_voltage = v;
+                }
+        }
+
         /* Calc number of p-states supported */
         if (brand == EPS_BRAND_C7M)
                 states = max_multiplier - min_multiplier + 1;
@@ -453,6 +469,8 @@ MODULE_PARM_DESC(voltage_failsafe_off, "Disable current vs max voltage check");
 module_param(ignore_acpi_limit, int, 0644);
 MODULE_PARM_DESC(ignore_acpi_limit, "Don't check ACPI's processor speed limit");
 #endif
+module_param(set_max_voltage, int, 0644);
+MODULE_PARM_DESC(set_max_voltage, "Set maximum CPU voltage (mV) C7-M only");
 
 MODULE_AUTHOR("Rafal Bilski <rafalbilski@interia.pl>");
 MODULE_DESCRIPTION("Enhanced PowerSaver driver for VIA C7 CPU's.");