Merge branch 'lsk-3.10-iks-cpufreq' of git://git.linaro.org/people/tixy/kernel into lsk-v3.10-tc2

drivers/clk/versatile/clk-vexpress-spc.c

@@ -102,7 +102,7 @@ struct clk *vexpress_clk_register_spc(const char *name, int cluster_id)
 #if defined(CONFIG_OF)
 void __init vexpress_clk_of_register_spc(void)
 {
-	char name[14] = "cpu-cluster.";
+	char name[14] = "cpu-cluster.X";
 	struct device_node *node = NULL;
 	struct clk *clk;
 	const u32 *val;

drivers/cpufreq/arm_big_little.c

@@ -24,27 +24,140 @@
 #include <linux/cpufreq.h>
 #include <linux/cpumask.h>
 #include <linux/export.h>
+#include <linux/mutex.h>
 #include <linux/of_platform.h>
 #include <linux/opp.h>
 #include <linux/slab.h>
 #include <linux/topology.h>
 #include <linux/types.h>
+#include <asm/bL_switcher.h>
 
 #include "arm_big_little.h"
 
-/* Currently we support only two clusters */
-#define MAX_CLUSTERS	2
+#ifdef CONFIG_BL_SWITCHER
+bool bL_switching_enabled;
+#endif
+
+#define ACTUAL_FREQ(cluster, freq)	((cluster == A7_CLUSTER) ? freq << 1 : freq)
+#define VIRT_FREQ(cluster, freq)	((cluster == A7_CLUSTER) ? freq >> 1 : freq)
 
 static struct cpufreq_arm_bL_ops *arm_bL_ops;
 static struct clk *clk[MAX_CLUSTERS];
-static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS];
-static atomic_t cluster_usage[MAX_CLUSTERS] = {ATOMIC_INIT(0), ATOMIC_INIT(0)};
+static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS + 1];
+static atomic_t cluster_usage[MAX_CLUSTERS + 1] = {ATOMIC_INIT(0),
+	ATOMIC_INIT(0)};
 
-static unsigned int bL_cpufreq_get(unsigned int cpu)
+static unsigned int clk_big_min;	/* (Big) clock frequencies */
+static unsigned int clk_little_max;	/* Maximum clock frequency (Little) */
+
+static DEFINE_PER_CPU(unsigned int, physical_cluster);
+static DEFINE_PER_CPU(unsigned int, cpu_last_req_freq);
+
+static struct mutex cluster_lock[MAX_CLUSTERS];
+
+static unsigned int find_cluster_maxfreq(int cluster)
 {
-	u32 cur_cluster = cpu_to_cluster(cpu);
+	int j;
+	u32 max_freq = 0, cpu_freq;
 
