diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-devfreq | 54 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/devfreq/exynos-bus.txt | 71 |
2 files changed, 101 insertions, 24 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq index b8ebff4b1c4c..386bc230a33d 100644 --- a/Documentation/ABI/testing/sysfs-class-devfreq +++ b/Documentation/ABI/testing/sysfs-class-devfreq @@ -37,20 +37,6 @@ Description: The /sys/class/devfreq/.../target_freq shows the next governor predicted target frequency of the corresponding devfreq object. -What: /sys/class/devfreq/.../polling_interval -Date: September 2011 -Contact: MyungJoo Ham <myungjoo.ham@samsung.com> -Description: - The /sys/class/devfreq/.../polling_interval shows and sets - the requested polling interval of the corresponding devfreq - object. The values are represented in ms. If the value is - less than 1 jiffy, it is considered to be 0, which means - no polling. This value is meaningless if the governor is - not polling; thus. If the governor is not using - devfreq-provided central polling - (/sys/class/devfreq/.../central_polling is 0), this value - may be useless. - What: /sys/class/devfreq/.../trans_stat Date: October 2012 Contact: MyungJoo Ham <myungjoo.ham@samsung.com> @@ -66,14 +52,6 @@ Description: echo 0 > /sys/class/devfreq/.../trans_stat -What: /sys/class/devfreq/.../userspace/set_freq -Date: September 2011 -Contact: MyungJoo Ham <myungjoo.ham@samsung.com> -Description: - The /sys/class/devfreq/.../userspace/set_freq shows and - sets the requested frequency for the devfreq object if - userspace governor is in effect. - What: /sys/class/devfreq/.../available_frequencies Date: October 2012 Contact: Nishanth Menon <nm@ti.com> @@ -110,6 +88,35 @@ Description: The max_freq overrides min_freq because max_freq may be used to throttle devices to avoid overheating. +What: /sys/class/devfreq/.../polling_interval +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../polling_interval shows and sets + the requested polling interval of the corresponding devfreq + object. The values are represented in ms. If the value is + less than 1 jiffy, it is considered to be 0, which means + no polling. This value is meaningless if the governor is + not polling; thus. If the governor is not using + devfreq-provided central polling + (/sys/class/devfreq/.../central_polling is 0), this value + may be useless. + + A list of governors that support the node: + - simple_ondmenad + - tegra_actmon + +What: /sys/class/devfreq/.../userspace/set_freq +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../userspace/set_freq shows and + sets the requested frequency for the devfreq object if + userspace governor is in effect. + + A list of governors that support the node: + - userspace + What: /sys/class/devfreq/.../timer Date: July 2020 Contact: Chanwoo Choi <cw00.choi@samsung.com> @@ -122,3 +129,6 @@ Description: echo deferrable > /sys/class/devfreq/.../timer echo delayed > /sys/class/devfreq/.../timer + + A list of governors that support the node: + - simple_ondemand diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt index e71f752cc18f..bcaa2c08ac11 100644 --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt @@ -51,6 +51,19 @@ Optional properties only for parent bus device: - exynos,saturation-ratio: the percentage value which is used to calibrate the performance count against total cycle count. +Optional properties for the interconnect functionality (QoS frequency +constraints): +- #interconnect-cells: should be 0. +- interconnects: as documented in ../interconnect.txt, describes a path at the + higher level interconnects used by this interconnect provider. + If this interconnect provider is directly linked to a top level interconnect + provider the property contains only one phandle. The provider extends + the interconnect graph by linking its node to a node registered by provider + pointed to by first phandle in the 'interconnects' property. + +- samsung,data-clock-ratio: ratio of the data throughput in B/s to minimum data + clock frequency in Hz, default value is 8 when this property is missing. + Detailed correlation between sub-blocks and power line according to Exynos SoC: - In case of Exynos3250, there are two power line as following: VDD_MIF |--- DMC @@ -135,7 +148,7 @@ Detailed correlation between sub-blocks and power line according to Exynos SoC: |--- PERIC (Fixed clock rate) |--- FSYS (Fixed clock rate) -Example1: +Example 1: Show the AXI buses of Exynos3250 SoC. Exynos3250 divides the buses to power line (regulator). The MIF (Memory Interface) AXI bus is used to transfer data between DRAM and CPU and uses the VDD_MIF regulator. @@ -184,7 +197,7 @@ Example1: |L5 |200000 |200000 |400000 |300000 | ||1000000 | ---------------------------------------------------------- -Example2 : +Example 2: The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi is listed below: @@ -419,3 +432,57 @@ Example2 : devfreq = <&bus_leftbus>; status = "okay"; }; + +Example 3: + An interconnect path "bus_display -- bus_leftbus -- bus_dmc" on + Exynos4412 SoC with video mixer as an interconnect consumer device. + + soc { + bus_dmc: bus_dmc { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_DIV_DMC>; + clock-names = "bus"; + operating-points-v2 = <&bus_dmc_opp_table>; + samsung,data-clock-ratio = <4>; + #interconnect-cells = <0>; + }; + + bus_leftbus: bus_leftbus { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_DIV_GDL>; + clock-names = "bus"; + operating-points-v2 = <&bus_leftbus_opp_table>; + #interconnect-cells = <0>; + interconnects = <&bus_dmc>; + }; + + bus_display: bus_display { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_ACLK160>; + clock-names = "bus"; + operating-points-v2 = <&bus_display_opp_table>; + #interconnect-cells = <0>; + interconnects = <&bus_leftbus &bus_dmc>; + }; + + bus_dmc_opp_table: opp_table1 { + compatible = "operating-points-v2"; + /* ... */ + } + + bus_leftbus_opp_table: opp_table3 { + compatible = "operating-points-v2"; + /* ... */ + }; + + bus_display_opp_table: opp_table4 { + compatible = "operating-points-v2"; + /* .. */ + }; + + &mixer { + compatible = "samsung,exynos4212-mixer"; + interconnects = <&bus_display &bus_dmc>; + /* ... */ + }; + }; |