Merge tag 'pm-turbostat-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-microblaze.git] / drivers / cpufreq / intel_pstate.c
index 50bd6d9..108826d 100644 (file)
 
 #define INTEL_CPUFREQ_TRANSITION_LATENCY       20000
 
-#define ATOM_RATIOS            0x66a
-#define ATOM_VIDS              0x66b
-#define ATOM_TURBO_RATIOS      0x66c
-#define ATOM_TURBO_VIDS                0x66d
-
 #ifdef CONFIG_ACPI
 #include <acpi/processor.h>
 #include <acpi/cppc_acpi.h>
@@ -358,42 +353,33 @@ static struct pstate_funcs pstate_funcs __read_mostly;
 static int hwp_active __read_mostly;
 static bool per_cpu_limits __read_mostly;
 
+static bool driver_registered __read_mostly;
+
 #ifdef CONFIG_ACPI
 static bool acpi_ppc;
 #endif
 
-static struct perf_limits performance_limits = {
-       .no_turbo = 0,
-       .turbo_disabled = 0,
-       .max_perf_pct = 100,
-       .max_perf = int_ext_tofp(1),
-       .min_perf_pct = 100,
-       .min_perf = int_ext_tofp(1),
-       .max_policy_pct = 100,
-       .max_sysfs_pct = 100,
-       .min_policy_pct = 0,
-       .min_sysfs_pct = 0,
-};
+static struct perf_limits performance_limits;
+static struct perf_limits powersave_limits;
+static struct perf_limits *limits;
 
-static struct perf_limits powersave_limits = {
-       .no_turbo = 0,
-       .turbo_disabled = 0,
-       .max_perf_pct = 100,
-       .max_perf = int_ext_tofp(1),
-       .min_perf_pct = 0,
-       .min_perf = 0,
-       .max_policy_pct = 100,
-       .max_sysfs_pct = 100,
-       .min_policy_pct = 0,
-       .min_sysfs_pct = 0,
-};
+static void intel_pstate_init_limits(struct perf_limits *limits)
+{
+       memset(limits, 0, sizeof(*limits));
+       limits->max_perf_pct = 100;
+       limits->max_perf = int_ext_tofp(1);
+       limits->max_policy_pct = 100;
+       limits->max_sysfs_pct = 100;
+}
 
-#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
-static struct perf_limits *limits = &performance_limits;
-#else
-static struct perf_limits *limits = &powersave_limits;
-#endif
+static void intel_pstate_set_performance_limits(struct perf_limits *limits)
+{
+       intel_pstate_init_limits(limits);
+       limits->min_perf_pct = 100;
+       limits->min_perf = int_ext_tofp(1);
+}
 
+static DEFINE_MUTEX(intel_pstate_driver_lock);
 static DEFINE_MUTEX(intel_pstate_limits_lock);
 
 #ifdef CONFIG_ACPI
@@ -538,7 +524,6 @@ static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
 
        acpi_processor_unregister_performance(policy->cpu);
 }
-
 #else
 static inline void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
 {
@@ -873,7 +858,10 @@ static void intel_pstate_hwp_set(struct cpufreq_policy *policy)
 
                rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
                hw_min = HWP_LOWEST_PERF(cap);
-               hw_max = HWP_HIGHEST_PERF(cap);
+               if (limits->no_turbo)
+                       hw_max = HWP_GUARANTEED_PERF(cap);
+               else
+                       hw_max = HWP_HIGHEST_PERF(cap);
                range = hw_max - hw_min;
 
                max_perf_pct = perf_limits->max_perf_pct;
@@ -887,11 +875,6 @@ static void intel_pstate_hwp_set(struct cpufreq_policy *policy)
 
                adj_range = max_perf_pct * range / 100;
                max = hw_min + adj_range;
-               if (limits->no_turbo) {
-                       hw_max = HWP_GUARANTEED_PERF(cap);
-                       if (hw_max < max)
-                               max = hw_max;
-               }
 
                value &= ~HWP_MAX_PERF(~0L);
                value |= HWP_MAX_PERF(max);
@@ -1007,37 +990,59 @@ static int pid_param_get(void *data, u64 *val)
 }
 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
 
