Messages in this thread Patch in this message | | | From | Perry Yuan <> | Subject | [PATCH v8 09/13] cpufreq: amd-pstate: add driver working mode switch support | Date | Mon, 19 Dec 2022 14:40:38 +0800 |
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From: Perry Yuan <Perry.Yuan@amd.com>
While amd-pstate driver was loaded with specific driver mode, it will need to check which mode is enabled for the pstate driver,add this sysfs entry to show the current status
$ cat /sys/devices/system/cpu/amd-pstate/status active
Meanwhile, user can switch the pstate driver mode with writing mode string to sysfs entry as below.
Enable passive mode: $ sudo bash -c "echo passive > /sys/devices/system/cpu/amd-pstate/status"
Enable active mode (EPP driver mode): $ sudo bash -c "echo active > /sys/devices/system/cpu/amd-pstate/status"
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> --- drivers/cpufreq/amd-pstate.c | 128 +++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+)
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index fc12d35bc7bd..e8996e937e63 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -64,6 +64,7 @@ static struct cpufreq_driver amd_pstate_driver; static struct cpufreq_driver amd_pstate_epp_driver; static struct amd_cpudata **all_cpu_data; static int cppc_state = AMD_PSTATE_DISABLE; +struct kobject *amd_pstate_kobj; static inline int get_mode_idx_from_str(const char *str, size_t size) { @@ -90,6 +91,8 @@ static struct amd_pstate_params global_params; static DEFINE_MUTEX(amd_pstate_limits_lock); static DEFINE_MUTEX(amd_pstate_driver_lock); +static DEFINE_SPINLOCK(cppc_notify_lock); + static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached) { u64 epp; @@ -644,6 +647,8 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy) policy->driver_data = cpudata; amd_pstate_boost_init(cpudata); + if (!default_pstate_driver->adjust_perf) + default_pstate_driver->adjust_perf = amd_pstate_adjust_perf; return 0; @@ -784,12 +789,106 @@ static ssize_t show_energy_performance_preference( return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]); } +static ssize_t amd_pstate_show_status(char *buf) +{ + if (!default_pstate_driver) + return sysfs_emit(buf, "off\n"); + + return sysfs_emit(buf, "%s\n", default_pstate_driver == &amd_pstate_epp_driver ? + "active" : "passive"); +} + +static void amd_pstate_driver_cleanup(void) +{ + unsigned int cpu; + + cpus_read_lock(); + for_each_online_cpu(cpu) { + if (all_cpu_data[cpu]) { + spin_lock(&cppc_notify_lock); + kfree(all_cpu_data[cpu]); + WRITE_ONCE(all_cpu_data[cpu], NULL); + spin_unlock(&cppc_notify_lock); + } + } + cpus_read_unlock(); + + default_pstate_driver = NULL; +} + +static int amd_pstate_update_status(const char *buf, size_t size) +{ + if (size == 3 && !strncmp(buf, "off", size)) { + if (!default_pstate_driver) + return -EINVAL; + + if (cppc_state == AMD_PSTATE_ACTIVE) + return -EBUSY; + + cpufreq_unregister_driver(default_pstate_driver); + amd_pstate_driver_cleanup(); + return 0; + } + + if (size == 6 && !strncmp(buf, "active", size)) { + if (default_pstate_driver) { + if (default_pstate_driver == &amd_pstate_epp_driver) + return 0; + cpufreq_unregister_driver(default_pstate_driver); + default_pstate_driver = &amd_pstate_epp_driver; + cppc_state = AMD_PSTATE_ACTIVE; + } + + return cpufreq_register_driver(default_pstate_driver); + } + + if (size == 7 && !strncmp(buf, "passive", size)) { + if (default_pstate_driver) { + if (default_pstate_driver == &amd_pstate_driver) + return 0; + cpufreq_unregister_driver(default_pstate_driver); + cppc_state = AMD_PSTATE_PASSIVE; + default_pstate_driver = &amd_pstate_driver; + } + + return cpufreq_register_driver(default_pstate_driver); + } + + return -EINVAL; +} + +static ssize_t show_status(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + ssize_t ret; + + mutex_lock(&amd_pstate_driver_lock); + ret = amd_pstate_show_status(buf); + mutex_unlock(&amd_pstate_driver_lock); + + return ret; +} + +static ssize_t store_status(struct kobject *a, struct kobj_attribute *b, + const char *buf, size_t count) +{ + char *p = memchr(buf, '\n', count); + int ret; + + mutex_lock(&amd_pstate_driver_lock); + ret = amd_pstate_update_status(buf, p ? p - buf : count); + mutex_unlock(&amd_pstate_driver_lock); + + return ret < 0 ? ret : count; +} + cpufreq_freq_attr_ro(amd_pstate_max_freq); cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); cpufreq_freq_attr_ro(amd_pstate_highest_perf); cpufreq_freq_attr_rw(energy_performance_preference); cpufreq_freq_attr_ro(energy_performance_available_preferences); +define_one_global_rw(status); static struct freq_attr *amd_pstate_attr[] = { &amd_pstate_max_freq, @@ -807,6 +906,15 @@ static struct freq_attr *amd_pstate_epp_attr[] = { NULL, }; +static struct attribute *pstate_global_attributes[] = { + &status.attr, + NULL +}; + +static const struct attribute_group amd_pstate_global_attr_group = { + .attrs = pstate_global_attributes, +}; + static inline void update_boost_state(void) { u64 misc_en; @@ -1228,6 +1336,26 @@ static int __init amd_pstate_init(void) if (ret) pr_err("failed to register with return %d\n", ret); + amd_pstate_kobj = kobject_create_and_add("amd-pstate", &cpu_subsys.dev_root->kobj); + if (!amd_pstate_kobj) { + ret = -EINVAL; + pr_err("global sysfs registration failed.\n"); + goto kobject_free; + } + + ret = sysfs_create_group(amd_pstate_kobj, &amd_pstate_global_attr_group); + if (ret) { + pr_err("sysfs attribute export failed with error %d.\n", ret); + goto global_attr_free; + } + + return ret; + +global_attr_free: + kobject_put(amd_pstate_kobj); +kobject_free: + kfree(cpudata); + cpufreq_unregister_driver(default_pstate_driver); return ret; } device_initcall(amd_pstate_init); -- 2.34.1
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