platform/x86/intel/uncore-freq: Move to uncore-frequency folder

Move the current driver from platform/x86/intel/uncore-frequency.c
to platform/x86/intel/uncore-frequency/uncore-frequency.c.

No functional changes are expected.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220204000306.2517447-2-srinivas.pandruvada@linux.intel.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

3 files changed, 480 insertions, 0 deletions

diff --git a/drivers/platform/x86/intel/uncore-frequency/Kconfig b/drivers/platform/x86/intel/uncore-frequency/Kconfig
new file mode 100644
index 000000000000..21b209124916
--- /dev/null
+++ b/drivers/platform/x86/intel/uncore-frequency/Kconfig
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Uncore Frquency control drivers
+#
+
+menu "Intel Uncore Frequency Control"
+	depends on X86_64 || COMPILE_TEST
+
+config INTEL_UNCORE_FREQ_CONTROL
+	tristate "Intel Uncore frequency control driver"
+	depends on X86_64
+	help
+	  This driver allows control of Uncore frequency limits on
+	  supported server platforms.
+
+	  Uncore frequency controls RING/LLC (last-level cache) clocks.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called intel-uncore-frequency.
+
+endmenu
diff --git a/drivers/platform/x86/intel/uncore-frequency/Makefile b/drivers/platform/x86/intel/uncore-frequency/Makefile
new file mode 100644
index 000000000000..e22186a480e2
--- /dev/null
+++ b/drivers/platform/x86/intel/uncore-frequency/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for linux/drivers/platform/x86/intel/uncore-frequency
+#
+
+obj-$(CONFIG_INTEL_UNCORE_FREQ_CONTROL)	+= intel-uncore-frequency.o
+intel-uncore-frequency-y		:= uncore-frequency.o
diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c
new file mode 100644
index 000000000000..4cd8254f2e40
--- /dev/null
+++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c
@@ -0,0 +1,452 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Uncore Frequency Setting
+ * Copyright (c) 2019, Intel Corporation.
+ * All rights reserved.
+ *
+ * Provide interface to set MSR 620 at a granularity of per die. On CPU online,
+ * one control CPU is identified per die to read/write limit. This control CPU
+ * is changed, if the CPU state is changed to offline. When the last CPU is
+ * offline in a die then remove the sysfs object for that die.
+ * The majority of actual code is related to sysfs create and read/write
+ * attributes.
+ *
+ * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
+ */
+
+#include <linux/cpu.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+
+#define MSR_UNCORE_RATIO_LIMIT			0x620
+#define UNCORE_FREQ_KHZ_MULTIPLIER		100000
+
+/**
+ * struct uncore_data -	Encapsulate all uncore data
+ * @stored_uncore_data:	Last user changed MSR 620 value, which will be restored
+ *			on system resume.
+ * @initial_min_freq_khz: Sampled minimum uncore frequency at driver init
+ * @initial_max_freq_khz: Sampled maximum uncore frequency at driver init
+ * @control_cpu:	Designated CPU for a die to read/write
+ * @valid:		Mark the data valid/invalid
+ *
+ * This structure is used to encapsulate all data related to uncore sysfs
+ * settings for a die/package.