+static struct dentry *debugfs_parent;
+
 struct pid_param {
        char *name;
        void *value;
+       struct dentry *dentry;
 };
 
 static struct pid_param pid_files[] = {
-       {"sample_rate_ms", &pid_params.sample_rate_ms},
-       {"d_gain_pct", &pid_params.d_gain_pct},
-       {"i_gain_pct", &pid_params.i_gain_pct},
-       {"deadband", &pid_params.deadband},
-       {"setpoint", &pid_params.setpoint},
-       {"p_gain_pct", &pid_params.p_gain_pct},
-       {NULL, NULL}
+       {"sample_rate_ms", &pid_params.sample_rate_ms},
+       {"d_gain_pct", &pid_params.d_gain_pct},
+       {"i_gain_pct", &pid_params.i_gain_pct},
+       {"deadband", &pid_params.deadband},
+       {"setpoint", &pid_params.setpoint},
+       {"p_gain_pct", &pid_params.p_gain_pct},
+       {NULL, NULL}
 };
 
-static void __init intel_pstate_debug_expose_params(void)
+static void intel_pstate_debug_expose_params(void)
 {
-       struct dentry *debugfs_parent;
-       int i = 0;
+       int i;
 
        debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
        if (IS_ERR_OR_NULL(debugfs_parent))
                return;
-       while (pid_files[i].name) {
-               debugfs_create_file(pid_files[i].name, 0660,
-                                   debugfs_parent, pid_files[i].value,
-                                   &fops_pid_param);
-               i++;
+
+       for (i = 0; pid_files[i].name; i++) {
+               struct dentry *dentry;
+
+               dentry = debugfs_create_file(pid_files[i].name, 0660,
+                                            debugfs_parent, pid_files[i].value,
+                                            &fops_pid_param);
+               if (!IS_ERR(dentry))
+                       pid_files[i].dentry = dentry;
        }
 }
 
+static void intel_pstate_debug_hide_params(void)
+{
+       int i;
+
+       if (IS_ERR_OR_NULL(debugfs_parent))
+               return;
+
+       for (i = 0; pid_files[i].name; i++) {
+               debugfs_remove(pid_files[i].dentry);
+               pid_files[i].dentry = NULL;
+       }
+
+       debugfs_remove(debugfs_parent);
+       debugfs_parent = NULL;
+}
+
 /************************** debugfs end ************************/
 
 /************************** sysfs begin ************************/
@@ -1048,6 +1053,34 @@ static void __init intel_pstate_debug_expose_params(void)
                return sprintf(buf, "%u\n", limits->object);            \
        }
 
+static ssize_t intel_pstate_show_status(char *buf);
+static int intel_pstate_update_status(const char *buf, size_t size);
+
+static ssize_t show_status(struct kobject *kobj,
+                          struct attribute *attr, char *buf)
+{
+       ssize_t ret;
+
+       mutex_lock(&intel_pstate_driver_lock);
+       ret = intel_pstate_show_status(buf);
+       mutex_unlock(&intel_pstate_driver_lock);
+
+       return ret;
+}
+
+static ssize_t store_status(struct kobject *a, struct attribute *b,
+                           const char *buf, size_t count)
+{
+       char *p = memchr(buf, '\n', count);
+       int ret;
+
+       mutex_lock(&intel_pstate_driver_lock);
+       ret = intel_pstate_update_status(buf, p ? p - buf : count);
+       mutex_unlock(&intel_pstate_driver_lock);
+
+       return ret < 0 ? ret : count;
+}
+
 static ssize_t show_turbo_pct(struct kobject *kobj,
                                struct attribute *attr, char *buf)
 {
@@ -1055,12 +1088,22 @@ static ssize_t show_turbo_pct(struct kobject *kobj,
        int total, no_turbo, turbo_pct;
        uint32_t turbo_fp;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        cpu = all_cpu_data[0];
 
        total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
        no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
        turbo_fp = div_fp(no_turbo, total);
        turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
+
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return sprintf(buf, "%u\n", turbo_pct);
 }
 
@@ -1070,8 +1113,18 @@ static ssize_t show_num_pstates(struct kobject *kobj,
        struct cpudata *cpu;
        int total;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        cpu = all_cpu_data[0];
        total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
+
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return sprintf(buf, "%u\n", total);
 }
 
@@ -1080,12 +1133,21 @@ static ssize_t show_no_turbo(struct kobject *kobj,
 {
        ssize_t ret;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        update_turbo_state();
        if (limits->turbo_disabled)
                ret = sprintf(buf, "%u\n", limits->turbo_disabled);
        else
                ret = sprintf(buf, "%u\n", limits->no_turbo);
 
