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authorLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 15:21:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 15:21:02 -0700
commit3ed1c478eff8db80e234d5446cb378b503135888 (patch)
treee1c8e0f488ca49c49b5a31fe59add4254381dd4b /drivers/cpufreq/sh-cpufreq.c
parent151173e8ce9b95bbbbd7eedb9035cfaffbdb7cb2 (diff)
parent371deb9500831ad1afbf9ea00e373f650deaed2f (diff)
downloadblackbird-op-linux-3ed1c478eff8db80e234d5446cb378b503135888.tar.gz
blackbird-op-linux-3ed1c478eff8db80e234d5446cb378b503135888.zip
Merge tag 'pm+acpi-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael J Wysocki: - ARM big.LITTLE cpufreq driver from Viresh Kumar. - exynos5440 cpufreq driver from Amit Daniel Kachhap. - cpufreq core cleanup and code consolidation from Viresh Kumar and Stratos Karafotis. - cpufreq scalability improvement from Nathan Zimmer. - AMD "frequency sensitivity feedback" powersave bias for the ondemand cpufreq governor from Jacob Shin. - cpuidle code consolidation and cleanups from Daniel Lezcano. - ARM OMAP cpuidle fixes from Santosh Shilimkar and Daniel Lezcano. - ACPICA fixes and other improvements from Bob Moore, Jung-uk Kim, Lv Zheng, Yinghai Lu, Tang Chen, Colin Ian King, and Linn Crosetto. - ACPI core updates related to hotplug from Toshi Kani, Paul Bolle, Yasuaki Ishimatsu, and Rafael J Wysocki. - Intel Lynxpoint LPSS (Low-Power Subsystem) support improvements from Rafael J Wysocki and Andy Shevchenko. * tag 'pm+acpi-3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (192 commits) cpufreq: Revert incorrect commit 5800043 cpufreq: MAINTAINERS: Add co-maintainer cpuidle: add maintainer entry ACPI / thermal: do not always return THERMAL_TREND_RAISING for active trip points ARM: s3c64xx: cpuidle: use init/exit common routine cpufreq: pxa2xx: initialize variables ACPI: video: correct acpi_video_bus_add error processing SH: cpuidle: use init/exit common routine ARM: S5pv210: compiling issue, ARM_S5PV210_CPUFREQ needs CONFIG_CPU_FREQ_TABLE=y ACPI: Fix wrong parameter passed to memblock_reserve cpuidle: fix comment format pnp: use %*phC to dump small buffers isapnp: remove debug leftovers ARM: imx: cpuidle: use init/exit common routine ARM: davinci: cpuidle: use init/exit common routine ARM: kirkwood: cpuidle: use init/exit common routine ARM: calxeda: cpuidle: use init/exit common routine ARM: tegra: cpuidle: use init/exit common routine for tegra3 ARM: tegra: cpuidle: use init/exit common routine for tegra2 ARM: OMAP4: cpuidle: use init/exit common routine ...
Diffstat (limited to 'drivers/cpufreq/sh-cpufreq.c')
-rw-r--r--drivers/cpufreq/sh-cpufreq.c189
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/cpufreq/sh-cpufreq.c b/drivers/cpufreq/sh-cpufreq.c
new file mode 100644
index 000000000000..73adb64651e8
--- /dev/null
+++ b/drivers/cpufreq/sh-cpufreq.c
@@ -0,0 +1,189 @@
+/*
+ * cpufreq driver for the SuperH processors.
+ *
+ * Copyright (C) 2002 - 2012 Paul Mundt
+ * Copyright (C) 2002 M. R. Brown
+ *
+ * Clock framework bits from arch/avr32/mach-at32ap/cpufreq.c
+ *
+ * Copyright (C) 2004-2007 Atmel Corporation
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#define pr_fmt(fmt) "cpufreq: " fmt
+
+#include <linux/types.h>
+#include <linux/cpufreq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/cpumask.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/sched.h> /* set_cpus_allowed() */
+#include <linux/clk.h>
+#include <linux/percpu.h>
+#include <linux/sh_clk.h>
+
+static DEFINE_PER_CPU(struct clk, sh_cpuclk);
+
+static unsigned int sh_cpufreq_get(unsigned int cpu)
+{
+ return (clk_get_rate(&per_cpu(sh_cpuclk, cpu)) + 500) / 1000;
+}
+
+/*
+ * Here we notify other drivers of the proposed change and the final change.
