aboutsummaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
Diffstat (limited to 'drivers')
-rw-r--r--drivers/cpufreq/e_powersaver.c41
1 files changed, 30 insertions, 11 deletions
diff --git a/drivers/cpufreq/e_powersaver.c b/drivers/cpufreq/e_powersaver.c
index 35a257dd4bb..84661c54a74 100644
--- a/drivers/cpufreq/e_powersaver.c
+++ b/drivers/cpufreq/e_powersaver.c
@@ -32,6 +32,10 @@ struct eps_cpu_data {
static struct eps_cpu_data *eps_cpu[NR_CPUS];
+/* Module parameters */
+static int freq_failsafe_off;
+static int voltage_failsafe_off;
+
static unsigned int eps_get(unsigned int cpu)
{
@@ -244,9 +248,27 @@ static int eps_cpu_init(struct cpufreq_policy *policy)
return -EINVAL;
if (current_voltage > 0x1f || max_voltage > 0x1f)
return -EINVAL;
- if (max_voltage < min_voltage)
+ if (max_voltage < min_voltage
+ || current_voltage < min_voltage
+ || current_voltage > max_voltage)
return -EINVAL;
+ /* Check for systems using underclocked CPU */
+ if (!freq_failsafe_off && max_multiplier != current_multiplier) {
+ printk(KERN_INFO "eps: Your processor is running at different "
+ "frequency then its maximum. Aborting.\n");
+ printk(KERN_INFO "eps: You can use freq_failsafe_off option "
+ "to disable this check.\n");
+ return -EINVAL;
+ }
+ if (!voltage_failsafe_off && max_voltage != current_voltage) {
+ printk(KERN_INFO "eps: Your processor is running at different "
+ "voltage then its maximum. Aborting.\n");
+ printk(KERN_INFO "eps: You can use voltage_failsafe_off "
+ "option to disable this check.\n");
+ return -EINVAL;
+ }
+
/* Calc FSB speed */
fsb = cpu_khz / current_multiplier;
/* Calc number of p-states supported */
@@ -303,17 +325,7 @@ static int eps_cpu_init(struct cpufreq_policy *policy)
static int eps_cpu_exit(struct cpufreq_policy *policy)
{
unsigned int cpu = policy->cpu;
- struct eps_cpu_data *centaur;
- u32 lo, hi;
-
- if (eps_cpu[cpu] == NULL)
- return -ENODEV;
- centaur = eps_cpu[cpu];
- /* Get max frequency */
- rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
- /* Set max frequency */
- eps_set_state(centaur, cpu, hi & 0xffff);
/* Bye */
cpufreq_frequency_table_put_attr(policy->cpu);
kfree(eps_cpu[cpu]);
@@ -359,6 +371,13 @@ static void __exit eps_exit(void)
cpufreq_unregister_driver(&eps_driver);
}
+/* Allow user to overclock his machine or to change frequency to higher after
+ * unloading module */
+module_param(freq_failsafe_off, int, 0644);
+MODULE_PARM_DESC(freq_failsafe_off, "Disable current vs max frequency check");
+module_param(voltage_failsafe_off, int, 0644);
+MODULE_PARM_DESC(voltage_failsafe_off, "Disable current vs max voltage check");
+
MODULE_AUTHOR("Rafal Bilski <rafalbilski@interia.pl>");
MODULE_DESCRIPTION("Enhanced PowerSaver driver for VIA C7 CPU's.");
MODULE_LICENSE("GPL");