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  1. 15 Sep, 2015 1 commit
  3. 01 Sep, 2015 1 commit
    • Pi-Cheng Chen's avatar
      cpufreq: mediatek: Add MT8173 cpufreq driver · 1453863f
      Pi-Cheng Chen authored 
      Mediatek MT8173 is an ARMv8 based quad-core (2*Cortex-A53 and
2*Cortex-A72) SoC with duall clusters. For each cluster, two voltage
inputs, Vproc and Vsram are supplied by two regulators. For the big
cluster, two regulators come from different PMICs. In this case, when
scaling voltage inputs of the cluster, the voltages of two regulator
inputs need to be controlled by software explicitly under the SoC
specific limitation:

	100mV < Vsram - Vproc < 200mV

which is called 'voltage tracking' mechanism. And when scaling the
frequency of cluster clock input, the input MUX need to be parented to
another "intermediate" stable PLL first and reparented to the original
PLL once the original PLL is stable at the target frequency. This patch
implements those mechanisms to enable CPU DVFS support for Mediatek
MT8173 SoC.
Signed-off-by: default avatarPi-Cheng Chen <pi-cheng.chen@linaro.org>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      1453863f
  5. 13 Aug, 2015 2 commits
  7. 24 Jul, 2015 1 commit
  9. 16 Jul, 2015 2 commits
  11. 20 Jun, 2015 1 commit
  13. 02 Apr, 2015 1 commit
  15. 18 Mar, 2015 1 commit
  17. 31 Jan, 2015 1 commit
    • Arnd Bergmann's avatar
      cpufreq: exynos: allow modular build · 8b2b4a4e
      Arnd Bergmann authored 
      The exynos cpufreq driver code recently gained a dependency on the
cooling code, which may be a loadable module. This breaks an ARM
allmodconfig build:

drivers/built-in.o: In function `exynos_cpufreq_probe':
:(.text+0x1748e8): undefined reference to `of_cpufreq_cooling_register'

To avoid this problem, change cpufreq Kconfig to allow the drivers
to be loadable modules as well and enforce a dependency on the
thermal module.

This change, in order to allow module builds on this cpufreq
driver, properly constructs the driver into a single module,
instead of several modules. The change also keeps the proper
platform dependency, and therefore, it wont load in platforms
that are not supposed to be loaded. The user will be able to
build the support for all platforms, or select which platforms
(s)he wants (as originally), except that now it can be a module,
instead.

Besides, it will still keep the driver only on those configs
that expect it to be on. And it won't compile/load on platforms
that it is not supposed to. It brings the config ARM_EXYNOS_CPU_FREQ_BOOST_SW
closer to this driver, so it looks better in the menuconfig.

We intentionally change ARM_EXYNOS5440_CPUFREQ to be tristate too, to
avoid future troubles.

Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-pm@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Fixes: e725d26c ("cpufreq: exynos: Use device tree to determine if cpufreq cooling should be registered")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarEduardo Valentin <edubezval@gmail.com>
      8b2b4a4e
  19. 20 Dec, 2014 1 commit
  21. 27 Nov, 2014 1 commit
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  25. 03 Oct, 2014 1 commit
  27. 09 Jul, 2014 1 commit
  29. 06 May, 2014 1 commit
  31. 07 Apr, 2014 1 commit
    • Vaidyanathan Srinivasan's avatar
      cpufreq: powernv: cpufreq driver for powernv platform · b3d627a5
      Vaidyanathan Srinivasan authored 
      Backend driver to dynamically set voltage and frequency on
IBM POWER non-virtualized platforms.  Power management SPRs
are used to set the required PState.

This driver works in conjunction with cpufreq governors
like 'ondemand' to provide a demand based frequency and
voltage setting on IBM POWER non-virtualized platforms.

PState table is obtained from OPAL v3 firmware through device
tree.

powernv_cpufreq back-end driver would parse the relevant device-tree
nodes and initialise the cpufreq subsystem on powernv platform.

The code was originally written by svaidy@linux.vnet.ibm.com. Over
time it was modified to accomodate bug-fixes as well as updates to the
the cpu-freq core. Relevant portions of the change logs corresponding
to those modifications are noted below:

 * The policy->cpus needs to be populated in a hotplug-invariant
   manner instead of using cpu_sibling_mask() which varies with
   cpu-hotplug. This is because the cpufreq core code copies this
   content into policy->related_cpus mask which should not vary on
   cpu-hotplug. [Authored by srivatsa.bhat@linux.vnet.ibm.com]

 * Create a helper routine that can return the cpu-frequency for the
   corresponding pstate_id. Also, cache the values of the pstate_max,
   pstate_min and pstate_nominal and nr_pstates in a static structure
   so that they can be reused in the future to perform any
   validations. [Authored by ego@linux.vnet.ibm.com]

 * Create a driver attribute named cpuinfo_nominal_freq which creates
   a sysfs read-only file named cpuinfo_nominal_freq. Export the
   frequency corresponding to the nominal_pstate through this
   interface.

     Nominal frequency is the highest non-turbo frequency for the
   platform.  This is generally used for setting governor policies
   from user space for optimal energy efficiency. [Authored by
   ego@linux.vnet.ibm.com]

 * Implement a powernv_cpufreq_get(unsigned int cpu) method which will
   return the current operating frequency. Export this via the sysfs
   interface cpuinfo_cur_freq by setting powernv_cpufreq_driver.get to
   powernv_cpufreq_get(). [Authored by ego@linux.vnet.ibm.com]

[Change log updated by ego@linux.vnet.ibm.com]
Reviewed-by: default avatarPreeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: default avatarVaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: default avatarSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarGautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      b3d627a5
  33. 29 Oct, 2013 1 commit
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  47. 10 Apr, 2013 12 commits
  49. 08 Apr, 2013 2 commits
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