+ */
+struct uncore_data {
+	struct kobject kobj;
+	struct completion kobj_unregister;
+	u64 stored_uncore_data;
+	u32 initial_min_freq_khz;
+	u32 initial_max_freq_khz;
+	int control_cpu;
+	bool valid;
+};
+
+#define to_uncore_data(a) container_of(a, struct uncore_data, kobj)
+
+/* Max instances for uncore data, one for each die */
+static int uncore_max_entries __read_mostly;
+/* Storage for uncore data for all instances */
+static struct uncore_data *uncore_instances;
+/* Root of the all uncore sysfs kobjs */
+static struct kobject *uncore_root_kobj;
+/* Stores the CPU mask of the target CPUs to use during uncore read/write */
+static cpumask_t uncore_cpu_mask;
+/* CPU online callback register instance */
+static enum cpuhp_state uncore_hp_state __read_mostly;
+/* Mutex to control all mutual exclusions */
+static DEFINE_MUTEX(uncore_lock);
+
+struct uncore_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct kobject *kobj,
+			struct attribute *attr, char *buf);
+	ssize_t (*store)(struct kobject *kobj,
+			 struct attribute *attr, const char *c, ssize_t count);
+};
+
+#define define_one_uncore_ro(_name) \
+static struct uncore_attr _name = \
+__ATTR(_name, 0444, show_##_name, NULL)
+
+#define define_one_uncore_rw(_name) \
+static struct uncore_attr _name = \
+__ATTR(_name, 0644, show_##_name, store_##_name)
+
+#define show_uncore_data(member_name)					\
+	static ssize_t show_##member_name(struct kobject *kobj,         \
+					  struct attribute *attr,	\
+					  char *buf)			\
+	{                                                               \
+		struct uncore_data *data = to_uncore_data(kobj);	\
+		return scnprintf(buf, PAGE_SIZE, "%u\n",		\
+				 data->member_name);			\
+	}								\
+	define_one_uncore_ro(member_name)
+
+show_uncore_data(initial_min_freq_khz);
+show_uncore_data(initial_max_freq_khz);
+
+/* Common function to read MSR 0x620 and read min/max */
+static int uncore_read_ratio(struct uncore_data *data, unsigned int *min,
+			     unsigned int *max)
+{
+	u64 cap;
+	int ret;
+
+	if (data->control_cpu < 0)
+		return -ENXIO;
+
+	ret = rdmsrl_on_cpu(data->control_cpu, MSR_UNCORE_RATIO_LIMIT, &cap);
+	if (ret)
+		return ret;
+
+	*max = (cap & 0x7F) * UNCORE_FREQ_KHZ_MULTIPLIER;
+	*min = ((cap & GENMASK(14, 8)) >> 8) * UNCORE_FREQ_KHZ_MULTIPLIER;
+
+	return 0;
+}
+
+/* Common function to set min/max ratios to be used by sysfs callbacks */
+static int uncore_write_ratio(struct uncore_data *data, unsigned int input,
+			      int set_max)
+{
+	int ret;
+	u64 cap;
+
+	mutex_lock(&uncore_lock);
+
+	if (data->control_cpu < 0) {
+		ret = -ENXIO;
+		goto finish_write;
+	}
+
+	input /= UNCORE_FREQ_KHZ_MULTIPLIER;
+	if (!input || input > 0x7F) {
+		ret = -EINVAL;
+		goto finish_write;
+	}
+
+	ret = rdmsrl_on_cpu(data->control_cpu, MSR_UNCORE_RATIO_LIMIT, &cap);
+	if (ret)
+		goto finish_write;
+
+	if (set_max) {
+		cap &= ~0x7F;
+		cap |= input;
+	} else  {
+		cap &= ~GENMASK(14, 8);
+		cap |= (input << 8);
+	}
+
+	ret = wrmsrl_on_cpu(data->control_cpu, MSR_UNCORE_RATIO_LIMIT, cap);
+	if (ret)
+		goto finish_write;
+
+	data->stored_uncore_data = cap;
+
+finish_write:
+	mutex_unlock(&uncore_lock);
+
+	return ret;
+}
+
+static ssize_t store_min_max_freq_khz(struct kobject *kobj,
+				      struct attribute *attr,
+				      const char *buf, ssize_t count,
+				      int min_max)
+{
+	struct uncore_data *data = to_uncore_data(kobj);
