diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-15 18:17:01 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-15 18:17:01 +0300 |
commit | 1a5d9dbbaf3af4d029a081bd58dc83b6a25d109e (patch) | |
tree | 25988ffefb12daf18931b65bc60b02eb8306d567 /drivers | |
parent | 884e0d3dd59dde1c1f0fbb5b9db2bcdc581982c7 (diff) | |
parent | f3db6de55e95eee6457a14912dd382a6cfc98edd (diff) | |
download | linux-1a5d9dbbaf3af4d029a081bd58dc83b6a25d109e.tar.xz |
Merge tag 'pm-5.9-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull one more power management update from Rafael Wysocki:
"Modify the intel_pstate driver to allow it to work in the passive mode
with hardware-managed P-states (HWP) enabled"
* tag 'pm-5.9-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: intel_pstate: Implement passive mode with HWP enabled
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/cpufreq/cpufreq.c | 6 | ||||
-rw-r--r-- | drivers/cpufreq/intel_pstate.c | 245 |
2 files changed, 184 insertions, 67 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index afad06b91c77..02ab56b2a0d8 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -73,8 +73,6 @@ static inline bool has_target(void) static unsigned int __cpufreq_get(struct cpufreq_policy *policy); static int cpufreq_init_governor(struct cpufreq_policy *policy); static void cpufreq_exit_governor(struct cpufreq_policy *policy); -static int cpufreq_start_governor(struct cpufreq_policy *policy); -static void cpufreq_stop_governor(struct cpufreq_policy *policy); static void cpufreq_governor_limits(struct cpufreq_policy *policy); static int cpufreq_set_policy(struct cpufreq_policy *policy, struct cpufreq_governor *new_gov, @@ -2266,7 +2264,7 @@ static void cpufreq_exit_governor(struct cpufreq_policy *policy) module_put(policy->governor->owner); } -static int cpufreq_start_governor(struct cpufreq_policy *policy) +int cpufreq_start_governor(struct cpufreq_policy *policy) { int ret; @@ -2293,7 +2291,7 @@ static int cpufreq_start_governor(struct cpufreq_policy *policy) return 0; } -static void cpufreq_stop_governor(struct cpufreq_policy *policy) +void cpufreq_stop_governor(struct cpufreq_policy *policy) { if (cpufreq_suspended || !policy->governor) return; diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index fc459c9c00ff..e0220a6fbc69 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -36,6 +36,7 @@ #define INTEL_PSTATE_SAMPLING_INTERVAL (10 * NSEC_PER_MSEC) #define INTEL_CPUFREQ_TRANSITION_LATENCY 20000 +#define INTEL_CPUFREQ_TRANSITION_DELAY_HWP 5000 #define INTEL_CPUFREQ_TRANSITION_DELAY 500 #ifdef CONFIG_ACPI @@ -220,6 +221,7 @@ struct global_params { * preference/bias * @epp_saved: Saved EPP/EPB during system suspend or CPU offline * operation + * @epp_cached Cached HWP energy-performance preference value * @hwp_req_cached: Cached value of the last HWP Request MSR * @hwp_cap_cached: Cached value of the last HWP Capabilities MSR * @last_io_update: Last time when IO wake flag was set @@ -257,6 +259,7 @@ struct cpudata { s16 epp_policy; s16 epp_default; s16 epp_saved; + s16 epp_cached; u64 hwp_req_cached; u64 hwp_cap_cached; u64 last_io_update; @@ -639,6 +642,26 @@ static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data, int *raw return index; } +static int intel_pstate_set_epp(struct cpudata *cpu, u32 epp) +{ + /* + * Use the cached HWP Request MSR value, because in the active mode the + * register itself may be updated by intel_pstate_hwp_boost_up() or + * intel_pstate_hwp_boost_down() at any time. + */ + u64 value = READ_ONCE(cpu->hwp_req_cached); + + value &= ~GENMASK_ULL(31, 24); + value |= (u64)epp << 24; + /* + * The only other updater of hwp_req_cached in the active mode, + * intel_pstate_hwp_set(), is called under the same lock as this + * function, so it cannot run in parallel with the update