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* cpufreq: send new set of notification for transition failuresViresh Kumar2014-01-061-11/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the current code, if we fail during a frequency transition, we simply send the POSTCHANGE notification with the old frequency. This isn't enough. One of the core users of these notifications is the code responsible for keeping loops_per_jiffy aligned with frequency changes. And mostly it is written as: if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) { update-loops-per-jiffy... } So, suppose we are changing to a higher frequency and failed during transition, then following will happen: - CPUFREQ_PRECHANGE notification with freq-new > freq-old - CPUFREQ_POSTCHANGE notification with freq-new == freq-old The first one will update loops_per_jiffy and second one will do nothing. Even if we send the 2nd notification by exchanging values of freq-new and old, some users of these notifications might get unstable. This can be fixed by simply calling cpufreq_notify_post_transition() with error code and this routine will take care of sending notifications in the correct order. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [rjw: Folded 3 patches into one, rebased unicore2 changes] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Merge branch 'pm-cpufreq'Rafael J. Wysocki2013-10-281-9/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq: (167 commits) cpufreq: create per policy rwsem instead of per CPU cpu_policy_rwsem intel_pstate: Add Baytrail support intel_pstate: Refactor driver to support CPUs with different MSR layouts cpufreq: Implement light weight ->target_index() routine PM / OPP: rename header to linux/pm_opp.h PM / OPP: rename data structures to dev_pm equivalents PM / OPP: rename functions to dev_pm_opp* cpufreq / governor: Remove fossil comment cpufreq: exynos4210: Use the common clock framework to set APLL clock rate cpufreq: exynos4x12: Use the common clock framework to set APLL clock rate cpufreq: Detect spurious invocations of update_policy_cpu() cpufreq: pmac64: enable cpufreq on iMac G5 (iSight) model cpufreq: pmac64: provide cpufreq transition latency for older G5 models cpufreq: pmac64: speed up frequency switch cpufreq: highbank-cpufreq: Enable Midway/ECX-2000 exynos-cpufreq: fix false return check from "regulator_set_voltage" speedstep-centrino: Remove unnecessary braces acpi-cpufreq: Add comment under ACPI_ADR_SPACE_SYSTEM_IO case cpufreq: arm-big-little: use clk_get instead of clk_get_sys cpufreq: exynos: Show a list of available frequencies ... Conflicts: drivers/devfreq/exynos/exynos5_bus.c
| * cpufreq: pcc: don't initialize part of policy set by coreViresh Kumar2013-10-161-7/+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: add new routine cpufreq_verify_within_cpu_limits()Viresh Kumar2013-10-161-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Most of the users of cpufreq_verify_within_limits() calls it for limiting with min/max from policy->cpuinfo. We can make that code simple by introducing another routine which will do this for them automatically. This patch adds another routine cpufreq_verify_within_cpu_limits() and updates others to use it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | pcc_freq: convert acpi_get_handle() to acpi_has_method()Zhang Rui2013-09-241-3/+2
|/ | | | | | | | | | | | | | | | acpi_has_method() is a new ACPI API introduced to check the existence of an ACPI control method. It can be used to replace acpi_get_handle() in the case that 1. the calling function doesn't need the ACPI handle of the control method. and 2. the calling function doesn't care the reason why the method is unavailable. Convert acpi_get_handle() to acpi_has_method() in drivers/cpufreq/pcc_freq.c in this patch. Signed-off-by: Zhang Rui <rui.zhang@intel.com> 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: pcc: call CPUFREQ_POSTCHANGE notfier in error casesViresh Kumar2013-06-241-0/+2
| | | | | | | | | | | | | | PRECHANGE and POSTCHANGE notifiers must be called in groups, i.e either both should be called or both shouldn't be. In case we have started PRECHANGE notifier and found an error, we must call POSTCHANGE notifier with freqs.new = freqs.old to guarantee that the sequence of calling notifiers is complete. This patch fixes it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* cpufreq: Notify all policy->cpus in cpufreq_notify_transition()Viresh Kumar2013-04-021-3/+2
| | | | | | | | | | | | | | | | 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>
* drivers/cpufreq/pcc-cpufreq.c: fix error return codeJulia Lawall2012-08-081-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert a 0 error return code to a negative one, as returned elsewhere in the function. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ identifier ret; expression e,e1,e2,e3,e4,x; @@ ( if (\(ret != 0\|ret < 0\) || ...) { ... return ...; } | ret = 0 ) ... when != ret = e1 *x = \(kmalloc\|kzalloc\|kcalloc\|devm_kzalloc\|ioremap\|ioremap_nocache\|devm_ioremap\|devm_ioremap_nocache\)(...); ... when != x = e2 when != ret = e3 *if (x == NULL || ...) { ... when != ret = e4 * return ret; } // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* drivers/cpufreq/pcc-cpufreq.c: avoid NULL pointer dereferenceNaga Chumbalkar2011-09-141-0/+3
| | | | | | | | | | | | | | | | | per_cpu(processors, n) can be NULL, resulting in: Loading CPUFreq modules[ 437.661360] BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffffa0434314>] pcc_cpufreq_cpu_init+0x74/0x220 [pcc_cpufreq] It's better to avoid the oops by failing the driver, and allowing the system to boot. Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Len Brown <lenb@kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [CPUFREQ] Move x86 drivers to drivers/cpufreq/Dave Jones2011-05-191-0/+621
Signed-off-by: Dave Jones <davej@redhat.com>
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