From d9460fd227ed2ce52941b6a12ad4de05c195f6aa Mon Sep 17 00:00:00 2001 From: Zhang Rui Date: Thu, 17 Jan 2008 15:51:23 +0800 Subject: [PATCH] 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 Signed-off-by: Zhao Yakui Signed-off-by: Thomas Sujith Signed-off-by: Len Brown --- drivers/acpi/processor_core.c | 23 ++++++ drivers/acpi/processor_thermal.c | 134 +++++++++++++++++++++++++++++-- include/acpi/processor.h | 6 +- 3 files changed, 155 insertions(+), 8 deletions(-) diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index e48ee4f8749f..5668c5e8ae19 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -668,6 +668,24 @@ static int __cpuinit acpi_processor_start(struct acpi_device *device) acpi_processor_power_init(pr, device); + pr->cdev = thermal_cooling_device_register("Processor", device, + &processor_cooling_ops); + if (pr->cdev) + printk(KERN_INFO PREFIX + "%s is registered as cooling_device%d\n", + device->dev.bus_id, pr->cdev->id); + else + goto end; + + result = sysfs_create_link(&device->dev.kobj, &pr->cdev->device.kobj, + "thermal_cooling"); + if (result) + return result; + result = sysfs_create_link(&pr->cdev->device.kobj, &device->dev.kobj, + "device"); + if (result) + return result; + if (pr->flags.throttling) { printk(KERN_INFO PREFIX "%s [%s] (supports", acpi_device_name(device), acpi_device_bid(device)); @@ -791,6 +809,11 @@ static int acpi_processor_remove(struct acpi_device *device, int type) acpi_processor_remove_fs(device); + sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); + sysfs_remove_link(&pr->cdev->device.kobj, "device"); + thermal_cooling_device_unregister(pr->cdev); + pr->cdev = NULL; + processors[pr->id] = NULL; kfree(pr); 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 #include #include +#include #include @@ -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) diff --git a/include/acpi/processor.h b/include/acpi/processor.h index 76411b1fc4fd..0787635a11aa 100644 --- a/include/acpi/processor.h +++ b/include/acpi/processor.h @@ -4,7 +4,7 @@ #include #include #include - +#include #include #define ACPI_PROCESSOR_BUSY_METRIC 10 @@ -218,7 +218,7 @@ struct acpi_processor { struct acpi_processor_performance *performance; struct acpi_processor_throttling throttling; struct acpi_processor_limit limit; - + struct thermal_cooling_device *cdev; /* the _PDC objects for this processor, if any */ struct acpi_object_list *pdc; }; @@ -330,7 +330,7 @@ extern struct cpuidle_driver acpi_idle_driver; /* in processor_thermal.c */ int acpi_processor_get_limit_info(struct acpi_processor *pr); extern struct file_operations acpi_processor_limit_fops; - +extern struct thermal_cooling_device_ops processor_cooling_ops; #ifdef CONFIG_CPU_FREQ void acpi_thermal_cpufreq_init(void); void acpi_thermal_cpufreq_exit(void);