Merge branch 'pm-cpufreq'

total 0

drwxr-xr-x  2 root root    0 May 14 16:06 .

drwxr-xr-x  3 root root    0 May 14 15:58 ..

--w-------  1 root root 4096 May 14 16:06 reset

-r--r--r--  1 root root 4096 May 14 16:06 time_in_state

-r--r--r--  1 root root 4096 May 14 16:06 total_trans

-r--r--r--  1 root root 4096 May 14 16:06 trans_table

--------------------------------------------------------------------------------

-  reset

Write-only attribute that can be used to reset the stat counters. This can be

useful for evaluating system behaviour under different governors without the

need for a reboot.

-  time_in_state

This gives the amount of time spent in each of the frequencies supported by

this CPU. The cat output will have "<frequency> <time>" pair in each line, which

core, the driver provides its own sysfs files to control the P-State selection.

These files have been added to /sys/devices/system/cpu/intel_pstate/.

Any changes made to these files are applicable to all CPUs (even in a

multi-package system).

multi-package system, Refer to later section on placing "Per-CPU limits").

      max_perf_pct: Limits the maximum P-State that will be requested by

      the driver. It states it as a percentage of the available performance. The

driver selects a single P-State, the actual frequency the processor

will run at is selected by the processor itself.

Per-CPU limits

The kernel command line option "intel_pstate=per_cpu_perf_limits" forces

the intel_pstate driver to use per-CPU performance limits.  When it is set,

the sysfs control interface described above is subject to limitations.

- The following controls are not available for both read and write

	/sys/devices/system/cpu/intel_pstate/max_perf_pct

	/sys/devices/system/cpu/intel_pstate/min_perf_pct

- The following controls can be used to set performance limits, as far as the

architecture of the processor permits:

	/sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq

	/sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq

	/sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

- User can still observe turbo percent and number of P-States from

	/sys/devices/system/cpu/intel_pstate/turbo_pct

	/sys/devices/system/cpu/intel_pstate/num_pstates

- User can read write system wide turbo status

	/sys/devices/system/cpu/no_turbo

Support of energy performance hints

It is possible to provide hints to the HWP algorithms in the processor

to be more performance centric to more energy centric. When the driver

is using HWP, two additional cpufreq sysfs attributes are presented for

each logical CPU.

These attributes are:

	- energy_performance_available_preferences

	- energy_performance_preference

To get list of supported hints:

$ cat energy_performance_available_preferences

    default performance balance_performance balance_power power

The current preference can be read or changed via cpufreq sysfs

attribute "energy_performance_preference". Reading from this attribute

will display current effective setting. User can write any of the valid

preference string to this attribute. User can always restore to power-on

default by writing "default".

Since threads can migrate to different CPUs, this is possible that the

new CPU may have different energy performance preference than the previous

one. To avoid such issues, either threads can be pinned to specific CPUs

or set the same energy performance preference value to all CPUs.

Tuning Intel P-State driver

When HWP mode is not used, debugfs files have also been added to allow the

tuning of the internal governor algorithm. These files are located at

/sys/kernel/debug/pstate_snb/. The algorithm uses a PID (Proportional

Integral Derivative) controller. The PID tunable parameters are:

When the performance can be tuned using PID (Proportional Integral

Derivative) controller, debugfs files are provided for adjusting performance.

They are presented under:

/sys/kernel/debug/pstate_snb/

The PID tunable parameters are:

      deadband

      d_gain_pct

      i_gain_pct

Broadcom AVS mail box and interrupt register bindings

=====================================================

A total of three DT nodes are required. One node (brcm,avs-cpu-data-mem)

references the mailbox register used to communicate with the AVS CPU[1]. The

second node (brcm,avs-cpu-l2-intr) is required to trigger an interrupt on

the AVS CPU. The interrupt tells the AVS CPU that it needs to process a

command sent to it by a driver. Interrupting the AVS CPU is mandatory for

commands to be processed.

The interface also requires a reference to the AVS host interrupt controller,

so a driver can react to interrupts generated by the AVS CPU whenever a command

has been processed. See [2] for more information on the brcm,l2-intc node.