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return ret;
 }
 
@@ -1099,12 +1161,20 @@ static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
        if (ret != 1)
                return -EINVAL;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        mutex_lock(&intel_pstate_limits_lock);
 
        update_turbo_state();
        if (limits->turbo_disabled) {
                pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
                mutex_unlock(&intel_pstate_limits_lock);
+               mutex_unlock(&intel_pstate_driver_lock);
                return -EPERM;
        }
 
@@ -1114,6 +1184,8 @@ static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 
        intel_pstate_update_policies();
 
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return count;
 }
 
@@ -1127,6 +1199,13 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
        if (ret != 1)
                return -EINVAL;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        mutex_lock(&intel_pstate_limits_lock);
 
        limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
@@ -1142,6 +1221,8 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 
        intel_pstate_update_policies();
 
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return count;
 }
 
@@ -1155,6 +1236,13 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
        if (ret != 1)
                return -EINVAL;
 
+       mutex_lock(&intel_pstate_driver_lock);
+
+       if (!driver_registered) {
+               mutex_unlock(&intel_pstate_driver_lock);
+               return -EAGAIN;
+       }
+
        mutex_lock(&intel_pstate_limits_lock);
 
        limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
@@ -1170,12 +1258,15 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 
        intel_pstate_update_policies();
 
+       mutex_unlock(&intel_pstate_driver_lock);
+
        return count;
 }
 
 show_one(max_perf_pct, max_perf_pct);
 show_one(min_perf_pct, min_perf_pct);
 
+define_one_global_rw(status);
 define_one_global_rw(no_turbo);
 define_one_global_rw(max_perf_pct);
 define_one_global_rw(min_perf_pct);
@@ -1183,6 +1274,7 @@ define_one_global_ro(turbo_pct);
 define_one_global_ro(num_pstates);
 
 static struct attribute *intel_pstate_attributes[] = {
+       &status.attr,
        &no_turbo.attr,
        &turbo_pct.attr,
        &num_pstates.attr,
@@ -1258,7 +1350,7 @@ static int atom_get_min_pstate(void)
 {
        u64 value;
 
-       rdmsrl(ATOM_RATIOS, value);
+       rdmsrl(MSR_ATOM_CORE_RATIOS, value);
        return (value >> 8) & 0x7F;
 }
 
@@ -1266,7 +1358,7 @@ static int atom_get_max_pstate(void)
 {
        u64 value;
 
-       rdmsrl(ATOM_RATIOS, value);
+       rdmsrl(MSR_ATOM_CORE_RATIOS, value);
        return (value >> 16) & 0x7F;
 }
 
@@ -1274,7 +1366,7 @@ static int atom_get_turbo_pstate(void)
 {
        u64 value;
 
-       rdmsrl(ATOM_TURBO_RATIOS, value);
+       rdmsrl(MSR_ATOM_CORE_TURBO_RATIOS, value);
        return value & 0x7F;
 }
 
@@ -1336,7 +1428,7 @@ static void atom_get_vid(struct cpudata *cpudata)
 {
        u64 value;
 
-       rdmsrl(ATOM_VIDS, value);
+       rdmsrl(MSR_ATOM_CORE_VIDS, value);
        cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
        cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
        cpudata->vid.ratio = div_fp(
@@ -1344,7 +1436,7 @@ static void atom_get_vid(struct cpudata *cpudata)
                int_tofp(cpudata->pstate.max_pstate -
                        cpudata->pstate.min_pstate));
 
-       rdmsrl(ATOM_TURBO_VIDS, value);
+       rdmsrl(MSR_ATOM_CORE_TURBO_VIDS, value);
        cpudata->vid.turbo = value & 0x7f;
 }
 
@@ -1364,48 +1456,71 @@ static int core_get_max_pstate_physical(void)
        return (value >> 8) & 0xFF;
 }
 
+static int core_get_tdp_ratio(u64 plat_info)
+{
+       /* Check how many TDP levels present */
+       if (plat_info & 0x600000000) {
+               u64 tdp_ctrl;
+               u64 tdp_ratio;
+               int tdp_msr;
+               int err;
+
+               /* Get the TDP level (0, 1, 2) to get ratios */
+               err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
+               if (err)
+                       return err;
+
+               /* TDP MSR are continuous starting at 0x648 */
+               tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x03);
+               err = rdmsrl_safe(tdp_msr, &tdp_ratio);
+               if (err)
+                       return err;
+
+               /* For level 1 and 2, bits[23:16] contain the ratio */
+               if (tdp_ctrl & 0x03)
+                       tdp_ratio >>= 16;
+
+               tdp_ratio &= 0xff; /* ratios are only 8 bits long */
+               pr_debug("tdp_ratio %x\n", (int)tdp_ratio);
+
+               return (int)tdp_ratio;
+       }
+
+       return -ENXIO;
+}
+
 static int core_get_max_pstate(void)
 {
        u64 tar;
        u64 plat_info;
        int max_pstate;
+       int tdp_ratio;
        int err;
 
        rdmsrl(MSR_PLATFORM_INFO, plat_info);
        max_pstate = (plat_info >> 8) & 0xFF;
 
