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Diffstat (limited to 'drivers/acpi/processor_thermal.c')
-rw-r--r--drivers/acpi/processor_thermal.c49
1 files changed, 40 insertions, 9 deletions
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index b7c6287ecc..1219adb11a 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c
@@ -17,6 +17,8 @@
#include <acpi/processor.h>
#include <linux/uaccess.h>
+#include "internal.h"
+
#ifdef CONFIG_CPU_FREQ
/* If a passive cooling situation is detected, primarily CPUfreq is used, as it
@@ -26,12 +28,21 @@
*/
#define CPUFREQ_THERMAL_MIN_STEP 0
-#define CPUFREQ_THERMAL_MAX_STEP 3
-static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_pctg);
+static int cpufreq_thermal_max_step __read_mostly = 3;
+
+/*
+ * Minimum throttle percentage for processor_thermal cooling device.
+ * The processor_thermal driver uses it to calculate the percentage amount by
+ * which cpu frequency must be reduced for each cooling state. This is also used
+ * to calculate the maximum number of throttling steps or cooling states.
+ */
+static int cpufreq_thermal_reduction_pctg __read_mostly = 20;
-#define reduction_pctg(cpu) \
- per_cpu(cpufreq_thermal_reduction_pctg, phys_package_first_cpu(cpu))
+static DEFINE_PER_CPU(unsigned int, cpufreq_thermal_reduction_step);
+
+#define reduction_step(cpu) \
+ per_cpu(cpufreq_thermal_reduction_step, phys_package_first_cpu(cpu))
/*
* Emulate "per package data" using per cpu data (which should really be
@@ -71,7 +82,7 @@ static int cpufreq_get_max_state(unsigned int cpu)
if (!cpu_has_cpufreq(cpu))
return 0;
- return CPUFREQ_THERMAL_MAX_STEP;
+ return cpufreq_thermal_max_step;
}
static int cpufreq_get_cur_state(unsigned int cpu)
@@ -79,7 +90,7 @@ static int cpufreq_get_cur_state(unsigned int cpu)
if (!cpu_has_cpufreq(cpu))
return 0;
- return reduction_pctg(cpu);
+ return reduction_step(cpu);
}
static int cpufreq_set_cur_state(unsigned int cpu, int state)
@@ -92,7 +103,7 @@ static int cpufreq_set_cur_state(unsigned int cpu, int state)
if (!cpu_has_cpufreq(cpu))
return 0;
- reduction_pctg(cpu) = state;
+ reduction_step(cpu) = state;
/*
* Update all the CPUs in the same package because they all
@@ -113,7 +124,8 @@ static int cpufreq_set_cur_state(unsigned int cpu, int state)
if (!policy)
return -EINVAL;
- max_freq = (policy->cpuinfo.max_freq * (100 - reduction_pctg(i) * 20)) / 100;
+ max_freq = (policy->cpuinfo.max_freq *
+ (100 - reduction_step(i) * cpufreq_thermal_reduction_pctg)) / 100;
cpufreq_cpu_put(policy);
@@ -126,10 +138,29 @@ static int cpufreq_set_cur_state(unsigned int cpu, int state)
return 0;
}
+static void acpi_thermal_cpufreq_config(void)
+{
+ int cpufreq_pctg = acpi_arch_thermal_cpufreq_pctg();
+
+ if (!cpufreq_pctg)
+ return;
+
+ cpufreq_thermal_reduction_pctg = cpufreq_pctg;
+
+ /*
+ * Derive the MAX_STEP from minimum throttle percentage so that the reduction
+ * percentage doesn't end up becoming negative. Also, cap the MAX_STEP so that
+ * the CPU performance doesn't become 0.
+ */
+ cpufreq_thermal_max_step = (100 / cpufreq_pctg) - 2;
+}
+
void acpi_thermal_cpufreq_init(struct cpufreq_policy *policy)
{
unsigned int cpu;
+ acpi_thermal_cpufreq_config();
+
for_each_cpu(cpu, policy->related_cpus) {
struct acpi_processor *pr = per_cpu(processors, cpu);
int ret;
@@ -190,7 +221,7 @@ static int acpi_processor_max_state(struct acpi_processor *pr)
/*
* There exists four states according to
- * cpufreq_thermal_reduction_pctg. 0, 1, 2, 3
+ * cpufreq_thermal_reduction_step. 0, 1, 2, 3
*/
max_state += cpufreq_get_max_state(pr->id);
if (pr->flags.throttling)