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dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema

Message ID 20220626125238.57479-1-krzysztof.kozlowski@linaro.org (mailing list archive)
State New
Headers show
Series dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema | expand

Commit Message

Krzysztof Kozlowski June 26, 2022, 12:52 p.m. UTC
Convert the Samsung Exynos SoC Bus and Interconnect bindings to DT
schema.

Vast parts of descritpion and example were copied, so keep license as
GPL-2.0-only.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../bindings/devfreq/exynos-bus.txt           | 488 ------------------
 .../interconnect/samsung,exynos-bus.yaml      | 290 +++++++++++
 MAINTAINERS                                   |   2 +-
 3 files changed, 291 insertions(+), 489 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/devfreq/exynos-bus.txt
 create mode 100644 Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml

Comments

Chanwoo Choi June 29, 2022, 7:39 p.m. UTC | #1
On 22. 6. 26. 21:52, Krzysztof Kozlowski wrote:
> Convert the Samsung Exynos SoC Bus and Interconnect bindings to DT
> schema.
> 
> Vast parts of descritpion and example were copied, so keep license as
> GPL-2.0-only.
> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>  .../bindings/devfreq/exynos-bus.txt           | 488 ------------------
>  .../interconnect/samsung,exynos-bus.yaml      | 290 +++++++++++
>  MAINTAINERS                                   |   2 +-
>  3 files changed, 291 insertions(+), 489 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>  create mode 100644 Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
> 
> diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> deleted file mode 100644
> index bcaa2c08ac11..000000000000
> --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> +++ /dev/null
> @@ -1,488 +0,0 @@
> -* Generic Exynos Bus frequency device
> -
> -The Samsung Exynos SoC has many buses for data transfer between DRAM
> -and sub-blocks in SoC. Most Exynos SoCs share the common architecture
> -for buses. Generally, each bus of Exynos SoC includes a source clock
> -and a power line, which are able to change the clock frequency
> -of the bus in runtime. To monitor the usage of each bus in runtime,
> -the driver uses the PPMU (Platform Performance Monitoring Unit), which
> -is able to measure the current load of sub-blocks.
> -
> -The Exynos SoC includes the various sub-blocks which have the each AXI bus.
> -The each AXI bus has the owned source clock but, has not the only owned
> -power line. The power line might be shared among one more sub-blocks.
> -So, we can divide into two type of device as the role of each sub-block.
> -There are two type of bus devices as following:
> -- parent bus device
> -- passive bus device
> -
> -Basically, parent and passive bus device share the same power line.
> -The parent bus device can only change the voltage of shared power line
> -and the rest bus devices (passive bus device) depend on the decision of
> -the parent bus device. If there are three blocks which share the VDD_xxx
> -power line, Only one block should be parent device and then the rest blocks
> -should depend on the parent device as passive device.
> -
> -	VDD_xxx |--- A block (parent)
> -		|--- B block (passive)
> -		|--- C block (passive)
> -
> -There are a little different composition among Exynos SoC because each Exynos
> -SoC has different sub-blocks. Therefore, such difference should be specified
> -in devicetree file instead of each device driver. In result, this driver
> -is able to support the bus frequency for all Exynos SoCs.
> -
> -Required properties for all bus devices:
> -- compatible: Should be "samsung,exynos-bus".
> -- clock-names : the name of clock used by the bus, "bus".
> -- clocks : phandles for clock specified in "clock-names" property.
> -- operating-points-v2: the OPP table including frequency/voltage information
> -  to support DVFS (Dynamic Voltage/Frequency Scaling) feature.
> -
> -Required properties only for parent bus device:
> -- vdd-supply: the regulator to provide the buses with the voltage.
> -- devfreq-events: the devfreq-event device to monitor the current utilization
> -  of buses.
> -
> -Required properties only for passive bus device:
> -- devfreq: the parent bus device.
> -
> -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
> -
> -	VDD_INT |--- LEFTBUS (parent device)
> -		|--- PERIL
> -		|--- MFC
> -		|--- G3D
> -		|--- RIGHTBUS
> -		|--- PERIR
> -		|--- FSYS
> -		|--- LCD0
> -		|--- PERIR
> -		|--- ISP
> -		|--- CAM
> -
> -- In case of Exynos4210, there is one power line as following:
> -	VDD_INT |--- DMC (parent device)
> -		|--- LEFTBUS
> -		|--- PERIL
> -		|--- MFC(L)
> -		|--- G3D
> -		|--- TV
> -		|--- LCD0
> -		|--- RIGHTBUS
> -		|--- PERIR
> -		|--- MFC(R)
> -		|--- CAM
> -		|--- FSYS
> -		|--- GPS
> -		|--- LCD0
> -		|--- LCD1
> -
> -- In case of Exynos4x12, there are two power line as following:
> -	VDD_MIF |--- DMC
> -
> -	VDD_INT |--- LEFTBUS (parent device)
> -		|--- PERIL
> -		|--- MFC(L)
> -		|--- G3D
> -		|--- TV
> -		|--- IMAGE
> -		|--- RIGHTBUS
> -		|--- PERIR
> -		|--- MFC(R)
> -		|--- CAM
> -		|--- FSYS
> -		|--- GPS
> -		|--- LCD0
> -		|--- ISP
> -
> -- In case of Exynos5422, there are two power line as following:
> -	VDD_MIF |--- DREX 0 (parent device, DRAM EXpress controller)
> -	        |--- DREX 1
> -
> -	VDD_INT |--- NoC_Core (parent device)
> -		|--- G2D
> -		|--- G3D
> -		|--- DISP1
> -		|--- NoC_WCORE
> -		|--- GSCL
> -		|--- MSCL
> -		|--- ISP
> -		|--- MFC
> -		|--- GEN
> -		|--- PERIS
> -		|--- PERIC
> -		|--- FSYS
> -		|--- FSYS2
> -
> -- In case of Exynos5433, there is VDD_INT power line as following:
> -	VDD_INT |--- G2D (parent device)
> -		|--- MSCL
> -		|--- GSCL
> -		|--- JPEG
> -		|--- MFC
> -		|--- HEVC
> -		|--- BUS0
> -		|--- BUS1
> -		|--- BUS2
> -		|--- PERIS (Fixed clock rate)
> -		|--- PERIC (Fixed clock rate)
> -		|--- FSYS  (Fixed clock rate)
> -
> -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.
