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* powernow-k6: reorder frequenciesMikulas Patocka2014-01-061-7/+10
| | | | | | | | | This patch reorders reported frequencies from the highest to the lowest, just like in other frequency drivers. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* powernow-k6: correctly initialize default parametersMikulas Patocka2014-01-061-4/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The powernow-k6 driver used to read the initial multiplier from the powernow register. However, there is a problem with this: * If there was a frequency transition before, the multiplier read from the register corresponds to the current multiplier. * If there was no frequency transition since reset, the field in the register always reads as zero, regardless of the current multiplier that is set using switches on the mainboard and that the CPU is running at. The zero value corresponds to multiplier 4.5, so as a consequence, the powernow-k6 driver always assumes multiplier 4.5. For example, if we have 550MHz CPU with bus frequency 100MHz and multiplier 5.5, the powernow-k6 driver thinks that the multiplier is 4.5 and bus frequency is 122MHz. The powernow-k6 driver then sets the multiplier to 4.5, underclocking the CPU to 450MHz, but reports the current frequency as 550MHz. There is no reliable way how to read the initial multiplier. I modified the driver so that it contains a table of known frequencies (based on parameters of existing CPUs and some common overclocking schemes) and sets the multiplier according to the frequency. If the frequency is unknown (because of unusual overclocking or underclocking), the user must supply the bus speed and maximum multiplier as module parameters. This patch should be backported to all stable kernels. If it doesn't apply cleanly, change it, or ask me to change it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* powernow-k6: disable cache when changing frequencyMikulas Patocka2014-01-061-17/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I found out that a system with k6-3+ processor is unstable during network server load. The system locks up or the network card stops receiving. The reason for the instability is the CPU frequency scaling. During frequency transition the processor is in "EPM Stop Grant" state. The documentation says that the processor doesn't respond to inquiry requests in this state. Consequently, coherency of processor caches and bus master devices is not maintained, causing the system instability. This patch flushes the cache during frequency transition. It fixes the instability. Other minor changes: * u64 invalue changed to unsigned long because the variable is 32-bit * move the logic to set the multiplier to a separate function powernow_k6_set_cpu_multiplier * preserve lower 5 bits of the powernow port instead of 4 (the voltage field has 5 bits) * mask interrupts when reading the multiplier, so that the port is not open during other activity (running other kernel code with the port open shouldn't cause any misbehavior, but we should better be safe and keep the port closed) This patch should be backported to all stable kernels. If it doesn't apply cleanly, change it, or ask me to change it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Implement light weight ->target_index() routineViresh Kumar2013-10-251-30/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
* cpufreq: powernow: don't initialize part of policy set by coreViresh Kumar2013-10-161-1/+0
| | | | | | | | | | | Many common initializations of struct policy are moved to core now and hence this driver doesn't need to do it. This patch removes such code. Most recent of those changes is to call ->get() in the core after calling ->init(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: powernow: Use generic cpufreq routinesViresh Kumar2013-10-161-20/+2
| | | | | | | | | | | Most of the CPUFreq drivers do similar things in .exit() and .verify() routines and .attr. So its better if we have generic routines for them which can be used by cpufreq drivers then. This patch uses these generic routines in the powernow driver. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: powernow: use cpufreq_table_validate_and_show()Viresh Kumar2013-09-301-8/+1
| | | | | | | | Lets use cpufreq_table_validate_and_show() instead of calling cpufreq_frequency_table_cpuinfo() and cpufreq_frequency_table_get_attr(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Drop the owner field from struct cpufreq_driverViresh Kumar2013-08-101-1/+0
| | | | | | | | | | We don't need to set .owner = THIS_MODULE any more in cpufreq drivers as this field isn't used any more by the cpufreq core. This patch removes it and updates all dependent drivers accordingly. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: rename index as driver_data in cpufreq_frequency_tableViresh Kumar2013-06-041-4/+4
| | | | | | | | | | | | | | | | | The "index" field of struct cpufreq_frequency_table was never an index and isn't used at all by the cpufreq core. It only is useful for cpufreq drivers for their internal purposes. Many people nowadays blindly set it in ascending order with the assumption that the core will use it, which is a mistake. Rename it to "driver_data" as that's what its purpose is. All of its users are updated accordingly. [rjw: Changelog] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Notify all policy->cpus in cpufreq_notify_transition()Viresh Kumar2013-04-021-6/+6
| | | | | | | | | | | | | | | | policy->cpus contains all online cpus that have single shared clock line. And their frequencies are always updated together. Many SMP system's cpufreq drivers take care of this in individual drivers but the best place for this code is in cpufreq core. This patch modifies cpufreq_notify_transition() to notify frequency change for all cpus in policy->cpus and hence updates all users of this API. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* powernow-k6: Really enable auto-loadingBen Hutchings2012-02-131-1/+1
| | | | | | | | | | | Commit fa8031aefec0cf7ea6c2387c93610d99d9659aa2 ('cpufreq: Add support for x86 cpuinfo auto loading v4') added a device ID table to this driver, but didn't declare it as the module device ID table. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Acked-by: Thomas Renninger <trenn@suse.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cpufreq: Add support for x86 cpuinfo auto loading v4Andi Kleen2012-01-261-4/+8
| | | | | | | | | | | | | | | | | | | | | | | | This marks all the x86 cpuinfo tables to the CPU specific device drivers, to allow auto loading by udev. This should simplify the distribution startup scripts for this greatly. I didn't add MODULE_DEVICE_IDs to the centrino and p4-clockmod drivers, because those probably shouldn't be auto loaded and the acpi driver be used instead (not fully sure on that, would appreciate feedback) The old nforce drivers autoload based on the PCI ID. ACPI cpufreq is autoloaded in another patch. v3: Autoload gx based on PCI IDs only. Remove cpu check (Dave Jones) v4: Use newly introduce HW_PSTATE feature for powernow-k8 loading Cc: Dave Jones <davej@redhat.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Thomas Renninger <trenn@suse.de> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [CPUFREQ] Move x86 drivers to drivers/cpufreq/Dave Jones2011-05-191-0/+261
Signed-off-by: Dave Jones <davej@redhat.com>
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