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author | Zhang Rui <rui.zhang@intel.com> | 2008-01-17 15:51:23 +0800 |
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committer | Len Brown <len.brown@intel.com> | 2008-02-01 23:18:19 -0500 |
commit | d9460fd227ed2ce52941b6a12ad4de05c195f6aa (patch) | |
tree | 1fb877cf41c8599e0fc9c1fbf902b88baba60708 /drivers/acpi/processor_thermal.c | |
parent | 05a83d972293f39a66bc2aa409a5e7996bba585d (diff) | |
download | linux-d9460fd227ed2ce52941b6a12ad4de05c195f6aa.tar.gz linux-d9460fd227ed2ce52941b6a12ad4de05c195f6aa.tar.bz2 linux-d9460fd227ed2ce52941b6a12ad4de05c195f6aa.zip |
ACPI: register ACPI Processor as generic thermal cooling device
Register ACPI processor as thermal cooling devices.
A combination of processor T-state and P-state are used for thermal throttling.
the processor will reduce the frequency first and then set the T-state.
we use cpufreq_thermal_reduction_pctg to calculate the cpufreq limit,
and call cpufreq_verify_with_limit to set the cpufreq limit.
if cpufreq driver is loaded, then we have four cooling state for cpufreq control.
cooling state 0: cpufreq limit == max_freq
cooling state 1: cpufreq limit == max_freq * 80%
cooling state 2: cpufreq limit == max_freq * 60%
cooling state 3: cpufreq limit == max_freq * 40%
after the cpufreq limit is set to 40 percentage of the max_freq,
we use T-state for cooling.
eg. a processor has P-state support, and it has 8 T-state (T0-T7),
the max_state of the proceesor is 10:
state cpufreq-limit T-state
0: max_freq T0
1: max_freq * 80% T0
2: max_freq * 60% T0
3: max_freq * 40% T0
4: max_freq * 40% T1
5: max_freq * 40% T2
6: max_freq * 40% T3
7: max_freq * 40% T4
8: max_freq * 40% T5
9: max_freq * 40% T6
10: max_freq * 40% T7
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Thomas Sujith <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/processor_thermal.c')
-rw-r--r-- | drivers/acpi/processor_thermal.c | 134 |
1 files changed, 129 insertions, 5 deletions
diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c index 06e6f3fb8825..9cb43f52f7b6 100644 --- a/drivers/acpi/processor_thermal.c +++ b/drivers/acpi/processor_thermal.c @@ -32,6 +32,7 @@ #include <linux/cpufreq.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> +#include <linux/sysdev.h> #include <asm/uaccess.h> @@ -93,6 +94,9 @@ static int acpi_processor_apply_limit(struct acpi_processor *pr) * _any_ cpufreq driver and not only the acpi-cpufreq driver. */ +#define CPUFREQ_THERMAL_MIN_STEP 0 +#define CPUFREQ_THERMAL_MAX_STEP 3 + static unsigned int cpufreq_thermal_reduction_pctg[NR_CPUS]; static unsigned int acpi_thermal_cpufreq_is_init = 0; @@ -109,8 +113,9 @@ static int acpi_thermal_cpufreq_increase(unsigned int cpu) if (!cpu_has_cpufreq(cpu)) return -ENODEV; - if (cpufreq_thermal_reduction_pctg[cpu] < 60) { - cpufreq_thermal_reduction_pctg[cpu] += 20; + if (cpufreq_thermal_reduction_pctg[cpu] < + CPUFREQ_THERMAL_MAX_STEP) { + cpufreq_thermal_reduction_pctg[cpu]++; cpufreq_update_policy(cpu); return 0; } @@ -123,8 +128,9 @@ static int acpi_thermal_cpufreq_decrease(unsigned int cpu) if (!cpu_has_cpufreq(cpu)) return -ENODEV; - if (cpufreq_thermal_reduction_pctg[cpu] > 20) - cpufreq_thermal_reduction_pctg[cpu] -= 20; + if (cpufreq_thermal_reduction_pctg[cpu] > + (CPUFREQ_THERMAL_MIN_STEP + 1)) + cpufreq_thermal_reduction_pctg[cpu]--; else cpufreq_thermal_reduction_pctg[cpu] = 0; cpufreq_update_policy(cpu); @@ -143,7 +149,7 @@ static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb, max_freq = (policy->cpuinfo.max_freq * - (100 - cpufreq_thermal_reduction_pctg[policy->cpu])) / 100; + (100 - cpufreq_thermal_reduction_pctg[policy->cpu] * 20)) / 100; cpufreq_verify_within_limits(policy, 0, max_freq); @@ -155,6 +161,32 @@ static struct notifier_block acpi_thermal_cpufreq_notifier_block = { .notifier_call = acpi_thermal_cpufreq_notifier, }; +static int cpufreq_get_max_state(unsigned int cpu) +{ + if (!cpu_has_cpufreq(cpu)) + return 0; + + return CPUFREQ_THERMAL_MAX_STEP; +} + +static int cpufreq_get_cur_state(unsigned int cpu) +{ + if (!cpu_has_cpufreq(cpu)) + return 0; + + return cpufreq_thermal_reduction_pctg[cpu]; +} + +static int cpufreq_set_cur_state(unsigned int cpu, int state) +{ + if (!cpu_has_cpufreq(cpu)) + return 0; + + cpufreq_thermal_reduction_pctg[cpu] = state; + cpufreq_update_policy(cpu); + return 0; +} + void acpi_thermal_cpufreq_init(void) { int i; @@ -179,6 +211,20 @@ void acpi_thermal_cpufreq_exit(void) } #else /* ! CONFIG_CPU_FREQ */ +static int cpufreq_get_max_state(unsigned int cpu) +{ + return 0; +} + +static int cpufreq_get_cur_state(unsigned int cpu) +{ + return 0; +} + +static int cpufreq_set_cur_state(unsigned int cpu, int state) +{ + return 0; +} static int acpi_thermal_cpufreq_increase(unsigned int cpu) { @@ -310,6 +356,84 @@ int acpi_processor_get_limit_info(struct acpi_processor *pr) return 0; } +/* thermal coolign device callbacks */ +static int acpi_processor_max_state(struct acpi_processor *pr) +{ + int max_state = 0; + + /* + * There exists four states according to + * cpufreq_thermal_reduction_ptg. 0, 1, 2, 3 + */ + max_state += cpufreq_get_max_state(pr->id); + if (pr->flags.throttling) + max_state += (pr->throttling.state_count -1); + + return max_state; +} +static int +processor_get_max_state(struct thermal_cooling_device *cdev, char *buf) +{ + struct acpi_device *device = cdev->devdata; + struct acpi_processor *pr = acpi_driver_data(device); + + if (!device || !pr) + return -EINVAL; + + return sprintf(buf, "%d\n", acpi_processor_max_state(pr)); +} + +static int +processor_get_cur_state(struct thermal_cooling_device *cdev, char *buf) +{ + struct acpi_device *device = cdev->devdata; + struct acpi_processor *pr = acpi_driver_data(device); + int cur_state; + + if (!device || !pr) + return -EINVAL; + + cur_state = cpufreq_get_cur_state(pr->id); + if (pr->flags.throttling) + cur_state += pr->throttling.state; + + return sprintf(buf, "%d\n", cur_state); +} + +static int +processor_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state) +{ + struct acpi_device *device = cdev->devdata; + struct acpi_processor *pr = acpi_driver_data(device); + int result = 0; + int max_pstate; + + if (!device || !pr) + return -EINVAL; + + max_pstate = cpufreq_get_max_state(pr->id); + + if (state > acpi_processor_max_state(pr)) + return -EINVAL; + + if (state <= max_pstate) { + if (pr->flags.throttling && pr->throttling.state) + result = acpi_processor_set_throttling(pr, 0); + cpufreq_set_cur_state(pr->id, state); + } else { + cpufreq_set_cur_state(pr->id, max_pstate); + result = acpi_processor_set_throttling(pr, + state - max_pstate); + } + return result; +} + +struct thermal_cooling_device_ops processor_cooling_ops = { + .get_max_state = processor_get_max_state, + .get_cur_state = processor_get_cur_state, + .set_cur_state = processor_set_cur_state, +}; + /* /proc interface */ static int acpi_processor_limit_seq_show(struct seq_file *seq, void *offset) |