> -
> -	- MIF (Memory Interface) block
> -	: VDD_MIF |--- DMC (Dynamic Memory Controller)
> -
> -	- INT (Internal) block
> -	: VDD_INT |--- LEFTBUS (parent device)
> -		  |--- PERIL
> -		  |--- MFC
> -		  |--- G3D
> -		  |--- RIGHTBUS
> -		  |--- FSYS
> -		  |--- LCD0
> -		  |--- PERIR
> -		  |--- ISP
> -		  |--- CAM
> -
> -	- MIF bus's frequency/voltage table
> -	-----------------------
> -	|Lv| Freq   | Voltage |
> -	-----------------------
> -	|L1| 50000  |800000   |
> -	|L2| 100000 |800000   |
> -	|L3| 134000 |800000   |
> -	|L4| 200000 |825000   |
> -	|L5| 400000 |875000   |
> -	-----------------------
> -
> -	- INT bus's frequency/voltage table
> -	----------------------------------------------------------
> -	|Block|LEFTBUS|RIGHTBUS|MCUISP |ISP    |PERIL  ||VDD_INT |
> -	| name|       |LCD0    |       |       |       ||        |
> -	|     |       |FSYS    |       |       |       ||        |
> -	|     |       |MFC     |       |       |       ||        |
> -	----------------------------------------------------------
> -	|Mode |*parent|passive |passive|passive|passive||        |
> -	----------------------------------------------------------
> -	|Lv   |Frequency                               ||Voltage |
> -	----------------------------------------------------------
> -	|L1   |50000  |50000   |50000  |50000  |50000  ||900000  |
> -	|L2   |80000  |80000   |80000  |80000  |80000  ||900000  |
> -	|L3   |100000 |100000  |100000 |100000 |100000 ||1000000 |
> -	|L4   |134000 |134000  |200000 |200000 |       ||1000000 |
> -	|L5   |200000 |200000  |400000 |300000 |       ||1000000 |
> -	----------------------------------------------------------
> -
> -Example 2:
> -	The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi
> -	is listed below:
> -
> -	bus_dmc: bus_dmc {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu_dmc CLK_DIV_DMC>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_dmc_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_dmc_opp_table: opp_table1 {
> -		compatible = "operating-points-v2";
> -		opp-shared;
> -
> -		opp-50000000 {
> -			opp-hz = /bits/ 64 <50000000>;
> -			opp-microvolt = <800000>;
> -		};
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -			opp-microvolt = <800000>;
> -		};
> -		opp-134000000 {
> -			opp-hz = /bits/ 64 <134000000>;
> -			opp-microvolt = <800000>;
> -		};
> -		opp-200000000 {
> -			opp-hz = /bits/ 64 <200000000>;
> -			opp-microvolt = <825000>;
> -		};
> -		opp-400000000 {
> -			opp-hz = /bits/ 64 <400000000>;
> -			opp-microvolt = <875000>;
> -		};
> -	};
> -
> -	bus_leftbus: bus_leftbus {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_GDL>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_leftbus_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_rightbus: bus_rightbus {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_GDR>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_leftbus_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_lcd0: bus_lcd0 {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_ACLK_160>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_leftbus_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_fsys: bus_fsys {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_ACLK_200>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_leftbus_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_mcuisp: bus_mcuisp {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_ACLK_400_MCUISP>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_mcuisp_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_isp: bus_isp {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_ACLK_266>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_isp_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_peril: bus_peril {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_DIV_ACLK_100>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_peril_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_mfc: bus_mfc {
> -		compatible = "samsung,exynos-bus";
> -		clocks = <&cmu CLK_SCLK_MFC>;
> -		clock-names = "bus";
> -		operating-points-v2 = <&bus_leftbus_opp_table>;
> -		status = "disabled";
> -	};
> -
> -	bus_leftbus_opp_table: opp_table1 {
> -		compatible = "operating-points-v2";
> -		opp-shared;
> -
> -		opp-50000000 {
> -			opp-hz = /bits/ 64 <50000000>;
> -			opp-microvolt = <900000>;
> -		};
> -		opp-80000000 {
> -			opp-hz = /bits/ 64 <80000000>;
> -			opp-microvolt = <900000>;
> -		};
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -			opp-microvolt = <1000000>;
> -		};
> -		opp-134000000 {
> -			opp-hz = /bits/ 64 <134000000>;