+	unsigned int input;
+
+	if (kstrtouint(buf, 10, &input))
+		return -EINVAL;
+
+	uncore_write_ratio(data, input, min_max);
+
+	return count;
+}
+
+static ssize_t show_min_max_freq_khz(struct kobject *kobj,
+				     struct attribute *attr,
+				     char *buf, int min_max)
+{
+	struct uncore_data *data = to_uncore_data(kobj);
+	unsigned int min, max;
+	int ret;
+
+	mutex_lock(&uncore_lock);
+	ret = uncore_read_ratio(data, &min, &max);
+	mutex_unlock(&uncore_lock);
+	if (ret)
+		return ret;
+
+	if (min_max)
+		return sprintf(buf, "%u\n", max);
+
+	return sprintf(buf, "%u\n", min);
+}
+
+#define store_uncore_min_max(name, min_max)				\
+	static ssize_t store_##name(struct kobject *kobj,		\
+				    struct attribute *attr,		\
+				    const char *buf, ssize_t count)	\
+	{                                                               \
+									\
+		return store_min_max_freq_khz(kobj, attr, buf, count,	\
+					      min_max);			\
+	}
+
+#define show_uncore_min_max(name, min_max)				\
+	static ssize_t show_##name(struct kobject *kobj,		\
+				   struct attribute *attr, char *buf)	\
+	{                                                               \
+									\
+		return show_min_max_freq_khz(kobj, attr, buf, min_max); \
+	}
+
+store_uncore_min_max(min_freq_khz, 0);
+store_uncore_min_max(max_freq_khz, 1);
+
+show_uncore_min_max(min_freq_khz, 0);
+show_uncore_min_max(max_freq_khz, 1);
+
+define_one_uncore_rw(min_freq_khz);
+define_one_uncore_rw(max_freq_khz);
+
+static struct attribute *uncore_attrs[] = {
+	&initial_min_freq_khz.attr,
+	&initial_max_freq_khz.attr,
+	&max_freq_khz.attr,
+	&min_freq_khz.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(uncore);
+
+static void uncore_sysfs_entry_release(struct kobject *kobj)
+{
+	struct uncore_data *data = to_uncore_data(kobj);
+
+	complete(&data->kobj_unregister);
+}
+
+static struct kobj_type uncore_ktype = {
+	.release = uncore_sysfs_entry_release,
+	.sysfs_ops = &kobj_sysfs_ops,
+	.default_groups = uncore_groups,
+};
+
+/* Caller provides protection */
+static struct uncore_data *uncore_get_instance(unsigned int cpu)
+{
+	int id = topology_logical_die_id(cpu);
+
+	if (id >= 0 && id < uncore_max_entries)
+		return &uncore_instances[id];
+
+	return NULL;
+}
+
+static void uncore_add_die_entry(int cpu)
+{
+	struct uncore_data *data;
+
+	mutex_lock(&uncore_lock);
+	data = uncore_get_instance(cpu);
+	if (!data) {
+		mutex_unlock(&uncore_lock);
+		return;
+	}
+
+	if (data->valid) {
+		/* control cpu changed */
+		data->control_cpu = cpu;
+	} else {
+		char str[64];
+		int ret;
+
+		memset(data, 0, sizeof(*data));
+		sprintf(str, "package_%02d_die_%02d",
+			topology_physical_package_id(cpu),
+			topology_die_id(cpu));
+
+		uncore_read_ratio(data, &data->initial_min_freq_khz,
+				  &data->initial_max_freq_khz);
+
+		init_completion(&data->kobj_unregister);
+
+		ret = kobject_init_and_add(&data->kobj, &uncore_ktype,
+					   uncore_root_kobj, str);
+		if (!ret) {
+			data->control_cpu = cpu;
+			data->valid = true;
+		}
+	}
+	mutex_unlock(&uncore_lock);
+}
+
+/* Last CPU in this die is offline, make control cpu invalid */
+static void uncore_remove_die_entry(int cpu)
+{
+	struct uncore_data *data;
+
+	mutex_lock(&uncore_lock);
+	data = uncore_get_instance(cpu);
+	if (data)
+		data->control_cpu = -1;
+	mutex_unlock(&uncore_lock);
+}
+
+static int uncore_event_cpu_online(unsigned int cpu)
+{
+	int target;
+