+ */
+static int sh_cpufreq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int cpu = policy->cpu;
+ struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu);
+ cpumask_t cpus_allowed;
+ struct cpufreq_freqs freqs;
+ struct device *dev;
+ long freq;
+
+ cpus_allowed = current->cpus_allowed;
+ set_cpus_allowed_ptr(current, cpumask_of(cpu));
+
+ BUG_ON(smp_processor_id() != cpu);
+
+ dev = get_cpu_device(cpu);
+
+ /* Convert target_freq from kHz to Hz */
+ freq = clk_round_rate(cpuclk, target_freq * 1000);
+
+ if (freq < (policy->min * 1000) || freq > (policy->max * 1000))
+ return -EINVAL;
+
+ dev_dbg(dev, "requested frequency %u Hz\n", target_freq * 1000);
+
+ freqs.old = sh_cpufreq_get(cpu);
+ freqs.new = (freq + 500) / 1000;
+ freqs.flags = 0;
+
+ cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
+ set_cpus_allowed_ptr(current, &cpus_allowed);
+ clk_set_rate(cpuclk, freq);
+ cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
+
+ dev_dbg(dev, "set frequency %lu Hz\n", freq);
+
+ return 0;
+}
+
+static int sh_cpufreq_verify(struct cpufreq_policy *policy)
+{
+ struct clk *cpuclk = &per_cpu(sh_cpuclk, policy->cpu);
+ struct cpufreq_frequency_table *freq_table;
+
+ freq_table = cpuclk->nr_freqs ? cpuclk->freq_table : NULL;
+ if (freq_table)
+ return cpufreq_frequency_table_verify(policy, freq_table);
+
+ cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+ policy->cpuinfo.max_freq);
+
+ policy->min = (clk_round_rate(cpuclk, 1) + 500) / 1000;
+ policy->max = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000;
+
+ cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+ policy->cpuinfo.max_freq);
+
+ return 0;
+}
+
+static int sh_cpufreq_cpu_init(struct cpufreq_policy *policy)
+{
+ unsigned int cpu = policy->cpu;
+ struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu);
+ struct cpufreq_frequency_table *freq_table;
+ struct device *dev;
+
+ dev = get_cpu_device(cpu);
+
+ cpuclk = clk_get(dev, "cpu_clk");
+ if (IS_ERR(cpuclk)) {
+ dev_err(dev, "couldn't get CPU clk\n");
+ return PTR_ERR(cpuclk);
+ }
+
+ policy->cur = sh_cpufreq_get(cpu);
+
+ freq_table = cpuclk->nr_freqs ? cpuclk->freq_table : NULL;
+ if (freq_table) {
+ int result;
+
+ result = cpufreq_frequency_table_cpuinfo(policy, freq_table);
+ if (!result)
+ cpufreq_frequency_table_get_attr(freq_table, cpu);
+ } else {
+ dev_notice(dev, "no frequency table found, falling back "
+ "to rate rounding.\n");
+
+ policy->min = policy->cpuinfo.min_freq =
+ (clk_round_rate(cpuclk, 1) + 500) / 1000;
+ policy->max = policy->cpuinfo.max_freq =
+ (clk_round_rate(cpuclk, ~0UL) + 500) / 1000;
+ }
+
+ policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+
+ dev_info(dev, "CPU Frequencies - Minimum %u.%03u MHz, "
+ "Maximum %u.%03u MHz.\n",
+ policy->min / 1000, policy->min % 1000,
+ policy->max / 1000, policy->max % 1000);
+
+ return 0;
+}
+
+static int sh_cpufreq_cpu_exit(struct cpufreq_policy *policy)
+{
+ unsigned int cpu = policy->cpu;
+ struct clk *cpuclk = &per_cpu(sh_cpuclk, cpu);
+
+ cpufreq_frequency_table_put_attr(cpu);
+ clk_put(cpuclk);
+
+ return 0;
+}
+
+static struct freq_attr *sh_freq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver sh_cpufreq_driver = {
+ .owner = THIS_MODULE,
+ .name = "sh",
+ .get = sh_cpufreq_get,
+ .target = sh_cpufreq_target,
+ .verify = sh_cpufreq_verify,
+ .init = sh_cpufreq_cpu_init,
+ .exit = sh_cpufreq_cpu_exit,
+ .attr = sh_freq_attr,
+};
+
+static int __init sh_cpufreq_module_init(void)
+{
+ pr_notice("SuperH CPU frequency driver.\n");
+ return cpufreq_register_driver(&sh_cpufreq_driver);
+}
+
+static void __exit sh_cpufreq_module_exit(void)
+{
+ cpufreq_unregister_driver(&sh_cpufreq_driver);
+}
+
+module_init(sh_cpufreq_module_init);
+module_exit(sh_cpufreq_module_exit);
+
+MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_DESCRIPTION("cpufreq driver for SuperH");
+MODULE_LICENSE("GPL");
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