> -			opp-microvolt = <1000000>;
> -		};
> -		opp-200000000 {
> -			opp-hz = /bits/ 64 <200000000>;
> -			opp-microvolt = <1000000>;
> -		};
> -	};
> -
> -	bus_mcuisp_opp_table: opp_table2 {
> -		compatible = "operating-points-v2";
> -		opp-shared;
> -
> -		opp-50000000 {
> -			opp-hz = /bits/ 64 <50000000>;
> -		};
> -		opp-80000000 {
> -			opp-hz = /bits/ 64 <80000000>;
> -		};
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -		};
> -		opp-200000000 {
> -			opp-hz = /bits/ 64 <200000000>;
> -		};
> -		opp-400000000 {
> -			opp-hz = /bits/ 64 <400000000>;
> -		};
> -	};
> -
> -	bus_isp_opp_table: opp_table3 {
> -		compatible = "operating-points-v2";
> -		opp-shared;
> -
> -		opp-50000000 {
> -			opp-hz = /bits/ 64 <50000000>;
> -		};
> -		opp-80000000 {
> -			opp-hz = /bits/ 64 <80000000>;
> -		};
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -		};
> -		opp-200000000 {
> -			opp-hz = /bits/ 64 <200000000>;
> -		};
> -		opp-300000000 {
> -			opp-hz = /bits/ 64 <300000000>;
> -		};
> -	};
> -
> -	bus_peril_opp_table: opp_table4 {
> -		compatible = "operating-points-v2";
> -		opp-shared;
> -
> -		opp-50000000 {
> -			opp-hz = /bits/ 64 <50000000>;
> -		};
> -		opp-80000000 {
> -			opp-hz = /bits/ 64 <80000000>;
> -		};
> -		opp-100000000 {
> -			opp-hz = /bits/ 64 <100000000>;
> -		};
> -	};
> -
> -
> -	Usage case to handle the frequency and voltage of bus on runtime
> -	in exynos3250-rinato.dts is listed below:
> -
> -	&bus_dmc {
> -		devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
> -		vdd-supply = <&buck1_reg>;	/* VDD_MIF */
> -		status = "okay";
> -	};
> -
> -	&bus_leftbus {
> -		devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
> -		vdd-supply = <&buck3_reg>;
> -		status = "okay";
> -	};
> -
> -	&bus_rightbus {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_lcd0 {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_fsys {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_mcuisp {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_isp {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_peril {
> -		devfreq = <&bus_leftbus>;
> -		status = "okay";
> -	};
> -
> -	&bus_mfc {
> -		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>;
> -			/* ... */
> -		};
> -	};
> diff --git a/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml b/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
> new file mode 100644
> index 000000000000..ad9ed596dfef
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
> @@ -0,0 +1,290 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/interconnect/samsung,exynos-bus.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Samsung Exynos SoC Bus and Interconnect
> +
> +maintainers:
> +  - Chanwoo Choi <cw00.choi@samsung.com>
> +  - Krzysztof Kozlowski <krzk@kernel.org>
> +
> +description: |
> +  The Samsung Exynos SoC has many buses for data transfer between DRAM and
> +  sub-blocks in SoC. Most Exynos SoCs share the common architecture for buses.
> +  Generally, each bus of Exynos SoC includes a source clock and a power line,
> +  which are able to change the clock frequency of the bus in runtime. To
> +  monitor the usage of each bus in runtime, the driver uses the PPMU (Platform
> +  Performance Monitoring Unit), which is able to measure the current load of
> +  sub-blocks.
> +
> +  The Exynos SoC includes the various sub-blocks which have the each AXI bus.
> +  The each AXI bus has the owned source clock but, has not the only owned power
> +  line. The power line might be shared among one more sub-blocks.  So, we can
> +  divide into two type of device as the role of each sub-block.  There are two
> +  type of bus devices as following::
> +   - parent bus device
> +   - passive bus device
> +
> +  Basically, parent and passive bus device share the same power line.  The
> +  parent bus device can only change the voltage of shared power line and the
> +  rest bus devices (passive bus device) depend on the decision of the parent
> +  bus device. If there are three blocks which share the VDD_xxx power line,
> +  Only one block should be parent device and then the rest blocks should depend
> +  on the parent device as passive device.
> +
> +    VDD_xxx |--- A block (parent)
> +      |--- B block (passive)
> +      |--- C block (passive)
> +
> +  There are a little different composition among Exynos SoC because each Exynos
> +  SoC has different sub-blocks. Therefore, such difference should be specified
> +  in devicetree file instead of each device driver. In result, this driver is
> +  able to support the bus frequency for all Exynos SoCs.