-	return clk_get_rate(clk[cur_cluster]) / 1000;
+	for_each_online_cpu(j) {
+		cpu_freq = per_cpu(cpu_last_req_freq, j);
+
+		if ((cluster == per_cpu(physical_cluster, j)) &&
+				(max_freq < cpu_freq))
+			max_freq = cpu_freq;
+	}
+
+	pr_debug("%s: cluster: %d, max freq: %d\n", __func__, cluster,
+			max_freq);
+
+	return max_freq;
+}
+
+static unsigned int clk_get_cpu_rate(unsigned int cpu)
+{
+	u32 cur_cluster = per_cpu(physical_cluster, cpu);
+	u32 rate = clk_get_rate(clk[cur_cluster]) / 1000;
+
+	/* For switcher we use virtual A15 clock rates */
+	if (is_bL_switching_enabled())
+		rate = VIRT_FREQ(cur_cluster, rate);
+
+	pr_debug("%s: cpu: %d, cluster: %d, freq: %u\n", __func__, cpu,
+			cur_cluster, rate);
+
+	return rate;
+}
+
+static unsigned int bL_cpufreq_get_rate(unsigned int cpu)
+{
+	pr_debug("%s: freq: %d\n", __func__, per_cpu(cpu_last_req_freq, cpu));
+
+	return per_cpu(cpu_last_req_freq, cpu);
+}
+
+static unsigned int
+bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate)
+{
+	u32 new_rate, prev_rate;
+	int ret;
+
+	mutex_lock(&cluster_lock[new_cluster]);
+
+	prev_rate = per_cpu(cpu_last_req_freq, cpu);
+	per_cpu(cpu_last_req_freq, cpu) = rate;
+	per_cpu(physical_cluster, cpu) = new_cluster;
+
+	if (is_bL_switching_enabled()) {
+		new_rate = find_cluster_maxfreq(new_cluster);
+		new_rate = ACTUAL_FREQ(new_cluster, new_rate);
+	} else {
+		new_rate = rate;
+	}
+
+	pr_debug("%s: cpu: %d, old cluster: %d, new cluster: %d, freq: %d\n",
+			__func__, cpu, old_cluster, new_cluster, new_rate);
+
+	ret = clk_set_rate(clk[new_cluster], new_rate * 1000);
+	if (WARN_ON(ret)) {
+		pr_err("clk_set_rate failed: %d, new cluster: %d\n", ret,
+				new_cluster);
+		per_cpu(cpu_last_req_freq, cpu) = prev_rate;
+		per_cpu(physical_cluster, cpu) = old_cluster;
+
+		mutex_unlock(&cluster_lock[new_cluster]);
+
+		return ret;
+	}
+
+	mutex_unlock(&cluster_lock[new_cluster]);
+
+	/* Recalc freq for old cluster when switching clusters */
+	if (old_cluster != new_cluster) {
+		pr_debug("%s: cpu: %d, old cluster: %d, new cluster: %d\n",
+				__func__, cpu, old_cluster, new_cluster);
+
+		/* Switch cluster */
+		bL_switch_request(cpu, new_cluster);
+
+		mutex_lock(&cluster_lock[old_cluster]);
+
+		/* Set freq of old cluster if there are cpus left on it */
+		new_rate = find_cluster_maxfreq(old_cluster);
+		new_rate = ACTUAL_FREQ(old_cluster, new_rate);
+
+		if (new_rate) {
+			pr_debug("%s: Updating rate of old cluster: %d, to freq: %d\n",
+					__func__, old_cluster, new_rate);
+
+			if (clk_set_rate(clk[old_cluster], new_rate * 1000))
+				pr_err("%s: clk_set_rate failed: %d, old cluster: %d\n",
+						__func__, ret, old_cluster);
+		}
+		mutex_unlock(&cluster_lock[old_cluster]);
+	}
+
+	return 0;
 }
 
 /* Validate policy frequency range */
@@ -60,12 +173,14 @@ static int bL_cpufreq_set_target(struct cpufreq_policy *policy,
 		unsigned int target_freq, unsigned int relation)
 {
 	struct cpufreq_freqs freqs;
-	u32 cpu = policy->cpu, freq_tab_idx, cur_cluster;
+	u32 cpu = policy->cpu, freq_tab_idx, cur_cluster, new_cluster,
+	    actual_cluster;
 	int ret = 0;
 
-	cur_cluster = cpu_to_cluster(policy->cpu);
+	cur_cluster = cpu_to_cluster(cpu);
+	new_cluster = actual_cluster = per_cpu(physical_cluster, cpu);
 
-	freqs.old = bL_cpufreq_get(policy->cpu);
+	freqs.old = bL_cpufreq_get_rate(cpu);
 
 	/* Determine valid target frequency using freq_table */
 	cpufreq_frequency_table_target(policy, freq_table[cur_cluster],
@@ -79,13 +194,21 @@ static int bL_cpufreq_set_target(struct cpufreq_policy *policy,
 	if (freqs.old == freqs.new)
 		return 0;
 
+	if (is_bL_switching_enabled()) {
+		if ((actual_cluster == A15_CLUSTER) &&
+				(freqs.new < clk_big_min)) {
+			new_cluster = A7_CLUSTER;
+		} else if ((actual_cluster == A7_CLUSTER) &&
+				(freqs.new > clk_little_max)) {
+			new_cluster = A15_CLUSTER;
+		}
+	}
+
 	cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
 
