From 27e289dce29764e488c1e13e9aa6950cad1f4aab Mon Sep 17 00:00:00 2001 From: Stratos Karafotis Date: Fri, 25 Apr 2014 23:15:23 +0300 Subject: cpufreq: Introduce macros for cpufreq_frequency_table iteration Many cpufreq drivers need to iterate over the cpufreq_frequency_table for various tasks. This patch introduces two macros which can be used for iteration over cpufreq_frequency_table keeping a common coding style across drivers: - cpufreq_for_each_entry: iterate over each entry of the table - cpufreq_for_each_valid_entry: iterate over each entry that contains a valid frequency. It should have no functional changes. Signed-off-by: Stratos Karafotis Acked-by: Lad, Prabhakar Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- Documentation/cpu-freq/cpu-drivers.txt | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'Documentation/cpu-freq') diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt index 48da5fdcb9f1..b045fe54986a 100644 --- a/Documentation/cpu-freq/cpu-drivers.txt +++ b/Documentation/cpu-freq/cpu-drivers.txt @@ -228,3 +228,22 @@ is the corresponding frequency table helper for the ->target stage. Just pass the values to this function, and the unsigned int index returns the number of the frequency table entry which contains the frequency the CPU shall be set to. + +The following macros can be used as iterators over cpufreq_frequency_table: + +cpufreq_for_each_entry(pos, table) - iterates over all entries of frequency +table. + +cpufreq-for_each_valid_entry(pos, table) - iterates over all entries, +excluding CPUFREQ_ENTRY_INVALID frequencies. +Use arguments "pos" - a cpufreq_frequency_table * as a loop cursor and +"table" - the cpufreq_frequency_table * you want to iterate over. + +For example: + + struct cpufreq_frequency_table *pos, *driver_freq_table; + + cpufreq_for_each_entry(pos, driver_freq_table) { + /* Do something with pos */ + pos->frequency = ... + } -- cgit v1.2.3 From dec102aa9ac112d66133314815d20233c96ad749 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 22 Apr 2014 10:42:05 +0530 Subject: cpufreq: Make linux-pm@vger.kernel.org official mailing list There has been confusion all the time about which mailing list to follow for cpufreq activities, linux-pm@vger.kernel.org or cpufreq@vger.kernel.org. Since patches sent to cpufreq@vger.kernel.org don't go to Patchwork which is a maintenance workflow problem, make linux-pm@vger.kernel.org the official mailing list for cpufreq stuff and remove all references of cpufreq@vger.kernel.org from kernel source. Later, we can request that the list be dropped entirely. Signed-off-by: Viresh Kumar [rjw: Changelog] Signed-off-by: Rafael J. Wysocki --- Documentation/ABI/testing/sysfs-devices-system-cpu | 4 ++-- Documentation/cpu-freq/index.txt | 4 ++-- MAINTAINERS | 2 -- drivers/cpufreq/speedstep-centrino.c | 2 +- tools/power/cpupower/Makefile | 2 +- tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c | 2 +- 6 files changed, 7 insertions(+), 9 deletions(-) (limited to 'Documentation/cpu-freq') diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index d5a0d33c571f..acb9bfc89b48 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -128,7 +128,7 @@ Description: Discover cpuidle policy and mechanism What: /sys/devices/system/cpu/cpu#/cpufreq/* Date: pre-git history -Contact: cpufreq@vger.kernel.org +Contact: linux-pm@vger.kernel.org Description: Discover and change clock speed of CPUs Clock scaling allows you to change the clock speed of the @@ -146,7 +146,7 @@ Description: Discover and change clock speed of CPUs What: /sys/devices/system/cpu/cpu#/cpufreq/freqdomain_cpus Date: June 2013 -Contact: cpufreq@vger.kernel.org +Contact: linux-pm@vger.kernel.org Description: Discover CPUs in the same CPU frequency coordination domain freqdomain_cpus is the list of CPUs (online+offline) that share diff --git a/Documentation/cpu-freq/index.txt b/Documentation/cpu-freq/index.txt index 3d0b915035b9..dc024ab4054f 100644 --- a/Documentation/cpu-freq/index.txt +++ b/Documentation/cpu-freq/index.txt @@ -35,8 +35,8 @@ Mailing List ------------ There is a CPU frequency changing CVS commit and general list where you can report bugs, problems or submit patches. To post a message, -send an email to cpufreq@vger.kernel.org, to subscribe go to -http://vger.kernel.org/vger-lists.html#cpufreq and follow the +send an email to linux-pm@vger.kernel.org, to subscribe go to +http://vger.kernel.org/vger-lists.html#linux-pm and follow the instructions there. Links diff --git a/MAINTAINERS b/MAINTAINERS index e67ea2442041..433163dd9351 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2415,7 +2415,6 @@ F: drivers/net/ethernet/ti/cpmac.c CPU FREQUENCY DRIVERS M: Rafael J. Wysocki M: Viresh Kumar -L: cpufreq@vger.kernel.org L: linux-pm@vger.kernel.org S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git @@ -2426,7 +2425,6 @@ F: include/linux/cpufreq.h CPU FREQUENCY DRIVERS - ARM BIG LITTLE M: Viresh Kumar M: Sudeep Holla -L: cpufreq@vger.kernel.org L: linux-pm@vger.kernel.org W: http://www.arm.com/products/processors/technologies/biglittleprocessing.php S: Maintained diff --git a/drivers/cpufreq/speedstep-centrino.c b/drivers/cpufreq/speedstep-centrino.c index 6723f0390f20..7d4a31571608 100644 --- a/drivers/cpufreq/speedstep-centrino.c +++ b/drivers/cpufreq/speedstep-centrino.c @@ -28,7 +28,7 @@ #include #define PFX "speedstep-centrino: " -#define MAINTAINER "cpufreq@vger.kernel.org" +#define MAINTAINER "linux-pm@vger.kernel.org" #define INTEL_MSR_RANGE (0xffff) diff --git a/tools/power/cpupower/Makefile b/tools/power/cpupower/Makefile index cbfec92af327..3651db7eda23 100644 --- a/tools/power/cpupower/Makefile +++ b/tools/power/cpupower/Makefile @@ -62,7 +62,7 @@ LIB_MAJ= 0.0.0 LIB_MIN= 0 PACKAGE = cpupower -PACKAGE_BUGREPORT = cpufreq@vger.kernel.org +PACKAGE_BUGREPORT = linux-pm@vger.kernel.org LANGUAGES = de fr it cs pt diff --git a/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c b/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c index 0f10b81e3322..5224ee5b392d 100644 --- a/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c +++ b/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c @@ -18,7 +18,7 @@ * 5.) if the third value, "diff_pmtmr", changes between 2. and 4., the * TSC-based delay routine on the Linux kernel does not correctly * handle the cpufreq transition. Please report this to - * cpufreq@vger.kernel.org + * linux-pm@vger.kernel.org */ #include -- cgit v1.2.3 From a0dd7b79657bd6644b914d16ce7f23468c44a7b4 Mon Sep 17 00:00:00 2001 From: Nishanth Menon Date: Mon, 5 May 2014 08:33:50 -0500 Subject: PM / OPP: Move cpufreq specific OPP functions out of generic OPP library CPUFreq specific helper functions for OPP (Operating Performance Points) now use generic OPP functions that allow CPUFreq to be be moved back into CPUFreq framework. This allows for independent modifications or future enhancements as needed isolated to just CPUFreq framework alone. Here, we just move relevant code and documentation to make this part of CPUFreq infrastructure. Cc: Kevin Hilman Signed-off-by: Nishanth Menon Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- Documentation/cpu-freq/core.txt | 29 +++++++++++ Documentation/power/opp.txt | 40 ++------------- drivers/base/power/opp.c | 92 --------------------------------- drivers/cpufreq/Makefile | 2 + drivers/cpufreq/cpufreq_opp.c | 110 ++++++++++++++++++++++++++++++++++++++++ include/linux/cpufreq.h | 21 ++++++++ include/linux/pm_opp.h | 20 -------- 7 files changed, 167 insertions(+), 147 deletions(-) create mode 100644 drivers/cpufreq/cpufreq_opp.c (limited to 'Documentation/cpu-freq') diff --git a/Documentation/cpu-freq/core.txt b/Documentation/cpu-freq/core.txt index 0060d76b445f..70933eadc308 100644 --- a/Documentation/cpu-freq/core.txt +++ b/Documentation/cpu-freq/core.txt @@ -20,6 +20,7 @@ Contents: --------- 1. CPUFreq core and interfaces 2. CPUFreq notifiers +3. CPUFreq Table Generation with Operating Performance Point (OPP) 1. General Information ======================= @@ -92,3 +93,31 @@ values: cpu - number of the affected CPU old - old frequency new - new frequency + +3. CPUFreq Table Generation with Operating Performance Point (OPP) +================================================================== +For details about OPP, see Documentation/power/opp.txt + +dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with + cpufreq_frequency_table_cpuinfo which is provided with the list of + frequencies that are available for operation. This function provides + a ready to use conversion routine to translate the OPP layer's internal + information about the available frequencies into a format readily + providable to cpufreq. + + WARNING: Do not use this function in interrupt context. + + Example: + soc_pm_init() + { + /* Do things */ + r = dev_pm_opp_init_cpufreq_table(dev, &freq_table); + if (!r) + cpufreq_frequency_table_cpuinfo(policy, freq_table); + /* Do other things */ + } + + NOTE: This function is available only if CONFIG_CPU_FREQ is enabled in + addition to CONFIG_PM_OPP. + +dev_pm_opp_free_cpufreq_table - Free up the table allocated by dev_pm_opp_init_cpufreq_table diff --git a/Documentation/power/opp.txt b/Documentation/power/opp.txt index b8a907dc0169..a9adad828cdc 100644 --- a/Documentation/power/opp.txt +++ b/Documentation/power/opp.txt @@ -10,8 +10,7 @@ Contents 3. OPP Search Functions 4. OPP Availability Control Functions 5. OPP Data Retrieval Functions -6. Cpufreq Table Generation -7. Data Structures +6. Data Structures 1. Introduction =============== @@ -72,7 +71,6 @@ operations until that OPP could be re-enabled if possible. OPP library facilitates this concept in it's implementation. The following operational functions operate only on available opps: opp_find_freq_{ceil, floor}, dev_pm_opp_get_voltage, dev_pm_opp_get_freq, dev_pm_opp_get_opp_count -and dev_pm_opp_init_cpufreq_table dev_pm_opp_find_freq_exact is meant to be used to find the opp pointer which can then be used for dev_pm_opp_enable/disable functions to make an opp available as required. @@ -96,10 +94,9 @@ using RCU read locks. The opp_find_freq_{exact,ceil,floor}, opp_get_{voltage, freq, opp_count} fall into this category. opp_{add,enable,disable} are updaters which use mutex and implement it's own -RCU locking mechanisms. dev_pm_opp_init_cpufreq_table acts as an updater and uses -mutex to implment RCU updater strategy. These functions should *NOT* be called -under RCU locks and other contexts that prevent blocking functions in RCU or -mutex operations from working. +RCU locking mechanisms. These functions should *NOT* be called under RCU locks +and other contexts that prevent blocking functions in RCU or mutex operations +from working. 2. Initial OPP List Registration ================================ @@ -311,34 +308,7 @@ dev_pm_opp_get_opp_count - Retrieve the number of available opps for a device /* Do other things */ } -6. Cpufreq Table Generation -=========================== -dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with - cpufreq_frequency_table_cpuinfo which is provided with the list of - frequencies that are available for operation. This function provides - a ready to use conversion routine to translate the OPP layer's internal - information about the available frequencies into a format readily - providable to cpufreq. - - WARNING: Do not use this function in interrupt context. - - Example: - soc_pm_init() - { - /* Do things */ - r = dev_pm_opp_init_cpufreq_table(dev, &freq_table); - if (!r) - cpufreq_frequency_table_cpuinfo(policy, freq_table); - /* Do other things */ - } - - NOTE: This function is available only if CONFIG_CPU_FREQ is enabled in - addition to CONFIG_PM as power management feature is required to - dynamically scale voltage and frequency in a system. - -dev_pm_opp_free_cpufreq_table - Free up the table allocated by dev_pm_opp_init_cpufreq_table - -7. Data Structures +6. Data Structures ================== Typically an SoC contains multiple voltage domains which are variable. Each domain is