> +
> +  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 (Dynamic Memory Controller)
> +
> +     VDD_INT |--- LEFTBUS (parent device)
> +       |--- PERIL
> +       |--- MFC
> +       |--- G3D
> +       |--- RIGHTBUS
> +       |--- PERIR
> +       |--- FSYS
> +       |--- LCD0
> +       |--- PERIR
> +       |--- ISP
> +       |--- CAM
> +
> +     - MIF bus's frequency/voltage table
> +       -----------------------
> +       |Lv| Freq   | Voltage |
> +       -----------------------
> +       |L1| 50000  |800000   |
> +       |L2| 100000 |800000   |
> +       |L3| 134000 |800000   |
> +       |L4| 200000 |825000   |
> +       |L5| 400000 |875000   |
> +       -----------------------
> +
> +     - INT bus's frequency/voltage table
> +       ----------------------------------------------------------
> +       |Block|LEFTBUS|RIGHTBUS|MCUISP |ISP    |PERIL  ||VDD_INT |
> +       | name|       |LCD0    |       |       |       ||        |
> +       |     |       |FSYS    |       |       |       ||        |
> +       |     |       |MFC     |       |       |       ||        |
> +       ----------------------------------------------------------
> +       |Mode |*parent|passive |passive|passive|passive||        |
> +       ----------------------------------------------------------
> +       |Lv   |Frequency                               ||Voltage |
> +       ----------------------------------------------------------
> +       |L1   |50000  |50000   |50000  |50000  |50000  ||900000  |
> +       |L2   |80000  |80000   |80000  |80000  |80000  ||900000  |
> +       |L3   |100000 |100000  |100000 |100000 |100000 ||1000000 |
> +       |L4   |134000 |134000  |200000 |200000 |       ||1000000 |
> +       |L5   |200000 |200000  |400000 |300000 |       ||1000000 |
> +       ----------------------------------------------------------
> +
> +   - In case of Exynos4210, there is one power line as following::
> +     VDD_INT |--- DMC (parent device, Dynamic Memory Controller)
> +       |--- LEFTBUS
> +       |--- PERIL
> +       |--- MFC(L)
> +       |--- G3D
> +       |--- TV
> +       |--- LCD0
> +       |--- RIGHTBUS
> +       |--- PERIR
> +       |--- MFC(R)
> +       |--- CAM
> +       |--- FSYS
> +       |--- GPS
> +       |--- LCD0
> +       |--- LCD1
> +
> +   - In case of Exynos4x12, there are two power line as following::
> +     VDD_MIF |--- DMC (Dynamic Memory Controller)
> +
> +     VDD_INT |--- LEFTBUS (parent device)
> +       |--- PERIL
> +       |--- MFC(L)
> +       |--- G3D
> +       |--- TV
> +       |--- IMAGE
> +       |--- RIGHTBUS
> +       |--- PERIR
> +       |--- MFC(R)
> +       |--- CAM
> +       |--- FSYS
> +       |--- GPS
> +       |--- LCD0
> +       |--- ISP
> +
> +   - In case of Exynos5422, there are two power line as following::
> +     VDD_MIF |--- DREX 0 (parent device, DRAM EXpress controller)
> +             |--- DREX 1
> +
> +     VDD_INT |--- NoC_Core (parent device)
> +       |--- G2D
> +       |--- G3D
> +       |--- DISP1
> +       |--- NoC_WCORE
> +       |--- GSCL
> +       |--- MSCL
> +       |--- ISP
> +       |--- MFC
> +       |--- GEN
> +       |--- PERIS
> +       |--- PERIC
> +       |--- FSYS
> +       |--- FSYS2
> +
> +   - In case of Exynos5433, there is VDD_INT power line as following::
> +     VDD_INT |--- G2D (parent device)
> +       |--- MSCL
> +       |--- GSCL
> +       |--- JPEG
> +       |--- MFC
> +       |--- HEVC
> +       |--- BUS0
> +       |--- BUS1
> +       |--- BUS2
> +       |--- PERIS (Fixed clock rate)
> +       |--- PERIC (Fixed clock rate)
> +       |--- FSYS  (Fixed clock rate)
> +
> +properties:
> +  compatible:
> +    enum:
> +      - samsung,exynos-bus
> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    items:
> +      - const: bus
> +
> +  devfreq:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      Parent bus device. Valid and required only for the passive bus devices.
> +
> +  devfreq-events:
> +    $ref: /schemas/types.yaml#/definitions/phandle-array
> +    minItems: 1
> +    maxItems: 4
> +    description:
> +      Devfreq-event device to monitor the current utilization of buses. Valid
> +      and required only for the parent bus devices.
> +
> +  exynos,saturation-ratio:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Percentage value which is used to calibrate the performance count against
> +      total cycle count.  Valid only for the parent bus devices.
> +
> +  '#interconnect-cells':
> +    const: 0
> +
> +  interconnects:
> +    minItems: 1
> +    maxItems: 2
> +
> +  operating-points-v2: true
> +
> +  samsung,data-clock-ratio:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    default: 8
> +    description:
> +      Ratio of the data throughput in B/s to minimum data clock frequency in
> +      Hz.
> +
> +  vdd-supply:
> +    description:
> +      Main bus power rail. Valid and required only for the parent bus devices.
> +
> +required:
> +  - compatible
> +  - clocks
> +  - clock-names
> +  - operating-points-v2
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/exynos3250.h>
> +
> +    bus-dmc {
> +        compatible = "samsung,exynos-bus";
> +        clocks = <&cmu_dmc CLK_DIV_DMC>;
> +        clock-names = "bus";
> +        operating-points-v2 = <&bus_dmc_opp_table>;
> +        devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
> +        vdd-supply = <&buck1_reg>;
> +    };
> +
> +    ppmu_dmc0: ppmu@106a0000 {
> +        compatible = "samsung,exynos-ppmu";
> +        reg = <0x106a0000 0x2000>;
> +        events {
> +            ppmu_dmc0_3: ppmu-event3-dmc0 {
> +                event-name = "ppmu-event3-dmc0";
> +            };
> +        };
> +    };
> +
> +    bus_leftbus: bus-leftbus {
> +        compatible = "samsung,exynos-bus";
> +        clocks = <&cmu CLK_DIV_GDL>;
> +        clock-names = "bus";
> +        operating-points-v2 = <&bus_leftbus_opp_table>;
> +        devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
> +        vdd-supply = <&buck3_reg>;
> +    };
> +
> +    bus-rightbus {
> +        compatible = "samsung,exynos-bus";
> +        clocks = <&cmu CLK_DIV_GDR>;
> +        clock-names = "bus";
> +        operating-points-v2 = <&bus_leftbus_opp_table>;
> +        devfreq = <&bus_leftbus>;
> +    };
> +
> +  - |
> +    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>;
> +        devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
> +        vdd-supply = <&buck1_reg>;
> +    };
> +
> +    leftbus: bus-leftbus {
> +        compatible = "samsung,exynos-bus";
> +        clocks = <&clock CLK_DIV_GDL>;
> +        clock-names = "bus";
> +        operating-points-v2 = <&bus_leftbus_opp_table>;
> +        interconnects = <&dmc>;
> +        #interconnect-cells = <0>;
> +        devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
> +        vdd-supply = <&buck3_reg>;
> +    };
> +
> +    display: bus-display {
> +        compatible = "samsung,exynos-bus";
> +        clocks = <&clock CLK_DIV_ACLK_266>;
> +        clock-names = "bus";
> +        operating-points-v2 = <&bus_display_opp_table>;
> +        interconnects = <&leftbus &dmc>;
> +        #interconnect-cells = <0>;
> +        devfreq = <&leftbus>;
> +    };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7c9187635801..19875f60ebb1 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4328,7 +4328,7 @@ L:	linux-pm@vger.kernel.org
>  L:	linux-samsung-soc@vger.kernel.org
>  S:	Maintained
>  T:	git git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git
> -F:	Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> +F:	Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
>  F:	drivers/devfreq/exynos-bus.c
>  
>  BUSLOGIC SCSI DRIVER

Applied it.
