cpufreq:boost:Kconfig: Enable software managed BOOST support at Kconfig

For safety reasons new flag - CONFIG_CPU_FREQ_BOOST_SW has been added.
Only after selecting "CPU Frequency Overclocking - Software" Kconfig
option the software managed boost is enabled. It also requires thermal
subsystem to be compiled in. Thermal is necessary for disabling boost
and cooling down the device when overheating detected.

Boost _MUST_NOT_ be enabled without thermal subsystem with properly
defined temperatures which indicate overheating.

This option doesn't affect x86's ACPI hardware managed boost support
(i.e. Intel, AMD). In this situation boost management is embedded at
hardware.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Changes for v6:
- Remove platform dependency (EXYNOS_THERMAL) in selecting software
  managed boost. Now boost only depends on THERMAL.
- Remove CPUFREQ dependency
- Software boost Kconfig name has been edited

Changes for v5:
- New patch

diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 534fcb8..79ebd97 100644 (file)
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -23,6 +23,20 @@ config CPU_FREQ_TABLE
 config CPU_FREQ_GOV_COMMON
        bool
 
+config CPU_FREQ_BOOST_SW
+       bool "CPU Frequency Overclocking - Software"
+       depends on THERMAL
+       default n
+       help
+         This driver supports software managed overclocking (BOOST).
+         It allows usage of special frequencies for a particular processor
+         if thermal conditions are appropriate.
+
+         It reguires, for safe operation, thermal framework with properly
+         defined trip points.
+
+         If in doubt, say N.
+
 config CPU_FREQ_STAT
        tristate "CPU frequency translation statistics"
        select CPU_FREQ_TABLE

diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
index 3704b51..51a126c 100644 (file)
--- a/drivers/cpufreq/exynos-cpufreq.c
+++ b/drivers/cpufreq/exynos-cpufreq.c
@@ -405,7 +405,9 @@ static struct of_device_id exynos_cpufreq_of_match[] = {
 
 static int exynos_cpufreq_probe(struct platform_device *pdev)
 {
+#ifdef CONFIG_CPU_FREQ_BOOST_SW
        struct device_node *node = pdev->dev.of_node;
+#endif
        int ret = -EINVAL;
 
        exynos_info = kzalloc(sizeof(struct exynos_dvfs_info), GFP_KERNEL);
@@ -438,8 +440,10 @@ static int exynos_cpufreq_probe(struct platform_device *pdev)
        }
 
        locking_frequency = exynos_getspeed(0);
+#ifdef CONFIG_CPU_FREQ_BOOST_SW
        if (of_property_read_bool(node, "boost_mode"))
                exynos_driver.boost_supported = true;
+#endif
 
        register_pm_notifier(&exynos_cpufreq_nb);