below. + */ + WRITE_ONCE(cpu->hwp_req_cached, value); + return wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value); +} + static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data, int pref_index, bool use_raw, u32 raw_epp) @@ -650,28 +673,12 @@ static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data, epp = cpu_data->epp_default; if (boot_cpu_has(X86_FEATURE_HWP_EPP)) { - /* - * Use the cached HWP Request MSR value, because the register - * itself may be updated by intel_pstate_hwp_boost_up() or - * intel_pstate_hwp_boost_down() at any time. - */ - u64 value = READ_ONCE(cpu_data->hwp_req_cached); - - value &= ~GENMASK_ULL(31, 24); - if (use_raw) epp = raw_epp; else if (epp == -EINVAL) epp = epp_values[pref_index - 1]; - value |= (u64)epp << 24; - /* - * The only other updater of hwp_req_cached in the active mode, - * intel_pstate_hwp_set(), is called under the same lock as this - * function, so it cannot run in parallel with the update below. - */ - WRITE_ONCE(cpu_data->hwp_req_cached, value); - ret = wrmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, value); + ret = intel_pstate_set_epp(cpu_data, epp); } else { if (epp == -EINVAL) epp = (pref_index - 1) << 2; @@ -697,10 +704,12 @@ static ssize_t show_energy_performance_available_preferences( cpufreq_freq_attr_ro(energy_performance_available_preferences); +static struct cpufreq_driver intel_pstate; + static ssize_t store_energy_performance_preference( struct cpufreq_policy *policy, const char *buf, size_t count) { - struct cpudata *cpu_data = all_cpu_data[policy->cpu]; + struct cpudata *cpu = all_cpu_data[policy->cpu]; char str_preference[21]; bool raw = false; ssize_t ret; @@ -725,15 +734,44 @@ static ssize_t store_energy_performance_preference( raw = true; } + /* + * This function runs with the policy R/W semaphore held, which + * guarantees that the driver pointer will not change while it is + * running. + */ + if (!intel_pstate_driver) + return -EAGAIN; + mutex_lock(&intel_pstate_limits_lock); - ret = intel_pstate_set_energy_pref_index(cpu_data, ret, raw, epp); - if (!ret) - ret = count; + if (intel_pstate_driver == &intel_pstate) { + ret = intel_pstate_set_energy_pref_index(cpu, ret, raw, epp); + } else { + /* + * In the passive mode the governor needs to be stopped on the + * target CPU before the EPP update and restarted after it, + * which is super-heavy-weight, so make sure it is worth doing + * upfront. + */ + if (!raw) + epp = ret ? epp_values[ret - 1] : cpu->epp_default; + + if (cpu->epp_cached != epp) { + int err; + + cpufreq_stop_governor(policy); + ret = intel_pstate_set_epp(cpu, epp); + err = cpufreq_start_governor(policy); + if (!ret) { + cpu->epp_cached = epp; + ret = err; + } + } + } mutex_unlock(&intel_pstate_limits_lock); - return ret; + return ret ?: count; } static ssize_t show_energy_performance_preference( @@ -1145,8 +1183,6 @@ static ssize_t store_no_turbo(struct kobject *a, struct kobj_attribute *b, return count; } -static struct cpufreq_driver intel_pstate; - static void update_qos_request(enum freq_qos_req_type type) { int max_state, turbo_max, freq, i, perf_pct; @@ -1330,9 +1366,10 @@ static const struct attribute_group intel_pstate_attr_group = { static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[]; +static struct kobject *intel_pstate_kobject; + static void __init intel_pstate_sysfs_expose_params(void) { - struct kobject *intel_pstate_kobject; int rc; intel_pstate_kobject = kobject_create_and_add("intel_pstate", @@ -1357,17 +1394,31 @@ static void __init intel_pstate_sysfs_expose_params(void) rc = sysfs_create_file(intel_pstate_kobject, &min_perf_pct.attr); WARN_ON(rc); - if (hwp_active) { - rc = sysfs_create_file(intel_pstate_kobject, - &hwp_dynamic_boost.attr); - WARN_ON(rc); - } - if (x86_match_cpu(intel_pstate_cpu_ee_disable_ids)) { rc = sysfs_create_file(intel_pstate_kobject, &energy_efficiency.attr); WARN_ON(rc); } } + +static void intel_pstate_sysfs_expose_hwp_dynamic_boost(void) +{ + int rc; + + if (!hwp_active) + return; + + rc = sysfs_create_file(intel_pstate_kobject, &hwp_dynamic_boost.attr); + WARN_ON_ONCE(rc); +} + +static void intel_pstate_sysfs_hide_hwp_dynamic_boost(void) +{ + if (!hwp_active) + return; + + sysfs_remove_file(intel_pstate_kobject, &hwp_dynamic_boost.attr); +} + /************************** sysfs end ************************/ static void intel_pstate_hwp_enable(struct cpudata *cpudata) @@ -2247,7 +2298,10 @@ static int intel_pstate_verify_policy(struct cpufreq_policy_data *policy) static void intel_cpufreq_stop_cpu(struct cpufreq_policy *policy) { - intel_pstate_set_min_pstate(all_cpu_data[policy->cpu]); + if (hwp_active) + intel_pstate_hwp_force_min_perf(policy->cpu); + else + intel_pstate_set_min_pstate(all_cpu_data[policy->cpu]); } static void intel_pstate_stop_cpu(struct cpufreq_policy *policy) @@ -2255,12 +2309,10 @@ static void intel_pstate_stop_cpu(struct cpufreq_policy *policy) pr_debug("CPU %d exiting\n", policy->cpu); intel_pstate_clear_update_util_hook(policy->cpu); - if (hwp_active) { + if (hwp_active) intel_pstate_hwp_save_state(policy); - intel_pstate_hwp_force_min_perf(policy->cpu); - } else { - intel_cpufreq_stop_cpu(policy); - } + + intel_cpufreq_stop_cpu(policy); } static int intel_pstate_cpu_exit(struct cpufreq_policy *policy) @@ -2390,13 +2442,71 @@ static void intel_cpufreq_trace(struct cpudata *cpu, unsigned int trace_type, in fp_toint(cpu->iowait_boost * 100)); } +static void intel_cpufreq_adjust_hwp(struct cpudata *cpu, u32 target_pstate, + bool fast_switch) +{ + u64 prev = READ_ONCE(cpu->hwp_req_cached), value = prev; + + value &= ~HWP_MIN_PERF(~0L); + value |= HWP_MIN_PERF(target_pstate); + + /* + * The entire MSR needs to be updated in order to update the HWP min + * field in it, so opportunistically update the max too if needed. + */ + value &= ~HWP_MAX_PERF(~0L); + value |= HWP_MAX_PERF(cpu->max_perf_ratio); + + if (value == prev) + return; + + WRITE_ONCE(cpu->hwp_req_cached, value); + if (fast_switch) + wrmsrl(MSR_HWP_REQUEST, value); + else + wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value); +} + +static void intel_cpufreq_adjust_perf_ctl(struct cpudata *cpu, + u32 target_pstate, bool fast_switch) +{ + if (fast_switch) + wrmsrl(MSR_IA32_PERF_CTL, + pstate_funcs.get_val(cpu, target_pstate)); + else + wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL, + pstate_funcs.get_val(cpu, target_pstate)); +} + +static int intel_cpufreq_update_pstate(struct cpudata *cpu, int target_pstate, + bool fast_switch) +{ + int old_pstate = cpu->pstate.current_pstate; + + target_pstate = intel_pstate_prepare_request(cpu, target_pstate); + if (target_pstate != old_pstate) { + cpu->pstate.current_pstate = target_pstate; + if (hwp_active) + intel_cpufreq_adjust_hwp(cpu, target_pstate, + fast_switch); + else + intel_cpufreq_adjust_perf_ctl(cpu, target_pstate, + fast_switch); + } + + intel_cpufreq_trace(cpu, fast_switch ? INTEL_PSTATE_TRACE_FAST_SWITCH : + INTEL_PSTATE_TRACE_TARGET, old_pstate); + + return target_pstate; +} + static int intel_cpufreq_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { struct cpudata *cpu = all_cpu_data[policy->cpu]; struct cpufreq_freqs freqs; - int target_pstate, old_pstate; + int target_pstate; update_turbo_state(); @@ -2404,6 +2514,7 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy, freqs.new = target_freq; cpufreq_freq_transition_begin(policy, &freqs); + switch (relation) { case CPUFREQ_RELATION_L: target_pstate = DIV_ROUND_UP(freqs.new, cpu->pstate.scaling); @@ -2415,15 +2526,11 @@ static int intel_cpufreq_target(struct cpufreq_policy *policy, target_pstate = DIV_ROUND_CLOSEST(freqs.new, cpu->pstate.scaling); break; } - target_pstate = intel_pstate_prepare_request(cpu, target_pstate); - old_pstate = cpu->pstate.current_pstate; - if (target_pstate != cpu->pstate.current_pstate) { - cpu->pstate.current_pstate = target_pstate; - wrmsrl_on_cpu(policy->cpu, MSR_IA32_PERF_CTL, - pstate_funcs.get_val(cpu, target_pstate)); - } + + target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, false); + freqs.new = target_pstate * cpu->pstate.scaling; - intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_TARGET, old_pstate); + cpufreq_freq_transition_end(policy, &freqs, false); return 0; @@ -2433,15 +2540,14 @@ static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy, unsigned int target_freq) { struct cpudata *cpu = all_cpu_data[policy->cpu]; - int target_pstate, old_pstate; + int target_pstate; update_turbo_state(); target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling); - target_pstate = intel_pstate_prepare_request(cpu, target_pstate); - old_pstate = cpu->pstate.current_pstate; - intel_pstate_update_pstate(cpu, target_pstate); - intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_FAST_SWITCH, old_pstate); + + target_pstate = intel_cpufreq_update_pstate(cpu, target_pstate, true); + return target_pstate * cpu->pstate.scaling; } @@ -2461,7 +2567,6 @@ static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy) return ret; policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY; - policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY; /* This reflects the intel_pstate_get_cpu_pstates() setting. */ policy->cur = policy->cpuinfo.min_freq; @@ -2473,10 +2578,18 @@ static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy) cpu = all_cpu_data[policy->cpu]; - if (hwp_active) + if (hwp_active) { + u64 value; + intel_pstate_get_hwp_max(policy->cpu, &turbo_max, &max_state); - else + policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY_HWP; + rdmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, &value); + WRITE_ONCE(cpu->hwp_req_cached, value); + cpu->epp_cached = (value & GENMASK_ULL(31, 24)) >> 24; + } else { turbo_max = cpu->pstate.turbo_pstate; + policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY; + } min_freq = DIV_ROUND_UP(turbo_max * global.min_perf_pct, 100); min_freq *= cpu->pstate.scaling; @@ -2553,6 +2666,10 @@ static void intel_pstate_driver_cleanup(void) } } put_online_cpus(); + + if (intel_pstate_driver == &intel_pstate) + intel_pstate_sysfs_hide_hwp_dynamic_boost(); + intel_pstate_driver = NULL; } @@ -2560,6 +2677,9 @@ static int intel_pstate_register_driver(struct cpufreq_driver *driver) { int ret; + if (driver == &intel_pstate) + intel_pstate_sysfs_expose_hwp_dynamic_boost(); + memset(&global, 0, sizeof(global)); global.max_perf_pct = 100; @@ -2577,9 +2697,6 @@ static int intel_pstate_register_driver(struct cpufreq_driver *driver) static int intel_pstate_unregister_driver(void) { - if (hwp_active) - return -EBUSY; - cpufreq_unregister_driver(intel_pstate_driver); intel_pstate_driver_cleanup(); @@ -2835,7 +2952,10 @@ static int __init intel_pstate_init(void) hwp_active++; hwp_mode_bdw = id->driver_data; intel_pstate.attr = hwp_cpufreq_attrs; - default_driver = &intel_pstate; + intel_cpufreq.attr = hwp_cpufreq_attrs; + if (!default_driver) + default_driver = &intel_pstate; + goto hwp_cpu_matched; } } else { @@ -2906,14 +3026,13 @@ static int __init intel_pstate_setup(char *str) if (!str) return -EINVAL; - if (!strcmp(str, "disable")) { + if (!strcmp(str, "disable")) no_load = 1; - } else if (!strcmp(str, "active")) { + else if (!strcmp(str, "active")) default_driver = &intel_pstate; - } else if (!strcmp(str, "passive")) { + else if (!strcmp(str, "passive")) default_driver = &intel_cpufreq; - no_hwp = 1; - } + if (!strcmp(str, "no_hwp")) { pr_info("HWP disabled\n"); no_hwp = 1; |