-	ret = clk_set_rate(clk[cur_cluster], freqs.new * 1000);
-	if (ret) {
-		pr_err("clk_set_rate failed: %d\n", ret);
+	ret = bL_cpufreq_set_rate(cpu, actual_cluster, new_cluster, freqs.new);
+	if (ret)
 		return ret;
-	}
 
 	policy->cur = freqs.new;
 
@@ -94,7 +217,73 @@ static int bL_cpufreq_set_target(struct cpufreq_policy *policy,
 	return ret;
 }
 
-static void put_cluster_clk_and_freq_table(struct device *cpu_dev)
+static inline u32 get_table_count(struct cpufreq_frequency_table *table)
+{
+	int count;
+
+	for (count = 0; table[count].frequency != CPUFREQ_TABLE_END; count++)
+		;
+
+	return count;
+}
+
+/* get the minimum frequency in the cpufreq_frequency_table */
+static inline u32 get_table_min(struct cpufreq_frequency_table *table)
+{
+	int i;
+	uint32_t min_freq = ~0;
+	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++)
+		if (table[i].frequency < min_freq)
+			min_freq = table[i].frequency;
+	return min_freq;
+}
+
+/* get the maximum frequency in the cpufreq_frequency_table */
+static inline u32 get_table_max(struct cpufreq_frequency_table *table)
+{
+	int i;
+	uint32_t max_freq = 0;
+	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++)
+		if (table[i].frequency > max_freq)
+			max_freq = table[i].frequency;
+	return max_freq;
+}
+
+static int merge_cluster_tables(void)
+{
+	int i, j, k = 0, count = 1;
+	struct cpufreq_frequency_table *table;
+
+	for (i = 0; i < MAX_CLUSTERS; i++)
+		count += get_table_count(freq_table[i]);
+
+	table = kzalloc(sizeof(*table) * count, GFP_KERNEL);
+	if (!table)
+		return -ENOMEM;
+
+	freq_table[MAX_CLUSTERS] = table;
+
+	/* Add in reverse order to get freqs in increasing order */
+	for (i = MAX_CLUSTERS - 1; i >= 0; i--) {
+		for (j = 0; freq_table[i][j].frequency != CPUFREQ_TABLE_END;
+				j++) {
+			table[k].frequency = VIRT_FREQ(i,
+					freq_table[i][j].frequency);
+			pr_debug("%s: index: %d, freq: %d\n", __func__, k,
+					table[k].frequency);
+			k++;
+		}
+	}
+
+	table[k].index = k;
+	table[k].frequency = CPUFREQ_TABLE_END;
+
+	pr_debug("%s: End, table: %p, count: %d\n", __func__, table, k);
+
+	return 0;
+}
+
+static void _put_cluster_clk_and_freq_table(struct device *cpu_dev)
 {
 	u32 cluster = cpu_to_cluster(cpu_dev->id);
 
@@ -105,10 +294,35 @@ static void put_cluster_clk_and_freq_table(struct device *cpu_dev)
 	}
 }
 
-static int get_cluster_clk_and_freq_table(struct device *cpu_dev)
+static void put_cluster_clk_and_freq_table(struct device *cpu_dev)
 {
 	u32 cluster = cpu_to_cluster(cpu_dev->id);
-	char name[14] = "cpu-cluster.";
+	int i;
+
+	if (cluster < MAX_CLUSTERS)
+		return _put_cluster_clk_and_freq_table(cpu_dev);
+
+	if (atomic_dec_return(&cluster_usage[MAX_CLUSTERS]))
+		return;
+
+	for (i = 0; i < MAX_CLUSTERS; i++) {
+		struct device *cdev = get_cpu_device(i);
+		if (!cdev) {
+			pr_err("%s: failed to get cpu%d device\n", __func__, i);
+			return;
+		}
+
+		_put_cluster_clk_and_freq_table(cdev);
+	}
+
+	/* free virtual table */
+	kfree(freq_table[MAX_CLUSTERS]);
+}
+
+static int _get_cluster_clk_and_freq_table(struct device *cpu_dev)
+{
+	u32 cluster = cpu_to_cluster(cpu_dev->id);
+	char name[14] = "cpu-cluster.X";
 	int ret;
 
 	if (atomic_inc_return(&cluster_usage[cluster]) != 1)
@@ -149,6 +363,62 @@ atomic_dec:
 	return ret;
 }
 
