Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/cpufreq/cpufreq_userspace.c b/drivers/cpufreq/cpufreq_userspace.c
new file mode 100644
index 0000000..d32bf35
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_userspace.c
@@ -0,0 +1,207 @@
+/*
+ * linux/drivers/cpufreq/cpufreq_userspace.c
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/cpufreq.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/sysfs.h>
+
+#include <asm/uaccess.h>
+
+
+/**
+ * A few values needed by the userspace governor
+ */
+static unsigned int cpu_max_freq[NR_CPUS];
+static unsigned int cpu_min_freq[NR_CPUS];
+static unsigned int cpu_cur_freq[NR_CPUS]; /* current CPU freq */
+static unsigned int cpu_set_freq[NR_CPUS]; /* CPU freq desired by userspace */
+static unsigned int cpu_is_managed[NR_CPUS];
+static struct cpufreq_policy current_policy[NR_CPUS];
+
+static DECLARE_MUTEX (userspace_sem);
+
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "userspace", msg)
+
+/* keep track of frequency transitions */
+static int
+userspace_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct cpufreq_freqs *freq = data;
+
+ dprintk("saving cpu_cur_freq of cpu %u to be %u kHz\n", freq->cpu, freq->new);
+ cpu_cur_freq[freq->cpu] = freq->new;
+
+ return 0;
+}
+
+static struct notifier_block userspace_cpufreq_notifier_block = {
+ .notifier_call = userspace_cpufreq_notifier
+};
+
+
+/**
+ * cpufreq_set - set the CPU frequency
+ * @freq: target frequency in kHz
+ * @cpu: CPU for which the frequency is to be set
+ *
+ * Sets the CPU frequency to freq.
+ */
+static int cpufreq_set(unsigned int freq, unsigned int cpu)
+{
+ int ret = -EINVAL;
+
+ dprintk("cpufreq_set for cpu %u, freq %u kHz\n", cpu, freq);
+
+ down(&userspace_sem);
+ if (!cpu_is_managed[cpu])
+ goto err;
+
+ cpu_set_freq[cpu] = freq;
+
+ if (freq < cpu_min_freq[cpu])
+ freq = cpu_min_freq[cpu];
+ if (freq > cpu_max_freq[cpu])
+ freq = cpu_max_freq[cpu];
+
+ /*
+ * We're safe from concurrent calls to ->target() here
+ * as we hold the userspace_sem lock. If we were calling
+ * cpufreq_driver_target, a deadlock situation might occur:
+ * A: cpufreq_set (lock userspace_sem) -> cpufreq_driver_target(lock policy->lock)
+ * B: cpufreq_set_policy(lock policy->lock) -> __cpufreq_governor -> cpufreq_governor_userspace (lock userspace_sem)
+ */
+ ret = __cpufreq_driver_target(¤t_policy[cpu], freq,
+ CPUFREQ_RELATION_L);
+
+ err:
+ up(&userspace_sem);
+ return ret;
+}
+
+
+/************************** sysfs interface ************************/
+static ssize_t show_speed (struct cpufreq_policy *policy, char *buf)
+{
+ return sprintf (buf, "%u\n", cpu_cur_freq[policy->cpu]);
+}
+
+static ssize_t
+store_speed (struct cpufreq_policy *policy, const char *buf, size_t count)
+{
+ unsigned int freq = 0;
+ unsigned int ret;
+
+ ret = sscanf (buf, "%u", &freq);
+ if (ret != 1)
+ return -EINVAL;
+
+ cpufreq_set(freq, policy->cpu);
+
+ return count;
+}
+
+static struct freq_attr freq_attr_scaling_setspeed =
+{
+ .attr = { .name = "scaling_setspeed", .mode = 0644, .owner = THIS_MODULE },
+ .show = show_speed,
+ .store = store_speed,
+};
+
+static int cpufreq_governor_userspace(struct cpufreq_policy *policy,
+ unsigned int event)
+{
+ unsigned int cpu = policy->cpu;
+ switch (event) {
+ case CPUFREQ_GOV_START:
+ if (!cpu_online(cpu))
+ return -EINVAL;
+ BUG_ON(!policy->cur);
+ down(&userspace_sem);
+ cpu_is_managed[cpu] = 1;
+ cpu_min_freq[cpu] = policy->min;
+ cpu_max_freq[cpu] = policy->max;
+ cpu_cur_freq[cpu] = policy->cur;
+ cpu_set_freq[cpu] = policy->cur;
+ sysfs_create_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
+ memcpy (¤t_policy[cpu], policy, sizeof(struct cpufreq_policy));
+ dprintk("managing cpu %u started (%u - %u kHz, currently %u kHz)\n", cpu, cpu_min_freq[cpu], cpu_max_freq[cpu], cpu_cur_freq[cpu]);
+ up(&userspace_sem);
+ break;
+ case CPUFREQ_GOV_STOP:
+ down(&userspace_sem);
+ cpu_is_managed[cpu] = 0;
+ cpu_min_freq[cpu] = 0;
+ cpu_max_freq[cpu] = 0;
+ cpu_set_freq[cpu] = 0;
+ sysfs_remove_file (&policy->kobj, &freq_attr_scaling_setspeed.attr);
+ dprintk("managing cpu %u stopped\n", cpu);
+ up(&userspace_sem);
+ break;
+ case CPUFREQ_GOV_LIMITS:
+ down(&userspace_sem);
+ cpu_min_freq[cpu] = policy->min;
+ cpu_max_freq[cpu] = policy->max;
+ dprintk("limit event for cpu %u: %u - %u kHz, currently %u kHz, last set to %u kHz\n", cpu, cpu_min_freq[cpu], cpu_max_freq[cpu], cpu_cur_freq[cpu], cpu_set_freq[cpu]);
+ if (policy->max < cpu_set_freq[cpu]) {
+ __cpufreq_driver_target(¤t_policy[cpu], policy->max,
+ CPUFREQ_RELATION_H);
+ } else if (policy->min > cpu_set_freq[cpu]) {
+ __cpufreq_driver_target(¤t_policy[cpu], policy->min,
+ CPUFREQ_RELATION_L);
+ } else {
+ __cpufreq_driver_target(¤t_policy[cpu], cpu_set_freq[cpu],
+ CPUFREQ_RELATION_L);
+ }
+ memcpy (¤t_policy[cpu], policy, sizeof(struct cpufreq_policy));
+ up(&userspace_sem);
+ break;
+ }
+ return 0;
+}
+
+
+struct cpufreq_governor cpufreq_gov_userspace = {
+ .name = "userspace",
+ .governor = cpufreq_governor_userspace,
+ .owner = THIS_MODULE,
+};
+EXPORT_SYMBOL(cpufreq_gov_userspace);
+
+static int __init cpufreq_gov_userspace_init(void)
+{
+ cpufreq_register_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
+ return cpufreq_register_governor(&cpufreq_gov_userspace);
+}
+
+
+static void __exit cpufreq_gov_userspace_exit(void)
+{
+ cpufreq_unregister_governor(&cpufreq_gov_userspace);
+ cpufreq_unregister_notifier(&userspace_cpufreq_notifier_block, CPUFREQ_TRANSITION_NOTIFIER);
+}
+
+
+MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>, Russell King <rmk@arm.linux.org.uk>");
+MODULE_DESCRIPTION ("CPUfreq policy governor 'userspace'");
+MODULE_LICENSE ("GPL");
+
+fs_initcall(cpufreq_gov_userspace_init);
+module_exit(cpufreq_gov_userspace_exit);