represented by a device pointer. The relationship to OPP can be diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c index 38b43bb20878..d9e376a6d19d 100644 --- a/drivers/base/power/opp.c +++ b/drivers/base/power/opp.c @@ -15,7 +15,6 @@ #include #include #include -#include #include #include #include @@ -596,97 +595,6 @@ int dev_pm_opp_disable(struct device *dev, unsigned long freq) } EXPORT_SYMBOL_GPL(dev_pm_opp_disable); -#ifdef CONFIG_CPU_FREQ -/** - * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device - * @dev: device for which we do this operation - * @table: Cpufreq table returned back to caller - * - * Generate a cpufreq table for a provided device- this assumes that the - * opp list is already initialized and ready for usage. - * - * This function allocates required memory for the cpufreq table. It is - * expected that the caller does the required maintenance such as freeing - * the table as required. - * - * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM - * if no memory available for the operation (table is not populated), returns 0 - * if successful and table is populated. - * - * WARNING: It is important for the callers to ensure refreshing their copy of - * the table if any of the mentioned functions have been invoked in the interim. - * - * Locking: The internal device_opp and opp structures are RCU protected. - * Since we just use the regular accessor functions to access the internal data - * structures, we use RCU read lock inside this function. As a result, users of - * this function DONOT need to use explicit locks for invoking. - */ -int dev_pm_opp_init_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table) -{ - struct dev_pm_opp *opp; - struct cpufreq_frequency_table *freq_table = NULL; - int i, max_opps, ret = 0; - unsigned long rate; - - rcu_read_lock(); - - max_opps = dev_pm_opp_get_opp_count(dev); - if (max_opps <= 0) { - ret = max_opps ? max_opps : -ENODATA; - goto out; - } - - freq_table = kzalloc(sizeof(*freq_table) * (max_opps + 1), GFP_KERNEL); - if (!freq_table) { - ret = -ENOMEM; - goto out; - } - - for (i = 0, rate = 0; i < max_opps; i++, rate++) { - /* find next rate */ - opp = dev_pm_opp_find_freq_ceil(dev, &rate); - if (IS_ERR(opp)) { - ret = PTR_ERR(opp); - goto out; - } - freq_table[i].driver_data = i; - freq_table[i].frequency = rate / 1000; - } - - freq_table[i].driver_data = i; - freq_table[i].frequency = CPUFREQ_TABLE_END; - - *table = &freq_table[0]; - -out: - rcu_read_unlock(); - if (ret) - kfree(freq_table); - - return ret; -} -EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table); - -/** - * dev_pm_opp_free_cpufreq_table() - free the cpufreq table - * @dev: device for which we do this operation - * @table: table to free - * - * Free up the table allocated by dev_pm_opp_init_cpufreq_table - */ -void dev_pm_opp_free_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table) -{ - if (!table) - return; - - kfree(*table); - *table = NULL; -} -EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table); -#endif /* CONFIG_CPU_FREQ */ - /** * dev_pm_opp_get_notifier() - find notifier_head of the device with opp * @dev: device pointer used to lookup device OPPs. diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 0dbb963c1aef..738c8b7b17dc 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -1,5 +1,7 @@ # CPUfreq core obj-$(CONFIG_CPU_FREQ) += cpufreq.o freq_table.o +obj-$(CONFIG_PM_OPP) += cpufreq_opp.o + # CPUfreq stats obj-$(CONFIG_CPU_FREQ_STAT) += cpufreq_stats.o diff --git a/drivers/cpufreq/cpufreq_opp.c b/drivers/cpufreq/cpufreq_opp.c new file mode 100644 index 000000000000..c0c6f4a4eccf --- /dev/null +++ b/drivers/cpufreq/cpufreq_opp.c @@ -0,0 +1,110 @@ +/* + * Generic OPP helper interface for CPUFreq drivers + * + * Copyright (C) 2009-2014 Texas Instruments Incorporated. + * Nishanth Menon + * Romit Dasgupta + * Kevin Hilman + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +/** + * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device + * @dev: device for