+static int get_cluster_clk_and_freq_table(struct device *cpu_dev)
+{
+	u32 cluster = cpu_to_cluster(cpu_dev->id);
+	int i, ret;
+
+	if (cluster < MAX_CLUSTERS)
+		return _get_cluster_clk_and_freq_table(cpu_dev);
+
+	if (atomic_inc_return(&cluster_usage[MAX_CLUSTERS]) != 1)
+		return 0;
+
+	/*
+	 * Get data for all clusters and fill virtual cluster with a merge of
+	 * both
+	 */
+	for (i = 0; i < MAX_CLUSTERS; i++) {
+		struct device *cdev = get_cpu_device(i);
+		if (!cdev) {
+			pr_err("%s: failed to get cpu%d device\n", __func__, i);
+			return -ENODEV;
+		}
+
+		ret = _get_cluster_clk_and_freq_table(cdev);
+		if (ret)
+			goto put_clusters;
+	}
+
+	ret = merge_cluster_tables();
+	if (ret)
+		goto put_clusters;
+
+	/* Assuming 2 cluster, set clk_big_min and clk_little_max */
+	clk_big_min = get_table_min(freq_table[0]);
+	clk_little_max = VIRT_FREQ(1, get_table_max(freq_table[1]));
+
+	pr_debug("%s: cluster: %d, clk_big_min: %d, clk_little_max: %d\n",
+			__func__, cluster, clk_big_min, clk_little_max);
+
+	return 0;
+
+put_clusters:
+	while (i--) {
+		struct device *cdev = get_cpu_device(i);
+		if (!cdev) {
+			pr_err("%s: failed to get cpu%d device\n", __func__, i);
+			return -ENODEV;
+		}
+
+		_put_cluster_clk_and_freq_table(cdev);
+	}
+
+	atomic_dec(&cluster_usage[MAX_CLUSTERS]);
+
+	return ret;
+}
+
 /* Per-CPU initialization */
 static int bL_cpufreq_init(struct cpufreq_policy *policy)
 {
@@ -177,37 +447,28 @@ static int bL_cpufreq_init(struct cpufreq_policy *policy)
 
 	cpufreq_frequency_table_get_attr(freq_table[cur_cluster], policy->cpu);
 
+	if (cur_cluster < MAX_CLUSTERS) {
+		cpumask_copy(policy->cpus, topology_core_cpumask(policy->cpu));
+
+		per_cpu(physical_cluster, policy->cpu) = cur_cluster;
+	} else {
+		/* Assumption: during init, we are always running on A15 */
+		per_cpu(physical_cluster, policy->cpu) = A15_CLUSTER;
+	}
+
 	if (arm_bL_ops->get_transition_latency)
 		policy->cpuinfo.transition_latency =
 			arm_bL_ops->get_transition_latency(cpu_dev);
 	else
 		policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
 
-	policy->cur = bL_cpufreq_get(policy->cpu);
-
-	cpumask_copy(policy->cpus, topology_core_cpumask(policy->cpu));
+	policy->cur = clk_get_cpu_rate(policy->cpu);
+	per_cpu(cpu_last_req_freq, policy->cpu) = policy->cur;
 
 	dev_info(cpu_dev, "%s: CPU %d initialized\n", __func__, policy->cpu);
 	return 0;
 }
 
