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Diffstat (limited to 'ANDROID_3.4.5/drivers/cpufreq/db8500-cpufreq.c')
-rw-r--r--ANDROID_3.4.5/drivers/cpufreq/db8500-cpufreq.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/drivers/cpufreq/db8500-cpufreq.c b/ANDROID_3.4.5/drivers/cpufreq/db8500-cpufreq.c
new file mode 100644
index 00000000..0bf1b891
--- /dev/null
+++ b/ANDROID_3.4.5/drivers/cpufreq/db8500-cpufreq.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) STMicroelectronics 2009
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Sundar Iyer <sundar.iyer@stericsson.com>
+ * Author: Martin Persson <martin.persson@stericsson.com>
+ * Author: Jonas Aaberg <jonas.aberg@stericsson.com>
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/mfd/dbx500-prcmu.h>
+#include <mach/id.h>
+
+static struct cpufreq_frequency_table freq_table[] = {
+ [0] = {
+ .index = 0,
+ .frequency = 200000,
+ },
+ [1] = {
+ .index = 1,
+ .frequency = 400000,
+ },
+ [2] = {
+ .index = 2,
+ .frequency = 800000,
+ },
+ [3] = {
+ /* Used for MAX_OPP, if available */
+ .index = 3,
+ .frequency = CPUFREQ_TABLE_END,
+ },
+ [4] = {
+ .index = 4,
+ .frequency = CPUFREQ_TABLE_END,
+ },
+};
+
+static enum arm_opp idx2opp[] = {
+ ARM_EXTCLK,
+ ARM_50_OPP,
+ ARM_100_OPP,
+ ARM_MAX_OPP
+};
+
+static struct freq_attr *db8500_cpufreq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static int db8500_cpufreq_verify_speed(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, freq_table);
+}
+
+static int db8500_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ struct cpufreq_freqs freqs;
+ unsigned int idx;
+
+ /* scale the target frequency to one of the extremes supported */
+ if (target_freq < policy->cpuinfo.min_freq)
+ target_freq = policy->cpuinfo.min_freq;
+ if (target_freq > policy->cpuinfo.max_freq)
+ target_freq = policy->cpuinfo.max_freq;
+
+ /* Lookup the next frequency */
+ if (cpufreq_frequency_table_target
+ (policy, freq_table, target_freq, relation, &idx)) {
+ return -EINVAL;
+ }
+
+ freqs.old = policy->cur;
+ freqs.new = freq_table[idx].frequency;
+
+ if (freqs.old == freqs.new)
+ return 0;
+
+ /* pre-change notification */
+ for_each_cpu(freqs.cpu, policy->cpus)
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ /* request the PRCM unit for opp change */
+ if (prcmu_set_arm_opp(idx2opp[idx])) {
+ pr_err("db8500-cpufreq: Failed to set OPP level\n");
+ return -EINVAL;
+ }
+
+ /* post change notification */
+ for_each_cpu(freqs.cpu, policy->cpus)
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ return 0;
+}
+
+static unsigned int db8500_cpufreq_getspeed(unsigned int cpu)
+{
+ int i;
+ /* request the prcm to get the current ARM opp */
+ for (i = 0; prcmu_get_arm_opp() != idx2opp[i]; i++)
+ ;
+ return freq_table[i].frequency;
+}
+
+static int __cpuinit db8500_cpufreq_init(struct cpufreq_policy *policy)
+{
+ int i, res;
+
+ BUILD_BUG_ON(ARRAY_SIZE(idx2opp) + 1 != ARRAY_SIZE(freq_table));
+
+ if (prcmu_has_arm_maxopp())
+ freq_table[3].frequency = 1000000;
+
+ pr_info("db8500-cpufreq : Available frequencies:\n");
+ for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++)
+ pr_info(" %d Mhz\n", freq_table[i].frequency/1000);
+
+ /* get policy fields based on the table */
+ res = cpufreq_frequency_table_cpuinfo(policy, freq_table);
+ if (!res)
+ cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
+ else {
+ pr_err("db8500-cpufreq : Failed to read policy table\n");
+ return res;
+ }
+
+ policy->min = policy->cpuinfo.min_freq;
+ policy->max = policy->cpuinfo.max_freq;
+ policy->cur = db8500_cpufreq_getspeed(policy->cpu);
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+
+ /*
+ * FIXME : Need to take time measurement across the target()
+ * function with no/some/all drivers in the notification
+ * list.
+ */
+ policy->cpuinfo.transition_latency = 20 * 1000; /* in ns */
+
+ /* policy sharing between dual CPUs */
+ cpumask_copy(policy->cpus, cpu_present_mask);
+
+ policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
+
+ return 0;
+}
+
+static struct cpufreq_driver db8500_cpufreq_driver = {
+ .flags = CPUFREQ_STICKY,
+ .verify = db8500_cpufreq_verify_speed,
+ .target = db8500_cpufreq_target,
+ .get = db8500_cpufreq_getspeed,
+ .init = db8500_cpufreq_init,
+ .name = "DB8500",
+ .attr = db8500_cpufreq_attr,
+};
+
+static int __init db8500_cpufreq_register(void)
+{
+ if (!cpu_is_u8500v20_or_later())
+ return -ENODEV;
+
+ pr_info("cpufreq for DB8500 started\n");
+ return cpufreq_register_driver(&db8500_cpufreq_driver);
+}
+device_initcall(db8500_cpufreq_register);