[1] The AVS CPU is an independent co-processor that runs proprietary

firmware. On some SoCs, this firmware supports DFS and DVFS in addition to

Adaptive Voltage Scaling.

[2] Documentation/devicetree/bindings/interrupt-controller/brcm,l2-intc.txt

Node brcm,avs-cpu-data-mem

--------------------------

Required properties:

- compatible: must include: brcm,avs-cpu-data-mem and

              should include: one of brcm,bcm7271-avs-cpu-data-mem or

                              brcm,bcm7268-avs-cpu-data-mem

- reg: Specifies base physical address and size of the registers.

- interrupts: The interrupt that the AVS CPU will use to interrupt the host

              when a command completed.

- interrupt-parent: The interrupt controller the above interrupt is routed

                    through.

- interrupt-names: The name of the interrupt used to interrupt the host.

Optional properties:

- None

Node brcm,avs-cpu-l2-intr

-------------------------

Required properties:

- compatible: must include: brcm,avs-cpu-l2-intr and

              should include: one of brcm,bcm7271-avs-cpu-l2-intr or

                              brcm,bcm7268-avs-cpu-l2-intr

- reg: Specifies base physical address and size of the registers.

Optional properties:

- None

Example

=======

	avs_host_l2_intc: interrupt-controller@f04d1200 {

		#interrupt-cells = <1>;

		compatible = "brcm,l2-intc";

		interrupt-parent = <&intc>;

		reg = <0xf04d1200 0x48>;

		interrupt-controller;

		interrupts = <0x0 0x19 0x0>;

		interrupt-names = "avs";

	};

	avs-cpu-data-mem@f04c4000 {

		compatible = "brcm,bcm7271-avs-cpu-data-mem",

				"brcm,avs-cpu-data-mem";

		reg = <0xf04c4000 0x60>;

		interrupts = <0x1a>;

		interrupt-parent = <&avs_host_l2_intc>;

		interrupt-names = "sw_intr";

	};

	avs-cpu-l2-intr@f04d1100 {

		compatible = "brcm,bcm7271-avs-cpu-l2-intr",

				"brcm,avs-cpu-l2-intr";

		reg = <0xf04d1100 0x10>;

	};

		       disable

		         Do not enable intel_pstate as the default

		         scaling driver for the supported processors

		       passive

			 Use intel_pstate as a scaling driver, but configure it

			 to work with generic cpufreq governors (instead of

			 enabling its internal governor).  This mode cannot be

			 used along with the hardware-managed P-states (HWP)

			 feature.

		       force

			 Enable intel_pstate on systems that prohibit it by default

			 in favor of acpi-cpufreq. Forcing the intel_pstate driver

			Description Table, specifies preferred power management

			profile as "Enterprise Server" or "Performance Server",

			then this feature is turned on by default.

		per_cpu_perf_limits

			Allow per-logical-CPU P-State performance control limits using

			cpufreq sysfs interface

	intremap=	[X86-64, Intel-IOMMU]

			on	enable Interrupt Remapping (default)

S:	Maintained

F:	drivers/mtd/nand/brcmnand/

BROADCOM STB AVS CPUFREQ DRIVER

M:	Markus Mayer <mmayer@broadcom.com>

M:	bcm-kernel-feedback-list@broadcom.com

L:	linux-pm@vger.kernel.org

S:	Maintained

F:	Documentation/devicetree/bindings/cpufreq/brcm,stb-avs-cpu-freq.txt

F:	drivers/cpufreq/brcmstb*

BROADCOM SPECIFIC AMBA DRIVER (BCMA)

M:	Rafał Miłecki <zajec5@gmail.com>

L:	linux-wireless@vger.kernel.org

S:	Maintained

T:	git git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git

T:	git git://git.linaro.org/people/vireshk/linux.git (For ARM Updates)

B:	https://bugzilla.kernel.org

F:	Documentation/cpu-freq/

F:	drivers/cpufreq/

F:	include/linux/cpufreq.h