diff options
Diffstat (limited to 'drivers/acpi/processor_thermal.c')
| -rw-r--r-- | drivers/acpi/processor_thermal.c | 49 |
1 files changed, 40 insertions, 9 deletions
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c index b7c6287eccca..1219adb11ab9 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) |