-static int bL_cpufreq_exit(struct cpufreq_policy *policy)
-{
-	struct device *cpu_dev;
-
-	cpu_dev = get_cpu_device(policy->cpu);
-	if (!cpu_dev) {
-		pr_err("%s: failed to get cpu%d device\n", __func__,
-				policy->cpu);
-		return -ENODEV;
-	}
-
-	put_cluster_clk_and_freq_table(cpu_dev);
-	dev_dbg(cpu_dev, "%s: Exited, cpu: %d\n", __func__, policy->cpu);
-
-	return 0;
-}
-
 /* Export freq_table to sysfs */
 static struct freq_attr *bL_cpufreq_attr[] = {
 	&cpufreq_freq_attr_scaling_available_freqs,
@@ -219,16 +480,47 @@ static struct cpufreq_driver bL_cpufreq_driver = {
 	.flags			= CPUFREQ_STICKY,
 	.verify			= bL_cpufreq_verify_policy,
 	.target			= bL_cpufreq_set_target,
-	.get			= bL_cpufreq_get,
+	.get			= bL_cpufreq_get_rate,
 	.init			= bL_cpufreq_init,
-	.exit			= bL_cpufreq_exit,
 	.have_governor_per_policy = true,
 	.attr			= bL_cpufreq_attr,
 };
 
+static int bL_cpufreq_switcher_notifier(struct notifier_block *nfb,
+					unsigned long action, void *_arg)
+{
+	pr_debug("%s: action: %ld\n", __func__, action);
+
+	switch (action) {
+	case BL_NOTIFY_PRE_ENABLE:
+	case BL_NOTIFY_PRE_DISABLE:
+		cpufreq_unregister_driver(&bL_cpufreq_driver);
+		break;
+
+	case BL_NOTIFY_POST_ENABLE:
+		set_switching_enabled(true);
+		cpufreq_register_driver(&bL_cpufreq_driver);
+		break;
+
+	case BL_NOTIFY_POST_DISABLE:
+		set_switching_enabled(false);
+		cpufreq_register_driver(&bL_cpufreq_driver);
+		break;
+
+	default:
+		return NOTIFY_DONE;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block bL_switcher_notifier = {
+	.notifier_call = bL_cpufreq_switcher_notifier,
+};
+
 int bL_cpufreq_register(struct cpufreq_arm_bL_ops *ops)
 {
-	int ret;
+	int ret, i;
 
 	if (arm_bL_ops) {
 		pr_debug("%s: Already registered: %s, exiting\n", __func__,
@@ -243,16 +535,29 @@ int bL_cpufreq_register(struct cpufreq_arm_bL_ops *ops)
 
 	arm_bL_ops = ops;
 
+	ret = bL_switcher_get_enabled();
+	set_switching_enabled(ret);
+
+	for (i = 0; i < MAX_CLUSTERS; i++)
+		mutex_init(&cluster_lock[i]);
+
 	ret = cpufreq_register_driver(&bL_cpufreq_driver);
 	if (ret) {
 		pr_info("%s: Failed registering platform driver: %s, err: %d\n",
 				__func__, ops->name, ret);
 		arm_bL_ops = NULL;
 	} else {
-		pr_info("%s: Registered platform driver: %s\n", __func__,
-				ops->name);
+		ret = bL_switcher_register_notifier(&bL_switcher_notifier);
+		if (ret) {
+			cpufreq_unregister_driver(&bL_cpufreq_driver);
+			arm_bL_ops = NULL;
+		} else {
+			pr_info("%s: Registered platform driver: %s\n",
+					__func__, ops->name);
+		}
 	}
 
+	bL_switcher_put_enabled();
 	return ret;
 }
 EXPORT_SYMBOL_GPL(bL_cpufreq_register);
@@ -265,9 +570,31 @@ void bL_cpufreq_unregister(struct cpufreq_arm_bL_ops *ops)
 		return;
 	}
 