which we do this operation + * @table: Cpufreq table returned back to caller + * + * Generate a cpufreq table for a provided device- this assumes that the + * opp list is already initialized and ready for usage. + * + * This function allocates required memory for the cpufreq table. It is + * expected that the caller does the required maintenance such as freeing + * the table as required. + * + * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM + * if no memory available for the operation (table is not populated), returns 0 + * if successful and table is populated. + * + * WARNING: It is important for the callers to ensure refreshing their copy of + * the table if any of the mentioned functions have been invoked in the interim. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Since we just use the regular accessor functions to access the internal data + * structures, we use RCU read lock inside this function. As a result, users of + * this function DONOT need to use explicit locks for invoking. + */ +int dev_pm_opp_init_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table **table) +{ + struct dev_pm_opp *opp; + struct cpufreq_frequency_table *freq_table = NULL; + int i, max_opps, ret = 0; + unsigned long rate; + + rcu_read_lock(); + + max_opps = dev_pm_opp_get_opp_count(dev); + if (max_opps <= 0) { + ret = max_opps ? max_opps : -ENODATA; + goto out; + } + + freq_table = kzalloc(sizeof(*freq_table) * (max_opps + 1), GFP_KERNEL); + if (!freq_table) { + ret = -ENOMEM; + goto out; + } + + for (i = 0, rate = 0; i < max_opps; i++, rate++) { + /* find next rate */ + opp = dev_pm_opp_find_freq_ceil(dev, &rate); + if (IS_ERR(opp)) { + ret = PTR_ERR(opp); + goto out; + } + freq_table[i].driver_data = i; + freq_table[i].frequency = rate / 1000; + } + + freq_table[i].driver_data = i; + freq_table[i].frequency = CPUFREQ_TABLE_END; + + *table = &freq_table[0]; + +out: + rcu_read_unlock(); + if (ret) + kfree(freq_table); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table); + +/** + * dev_pm_opp_free_cpufreq_table() - free the cpufreq table + * @dev: device for which we do this operation + * @table: table to free + * + * Free up the table allocated by dev_pm_opp_init_cpufreq_table + */ +void dev_pm_opp_free_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table **table) +{ + if (!table) + return; + + kfree(*table); + *table = NULL; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table); diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index f3822f836e14..9d803b529ac2 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -469,6 +469,27 @@ struct cpufreq_frequency_table { * order */ }; +#if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) +int dev_pm_opp_init_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table **table); +void dev_pm_opp_free_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table **table); +#else +static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table + **table) +{ + return -EINVAL; +} + +static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, + struct cpufreq_frequency_table + **table) +{ +} +#endif + + bool cpufreq_next_valid(struct cpufreq_frequency_table **pos); /* diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 5151b0059585..0330217abfad 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -15,7 +15,6 @@ #define __LINUX_OPP_H__ #include -#include #include struct dev_pm_opp; @@ -117,23 +116,4 @@ static inline int of_init_opp_table(struct device *dev) } #endif -#if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) -int dev_pm_opp_init_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table); -void dev_pm_opp_free_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table); -#else -static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table) -{ - return -EINVAL; -} - -static inline -void dev_pm_opp_free_cpufreq_table(struct device *dev, - struct cpufreq_frequency_table **table) -{ -} -#endif /* CONFIG_CPU_FREQ */ - #endif /* __LINUX_OPP_H__ */ -- cgit v1.2.3