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
deleted file mode 100644
index bcaa2c08ac11..000000000000
--- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
+++ /dev/null
@@ -1,488 +0,0 @@ 
-* Generic Exynos Bus frequency device
-
-The Samsung Exynos SoC has many buses for data transfer between DRAM
-and sub-blocks in SoC. Most Exynos SoCs share the common architecture
-for buses. Generally, each bus of Exynos SoC includes a source clock
-and a power line, which are able to change the clock frequency
-of the bus in runtime. To monitor the usage of each bus in runtime,
-the driver uses the PPMU (Platform Performance Monitoring Unit), which
-is able to measure the current load of sub-blocks.
-
-The Exynos SoC includes the various sub-blocks which have the each AXI bus.
-The each AXI bus has the owned source clock but, has not the only owned
-power line. The power line might be shared among one more sub-blocks.
-So, we can divide into two type of device as the role of each sub-block.
-There are two type of bus devices as following:
-- parent bus device
-- passive bus device
-
-Basically, parent and passive bus device share the same power line.
-The parent bus device can only change the voltage of shared power line
-and the rest bus devices (passive bus device) depend on the decision of
-the parent bus device. If there are three blocks which share the VDD_xxx
-power line, Only one block should be parent device and then the rest blocks
-should depend on the parent device as passive device.
-
-	VDD_xxx |--- A block (parent)
-		|--- B block (passive)
-		|--- C block (passive)
-
-There are a little different composition among Exynos SoC because each Exynos
-SoC has different sub-blocks. Therefore, such difference should be specified
-in devicetree file instead of each device driver. In result, this driver
-is able to support the bus frequency for all Exynos SoCs.
-
-Required properties for all bus devices:
-- compatible: Should be "samsung,exynos-bus".
-- clock-names : the name of clock used by the bus, "bus".
-- clocks : phandles for clock specified in "clock-names" property.
-- operating-points-v2: the OPP table including frequency/voltage information
-  to support DVFS (Dynamic Voltage/Frequency Scaling) feature.
-
-Required properties only for parent bus device:
-- vdd-supply: the regulator to provide the buses with the voltage.
-- devfreq-events: the devfreq-event device to monitor the current utilization
-  of buses.
-
-Required properties only for passive bus device:
-- devfreq: the parent bus device.
-
-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
-
-	VDD_INT |--- LEFTBUS (parent device)
-		|--- PERIL
-		|--- MFC
-		|--- G3D
-		|--- RIGHTBUS
-		|--- PERIR
-		|--- FSYS
-		|--- LCD0
-		|--- PERIR
-		|--- ISP
-		|--- CAM
-
-- In case of Exynos4210, there is one power line as following:
-	VDD_INT |--- DMC (parent device)
-		|--- LEFTBUS
-		|--- PERIL
-		|--- MFC(L)
-		|--- G3D
-		|--- TV
-		|--- LCD0
-		|--- RIGHTBUS
-		|--- PERIR
-		|--- MFC(R)
-		|--- CAM
-		|--- FSYS
-		|--- GPS
-		|--- LCD0
-		|--- LCD1
-
-- In case of Exynos4x12, there are two power line as following:
-	VDD_MIF |--- DMC
-
-	VDD_INT |--- LEFTBUS (parent device)
-		|--- PERIL
-		|--- MFC(L)
-		|--- G3D
-		|--- TV
-		|--- IMAGE
-		|--- RIGHTBUS
-		|--- PERIR
-		|--- MFC(R)
-		|--- CAM
-		|--- FSYS
-		|--- GPS
-		|--- LCD0
-		|--- ISP
-
-- In case of Exynos5422, there are two power line as following:
-	VDD_MIF |--- DREX 0 (parent device, DRAM EXpress controller)
-	        |--- DREX 1
-
-	VDD_INT |--- NoC_Core (parent device)
-		|--- G2D
-		|--- G3D
-		|--- DISP1
-		|--- NoC_WCORE
-		|--- GSCL
-		|--- MSCL
-		|--- ISP
-		|--- MFC
-		|--- GEN
-		|--- PERIS
-		|--- PERIC
-		|--- FSYS
-		|--- FSYS2
-
-- In case of Exynos5433, there is VDD_INT power line as following:
-	VDD_INT |--- G2D (parent device)
-		|--- MSCL
-		|--- GSCL
-		|--- JPEG
-		|--- MFC
-		|--- HEVC
-		|--- BUS0
-		|--- BUS1
-		|--- BUS2
-		|--- PERIS (Fixed clock rate)
-		|--- PERIC (Fixed clock rate)
-		|--- FSYS  (Fixed clock rate)
-
-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.
