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path: root/drivers/cpufreq/cpufreq-cpu0.c
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2013-06-05cpufreq: cpufreq-cpu0: use the exact frequency for clk_set_rate()Guennadi Liakhovetski1-2/+3
clk_set_rate() isn't supposed to accept approximate frequencies, instead a supported frequency should be obtained from clk_round_rate() and then used to set the clock. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Acked-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-12cpufreq: cpufreq-cpu0: Free parent node for error casesViresh Kumar1-1/+4
We are freeing parent node in success cases but not in failure cases. Let's do it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-12cpufreq: cpufreq-cpu0: defer probe when regulator is not readyNishanth Menon1-6/+16
With commit 1e4b545, regulator_get will now return -EPROBE_DEFER when the cpu0-supply node is present, but the regulator is not yet registered. It is possible for this to occur when the regulator registration by itself might be defered due to some dependent interface not yet instantiated. For example: an regulator which uses I2C and GPIO might need both systems available before proceeding, in this case, the regulator might defer it's registration. However, the cpufreq-cpu0 driver assumes that any un-successful return result is equivalent of failure. When the regulator_get returns failure other than -EPROBE_DEFER, it makes sense to assume that supply node is not present and proceed with the assumption that only clock control is necessary in the platform. With this change, we can now handle the following conditions: a) cpu0-supply binding is not present, regulator_get will return appropriate error result, resulting in cpufreq-cpu0 driver controlling just the clock. b) cpu0-supply binding is present, regulator_get returns -EPROBE_DEFER, we retry resulting in cpufreq-cpu0 driver registering later once the regulator is available. c) cpu0-supply binding is present, regulator_get returns -EPROBE_DEFER, however, regulator never registers, we retry until cpufreq-cpu0 driver fails to register pointing at device tree information bug. However, in this case, the fact that cpufreq-cpu0 operates with clock only when the DT binding clearly indicates need of a supply is a bug of it's own. d) cpu0-supply gets an regulator at probe - cpufreq-cpu0 driver controls both the clock and regulator Signed-off-by: Nishanth Menon <nm@ti.com> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-28Merge branch 'pm-cpufreq'Rafael J. Wysocki1-18/+14
* pm-cpufreq: (57 commits) cpufreq: MAINTAINERS: Add co-maintainer cpufreq: pxa2xx: initialize variables ARM: S5pv210: compiling issue, ARM_S5PV210_CPUFREQ needs CONFIG_CPU_FREQ_TABLE=y cpufreq: cpu0: Put cpu parent node after using it cpufreq: ARM big LITTLE: Adapt to latest cpufreq updates cpufreq: ARM big LITTLE: put DT nodes after using them cpufreq: Don't call __cpufreq_governor() for drivers without target() cpufreq: exynos5440: Protect OPP search calls with RCU lock cpufreq: dbx500: Round to closest available freq cpufreq: Call __cpufreq_governor() with correct policy->cpus mask cpufreq / intel_pstate: Optimize intel_pstate_set_policy cpufreq: OMAP: instantiate omap-cpufreq as a platform_driver arm: exynos: Enable OPP library support for exynos5440 cpufreq: exynos: Remove error return even if no soc is found cpufreq: exynos: Add cpufreq driver for exynos5440 cpufreq: AMD "frequency sensitivity feedback" powersave bias for ondemand governor cpufreq: ondemand: allow custom powersave_bias_target handler to be registered cpufreq: convert cpufreq_driver to using RCU cpufreq: powerpc/platforms/cell: move cpufreq driver to drivers/cpufreq cpufreq: sparc: move cpufreq driver to drivers/cpufreq ... Conflicts: MAINTAINERS (with commit a8e39c3 from pm-cpuidle) drivers/cpufreq/cpufreq_governor.h (with commit beb0ff3)