+	bL_switcher_get_enabled();
+	bL_switcher_unregister_notifier(&bL_switcher_notifier);
 	cpufreq_unregister_driver(&bL_cpufreq_driver);
+	bL_switcher_put_enabled();
 	pr_info("%s: Un-registered platform driver: %s\n", __func__,
 			arm_bL_ops->name);
+
+	/* For saving table get/put on every cpu in/out */
+	if (is_bL_switching_enabled()) {
+		put_cluster_clk_and_freq_table(get_cpu_device(0));
+	} else {
+		int i;
+
+		for (i = 0; i < MAX_CLUSTERS; i++) {
+			struct device *cdev = get_cpu_device(i);
+			if (!cdev) {
+				pr_err("%s: failed to get cpu%d device\n",
+						__func__, i);
+				return;
+			}
+
+			put_cluster_clk_and_freq_table(cdev);
+		}
+	}
+
 	arm_bL_ops = NULL;
 }
 EXPORT_SYMBOL_GPL(bL_cpufreq_unregister);

drivers/cpufreq/arm_big_little.h

@@ -23,6 +23,20 @@
 #include <linux/device.h>
 #include <linux/types.h>
 
+/* Currently we support only two clusters */
+#define A15_CLUSTER	0
+#define A7_CLUSTER	1
+#define MAX_CLUSTERS	2
+
+#ifdef CONFIG_BL_SWITCHER
+extern bool bL_switching_enabled;
+#define is_bL_switching_enabled()		bL_switching_enabled
+#define set_switching_enabled(x) 		(bL_switching_enabled = (x))
+#else
+#define is_bL_switching_enabled()		false
+#define set_switching_enabled(x) 		do { } while (0)
+#endif
+
 struct cpufreq_arm_bL_ops {
 	char name[CPUFREQ_NAME_LEN];
 	int (*get_transition_latency)(struct device *cpu_dev);
@@ -36,7 +50,8 @@ struct cpufreq_arm_bL_ops {
 
 static inline int cpu_to_cluster(int cpu)
 {
-	return topology_physical_package_id(cpu);
+	return is_bL_switching_enabled() ? MAX_CLUSTERS:
+		topology_physical_package_id(cpu);
 }
 
 int bL_cpufreq_register(struct cpufreq_arm_bL_ops *ops);

drivers/cpufreq/cpufreq_stats.c

@@ -21,6 +21,7 @@
 #include <linux/spinlock.h>
 #include <linux/notifier.h>
 #include <asm/cputime.h>
+#include <asm/bL_switcher.h>
 
 static spinlock_t cpufreq_stats_lock;
 
@@ -379,7 +380,7 @@ static struct notifier_block notifier_trans_block = {
 	.notifier_call = cpufreq_stat_notifier_trans
 };
 
-static int __init cpufreq_stats_init(void)
+static int cpufreq_stats_setup(void)
 {
 	int ret;
 	unsigned int cpu;
@@ -407,7 +408,8 @@ static int __init cpufreq_stats_init(void)
 
 	return 0;
 }
-static void __exit cpufreq_stats_exit(void)
+
+static void cpufreq_stats_cleanup(void)
 {
 	unsigned int cpu;
 
@@ -422,6 +424,49 @@ static void __exit cpufreq_stats_exit(void)
 	}
 }
 
+static int cpufreq_stats_switcher_notifier(struct notifier_block *nfb,
+					unsigned long action, void *_arg)
+{
+	switch (action) {
+	case BL_NOTIFY_PRE_ENABLE:
+	case BL_NOTIFY_PRE_DISABLE:
+		cpufreq_stats_cleanup();
+		break;
+
+	case BL_NOTIFY_POST_ENABLE:
+	case BL_NOTIFY_POST_DISABLE:
+		cpufreq_stats_setup();
+		break;
+
+	default:
+		return NOTIFY_DONE;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block switcher_notifier = {
+	.notifier_call = cpufreq_stats_switcher_notifier,
+};
+
+static int __init cpufreq_stats_init(void)
+{
+	int ret;
+	spin_lock_init(&cpufreq_stats_lock);
+
+	ret = cpufreq_stats_setup();
+	if (!ret)
+		bL_switcher_register_notifier(&switcher_notifier);
+
+	return ret;
+}
+
+static void __exit cpufreq_stats_exit(void)
+{
+	bL_switcher_unregister_notifier(&switcher_notifier);
+	cpufreq_stats_cleanup();
+}
+
 MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
 MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
 				"through sysfs filesystem");