-
-	- MIF (Memory Interface) block
-	: VDD_MIF |--- DMC (Dynamic Memory Controller)
-
-	- INT (Internal) block
-	: VDD_INT |--- LEFTBUS (parent device)
-		  |--- PERIL
-		  |--- MFC
-		  |--- G3D
-		  |--- RIGHTBUS
-		  |--- FSYS
-		  |--- LCD0
-		  |--- PERIR
-		  |--- ISP
-		  |--- CAM
-
-	- MIF bus's frequency/voltage table
-	-----------------------
-	|Lv| Freq   | Voltage |
-	-----------------------
-	|L1| 50000  |800000   |
-	|L2| 100000 |800000   |
-	|L3| 134000 |800000   |
-	|L4| 200000 |825000   |
-	|L5| 400000 |875000   |
-	-----------------------
-
-	- INT bus's frequency/voltage table
-	----------------------------------------------------------
-	|Block|LEFTBUS|RIGHTBUS|MCUISP |ISP    |PERIL  ||VDD_INT |
-	| name|       |LCD0    |       |       |       ||        |
-	|     |       |FSYS    |       |       |       ||        |
-	|     |       |MFC     |       |       |       ||        |
-	----------------------------------------------------------
-	|Mode |*parent|passive |passive|passive|passive||        |
-	----------------------------------------------------------
-	|Lv   |Frequency                               ||Voltage |
-	----------------------------------------------------------
-	|L1   |50000  |50000   |50000  |50000  |50000  ||900000  |
-	|L2   |80000  |80000   |80000  |80000  |80000  ||900000  |
-	|L3   |100000 |100000  |100000 |100000 |100000 ||1000000 |
-	|L4   |134000 |134000  |200000 |200000 |       ||1000000 |
-	|L5   |200000 |200000  |400000 |300000 |       ||1000000 |
-	----------------------------------------------------------
-
-Example 2:
-	The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi
-	is listed below:
-
-	bus_dmc: bus_dmc {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu_dmc CLK_DIV_DMC>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_dmc_opp_table>;
-		status = "disabled";
-	};
-
-	bus_dmc_opp_table: opp_table1 {
-		compatible = "operating-points-v2";
-		opp-shared;
-
-		opp-50000000 {
-			opp-hz = /bits/ 64 <50000000>;
-			opp-microvolt = <800000>;
-		};
-		opp-100000000 {
-			opp-hz = /bits/ 64 <100000000>;
-			opp-microvolt = <800000>;
-		};
-		opp-134000000 {
-			opp-hz = /bits/ 64 <134000000>;
-			opp-microvolt = <800000>;
-		};
-		opp-200000000 {
-			opp-hz = /bits/ 64 <200000000>;
-			opp-microvolt = <825000>;
-		};
-		opp-400000000 {
-			opp-hz = /bits/ 64 <400000000>;
-			opp-microvolt = <875000>;
-		};
-	};
-
-	bus_leftbus: bus_leftbus {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_GDL>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_leftbus_opp_table>;
-		status = "disabled";
-	};
-
-	bus_rightbus: bus_rightbus {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_GDR>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_leftbus_opp_table>;
-		status = "disabled";
-	};
-
-	bus_lcd0: bus_lcd0 {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_ACLK_160>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_leftbus_opp_table>;
-		status = "disabled";
-	};
-
-	bus_fsys: bus_fsys {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_ACLK_200>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_leftbus_opp_table>;
-		status = "disabled";
-	};
-
-	bus_mcuisp: bus_mcuisp {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_ACLK_400_MCUISP>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_mcuisp_opp_table>;
-		status = "disabled";
-	};
-
-	bus_isp: bus_isp {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_ACLK_266>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_isp_opp_table>;
-		status = "disabled";
-	};
-
-	bus_peril: bus_peril {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_DIV_ACLK_100>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_peril_opp_table>;
-		status = "disabled";
-	};
-
-	bus_mfc: bus_mfc {
-		compatible = "samsung,exynos-bus";
-		clocks = <&cmu CLK_SCLK_MFC>;
-		clock-names = "bus";
-		operating-points-v2 = <&bus_leftbus_opp_table>;
-		status = "disabled";
-	};
-
-	bus_leftbus_opp_table: opp_table1 {
-		compatible = "operating-points-v2";
-		opp-shared;
-
-		opp-50000000 {
-			opp-hz = /bits/ 64 <50000000>;
-			opp-microvolt = <900000>;
-		};
-		opp-80000000 {
-			opp-hz = /bits/ 64 <80000000>;
-			opp-microvolt = <900000>;
-		};
-		opp-100000000 {
-			opp-hz = /bits/ 64 <100000000>;
-			opp-microvolt = <1000000>;
-		};
-		opp-134000000 {
-			opp-hz = /bits/ 64 <134000000>;
-			opp-microvolt = <1000000>;
-		};
-		opp-200000000 {
-			opp-hz = /bits/ 64 <200000000>;
-			opp-microvolt = <1000000>;
-		};
-	};
-
-	bus_mcuisp_opp_table: opp_table2 {
-		compatible = "operating-points-v2";
-		opp-shared;
-
-		opp-50000000 {
-			opp-hz = /bits/ 64 <50000000>;
-		};
-		opp-80000000 {
-			opp-hz = /bits/ 64 <80000000>;
-		};
-		opp-100000000 {
-			opp-hz = /bits/ 64 <100000000>;
-		};
-		opp-200000000 {
-			opp-hz = /bits/ 64 <200000000>;
-		};
-		opp-400000000 {
-			opp-hz = /bits/ 64 <400000000>;
-		};
-	};
-
-	bus_isp_opp_table: opp_table3 {
-		compatible = "operating-points-v2";
-		opp-shared;
-
-		opp-50000000 {
-			opp-hz = /bits/ 64 <50000000>;
-		};
-		opp-80000000 {
-			opp-hz = /bits/ 64 <80000000>;
-		};
-		opp-100000000 {
-			opp-hz = /bits/ 64 <100000000>;
-		};
-		opp-200000000 {
-			opp-hz = /bits/ 64 <200000000>;
-		};
-		opp-300000000 {
-			opp-hz = /bits/ 64 <300000000>;
-		};