2013-04-22cpufreq: cpu0: Put cpu parent node after using itViresh Kumar1-0/+1
Parent node must be put after using it to balance its usage count. This was missing in cpufreq-cpu0 driver. Fix it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02cpufreq: Notify all policy->cpus in cpufreq_notify_transition()Viresh Kumar1-9/+3
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>
2013-04-02cpufreq: cpufreq-cpu0: Call CPUFREQ_POSTCHANGE notifier for failure cases tooViresh Kumar1-5/+8
Currently we are simply returning from target() if we encounter some error after broadcasting CPUFREQ_PRECHANGE notifier. Which looks to be wrong as others might depend on POSTCHANGE notifier for their functioning. So, better broadcast CPUFREQ_POSTCHANGE notifier for these failure cases too, but with old frequency. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02cpufreq: cpufreq-cpu0: No need to check cpu number in init()Viresh Kumar1-3/+0
It is not possible for init() to be called for any cpu other than cpu0. During bootup whatever cpu is used to boot system will be assigned as cpu0. And later on policy->cpu can only change if we hotunplug all cpus first and then hotplug them back in different order, which isn't possible (system requires atleast one cpu to be up always :)). Though I can see one situation where policy->cpu can be different then zero. - Hot-unplug cpu 0. - rmmod cpufreq-cpu0 module - insmod it back - hotplug cpu 0 again. Here, policy->cpu would be different. But the driver doesn't have any dependency on cpu0 as such. We don't mind which cpu of a system is policy->cpu and so this check is just not required. Remove it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02cpufreq: check OF node /cpus presence before dereferencing itPaolo Pisati1-2/+8
Check for the presence of the '/cpus' OF node before dereferencing it blindly: [ 4.181793] Unable to handle kernel NULL pointer dereference at virtual address 0000001c [ 4.181793] pgd = c0004000 [ 4.181823] [0000001c] *pgd=00000000 [ 4.181823] Internal error: Oops: 5 [#1] SMP ARM [ 4.181823] Modules linked in: [ 4.181823] CPU: 1 Tainted: G W (3.8.0-15-generic #25~hbankD) [ 4.181854] PC is at of_get_next_child+0x64/0x70 [ 4.181854] LR is at of_get_next_child+0x24/0x70 [ 4.181854] pc : [<c04fda18>] lr : [<c04fd9d8>] psr: 60000113 [ 4.181854] sp : ed891ec0 ip : ed891ec0 fp : ed891ed4 [ 4.181884] r10: c04dafd0 r9 : c098690c r8 : c0936208 [ 4.181884] r7 : ed890000 r6 : c0a63d00 r5 : 00000000 r4 : 00000000 [ 4.181884] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : c0b2acc8 [ 4.181884] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 4.181884] Control: 10c5387d Table: adcb804a DAC: 00000015 [ 4.181915] Process swapper/0 (pid: 1, stack limit = 0xed890238) [ 4.181915] Stack: (0xed891ec0 to 0xed892000) [ 4.181915] 1ec0: c09b7b70 00000007 ed891efc ed891ed8 c04daff4 c04fd9c0 00000000 c09b7b70 [ 4.181915] 1ee0: 00000007 c0a63d00 ed890000 c0936208 ed891f54 ed891f00 c00088e0 c04dafdc [ 4.181945] 1f00: ed891f54 ed891f10 c006e940 00000000 00000000 00000007 00000007 c08a4914 [ 4.181945] 1f20: 00000000 c07dbd30 c0a63d00 c09b7b70 00000007 c0a63d00 000000bc c0936208 [ 4.181945] 1f40: c098690c c0986914 ed891f94 ed891f58 c0936a40 c00087bc 00000007 00000007 [ 4.181976] 1f60: c0936208 be8bda20 b6eea010 c0a63d00 c064547c 00000000 00000000 00000000 [ 4.181976] 1f80: 00000000 00000000 ed891fac ed891f98 c0645498 c09368c8 00000000 00000000 [ 4.181976] 1fa0: 00000000 ed891fb0 c0014658 c0645488 00000000 00000000 00000000 00000000 [ 4.182006] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 4.182006] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [ 4.182037] [<c04fda18>] (of_get_next_child+0x64/0x70) from [<c04daff4>] (cpu0_cpufreq_driver_init+0x24/0x284) [ 4.182067] [<c04daff4>] (cpu0_cpufreq_driver_init+0x24/0x284) from [<c00088e0>] (do_one_initcall+0x130/0x1b0) [ 4.182067] [<c00088e0>] (do_one_initcall+0x130/0x1b0) from [<c0936a40>] (kernel_init_freeable+0x184/0x24c) [ 4.182098] [<c0936a40>] (kernel_init_freeable+0x184/0x24c) from [<c0645498>] (kernel_init+0x1c/0xf4) [ 4.182128] [<c0645498>] (kernel_init+0x1c/0xf4) from [<c0014658>] (ret_from_fork+0x14/0x20) [ 4.182128] Code: f57ff04f e320f004 e89da830 e89da830 (e595001c) [ 4.182128] ---[ end trace 634903a22e8609cb ]--- [ 4.182189] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 4.182189] [ 4.642395] CPU0: stopping [rjw: Changelog] Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-01cpufreq: Fix unsigned variable being checked for negative valuejhbird.choi@samsung.com1-1/+2
clk_round_rate() returns singed value which was assigned to an unsigned variable. So it can't be checked for negative. Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com> Acked-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: Remove unnecessary use of policy->shared_typeViresh Kumar1-1/+0
policy->shared_type field was added only for SoCs with ACPI support: commit 3b2d99429e3386b6e2ac949fc72486509c8bbe36 Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Date: Wed Dec 14 15:05:00 2005 -0500 P-state software coordination for ACPI core http://bugzilla.kernel.org/show_bug.cgi?id=5737 Many non-ACPI systems are filling this field by mistake, which makes its usage confusing. Lets clean it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq: instantiate cpufreq-cpu0 as a platform_driverShawn Guo1-12/+23
As multiplatform build is being adopted by more and more ARM platforms, initcall function should be used very carefully. For example, when GENERIC_CPUFREQ_CPU0 is built in the kernel, cpu0_cpufreq_driver_init() will be called on all the platforms to initialize cpufreq-cpu0 driver. To eliminate this undesired the effect, the patch changes cpufreq-cpu0 driver to have it instantiated as a platform_driver. Then it will only run on platforms that create the platform_device "cpufreq-cpu0". Along with the change, it also changes cpu_dev to be &pdev->dev, so that managed functions can start working, and module build gets supported too. The highbank-cpufreq driver is also updated accordingly to adapt the changes on cpufreq-cpu0. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Mark Langsdorf <mark.langsdorf@calxeda.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-02cpufreq / highbank: add support for highbank cpufreqMark Langsdorf1-1/+5
Highbank processors depend on the external ECME to perform voltage management based on a requested frequency. Communication between the A9 cores and the ECME happens over the pl320 IPC channel. Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com> Reviewed-by: Shawn Guo <shawn.guo@linaro.org> Reviewed-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-22cpufreq: cpufreq-cpu0: use RCU locks around usage of OPPNishanth Menon1-0/+5
OPP pointer is RCU protected, hence after finding it, de-reference also should be protected with the same RCU context else the OPP pointer may become invalid. Reported-by: Jack Mitchell <jack@embed.me.uk> Tested-by: Alexander Holler <holler@ahsoftware.de> Tested-by: Jack Mitchell <jack@embed.me.uk> Acked-by: Alexander Holler <holler@ahsoftware.de> Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-21cpufreq: remove use of __devinitBill Pemberton1-1/+1
CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-09-10cpufreq: Add a generic cpufreq-cpu0 driverShawn Guo1-0/+269
It adds a generic cpufreq driver for CPU0 frequency management based on clk, regulator, OPP and device tree support. It can support both uniprocessor (UP) and those symmetric multiprocessor (SMP) systems which share clock and voltage across all CPUs. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: AnilKumar Ch <anilkumar@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>