+       tdp_ratio = core_get_tdp_ratio(plat_info);
+       if (tdp_ratio <= 0)
+               return max_pstate;
+
+       if (hwp_active) {
+               /* Turbo activation ratio is not used on HWP platforms */
+               return tdp_ratio;
+       }
+
        err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
        if (!err) {
+               int tar_levels;
+
                /* Do some sanity checking for safety */
-               if (plat_info & 0x600000000) {
-                       u64 tdp_ctrl;
-                       u64 tdp_ratio;
-                       int tdp_msr;
-
-                       err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
-                       if (err)
-                               goto skip_tar;
-
-                       tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x3);
-                       err = rdmsrl_safe(tdp_msr, &tdp_ratio);
-                       if (err)
-                               goto skip_tar;
-
-                       /* For level 1 and 2, bits[23:16] contain the ratio */
-                       if (tdp_ctrl)
-                               tdp_ratio >>= 16;
-
-                       tdp_ratio &= 0xff; /* ratios are only 8 bits long */
-                       if (tdp_ratio - 1 == tar) {
-                               max_pstate = tar;
-                               pr_debug("max_pstate=TAC %x\n", max_pstate);
-                       } else {
-                               goto skip_tar;
-                       }
+               tar_levels = tar & 0xff;
+               if (tdp_ratio - 1 == tar_levels) {
+                       max_pstate = tar_levels;
+                       pr_debug("max_pstate=TAC %x\n", max_pstate);
                }
        }
 
-skip_tar:
        return max_pstate;
 }
 
@@ -1952,20 +2067,6 @@ static void intel_pstate_clear_update_util_hook(unsigned int cpu)
        synchronize_sched();
 }
 
-static void intel_pstate_set_performance_limits(struct perf_limits *limits)
-{
-       limits->no_turbo = 0;
-       limits->turbo_disabled = 0;
-       limits->max_perf_pct = 100;
-       limits->max_perf = int_ext_tofp(1);
-       limits->min_perf_pct = 100;
-       limits->min_perf = int_ext_tofp(1);
-       limits->max_policy_pct = 100;
-       limits->max_sysfs_pct = 100;
-       limits->min_policy_pct = 0;
-       limits->min_sysfs_pct = 0;
-}
-
 static void intel_pstate_update_perf_limits(struct cpufreq_policy *policy,
                                            struct perf_limits *limits)
 {
@@ -2072,6 +2173,20 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy)
 
 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
 {
+       struct cpudata *cpu = all_cpu_data[policy->cpu];
+       struct perf_limits *perf_limits;
+
+       if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
+               perf_limits = &performance_limits;
+       else
+               perf_limits = &powersave_limits;
+
+       update_turbo_state();
+       policy->cpuinfo.max_freq = perf_limits->turbo_disabled ||
+                                       perf_limits->no_turbo ?
+                                       cpu->pstate.max_freq :
+                                       cpu->pstate.turbo_freq;
+
        cpufreq_verify_within_cpu_limits(policy);
 
        if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
@@ -2299,6 +2414,116 @@ static struct cpufreq_driver intel_cpufreq = {
 
 static struct cpufreq_driver *intel_pstate_driver = &intel_pstate;
 