-	};
-
-	bus_peril_opp_table: opp_table4 {
-		compatible = "operating-points-v2";
-		opp-shared;
-
-		opp-50000000 {
-			opp-hz = /bits/ 64 <50000000>;
-		};
-		opp-80000000 {
-			opp-hz = /bits/ 64 <80000000>;
-		};
-		opp-100000000 {
-			opp-hz = /bits/ 64 <100000000>;
-		};
-	};
-
-
-	Usage case to handle the frequency and voltage of bus on runtime
-	in exynos3250-rinato.dts is listed below:
-
-	&bus_dmc {
-		devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
-		vdd-supply = <&buck1_reg>;	/* VDD_MIF */
-		status = "okay";
-	};
-
-	&bus_leftbus {
-		devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
-		vdd-supply = <&buck3_reg>;
-		status = "okay";
-	};
-
-	&bus_rightbus {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_lcd0 {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_fsys {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_mcuisp {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_isp {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_peril {
-		devfreq = <&bus_leftbus>;
-		status = "okay";
-	};
-
-	&bus_mfc {
-		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>;
-			/* ... */
-		};
-	};
diff --git a/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml b/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
new file mode 100644
index 000000000000..ad9ed596dfef
--- /dev/null
+++ b/Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
@@ -0,0 +1,290 @@ 
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interconnect/samsung,exynos-bus.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung Exynos SoC Bus and Interconnect
+
+maintainers:
+  - Chanwoo Choi <cw00.choi@samsung.com>
+  - Krzysztof Kozlowski <krzk@kernel.org>
+
+description: |
+  The Samsung Exynos SoC has many buses for data transfer between DRAM and
+  sub-blocks in SoC. Most Exynos SoCs share the common architecture for buses.
+  Generally, each bus of Exynos SoC includes a source clock and a power line,
+  which are able to change the clock frequency of the bus in runtime. To
+  monitor the usage of each bus in runtime, the driver uses the PPMU (Platform
+  Performance Monitoring Unit), which is able to measure the current load of
+  sub-blocks.
+
+  The Exynos SoC includes the various sub-blocks which have the each AXI bus.
+  The each AXI bus has the owned source clock but, has not the only owned power
+  line. The power line might be shared among one more sub-blocks.  So, we can
+  divide into two type of device as the role of each sub-block.  There are two
+  type of bus devices as following::
+   - parent bus device
+   - passive bus device
+
+  Basically, parent and passive bus device share the same power line.  The
+  parent bus device can only change the voltage of shared power line and the
+  rest bus devices (passive bus device) depend on the decision of the parent
+  bus device. If there are three blocks which share the VDD_xxx power line,
+  Only one block should be parent device and then the rest blocks should depend
+  on the parent device as passive device.
+
+    VDD_xxx |--- A block (parent)
+      |--- B block (passive)
+      |--- C block (passive)
+
+  There are a little different composition among Exynos SoC because each Exynos
+  SoC has different sub-blocks. Therefore, such difference should be specified
+  in devicetree file instead of each device driver. In result, this driver is
+  able to support the bus frequency for all Exynos SoCs.
+
+  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 (Dynamic Memory Controller)
+
+     VDD_INT |--- LEFTBUS (parent device)
+       |--- PERIL
+       |--- MFC
+       |--- G3D
+       |--- RIGHTBUS
+       |--- PERIR
+       |--- FSYS
+       |--- LCD0
+       |--- PERIR
+       |--- ISP
+       |--- CAM
+
+     - MIF bus's frequency/voltage table
+       -----------------------
+       |Lv| Freq   | Voltage |
+       -----------------------
+       |L1| 50000  |800000   |
+       |L2| 100000 |800000   |
+       |L3| 134000 |800000   |
+       |L4| 200000 |825000   |
+       |L5| 400000 |875000   |
+       -----------------------
+
+     - INT bus's frequency/voltage table
+       ----------------------------------------------------------
+       |Block|LEFTBUS|RIGHTBUS|MCUISP |ISP    |PERIL  ||VDD_INT |
+       | name|       |LCD0    |       |       |       ||        |
+       |     |       |FSYS    |       |       |       ||        |
+       |     |       |MFC     |       |       |       ||        |
+       ----------------------------------------------------------
+       |Mode |*parent|passive |passive|passive|passive||        |
+       ----------------------------------------------------------
+       |Lv   |Frequency                               ||Voltage |
+       ----------------------------------------------------------
+       |L1   |50000  |50000   |50000  |50000  |50000  ||900000  |
+       |L2   |80000  |80000   |80000  |80000  |80000  ||900000  |
+       |L3   |100000 |100000  |100000 |100000 |100000 ||1000000 |
+       |L4   |134000 |134000  |200000 |200000 |       ||1000000 |
+       |L5   |200000 |200000  |400000 |300000 |       ||1000000 |
+       ----------------------------------------------------------
+
+   - In case of Exynos4210, there is one power line as following::
