[PATCH] cpufreq: move frequency table helpers to extra module

The CPU frequency table helpers can easily be modularized --
especially as they are not needed on all architectures, or for
all drivers (even on x86 -- see longrun and gx-suspmod)

2 files changed, 205 insertions, 0 deletions

diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
new file mode 100644
index 000000000000..6be9f5e6998c
--- /dev/null
+++ b/drivers/cpufreq/Makefile
@@ -0,0 +1,2 @@
+#CPUfreq governors and cross-arch helpers
+obj-$(CONFIG_CPU_FREQ_TABLE)		+= freq_table.o
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
new file mode 100644
index 000000000000..8922d0d4a363
--- /dev/null
+++ b/drivers/cpufreq/freq_table.c
@@ -0,0 +1,203 @@
+/*
+ * linux/drivers/cpufreq/freq_table.c
+ *
+ * Copyright (C) 2002 - 2003 Dominik Brodowski
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+
+/*********************************************************************
+ *                     FREQUENCY TABLE HELPERS                       *
+ *********************************************************************/
+
+int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
+				    struct cpufreq_frequency_table *table)
+{
+	unsigned int min_freq = ~0;
+	unsigned int max_freq = 0;
+	unsigned int i = 0;
+
+	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
+		unsigned int freq = table[i].frequency;
+		if (freq == CPUFREQ_ENTRY_INVALID)
+			continue;
+		if (freq < min_freq)
+			min_freq = freq;
+		if (freq > max_freq)
+			max_freq = freq;
+	}
+
+	policy->min = policy->cpuinfo.min_freq = min_freq;
+	policy->max = policy->cpuinfo.max_freq = max_freq;
+
+	if (policy->min == ~0)
+		return -EINVAL;
+	else
+		return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
+
+
+int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
+				   struct cpufreq_frequency_table *table)
+{
+	unsigned int next_larger = ~0;
+	unsigned int i = 0;
+	unsigned int count = 0;
+
+	if (!cpu_online(policy->cpu))
+		return -EINVAL;
+
+	cpufreq_verify_within_limits(policy, 
+				     policy->cpuinfo.min_freq, 
+				     policy->cpuinfo.max_freq);
+
+	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
+		unsigned int freq = table[i].frequency;
+		if (freq == CPUFREQ_ENTRY_INVALID)
+			continue;
+		if ((freq >= policy->min) && (freq <= policy->max))
+			count++;
+		else if ((next_larger > freq) && (freq > policy->max))
+			next_larger = freq;
+	}
+
+	if (!count)
+		policy->max = next_larger;
+
+	cpufreq_verify_within_limits(policy, 
+				     policy->cpuinfo.min_freq, 
+				     policy->cpuinfo.max_freq);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
+
+
+int cpufreq_frequency_table_setpolicy(struct cpufreq_policy *policy,
+				      struct cpufreq_frequency_table *table,
+				      unsigned int *index)
+{
+	struct cpufreq_frequency_table optimal = { .index = ~0, };
+	unsigned int i;
+
+	switch (policy->policy) {
+	case CPUFREQ_POLICY_PERFORMANCE:
+		optimal.frequency = 0;
+		break;
+	case CPUFREQ_POLICY_POWERSAVE:
+		optimal.frequency = ~0;
+		break;
+	}
+
+	if (!cpu_online(policy->cpu))
+		return -EINVAL;
+
+	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
+		unsigned int freq = table[i].frequency;
+		if (freq == CPUFREQ_ENTRY_INVALID)
+			continue;
+		if ((freq < policy->min) || (freq > policy->max))
+			continue;
+		switch(policy->policy) {
+		case CPUFREQ_POLICY_PERFORMANCE:
+			if (optimal.frequency <= freq) {
+				optimal.frequency = freq;
+				optimal.index = i;
+			}
+			break;
+		case CPUFREQ_POLICY_POWERSAVE:
+			if (optimal.frequency >= freq) {
+				optimal.frequency = freq;
+				optimal.index = i;
+			}
+			break;
+		}
+	}
+	if (optimal.index > i)
+		return -EINVAL;
+
+	*index = optimal.index;
+	
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_setpolicy);
+
+
+int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
+				   struct cpufreq_frequency_table *table,
+				   unsigned int target_freq,
+				   unsigned int relation,
+				   unsigned int *index)
+{
+	struct cpufreq_frequency_table optimal = { .index = ~0, };
+	struct cpufreq_frequency_table suboptimal = { .index = ~0, };
+	unsigned int i;
+
+	switch (relation) {
+	case CPUFREQ_RELATION_H:
+		optimal.frequency = 0;
+		suboptimal.frequency = ~0;
+		break;
+	case CPUFREQ_RELATION_L:
+		optimal.frequency = ~0;
+		suboptimal.frequency = 0;
+		break;
+	}
+
+	if (!cpu_online(policy->cpu))
+		return -EINVAL;
+
+	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
+		unsigned int freq = table[i].frequency;
+		if (freq == CPUFREQ_ENTRY_INVALID)
+			continue;
+		if ((freq < policy->min) || (freq > policy->max))
+			continue;
+		switch(relation) {
+		case CPUFREQ_RELATION_H:
+			if (freq <= target_freq) {
+				if (freq >= optimal.frequency) {
+					optimal.frequency = freq;
+					optimal.index = i;
+				}
+			} else {
+				if (freq <= suboptimal.frequency) {
+					suboptimal.frequency = freq;
+					suboptimal.index = i;
+				}
+			}
+			break;
+		case CPUFREQ_RELATION_L:
+			if (freq >= target_freq) {
+				if (freq <= optimal.frequency) {
+					optimal.frequency = freq;
+					optimal.index = i;
+				}
+			} else {
+				if (freq >= suboptimal.frequency) {
+					suboptimal.frequency = freq;
+					suboptimal.index = i;
+				}
+			}
+			break;
+		}
+	}
+	if (optimal.index > i) {
+		if (suboptimal.index > i)
+			return -EINVAL;
+		*index = suboptimal.index;
+	} else
+		*index = optimal.index;
+	
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
+
+
+MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
+MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
+MODULE_LICENSE ("GPL");