+static void intel_pstate_driver_cleanup(void)
+{
+       unsigned int cpu;
+
+       get_online_cpus();
+       for_each_online_cpu(cpu) {
+               if (all_cpu_data[cpu]) {
+                       if (intel_pstate_driver == &intel_pstate)
+                               intel_pstate_clear_update_util_hook(cpu);
+
+                       kfree(all_cpu_data[cpu]);
+                       all_cpu_data[cpu] = NULL;
+               }
+       }
+       put_online_cpus();
+}
+
+static int intel_pstate_register_driver(void)
+{
+       int ret;
+
+       intel_pstate_init_limits(&powersave_limits);
+       intel_pstate_set_performance_limits(&performance_limits);
+       limits = IS_ENABLED(CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE) ?
+                       &performance_limits : &powersave_limits;
+
+       ret = cpufreq_register_driver(intel_pstate_driver);
+       if (ret) {
+               intel_pstate_driver_cleanup();
+               return ret;
+       }
+
+       mutex_lock(&intel_pstate_limits_lock);
+       driver_registered = true;
+       mutex_unlock(&intel_pstate_limits_lock);
+
+       if (intel_pstate_driver == &intel_pstate && !hwp_active &&
+           pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
+               intel_pstate_debug_expose_params();
+
+       return 0;
+}
+
+static int intel_pstate_unregister_driver(void)
+{
+       if (hwp_active)
+               return -EBUSY;
+
+       if (intel_pstate_driver == &intel_pstate && !hwp_active &&
+           pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
+               intel_pstate_debug_hide_params();
+
+       mutex_lock(&intel_pstate_limits_lock);
+       driver_registered = false;
+       mutex_unlock(&intel_pstate_limits_lock);
+
+       cpufreq_unregister_driver(intel_pstate_driver);
+       intel_pstate_driver_cleanup();
+
+       return 0;
+}
+
+static ssize_t intel_pstate_show_status(char *buf)
+{
+       if (!driver_registered)
+               return sprintf(buf, "off\n");
+
+       return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
+                                       "active" : "passive");
+}
+
+static int intel_pstate_update_status(const char *buf, size_t size)
+{
+       int ret;
+
+       if (size == 3 && !strncmp(buf, "off", size))
+               return driver_registered ?
+                       intel_pstate_unregister_driver() : -EINVAL;
+
+       if (size == 6 && !strncmp(buf, "active", size)) {
+               if (driver_registered) {
+                       if (intel_pstate_driver == &intel_pstate)
+                               return 0;
+
+                       ret = intel_pstate_unregister_driver();
+                       if (ret)
+                               return ret;
+               }
+
+               intel_pstate_driver = &intel_pstate;
+               return intel_pstate_register_driver();
+       }
+
+       if (size == 7 && !strncmp(buf, "passive", size)) {
+               if (driver_registered) {
+                       if (intel_pstate_driver != &intel_pstate)
+                               return 0;
+
+                       ret = intel_pstate_unregister_driver();
+                       if (ret)
+                               return ret;
+               }
+
+               intel_pstate_driver = &intel_cpufreq;
+               return intel_pstate_register_driver();
+       }
+
+       return -EINVAL;
+}
+
 static int no_load __initdata;
 static int no_hwp __initdata;
 static int hwp_only __initdata;
@@ -2486,9 +2711,9 @@ static const struct x86_cpu_id hwp_support_ids[] __initconst = {
 
 static int __init intel_pstate_init(void)
 {
-       int cpu, rc = 0;
        const struct x86_cpu_id *id;
        struct cpu_defaults *cpu_def;
+       int rc = 0;
 
        if (no_load)
                return -ENODEV;
@@ -2520,45 +2745,29 @@ hwp_cpu_matched:
        if (intel_pstate_platform_pwr_mgmt_exists())
                return -ENODEV;
 
+       if (!hwp_active && hwp_only)
+               return -ENOTSUPP;
+
        pr_info("Intel P-state driver initializing\n");
 
        all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
        if (!all_cpu_data)
                return -ENOMEM;
 
-       if (!hwp_active && hwp_only)
-               goto out;
-
        intel_pstate_request_control_from_smm();
 
-       rc = cpufreq_register_driver(intel_pstate_driver);
-       if (rc)
-               goto out;
-
-       if (intel_pstate_driver == &intel_pstate && !hwp_active &&
-           pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
-               intel_pstate_debug_expose_params();
-
        intel_pstate_sysfs_expose_params();
 
+       mutex_lock(&intel_pstate_driver_lock);
+       rc = intel_pstate_register_driver();
+       mutex_unlock(&intel_pstate_driver_lock);
+       if (rc)
+               return rc;
+
        if (hwp_active)
                pr_info("HWP enabled\n");
 
-       return rc;
-out:
-       get_online_cpus();
-       for_each_online_cpu(cpu) {
-               if (all_cpu_data[cpu]) {
-                       if (intel_pstate_driver == &intel_pstate)
-                               intel_pstate_clear_update_util_hook(cpu);
-
-                       kfree(all_cpu_data[cpu]);
-               }
-       }
-
-       put_online_cpus();
-       vfree(all_cpu_data);
-       return -ENODEV;
+       return 0;
 }
 device_initcall(intel_pstate_init);