+     VDD_INT |--- DMC (parent device, Dynamic Memory Controller)
+       |--- LEFTBUS
+       |--- PERIL
+       |--- MFC(L)
+       |--- G3D
+       |--- TV
+       |--- LCD0
+       |--- RIGHTBUS
+       |--- PERIR
+       |--- MFC(R)
+       |--- CAM
+       |--- FSYS
+       |--- GPS
+       |--- LCD0
+       |--- LCD1
+
+   - In case of Exynos4x12, there are two power line as following::
+     VDD_MIF |--- DMC (Dynamic Memory Controller)
+
+     VDD_INT |--- LEFTBUS (parent device)
+       |--- PERIL
+       |--- MFC(L)
+       |--- G3D
+       |--- TV
+       |--- IMAGE
+       |--- RIGHTBUS
+       |--- PERIR
+       |--- MFC(R)
+       |--- CAM
+       |--- FSYS
+       |--- GPS
+       |--- LCD0
+       |--- ISP
+
+   - In case of Exynos5422, there are two power line as following::
+     VDD_MIF |--- DREX 0 (parent device, DRAM EXpress controller)
+             |--- DREX 1
+
+     VDD_INT |--- NoC_Core (parent device)
+       |--- G2D
+       |--- G3D
+       |--- DISP1
+       |--- NoC_WCORE
+       |--- GSCL
+       |--- MSCL
+       |--- ISP
+       |--- MFC
+       |--- GEN
+       |--- PERIS
+       |--- PERIC
+       |--- FSYS
+       |--- FSYS2
+
+   - In case of Exynos5433, there is VDD_INT power line as following::
+     VDD_INT |--- G2D (parent device)
+       |--- MSCL
+       |--- GSCL
+       |--- JPEG
+       |--- MFC
+       |--- HEVC
+       |--- BUS0
+       |--- BUS1
+       |--- BUS2
+       |--- PERIS (Fixed clock rate)
+       |--- PERIC (Fixed clock rate)
+       |--- FSYS  (Fixed clock rate)
+
+properties:
+  compatible:
+    enum:
+      - samsung,exynos-bus
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: bus
+
+  devfreq:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Parent bus device. Valid and required only for the passive bus devices.
+
+  devfreq-events:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    minItems: 1
+    maxItems: 4
+    description:
+      Devfreq-event device to monitor the current utilization of buses. Valid
+      and required only for the parent bus devices.
+
+  exynos,saturation-ratio:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Percentage value which is used to calibrate the performance count against
+      total cycle count.  Valid only for the parent bus devices.
+
+  '#interconnect-cells':
+    const: 0
+
+  interconnects:
+    minItems: 1
+    maxItems: 2
+
+  operating-points-v2: true
+
+  samsung,data-clock-ratio:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    default: 8
+    description:
+      Ratio of the data throughput in B/s to minimum data clock frequency in
+      Hz.
+
+  vdd-supply:
+    description:
+      Main bus power rail. Valid and required only for the parent bus devices.
+
+required:
+  - compatible
+  - clocks
+  - clock-names
+  - operating-points-v2
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/exynos3250.h>
+
+    bus-dmc {
+        compatible = "samsung,exynos-bus";
+        clocks = <&cmu_dmc CLK_DIV_DMC>;
+        clock-names = "bus";
+        operating-points-v2 = <&bus_dmc_opp_table>;
+        devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
+        vdd-supply = <&buck1_reg>;
+    };
+
+    ppmu_dmc0: ppmu@106a0000 {
+        compatible = "samsung,exynos-ppmu";
+        reg = <0x106a0000 0x2000>;
+        events {
+            ppmu_dmc0_3: ppmu-event3-dmc0 {
+                event-name = "ppmu-event3-dmc0";
+            };
+        };
+    };
+
+    bus_leftbus: bus-leftbus {
+        compatible = "samsung,exynos-bus";
+        clocks = <&cmu CLK_DIV_GDL>;
+        clock-names = "bus";
+        operating-points-v2 = <&bus_leftbus_opp_table>;
+        devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
+        vdd-supply = <&buck3_reg>;
+    };
+
+    bus-rightbus {
+        compatible = "samsung,exynos-bus";
+        clocks = <&cmu CLK_DIV_GDR>;
+        clock-names = "bus";
+        operating-points-v2 = <&bus_leftbus_opp_table>;
+        devfreq = <&bus_leftbus>;
+    };
+
+  - |
+    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>;
+        devfreq-events = <&ppmu_dmc0_3>, <&ppmu_dmc1_3>;
+        vdd-supply = <&buck1_reg>;
+    };
+
+    leftbus: bus-leftbus {
+        compatible = "samsung,exynos-bus";
+        clocks = <&clock CLK_DIV_GDL>;
+        clock-names = "bus";
+        operating-points-v2 = <&bus_leftbus_opp_table>;
+        interconnects = <&dmc>;
+        #interconnect-cells = <0>;
+        devfreq-events = <&ppmu_leftbus_3>, <&ppmu_rightbus_3>;
+        vdd-supply = <&buck3_reg>;
+    };
+
+    display: bus-display {
+        compatible = "samsung,exynos-bus";
+        clocks = <&clock CLK_DIV_ACLK_266>;
+        clock-names = "bus";
+        operating-points-v2 = <&bus_display_opp_table>;
+        interconnects = <&leftbus &dmc>;
+        #interconnect-cells = <0>;
+        devfreq = <&leftbus>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 7c9187635801..19875f60ebb1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4328,7 +4328,7 @@  L:	linux-pm@vger.kernel.org
 L:	linux-samsung-soc@vger.kernel.org
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git
-F:	Documentation/devicetree/bindings/devfreq/exynos-bus.txt
+F:	Documentation/devicetree/bindings/interconnect/samsung,exynos-bus.yaml
 F:	drivers/devfreq/exynos-bus.c
 
 BUSLOGIC SCSI DRIVER