+	/* Check if there is an online cpu in the package for uncore MSR */
+	target = cpumask_any_and(&uncore_cpu_mask, topology_die_cpumask(cpu));
+	if (target < nr_cpu_ids)
+		return 0;
+
+	/* Use this CPU on this die as a control CPU */
+	cpumask_set_cpu(cpu, &uncore_cpu_mask);
+	uncore_add_die_entry(cpu);
+
+	return 0;
+}
+
+static int uncore_event_cpu_offline(unsigned int cpu)
+{
+	int target;
+
+	/* Check if existing cpu is used for uncore MSRs */
+	if (!cpumask_test_and_clear_cpu(cpu, &uncore_cpu_mask))
+		return 0;
+
+	/* Find a new cpu to set uncore MSR */
+	target = cpumask_any_but(topology_die_cpumask(cpu), cpu);
+
+	if (target < nr_cpu_ids) {
+		cpumask_set_cpu(target, &uncore_cpu_mask);
+		uncore_add_die_entry(target);
+	} else {
+		uncore_remove_die_entry(cpu);
+	}
+
+	return 0;
+}
+
+static int uncore_pm_notify(struct notifier_block *nb, unsigned long mode,
+			    void *_unused)
+{
+	int cpu;
+
+	switch (mode) {
+	case PM_POST_HIBERNATION:
+	case PM_POST_RESTORE:
+	case PM_POST_SUSPEND:
+		for_each_cpu(cpu, &uncore_cpu_mask) {
+			struct uncore_data *data;
+			int ret;
+
+			data = uncore_get_instance(cpu);
+			if (!data || !data->valid || !data->stored_uncore_data)
+				continue;
+
+			ret = wrmsrl_on_cpu(cpu, MSR_UNCORE_RATIO_LIMIT,
+					    data->stored_uncore_data);
+			if (ret)
+				return ret;
+		}
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static struct notifier_block uncore_pm_nb = {
+	.notifier_call = uncore_pm_notify,
+};
+
+static const struct x86_cpu_id intel_uncore_cpu_ids[] = {
+	X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_G,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_D,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D,	NULL),
+	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, NULL),
+	{}
+};
+
+static int __init intel_uncore_init(void)
+{
+	const struct x86_cpu_id *id;
+	int ret;
+
+	id = x86_match_cpu(intel_uncore_cpu_ids);
+	if (!id)
+		return -ENODEV;
+
+	uncore_max_entries = topology_max_packages() *
+					topology_max_die_per_package();
+	uncore_instances = kcalloc(uncore_max_entries,
+				   sizeof(*uncore_instances), GFP_KERNEL);
+	if (!uncore_instances)
+		return -ENOMEM;
+
+	uncore_root_kobj = kobject_create_and_add("intel_uncore_frequency",
+						  &cpu_subsys.dev_root->kobj);
+	if (!uncore_root_kobj) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
+
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+				"platform/x86/uncore-freq:online",
+				uncore_event_cpu_online,
+				uncore_event_cpu_offline);
+	if (ret < 0)
+		goto err_rem_kobj;
+
+	uncore_hp_state = ret;
+
+	ret = register_pm_notifier(&uncore_pm_nb);
+	if (ret)
+		goto err_rem_state;
+
+	return 0;
+
+err_rem_state:
+	cpuhp_remove_state(uncore_hp_state);
+err_rem_kobj:
+	kobject_put(uncore_root_kobj);
+err_free:
+	kfree(uncore_instances);
+
+	return ret;
+}
+module_init(intel_uncore_init)
+
+static void __exit intel_uncore_exit(void)
+{
+	int i;
+
+	unregister_pm_notifier(&uncore_pm_nb);
+	cpuhp_remove_state(uncore_hp_state);
+	for (i = 0; i < uncore_max_entries; ++i) {
+		if (uncore_instances[i].valid) {
+			kobject_put(&uncore_instances[i].kobj);
+			wait_for_completion(&uncore_instances[i].kobj_unregister);
+		}
+	}
+	kobject_put(uncore_root_kobj);
+	kfree(uncore_instances);
+}
+module_exit(intel_uncore_exit)
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel Uncore Frequency Limits Driver");